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Sample records for tsunami wave propagation

  1. Speeding up tsunami wave propagation modeling

    NASA Astrophysics Data System (ADS)

    Lavrentyev, Mikhail; Romanenko, Alexey

    2014-05-01

    Trans-oceanic wave propagation is one of the most time/CPU consuming parts of the tsunami modeling process. The so-called Method Of Splitting Tsunami (MOST) software package, developed at PMEL NOAA USA (Pacific Marine Environmental Laboratory of the National Oceanic and Atmospheric Administration, USA), is widely used to evaluate the tsunami parameters. However, it takes time to simulate trans-ocean wave propagation, that is up to 5 hours CPU time to "drive" the wave from Chili (epicenter) to the coast of Japan (even using a rather coarse computational mesh). Accurate wave height prediction requires fine meshes which leads to dramatic increase in time for simulation. Computation time is among the critical parameter as it takes only about 20 minutes for tsunami wave to approach the coast of Japan after earthquake at Japan trench or Sagami trench (as it was after the Great East Japan Earthquake on March 11, 2011). MOST solves numerically the hyperbolic system for three unknown functions, namely velocity vector and wave height (shallow water approximation). The system could be split into two independent systems by orthogonal directions (splitting method). Each system can be treated independently. This calculation scheme is well suited for SIMD architecture and GPUs as well. We performed adaptation of MOST package to GPU. Several numerical tests showed 40x performance gain for NVIDIA Tesla C2050 GPU vs. single core of Intel i7 processor. Results of numerical experiments were compared with other available simulation data. Calculation results, obtained at GPU, differ from the reference ones by 10^-3 cm of the wave height simulating 24 hours wave propagation. This allows us to speak about possibility to develop real-time system for evaluating tsunami danger.

  2. Analytical and Numerical Modeling of Tsunami Wave Propagation for double layer state in Bore

    NASA Astrophysics Data System (ADS)

    Yuvaraj, V.; Rajasekaran, S.; Nagarajan, D.

    2018-04-01

    Tsunami wave enters into the river bore in the landslide. Tsunami wave propagation are described in two-layer states. The velocity and amplitude of the tsunami wave propagation are calculated using the double layer. The numerical and analytical solutions are given for the nonlinear equation of motion of the wave propagation in a bore.

  3. Influence of source extension of 26 December 2004 Sumatra earthquake on character of tsunami wave propagation

    NASA Astrophysics Data System (ADS)

    Mazova, Raissa; Kisel'Man, Broneslav; Baranova, Natalya; Lobkovsky, Leopold

    2010-05-01

    The analysis of the Indian Ocean earthquake and tsunami on 26 December 2004 carried out in a number of works demonstrates that rupture process in the seismic source was realized during several minutes. In some works, there was suggested that a source probably consists of several segments with width near above hundred of kilometers and with total length more than 1000 km. Such a picture is consistent with subduction keyboard model of tsunamigenic earthquake (see, e.g. [1]) which treats the anomalously long source of Indian Ocean tsunami, caused by oblique subduction, as a multiblock piston mechanism with non-simultaneous realization of each block. Because of existing in literature uncertainty with source structure and movements at all its extent, it is interesting for given event to study in details the dependence of characteristics of surface water wave induced by seismic source on its extent [1,2]. In the work it was studied the influence of submarine seismic source extention to wave field distribution in basin of Bengal bay and central part of Indian ocean. To analyze, it was considered separately the influence of large segment of seismic source for given tsunami. On the basis of keyboard model it is considered the earthquake origin with extension near 1200 km comprises 3 seismic source: Sumatran, Andaman and Nicobar ones, each of which comprises 6, 4 and 3 keyboard blocks, respectively (1, 2 and 3 scenarios). It was calculated the maximal vertical displacement of these segments on 2-5 meters. The velocity of block movement was taken in correspondence with available data on characteristic times in the source. For scenario 1 tsunami source, formed at the ocean surface, generates almost circular wave which, due to bathymetry of given basin, preserve its form and propagates most quickly in west and south-west direction. To north-east, to Indian coast, the wave came with large delay, as compared with records of real mareographs. As follows from the wave field picture

  4. Tsunami Propagation Models Based on First Principles

    DTIC Science & Technology

    2012-11-21

    geodesic lines from the epicenter shown in the figure are great circles with a longitudinal separation of 90o, which define a ‘ lune ’ that covers one...past which the waves begin to converge according to Model C. A tsunami propagating in this lune does not encounter any continental landmass until...2011 Japan tsunami in a lune of angle 90o with wavefronts at intervals of 5,000 km The 2011 Japan tsunami was felt throughout the Pacific Ocean

  5. Traveltime delay relative to the maximum energy of the wave train for dispersive tsunamis propagating across the Pacific Ocean: the case of 2010 and 2015 Chilean Tsunamis

    NASA Astrophysics Data System (ADS)

    Poupardin, A.; Heinrich, P.; Hébert, H.; Schindelé, F.; Jamelot, A.; Reymond, D.; Sugioka, H.

    2018-05-01

    This paper evaluates the importance of frequency dispersion in the propagation of recent trans-Pacific tsunamis. Frequency dispersion induces a time delay for the most energetic waves, which increases for long propagation distances and short source dimensions. To calculate this time delay, propagation of tsunamis is simulated and analyzed from spectrograms of time-series at specific gauges in the Pacific Ocean. One- and two-dimensional simulations are performed by solving either shallow water or Boussinesq equations and by considering realistic seismic sources. One-dimensional sensitivity tests are first performed in a constant-depth channel to study the influence of the source width. Two-dimensional tests are then performed in a simulated Pacific Ocean with a 4000-m constant depth and by considering tectonic sources of 2010 and 2015 Chilean earthquakes. For these sources, both the azimuth and the distance play a major role in the frequency dispersion of tsunamis. Finally, simulations are performed considering the real bathymetry of the Pacific Ocean. Multiple reflections, refractions as well as shoaling of waves result in much more complex time series for which the effects of the frequency dispersion are hardly discernible. The main point of this study is to evaluate frequency dispersion in terms of traveltime delays by calculating spectrograms for a time window of 6 hours after the arrival of the first wave. Results of the spectral analysis show that the wave packets recorded by pressure and tide sensors in the Pacific Ocean seem to be better reproduced by the Boussinesq model than the shallow water model and approximately follow the theoretical dispersion relationship linking wave arrival times and frequencies. Additionally, a traveltime delay is determined above which effects of frequency dispersion are considered to be significant in terms of maximum surface elevations.

  6. Role of Compressibility on Tsunami Propagation

    NASA Astrophysics Data System (ADS)

    Abdolali, Ali; Kirby, James T.

    2017-12-01

    In the present paper, we aim to reduce the discrepancies between tsunami arrival times evaluated from tsunami models and real measurements considering the role of ocean compressibility. We perform qualitative studies to reveal the phase speed reduction rate via a modified version of the Mild Slope Equation for Weakly Compressible fluid (MSEWC) proposed by Sammarco et al. (2013). The model is validated against a 3-D computational model. Physical properties of surface gravity waves are studied and compared with those for waves evaluated from an incompressible flow solver over realistic geometry for 2011 Tohoku-oki event, revealing reduction in phase speed.Plain Language SummarySubmarine earthquakes and submarine mass failures (SMFs), can generate long gravitational <span class="hlt">waves</span> (or <span class="hlt">tsunamis</span>) that <span class="hlt">propagate</span> at the free surface. <span class="hlt">Tsunami</span> <span class="hlt">waves</span> can travel long distances and are known for their dramatic effects on coastal areas. Nowadays, numerical models are used to reconstruct the tsunamigenic events for many scientific and socioeconomic aspects i.e. <span class="hlt">Tsunami</span> Early Warning Systems, inundation mapping, risk and hazard analysis, etc. A number of typically neglected parameters in these models cause discrepancies between model outputs and observations. Most of the <span class="hlt">tsunami</span> models predict <span class="hlt">tsunami</span> arrival times at distant stations slightly early in comparison to observations. In this study, we show how ocean compressibility would affect the <span class="hlt">tsunami</span> <span class="hlt">wave</span> <span class="hlt">propagation</span> speed. In this framework, an efficient two-dimensional model equation for the weakly compressible ocean has been developed, validated and tested for simplified and real cases against three dimensional and incompressible solvers. Taking the effect of compressibility, the phase speed of surface gravity <span class="hlt">waves</span> is reduced compared to that of an incompressible fluid. Then, we used the model for the case of devastating Tohoku-Oki 2011 <span class="hlt">tsunami</span> event, improving the model accuracy. This</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUFMED53A0323L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUFMED53A0323L"><span>The <span class="hlt">Waves</span> and <span class="hlt">Tsunamis</span> Project</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lavin, M.; Strohschneider, D.; Maichle, R.; Frashure, K.; Micozzi, N.; Stephen, R. A.</p> <p>2005-12-01</p> <p>The goals of the <span class="hlt">Waves</span> and <span class="hlt">Tsunamis</span> Project are "to make <span class="hlt">waves</span> real" to middle school students and to teach them some fundamental concepts of <span class="hlt">waves</span>. The curriculum was designed in Fall 2004 (before the Sumatra <span class="hlt">Tsunami</span>) and involves an ocean scientist classroom visit, hands-on demonstrations, and an interactive website designed to explain ocean <span class="hlt">wave</span> properties. The website is called 'The Plymouth <span class="hlt">Wave</span> Lab' and it has had more than 40,000 hits since the Sumatra event. One inexpensive and interesting demonstration is based on a string composed of alternating elastic bands and paper clips. Washers can be added to the paper clips to construct strings with varying mass. For example, a tapered string with mass decreasing in the <span class="hlt">wave</span> <span class="hlt">propagation</span> direction is an analog of <span class="hlt">tsunami</span> <span class="hlt">waves</span> <span class="hlt">propagating</span> from deep to shallow water. The <span class="hlt">Waves</span> and <span class="hlt">Tsunamis</span> Project evolved as a collaborative effort involving an ocean science researcher and middle school science teachers. It was carried out through the direction of the Centers of Ocean Science Education Excellence New England (COSEE-NE) Ocean Science Education Institute (OSEI). COSEE-NE is involved in developing models for sustainable involvement of ocean science researchers in K-12 education ( http://necosee.net ). This work is supported by the National Science Foundation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSPO14B2758E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSPO14B2758E"><span>NOAA <span class="hlt">Propagation</span> Database Value in <span class="hlt">Tsunami</span> Forecast Guidance</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Eble, M. C.; Wright, L. M.</p> <p>2016-02-01</p> <p>The National Oceanic and Atmospheric Administration (NOAA) Center for <span class="hlt">Tsunami</span> Research (NCTR) has developed a <span class="hlt">tsunami</span> forecasting capability that combines a graphical user interface with data ingestion and numerical models to produce estimates of <span class="hlt">tsunami</span> <span class="hlt">wave</span> arrival times, amplitudes, current or water flow rates, and flooding at specific coastal communities. The capability integrates several key components: deep-ocean observations of <span class="hlt">tsunamis</span> in real-time, a basin-wide pre-computed <span class="hlt">propagation</span> database of water level and flow velocities based on potential pre-defined seismic unit sources, an inversion or fitting algorithm to refine the <span class="hlt">tsunami</span> source based on the observations during an event, and <span class="hlt">tsunami</span> forecast models. As <span class="hlt">tsunami</span> <span class="hlt">waves</span> <span class="hlt">propagate</span> across the ocean, observations from the deep ocean are automatically ingested into the application in real-time to better define the source of the <span class="hlt">tsunami</span> itself. Since passage of <span class="hlt">tsunami</span> <span class="hlt">waves</span> over a deep ocean reporting site is not immediate, we explore the value of the NOAA <span class="hlt">propagation</span> database in providing placeholder forecasts in advance of deep ocean observations. The <span class="hlt">propagation</span> database consists of water elevations and flow velocities pre-computed for 50 x 100 [km] unit sources in a continuous series along all known ocean subduction zones. The 2011 Japan Tohoku <span class="hlt">tsunami</span> is presented as the case study</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SPIE10466E..4VS','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SPIE10466E..4VS"><span>Cloud manifestations of atmospheric gravity <span class="hlt">waves</span> over the water area of the Kuril Islands during the <span class="hlt">propagation</span> of powerful transoceanic <span class="hlt">tsunamis</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Skorokhodov, A. V.; Shevchenko, G. V.; Astafurov, V. G.</p> <p>2017-11-01</p> <p>The investigation results of atmospheric gravity <span class="hlt">waves</span> cloudy manifestations observed over the water area of the Kuril Island ridge during the <span class="hlt">propagation</span> of powerful transoceanic <span class="hlt">tsunami</span> 2009-2010 are shown. The description of <span class="hlt">tsunami</span> characteristics is based on the use of information from autonomous deep-water stations of the Institute of Marine Geology and Geophysics FEB RAS in the Southern Kuril Islands and the <span class="hlt">Tsunami</span> Warning Service telemetering recorder located in one of the ports on Paramushir Island. The environment condition information was extracted from the results of remote sensing of the Earth from space by the MODIS sensor and aerological measurements at the meteorological station of Severo-Kurilsk. The results of analyzing the characteristics of <span class="hlt">wave</span> processes in the atmosphere and the ocean are discussed and their comparison is carried out.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=tsunami&pg=7&id=EJ758490','ERIC'); return false;" href="https://eric.ed.gov/?q=tsunami&pg=7&id=EJ758490"><span><span class="hlt">Waves</span> and <span class="hlt">Tsunami</span> Project</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Frashure, K. M.; Chen, R. F.; Stephen, R. A.; Bolmer, T.; Lavin, M.; Strohschneider, D.; Maichle, R.; Micozzi, N.; Cramer, C.</p> <p>2007-01-01</p> <p>Demonstrating <span class="hlt">wave</span> processes quantitatively in the classroom using standard classroom tools (such as Slinkys and <span class="hlt">wave</span> tanks) can be difficult. For example, <span class="hlt">waves</span> often travel too fast for students to actually measure amplitude or wavelength. Also, when teaching <span class="hlt">propagating</span> <span class="hlt">waves</span>, reflections from the ends set up standing <span class="hlt">waves</span>, which can confuse…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMNH51B1700O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMNH51B1700O"><span>A Study of the Effects of Seafloor Topography on <span class="hlt">Tsunami</span> <span class="hlt">Propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ohata, T.; Mikada, H.; Goto, T.; Takekawa, J.</p> <p>2011-12-01</p> <p>For <span class="hlt">tsunami</span> disaster mitigation, we consider the phenomena related to <span class="hlt">tsunami</span> in terms of the generation, <span class="hlt">propagation</span>, and run-up to the coast. With consideration for these three phenomena, we have to consider <span class="hlt">tsunami</span> <span class="hlt">propagation</span> to predict the arrival time and the run-up height of <span class="hlt">tsunami</span>. Numerical simulations of <span class="hlt">tsunami</span> that <span class="hlt">propagates</span> from the source location to the coast have been widely used to estimate these important parameters. When a <span class="hlt">tsunami</span> <span class="hlt">propagates</span>, however, reflected and scattered <span class="hlt">waves</span> arrive as later phases of <span class="hlt">tsunami</span>. These <span class="hlt">waves</span> are generated by the changes of water depth, and could influence the height estimation, especially in later phases. The maximum height of <span class="hlt">tsunami</span> could be observed not as the first arrivals but as the later phases, therefore it is necessary to consider the effects of the seafloor topography on <span class="hlt">tsunami</span> <span class="hlt">propagation</span>. Since many simulations, however, mainly focus on the prediction of the first arrival times and the initial height of <span class="hlt">tsunami</span>, it is difficult to simulate the later phases that are important for the <span class="hlt">tsunami</span> disaster mitigation in the conventional methods. In this study, we investigate the effects of the seafloor topography on <span class="hlt">tsunami</span> <span class="hlt">propagation</span> after accommodating a <span class="hlt">tsunami</span> simulation to the superposition of reflected and refracted <span class="hlt">waves</span> caused by the smooth changes of water depths. Developing the new numerical code, we consider how the effects of the sea floor topography affect on the <span class="hlt">tsunami</span> <span class="hlt">propagation</span>, comparing with the <span class="hlt">tsunami</span> simulated by the conventional method based on the liner long <span class="hlt">wave</span> theory. Our simulation employs the three dimensional in-equally spaced grids in finite difference method (FDM) to introduce the real seafloor topography. In the simulation, we import the seafloor topography from the real bathymetry data near the Sendai-Bay, off the northeast Tohoku region, Japan, and simulate the <span class="hlt">tsunami</span> <span class="hlt">propagation</span> over the varying seafloor topography there. Comparing with the <span class="hlt">tsunami</span> simulated by the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.S53A1036M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.S53A1036M"><span>New Theory for <span class="hlt">Tsunami</span> <span class="hlt">Propagation</span> and Estimation of <span class="hlt">Tsunami</span> Source Parameters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mindlin, I. M.</p> <p>2007-12-01</p> <p>In numerical studies based on the shallow water equations for <span class="hlt">tsunami</span> <span class="hlt">propagation</span>, vertical accelerations and velocities within the sea water are neglected, so a <span class="hlt">tsunami</span> is usually supposed to be produced by an initial free surface displacement in the initially still sea. In the present work, new theory for <span class="hlt">tsunami</span> <span class="hlt">propagation</span> across the deep sea is discussed, that accounts for the vertical accelerations and velocities. The theory is based on the solutions for the water surface displacement obtained in [Mindlin I.M. Integrodifferential equations in dynamics of a heavy layered liquid. Moscow: Nauka*Fizmatlit, 1996 (Russian)]. The solutions are valid when horizontal dimensions of the initially disturbed area in the sea surface are much larger than the vertical displacement of the surface, which applies to the earthquake <span class="hlt">tsunamis</span>. It is shown that any <span class="hlt">tsunami</span> is a combination of specific basic <span class="hlt">waves</span> found analytically (not superposition: the <span class="hlt">waves</span> are nonlinear), and consequently, the <span class="hlt">tsunami</span> source (i.e., the initially disturbed body of water) can be described by the numerable set of the parameters involved in the combination. Thus the problem of theoretical reconstruction of a <span class="hlt">tsunami</span> source is reduced to the problem of estimation of the parameters. The <span class="hlt">tsunami</span> source can be modelled approximately with the use of a finite number of the parameters. Two-parametric model is discussed thoroughly. A method is developed for estimation of the model's parameters using the arrival times of the <span class="hlt">tsunami</span> at certain locations, the maximum <span class="hlt">wave</span>-heights obtained from tide gauge records at the locations, and the distances between the earthquake's epicentre and each of the locations. In order to evaluate the practical use of the theory, four <span class="hlt">tsunamis</span> of different magnitude occurred in Japan are considered. For each of the <span class="hlt">tsunamis</span>, the <span class="hlt">tsunami</span> energy (E below), the duration of the <span class="hlt">tsunami</span> source formation T, the maximum water elevation in the <span class="hlt">wave</span> originating area H, mean radius of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1811809K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1811809K"><span><span class="hlt">Tsunami</span> focusing and leading <span class="hlt">wave</span> height</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kanoglu, Utku</p> <p>2016-04-01</p> <p>Field observations from <span class="hlt">tsunami</span> events show that sometimes the maximum <span class="hlt">tsunami</span> amplitude might not occur for the first <span class="hlt">wave</span>, such as the maximum <span class="hlt">wave</span> from the 2011 Japan <span class="hlt">tsunami</span> reaching to Papeete, Tahiti as a fourth <span class="hlt">wave</span> 72 min later after the first <span class="hlt">wave</span>. This might mislead local authorities and give a wrong sense of security to the public. Recently, Okal and Synolakis (2016, Geophys. J. Int. 204, 719-735) discussed "the factors contributing to the sequencing of <span class="hlt">tsunami</span> <span class="hlt">waves</span> in the far field." They consider two different generation mechanisms through an axial symmetric source -circular plug; one, Le Mehaute and Wang's (1995, World Scientific, 367 pp.) formalism where irritational <span class="hlt">wave</span> <span class="hlt">propagation</span> is formulated in the framework of investigating <span class="hlt">tsunamis</span> generated by underwater explosions and two, Hammack's formulation (1972, Ph.D. Dissertation, Calif. Inst. Tech., 261 pp., Pasadena) which introduces deformation at the ocean bottom and does not represent an immediate deformation of the ocean surface, i.e. time dependent ocean surface deformation. They identify the critical distance for transition from the first <span class="hlt">wave</span> being largest to the second <span class="hlt">wave</span> being largest. To verify sequencing for a finite length source, Okal and Synolakis (2016) is then used NOAA's validated and verified real time forecasting numerical model MOST (Titov and Synolakis, 1998, J. Waterw. Port Coast. Ocean Eng., 124, 157-171) through Synolakis et al. (2008, Pure Appl. Geophys. 165, 2197-2228). As a reference, they used the parameters of the 1 April 2014 Iquique, Chile earthquake over real bathymetry, variants of this source (small, big, wide, thin, and long) over a flat bathymetry, and 2010 Chile and 211 Japan <span class="hlt">tsunamis</span> over both real and flat bathymetries to explore the influence of the fault parameters on sequencing. They identified that sequencing more influenced by the source width rather than the length. We extend Okal and Synolakis (2016)'s analysis to an initial N-<span class="hlt">wave</span> form (Tadepalli</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH14A..04T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH14A..04T"><span><span class="hlt">Tsunami</span> <span class="hlt">Waves</span> Joint Inversion Using <span class="hlt">Tsunami</span> Inundation, <span class="hlt">Tsunami</span> Deposits Distribution and Marine-Terrestrial Sediment Signal in <span class="hlt">Tsunami</span> Deposit</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tang, H.; WANG, J.</p> <p>2017-12-01</p> <p>Population living close to coastlines is increasing, which creates higher risks due to coastal hazards, such as the <span class="hlt">tsunami</span>. However, the generation of a <span class="hlt">tsunami</span> is not fully understood yet, especially for paleo-<span class="hlt">tsunami</span>. <span class="hlt">Tsunami</span> deposits are one of the concrete evidence in the geological record which we can apply for studying paleo-<span class="hlt">tsunami</span>. The understanding of <span class="hlt">tsunami</span> deposits has significantly improved over the last decades. There are many inversion models (e.g. TsuSedMod, TSUFLIND, and TSUFLIND-EnKF) to study the overland-flow characteristics based on <span class="hlt">tsunami</span> deposits. However, none of them tries to reconstruct offshore <span class="hlt">tsunami</span> <span class="hlt">wave</span> characteristics (<span class="hlt">wave</span> form, <span class="hlt">wave</span> height, and length) based on <span class="hlt">tsunami</span> deposits. Here we present a state-of-the-art inverse approach to reconstruct offshore <span class="hlt">tsunami</span> <span class="hlt">wave</span> based on the <span class="hlt">tsunami</span> inundation data, the spatial distribution of <span class="hlt">tsunami</span> deposits and Marine-terrestrial sediment signal in the <span class="hlt">tsunami</span> deposits. Ensemble Kalman Filter (EnKF) Method is used for assimilating both sediment transport simulations and the field observation data. While more computationally expensive, the EnKF approach potentially provides more accurate reconstructions for <span class="hlt">tsunami</span> waveform. In addition to the improvement of inversion results, the ensemble-based method can also quantify the uncertainties of the results. Meanwhile, joint inversion improves the resolution of <span class="hlt">tsunami</span> <span class="hlt">waves</span> compared with inversions using any single data type. The method will be tested by field survey data and gauge data from the 2011 Tohoku <span class="hlt">tsunami</span> on Sendai plain area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA......292W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA......292W"><span>Generation, <span class="hlt">propagation</span> and run-up of <span class="hlt">tsunamis</span> due to the Chicxulub impact event</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weisz, R.; Wuennenmann, K.; Bahlburg, H.</p> <p>2003-04-01</p> <p>The Chicxulub impact event can be investigated in (1) local, (2) regional and in (3) global scales. Our investigations focus on the regional scale, especially on the influence of <span class="hlt">tsunami</span> <span class="hlt">waves</span> on the coast around the Gulf of Mexico caused by the impact. During an impact two types of <span class="hlt">tsunamis</span> are generated. The first <span class="hlt">wave</span> is known as the "rim <span class="hlt">wave</span>" and is generated in front of the ejecta curtain. The second one is linked to the late modification stage of the impact and results from the collapsing cavity of water. We designate this <span class="hlt">wave</span> as "collapse <span class="hlt">wave</span>". The "rim <span class="hlt">wave</span>" and "collapse <span class="hlt">wave</span>" are able to <span class="hlt">propagate</span> over long distances, without a significant loss of <span class="hlt">wave</span> amplitude. Corresponding to the amplitudes, the <span class="hlt">waves</span> have a potentially large influence on the coastal areas. Run-up distance and run-up height can be used as parameters for describing this influence. We are utilizing a multimaterial hydrocode (SALE) to simulate the generation of <span class="hlt">tsunami</span> <span class="hlt">waves</span>. The <span class="hlt">propagation</span> of the <span class="hlt">waves</span> is based on the non-linear shallow water theory, because <span class="hlt">tsunami</span> <span class="hlt">waves</span> are defined to be long <span class="hlt">waves</span>. The position of the coast line varies according to the <span class="hlt">tsunami</span> run-up and is implemented with open boundary conditions. We show with our investigations (1) the generation of <span class="hlt">tsunami</span> <span class="hlt">waves</span> due to shallow water impacts, (2) <span class="hlt">wave</span> damping during <span class="hlt">propagation</span>, and (3) the influence of the "rim <span class="hlt">wave</span>" and the "collapse <span class="hlt">wave</span>" on the coastal areas. Here, we present our first results from numerical modeling of <span class="hlt">tsunami</span> <span class="hlt">waves</span> owing to a Chicxulub sized impactor. The characteristics of the “rim wave” depend on the size of the bolide and the water depth. However, the amplitude and velocity of the “collapse wave” is only determined by the water depth in the impact area. The numerical modeling of the <span class="hlt">tsunami</span> <span class="hlt">propagation</span> and run-up is calculated along a section from the impact point towards to the west and gives the moderate damping of both <span class="hlt">waves</span> and the run-up on the coastal area. As a first</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1212469-first-tsunami-gravity-wave-detection-ionospheric-radio-occultation-data','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1212469-first-tsunami-gravity-wave-detection-ionospheric-radio-occultation-data"><span>First <span class="hlt">tsunami</span> gravity <span class="hlt">wave</span> detection in ionospheric radio occultation data</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Coïsson, Pierdavide; Lognonné, Philippe; Walwer, Damian; ...</p> <p>2015-05-09</p> <p>After the 11 March 2011 earthquake and <span class="hlt">tsunami</span> off the coast of Tohoku, the ionospheric signature of the displacements induced in the overlying atmosphere has been observed by ground stations in various regions of the Pacific Ocean. We analyze here the data of radio occultation satellites, detecting the <span class="hlt">tsunami</span>-driven gravity <span class="hlt">wave</span> for the first time using a fully space-based ionospheric observation system. One satellite of the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) recorded an occultation in the region above the <span class="hlt">tsunami</span> 2.5 h after the earthquake. The ionosphere was sounded from top to bottom, thus providing themore » vertical structure of the gravity <span class="hlt">wave</span> excited by the <span class="hlt">tsunami</span> <span class="hlt">propagation</span>, observed as oscillations of the ionospheric Total Electron Content (TEC). The observed vertical wavelength was about 50 km, with maximum amplitude exceeding 1 total electron content unit when the occultation reached 200 km height. We compared the observations with synthetic data obtained by summation of the <span class="hlt">tsunami</span>-coupled gravity normal modes of the Earth/Ocean/atmosphere system, which models the associated motion of the ionosphere plasma. These results provide experimental constraints on the attenuation of the gravity <span class="hlt">wave</span> with altitude due to atmosphere viscosity, improving the understanding of the <span class="hlt">propagation</span> of <span class="hlt">tsunami</span>-driven gravity <span class="hlt">waves</span> in the upper atmosphere. They demonstrate that the amplitude of the <span class="hlt">tsunami</span> can be estimated to within 20% by the recorded ionospheric data.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH21D..08S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH21D..08S"><span>Challenges in Defining <span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Height</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stroker, K. J.; Dunbar, P. K.; Mungov, G.; Sweeney, A.; Arcos, N. P.</p> <p>2017-12-01</p> <p>The NOAA National Centers for Environmental Information (NCEI) and co-located World Data Service for Geophysics maintain the global <span class="hlt">tsunami</span> archive consisting of the historical <span class="hlt">tsunami</span> database, imagery, and raw and processed water level data. The historical <span class="hlt">tsunami</span> database incorporates, where available, maximum <span class="hlt">wave</span> heights for each coastal tide gauge and deep-ocean buoy that recorded a <span class="hlt">tsunami</span> signal. These data are important because they are used for <span class="hlt">tsunami</span> hazard assessment, model calibration, validation, and forecast and warning. There have been ongoing discussions in the <span class="hlt">tsunami</span> community about the correct way to measure and report these <span class="hlt">wave</span> heights. It is important to understand how these measurements might vary depending on how the data were processed and the definition of maximum <span class="hlt">wave</span> height. On September 16, 2015, an 8.3 Mw earthquake located 48 km west of Illapel, Chile generated a <span class="hlt">tsunami</span> that was observed all over the Pacific region. We processed the time-series water level data for 57 tide gauges that recorded this <span class="hlt">tsunami</span> and compared the maximum <span class="hlt">wave</span> heights determined from different definitions. We also compared the maximum <span class="hlt">wave</span> heights from the NCEI-processed data with the heights reported by the NOAA <span class="hlt">Tsunami</span> Warning Centers. We found that in the near field different methods of determining the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights could result in large differences due to possible instrumental clipping. We also found that the maximum peak is usually larger than the maximum amplitude (½ peak-to-trough), but the differences for the majority of the stations were <20 cm. For this event, the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights determined by either definition (maximum peak or amplitude) would have validated the forecasts issued by the NOAA <span class="hlt">Tsunami</span> Warning Centers. Since there is currently only one field in the NCEI historical <span class="hlt">tsunami</span> database to store the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> height, NCEI will consider adding an additional field for the maximum peak measurement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ISPAr42W7.1291M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ISPAr42W7.1291M"><span>Spatiotemporal Visualization of <span class="hlt">Tsunami</span> <span class="hlt">Waves</span> Using Kml on Google Earth</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mohammadi, H.; Delavar, M. R.; Sharifi, M. A.; Pirooz, M. D.</p> <p>2017-09-01</p> <p>Disaster risk is a function of hazard and vulnerability. Risk is defined as the expected losses, including lives, personal injuries, property damages, and economic disruptions, due to a particular hazard for a given area and time period. Risk assessment is one of the key elements of a natural disaster management strategy as it allows for better disaster mitigation and preparation. It provides input for informed decision making, and increases risk awareness among decision makers and other stakeholders. Virtual globes such as Google Earth can be used as a visualization tool. Proper spatiotemporal graphical representations of the concerned risk significantly reduces the amount of effort to visualize the impact of the risk and improves the efficiency of the decision-making process to mitigate the impact of the risk. The spatiotemporal visualization of <span class="hlt">tsunami</span> <span class="hlt">waves</span> for disaster management process is an attractive topic in geosciences to assist investigation of areas at <span class="hlt">tsunami</span> risk. In this paper, a method for coupling virtual globes with <span class="hlt">tsunami</span> <span class="hlt">wave</span> arrival time models is presented. In this process we have shown 2D+Time of <span class="hlt">tsunami</span> <span class="hlt">waves</span> for <span class="hlt">propagation</span> and inundation of <span class="hlt">tsunami</span> <span class="hlt">waves</span>, both coastal line deformation, and the flooded areas. In addition, the worst case scenario of <span class="hlt">tsunami</span> on Chabahar port derived from <span class="hlt">tsunami</span> modelling is also presented using KML on google earth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRA..123.4329R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRA..123.4329R"><span><span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Height Estimation from GPS-Derived Ionospheric Data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rakoto, Virgile; Lognonné, Philippe; Rolland, Lucie; Coïsson, P.</p> <p>2018-05-01</p> <p>Large underwater earthquakes (Mw>7) can transmit part of their energy to the surrounding ocean through large seafloor motions, generating <span class="hlt">tsunamis</span> that <span class="hlt">propagate</span> over long distances. The forcing effect of <span class="hlt">tsunami</span> <span class="hlt">waves</span> on the atmosphere generates internal gravity <span class="hlt">waves</span> that, when they reach the upper atmosphere, produce ionospheric perturbations. These perturbations are frequently observed in the total electron content (TEC) measured by multifrequency Global Navigation Satellite Systems (GNSS) such as GPS, GLONASS, and, in the future, Galileo. This paper describes the first inversion of the variation in sea level derived from GPS TEC data. We used a least squares inversion through a normal-mode summation modeling. This technique was applied to three <span class="hlt">tsunamis</span> in far field associated to the 2012 Haida Gwaii, 2006 Kuril Islands, and 2011 Tohoku events and for Tohoku also in close field. With the exception of the Tohoku far-field case, for which the <span class="hlt">tsunami</span> reconstruction by the TEC inversion is less efficient due to the ionospheric noise background associated to geomagnetic storm, which occurred on the earthquake day, we show that the peak-to-peak amplitude of the sea level variation inverted by this method can be compared to the <span class="hlt">tsunami</span> <span class="hlt">wave</span> height measured by a DART buoy with an error of less than 20%. This demonstrates that the inversion of TEC data with a <span class="hlt">tsunami</span> normal-mode summation approach is able to estimate quite accurately the amplitude and waveform of the first <span class="hlt">tsunami</span> arrival.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007NHESS...7..741D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007NHESS...7..741D"><span><span class="hlt">Tsunami</span> <span class="hlt">propagation</span> modelling - a sensitivity study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dao, M. H.; Tkalich, P.</p> <p>2007-12-01</p> <p>Indian Ocean (2004) <span class="hlt">Tsunami</span> and following tragic consequences demonstrated lack of relevant experience and preparedness among involved coastal nations. After the event, scientific and forecasting circles of affected countries have started a capacity building to tackle similar problems in the future. Different approaches have been used for <span class="hlt">tsunami</span> <span class="hlt">propagation</span>, such as Boussinesq and Nonlinear Shallow Water Equations (NSWE). These approximations were obtained assuming different relevant importance of nonlinear, dispersion and spatial gradient variation phenomena and terms. The paper describes further development of original TUNAMI-N2 model to take into account additional phenomena: astronomic tide, sea bottom friction, dispersion, Coriolis force, and spherical curvature. The code is modified to be suitable for operational forecasting, and the resulting version (TUNAMI-N2-NUS) is verified using test cases, results of other models, and real case scenarios. Using the 2004 <span class="hlt">Tsunami</span> event as one of the scenarios, the paper examines sensitivity of numerical solutions to variation of different phenomena and parameters, and the results are analyzed and ranked accordingly.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li class="active"><span>1</span></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_1 --> <div id="page_2" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li class="active"><span>2</span></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="21"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008spa..book.1535W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008spa..book.1535W"><span>Seismic <span class="hlt">Wave</span> <span class="hlt">Propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Xianyun; Wu, Ru-Shan</p> <p></p> <p>A seismic <span class="hlt">wave</span> is a mechanical disturbance or energy packet that can <span class="hlt">propagate</span> from point to point in the Earth. Seismic <span class="hlt">waves</span> can be generated by a sudden release of energy such as an earthquake, volcanic eruption, or chemical explosion. There are several types of seismic <span class="hlt">waves</span>, often classified as body <span class="hlt">waves</span>, which <span class="hlt">propagate</span> through the volume of the Earth, and surface <span class="hlt">waves</span>, which travel along the surface of the Earth. Compressional and shear <span class="hlt">waves</span> are the two main types of body <span class="hlt">wave</span> and Rayleigh and Love <span class="hlt">waves</span> are the most common forms of surface <span class="hlt">wave</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PApGe.174.3043D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PApGe.174.3043D"><span>Challenges in Defining <span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Heights</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dunbar, Paula; Mungov, George; Sweeney, Aaron; Stroker, Kelly; Arcos, Nicolas</p> <p>2017-08-01</p> <p>The National Oceanic and Atmospheric Administration (NOAA) National Centers for Environmental Information (NCEI) and co-located World Data Service for Geophysics maintain the global <span class="hlt">tsunami</span> archive consisting of the historical <span class="hlt">tsunami</span> database, imagery, and raw and processed water level data. The historical <span class="hlt">tsunami</span> database incorporates, where available, maximum <span class="hlt">wave</span> heights for each coastal tide gauge and deep-ocean buoy that recorded a <span class="hlt">tsunami</span> signal. These data are important because they are used for <span class="hlt">tsunami</span> hazard assessment, model calibration, validation, and forecast and warning. There have been ongoing discussions in the <span class="hlt">tsunami</span> community about the correct way to measure and report these <span class="hlt">wave</span> heights. It is important to understand how these measurements might vary depending on how the data were processed and the definition of maximum <span class="hlt">wave</span> height. On September 16, 2015, an 8.3 M w earthquake located 48 km west of Illapel, Chile generated a <span class="hlt">tsunami</span> that was observed all over the Pacific region. We processed the time-series water level data for 57 coastal tide gauges that recorded this <span class="hlt">tsunami</span> and compared the maximum <span class="hlt">wave</span> heights determined from different definitions. We also compared the maximum <span class="hlt">wave</span> heights from the NCEI-processed data with the heights reported by the NOAA <span class="hlt">Tsunami</span> Warning Centers. We found that in the near field different methods of determining the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights could result in large differences due to possible instrumental clipping. We also found that the maximum peak is usually larger than the maximum amplitude (½ peak-to-trough), but the differences for the majority of the stations were <20 cm. For this event, the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights determined by either definition (maximum peak or amplitude) would have validated the forecasts issued by the NOAA <span class="hlt">Tsunami</span> Warning Centers. Since there is currently only one field in the NCEI historical <span class="hlt">tsunami</span> database to store the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> height for each tide gauge and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015E%26ES...23a2007Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015E%26ES...23a2007Z"><span>A shallow water model for the <span class="hlt">propagation</span> of <span class="hlt">tsunami</span> via Lattice Boltzmann method</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zergani, Sara; Aziz, Z. A.; Viswanathan, K. K.</p> <p>2015-01-01</p> <p>An efficient implementation of the lattice Boltzmann method (LBM) for the numerical simulation of the <span class="hlt">propagation</span> of long ocean <span class="hlt">waves</span> (e.g. <span class="hlt">tsunami</span>), based on the nonlinear shallow water (NSW) <span class="hlt">wave</span> equation is presented. The LBM is an alternative numerical procedure for the description of incompressible hydrodynamics and has the potential to serve as an efficient solver for incompressible flows in complex geometries. This work proposes the NSW equations for the irrotational surface <span class="hlt">waves</span> in the case of complex bottom elevation. In recent time, equation involving shallow water is the current norm in modelling <span class="hlt">tsunami</span> operations which include the <span class="hlt">propagation</span> zone estimation. Several test-cases are presented to verify our model. Some implications to <span class="hlt">tsunami</span> <span class="hlt">wave</span> modelling are also discussed. Numerical results are found to be in excellent agreement with theory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH14A..08T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH14A..08T"><span>Modeling Extra-Long <span class="hlt">Tsunami</span> <span class="hlt">Propagation</span>: Assessing Data, Model Accuracy and Forecast Implications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Titov, V. V.; Moore, C. W.; Rabinovich, A.</p> <p>2017-12-01</p> <p>Detecting and modeling <span class="hlt">tsunamis</span> <span class="hlt">propagating</span> tens of thousands of kilometers from the source is a formidable scientific challenge and seemingly satisfies only scientific curiosity. However, results of such analyses produce a valuable insight into the <span class="hlt">tsunami</span> <span class="hlt">propagation</span> dynamics, model accuracy and would provide important implications for <span class="hlt">tsunami</span> forecast. The Mw = 9.3 megathrust earthquake of December 26, 2004 off the coast of Sumatra generated a <span class="hlt">tsunami</span> that devastated Indian Ocean coastlines and spread into the Pacific and Atlantic oceans. The <span class="hlt">tsunami</span> was recorded by a great number of coastal tide gauges, including those located in 15-25 thousand kilometers from the source area. To date, it is still the farthest instrumentally detected <span class="hlt">tsunami</span>. The data from these instruments throughout the world oceans enabled to estimate various statistical parameters and energy decay of this event. High-resolution records of this <span class="hlt">tsunami</span> from DARTs 32401 (offshore of northern Chile), 46405 and NeMO (both offshore of the US West Coast), combined with the mainland tide gauge measurements enabled us to examine far-field characteristics of the 2004 in the Pacific Ocean and to compare the results of global numerical simulations with the observations. Despite their small heights (less than 2 cm at deep-ocean locations), the records demonstrated consistent spatial and temporal structure. The numerical model described well the frequency content, amplitudes and general structure of the observed <span class="hlt">waves</span> at deep-ocean and coastal gages. We present analysis of the measurements and comparison with model data to discuss implication for <span class="hlt">tsunami</span> forecast accuracy. Model study for such extreme distances from the <span class="hlt">tsunami</span> source and at extra-long times after the event is an attempt to find accuracy bounds for <span class="hlt">tsunami</span> models and accuracy limitations of model use for forecast. We discuss results in application to <span class="hlt">tsunami</span> model forecast and <span class="hlt">tsunami</span> modeling in general.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11..502P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11..502P"><span>The 1755 <span class="hlt">tsunami</span> <span class="hlt">propagation</span> in Atlantics and its effects on the French West Indies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pelinovsky, E.; Zahibo, N.; Yalciner, A.; Zaitsev, A.; Talipova, T.; Chernov, A.; Insel, I.; Dilmen, D.; Ozer, C.; Nikolkina, I.</p> <p>2009-04-01</p> <p>The present study examines the <span class="hlt">propagation</span> of <span class="hlt">tsunami</span> <span class="hlt">waves</span> generated by the 1755 Lisbon earthquake in the Atlantic Ocean and its effects on the coasts of the French West Indies in the Caribbean Sea. Historical data of <span class="hlt">tsunami</span> manifestation in the French West Indies are briefly reproduced. The mathematical model named NAMI DANCE which solves the shallow-water equations has been applied in the computations. Three possible seismic source alternatives of the <span class="hlt">tsunami</span> source are selected for 1755 event in the simulations. The results obtained from the simulations demonstrate that the directivity of <span class="hlt">tsunami</span> energy is divided into two strong beams directed to the southern part of North America (Florida, the Bahamas) and to the northern part of South America (Brazil). The <span class="hlt">tsunami</span> <span class="hlt">waves</span> reach the Lesser Antilles in 7 hrs. The computed distribution of <span class="hlt">tsunami</span> <span class="hlt">wave</span> height along the coasts of Guadeloupe and Martinique are presented. Calculated maximum of <span class="hlt">wave</span> amplitudes reached 2 m in Guadeloupe and 1.5 m in Martinique. These results are also in agreement with observed data (1.8 - 3 m). The experience and data obtained in this study show that transatlantic events must also be considered in the <span class="hlt">tsunami</span> hazard assessment and development of mitigation strategies for the French West Indies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/tsunamis.html','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/tsunamis.html"><span><span class="hlt">Tsunamis</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>A <span class="hlt">tsunami</span> is a series of huge ocean <span class="hlt">waves</span> created by an underwater disturbance. Causes include earthquakes, landslides, volcanic ... space that strike the surface of Earth. A <span class="hlt">tsunami</span> can move hundreds of miles per hour in ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRC..122.5786B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRC..122.5786B"><span><span class="hlt">Tsunami</span> and infragravity <span class="hlt">waves</span> impacting Antarctic ice shelves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bromirski, P. D.; Chen, Z.; Stephen, R. A.; Gerstoft, P.; Arcas, D.; Diez, A.; Aster, R. C.; Wiens, D. A.; Nyblade, A.</p> <p>2017-07-01</p> <p>The responses of the Ross Ice Shelf (RIS) to the 16 September 2015 8.3 (Mw) Chilean earthquake <span class="hlt">tsunami</span> (>75 s period) and to oceanic infragravity (IG) <span class="hlt">waves</span> (50-300 s period) were recorded by a broadband seismic array deployed on the RIS from November 2014 to November 2016. Here we show that <span class="hlt">tsunami</span> and IG-generated signals within the RIS <span class="hlt">propagate</span> at gravity <span class="hlt">wave</span> speeds (˜70 m/s) as water-ice coupled flexural-gravity <span class="hlt">waves</span>. IG band signals show measureable attenuation away from the shelf front. The response of the RIS to Chilean <span class="hlt">tsunami</span> arrivals is compared with modeled <span class="hlt">tsunami</span> forcing to assess ice shelf flexural-gravity <span class="hlt">wave</span> excitation by very long period (VLP; >300 s) gravity <span class="hlt">waves</span>. Displacements across the RIS are affected by gravity <span class="hlt">wave</span> incident direction, bathymetry under and north of the shelf, and water layer and ice shelf thicknesses. Horizontal displacements are typically about 10 times larger than vertical displacements, producing dynamical extensional motions that may facilitate expansion of existing fractures. VLP excitation is continuously observed throughout the year, with horizontal displacements highest during the austral winter with amplitudes exceeding 20 cm. Because VLP flexural-gravity <span class="hlt">waves</span> exhibit no discernable attenuation, this energy must <span class="hlt">propagate</span> to the grounding zone. Both IG and VLP band flexural-gravity <span class="hlt">waves</span> excite mechanical perturbations of the RIS that likely promote tabular iceberg calving, consequently affecting ice shelf evolution. Understanding these ocean-excited mechanical interactions is important to determine their effect on ice shelf stability to reduce uncertainty in the magnitude and rate of global sea level rise.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH23A1867K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH23A1867K"><span>Leading <span class="hlt">Wave</span> Amplitude of a <span class="hlt">Tsunami</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kanoglu, U.</p> <p>2015-12-01</p> <p>Okal and Synolakis (EGU General Assembly 2015, Geophysical Research Abstracts-Vol. 17-7622) recently discussed that why the maximum amplitude of a <span class="hlt">tsunami</span> might not occur for the first <span class="hlt">wave</span>. Okal and Synolakis list observations from 2011 Japan <span class="hlt">tsunami</span>, which reached to Papeete, Tahiti with a fourth <span class="hlt">wave</span> being largest and 72 min later after the first <span class="hlt">wave</span>; 1960 Chilean <span class="hlt">tsunami</span> reached Hilo, Hawaii with a maximum <span class="hlt">wave</span> arriving 1 hour later with a height of 5m, first <span class="hlt">wave</span> being only 1.2m. Largest later <span class="hlt">waves</span> is a problem not only for local authorities both in terms of warning to the public and rescue efforts but also mislead the public thinking that it is safe to return shoreline or evacuated site after arrival of the first <span class="hlt">wave</span>. Okal and Synolakis considered Hammack's (1972, Ph.D. Dissertation, Calif. Inst. Tech., 261 pp., Pasadena) linear dispersive analytical solution with a <span class="hlt">tsunami</span> generation through an uplifting of a circular plug on the ocean floor. They performed parametric study for the radius of the plug and the depth of the ocean since these are the independent scaling lengths in the problem. They identified transition distance, as the second <span class="hlt">wave</span> being larger, regarding the parameters of the problem. Here, we extend their analysis to an initial <span class="hlt">wave</span> field with a finite crest length and, in addition, to a most common <span class="hlt">tsunami</span> initial <span class="hlt">wave</span> form of N-<span class="hlt">wave</span> as presented by Tadepalli and Synolakis (1994, Proc. R. Soc. A: Math. Phys. Eng. Sci., 445, 99-112). We compare our results with non-dispersive linear shallow water <span class="hlt">wave</span> results as presented by Kanoglu et al. (2013, Proc. R. Soc. A: Math. Phys. Eng. Sci., 469, 20130015), investigating focusing feature. We discuss the results both in terms of leading <span class="hlt">wave</span> amplitude and <span class="hlt">tsunami</span> focusing. Acknowledgment: The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement no 603839 (Project ASTARTE - Assessment, Strategy and Risk</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70017833','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70017833"><span>Source parameters controlling the generation and <span class="hlt">propagation</span> of potential local <span class="hlt">tsunamis</span> along the cascadia margin</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, E.; Yoshioka, S.</p> <p>1996-01-01</p> <p>The largest uncertainty in assessing hazards from local <span class="hlt">tsunamis</span> along the Cascadia margin is estimating the possible earthquake source parameters. We investigate which source parameters exert the largest influence on <span class="hlt">tsunami</span> generation and determine how each parameter affects the amplitude of the local <span class="hlt">tsunami</span>. The following source parameters were analyzed: (1) type of faulting characteristic of the Cascadia subduction zone, (2) amount of slip during rupture, (3) slip orientation, (4) duration of rupture, (5) physical properties of the accretionary wedge, and (6) influence of secondary faulting. The effect of each of these source parameters on the quasi-static displacement of the ocean floor is determined by using elastic three-dimensional, finite-element models. The <span class="hlt">propagation</span> of the resulting <span class="hlt">tsunami</span> is modeled both near the coastline using the two-dimensional (x-t) Peregrine equations that includes the effects of dispersion and near the source using the three-dimensional (x-y-t) linear long-<span class="hlt">wave</span> equations. The source parameters that have the largest influence on local <span class="hlt">tsunami</span> excitation are the shallowness of rupture and the amount of slip. In addition, the orientation of slip has a large effect on the directivity of the <span class="hlt">tsunami</span>, especially for shallow dipping faults, which consequently has a direct influence on the length of coastline inundated by the <span class="hlt">tsunami</span>. Duration of rupture, physical properties of the accretionary wedge, and secondary faulting all affect the excitation of <span class="hlt">tsunamis</span> but to a lesser extent than the shallowness of rupture and the amount and orientation of slip. Assessment of the severity of the local <span class="hlt">tsunami</span> hazard should take into account that relatively large <span class="hlt">tsunamis</span> can be generated from anomalous '<span class="hlt">tsunami</span> earthquakes' that rupture within the accretionary wedge in comparison to interplate thrust earthquakes of similar magnitude. ?? 1996 Kluwer Academic Publishers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1983ReAer...1...13G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1983ReAer...1...13G"><span>VHF electromagnetic <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gole, P.</p> <p></p> <p>Theoretical and experimental study of large-scale VHF <span class="hlt">propagation</span> characteristics is presented. Certain phenomena that are difficult to model, such as the effects of ground near the antenna, are examined from a purely experimental point of view. The characteristics of electromagnetic <span class="hlt">waves</span> over a spherical surface and through a medium having a certain refractive index, such as is the case for <span class="hlt">waves</span> <span class="hlt">propagated</span> over the earth's surface, are analytically described. Two mathematical models are used, one for the case of the receiver being within the radioelectric horizon of the transmitter and the other for when it is not. <span class="hlt">Propagation</span> phenomena likely to increase the false alarm probability of an air surveillance radar are briefly considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRC..120.6865L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRC..120.6865L"><span>Impacts of tides on <span class="hlt">tsunami</span> <span class="hlt">propagation</span> due to potential Nankai Trough earthquakes in the Seto Inland Sea, Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Han Soo; Shimoyama, Tomohisa; Popinet, Stéphane</p> <p>2015-10-01</p> <p>The impacts of tides on extreme <span class="hlt">tsunami</span> <span class="hlt">propagation</span> due to potential Nankai Trough earthquakes in the Seto Inland Sea (SIS), Japan, are investigated through numerical experiments. <span class="hlt">Tsunami</span> experiments are conducted based on five scenarios that consider tides at four different phases, such as flood, high, ebb, and low tides. The probes that were selected arbitrarily in the Bungo and Kii Channels show less significant effects of tides on <span class="hlt">tsunami</span> heights and the arrival times of the first <span class="hlt">waves</span> than those that experience large tidal ranges in inner basins and bays of the SIS. For instance, the maximum <span class="hlt">tsunami</span> height and the arrival time at Toyomaesi differ by more than 0.5 m and nearly 1 h, respectively, depending on the tidal phase. The uncertainties defined in terms of calculated maximum <span class="hlt">tsunami</span> heights due to tides illustrate that the calculated maximum <span class="hlt">tsunami</span> heights in the inner SIS with standing tides have much larger uncertainties than those of two channels with <span class="hlt">propagating</span> tides. Particularly in Harima Nada, the uncertainties due to the impacts of tides are greater than 50% of the <span class="hlt">tsunami</span> heights without tidal interaction. The results recommend simulate <span class="hlt">tsunamis</span> together with tides in shallow water environments to reduce the uncertainties involved with <span class="hlt">tsunami</span> modeling and predictions for <span class="hlt">tsunami</span> hazards preparedness. This article was corrected on 26 OCT 2015. See the end of the full text for details.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AdWR..115..273B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AdWR..115..273B"><span>A well-balanced meshless <span class="hlt">tsunami</span> <span class="hlt">propagation</span> and inundation model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brecht, Rüdiger; Bihlo, Alexander; MacLachlan, Scott; Behrens, Jörn</p> <p>2018-05-01</p> <p>We present a novel meshless <span class="hlt">tsunami</span> <span class="hlt">propagation</span> and inundation model. We discretize the nonlinear shallow-water equations using a well-balanced scheme relying on radial basis function based finite differences. For the inundation model, radial basis functions are used to extrapolate the dry region from nearby wet points. Numerical results against standard one- and two-dimensional benchmarks are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=3650&hterms=worlds+oceans&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dworlds%2Boceans','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=3650&hterms=worlds+oceans&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dworlds%2Boceans"><span>Deep Ocean <span class="hlt">Tsunami</span> <span class="hlt">Waves</span> off the Sri Lankan Coast</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2004-01-01</p> <p> fully understand the dynamics. Examination of other MISR images of this area, taken under similar illumination conditions, has not uncovered any surface patterns resembling those seen here. This image is an example of how MISR's multi-angular capability provides unique information for understanding how <span class="hlt">tsunamis</span> <span class="hlt">propagate</span>. Another application of MISR data enabled scientists to measure the motion of breaking <span class="hlt">tsunami</span> <span class="hlt">waves</span> along the eastern shores of Andhra Pradesh, India. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82 degrees North and 82 degrees South latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 26720 and utilize data from within blocks 85 to 86 within World Reference System-2 path 142. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. Image courtesy NASA/GSFC/LaRC/JPL, MISR Team. Text by Clare Averill (Raytheon ITSS/JPL); Michael Garay and David J. Diner (JPL, California Institute of Technology); and Vasily Titov (NOAA/Pacific Marine Environmental Laboratory and University of Washington/Joint Institute for the Study of the Atmosphere and Oceans).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-vger.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-vger.html"><span>Voyager 1: Three "<span class="hlt">Tsunami</span> <span class="hlt">Waves</span>" in Interstellar Space</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2017-03-22</p> <p>Voyager 1: Three "<span class="hlt">Tsunami</span> <span class="hlt">Waves</span>" in Interstellar Space. The Voyager 1 spacecraft has experienced three "<span class="hlt">tsunami</span> <span class="hlt">waves</span>" in interstellar space. Listen to how these <span class="hlt">waves</span> cause surrounding ionized matter to ring. More details on this sound can be found here: www.nasa.gov/jpl/nasa-voyager-t…nterstellar-space/</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.3805R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.3805R"><span>DTWT (Dispersive <span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Tool): a new tool for computing the complete dispersion of <span class="hlt">tsunami</span> travel time.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reymond, Dominique</p> <p>2017-04-01</p> <p>We present a tool for computing the complete arrival times of the dispersed <span class="hlt">wave</span>-train of a <span class="hlt">tsunami</span>. The calculus is made using the exact formulation of the <span class="hlt">tsunami</span> dispersion (and without approximations), at any desired periods between one hour or more (concerning the gravity <span class="hlt">waves</span> <span class="hlt">propagation</span>) until 10s (the highly dispersed mode). The computation of the travel times is based on the a summation of the necessary time for a <span class="hlt">tsunami</span> to cross all the elementary blocs of a grid of bathymetry following a path between the source and receiver at a given period. In addition the source dimensions and the focal mechanism are taken into account to adjust the minimum travel time to the different possible points of emission of the source. A possible application of this tool is to forecast the arrival time of late arrivals of <span class="hlt">tsunami</span> <span class="hlt">waves</span> that could produce the resonnance of some bays and sites at higher frequencies than the gravity mode. The theoretical arrival times are compared to the observed ones and to the results obtained by TTT (P. Wessel, 2009) and the ones obtained by numerical simulations. References: Wessel, P. (2009). Analysis of oberved and predicted <span class="hlt">tsunami</span> travel times for the Pacic and Indian oceans. Pure Appl. Geophys., 166:301-324.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1615964M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1615964M"><span><span class="hlt">Tsunami</span> Generation and <span class="hlt">Propagation</span> by 3D deformable Landslides and Application to Scenarios</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McFall, Brian C.; Fritz, Hermann M.</p> <p>2014-05-01</p> <p><span class="hlt">Tsunamis</span> generated by landslides and volcano flank collapse account for some of the most catastrophic natural disasters recorded and can be particularly devastative in the near field region due to locally high <span class="hlt">wave</span> amplitudes and runup. The events of 1958 Lituya Bay, 1963 Vajont reservoir, 1980 Spirit Lake, 2002 Stromboli and 2010 Haiti demonstrate the danger of <span class="hlt">tsunamis</span> generated by landslides or volcano flank collapses. Unfortunately critical field data from these events is lacking. Source and runup scenarios based on real world events are physically modeled using generalized Froude similarity in the three dimensional NEES <span class="hlt">tsunami</span> <span class="hlt">wave</span> basin at Oregon State University. A novel pneumatic landslide <span class="hlt">tsunami</span> generator (LTG) was deployed to simulate landslides with varying geometry and kinematics. The bathymetric and topographic scenarios tested with the LTG are the basin-wide <span class="hlt">propagation</span> and runup, fjord, curved headland fjord and a conical island setting representing a landslide off an island or a volcano flank collapse. The LTG consists of a sliding box filled with 1,350 kg of landslide material which is accelerated by means of four pneumatic pistons down a 2H:1V slope. The landslide is launched from the sliding box and continues to accelerate by gravitational forces up to velocities of 5 m/s. The landslide Froude number at impact with the water is in the range 1 <F <4. Two different materials are used to simulate landslides to study the granulometry effects: naturally rounded river gravel and cobble mixtures. Water surface elevations are recorded by an array of resistance <span class="hlt">wave</span> gauges. The landslide deformation is measured from above and underwater camera recordings. The landslide deposit is measured on the basin floor with a multiple transducer acoustic array (MTA). Landslide surface reconstruction and kinematics are determined with a stereo particle image velocimetry (PIV) system. <span class="hlt">Wave</span> runup is recorded with resistance <span class="hlt">wave</span> gauges along the slope and verified</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26119833','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26119833"><span>Widespread <span class="hlt">tsunami</span>-like <span class="hlt">waves</span> of 23-27 June in the Mediterranean and Black Seas generated by high-altitude atmospheric forcing.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Šepić, Jadranka; Vilibić, Ivica; Rabinovich, Alexander B; Monserrat, Sebastian</p> <p>2015-06-29</p> <p>A series of <span class="hlt">tsunami</span>-like <span class="hlt">waves</span> of non-seismic origin struck several southern European countries during the period of 23 to 27 June 2014. The event caused considerable damage from Spain to Ukraine. Here, we show that these <span class="hlt">waves</span> were long-period ocean oscillations known as meteorological <span class="hlt">tsunamis</span> which are generated by intense small-scale air pressure disturbances. An unique atmospheric synoptic pattern was tracked <span class="hlt">propagating</span> eastward over the Mediterranean and the Black seas in synchrony with onset times of observed <span class="hlt">tsunami</span> <span class="hlt">waves</span>. This pattern favoured generation and <span class="hlt">propagation</span> of atmospheric gravity <span class="hlt">waves</span> that induced pronounced <span class="hlt">tsunami</span>-like <span class="hlt">waves</span> through the Proudman resonance mechanism. This is the first documented case of a chain of destructive meteorological <span class="hlt">tsunamis</span> occurring over a distance of thousands of kilometres. Our findings further demonstrate that these events represent potentially dangerous regional phenomena and should be included in <span class="hlt">tsunami</span> warning systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4483776','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4483776"><span>Widespread <span class="hlt">tsunami</span>-like <span class="hlt">waves</span> of 23-27 June in the Mediterranean and Black Seas generated by high-altitude atmospheric forcing</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Šepić, Jadranka; Vilibić, Ivica; Rabinovich, Alexander B.; Monserrat, Sebastian</p> <p>2015-01-01</p> <p>A series of <span class="hlt">tsunami</span>-like <span class="hlt">waves</span> of non-seismic origin struck several southern European countries during the period of 23 to 27 June 2014. The event caused considerable damage from Spain to Ukraine. Here, we show that these <span class="hlt">waves</span> were long-period ocean oscillations known as meteorological <span class="hlt">tsunamis</span> which are generated by intense small-scale air pressure disturbances. An unique atmospheric synoptic pattern was tracked <span class="hlt">propagating</span> eastward over the Mediterranean and the Black seas in synchrony with onset times of observed <span class="hlt">tsunami</span> <span class="hlt">waves</span>. This pattern favoured generation and <span class="hlt">propagation</span> of atmospheric gravity <span class="hlt">waves</span> that induced pronounced <span class="hlt">tsunami</span>-like <span class="hlt">waves</span> through the Proudman resonance mechanism. This is the first documented case of a chain of destructive meteorological <span class="hlt">tsunamis</span> occurring over a distance of thousands of kilometres. Our findings further demonstrate that these events represent potentially dangerous regional phenomena and should be included in <span class="hlt">tsunami</span> warning systems. PMID:26119833</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH23A0256Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH23A0256Y"><span>Ocean-bottom pressure changes above a fault area for <span class="hlt">tsunami</span> excitation and <span class="hlt">propagation</span> observed by a submarine dense network</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yomogida, K.; Saito, T.</p> <p>2017-12-01</p> <p>Conventional <span class="hlt">tsunami</span> excitation and <span class="hlt">propagation</span> have been formulated by incompressible fluid with velocity components. This approach is valid in most cases because we usually analyze tunamis as "long gravity <span class="hlt">waves</span>" excited by submarine earthquakes. Newly developed ocean-bottom <span class="hlt">tsunami</span> networks such as S-net and DONET have dramatically changed the above situation for the following two reasons: (1) <span class="hlt">tsunami</span> <span class="hlt">propagations</span> are now directly observed in a 2-D array manner without being suffered by complex "site effects" of sea shore, and (2) initial <span class="hlt">tsunami</span> features can be directly detected just above a fault area. Removing the incompressibility assumption of sea water, we have formulated a new representation of <span class="hlt">tsunami</span> excitation based on not velocity but displacement components. As a result, not only dynamics but static term (i.e., the component of zero frequency) can be naturally introduced, which is important for the pressure observed on the ocean floor, which ocean-bottom <span class="hlt">tsunami</span> stations are going to record. The acceleration on the ocean floor should be combined with the conventional <span class="hlt">tsunami</span> height (that is, the deformation of the sea level above a given station) in the measurement of ocean-bottom pressure although the acceleration exists only during fault motions in time. The M7.2 Off Fukushima earthquake on 22 November 2016 was the first event that excited large <span class="hlt">tsunamis</span> within the territory of S-net stations. The <span class="hlt">propagation</span> of <span class="hlt">tsunamis</span> is found to be highly non-uniform, because of the strong velocity (i.e., sea depth) gradient perpendicular to the axis of Japan Trench. The earthquake was located in a shallow sea close to the coast, so that all the <span class="hlt">tsunami</span> energy is reflected by the trench region of high velocity. <span class="hlt">Tsunami</span> records (pressure gauges) within its fault area recorded clear slow motions of <span class="hlt">tsunamis</span> (i.e., sea level changes) but also large high-frequency signals, as predicted by our theoretical result. That is, it may be difficult to extract <span class="hlt">tsunami</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21148986-tsunami-wave-submerged-breakwater-interaction','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21148986-tsunami-wave-submerged-breakwater-interaction"><span>On the <span class="hlt">tsunami</span> <span class="hlt">wave</span>-submerged breakwater interaction</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Filianoti, P.; Piscopo, R.</p> <p></p> <p>The <span class="hlt">tsunami</span> <span class="hlt">wave</span> loads on a submerged rigid breakwater are inertial. It is the result arising from the simple calculation method here proposed, and it is confirmed by the comparison with results obtained by other researchers. The method is based on the estimate of the speed drop of the <span class="hlt">tsunami</span> <span class="hlt">wave</span> passing over the breakwater. The calculation is rigorous for a sinusoidal <span class="hlt">wave</span> interacting with a rigid submerged obstacle, in the framework of the linear <span class="hlt">wave</span> theory. This new approach gives a useful and simple tool for estimating <span class="hlt">tsunami</span> loads on submerged breakwaters.An unexpected novelty come out from a workedmore » example: assuming the same <span class="hlt">wave</span> height, storm <span class="hlt">waves</span> are more dangerous than <span class="hlt">tsunami</span> <span class="hlt">waves</span>, for the safety against sliding of submerged breakwaters.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li class="active"><span>2</span></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_2 --> <div id="page_3" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="41"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17..636K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17..636K"><span>Transformation of <span class="hlt">tsunami</span> <span class="hlt">waves</span> passing through the Straits of the Kuril Islands</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kostenko, Irina; Kurkin, Andrey; Pelinovsky, Efim; Zaytsev, Andrey</p> <p>2015-04-01</p> <p>Pacific ocean and themselves Kuril Islands are located in the zone of high seismic activity, where underwater earthquakes cause <span class="hlt">tsunamis</span>. They <span class="hlt">propagate</span> across Pacific ocean and penetrates into the Okhotsk sea. It is natural to expect that the Kuril Islands reflect the Okhotsk sea from the Pacific <span class="hlt">tsunami</span> <span class="hlt">waves</span>. It has long been noted that the historical <span class="hlt">tsunami</span> appeared less intense in the sea of Okhotsk in comparison with the Pacific coast of the Kuril Islands. Despite the fact that in the area of the Kuril Islands and in the Pacific ocean earthquakes with magnitude more than 8 occur, in the entire history of observations on the Okhotsk sea coast catastrophic <span class="hlt">tsunami</span> was not registered. The study of the peculiarities of the <span class="hlt">propagation</span> of historical and hypothetical <span class="hlt">tsunami</span> in the North-Eastern part of the Pacific ocean was carried out in order to identify level of effect of the Kuril Islands and Straits on them. <span class="hlt">Tsunami</span> sources were located in the Okhotsk sea and in the Pacific ocean. For this purpose, we performed a series of computational experiments using two bathymetries: 1) with use Kuril Islands; 2) without Kuril Islands. Magnitude and intensity of the <span class="hlt">tsunami</span>, obtained during numerical simulation of height, were analyzed. The simulation results are compared with the observations. Numerical experiments have shown that in the simulation without the Kuril Islands <span class="hlt">tsunamis</span> in the Okhotsk sea have higher <span class="hlt">waves</span>, and in the Central part of the sea relatively quickly damped than in fact. Based on shallow-water equation <span class="hlt">tsunami</span> numerical code NAMI DANCE was used for numerical simulations. This work was supported by ASTARTE project.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMEP14B..07S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMEP14B..07S"><span>Numerical Modelling of <span class="hlt">Tsunami</span> Generated by Deformable Submarine Slides: Parameterisation of Slide Dynamics for Coupling to <span class="hlt">Tsunami</span> <span class="hlt">Propagation</span> Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Smith, R. C.; Collins, G. S.; Hill, J.; Piggott, M. D.; Mouradian, S. L.</p> <p>2015-12-01</p> <p>Numerical modelling informs risk assessment of <span class="hlt">tsunami</span> generated by submarine slides; however, for large-scale slides modelling can be complex and computationally challenging. Many previous numerical studies have approximated slides as rigid blocks that moved according to prescribed motion. However, <span class="hlt">wave</span> characteristics are strongly dependent on the motion of the slide and previous work has recommended that more accurate representation of slide dynamics is needed. We have used the finite-element, adaptive-mesh CFD model Fluidity, to perform multi-material simulations of deformable submarine slide-generated <span class="hlt">waves</span> at real world scales for a 2D scenario in the Gulf of Mexico. Our high-resolution approach represents slide dynamics with good accuracy, compared to other numerical simulations of this scenario, but precludes tracking of <span class="hlt">wave</span> <span class="hlt">propagation</span> over large distances. To enable efficient modelling of further <span class="hlt">propagation</span> of the <span class="hlt">waves</span>, we investigate an approach to extract information about the slide evolution from our multi-material simulations in order to drive a single-layer <span class="hlt">wave</span> <span class="hlt">propagation</span> model, also using Fluidity, which is much less computationally expensive. The extracted submarine slide geometry and position as a function of time are parameterised using simple polynomial functions. The polynomial functions are used to inform a prescribed velocity boundary condition in a single-layer simulation, mimicking the effect the submarine slide motion has on the water column. The approach is verified by successful comparison of <span class="hlt">wave</span> generation in the single-layer model with that recorded in the multi-material, multi-layer simulations. We then extend this approach to 3D for further validation of this methodology (using the Gulf of Mexico scenario proposed by Horrillo et al., 2013) and to consider the effect of lateral spreading. This methodology is then used to simulate a series of hypothetical submarine slide events in the Arctic Ocean (based on evidence of historic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2013/1170/d/pdf/of2013-1170d.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2013/1170/d/pdf/of2013-1170d.pdf"><span>Modeling for the SAFRR <span class="hlt">Tsunami</span> Scenario-generation, <span class="hlt">propagation</span>, inundation, and currents in ports and harbors: Chapter D in The SAFRR (Science Application for Risk Reduction) <span class="hlt">Tsunami</span> Scenario</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>,</p> <p>2013-01-01</p> <p> locales in southern California. Importantly, section 6 provides a comparison of the effect of including horizontal displacements at the source described in section 1 and differences in bottom friction on <span class="hlt">wave</span> heights and inundation in the Ports of Los Angeles and Long Beach. Modeling described in section 7 (Lynett and Son) uses a higher order physical model to determine variations of currents during the <span class="hlt">tsunami</span> and complex flow structures such as jets and eddies. Section 7 also uses sediment transport models to estimate scour and deposition of sediment in ports and harbors—a significant effect that was observed in southern California following the 2011 Tohoku <span class="hlt">tsunami</span>. Together, all of the sections in this report form the basis for damage, impact, and emergency preparedness aspects of the SAFRR <span class="hlt">tsunami</span> scenario. Three sections of this report independently calculate <span class="hlt">wave</span> height and inundation results using the source specified by Kirby and others (2013). Refer to figure 29 in section 3, figure 52 in section 4, and figure 62 in section 6. All of these results are relative to a mean high water (MHW) vertical datum. Slight differences in the results are observed in East Basin of the Port of Los Angeles, Alamitos Bay, and the Seal Beach National Wildlife Refuge. However, given that these three modeling efforts involved different implementations of the source, different numerical <span class="hlt">wave</span> <span class="hlt">propagation</span> and runup models, and slight differences in the digital elevation models (DEMs), the similarity among the results is remarkable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-PIA04373.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-PIA04373.html"><span>Deep Ocean <span class="hlt">Tsunami</span> <span class="hlt">Waves</span> off the Sri Lankan Coast</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2005-01-26</p> <p>The initial <span class="hlt">tsunami</span> <span class="hlt">waves</span> resulting from the undersea earthquake that occurred at 00:58:53 UTC Coordinated Universal Time on 26 December 2004 off the island of Sumatra, Indonesia, as seen by NASA Terra spacecraft.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AcGeo.tmp...36A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AcGeo.tmp...36A"><span>Identifying the role of initial <span class="hlt">wave</span> parameters on <span class="hlt">tsunami</span> focusing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aydın, Baran</p> <p>2018-04-01</p> <p>Unexpected local <span class="hlt">tsunami</span> amplification, which is referred to as <span class="hlt">tsunami</span> focusing, is attributed to two different mechanisms: bathymetric features of the ocean bottom such as underwater ridges and dipolar shape of the initial <span class="hlt">wave</span> itself. In this study, we characterize the latter; that is, we explore how amplitude and location of the focusing point vary with certain geometric parameters of the initial <span class="hlt">wave</span> such as its steepness and crest length. Our results reveal two important features of <span class="hlt">tsunami</span> focusing: for mild <span class="hlt">waves</span> maximum <span class="hlt">wave</span> amplitude increases significantly with transverse length of <span class="hlt">wave</span> crest, while location of the focusing point is almost invariant. For steep <span class="hlt">waves</span>, on the other hand, increasing crest length dislocates focusing point significantly, while it causes a rather small increase in <span class="hlt">wave</span> maximum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.4765N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.4765N"><span>An Earthquake Source Sensitivity Analysis for <span class="hlt">Tsunami</span> <span class="hlt">Propagation</span> in the Eastern Mediterranean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Necmioglu, Ocal; Meral Ozel, Nurcan</p> <p>2013-04-01</p> <p>An earthquake source parameter sensitivity analysis for <span class="hlt">tsunami</span> <span class="hlt">propagation</span> in the Eastern Mediterranean has been performed based on 8 August 1303 Crete and Dodecanese Islands earthquake resulting in destructive inundation in the Eastern Mediterranean. The analysis involves 23 cases describing different sets of strike, dip, rake and focal depth, while keeping the fault area and displacement, thus the magnitude, same. The main conclusions of the evaluation are drawn from the investigation of the <span class="hlt">wave</span> height distributions at <span class="hlt">Tsunami</span> Forecast Points (TFP). The earthquake vs. initial <span class="hlt">tsunami</span> source parameters comparison indicated that the maximum initial <span class="hlt">wave</span> height values correspond in general to the changes in rake angle. No clear depth dependency is observed within the depth range considered and no strike angle dependency is observed in terms of amplitude change. Directivity sensitivity analysis indicated that for the same strike and dip, 180° shift in rake may lead to 20% change in the calculated <span class="hlt">tsunami</span> <span class="hlt">wave</span> height. Moreover, an approximately 10 min difference in the arrival time of the initial <span class="hlt">wave</span> has been observed. These differences are, however, greatly reduced in the far field. The dip sensitivity analysis, performed separately for thrust and normal faulting, has both indicated that an increase in the dip angle results in the decrease of the <span class="hlt">tsunami</span> <span class="hlt">wave</span> amplitude in the near field approximately 40%. While a positive phase shift is observed, the period and the shape of the initial <span class="hlt">wave</span> stays nearly the same for all dip angles at respective TFPs. These affects are, however, not observed at the far field. The resolution of the bathymetry, on the other hand, is a limiting factor for further evaluation. Four different cases were considered for the depth sensitivity indicating that within the depth ranges considered (15-60 km), the increase of the depth has only a smoothing effect on the synthetic <span class="hlt">tsunami</span> <span class="hlt">wave</span> height measurements at the selected TFPs. The strike</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1083297','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/servlets/purl/1083297"><span>Reconstruction of nonlinear <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Fleischer, Jason W; Barsi, Christopher; Wan, Wenjie</p> <p>2013-04-23</p> <p>Disclosed are systems and methods for characterizing a nonlinear <span class="hlt">propagation</span> environment by numerically <span class="hlt">propagating</span> a measured output waveform resulting from a known input waveform. The numerical <span class="hlt">propagation</span> reconstructs the input waveform, and in the process, the nonlinear environment is characterized. In certain embodiments, knowledge of the characterized nonlinear environment facilitates determination of an unknown input based on a measured output. Similarly, knowledge of the characterized nonlinear environment also facilitates formation of a desired output based on a configurable input. In both situations, the input thus characterized and the output thus obtained include features that would normally be lost in linear <span class="hlt">propagations</span>. Such features can include evanescent <span class="hlt">waves</span> and peripheral <span class="hlt">waves</span>, such that an image thus obtained are inherently wide-angle, farfield form of microscopy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70148278','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70148278"><span>Near-field <span class="hlt">tsunami</span> edge <span class="hlt">waves</span> and complex earthquake rupture</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, Eric L.</p> <p>2013-01-01</p> <p>The effect of distributed coseismic slip on progressive, near-field edge <span class="hlt">waves</span> is examined for continental shelf <span class="hlt">tsunamis</span>. Detailed observations of edge <span class="hlt">waves</span> are difficult to separate from the other <span class="hlt">tsunami</span> phases that are observed on tide gauge records. In this study, analytic methods are used to compute <span class="hlt">tsunami</span> edge <span class="hlt">waves</span> distributed over a finite number of modes and for uniformly sloping bathymetry. Coseismic displacements from static elastic theory are introduced as initial conditions in calculating the evolution of progressive edge-<span class="hlt">waves</span>. Both simple crack representations (constant stress drop) and stochastic slip models (heterogeneous stress drop) are tested on a fault with geometry similar to that of the M w = 8.8 2010 Chile earthquake. Crack-like ruptures that are beneath or that span the shoreline result in similar longshore patterns of maximum edge-<span class="hlt">wave</span> amplitude. Ruptures located farther offshore result in reduced edge-<span class="hlt">wave</span> excitation, consistent with previous studies. Introduction of stress-drop heterogeneity by way of stochastic slip models results in significantly more variability in longshore edge-<span class="hlt">wave</span> patterns compared to crack-like ruptures for the same offshore source position. In some cases, regions of high slip that are spatially distinct will yield sub-events, in terms of <span class="hlt">tsunami</span> generation. Constructive interference of both non-trapped and trapped <span class="hlt">waves</span> can yield significantly larger <span class="hlt">tsunamis</span> than those that produced by simple earthquake characterizations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1914824L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1914824L"><span>Joint numerical study of the 2011 Tohoku-Oki <span class="hlt">tsunami</span>: comparative <span class="hlt">propagation</span> simulations and high resolution coastal models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Loevenbruck, Anne; Arpaia, Luca; Ata, Riadh; Gailler, Audrey; Hayashi, Yutaka; Hébert, Hélène; Heinrich, Philippe; Le Gal, Marine; Lemoine, Anne; Le Roy, Sylvestre; Marcer, Richard; Pedreros, Rodrigo; Pons, Kevin; Ricchiuto, Mario; Violeau, Damien</p> <p>2017-04-01</p> <p>This study is part of the joint actions carried out within TANDEM (<span class="hlt">Tsunamis</span> in northern AtlaNtic: Definition of Effects by Modeling). This French project, mainly dedicated to the appraisal of coastal effects due to <span class="hlt">tsunami</span> <span class="hlt">waves</span> on the French coastlines, was initiated after the catastrophic 2011 Tohoku-Oki <span class="hlt">tsunami</span>. This event, which tragically struck Japan, drew the attention to the importance of <span class="hlt">tsunami</span> risk assessment, in particular when nuclear facilities are involved. As a contribution to this challenging task, the TANDEM partners intend to provide guidance for the French Atlantic area based on numerical simulation. One of the identified objectives consists in designing, adapting and validating simulation codes for <span class="hlt">tsunami</span> hazard assessment. Besides an integral benchmarking workpackage, the outstanding database of the 2011 event offers the TANDEM partners the opportunity to test their numerical tools with a real case. As a prerequisite, among the numerous published seismic source models arisen from the inversion of the various available records, a couple of coseismic slip distributions have been selected to provide common initial input parameters for the <span class="hlt">tsunami</span> computations. After possible adaptations or specific developments, the different codes are employed to simulate the Tohoku-Oki <span class="hlt">tsunami</span> from its source to the northeast Japanese coastline. The results are tested against the numerous <span class="hlt">tsunami</span> measurements and, when relevant, comparisons of the different codes are carried out. First, the results related to the oceanic <span class="hlt">propagation</span> phase are compared with the offshore records. Then, the modeled coastal impacts are tested against the onshore data. Flooding at a regional scale is considered, but high resolution simulations are also performed with some of the codes. They allow examining in detail the runup amplitudes and timing, as well as the complexity of the <span class="hlt">tsunami</span> interaction with the coastal structures. The work is supported by the Tandem project in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNH43A1726G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNH43A1726G"><span>Rapid inundation estimates at harbor scale using <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights offshore simulation and coastal amplification laws</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gailler, A.; Loevenbruck, A.; Hebert, H.</p> <p>2013-12-01</p> <p>Numerical <span class="hlt">tsunami</span> <span class="hlt">propagation</span> and inundation models are well developed and have now reached an impressive level of accuracy, especially in locations such as harbors where the <span class="hlt">tsunami</span> <span class="hlt">waves</span> are mostly amplified. In the framework of <span class="hlt">tsunami</span> warning under real-time operational conditions, the main obstacle for the routine use of such numerical simulations remains the slowness of the numerical computation, which is strengthened when detailed grids are required for the precise modeling of the coastline response of an individual harbor. Thus only <span class="hlt">tsunami</span> offshore <span class="hlt">propagation</span> modeling tools using a single sparse bathymetric computation grid are presently included within the French <span class="hlt">Tsunami</span> Warning Center (CENALT), providing rapid estimation of <span class="hlt">tsunami</span> warning at western Mediterranean and NE Atlantic basins scale. We present here a preliminary work that performs quick estimates of the inundation at individual harbors from these high sea forecasting <span class="hlt">tsunami</span> simulations. The method involves an empirical correction based on theoretical amplification laws (either Green's or Synolakis laws). The main limitation is that its application to a given coastal area would require a large database of previous observations, in order to define the empirical parameters of the correction equation. As no such data (i.e., historical tide gage records of significant <span class="hlt">tsunamis</span>) are available for the western Mediterranean and NE Atlantic basins, we use a set of synthetic mareograms, calculated for both fake and well-known historical tsunamigenic earthquakes in the area. This synthetic dataset is obtained through accurate numerical <span class="hlt">tsunami</span> <span class="hlt">propagation</span> and inundation modeling by using several nested bathymetric grids of increasingly fine resolution close to the shores (down to a grid cell size of 3m in some Mediterranean harbors). Non linear shallow water <span class="hlt">tsunami</span> modeling performed on a single 2' coarse bathymetric grid are compared to the values given by time-consuming nested grids simulations (and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA573718','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA573718"><span>Nonlinear <span class="hlt">Wave</span> <span class="hlt">Propagation</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2009-02-09</p> <p>grey) soliton , to a nearly linear wavetrain at the front moving with its group velocity ; like KdV the NLS DSW has two speeds. The 1-D NLS theory was...studies of <span class="hlt">wave</span> phenomena in nonlinear optics include ultrashort pulse dynamics in mode- locked lasers, dynamics and perturbations of dark solitons ...nonlinear Kerr response and has a large normal group - velocity dispersion (GVD). This requires a set of prisms and/or mirrors specially designed to have</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRD..122.5076L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRD..122.5076L"><span><span class="hlt">Tsunami</span>-driven gravity <span class="hlt">waves</span> in the presence of vertically varying background and tidal wind structures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Laughman, B.; Fritts, D. C.; Lund, T. S.</p> <p>2017-05-01</p> <p>Many characteristics of <span class="hlt">tsunami</span>-driven gravity <span class="hlt">waves</span> (TDGWs) enable them to easily <span class="hlt">propagate</span> into the thermosphere and ionosphere with appreciable amplitudes capable of producing detectable perturbations in electron densities and total electron content. The impact of vertically varying background and tidal wind structures on TDGW <span class="hlt">propagation</span> is investigated with a series of idealized background wind profiles to assess the relative importance of <span class="hlt">wave</span> reflection, critical-level approach, and dissipation. These numerical simulations employ a 2-D nonlinear anelastic finite-volume neutral atmosphere model which accounts for effects accompanying vertical gravity <span class="hlt">wave</span> (GW) <span class="hlt">propagation</span> such as amplitude growth with altitude. The GWs are excited by an idealized <span class="hlt">tsunami</span> forcing with a 50 cm sea surface displacement, a 400 km horizontal wavelength, and a phase speed of 200 ms-1 consistent with previous studies of the <span class="hlt">tsunami</span> generated by the 26 December 2004 Sumatra earthquake. Results indicate that rather than partial reflection and trapping, the dominant process governing TDGW <span class="hlt">propagation</span> to thermospheric altitudes is refraction to larger and smaller vertical scales, resulting in respectively larger and smaller vertical group velocities and respectively reduced and increased viscous dissipation. Under all considered background wind profiles, TDGWs were able to attain ionospheric altitudes with appreciable amplitudes. Finally, evidence of nonlinear effects is observed and the conditions leading to their formation is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH23A1870J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH23A1870J"><span>Sensitivity of <span class="hlt">Tsunami</span> <span class="hlt">Waves</span> and Coastal Inundation/Runup to Seabed Displacement Models: Application to the Cascadia Subduction zone</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jalali Farahani, R.; Fitzenz, D. D.; Nyst, M.</p> <p>2015-12-01</p> <p>Major components of <span class="hlt">tsunami</span> hazard modeling include earthquake source characterization, seabed displacement, <span class="hlt">wave</span> <span class="hlt">propagation</span>, and coastal inundation/run-up. Accurate modeling of these components is essential to identify the disaster risk exposures effectively, which would be crucial for insurance industry as well as policy makers to have <span class="hlt">tsunami</span> resistant design of structures and evacuation planning (FEMA, 2008). In this study, the sensitivity and variability of <span class="hlt">tsunami</span> coastal inundation due to Cascadia megathrust subduction earthquake are studied by considering the different approaches for seabed displacement model. The first approach is the analytical expressions that were proposed by Okada (1985, 1992) for the surface displacements and strains of rectangular sources. The second approach was introduced by Meade (2006) who introduced analytical solutions for calculating displacements, strains, and stresses on triangular sources. In this study, the seabed displacement using triangular representation of geometrically complex fault surfaces is compared with the Okada rectangular representations for the Cascadia subduction zone. In the triangular dislocation algorithm, the displacement is calculated using superposition of two angular dislocations for each of the three triangle legs. The triangular elements could give a better and gap-free representation of the fault surfaces. In addition, the rectangular representation gives large unphysical vertical displacement along the shallow-depth fault edge that generates unrealistic short-wavelength <span class="hlt">waves</span>. To study the impact of these two different algorithms on the final <span class="hlt">tsunami</span> inundation, the initial <span class="hlt">tsunami</span> <span class="hlt">wave</span> as well as <span class="hlt">wave</span> <span class="hlt">propagation</span> and the coastal inundation are simulated. To model the <span class="hlt">propagation</span> of <span class="hlt">tsunami</span> <span class="hlt">waves</span> and coastal inundation, 2D shallow water equations are modeled using the seabed displacement as the initial condition for the numerical model. <span class="hlt">Tsunami</span> numerical simulation has been performed on high</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA192104','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA192104"><span>Nonlinear <span class="hlt">Wave</span> <span class="hlt">Propagation</span>.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1987-11-23</p> <p>e.g. the Kadomtsev - Petviashvili . Davey-Stewartson, and three-<span class="hlt">wave</span> interaction equations -see for example the review [11]). little progress has been made... equations for our purposes will be the Korteweg-deVries (KdV) equation u, - 6uu., + u, =0 ( ) in one spatial dimension, and the Kadomtsev - Petviashvili (KP...similarities with KP [4] than with u, =sin u, (2) KdV (the IST for (5) has been recently considered and the Kadomtsev - Petviashvili (KP) equation in ref. [ 5</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/314105','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/314105"><span>Seismic <span class="hlt">wave</span> <span class="hlt">propagation</span> modeling</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Jones, E.M.; Olsen, K.B.</p> <p>1998-12-31</p> <p>This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). A hybrid, finite-difference technique was developed for modeling nonlinear soil amplification from three-dimensional, finite-fault radiation patters for earthquakes in arbitrary earth models. The method was applied to the 17 January 1994 Northridge earthquake. Particle velocities were computed on a plane at 5-km depth, immediately above the causative fault. Time-series of the strike-perpendicular, lateral velocities then were <span class="hlt">propagated</span> vertically in a soil column typical of the San Fernando Valley. Suitable material models were adapted from a suite used tomore » model ground motions at the US Nevada Test Site. The effects of nonlinearity reduced relative spectral amplitudes by about 40% at frequencies above 1.5 Hz but only by 10% at lower frequencies. Runs made with source-depth amplitudes increased by a factor of two showed relative amplitudes above 1.5 Hz reduced by a total of 70% above 1.5 Hz and 20% at lower frequencies. Runs made with elastic-plastic material models showed similar behavior to runs made with Masing-Rule models.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNH52A..04V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNH52A..04V"><span>CARIBE <span class="hlt">WAVE</span>/LANTEX Caribbean and Western Atlantic <span class="hlt">Tsunami</span> Exercises</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>von Hillebrandt-Andrade, C.; Whitmore, P.; Aliaga, B.; Huerfano Moreno, V.</p> <p>2013-12-01</p> <p>Over 75 <span class="hlt">tsunamis</span> have been documented in the Caribbean and Adjacent Regions over the past 500 years. While most have been generated by local earthquakes, distant generated <span class="hlt">tsunamis</span> can also affect the region. For example, <span class="hlt">waves</span> from the 1755 Lisbon earthquake and <span class="hlt">tsunami</span> were observed in Cuba, Dominican Republic, British Virgin Islands, as well as Antigua, Martinique, Guadalupe and Barbados in the Lesser Antilles. Since 1500, at least 4484 people are reported to have perished in these killer <span class="hlt">waves</span>. Although the <span class="hlt">tsunami</span> generated by the 2010 Haiti earthquake claimed only a few lives, in the 1530 El Pilar, Venezuela; 1602 Port Royale, Jamaica; 1918 Puerto Rico; and 1946 Samaná, Dominican Republic <span class="hlt">tsunamis</span> the death tolls ranged to over a thousand. Since then, there has been an explosive increase in residents, visitors, infrastructure, and economic activity along the coastlines, increasing the potential for human and economic loss. It has been estimated that on any day, upwards of more than 500,000 people could be in harm's way just along the beaches, with hundreds of thousands more working and living in the <span class="hlt">tsunamis</span> hazard zones. Given the relative infrequency of <span class="hlt">tsunamis</span>, exercises are a valuable tool to test communications, evaluate preparedness and raise awareness. Exercises in the Caribbean are conducted under the framework of the UNESCO IOC Intergovernmental Coordination Group for the <span class="hlt">Tsunami</span> and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (CARIBE EWS) and the US National <span class="hlt">Tsunami</span> Hazard Mitigation Program. On March 23, 2011, 34 countries and territories participated in the first CARIBE <span class="hlt">WAVE</span>/LANTEX regional <span class="hlt">tsunami</span> exercise, while in the second exercise on March 20, 2013 a total of 45 countries and territories participated. 481 organizations (almost 200 more than in 2011) also registered to receive the bulletins issued by the Pacific <span class="hlt">Tsunami</span> Warning Center (PTWC), West Coast and Alaska <span class="hlt">Tsunami</span> Warning Center and/or the Puerto Rico</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH51C..01H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH51C..01H"><span><span class="hlt">Tsunami</span>-Generated Atmospheric Gravity <span class="hlt">Waves</span> and Their Atmospheric and Ionospheric Effects: a Review and Some Recent Modeling Results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hickey, M. P.</p> <p>2017-12-01</p> <p><span class="hlt">Tsunamis</span> <span class="hlt">propagate</span> on the ocean surface at the shallow water phase speed which coincides with the phase speed of fast atmospheric gravity <span class="hlt">waves</span>. The forcing frequency also corresponds with those of internal atmospheric gravity <span class="hlt">waves</span>. Hence, the coupling and effective forcing of gravity <span class="hlt">waves</span> due to <span class="hlt">tsunamis</span> is particularly effective. The fast horizontal phase speeds of the resulting gravity <span class="hlt">waves</span> allows them to <span class="hlt">propagate</span> well into the thermosphere before viscous dissipation becomes strong, and the <span class="hlt">waves</span> can achieve nonlinear amplitudes at these heights resulting in large amplitude traveling ionospheric disturbances (TIDs). Additionally, because the <span class="hlt">tsunami</span> represents a moving source able to traverse large distances across the globe, the gravity <span class="hlt">waves</span> and associated TIDs can be detected at large distances from the original <span class="hlt">tsunami</span> (earthquake) source. Although it was during the mid 1970s when the <span class="hlt">tsunami</span> source of gravity <span class="hlt">waves</span> was first postulated, only relatively recently (over the last ten to fifteen years) has there has been a surge of interest in this research arena, driven largely by significant improvements in measurement technologies and computational capabilities. For example, the use of GPS measurements to derive total electron content has been a particularly powerful technique used to monitor the <span class="hlt">propagation</span> and evolution of TIDs. Monitoring airglow variations driven by atmospheric gravity <span class="hlt">waves</span> has also been a useful technique. The modeling of specific events and comparison with the observed gravity <span class="hlt">waves</span> and/or TIDs has been quite revealing. In this talk I will review some of the most interesting aspects of this research and also discuss some interesting and outstanding issues that need to be addressed. New modeling results relevant to the Tohoku <span class="hlt">tsunami</span> event will also be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28989311','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28989311"><span>Uncertainties in the 2004 Sumatra-Andaman source through nonlinear stochastic inversion of <span class="hlt">tsunami</span> <span class="hlt">waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gopinathan, D; Venugopal, M; Roy, D; Rajendran, K; Guillas, S; Dias, F</p> <p>2017-09-01</p> <p>Numerical inversions for earthquake source parameters from <span class="hlt">tsunami</span> <span class="hlt">wave</span> data usually incorporate subjective elements to stabilize the search. In addition, noisy and possibly insufficient data result in instability and non-uniqueness in most deterministic inversions, which are barely acknowledged. Here, we employ the satellite altimetry data for the 2004 Sumatra-Andaman <span class="hlt">tsunami</span> event to invert the source parameters. We also include kinematic parameters that improve the description of <span class="hlt">tsunami</span> generation and <span class="hlt">propagation</span>, especially near the source. Using a finite fault model that represents the extent of rupture and the geometry of the trench, we perform a new type of nonlinear joint inversion of the slips, rupture velocities and rise times with minimal a priori constraints. Despite persistently good waveform fits, large uncertainties in the joint parameter distribution constitute a remarkable feature of the inversion. These uncertainties suggest that objective inversion strategies should incorporate more sophisticated physical models of seabed deformation in order to significantly improve the performance of early warning systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003ASAJ..113.2186C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003ASAJ..113.2186C"><span>Chaos and <span class="hlt">wave</span> <span class="hlt">propagation</span> regimes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Colosi, John</p> <p>2003-04-01</p> <p>Ray chaos theory and parabolic equation numerical modeling were two thrusts of Fred Tappert's research that were perpetually in tension. Fred was interested in the problem of identifying <span class="hlt">wave</span> <span class="hlt">propagation</span> regimes, most notably the strong focusing caustic regime and its evolution into the saturation regime. On the one hand, chaos theory held the seed of the complexity Fred believed existed in ocean acoustic wavefields; on the other hand ocean acoustic ray chaos theory (which Fred helped to pioneer) was a disdainful approximation to the full <span class="hlt">wave</span> treatments offered by parabolic equation calculations. Fred was convinced that the saturation limit could not be obtained using ray theory and therefore he examined a new field of inquiry: a blend of chaotic ray insight and full <span class="hlt">wave</span> dynamics called <span class="hlt">wave</span> chaos. This talk will discuss some of Fred's insights on this topic and how they relate to observations from basin scale acoustic transmissions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMNH21A3830K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMNH21A3830K"><span>Influence of Earthquake Parameters on <span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Height and Inundation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kulangara Madham Subrahmanian, D.; Sri Ganesh, J.; Venkata Ramana Murthy, M.; V, R. M.</p> <p>2014-12-01</p> <p>After Indian Ocean <span class="hlt">Tsunami</span> (IOT) on 26th December, 2004, attempts are being made to assess the threat of <span class="hlt">tsunami</span> originating from different sources for different parts of India. The Andaman - Sumatra trench is segmented by transcurrent faults and differences in the rate of subduction which is low in the north and increases southward. Therefore key board model with initial deformation calculated using different strike directions, slip rates, are used. This results in uncertainties in the earthquake parameters. This study is made to identify the location of origin of most destructive <span class="hlt">tsunami</span> for Southeast coast of India and to infer the influence of the earthquake parameters in <span class="hlt">tsunami</span> <span class="hlt">wave</span> height travel time in deep ocean as well as in the shelf and inundation in the coast. Five tsunamigenic sources were considered in the Andaman - Sumatra trench taking into consideration the tectonic characters of the trench described by various authors and the modeling was carried out using TUNAMI N2 code. The model results were validated using the travel time and runup in the coastal areas and comparing the water elevation along Jason - 1's satellite track. The inundation results are compared from the field data. The assessment of the <span class="hlt">tsunami</span> threat for the area south of Chennai city the metropolitan city of South India shows that a <span class="hlt">tsunami</span> originating in Car Nicobar segment of the Andaman - Sumatra subduction zone can generate the most destructive <span class="hlt">tsunami</span>. Sensitivity analysis in the modelling indicates that fault length influences the results significantly and the <span class="hlt">tsunami</span> reaches early and with higher amplitude. Strike angle is also modifying the <span class="hlt">tsunami</span> followed by amount of slip.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_3 --> <div id="page_4" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="61"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH23A0205S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH23A0205S"><span>How Perturbing Ocean Floor Disturbs <span class="hlt">Tsunami</span> <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Salaree, A.; Okal, E.</p> <p>2017-12-01</p> <p>Bathymetry maps play, perhaps the most crucial role in optimal <span class="hlt">tsunami</span> simulations. Regardless of the simulation method, on one hand, it is desirable to include every detailed bathymetry feature in the simulation grids in order to predict <span class="hlt">tsunami</span> amplitudes as accurately as possible, but on the other hand, large grids result in long simulation times. It is therefore, of interest to investigate a "sufficiency" level - if any - for the amount of details in bathymetry grids needed to reconstruct the most important features in <span class="hlt">tsunami</span> simulations, as obtained from the actual bathymetry. In this context, we use a spherical harmonics series approach to decompose the bathymetry of the Pacific ocean into its components down to a resolution of 4 degrees (l=100) and create bathymetry grids by accumulating the resulting terms. We then use these grids to simulate the <span class="hlt">tsunami</span> behavior from pure thrust events around the Pacific through the MOST algorithm (e.g. Titov & Synolakis, 1995; Titov & Synolakis, 1998). Our preliminary results reveal that one would only need to consider the sum of the first 40 coefficients (equivalent to a resolution of 1000 km) to reproduce the main components of the "real" results. This would result in simpler simulations, and potentially allowing for more efficient <span class="hlt">tsunami</span> warning algorithms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.8859G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.8859G"><span>Rapid inundation estimates at harbor scale using <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights offshore simulation and Green's law approach</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gailler, Audrey; Hébert, Hélène; Loevenbruck, Anne</p> <p>2013-04-01</p> <p>Improvements in the availability of sea-level observations and advances in numerical modeling techniques are increasing the potential for <span class="hlt">tsunami</span> warnings to be based on numerical model forecasts. Numerical <span class="hlt">tsunami</span> <span class="hlt">propagation</span> and inundation models are well developed and have now reached an impressive level of accuracy, especially in locations such as harbors where the <span class="hlt">tsunami</span> <span class="hlt">waves</span> are mostly amplified. In the framework of <span class="hlt">tsunami</span> warning under real-time operational conditions, the main obstacle for the routine use of such numerical simulations remains the slowness of the numerical computation, which is strengthened when detailed grids are required for the precise modeling of the coastline response on the scale of an individual harbor. In fact, when facing the problem of the interaction of the <span class="hlt">tsunami</span> wavefield with a shoreline, any numerical simulation must be performed over an increasingly fine grid, which in turn mandates a reduced time step, and the use of a fully non-linear code. Such calculations become then prohibitively time-consuming, which is clearly unacceptable in the framework of real-time warning. Thus only <span class="hlt">tsunami</span> offshore <span class="hlt">propagation</span> modeling tools using a single sparse bathymetric computation grid are presently included within the French <span class="hlt">Tsunami</span> Warning Center (CENALT), providing rapid estimation of <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights in high seas, and <span class="hlt">tsunami</span> warning maps at western Mediterranean and NE Atlantic basins scale. We present here a preliminary work that performs quick estimates of the inundation at individual harbors from these deep <span class="hlt">wave</span> heights simulations. The method involves an empirical correction relation derived from Green's law, expressing conservation of <span class="hlt">wave</span> energy flux to extend the gridded <span class="hlt">wave</span> field into the harbor with respect to the nearby deep-water grid node. The main limitation of this method is that its application to a given coastal area would require a large database of previous observations, in order to define the empirical</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.6352K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.6352K"><span><span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Bimodular Geomaterials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kuznetsova, Maria; Pasternak, Elena; Dyskin, Arcady; Pelinovsky, Efim</p> <p>2016-04-01</p> <p>Observations and laboratory experiments show that fragmented or layered geomaterials have the mechanical response dependent on the sign of the load. The most adequate model accounting for this effect is the theory of bimodular (bilinear) elasticity - a hyperelastic model with different elastic moduli for tension and compression. For most of geo- and structural materials (cohesionless soils, rocks, concrete, etc.) the difference between elastic moduli is such that their modulus in compression is considerably higher than that in tension. This feature has a profound effect on oscillations [1]; however, its effect on <span class="hlt">wave</span> <span class="hlt">propagation</span> has not been comprehensively investigated. It is believed that incorporation of bilinear elastic constitutive equations within theory of <span class="hlt">wave</span> dynamics will bring a deeper insight to the study of mechanical behaviour of many geomaterials. The aim of this paper is to construct a mathematical model and develop analytical methods and numerical algorithms for analysing <span class="hlt">wave</span> <span class="hlt">propagation</span> in bimodular materials. Geophysical and exploration applications and applications in structural engineering are envisaged. The FEM modelling of <span class="hlt">wave</span> <span class="hlt">propagation</span> in a 1D semi-infinite bimodular material has been performed with the use of Marlow potential [2]. In the case of the initial load expressed by a harmonic pulse loading strong dependence on the pulse sign is observed: when tension is applied before compression, the phenomenon of disappearance of negative (compressive) strains takes place. References 1. Dyskin, A., Pasternak, E., & Pelinovsky, E. (2012). Periodic motions and resonances of impact oscillators. Journal of Sound and Vibration, 331(12), 2856-2873. 2. Marlow, R. S. (2008). A Second-Invariant Extension of the Marlow Model: Representing Tension and Compression Data Exactly. In ABAQUS Users' Conference.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH23A0202N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH23A0202N"><span>A rapid calculation system for <span class="hlt">tsunami</span> <span class="hlt">propagation</span> in Japan by using the AQUA-MT/CMT solutions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nakamura, T.; Suzuki, W.; Yamamoto, N.; Kimura, H.; Takahashi, N.</p> <p>2017-12-01</p> <p>We developed a rapid calculation system of geodetic deformations and <span class="hlt">tsunami</span> <span class="hlt">propagation</span> in and around Japan. The system automatically conducts their forward calculations by using point source parameters estimated by the AQUA system (Matsumura et al., 2006), which analyze magnitude, hypocenter, and moment tensors for an event occurring in Japan in 3 minutes of the origin time at the earliest. An optimized calculation code developed by Nakamura and Baba (2016) is employed for the calculations on our computer server with 12 core processors of Intel Xeon 2.60 GHz. Assuming a homogeneous fault slip in the single fault plane as the source fault, the developed system calculates each geodetic deformation and <span class="hlt">tsunami</span> <span class="hlt">propagation</span> by numerically solving the 2D linear long-<span class="hlt">wave</span> equations for the grid interval of 1 arc-min from two fault orientations simultaneously; i.e., one fault and its conjugate fault plane. Because fault models based on moment tensor analyses of event data are used, the system appropriately evaluate <span class="hlt">tsunami</span> <span class="hlt">propagation</span> even for unexpected events such as normal faulting in the subduction zone, which differs with the evaluation of <span class="hlt">tsunami</span> arrivals and heights from a pre-calculated database by using fault models assuming typical types of faulting in anticipated source areas (e.g., Tatehata, 1998; Titov et al., 2005; Yamamoto et al., 2016). By the complete automation from event detection to output graphical figures, the calculation results can be available via e-mail and web site in 4 minutes of the origin time at the earliest. For moderate-sized events such as M5 to 6 events, the system helps us to rapidly investigate whether amplitudes of <span class="hlt">tsunamis</span> at nearshore and offshore stations exceed a noise level or not, and easily identify actual <span class="hlt">tsunamis</span> at the stations by comparing with obtained synthetic waveforms. In the case of using source models investigated from GNSS data, such evaluations may be difficult because of the low resolution of sources due to a low</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNH41B1723W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNH41B1723W"><span><span class="hlt">Tsunami</span> Hockey</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weinstein, S.; Becker, N. C.; Wang, D.; Fryer, G. J.</p> <p>2013-12-01</p> <p>An important issue that vexes <span class="hlt">tsunami</span> warning centers (TWCs) is when to cancel a <span class="hlt">tsunami</span> warning once it is in effect. Emergency managers often face a variety of pressures to allow the public to resume their normal activities, but allowing coastal populations to return too quickly can put them at risk. A TWC must, therefore, exercise caution when cancelling a warning. Kim and Whitmore (2013) show that in many cases a TWC can use the decay of <span class="hlt">tsunami</span> oscillations in a harbor to forecast when its amplitudes will fall to safe levels. This technique should prove reasonably robust for local <span class="hlt">tsunamis</span> (those that are potentially dangerous within only 100 km of their source region) and for regional <span class="hlt">tsunamis</span> (whose danger is limited to within 1000km of the source region) as well. For ocean-crossing destructive <span class="hlt">tsunamis</span> such as the 11 March 2011 Tohoku <span class="hlt">tsunami</span>, however, this technique may be inadequate. When a <span class="hlt">tsunami</span> <span class="hlt">propagates</span> across the ocean basin, it will encounter topographic obstacles such as seamount chains or coastlines, resulting in coherent reflections that can <span class="hlt">propagate</span> great distances. When these reflections reach previously-impacted coastlines, they can recharge decaying <span class="hlt">tsunami</span> oscillations and make them hazardous again. Warning center scientists should forecast sea-level records for 24 hours beyond the initial <span class="hlt">tsunami</span> arrival in order to observe any potential reflections that may pose a hazard. Animations are a convenient way to visualize reflections and gain a broad geographic overview of their impacts. The Pacific <span class="hlt">Tsunami</span> Warning Center has developed tools based on <span class="hlt">tsunami</span> simulations using the RIFT <span class="hlt">tsunami</span> forecast model. RIFT is a linear, parallelized numerical <span class="hlt">tsunami</span> <span class="hlt">propagation</span> model that runs very efficiently on a multi-CPU system (Wang et al, 2012). It can simulate 30-hours of <span class="hlt">tsunami</span> <span class="hlt">wave</span> <span class="hlt">propagation</span> in the Pacific Ocean at 4 arc minute resolution in approximately 6 minutes of real time on a 12-CPU system. Constructing a 30-hour animation using 1</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRC..123.2965T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRC..123.2965T"><span><span class="hlt">Tsunami</span> <span class="hlt">Waves</span> and <span class="hlt">Tsunami</span>-Induced Natural Oscillations Determined by HF Radar in Ise Bay, Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Toguchi, Y.; Fujii, S.; Hinata, H.</p> <p>2018-04-01</p> <p><span class="hlt">Tsunami</span> <span class="hlt">waves</span> and the subsequent natural oscillations generated by the 2011 Tohoku earthquake were observed by two high-frequency (HF) radars and four tidal gauge records in Ise Bay. The radial velocity components of both records increased abruptly at approximately 17:00 (JST) and continued for more than 24 h. This indicated that natural oscillations followed the <span class="hlt">tsunami</span> in Ise Bay. The spectral analyses showed that the <span class="hlt">tsunami</span> <span class="hlt">wave</span> arrivals had periods of 16-19, 30-40, 60-90, and 120-140 min. The three longest periods were remarkably amplified. Time-frequency analysis also showed the energy increase and duration of these periods. We used an Empirical Orthogonal Function (EOF) to analyze the total velocity of the currents to find the underlying oscillation patterns in the three longest periods. To verify the physical properties of the EOF analysis results, we calculated the oscillation modes in Ise Bay using a numerical model proposed by Loomis. The results of EOF analysis showed that the oscillation modes of 120-140 and 60-90 min period bands were distributed widely, whereas the oscillation mode of the 30-40 min period band was distributed locally. The EOF spatial patterns of each period showed good agreement with the eigenmodes calculated by the method of Loomis (1975). Thus, the HF radars were capable of observing the <span class="hlt">tsunami</span> arrival and the subsequent oscillations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUFM.S51D1034L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUFM.S51D1034L"><span>High-Performance Computing and Visualization of <span class="hlt">Tsunamis</span> and Wind-Driven <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Y. S.; Zhang, H.; Yuen, D. A.; Wang, M.</p> <p>2005-12-01</p> <p>The Sumatran earthquake and the <span class="hlt">tsunami</span> <span class="hlt">waves</span> produced have awakened great scientific interest in <span class="hlt">wave-propagation</span> over undulated bottom topography and along complicated coastlines. The recent hurricane Katrina has also called our attention to shorter period <span class="hlt">waves</span> near the coast. Analytical approximations are valid over long wavelengths in the far field. For near field regions with complex geography and other complications, such as islands and harbors, numerical simulations must be employed to obtain accurate predictions in time and space. Nowadays using 10**7 to 10**8 grid points become quite routine with massively parallel computers and large RAM and disk memories. Besides <span class="hlt">tsunamis</span>, river discharges from upstream events and <span class="hlt">waves</span> driven by hurricanes are also of societal relevance, especially in central China and now also in U.S.A. Using automatic grid generation methods, we have devised a finite-element based code, for the three stages which culminates with the use of the augmented Lagrangian method for the run-up process, as well as the Arbitrary Lagrange- Euler Configuration method to tackle the free surface problem near the seashore. This formulation allows for the <span class="hlt">wave</span> surface to be self-consistently determined within a linearized framework and is computationally very fast. Our continuous efforts are focussed on seeking novel algorithms and state of art techniques, in order to unravel the mysteries associated with <span class="hlt">tsunami</span> <span class="hlt">wave</span> <span class="hlt">propagation</span> and wind-driven <span class="hlt">waves</span> in 3-D. We have cast the Navier-Stokes equations within the framework of a compressible model with an equation of state for sea-water. Our formulation allows the tracking and simulation of three stages , principally the formation, <span class="hlt">propagation</span> and run-up stages of <span class="hlt">tsunami</span> and <span class="hlt">waves</span> coming ashore. The sequential version of this code can run on a workstation with 4 Gbyte memory less than 2 minutes per time step for one million grid points. This code has also been parallelized with MPI-2 and has good</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.4271R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.4271R"><span>A Global Sensitivity Analysis Method on Maximum <span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Heights to Potential Seismic Source Parameters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ren, Luchuan</p> <p>2015-04-01</p> <p>A Global Sensitivity Analysis Method on Maximum <span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Heights to Potential Seismic Source Parameters Luchuan Ren, Jianwei Tian, Mingli Hong Institute of Disaster Prevention, Sanhe, Heibei Province, 065201, P.R. China It is obvious that the uncertainties of the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights in offshore area are partly from uncertainties of the potential seismic <span class="hlt">tsunami</span> source parameters. A global sensitivity analysis method on the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights to the potential seismic source parameters is put forward in this paper. The <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights are calculated by COMCOT ( the Cornell Multi-grid Coupled <span class="hlt">Tsunami</span> Model), on the assumption that an earthquake with magnitude MW8.0 occurred at the northern fault segment along the Manila Trench and triggered a <span class="hlt">tsunami</span> in the South China Sea. We select the simulated results of maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights at specific sites in offshore area to verify the validity of the method proposed in this paper. For ranking importance order of the uncertainties of potential seismic source parameters (the earthquake's magnitude, the focal depth, the strike angle, dip angle and slip angle etc..) in generating uncertainties of the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights, we chose Morris method to analyze the sensitivity of the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights to the aforementioned parameters, and give several qualitative descriptions of nonlinear or linear effects of them on the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights. We quantitatively analyze the sensitivity of the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights to these parameters and the interaction effects among these parameters on the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights by means of the extended FAST method afterward. The results shows that the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights are very sensitive to the earthquake magnitude, followed successively by the epicenter location, the strike angle and dip angle, the interactions effect between the sensitive parameters are very obvious at specific site in offshore area, and there</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH43B1857M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH43B1857M"><span>Modeling <span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Generation Using a Two-layer Granular Landslide Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ma, G.; Kirby, J. T., Jr.; Shi, F.; Grilli, S. T.; Hsu, T. J.</p> <p>2016-12-01</p> <p><span class="hlt">Tsunamis</span> can be generated by subaerial or submarine landslides in reservoirs, lakes, fjords, bays and oceans. Compared to seismogenic <span class="hlt">tsunamis</span>, landslide or submarine mass failure (SMF) <span class="hlt">tsunamis</span> are normally characterized by relatively shorter <span class="hlt">wave</span> lengths and stronger <span class="hlt">wave</span> dispersion, and potentially may generate large <span class="hlt">wave</span> amplitudes locally and high run-up along adjacent coastlines. Due to a complex interplay between the landslide and <span class="hlt">tsunami</span> <span class="hlt">waves</span>, accurate simulation of landslide motion as well as <span class="hlt">tsunami</span> generation is a challenging task. We develop and test a new two-layer model for granular landslide motion and <span class="hlt">tsunami</span> <span class="hlt">wave</span> generation. The landslide is described as a saturated granular flow, accounting for intergranular stresses governed by Coulomb friction. <span class="hlt">Tsunami</span> <span class="hlt">wave</span> generation is simulated by the three-dimensional non-hydrostatic <span class="hlt">wave</span> model NHWAVE, which is capable of capturing <span class="hlt">wave</span> dispersion efficiently using a small number of discretized vertical levels. Depth-averaged governing equations for the granular landslide are derived in a slope-oriented coordinate system, taking into account the dynamic interaction between the lower-layer granular landslide and upper-layer water motion. The model is tested against laboratory experiments on impulsive <span class="hlt">wave</span> generation by subaerial granular landslides. Model results illustrate a complex interplay between the granular landslide and <span class="hlt">tsunami</span> <span class="hlt">waves</span>, and they reasonably predict not only the <span class="hlt">tsunami</span> <span class="hlt">wave</span> generation but also the granular landslide motion from initiation to deposition.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSPO12A..03M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSPO12A..03M"><span>Modeling the <span class="hlt">propagation</span>, transformation and the impact of <span class="hlt">tsunami</span> on urban areas using the coupling STOC-ML/IC/CADMAS in nested grids - Application to specific sites of Chile to improve the <span class="hlt">tsunami</span> induced loads prediction.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mokrani, C.; Catalan, P. A.; Cienfuegos, R.; Arikawa, T.</p> <p>2016-02-01</p> <p>A large part of coasts around the world are affected by <span class="hlt">tsunami</span> impacts, which supposes a challenge when designing coastal protection structures. Numerical models provide predictions of <span class="hlt">tsunami</span>-induced loads and there time evolution, which can be used to improve sizing rules of coastal structures. However, the numerical assessment of impact loads is an hard stake. Indeed, recent experimental studies have shown that pressure dynamics generated during <span class="hlt">tsunami</span> impacts are highly sensitive to the incident local shape of the <span class="hlt">tsunami</span>. Therefore, high numerical resolutions and very accurate models are required to model all stages during which the <span class="hlt">tsunami</span> shape is modified before the impact. Given the large distances involved in <span class="hlt">tsunami</span> events, this can be disregarded in favor of computing time. The Port and Airport Research Institute (PARI) has recently developed a three-way coupled model which allows to accurately model the incident <span class="hlt">tsunami</span> shape while maintaining reasonable computational time. This coupling approach uses three models used in nested grids (cf. Figure 1). The first one (STOC-ML) solves Nonlinear Shallow Water Equations with hydrostatic pressure. It is used to model the <span class="hlt">tsunami</span> <span class="hlt">propagation</span> off the coast. The second one (STOC-IC) is a 3D non-hydrostatic model, on which the free-surface position is estimated through the integrated continuity equation. It has shown to accurately describe dispersive and weakly linear effects occurring at the coast vicinity. The third model (CADMAS-SURF) solves fully three-dimensional Navier-Stokes equations and use a VOF method. Highly nonlinear, dispersive effects and <span class="hlt">wave</span> breaking processes can be included at the <span class="hlt">wave</span> scale and therefore, a very accurate description of the incident <span class="hlt">tsunami</span> is provided. Each model have been separately validated from analytical and/or experimental data. The present objective is to highlight recent advances in Coastal Ocean modeling for <span class="hlt">tsunami</span> modeling and loads prediction by applying this</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JIEIC..97..493A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JIEIC..97..493A"><span>New Offshore Approach to Reduce Impact of <span class="hlt">Tsunami</span> <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anant Chatorikar, Kaustubh</p> <p>2016-07-01</p> <p>The world is facing an increasing frequency and intensity of natural disaster that has devastating impacts on society. As per International Strategy for Disaster Reduction (ISDR), it has been observed that over five million people were killed or affected in last 10 years and huge amount of economic losses occurred due to natural disaster. The 2011 <span class="hlt">tsunami</span> in Japan showed a tremendous setback to existing technology of <span class="hlt">tsunami</span> protection. More than 25,000 lives have been lost, Apart from that the damage to the nuclear power stations has severely affected the nearby populace and marine life. After the 2004 <span class="hlt">tsunami</span>, world's effort has been concentrated on early warning and effective mitigation plans to defend against <span class="hlt">tsunami</span>. It is anybody's guess as to what would have happened if such natural calamity specifically <span class="hlt">tsunami</span> of such magnitude strikes our nation as country has already suffered from it in 2004 and seen its disastrous effects. But the point is what if such calamity strikes the mega cities like Chennai, Mumbai and Kolkata again where there is extensive human habitation and conventional warning systems and mitigation methods are not effective when it comes to huge population of these cities, destruction caused by it will be worse than nuclear weapon strike as there is also very high possibility of deaths due to stampede. This paper talks about an idea inspired from daily routine and its relation with fundamental physics as well as method of its deployment is discussed. According to this idea when <span class="hlt">wave</span> will strike the coast, aim is not to stop it but to reduce its impact within the permissible impact limits of existing infrastructure by converting it into foam <span class="hlt">wave</span> with help of surfactants, thereby saving human lives as well as complications of Mitigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/103551-propagation-fluidization-combustion-wave','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/103551-propagation-fluidization-combustion-wave"><span><span class="hlt">Propagation</span> of a fluidization - combustion <span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pron, G.P.; Gusachenko, L.K.; Zarko, V.E.</p> <p>1994-05-01</p> <p>A fluidization-combustion <span class="hlt">wave</span> <span class="hlt">propagating</span> through a fixed and initially cool bed was created by igniting coal at the top surface of the bed. The proposed physical interpretation of the phenomenon is in qualitative agreement with the experimental dependences of the characteristics of the process on determining parameters. A kindling regime with forced <span class="hlt">wave</span> <span class="hlt">propagation</span> is suggested.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DFDD14007P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DFDD14007P"><span>Generation of realistic <span class="hlt">tsunami</span> <span class="hlt">waves</span> using a bottom-tilting <span class="hlt">wave</span> maker</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Park, Yong Sung; Hwang, Jin Hwan</p> <p>2016-11-01</p> <p><span class="hlt">Tsunamis</span> have caused more than 260,000 human losses and 250 billion in damage worldwide in the last ten years. Observations made during 2011 Japan Tohoku <span class="hlt">Tsunami</span> revealed that the commonly used <span class="hlt">waves</span> (solitary <span class="hlt">waves</span>) to model <span class="hlt">tsunamis</span> are at least an order-of-magnitude shorter than the real <span class="hlt">tsunamis</span>, which calls for re-evaluation of the current understanding of <span class="hlt">tsunamis</span>. To prompt the required paradigm shift, a new <span class="hlt">wave</span> generator, namely the bottom-tilting <span class="hlt">wave</span> generator, has been developed at the University of Dundee. The <span class="hlt">wave</span> tank is fitted with an adjustable slope and a bottom flap hinged at the beginning of the slope. By moving the bottom flap up and down, we can generate very long <span class="hlt">waves</span>. Here we will report characteristics of <span class="hlt">waves</span> generated by simple bottom motions, either moving it upward or downward from an initial displacement ending it being horizontal. Two parameters, namely the initial displacement of the bottom and the speed of the motion, determine characteristics of the generated <span class="hlt">waves</span>. <span class="hlt">Wave</span> amplitudes scale well with the volume flux of the displaced water. On the other hand, due to combined effects of nonlinearity and dispersion, wavelengths show more complicated relationship with the two bottom motion parameters. We will also demonstrate that by combining simple up and down motions, it is possible to generate <span class="hlt">waves</span> resembling the one measured during 2011 <span class="hlt">tsunami</span>. YSP acknowledges financial support from the Royal Society of Edinburgh through the Royal Society of Edinburgh and Scottish Government Personal Research Fellowship Co-Funded by the Marie-Curie Actions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890011928','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890011928"><span>Sedimentological effects of <span class="hlt">tsunamis</span>, with particular reference to impact-generated and volcanogenic <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bourgeois, Joanne; Wiberg, Patricia L.</p> <p>1988-01-01</p> <p>Impulse-generated <span class="hlt">waves</span> (<span class="hlt">tsunamis</span>) may be produced, at varying scales and global recurrence intervals (RI), by several processes. Meteorite-water impacts will produce <span class="hlt">tsunamis</span>, and asteroid-scale impacts with associated mega-<span class="hlt">tsunamis</span> may occur. A bolide-water impact would undoubtedly produce a major <span class="hlt">tsunami</span>, whose sedimentological effects should be recognizable. Even a bolide-land impact might trigger major submarine landslides and thus <span class="hlt">tsunamis</span>. In all posulated scenarios for the K/T boundary event, then, <span class="hlt">tsunamis</span> are expected, and where to look for them must be determined, and how to distinguish deposits from different <span class="hlt">tsunamis</span>. Also, because <span class="hlt">tsunamis</span> decrease in height as they move away from their source, the proximal effects will differ by perhaps orders of magnitude from distal effects. Data on the characteristics of <span class="hlt">tsunamis</span> at their origin are scarce. Some observations exist for <span class="hlt">tsunamis</span> generated by thermonuclear explosions and for seismogenic <span class="hlt">tsunamis</span>, and experimental work was conducted on impact-generated <span class="hlt">tsunamis</span>. All <span class="hlt">tsunamis</span> of interest have <span class="hlt">wave</span>-lengths of 0(100) km and thus behave as shallow-water <span class="hlt">waves</span> in all ocean depths. Typical <span class="hlt">wave</span> periods are 0(10 to 100) minutes. The effect of these <span class="hlt">tsunamis</span> can be estimated in the marine and coastal realm by calculating boundary shear stresses (expressed as U*, the shear velocity). An event layer at the K/T boundary in Texas occurs in mid-shelf muds. Only a large, long-period <span class="hlt">wave</span> with a <span class="hlt">wave</span> height of 0(50) m, is deemed sufficient to have produced this layer. Such <span class="hlt">wave</span> heights imply a nearby volcanic explosion on the scale of Krakatau or larger, or a nearby submarine landslide also of great size, or a bolide-water impact in the ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH53D..03B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH53D..03B"><span>Applications of acoustic-gravity <span class="hlt">waves</span> numerical modeling to <span class="hlt">tsunami</span> signals observed by gravimetry satellites in very low orbit</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brissaud, Q.; Garcia, R.; Sladen, A.; Martin, R.; Komatitsch, D.</p> <p>2016-12-01</p> <p>Acoustic and gravity <span class="hlt">waves</span> <span class="hlt">propagating</span> in planetary atmospheres have been studied intensively as markers of specific phenomena (tectonic events, explosions) or as contributors to atmosphere dynamics. To get a better understanding of the physics behind these dynamic processes, both acoustic and gravity <span class="hlt">waves</span> <span class="hlt">propagation</span> should be modeled in an attenuating and windy 3D atmosphere from the ground all the way to the upper thermosphere. Thus, in order to provide an efficient numerical tool at the regional or global scale we introduce a high-order finite-difference time domain (FDTD) approach that relies on the linearized compressible Navier-Stokes equations with spatially non constant physical parameters (density, viscosities and speed of sound) and background velocities (wind). We present applications of these simulations to the <span class="hlt">propagation</span> of gravity <span class="hlt">waves</span> generated by <span class="hlt">tsunamis</span> for realistic cases for which atmospheric models are extracted from empirical models including variations with altitude of atmospheric parameters, and <span class="hlt">tsunami</span> forcing at the ocean surface is extracted from shallow water simulations. We describe the specific difficulties induced by the size of the simulation, the boundary conditions and the spherical geometry and compare the simulation outputs to data gathered by gravimetric satellites crossing gravity <span class="hlt">waves</span> generated by <span class="hlt">tsunamis</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.6375K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.6375K"><span>Fast algorithm for calculation of the moving <span class="hlt">tsunami</span> <span class="hlt">wave</span> height</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Krivorotko, Olga; Kabanikhin, Sergey</p> <p>2014-05-01</p> <p>One of the most urgent problems of mathematical <span class="hlt">tsunami</span> modeling is estimation of a <span class="hlt">tsunami</span> <span class="hlt">wave</span> height while a <span class="hlt">wave</span> approaches to the coastal zone. There are two methods for solving this problem, namely, Airy-Green formula in one-dimensional case ° --- S(x) = S(0) 4 H(0)/H (x), and numerical solution of an initial-boundary value problem for linear shallow water equations ( { ηtt = div (gH (x,y)gradη), (x,y,t) ∈ ΩT := Ω ×(0,T); ( η|t=0 = q(x,y), ηt|t=0 = 0, (x,y ) ∈ Ω := (0,Lx)× (0,Ly ); (1) η|δΩT = 0. Here η(x,y,t) is the free water surface vertical displacement, H(x,y) is the depth at point (x,y), q(x,y) is the initial amplitude of a <span class="hlt">tsunami</span> <span class="hlt">wave</span>, S(x) is a moving <span class="hlt">tsunami</span> <span class="hlt">wave</span> height at point x. The main difficulty problem of <span class="hlt">tsunami</span> modeling is a very big size of the computational domain ΩT. The calculation of the function η(x,y,t) of three variables in ΩT requires large computing resources. We construct a new algorithm to solve numerically the problem of determining the moving <span class="hlt">tsunami</span> <span class="hlt">wave</span> height which is based on kinematic-type approach and analytical representation of fundamental solution (2). The <span class="hlt">wave</span> is supposed to be generated by the seismic fault of the bottom η(x,y,0) = g(y) ·θ(x), where θ(x) is a Heaviside theta-function. Let τ(x,y) be a solution of the eikonal equation 1 τ2x +τ2y = --, gH (x,y) satisfying initial conditions τ(0,y) = 0 and τx(0,y) = (gH (0,y))-1/2. Introducing new variables and new functions: ° -- z = τ(x,y), u(z,y,t) = ηt(x,y,t), b(z,y) = gH(x,y). We obtain an initial-boundary value problem in new variables from (1) ( 2 2 (2 bz- ) { utt = uzz + b uyy + 2b τyuzy + b(τxx + τyy) + 2b + 2bbyτy uz+ ( +2b(bzτy + by)uy, z,y- >2 0,t > 0,2 -1/2 u|t 0,t > 0. Then after some mathematical transformation we get the structure of the function u(x,y,t) in the form u(z,y,t) = S(z,y)·θ(t - z) + ˜u(z,y,t). (2) Here Å©(z,y,t) is a smooth function, S(z,y) is the solution of the problem: { S + b2τ S + (1b2(τ +</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S21A4412H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S21A4412H"><span>Web-based <span class="hlt">Tsunami</span> Early Warning System with instant <span class="hlt">Tsunami</span> <span class="hlt">Propagation</span> Calculations in the GPU Cloud</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hammitzsch, M.; Spazier, J.; Reißland, S.</p> <p>2014-12-01</p> <p>Usually, <span class="hlt">tsunami</span> early warning and mitigation systems (TWS or TEWS) are based on several software components deployed in a client-server based infrastructure. The vast majority of systems importantly include desktop-based clients with a graphical user interface (GUI) for the operators in early warning centers. However, in times of cloud computing and ubiquitous computing the use of concepts and paradigms, introduced by continuously evolving approaches in information and communications technology (ICT), have to be considered even for early warning systems (EWS). Based on the experiences and the knowledge gained in three research projects - 'German Indonesian <span class="hlt">Tsunami</span> Early Warning System' (GITEWS), 'Distant Early Warning System' (DEWS), and 'Collaborative, Complex, and Critical Decision-Support in Evolving Crises' (TRIDEC) - new technologies are exploited to implement a cloud-based and web-based prototype to open up new prospects for EWS. This prototype, named 'TRIDEC Cloud', merges several complementary external and in-house cloud-based services into one platform for automated background computation with graphics processing units (GPU), for web-mapping of hazard specific geospatial data, and for serving relevant functionality to handle, share, and communicate threat specific information in a collaborative and distributed environment. The prototype in its current version addresses <span class="hlt">tsunami</span> early warning and mitigation. The integration of GPU accelerated <span class="hlt">tsunami</span> simulation computations have been an integral part of this prototype to foster early warning with on-demand <span class="hlt">tsunami</span> predictions based on actual source parameters. However, the platform is meant for researchers around the world to make use of the cloud-based GPU computation to analyze other types of geohazards and natural hazards and react upon the computed situation picture with a web-based GUI in a web browser at remote sites. The current website is an early alpha version for demonstration purposes to give the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNH41B1711W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNH41B1711W"><span>Developing a global <span class="hlt">tsunami</span> <span class="hlt">propagation</span> database and its application for coastal hazard assessments in China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, N.; Tang, L.; Titov, V.; Newman, J. C.; Dong, S.; Wei, Y.</p> <p>2013-12-01</p> <p>The tragedies of the 2004 Indian Ocean and 2011 Japan <span class="hlt">tsunamis</span> have increased awareness of <span class="hlt">tsunami</span> hazards for many nations, including China. The low land level and high population density of China's coastal areas place it at high risk for <span class="hlt">tsunami</span> hazards. Recent research (Komatsubara and Fujiwara, 2007) highlighted concerns of a magnitude 9.0 earthquake on the Nankai trench, which may affect China's coasts not only in South China Sea, but also in the East Sea and Yellow Sea. Here we present our work in progress towards developing a global <span class="hlt">tsunami</span> <span class="hlt">propagation</span> database that can be used for hazard assessments by many countries. The <span class="hlt">propagation</span> scenarios are computed by using NOAA's MOST numerical model. Each scenario represents a typical Mw 7.5 earthquake with predefined earthquake parameters (Gica et al., 2008). The model grid was interpolated from ETOPO1 at 4 arc-min resolution, covering -80° to72°N and 0 to 360°E. We use this database for preliminary <span class="hlt">tsunami</span> hazard assessment along China's coastlines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhDT........24C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhDT........24C"><span><span class="hlt">Wave</span> <span class="hlt">Propagation</span> inside Random Media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cheng, Xiaojun</p> <p></p> <p> =-x/l where l is the transport mean free path. The result does not depend on the sample length, which is counterintuitive yet remarkably simple. More supprisingly, the linear fall-off of energy profile holds for totally disordered random 1D layered samples in simulations where the LDOS is uniform as well as for single mode random waveguide experiments and 1D nearly periodic samples where the LDOS is suppressed in the middle of the sample. The generalization of the transmission matrix to the interior of quasi-1D random samples, which is defined as the field matrix, and its eigenvalues statistics are also discussed. The maximum energy deposition at a location is not the intensity of the first transmission eigenchannel but the eigenvalue of the first energy density eigenchannels at that cross section, which can be much greater than the average value. The contrast, which is the ratio of the intensity at the focused point to the background intensity, in optimal focusing is determined by the participation number of the energy density eigenvalues and its inverse gives the variance of the energy density at that cross section in a single configuration. We have also studied topological states in photonic structures. We have demonstrated robust <span class="hlt">propagation</span> of electromagnetic <span class="hlt">waves</span> along reconfigurable pathways within a topological photonic metacrystal. Since the <span class="hlt">wave</span> is confined within the domain wall, which is the boundary between two distinct topological insulating systems, we can freely steer the <span class="hlt">wave</span> by reconstructing the photonic structure. Other topics, such as speckle pattern evolutions and the effects of boundary conditions on the statistics of transmission eigenvalues and energy profiles are also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA627138','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA627138"><span>Observation and Modeling of <span class="hlt">Tsunami</span>-Generated Gravity <span class="hlt">Waves</span> in the Earth’s Upper Atmosphere</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2015-10-08</p> <p>Observation and modeling of <span class="hlt">tsunami</span> -generated gravity <span class="hlt">waves</span> in the earth’s upper atmosphere 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...ABSTRACT Build a compatible set of models which 1) calculate the spectrum of atmospheric GWs excited by a <span class="hlt">tsunami</span> (using ocean model data as input...for public release; distribution is unlimited. Observation and modeling of <span class="hlt">tsunami</span> -generated gravity <span class="hlt">waves</span> in the earth’s upper atmosphere Sharon</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_4 --> <div id="page_5" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH43B1849Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH43B1849Y"><span>Hydraulic experiment on <span class="hlt">tsunami</span> sand deposits relating with grain size distribution and magnitude of incident <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yamamoto, A.; Takahashi, T.; Harada, K.; Nojima, K.</p> <p>2016-12-01</p> <p>A huge earthquake occurred off the Tohoku district in Japan on March 11th, 2011. A massive <span class="hlt">tsunami</span> generated by the earthquake attacked coastal areas and caused serious damage. The <span class="hlt">tsunami</span> disaster requires to reconsider <span class="hlt">tsunami</span> measures in the Nankai Trough. Many of the measures are based on histories of large earthquakes and <span class="hlt">tsunamis</span>. Because they are low frequency disasters and their historical documents are limited, <span class="hlt">tsunami</span> sand deposits have been expected to analyze paleotsunamis. <span class="hlt">Tsunami</span> sand deposits, however, are only used to confirm the fact of <span class="hlt">tsunamis</span> and to determine the relative magnitudes. The thickness of sand layer and the grain size may be clues to estimate the <span class="hlt">tsunami</span> force. Further, it could reveal the <span class="hlt">tsunami</span> source. These results are also useful to improve the present <span class="hlt">tsunami</span> measures. The objective of this study is to investigate the formation mechanism of <span class="hlt">tsunami</span> sand deposits by hydraulic experiment. A two-dimensional water channel consisted of a <span class="hlt">wave</span> maker, a flat section and a slope section. A movable bed section with various grain sizes and distribution of sand was set at the end of flat section. Bore <span class="hlt">waves</span> of several heights transported the sand to the slope section by run-up. Water surface elevation and velocity were measured at several points. <span class="hlt">Tsunami</span> sand deposit distribution was also measured along the slope section. The experimental result showed that the amount of <span class="hlt">tsunami</span> sand deposit was relating with the grain size distribution and the magnitude of incident <span class="hlt">waves</span>. Further, the number of incident <span class="hlt">waves</span> affected the profile of <span class="hlt">tsunami</span> sand deposits.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.1104S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.1104S"><span>Meteotsunamis, destructive <span class="hlt">tsunami</span>-like <span class="hlt">waves</span>: from observations and simulations towards a warning system (MESSI)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sepic, Jadranka; Vilibic, Ivica</p> <p>2016-04-01</p> <p>Atmospherically-generated <span class="hlt">tsunami</span>-like <span class="hlt">waves</span>, also known as meteotsunamis, pose a severe threat for exposed coastlines. Although not as destructive as ordinary <span class="hlt">tsunamis</span>, several meters high meteotsunami <span class="hlt">waves</span> can bring destruction, cause loss of human lives and raise panic. For that reason, MESSI, an integrative meteotsunami research & warning project, has been developed and will be presented herein. The project has a threefold base: (1) research of atmosphere-ocean interaction with focus on (i) source processes in the atmosphere, (ii) energy transfer to the ocean and (iii) along-<span class="hlt">propagation</span> growth of meteotsunami <span class="hlt">waves</span>; (2) estimation of meteotsunami occurrence rates in past, present and future climate, and mapping of meteotsunami hazard; (3) construction of a meteotsunami warning system prototype, with the latter being the main objective of the project. Due to a great frequency of meteotsunamis and its complex bathymetry which varies from the shallow shelf in the north towards deep pits in the south, with a number of funnel-shaped bays and harbours substantially amplifying incoming <span class="hlt">tsunami</span>-like <span class="hlt">waves</span>, the Adriatic, northernmost of the Mediterranean seas, has been chosen as an ideal area for realization of the MESSI project and implementation of the warning system. This warning system will however be designed to allow for a wider applicability and easy-to-accomplish transfer to other endangered locations. The architecture of the warning system will integrate several components: (1) real-time measurements of key oceanographic and atmospheric parameters, (2) coupled atmospheric-ocean models run in real time (warning) mode, and (3) semi-automatic procedures and protocols for warning of civil protection, local authorities and public. The effectiveness of the warning system will be tested over the historic events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7622O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7622O"><span>Sequencing of <span class="hlt">tsunami</span> <span class="hlt">waves</span>: Why the first <span class="hlt">wave</span> is not always the largest</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Okal, Emile; Synolakis, Costas</p> <p>2015-04-01</p> <p>In many instances, the largest <span class="hlt">wave</span> to hit a coastline during a <span class="hlt">tsunami</span> is not the first one. Classical examples include the arrivals of the 1960 Chilean <span class="hlt">tsunami</span> in Hilo, Hawaii, and of the 1964 Alaskan <span class="hlt">tsunami</span> in Crescent City, California, where most casualties took place during later arrivals. This situation can be socially treacherous, since residents and civil defense authorities are led to believe that the worst is over after a first, relatively mild arrival, and to give an early "all clear" before the true largest <span class="hlt">wave</span>, as was the case in Papeete, Tahiti during the 2011 Tohoku <span class="hlt">tsunami</span>. We research this problem by using a number of simple models for which analytical solutions are available, as well as more realistic simulations of the large earthquake <span class="hlt">tsunamis</span> of the past decade, and compare their results to a catalog of waveforms obtained at DART buoys spread over the Pacific Basin. Preliminary results indicate a transition from a regime of Maximum First <span class="hlt">Wave</span> to one of Delayed Maximum when distance is increased, azimuth to receiver is moved away from the normal to fault strike, and/or source size is reduced.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5627378','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5627378"><span>Uncertainties in the 2004 Sumatra–Andaman source through nonlinear stochastic inversion of <span class="hlt">tsunami</span> <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Venugopal, M.; Roy, D.; Rajendran, K.; Guillas, S.; Dias, F.</p> <p>2017-01-01</p> <p>Numerical inversions for earthquake source parameters from <span class="hlt">tsunami</span> <span class="hlt">wave</span> data usually incorporate subjective elements to stabilize the search. In addition, noisy and possibly insufficient data result in instability and non-uniqueness in most deterministic inversions, which are barely acknowledged. Here, we employ the satellite altimetry data for the 2004 Sumatra–Andaman <span class="hlt">tsunami</span> event to invert the source parameters. We also include kinematic parameters that improve the description of <span class="hlt">tsunami</span> generation and <span class="hlt">propagation</span>, especially near the source. Using a finite fault model that represents the extent of rupture and the geometry of the trench, we perform a new type of nonlinear joint inversion of the slips, rupture velocities and rise times with minimal a priori constraints. Despite persistently good waveform fits, large uncertainties in the joint parameter distribution constitute a remarkable feature of the inversion. These uncertainties suggest that objective inversion strategies should incorporate more sophisticated physical models of seabed deformation in order to significantly improve the performance of early warning systems. PMID:28989311</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH41A1748M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH41A1748M"><span>Advancing our understanding of the onshore <span class="hlt">propagation</span> of <span class="hlt">tsunami</span> bores over rough surfaces through numerical modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marras, S.; Suckale, J.; Eguzkitza, B.; Houzeaux, G.; Vázquez, M.; Lesage, A. C.</p> <p>2016-12-01</p> <p>The <span class="hlt">propagation</span> of <span class="hlt">tsunamis</span> in the open ocean has been studied in detail with many excellent numerical approaches available to researchers. Our understanding of the processes that govern the onshore <span class="hlt">propagation</span> of <span class="hlt">tsunamis</span> is less advanced. Yet, the reach of <span class="hlt">tsunamis</span> on land is an important predictor of the damage associated with a given event, highlighting the need to investigate the factors that govern <span class="hlt">tsunami</span> <span class="hlt">propagation</span> onshore. In this study, we specifically focus on understanding the effect of bottom roughness at a variety of scales. The term roughness is to be understood broadly, as it represents scales ranging from small features like rocks, to vegetation, up to the size of larger structures and topography. In this poster, we link applied mathematics, computational fluid dynamics, and <span class="hlt">tsunami</span> physics to analyze the small scales features of coastal hydrodynamics and the effect of roughness on the motion of <span class="hlt">tsunamis</span> as they run up a sloping beach and <span class="hlt">propagate</span> inland. We solve the three-dimensional Navier-Stokes equations of incompressible flows with free surface, which is tracked by a level set function in combination with an accurate re-distancing scheme. We discretize the equations via linear finite elements for space approximation and fully implicit time integration. Stabilization is achieved via the variational multiscale method whereas the subgrid scales for our large eddy simulations are modeled using a dynamically adaptive Smagorinsky eddy viscosity. As the geometrical characteristics of roughness in this study vary greatly across different scales, we implement a scale-dependent representation of the roughness elements. We model the smallest sub-grid scale roughness features by the use of a properly defined law of the wall. Furthermore, we utilize a Manning formula to compute the shear stress at the boundary. As the geometrical scales become larger, we resolve the geometry explicitly and compute the effective volume drag introduced by large scale</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23510921','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23510921"><span>Longitudinal nonlinear <span class="hlt">wave</span> <span class="hlt">propagation</span> through soft tissue.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Valdez, M; Balachandran, B</p> <p>2013-04-01</p> <p>In this paper, <span class="hlt">wave</span> <span class="hlt">propagation</span> through soft tissue is investigated. A primary aim of this investigation is to gain a fundamental understanding of the influence of soft tissue nonlinear material properties on the <span class="hlt">propagation</span> characteristics of stress <span class="hlt">waves</span> generated by transient loadings. Here, for computational modeling purposes, the soft tissue is modeled as a nonlinear visco-hyperelastic material, the geometry is assumed to be one-dimensional rod geometry, and uniaxial <span class="hlt">propagation</span> of longitudinal <span class="hlt">waves</span> is considered. By using the linearized model, a basic understanding of the characteristics of <span class="hlt">wave</span> <span class="hlt">propagation</span> is developed through the dispersion relation and in terms of the <span class="hlt">propagation</span> speed and attenuation. In addition, it is illustrated as to how the linear system can be used to predict brain tissue material parameters through the use of available experimental ultrasonic attenuation curves. Furthermore, frequency thresholds for <span class="hlt">wave</span> <span class="hlt">propagation</span> along internal structures, such as axons in the white matter of the brain, are obtained through the linear analysis. With the nonlinear material model, the authors analyze cases in which one of the ends of the rods is fixed and the other end is subjected to a loading. Two variants of the nonlinear model are analyzed and the associated predictions are compared with the predictions of the corresponding linear model. The numerical results illustrate that one of the imprints of the nonlinearity on the <span class="hlt">wave</span> <span class="hlt">propagation</span> phenomenon is the steepening of the <span class="hlt">wave</span> front, leading to jump-like variations in the stress <span class="hlt">wave</span> profiles. This phenomenon is a consequence of the dependence of the local <span class="hlt">wave</span> speed on the local deformation of the material. As per the predictions of the nonlinear material model, compressive <span class="hlt">waves</span> in the structure travel faster than tensile <span class="hlt">waves</span>. Furthermore, it is found that <span class="hlt">wave</span> pulses with large amplitudes and small elapsed times are attenuated over shorter spans. This feature is due to the elevated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20481860','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20481860"><span>Inward <span class="hlt">propagating</span> chemical <span class="hlt">waves</span> in Taylor vortices.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Thompson, Barnaby W; Novak, Jan; Wilson, Mark C T; Britton, Melanie M; Taylor, Annette F</p> <p>2010-04-01</p> <p>Advection-reaction-diffusion (ARD) <span class="hlt">waves</span> in the Belousov-Zhabotinsky reaction in steady Taylor-Couette vortices have been visualized using magnetic-resonance imaging and simulated using an adapted Oregonator model. We show how <span class="hlt">propagating</span> <span class="hlt">wave</span> behavior depends on the ratio of advective, chemical and diffusive time scales. In simulations, inward <span class="hlt">propagating</span> spiral flamelets are observed at high Damköhler number (Da). At low Da, the reaction distributes itself over several vortices and then <span class="hlt">propagates</span> inwards as contracting ring pulses--also observed experimentally.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PApGe.175.1405C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PApGe.175.1405C"><span>A Collaborative Effort Between Caribbean States for <span class="hlt">Tsunami</span> Numerical Modeling: Case Study Caribe<span class="hlt">Wave</span>15</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chacón-Barrantes, Silvia; López-Venegas, Alberto; Sánchez-Escobar, Rónald; Luque-Vergara, Néstor</p> <p>2018-04-01</p> <p>Historical records have shown that <span class="hlt">tsunami</span> have affected the Caribbean region in the past. However infrequent, recent studies have demonstrated that they pose a latent hazard for countries within this basin. The Hazard Assessment Working Group of the ICG/CARIBE-EWS (Intergovernmental Coordination Group of the Early Warning System for <span class="hlt">Tsunamis</span> and Other Coastal Threats for the Caribbean Sea and Adjacent Regions) of IOC/UNESCO has a modeling subgroup, which seeks to develop a modeling platform to assess the effects of possible <span class="hlt">tsunami</span> sources within the basin. The Caribe<span class="hlt">Wave</span> <span class="hlt">tsunami</span> exercise is carried out annually in the Caribbean region to increase awareness and test <span class="hlt">tsunami</span> preparedness of countries within the basin. In this study we present results of <span class="hlt">tsunami</span> inundation using the Caribe<span class="hlt">Wave</span>15 exercise scenario for four selected locations within the Caribbean basin (Colombia, Costa Rica, Panamá and Puerto Rico), performed by <span class="hlt">tsunami</span> modeling researchers from those selected countries. The purpose of this study was to provide the states with additional results for the exercise. The results obtained here were compared to co-seismic deformation and <span class="hlt">tsunami</span> heights within the basin (energy plots) provided for the exercise to assess the performance of the decision support tools distributed by PTWC (Pacific <span class="hlt">Tsunami</span> Warning Center), the <span class="hlt">tsunami</span> service provider for the Caribbean basin. However, comparison of coastal <span class="hlt">tsunami</span> heights was not possible, due to inconsistencies between the provided fault parameters and the modeling results within the provided exercise products. Still, the modeling performed here allowed to analyze <span class="hlt">tsunami</span> characteristics at the mentioned states from sources within the North Panamá Deformed Belt. The occurrence of a <span class="hlt">tsunami</span> in the Caribbean may affect several countries because a great variety of them share coastal zones in this basin. Therefore, collaborative efforts similar to the one presented in this study, particularly between neighboring</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PApGe.tmp..406C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PApGe.tmp..406C"><span>A Collaborative Effort Between Caribbean States for <span class="hlt">Tsunami</span> Numerical Modeling: Case Study Caribe<span class="hlt">Wave</span>15</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chacón-Barrantes, Silvia; López-Venegas, Alberto; Sánchez-Escobar, Rónald; Luque-Vergara, Néstor</p> <p>2017-10-01</p> <p>Historical records have shown that <span class="hlt">tsunami</span> have affected the Caribbean region in the past. However infrequent, recent studies have demonstrated that they pose a latent hazard for countries within this basin. The Hazard Assessment Working Group of the ICG/CARIBE-EWS (Intergovernmental Coordination Group of the Early Warning System for <span class="hlt">Tsunamis</span> and Other Coastal Threats for the Caribbean Sea and Adjacent Regions) of IOC/UNESCO has a modeling subgroup, which seeks to develop a modeling platform to assess the effects of possible <span class="hlt">tsunami</span> sources within the basin. The Caribe<span class="hlt">Wave</span> <span class="hlt">tsunami</span> exercise is carried out annually in the Caribbean region to increase awareness and test <span class="hlt">tsunami</span> preparedness of countries within the basin. In this study we present results of <span class="hlt">tsunami</span> inundation using the Caribe<span class="hlt">Wave</span>15 exercise scenario for four selected locations within the Caribbean basin (Colombia, Costa Rica, Panamá and Puerto Rico), performed by <span class="hlt">tsunami</span> modeling researchers from those selected countries. The purpose of this study was to provide the states with additional results for the exercise. The results obtained here were compared to co-seismic deformation and <span class="hlt">tsunami</span> heights within the basin (energy plots) provided for the exercise to assess the performance of the decision support tools distributed by PTWC (Pacific <span class="hlt">Tsunami</span> Warning Center), the <span class="hlt">tsunami</span> service provider for the Caribbean basin. However, comparison of coastal <span class="hlt">tsunami</span> heights was not possible, due to inconsistencies between the provided fault parameters and the modeling results within the provided exercise products. Still, the modeling performed here allowed to analyze <span class="hlt">tsunami</span> characteristics at the mentioned states from sources within the North Panamá Deformed Belt. The occurrence of a <span class="hlt">tsunami</span> in the Caribbean may affect several countries because a great variety of them share coastal zones in this basin. Therefore, collaborative efforts similar to the one presented in this study, particularly between neighboring</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29390792','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29390792"><span>Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> in monocrystalline silicon wafers.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fromme, Paul; Pizzolato, Marco; Robyr, Jean-Luc; Masserey, Bernard</p> <p>2018-01-01</p> <p>Monocrystalline silicon wafers are widely used in the photovoltaic industry for solar panels with high conversion efficiency. Guided ultrasonic <span class="hlt">waves</span> offer the potential to efficiently detect micro-cracks in the thin wafers. Previous studies of ultrasonic <span class="hlt">wave</span> <span class="hlt">propagation</span> in silicon focused on effects of material anisotropy on bulk ultrasonic <span class="hlt">waves</span>, but the dependence of the <span class="hlt">wave</span> <span class="hlt">propagation</span> characteristics on the material anisotropy is not well understood for Lamb <span class="hlt">waves</span>. The phase slowness and beam skewing of the two fundamental Lamb <span class="hlt">wave</span> modes A 0 and S 0 were investigated. Experimental measurements using contact wedge transducer excitation and laser measurement were conducted. Good agreement was found between the theoretically calculated angular dependency of the phase slowness and measurements for different <span class="hlt">propagation</span> directions relative to the crystal orientation. Significant <span class="hlt">wave</span> skew and beam widening was observed experimentally due to the anisotropy, especially for the S 0 mode. Explicit finite element simulations were conducted to visualize and quantify the guided <span class="hlt">wave</span> beam skew. Good agreement was found for the A 0 mode, but a systematic discrepancy was observed for the S 0 mode. These effects need to be considered for the non-destructive testing of wafers using guided <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFMOS23B1315V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFMOS23B1315V"><span>Pyroclastic Flow Generated <span class="hlt">Tsunami</span> <span class="hlt">Waves</span> Detected by CALIPSO Borehole Strainmeters at Soufriere Hills, Montserrat During Massive Dome Collapse: Numerical Simulations and Observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>van Boskirk, E. J.; Voight, B.; Watts, P.; Widiwijayanti, C.; Mattioli, G. S.; Elsworth, D.; Hidayat, D.; Linde, A.; Malin, P.; Neuberg, J.; Sacks, S.; Shalev, E.; Sparks, R. J.; Young, S. R.</p> <p>2004-12-01</p> <p>The July 12-13, 2003 eruption (dome collapse plus explosions) of Soufriere Hills Volcano in Montserrat, WI, is the largest historical lava dome collapse with ˜120 million cubic meters of the dome lost. Pyroclastic flows entered the sea at 18:00 AST 12 July at the Tar River Valley (TRV) and continued until the early hours of 13 July. Low-amplitude <span class="hlt">tsunamis</span> were reported at Antigua and Guadaloupe soon after the dome collapse. At the time of eruption, four CALIPSO borehole-monitoring stations were in the process of being installed, and three very-broad-band Sacks-Evertson dilatometers were operational and recorded the event at 50 sps. The strongest strain signals were recorded at the Trants site, 5 km north of the TRV entry zone, suggesting <span class="hlt">tsunami</span> <span class="hlt">waves</span> >1 m high. Debris strandlines closer to TRV recorded runup heights as much as 8 m. We test the hypothesis that the strain signal is related to <span class="hlt">tsunami</span> <span class="hlt">waves</span> generated by successive pyroclastic flows induced during the dome collapse. <span class="hlt">Tsunami</span> simulation models have been generated using GEOWAVE, which uses simple physics to recreate <span class="hlt">waves</span> generated by idealized pyroclastic flows entering the sea at TRV. Each simulation run contains surface <span class="hlt">wave</span> amplitude gauges located in key positions to the three borehole sites. These simulated <span class="hlt">wave</span> amplitudes and periods are compared quantitatively with the data recorded by the dilatometers and with field observations of <span class="hlt">wave</span> runup, to elucidate the dynamics of pyroclastic flow <span class="hlt">tsunami</span> genesis and its <span class="hlt">propagation</span> in shallow ocean water.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PApGe.175.1387D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PApGe.175.1387D"><span><span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Run-up on a Vertical Wall in Tidal Environment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Didenkulova, Ira; Pelinovsky, Efim</p> <p>2018-04-01</p> <p>We solve analytically a nonlinear problem of shallow water theory for the <span class="hlt">tsunami</span> <span class="hlt">wave</span> run-up on a vertical wall in tidal environment. Shown that the tide can be considered static in the process of <span class="hlt">tsunami</span> <span class="hlt">wave</span> run-up. In this approximation, it is possible to obtain the exact solution for the run-up height as a function of the incident <span class="hlt">wave</span> height. This allows us to investigate the tide influence on the run-up characteristics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25632135','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25632135"><span><span class="hlt">Propagating</span> <span class="hlt">waves</span> can explain irregular neural dynamics.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Keane, Adam; Gong, Pulin</p> <p>2015-01-28</p> <p>Cortical neurons in vivo fire quite irregularly. Previous studies about the origin of such irregular neural dynamics have given rise to two major models: a balanced excitation and inhibition model, and a model of highly synchronized synaptic inputs. To elucidate the network mechanisms underlying synchronized synaptic inputs and account for irregular neural dynamics, we investigate a spatially extended, conductance-based spiking neural network model. We show that <span class="hlt">propagating</span> <span class="hlt">wave</span> patterns with complex dynamics emerge from the network model. These <span class="hlt">waves</span> sweep past neurons, to which they provide highly synchronized synaptic inputs. On the other hand, these patterns only emerge from the network with balanced excitation and inhibition; our model therefore reconciles the two major models of irregular neural dynamics. We further demonstrate that the collective dynamics of <span class="hlt">propagating</span> <span class="hlt">wave</span> patterns provides a mechanistic explanation for a range of irregular neural dynamics, including the variability of spike timing, slow firing rate fluctuations, and correlated membrane potential fluctuations. In addition, in our model, the distributions of synaptic conductance and membrane potential are non-Gaussian, consistent with recent experimental data obtained using whole-cell recordings. Our work therefore relates the <span class="hlt">propagating</span> <span class="hlt">waves</span> that have been widely observed in the brain to irregular neural dynamics. These results demonstrate that neural firing activity, although appearing highly disordered at the single-neuron level, can form dynamical coherent structures, such as <span class="hlt">propagating</span> <span class="hlt">waves</span> at the population level. Copyright © 2015 the authors 0270-6474/15/351591-15$15.00/0.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730019124','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730019124"><span>ATS-5 millimeter <span class="hlt">wave</span> <span class="hlt">propagation</span> measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ippolito, L. J.</p> <p>1973-01-01</p> <p>Long term experimental measurements to determine the <span class="hlt">propagation</span> characteristics of 15 and 32 GHz earth-space links and to evaluate performance characteristics of operational millimeter <span class="hlt">wave</span> systems are reported. The ATS 5 millimeter <span class="hlt">wave</span> experimental link experienced attenuation and fading characteristics as a function of rainfall rate and other meteorological parameters. A method of site selection for the lowest attenuation rainfall rate improved reception tremendously.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28203640','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28203640"><span><span class="hlt">Tsunami</span> mitigation by resonant triad interaction with acoustic-gravity <span class="hlt">waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kadri, Usama</p> <p>2017-01-01</p> <p><span class="hlt">Tsunamis</span> have been responsible for the loss of almost a half million lives, widespread long lasting destruction, profound environmental effects, and global financial crisis, within the last two decades. The main <span class="hlt">tsunami</span> properties that determine the size of impact at the shoreline are its wavelength and amplitude in the ocean. Here, we show that it is in principle possible to reduce the amplitude of a <span class="hlt">tsunami</span>, and redistribute its energy over a larger space, through forcing it to interact with resonating acoustic-gravity <span class="hlt">waves</span>. In practice, generating the appropriate acoustic-gravity modes introduces serious challenges due to the high energy required for an effective interaction. However, if the findings are extended to realistic <span class="hlt">tsunami</span> properties and geometries, we might be able to mitigate <span class="hlt">tsunamis</span> and so save lives and properties. Moreover, such a mitigation technique would allow for the harnessing of the <span class="hlt">tsunami</span>'s energy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060044038&hterms=tsunami&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dtsunami','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060044038&hterms=tsunami&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dtsunami"><span>The 26 December 2004 <span class="hlt">tsunami</span> source estimated from satellite radar altimetry and seismic <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Song, Tony Y.; Ji, Chen; Fu, L. -L.; Zlotnicki, Victor; Shum, C. K.; Yi, Yuchan; Hjorleifsdottir, Vala</p> <p>2005-01-01</p> <p>The 26 December 2004 Indian Ocean <span class="hlt">tsunami</span> was the first earthquake <span class="hlt">tsunami</span> of its magnitude to occur since the advent of both digital seismometry and satellite radar altimetry. Both have independently recorded the event from different physical aspects. The seismic data has then been used to estimate the earthquake fault parameters, and a three-dimensional ocean-general-circulation-model (OGCM) coupled with the fault information has been used to simulate the satellite-observed <span class="hlt">tsunami</span> <span class="hlt">waves</span>. Here we show that these two datasets consistently provide the <span class="hlt">tsunami</span> source using independent methodologies of seismic waveform inversion and ocean modeling. Cross-examining the two independent results confirms that the slip function is the most important condition controlling the <span class="hlt">tsunami</span> strength, while the geometry and the rupture velocity of the tectonic plane determine the spatial patterns of the <span class="hlt">tsunami</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED258035.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED258035.pdf"><span>Antenna Construction and <span class="hlt">Propagation</span> of Radio <span class="hlt">Waves</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Marine Corps Inst., Washington, DC.</p> <p></p> <p>Developed as part of the Marine Corps Institute (MCI) correspondence training program, this course on antenna construction and <span class="hlt">propagation</span> of radio <span class="hlt">waves</span> is designed to provide communicators with instructions in the selection and/or construction of the proper antenna(s) for use with current field radio equipment. Introductory materials include…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70019856','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70019856"><span><span class="hlt">Propagation</span> of seismic <span class="hlt">waves</span> in tall buildings</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Safak, E.</p> <p>1998-01-01</p> <p>A discrete-time <span class="hlt">wave</span> <span class="hlt">propagation</span> formulation of the seismic response of tall buildings is introduced. The building is modeled as a layered medium, similar to a layered soil medium, and is subjected to vertically <span class="hlt">propagating</span> seismic shear <span class="hlt">waves</span>. Soil layers and the bedrock under the foundation are incorporated in the formulation as additional layers. Seismic response is expressed in terms of the <span class="hlt">wave</span> travel times between the layers, and the <span class="hlt">wave</span> reflection and transmission coefficients at the layer interfaces. The equations account for the frequency-dependent filtering effects of the foundation and floor masses. The calculation of seismic response is reduced to a pair of simple finite-difference equations for each layer, which can be solved recursively starting from the bedrock. Compared to the commonly used vibration formulation, the <span class="hlt">wave</span> <span class="hlt">propagation</span> formulation provides several advantages, including simplified calculations, better representation of damping, ability to account for the effects of the soil layers under the foundation, and better tools for identification and damage detection from seismic records. Examples presented show the versatility of the method. ?? 1998 John Wiley & Sons, Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17718331','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17718331"><span>Elastic guided <span class="hlt">wave</span> <span class="hlt">propagation</span> in electrical cables.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mateo, Carlos; Talavera, Juan A; Muñoz, Antonio</p> <p>2007-07-01</p> <p>This article analyzes the <span class="hlt">propagation</span> modes of ultrasound <span class="hlt">waves</span> inside an electrical cable in order to assess its behavior as an acoustic transmission channel. A theoretical model for <span class="hlt">propagation</span> of elastic <span class="hlt">waves</span> in electric power cables is presented. The power cables are represented as viscoelastic-layered cylindrical structures with a copper core and a dielectric cover. The model equations then have been applied and numerically resolved for this and other known structures such as solid and hollow cylinders. The results are compared with available data from other models. Several experimental measures were carried out and were compared with results from the numerical simulations. Experimental and simulated results showed a significant difference between elastic <span class="hlt">wave</span> attenuation inside standard versus bare, low-voltage power cables.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PApGe.tmp.1331V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PApGe.tmp.1331V"><span>Performance Comparison of NAMI DANCE and FLOW-3D® Models in <span class="hlt">Tsunami</span> <span class="hlt">Propagation</span>, Inundation and Currents using NTHMP Benchmark Problems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Velioglu Sogut, Deniz; Yalciner, Ahmet Cevdet</p> <p>2018-06-01</p> <p>Field observations provide valuable data regarding nearshore <span class="hlt">tsunami</span> impact, yet only in inundation areas where <span class="hlt">tsunami</span> <span class="hlt">waves</span> have already flooded. Therefore, <span class="hlt">tsunami</span> modeling is essential to understand <span class="hlt">tsunami</span> behavior and prepare for <span class="hlt">tsunami</span> inundation. It is necessary that all numerical models used in <span class="hlt">tsunami</span> emergency planning be subject to benchmark tests for validation and verification. This study focuses on two numerical codes, NAMI DANCE and FLOW-3D®, for validation and performance comparison. NAMI DANCE is an in-house <span class="hlt">tsunami</span> numerical model developed by the Ocean Engineering Research Center of Middle East Technical University, Turkey and Laboratory of Special Research Bureau for Automation of Marine Research, Russia. FLOW-3D® is a general purpose computational fluid dynamics software, which was developed by scientists who pioneered in the design of the Volume-of-Fluid technique. The codes are validated and their performances are compared via analytical, experimental and field benchmark problems, which are documented in the ``Proceedings and Results of the 2011 National <span class="hlt">Tsunami</span> Hazard Mitigation Program (NTHMP) Model Benchmarking Workshop'' and the ``Proceedings and Results of the NTHMP 2015 <span class="hlt">Tsunami</span> Current Modeling Workshop". The variations between the numerical solutions of these two models are evaluated through statistical error analysis.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_5 --> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22230771-tsunami-acoustic-gravity-waves-water-constant-depth','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22230771-tsunami-acoustic-gravity-waves-water-constant-depth"><span><span class="hlt">Tsunami</span> and acoustic-gravity <span class="hlt">waves</span> in water of constant depth</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hendin, Gali; Stiassnie, Michael</p> <p>2013-08-15</p> <p>A study of <span class="hlt">wave</span> radiation by a rather general bottom displacement, in a compressible ocean of otherwise constant depth, is carried out within the framework of a three-dimensional linear theory. Simple analytic expressions for the flow field, at large distance from the disturbance, are derived. Realistic numerical examples indicate that the Acoustic-Gravity <span class="hlt">waves</span>, which significantly precede the <span class="hlt">Tsunami</span>, are expected to leave a measurable signature on bottom-pressure records that should be considered for early detection of <span class="hlt">Tsunami</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25786963','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25786963"><span>Nonlinear guided <span class="hlt">wave</span> <span class="hlt">propagation</span> in prestressed plates.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pau, Annamaria; Lanza di Scalea, Francesco</p> <p>2015-03-01</p> <p>The measurement of stress in a structure presents considerable interest in many fields of engineering. In this paper, the diagnostic potential of nonlinear elastic guided <span class="hlt">waves</span> in a prestressed plate is investigated. To do so, an analytical model is formulated accounting for different aspects involved in the phenomenon. The fact that the initial strains can be finite is considered using the Green Lagrange strain tensor, and initial and final configurations are not merged, as it would be assumed in the infinitesimal strain theory. Moreover, an appropriate third-order expression of the strain energy of the hyperelastic body is adopted to account for the material nonlinearities. The model obtained enables to investigate both the linearized case, which gives the variation of phase and group velocity as a function of the initial stress, and the nonlinear case, involving second-harmonic generation as a function of the initial state of stress. The analysis is limited to Rayleigh-Lamb <span class="hlt">waves</span> <span class="hlt">propagating</span> in a plate. Three cases of initial prestress are considered, including prestress in the direction of the <span class="hlt">wave</span> <span class="hlt">propagation</span>, prestress orthogonal to the direction of <span class="hlt">wave</span> <span class="hlt">propagation</span>, and plane isotropic stress.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSPO14B2759C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSPO14B2759C"><span><span class="hlt">Tsunami</span> Defense Efforts at Samcheok Port, Korea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cho, Y. S.</p> <p>2016-02-01</p> <p><span class="hlt">Tsunamis</span> mainly triggered by impulsive undersea motions are long <span class="hlt">waves</span> and can <span class="hlt">propagate</span> a long distance. Thus, they can cause huge casualties not only neighboring countries but also distant countries. Recently, several devastating <span class="hlt">tsunamis</span> have been occurred around the Pacific Ocean rim. Among them, the Great East Japan <span class="hlt">tsunami</span> occurred on March 11, 2011 is probably recorded as one of the most destructive <span class="hlt">tsunamis</span> during last several decades. The <span class="hlt">Tsunami</span> killed more than 20,000 people (including missing people) and deprived of property damage of approximately 300 billion USD. The eastern coast of the Korean Peninsula has been attacked historically by unexpected <span class="hlt">tsunami</span> events. These <span class="hlt">tsunamis</span> were generated by undersea earthquakes occurred off the west coast of Japan. For example, the Central East Sea <span class="hlt">Tsunami</span> occurred on May 26, 1983 killed 3 people and caused serious property damage at Samcheok Port located at the eastern coast of Korea. Thus, a defense plan against unexpected <span class="hlt">tsunami</span> strikes is an essential task for the port authority to protect lives of human beings and port facilities. In this study, a master plan of <span class="hlt">tsunami</span> defense is introduced at Samcheok Port. A <span class="hlt">tsunami</span> hazard map is also made by employing both <span class="hlt">propagation</span> and inundation models. Detailed defense efforts are described including the procedure of development of a <span class="hlt">tsunami</span> hazard map. Keywords: <span class="hlt">tsunami</span>, hazard map, run-up height, emergency action plan</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22220724-propagation-sound-waves-through-spatially-homogeneous-smoothly-time-dependent-medium','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22220724-propagation-sound-waves-through-spatially-homogeneous-smoothly-time-dependent-medium"><span><span class="hlt">Propagation</span> of sound <span class="hlt">waves</span> through a spatially homogeneous but smoothly time-dependent medium</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hayrapetyan, A.G., E-mail: armen@physi.uni-heidelberg.de; Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg; Grigoryan, K.K.</p> <p>2013-06-15</p> <p>The <span class="hlt">propagation</span> of sound through a spatially homogeneous but non-stationary medium is investigated within the framework of fluid dynamics. For a non-vortical fluid, especially, a generalized <span class="hlt">wave</span> equation is derived for the (scalar) potential of the fluid velocity distribution in dependence of the equilibrium mass density of the fluid and the sound <span class="hlt">wave</span> velocity. A solution of this equation for a finite transition period τ is determined in terms of the hypergeometric function for a phenomenologically realistic, sigmoidal change of the mass density and sound <span class="hlt">wave</span> velocity. Using this solution, it is shown that the energy flux of the soundmore » <span class="hlt">wave</span> is not conserved but increases always for the <span class="hlt">propagation</span> through a non-stationary medium, independent of whether the equilibrium mass density is increased or decreased. It is found, moreover, that this amplification of the transmitted <span class="hlt">wave</span> arises from an energy exchange with the medium and that its flux is equal to the (total) flux of the incident and the reflected <span class="hlt">wave</span>. An interpretation of the reflected <span class="hlt">wave</span> as a <span class="hlt">propagation</span> of sound backward in time is given in close analogy to Feynman and Stueckelberg for the <span class="hlt">propagation</span> of anti-particles. The reflection and transmission coefficients of sound <span class="hlt">propagating</span> through a non-stationary medium is analyzed in more detail for hypersonic <span class="hlt">waves</span> with transition periods τ between 15 and 200 ps as well as the transformation of infrasound <span class="hlt">waves</span> in non-stationary oceans. -- Highlights: •Analytically exact study of sound <span class="hlt">propagation</span> through a non-stationary medium. •Energy exchange between the non-stationary medium and the sound <span class="hlt">wave</span>. •Transformation of hypersonic and ultrasound frequencies in non-stationary media. •<span class="hlt">Propagation</span> of sound backward in time in close analogy to anti-particles. •Prediction of <span class="hlt">tsunamis</span> both in spatially and temporally inhomogeneous oceans.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH43A1819G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH43A1819G"><span>Multiple Solutions of Real-time <span class="hlt">Tsunami</span> Forecasting Using Short-term Inundation Forecasting for <span class="hlt">Tsunamis</span> Tool</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gica, E.</p> <p>2016-12-01</p> <p>The Short-term Inundation Forecasting for <span class="hlt">Tsunamis</span> (SIFT) tool, developed by NOAA Center for <span class="hlt">Tsunami</span> Research (NCTR) at the Pacific Marine Environmental Laboratory (PMEL), is used in forecast operations at the <span class="hlt">Tsunami</span> Warning Centers in Alaska and Hawaii. The SIFT tool relies on a pre-computed <span class="hlt">tsunami</span> <span class="hlt">propagation</span> database, real-time DART buoy data, and an inversion algorithm to define the <span class="hlt">tsunami</span> source. The <span class="hlt">tsunami</span> <span class="hlt">propagation</span> database is composed of 50×100km unit sources, simulated basin-wide for at least 24 hours. Different combinations of unit sources, DART buoys, and length of real-time DART buoy data can generate a wide range of results within the defined <span class="hlt">tsunami</span> source. For an inexperienced SIFT user, the primary challenge is to determine which solution, among multiple solutions for a single <span class="hlt">tsunami</span> event, would provide the best forecast in real time. This study investigates how the use of different <span class="hlt">tsunami</span> sources affects simulated <span class="hlt">tsunamis</span> at tide gauge locations. Using the tide gauge at Hilo, Hawaii, a total of 50 possible solutions for the 2011 Tohoku <span class="hlt">tsunami</span> are considered. Maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> amplitude and root mean square error results are used to compare tide gauge data and the simulated <span class="hlt">tsunami</span> time series. Results of this study will facilitate SIFT users' efforts to determine if the simulated tide gauge <span class="hlt">tsunami</span> time series from a specific <span class="hlt">tsunami</span> source solution would be within the range of possible solutions. This study will serve as the basis for investigating more historical <span class="hlt">tsunami</span> events and tide gauge locations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JPhCS.957a2005F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JPhCS.957a2005F"><span>Gravitational <span class="hlt">Waves</span> <span class="hlt">Propagation</span> through the Stochastic Background of Gravitational <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Frajuca, C.; Bortoli, F. S.; Nakamoto, F. Y.; Santos, G. A.</p> <p>2018-02-01</p> <p>With the recent claim that gravitational <span class="hlt">waves</span> were finally detected and with other efforts around the world for GWs detection, its is reasonable to imagine that the relic gravitational <span class="hlt">wave</span> background could be detected in some time in the future and with such information gather some hints about the origin of the universe. But, it’s also be considered that gravity has self-interaction, with such assumption it’s reasonable to expect that these gravitational <span class="hlt">wave</span> will interact with the relic or nonrelic GW background by scattering, for example. Such interaction should decrease the distance which such <span class="hlt">propagating</span> <span class="hlt">waves</span> could be detected The <span class="hlt">propagation</span> of gravitational <span class="hlt">waves</span> (GWs) is analyzed in an asymptotically de Sitter space by the perturbation expansion around Minkowski space using a scalar component. Using the case of de Sitter inflationary phase scenario, the perturbation <span class="hlt">propagates</span> through a FRW background. The GW, using the actual value for the Hubble scale (Ho), has a damping factor with a very small valor for the size of the observational universe; the stochastic relic GW background is given by a dimensionless function of the frequency. In this work we analyze this same damping including the gravitational <span class="hlt">wave</span> background due to astrophysical sources such background is 3 orders of magnitude bigger in some frequencies and produces a higher damping factor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD1013882','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD1013882"><span>Elastic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> Mechanisms in Underwater Acoustic Environments</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2015-09-30</p> <p>Elastic <span class="hlt">wave</span> <span class="hlt">propagation</span> mechanisms in underwater acoustic environments Scott D. Frank Marist College Department of Mathematics Poughkeepsie...conversion from elastic <span class="hlt">propagation</span> to acoustic <span class="hlt">propagation</span>, and intense interface <span class="hlt">waves</span> on underwater acoustic environments with elastic bottoms...acoustic <span class="hlt">propagation</span> will be considered as a means to predict the presence of elastic ice layers. APPROACH In a cylindrically symmetric environment</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhRvA..97c3843L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhRvA..97c3843L"><span>Electromagnetic <span class="hlt">wave</span> <span class="hlt">propagating</span> along a space curve</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lai, Meng-Yun; Wang, Yong-Long; Liang, Guo-Hua; Wang, Fan; Zong, Hong-Shi</p> <p>2018-03-01</p> <p>By using the thin-layer approach, we derive the effective equation for the electromagnetic <span class="hlt">wave</span> <span class="hlt">propagating</span> along a space curve. We find intrinsic spin-orbit, extrinsic spin-orbit, and extrinsic orbital angular-momentum and intrinsic orbital angular-momentum couplings induced by torsion, which can lead to geometric phase, spin, and orbital Hall effects. And we show the helicity inversion induced by curvature that can convert a right-handed circularly polarized electromagnetic <span class="hlt">wave</span> into a left-handed polarized one, vice versa. Finally, we demonstrate that the gauge invariance of the effective dynamics is protected by the geometrically induced gauge potential.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA229363','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA229363"><span>Millimetre <span class="hlt">Wave</span> <span class="hlt">Propagation</span> Over the Sea</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1990-10-29</p> <p>Rennes-Armees B-1110 Brussels France Belgium (Not a Distribution Centre) 12. Distribution Statement: Approved lor public release. Distribution of this...millimetre <span class="hlt">waves</span> above the sea have taken place on the French Atlantic coast near the town of Lorient (Brittany). The length of the <span class="hlt">propagation</span> path was 9.7...ORIGINAL: FRENCH TECHNICAL REPORT 29th October 1990 AC/243(Panel 3)TR/3 DEFENCE RESEARCH GROUP PANEL 3 ON PHYSICS AND ELECTRONICS Technical Report on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70160542','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70160542"><span>Non-linear resonant coupling of <span class="hlt">tsunami</span> edge <span class="hlt">waves</span> using stochastic earthquake source models</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, Eric L.</p> <p>2016-01-01</p> <p>Non-linear resonant coupling of edge <span class="hlt">waves</span> can occur with <span class="hlt">tsunamis</span> generated by large-magnitude subduction zone earthquakes. Earthquake rupture zones that straddle beneath the coastline of continental margins are particularly efficient at generating <span class="hlt">tsunami</span> edge <span class="hlt">waves</span>. Using a stochastic model for earthquake slip, it is shown that a wide range of edge-<span class="hlt">wave</span> modes and wavenumbers can be excited, depending on the variability of slip. If two modes are present that satisfy resonance conditions, then a third mode can gradually increase in amplitude over time, even if the earthquake did not originally excite that edge-<span class="hlt">wave</span> mode. These three edge <span class="hlt">waves</span> form a resonant triad that can cause unexpected variations in <span class="hlt">tsunami</span> amplitude long after the first arrival. An M ∼ 9, 1100 km-long continental subduction zone earthquake is considered as a test case. For the least-variable slip examined involving a Gaussian random variable, the dominant resonant triad includes a high-amplitude fundamental mode <span class="hlt">wave</span> with wavenumber associated with the along-strike dimension of rupture. The two other <span class="hlt">waves</span> that make up this triad include subharmonic <span class="hlt">waves</span>, one of fundamental mode and the other of mode 2 or 3. For the most variable slip examined involving a Cauchy-distributed random variable, the dominant triads involve higher wavenumbers and modes because subevents, rather than the overall rupture dimension, control the excitation of edge <span class="hlt">waves</span>. Calculation of the resonant period for energy transfer determines which cases resonant coupling may be instrumentally observed. For low-mode triads, the maximum transfer of energy occurs approximately 20–30 <span class="hlt">wave</span> periods after the first arrival and thus may be observed prior to the <span class="hlt">tsunami</span> coda being completely attenuated. Therefore, under certain circumstances the necessary ingredients for resonant coupling of <span class="hlt">tsunami</span> edge <span class="hlt">waves</span> exist, indicating that resonant triads may be observable and implicated in late, large-amplitude <span class="hlt">tsunami</span> arrivals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1369205-simulations-seismic-wave-propagation-mars','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1369205-simulations-seismic-wave-propagation-mars"><span>Simulations of Seismic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> on Mars</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Bozdağ, Ebru; Ruan, Youyi; Metthez, Nathan; ...</p> <p>2017-03-23</p> <p>In this paper, we present global and regional synthetic seismograms computed for 1D and 3D Mars models based on the spectral-element method. For global simulations, we implemented a radially-symmetric Mars model with a 110 km thick crust. For this 1D model, we successfully benchmarked the 3D seismic <span class="hlt">wave</span> <span class="hlt">propagation</span> solver SPECFEM3D_GLOBE against the 2D axisymmetric <span class="hlt">wave</span> <span class="hlt">propagation</span> solver AxiSEM at periods down to 10 s. We also present higher-resolution body-<span class="hlt">wave</span> simulations with AxiSEM down to 1 s in a model with a more complex 1D crust, revealing <span class="hlt">wave</span> <span class="hlt">propagation</span> effects that would have been difficult to interpret based on raymore » theory. For 3D global simulations based on SPECFEM3D_GLOBE, we superimposed 3D crustal thickness variations capturing the distinct crustal dichotomy between Mars’ northern and southern hemispheres, as well as topography, ellipticity, gravity, and rotation. The global simulations clearly indicate that the 3D crust speeds up body <span class="hlt">waves</span> compared to the reference 1D model, whereas it significantly changes surface waveforms and their dispersive character depending on its thickness. We also perform regional simulations with the solver SES3D based on 3D crustal models derived from surface composition, thereby addressing the effects of various distinct crustal features down to 2 s. The regional simulations confirm the strong effects of crustal variations on waveforms. Finally, we conclude that the numerical tools are ready for examining more scenarios, including various other seismic models and sources.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1369205','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1369205"><span>Simulations of Seismic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> on Mars</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bozdağ, Ebru; Ruan, Youyi; Metthez, Nathan</p> <p></p> <p>In this paper, we present global and regional synthetic seismograms computed for 1D and 3D Mars models based on the spectral-element method. For global simulations, we implemented a radially-symmetric Mars model with a 110 km thick crust. For this 1D model, we successfully benchmarked the 3D seismic <span class="hlt">wave</span> <span class="hlt">propagation</span> solver SPECFEM3D_GLOBE against the 2D axisymmetric <span class="hlt">wave</span> <span class="hlt">propagation</span> solver AxiSEM at periods down to 10 s. We also present higher-resolution body-<span class="hlt">wave</span> simulations with AxiSEM down to 1 s in a model with a more complex 1D crust, revealing <span class="hlt">wave</span> <span class="hlt">propagation</span> effects that would have been difficult to interpret based on raymore » theory. For 3D global simulations based on SPECFEM3D_GLOBE, we superimposed 3D crustal thickness variations capturing the distinct crustal dichotomy between Mars’ northern and southern hemispheres, as well as topography, ellipticity, gravity, and rotation. The global simulations clearly indicate that the 3D crust speeds up body <span class="hlt">waves</span> compared to the reference 1D model, whereas it significantly changes surface waveforms and their dispersive character depending on its thickness. We also perform regional simulations with the solver SES3D based on 3D crustal models derived from surface composition, thereby addressing the effects of various distinct crustal features down to 2 s. The regional simulations confirm the strong effects of crustal variations on waveforms. Finally, we conclude that the numerical tools are ready for examining more scenarios, including various other seismic models and sources.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SSRv..211..571B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SSRv..211..571B"><span>Simulations of Seismic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> on Mars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bozdağ, Ebru; Ruan, Youyi; Metthez, Nathan; Khan, Amir; Leng, Kuangdai; van Driel, Martin; Wieczorek, Mark; Rivoldini, Attilio; Larmat, Carène S.; Giardini, Domenico; Tromp, Jeroen; Lognonné, Philippe; Banerdt, Bruce W.</p> <p>2017-10-01</p> <p>We present global and regional synthetic seismograms computed for 1D and 3D Mars models based on the spectral-element method. For global simulations, we implemented a radially-symmetric Mars model with a 110 km thick crust (Sohl and Spohn in J. Geophys. Res., Planets 102(E1):1613-1635, 1997). For this 1D model, we successfully benchmarked the 3D seismic <span class="hlt">wave</span> <span class="hlt">propagation</span> solver SPECFEM3D_GLOBE (Komatitsch and Tromp in Geophys. J. Int. 149(2):390-412, 2002a; 150(1):303-318, 2002b) against the 2D axisymmetric <span class="hlt">wave</span> <span class="hlt">propagation</span> solver AxiSEM (Nissen-Meyer et al. in Solid Earth 5(1):425-445, 2014) at periods down to 10 s. We also present higher-resolution body-<span class="hlt">wave</span> simulations with AxiSEM down to 1 s in a model with a more complex 1D crust, revealing <span class="hlt">wave</span> <span class="hlt">propagation</span> effects that would have been difficult to interpret based on ray theory. For 3D global simulations based on SPECFEM3D_GLOBE, we superimposed 3D crustal thickness variations capturing the distinct crustal dichotomy between Mars' northern and southern hemispheres, as well as topography, ellipticity, gravity, and rotation. The global simulations clearly indicate that the 3D crust speeds up body <span class="hlt">waves</span> compared to the reference 1D model, whereas it significantly changes surface waveforms and their dispersive character depending on its thickness. We also perform regional simulations with the solver SES3D (Fichtner et al. Geophys. J. Int. 179:1703-1725, 2009) based on 3D crustal models derived from surface composition, thereby addressing the effects of various distinct crustal features down to 2 s. The regional simulations confirm the strong effects of crustal variations on waveforms. We conclude that the numerical tools are ready for examining more scenarios, including various other seismic models and sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.204..719O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.204..719O"><span>Sequencing of <span class="hlt">tsunami</span> <span class="hlt">waves</span>: why the first <span class="hlt">wave</span> is not always the largest</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Okal, Emile A.; Synolakis, Costas E.</p> <p>2016-02-01</p> <p>This paper examines the factors contributing to the `sequencing' of <span class="hlt">tsunami</span> <span class="hlt">waves</span> in the far field, that is, to the distribution of the maximum sea surface amplitude inside the dominant <span class="hlt">wave</span> packet constituting the primary arrival at a distant harbour. Based on simple models of sources for which analytical solutions are available, we show that, as range is increased, the <span class="hlt">wave</span> pattern evolves from a regime of maximum amplitude in the first oscillation to one of delayed maximum, where the largest amplitude takes place during a subsequent oscillation. In the case of the simple, instantaneous uplift of a circular disk at the surface of an ocean of constant depth, the critical distance for transition between those patterns scales as r_0^3 / h^2 where r0 is the radius of the disk and h the depth of the ocean. This behaviour is explained from simple arguments based on a model where sequencing results from frequency dispersion in the primary <span class="hlt">wave</span> packet, as the width of its spectrum around its dominant period T0 becomes dispersed in time in an amount comparable to T0, the latter being controlled by a combination of source size and ocean depth. The general concepts in this model are confirmed in the case of more realistic sources for <span class="hlt">tsunami</span> excitation by a finite-time deformation of the ocean floor, as well as in real-life simulations of <span class="hlt">tsunamis</span> excited by large subduction events, for which we find that the influence of fault width on the distribution of sequencing is more important than that of fault length. Finally, simulation of the major events of Chile (2010) and Japan (2011) at large arrays of virtual gauges in the Pacific Basin correctly predicts the majority of the sequencing patterns observed on DART buoys during these events. By providing insight into the evolution with time of <span class="hlt">wave</span> amplitudes inside primary <span class="hlt">wave</span> packets for far field <span class="hlt">tsunamis</span> generated by large earthquakes, our results stress the importance, for civil defense authorities, of issuing warning and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH34A..03S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH34A..03S"><span>SEQUENCING of <span class="hlt">TSUNAMI</span> <span class="hlt">WAVES</span>: Why the first <span class="hlt">wave</span> is not always the largest?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Synolakis, C.; Okal, E.</p> <p>2016-12-01</p> <p>We discuss what contributes to the `sequencing' of <span class="hlt">tsunami</span> <span class="hlt">waves</span> in the far field, that is, to the distribution of the maximum sea surface amplitude inside the dominant <span class="hlt">wave</span> packet constituting the primary arrival at a distant harbour. Based on simple models of sources for which analytical solutions are available, we show that, as range is increased, the <span class="hlt">wave</span> pattern evolves from a regime of maximum amplitude in the first oscillation to one of delayed maximum, where the largest amplitude takes place during a subsequent oscillation. In the case of the simple, instantaneous uplift of a circular disk at the surface of an ocean of constant depth, the critical distance for transition between those patterns scales as r 30 /h2 where r0 is the radius of the disk and h the depth of the ocean. This behaviour is explained from simple arguments based on a model where sequencing results from frequency dispersion in the primary <span class="hlt">wave</span> packet, as the width of its spectrum around its dominant period T0 becomes dispersed in time in an amount comparable to T0 , the latter being controlled by a combination of source size and ocean depth. The general concepts in this model are confirmed in the case of more realistic sources for <span class="hlt">tsunami</span> excitation by a finite-time deformation of the ocean floor, as well as in real-life simulations of <span class="hlt">tsunamis</span> excited by large subduction events, for which we find that the influence of fault width on the distribution of sequencing is more important than that of fault length. Finally, simulation of the major events of Chile (2010) and Japan (2011) at large arrays of virtual gauges in the Pacific Basin correctly predicts the majority of the sequencing patterns observed on DART buoys during these events. By providing insight into the evolution with time of <span class="hlt">wave</span> amplitudes inside primary <span class="hlt">wave</span> packets for far field <span class="hlt">tsunamis</span> generated by large earthquakes, our results stress the importance, for civil defense authorities, of issuing warning and evacuation orders</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.T13D3041E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.T13D3041E"><span>Seismic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> on the Tablet Computer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Emoto, K.</p> <p>2015-12-01</p> <p>Tablet computers widely used in recent years. The performance of the tablet computer is improving year by year. Some of them have performance comparable to the personal computer of a few years ago with respect to the calculation speed and the memory size. The convenience and the intuitive operation are the advantage of the tablet computer compared to the desktop PC. I developed the iPad application of the numerical simulation of the seismic <span class="hlt">wave</span> <span class="hlt">propagation</span>. The numerical simulation is based on the 2D finite difference method with the staggered-grid scheme. The number of the grid points is 512 x 384 = 196,608. The grid space is 200m in both horizontal and vertical directions. That is the calculation area is 102km x 77km. The time step is 0.01s. In order to reduce the user waiting time, the image of the <span class="hlt">wave</span> field is drawn simultaneously with the calculation rather than playing the movie after the whole calculation. P and S <span class="hlt">wave</span> energies are plotted on the screen every 20 steps (0.2s). There is the trade-off between the smooth simulation and the resolution of the <span class="hlt">wave</span> field image. In the current setting, it takes about 30s to calculate the 10s <span class="hlt">wave</span> <span class="hlt">propagation</span> (50 times image updates). The seismogram at the receiver is displayed below of the <span class="hlt">wave</span> field updated in real time. The default medium structure consists of 3 layers. The layer boundary is defined by 10 movable points with linear interpolation. Users can intuitively change to the arbitrary boundary shape by moving the point. Also users can easily change the source and the receiver positions. The favorite structure can be saved and loaded. For the advance simulation, users can introduce the random velocity fluctuation whose spectrum can be changed to the arbitrary shape. By using this application, everyone can simulate the seismic <span class="hlt">wave</span> <span class="hlt">propagation</span> without the special knowledge of the elastic <span class="hlt">wave</span> equation. So far, the Japanese version of the application is released on the App Store. Now I am preparing the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018SPIE10602E..0BA','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018SPIE10602E..0BA"><span>Bulk-<span class="hlt">wave</span> ultrasonic <span class="hlt">propagation</span> imagers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abbas, Syed Haider; Lee, Jung-Ryul</p> <p>2018-03-01</p> <p>Laser-based ultrasound systems are described that utilize the ultrasonic bulk-<span class="hlt">wave</span> sensing to detect the damages and flaws in the aerospace structures. These systems apply pulse-echo or through transmission methods to detect longitudinal through-the-thickness bulk-<span class="hlt">waves</span>. These thermoelastic <span class="hlt">waves</span> are generated using Q-switched laser and non-contact sensing is performed using a laser Doppler vibrometer (LDV). Laser-based raster scanning is performed by either twoaxis translation stage for linear-scanning or galvanometer-based laser mirror scanner for angular-scanning. In all ultrasonic <span class="hlt">propagation</span> imagers, the ultrasonic data is captured and processed in real-time and the ultrasonic <span class="hlt">propagation</span> can be visualized during scanning. The scanning speed can go up to 1.8 kHz for two-axis linear translation stage based B-UPIs and 10 kHz for galvanometer-based laser mirror scanners. In contrast with the other available ultrasound systems, these systems have the advantage of high-speed, non-contact, real-time, and non-destructive inspection. In this paper, the description of all bulk-<span class="hlt">wave</span> ultrasonic imagers (B-UPIs) are presented and their advantages are discussed. Experiments are performed with these system on various structures to proof the integrity of their results. The C-scan results produced from non-dispersive, through-the-thickness, bulk-<span class="hlt">wave</span> detection show good agreement in detection of structural variances and damage location in all inspected structures. These results show that bulk-<span class="hlt">wave</span> UPIs can be used for in-situ NDE of engineering structures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JSV...393..133S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JSV...393..133S"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in axially moving periodic strings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sorokin, Vladislav S.; Thomsen, Jon Juel</p> <p>2017-04-01</p> <p>The paper deals with analytically studying transverse <span class="hlt">waves</span> <span class="hlt">propagation</span> in an axially moving string with periodically modulated cross section. The structure effectively models various relevant technological systems, e.g. belts, thread lines, band saws, etc., and, in particular, roller chain drives for diesel engines by capturing both their spatial periodicity and axial motion. The Method of Varying Amplitudes is employed in the analysis. It is shown that the compound <span class="hlt">wave</span> traveling in the axially moving periodic string comprises many components with different frequencies and wavenumbers. This is in contrast to non-moving periodic structures, for which all components of the corresponding compound <span class="hlt">wave</span> feature the same frequency. Due to this "multi-frequency" character of the <span class="hlt">wave</span> motion, the conventional notion of frequency band-gaps appears to be not applicable for the moving periodic strings. Thus, for such structures, by frequency band-gaps it is proposed to understand frequency ranges in which the primary component of the compound <span class="hlt">wave</span> attenuates. Such frequency band-gaps can be present for a moving periodic string, but only if its axial velocity is lower than the transverse <span class="hlt">wave</span> speed, and, the higher the axial velocity, the narrower the frequency band-gaps. The revealed effects could be of potential importance for applications, e.g. they indicate that due to spatial inhomogeneity, oscillations of axially moving periodic chains always involve a multitude of frequencies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/877842','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/877842"><span>Modeling <span class="hlt">Propagation</span> of Shock <span class="hlt">Waves</span> in Metals</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Howard, W M; Molitoris, J D</p> <p>2005-08-19</p> <p>We present modeling results for the <span class="hlt">propagation</span> of strong shock <span class="hlt">waves</span> in metals. In particular, we use an arbitrary Lagrange Eulerian (ALE3D) code to model the <span class="hlt">propagation</span> of strong pressure <span class="hlt">waves</span> (P {approx} 300 to 400 kbars) generated with high explosives in contact with aluminum cylinders. The aluminum cylinders are assumed to be both flat-topped and have large-amplitude curved surfaces. We use 3D Lagrange mechanics. For the aluminum we use a rate-independent Steinberg-Guinan model, where the yield strength and shear modulus depend on pressure, density and temperature. The calculation of the melt temperature is based on the Lindermann law. Atmore » melt the yield strength and shear modulus is set to zero. The pressure is represented as a seven-term polynomial as a function of density. For the HMX-based high explosive, we use a JWL, with a program burn model that give the correct detonation velocity and C-J pressure (P {approx} 390 kbars). For the case of the large-amplitude curved surface, we discuss the evolving shock structure in terms of the early shock <span class="hlt">propagation</span> experiments by Sakharov.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AIPC..845..319H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AIPC..845..319H"><span>Modeling <span class="hlt">Propagation</span> of Shock <span class="hlt">Waves</span> in Metals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Howard, W. M.; Molitoris, J. D.</p> <p>2006-07-01</p> <p>We present modeling results for the <span class="hlt">propagation</span> of strong shock <span class="hlt">waves</span> in metals. In particular, we use an arbitrary Lagrange Eulerian (ALE3D) code to model the <span class="hlt">propagation</span> of strong pressure <span class="hlt">waves</span> (P ˜ 300 to 400 kbars) generated with high explosives in contact with aluminum cylinders. The aluminum cylinders are assumed to be both flat-topped and have large-amplitude curved surfaces. We use 3D Lagrange mechanics. For the aluminum we use a rate-independent Steinberg-Guinan model, where the yield strength and shear modulus depend on pressure, density and temperature. The calculation of the melt temperature is based on the Lindermann law. At melt the yield strength and shear modulus is set to zero. The pressure is represented as a seven-term polynomial as a function of density. For the HMX-based high explosive, we use a JWL, with a program burn model that give the correct detonation velocity and C-J pressure (P ˜ 390 kbars). For the case of the large-amplitude curved surface, we discuss the evolving shock structure in terms of the early shock <span class="hlt">propagation</span> experiments by Sakharov.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27906274','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27906274"><span>General <span class="hlt">wave</span> optics <span class="hlt">propagation</span> scaling law.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Shakir, Sami A; Dolash, Thomas M; Spencer, Mark; Berdine, Richard; Cargill, Daniel S; Carreras, Richard</p> <p>2016-12-01</p> <p>A general far-field <span class="hlt">wave</span> <span class="hlt">propagation</span> scaling law is developed. The formulation is simple but predicts diffraction peak irradiance accurately in the far field, regardless of the near-field beam type or geometry, including laser arrays. We also introduce the concept of the equivalent uniform circular beam that generates a far-field peak irradiance and power-in-the-bucket that are the same as an arbitrary laser source. Applications to clipped Gaussian beams with an obscuration, both as a single beam and as an array of beams, are shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016DPS....4820902T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016DPS....4820902T"><span>Seismic <span class="hlt">wave</span> <span class="hlt">propagation</span> in granular media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tancredi, Gonzalo; López, Francisco; Gallot, Thomas; Ginares, Alejandro; Ortega, Henry; Sanchís, Johnny; Agriela, Adrián; Weatherley, Dion</p> <p>2016-10-01</p> <p>Asteroids and small bodies of the Solar System are thought to be agglomerates of irregular boulders, therefore cataloged as granular media. It is a consensus that many asteroids might be considered as rubble or gravel piles.Impacts on their surface could produce seismic <span class="hlt">waves</span> which <span class="hlt">propagate</span> in the interior of these bodies, thus causing modifications in the internal distribution of rocks and ejections of particles and dust, resulting in a cometary-type comma.We present experimental and numerical results on the study of <span class="hlt">propagation</span> of impact-induced seismic <span class="hlt">waves</span> in granular media, with special focus on behavior changes by increasing compression.For the experiment, we use an acrylic box filled with granular materials such as sand, gravel and glass spheres. Pressure inside the box is controlled by a movable side wall and measured with sensors. Impacts are created on the upper face of the box through a hole, ranging from free-falling spheres to gunshots. We put high-speed cameras outside the box to record the impact as well as piezoelectic sensors and accelerometers placed at several depths in the granular material to detect the seismic <span class="hlt">wave</span>.Numerical simulations are performed with ESyS-Particle, a software that implements the Discrete Element Method. The experimental setting is reproduced in the numerical simulations using both individual spherical particles and agglomerates of spherical particles shaped as irregular boulders, according to rock models obtained with a 3D scanner. The numerical experiments also reproduces the force loading on one of the wall to vary the pressure inside the box.We are interested in the velocity, attenuation and energy transmission of the <span class="hlt">waves</span>. These quantities are measured in the experiments and in the simulations. We study the dependance of these three parameters with characteristics like: impact speed, properties of the target material and the pressure in the media.These results are relevant to understand the outcomes of impacts in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.2669B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.2669B"><span><span class="hlt">Propagation</span> of gravity <span class="hlt">waves</span> across the tropopause</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bense, Vera; Spichtinger, Peter</p> <p>2015-04-01</p> <p>The tropopause region is characterised by strong gradients in various atmospheric quantities that exhibit different properties in the troposphere compared to the stratosphere. The temperature lapse rate typically changes from negative to near-zero values resulting in a strong increase in stability. Accordingly, the buoyancy frequency often undergoes a jump at the tropopause. Analysis of radiosounding data also shows the existence of a strong inversion layer (tropopause inversion layer, TIL) characterised by a strong maximum in buoyancy frequency just above the tropopause, see e.g. Birner et al. (2002). Additionally, the magnitude of the vertical wind shear of the horizontal wind maximizes at the tropopause and the region also exhibits characteristical gradients of trace gases. Vertically <span class="hlt">propagating</span> gravity <span class="hlt">waves</span> can be excited in the troposphere by several mechanisms, e.g. by flow over topography (e.g. Durran, 1990), by jets and fronts (for a recent review: Plougonven and Zhang, 1990) or by convection (e.g. Clark et al., 1986). When these <span class="hlt">waves</span> enter the tropopause region, their properties can be changed drastically by the changing stratification and strong wind shear. Within this work, the EULAG (Eulerian/semi-Lagrangian fluid solver, see e.g. Smolarkiewicz and Margolin, 1997) model is used to investigate the impact of the tropopause on vertically <span class="hlt">propagating</span> gravity <span class="hlt">waves</span> excited by flows over topography. The choice of topography (sine-shaped mountains, bell-shaped mountain) along with horizontal wind speed and tropospheric value of buoyancy frequency determine the spectrum of <span class="hlt">waves</span> (horizontal and vertical wavelengths) that is excited in the tropsphere. In order to analyse how these spectra change for several topographies when a tropopause is present, we investigate different idealized cases in a two-dimensional domain. By varying the vertical profiles of buoyancy frequency (step-wise vs. continuos change, including TIL) and wind shear, the tropopause</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010RvGeo..48.4006W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010RvGeo..48.4006W"><span>Impact of a Cosmic Body into Earth's Ocean and the Generation of Large <span class="hlt">Tsunami</span> <span class="hlt">Waves</span>: Insight from Numerical Modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wünnemann, K.; Collins, G. S.; Weiss, R.</p> <p>2010-12-01</p> <p>The strike of a cosmic body into a marine environment differs in several respects from impact on land. Oceans cover approximately 70% of the Earth's surface, implying not only that oceanic impact is a very likely scenario for future impacts but also that most impacts in Earth's history must have happened in marine environments. Therefore, the study of oceanic impact is imperative in two respects: (1) to quantify the hazard posed by future oceanic impacts, including the potential threat of large impact-generated <span class="hlt">tsunami</span>-like <span class="hlt">waves</span>, and (2) to reconstruct Earth's impact record by accounting for the large number of potentially undiscovered crater structures in the ocean crust. Reconstruction of the impact record is of crucial importance both for assessing the frequency of collision events in the past and for better predicting the probability of future impact. We summarize the advances in the study of oceanic impact over the last decades and focus in particular on how numerical models have improved our understanding of cratering in the oceanic environment and the generation of <span class="hlt">waves</span> by impact. We focus on insight gleaned from numerical modeling studies into the deceleration of the projectile by the water, cratering of the ocean floor, the late stage modification of the crater due to gravitational collapse, and water resurge. Furthermore, we discuss the generation and <span class="hlt">propagation</span> of large <span class="hlt">tsunami</span>-like <span class="hlt">waves</span> as a result of a strike of a cosmic body in marine environments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.7776B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.7776B"><span>Advanced Simulation of Coupled Earthquake and <span class="hlt">Tsunami</span> Events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Behrens, Joern</p> <p>2013-04-01</p> <p><span class="hlt">Tsunami</span>-Earthquakes represent natural catastrophes threatening lives and well-being of societies in a solitary and unexpected extreme event as tragically demonstrated in Sumatra (2004), Samoa (2009), Chile (2010), or Japan (2011). Both phenomena are consequences of the complex system of interactions of tectonic stress, fracture mechanics, rock friction, rupture dynamics, fault geometry, ocean bathymetry, and coastline geometry. The ASCETE project forms an interdisciplinary research consortium that couples the most advanced simulation technologies for earthquake rupture dynamics and <span class="hlt">tsunami</span> <span class="hlt">propagation</span> to understand the fundamental conditions of <span class="hlt">tsunami</span> generation. We report on the latest research results in physics-based dynamic rupture and <span class="hlt">tsunami</span> <span class="hlt">wave</span> <span class="hlt">propagation</span> simulation, using unstructured and adaptive meshes with continuous and discontinuous Galerkin discretization approaches. Coupling both simulation tools - the physics-based dynamic rupture simulation and the hydrodynamic <span class="hlt">tsunami</span> <span class="hlt">wave</span> <span class="hlt">propagation</span> - will give us the possibility to conduct highly realistic studies of the interaction of rupture dynamics and <span class="hlt">tsunami</span> impact characteristics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PApGe.170.1621P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PApGe.170.1621P"><span>A Probabilistic <span class="hlt">Tsunami</span> Hazard Study of the Auckland Region, Part I: <span class="hlt">Propagation</span> Modelling and <span class="hlt">Tsunami</span> Hazard Assessment at the Shoreline</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Power, William; Wang, Xiaoming; Lane, Emily; Gillibrand, Philip</p> <p>2013-09-01</p> <p>Regional source <span class="hlt">tsunamis</span> represent a potentially devastating threat to coastal communities in New Zealand, yet are infrequent events for which little historical information is available. It is therefore essential to develop robust methods for quantitatively estimating the hazards posed, so that effective mitigation measures can be implemented. We develop a probabilistic model for the <span class="hlt">tsunami</span> hazard posed to the Auckland region of New Zealand from the Kermadec Trench and the southern New Hebrides Trench subduction zones. An innovative feature of our model is the systematic analysis of uncertainty regarding the magnitude-frequency distribution of earthquakes in the source regions. The methodology is first used to estimate the <span class="hlt">tsunami</span> hazard at the coastline, and then used to produce a set of scenarios that can be applied to produce probabilistic maps of <span class="hlt">tsunami</span> inundation for the study region; the production of these maps is described in part II. We find that the 2,500 year return period regional source <span class="hlt">tsunami</span> hazard for the densely populated east coast of Auckland is dominated by events originating in the Kermadec Trench, while the equivalent hazard to the sparsely populated west coast is approximately equally due to events on the Kermadec Trench and the southern New Hebrides Trench.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Nonli..28.4389F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Nonli..28.4389F"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in predator-prey systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fu, Sheng-Chen; Tsai, Je-Chiang</p> <p>2015-12-01</p> <p>In this paper, we study a class of predator-prey systems of reaction-diffusion type. Specifically, we are interested in the dynamical behaviour for the solution with the initial distribution where the prey species is at the level of the carrying capacity, and the density of the predator species has compact support, or exponentially small tails near x=+/- ∞ . Numerical evidence suggests that this will lead to the formation of a pair of diverging <span class="hlt">waves</span> <span class="hlt">propagating</span> outwards from the initial zone. Motivated by this phenomenon, we establish the existence of a family of travelling <span class="hlt">waves</span> with the minimum speed. Unlike the previous studies, we do not use the shooting argument to show this. Instead, we apply an iteration process based on Berestycki et al 2005 (Math Comput. Modelling 50 1385-93) to construct a set of super/sub-solutions. Since the underlying system does not enjoy the comparison principle, such a set of super/sub-solutions is not based on travelling <span class="hlt">waves</span>, and in fact the super/sub-solutions depend on each other. With the aid of the set of super/sub-solutions, we can construct the solution of the truncated problem on the finite interval, which, via the limiting argument, can in turn generate the <span class="hlt">wave</span> solution. There are several advantages to this approach. First, it can remove the technical assumptions on the diffusivities of the species in the existing literature. Second, this approach is of PDE type, and hence it can shed some light on the spreading phenomenon indicated by numerical simulation. In fact, we can compute the spreading speed of the predator species for a class of biologically acceptable initial distributions. Third, this approach might be applied to the study of <span class="hlt">waves</span> in non-cooperative systems (i.e. a system without a comparison principle).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14..105D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14..105D"><span>Nonlinear <span class="hlt">wave</span> runup in long bays and firths: Samoa 2009 and Tohoku 2011 <span class="hlt">tsunamis</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Didenkulova, I.; Pelinovsky, E.</p> <p>2012-04-01</p> <p>Last catastrophic <span class="hlt">tsunami</span> events in Samoa on 29 September 2009 and in Japan on 11 March 2011 demonstrated that <span class="hlt">tsunami</span> may experience abnormal amplification in long bays and firths and result in an unexpectedly high <span class="hlt">wave</span> runup. The capital city Pago Pago, which is located at the toe of a narrow 4-km-long bay and represents the most characteristic example of a long and narrow bay, was considerably damaged during Samoa 2009 <span class="hlt">tsunami</span> (destroyed infrastructures, boats and shipping containers carried inland into commercial areas, etc.) The runup height there reached 8 m over an inundation of 538 m at its toe, while the <span class="hlt">tsunami</span> <span class="hlt">wave</span> height measured by the tide-gauge at the entrance of the bay was at most 3 m. The same situation was observed during catastrophic Tohoku <span class="hlt">tsunami</span> in Japan, which coast contains numerous long bays and firths, which experienced the highest <span class="hlt">wave</span> runup and the strongest amplification. Such examples are villages: Ofunato, Ryori Bay, where the <span class="hlt">wave</span> runup reached 30 m high, and Onagawa, where the <span class="hlt">wave</span> amplified up to 17 m. Here we study the nonlinear dynamics of <span class="hlt">tsunami</span> <span class="hlt">waves</span> in an inclined U-shaped bay. Nonlinear shallow water equations can in this case be written in 1D form and solved analytically with the use of the hodograph transformation. This approach generalizes the well-known Carrier-Greenspan transformation for long <span class="hlt">wave</span> runup on a plane beach. In the case of an inclined U-shaped bay it leads to the associated generalized <span class="hlt">wave</span> equation for symmetrical <span class="hlt">wave</span> in fractal space. In the special case of the channel of parabolic cross-section it is a spherical symmetrical linear <span class="hlt">wave</span> equation. As a result, the solution of the Cauchy problem can be expressed in terms of elementary functions and has a simple form (with respect to analysis) for any kind of initial conditions. <span class="hlt">Wave</span> regimes associated with various localized initial conditions, corresponding to problems of evolution and runup of <span class="hlt">tsunami</span>, are considered and analyzed. Special attention is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFM.S52H..06J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFM.S52H..06J"><span>Regional <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Southeastern United States</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jemberie, A. L.; Langston, C. A.</p> <p>2003-12-01</p> <p>Broad band seismograms from the April 29, 2003, M4.6 Fort Payne, Alabama earthquake are analyzed to infer mechanisms of crustal <span class="hlt">wave</span> <span class="hlt">propagation</span>, crust and upper mantle velocity structure in southeastern United States, and source parameters of the event. In particular, we are interested in producing deterministic models of the distance attenuation of earthquake ground motions through computation of synthetic seismograms. The method first requires constraining the source parameters of an earthquake and then modeling the amplitude and times of broadband arrivals within the waveforms to infer appropriate layered earth models. A first look at seismograms recorded by stations outside the Mississippi Embayment (ME) show clear body phases such P, sP, Pnl, Sn and Lg. The ME signals are qualitatively different from others because they have longer durations and large surface <span class="hlt">waves</span>. A straightforward interpretation of P <span class="hlt">wave</span> arrival times shows a typical upper mantle velocity of 8.18 km/s. However, there is evidence of significantly higher P phase velocities at epicentral distances between 400 and 600km, that may be caused by a high velocity upper mantle anomaly; triplication of P-<span class="hlt">waves</span> is seen in these seismograms. The arrival time differences between regional P and the depth phase sP at different stations are used to constrain the depth of the earthquake. The source depth lies between 9.5 km and 13km which is somewhat more shallow than the network location that was constrained to 15km depth. The Fort Payne earthquake is the largest earthquake to have occurred within the Eastern Tennessee Seismic Zone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19720017699','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19720017699"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in a random medium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lee, R. W.; Harp, J. C.</p> <p>1969-01-01</p> <p>A simple technique is used to derive statistical characterizations of the perturbations imposed upon a <span class="hlt">wave</span> (plane, spherical or beamed) <span class="hlt">propagating</span> through a random medium. The method is essentially physical rather than mathematical, and is probably equivalent to the Rytov method. The limitations of the method are discussed in some detail; in general they are restrictive only for optical paths longer than a few hundred meters, and for paths at the lower microwave frequencies. Situations treated include arbitrary path geometries, finite transmitting and receiving apertures, and anisotropic media. Results include, in addition to the usual statistical quantities, time-lagged functions, mixed functions involving amplitude and phase fluctuations, angle-of-arrival covariances, frequency covariances, and other higher-order quantities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PApGe.168.2043I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PApGe.168.2043I"><span>Anatomy of Historical <span class="hlt">Tsunamis</span>: Lessons Learned for <span class="hlt">Tsunami</span> Warning</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Igarashi, Y.; Kong, L.; Yamamoto, M.; McCreery, C. S.</p> <p>2011-11-01</p> <p><span class="hlt">Tsunamis</span> are high-impact disasters that can cause death and destruction locally within a few minutes of their occurrence and across oceans hours, even up to a day, afterward. Efforts to establish <span class="hlt">tsunami</span> warning systems to protect life and property began in the Pacific after the 1946 Aleutian Islands <span class="hlt">tsunami</span> caused casualties in Hawaii. Seismic and sea level data were used by a central control center to evaluate tsunamigenic potential and then issue alerts and warnings. The ensuing events of 1952, 1957, and 1960 tested the new system, which continued to expand and evolve from a United States system to an international system in 1965. The <span class="hlt">Tsunami</span> Warning System in the Pacific (ITSU) steadily improved through the decades as more stations became available in real and near-real time through better communications technology and greater bandwidth. New analysis techniques, coupled with more data of higher quality, resulted in better detection, greater solution accuracy, and more reliable warnings, but limitations still exist in constraining the source and in accurately predicting <span class="hlt">propagation</span> of the <span class="hlt">wave</span> from source to shore. <span class="hlt">Tsunami</span> event data collected over the last two decades through international <span class="hlt">tsunami</span> science surveys have led to more realistic models for source generation and inundation, and within the warning centers, real-time <span class="hlt">tsunami</span> <span class="hlt">wave</span> forecasting will become a reality in the near future. The <span class="hlt">tsunami</span> warning system is an international cooperative effort amongst countries supported by global and national monitoring networks and dedicated <span class="hlt">tsunami</span> warning centers; the research community has contributed to the system by advancing and improving its analysis tools. Lessons learned from the earliest <span class="hlt">tsunamis</span> provided the backbone for the present system, but despite 45 years of experience, the 2004 Indian Ocean <span class="hlt">tsunami</span> reminded us that <span class="hlt">tsunamis</span> strike and kill everywhere, not just in the Pacific. Today, a global intergovernmental <span class="hlt">tsunami</span> warning system is coordinated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19920006759','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19920006759"><span>Pressure <span class="hlt">wave</span> <span class="hlt">propagation</span> studies for oscillating cascades</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Huff, Dennis L.</p> <p>1992-01-01</p> <p>The unsteady flow field around an oscillating cascade of flat plates is studied using a time marching Euler code. Exact solutions based on linear theory serve as model problems to study pressure <span class="hlt">wave</span> <span class="hlt">propagation</span> in the numerical solution. The importance of using proper unsteady boundary conditions, grid resolution, and time step is demonstrated. Results show that an approximate non-reflecting boundary condition based on linear theory does a good job of minimizing reflections from the inflow and outflow boundaries and allows the placement of the boundaries to be closer than cases using reflective boundary conditions. Stretching the boundary to dampen the unsteady <span class="hlt">waves</span> is another way to minimize reflections. Grid clustering near the plates does a better job of capturing the unsteady flow field than cases using uniform grids as long as the CFL number is less than one for a sufficient portion of the grid. Results for various stagger angles and oscillation frequencies show good agreement with linear theory as long as the grid is properly resolved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992hrl..rept.....G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992hrl..rept.....G"><span>Electromagnetic-<span class="hlt">wave</span> <span class="hlt">propagation</span> in unmagnetized plasmas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gregoire, D. J.; Santoru, J.; Schumacher, R. W.</p> <p>1992-03-01</p> <p>This final report describes an investigation of electromagnetic-<span class="hlt">wave</span> <span class="hlt">propagation</span> in unmagnetized plasmas and its application to the reduction of the radar cross section (RCS) of a plasma-filled enclosure. We have demonstrated RCS reduction of 20 to 25 dB with a prototype system at the radar range at Hughes Aircraft's Microwave Products Division in Torrance. The prototype consists of a sealed ceramic enclosure with a microwave reflector and a plasma generator inside it. When the plasma is present, the RCS is significantly reduced over a frequency range of 4 to 14 GHz. As part of the program, we also investigated the basic-plasma-physics issues relating to the absorption and refraction of electromagnetic (EM) <span class="hlt">waves</span> in collisional plasmas. We demonstrated absorption as high as 63 dB in a section of plasma-loaded C-band rectangular waveguide. We also developed a theoretical model for the plasma cloaking process that includes scattering contributions from the plasma-vacuum interface, partial reflections from the plasma, and collisional absorption in the plasma. The theoretical model is found to be in reasonable agreement with the experimental results and can be used to confidently design future plasma cloaking systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002ASAJ..112.2403M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002ASAJ..112.2403M"><span>Nonlinear magnetoacoustic <span class="hlt">wave</span> <span class="hlt">propagation</span> with chemical reactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Margulies, Timothy Scott</p> <p>2002-11-01</p> <p>The magnetoacoustic problem with an application to sound <span class="hlt">wave</span> <span class="hlt">propagation</span> through electrically conducting fluids such as the ocean in the Earth's magnetic field, liquid metals, or plasmas has been addressed taking into account several simultaneous chemical reactions. Using continuum balance equations for the total mass, linear momentum, energy; as well as Maxwell's electrodynamic equations, a nonlinear beam equation has been developed to generalize the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation for a fluid with linear viscosity but nonlinear and diffraction effects. Thermodynamic parameters are used and not tailored to only an adiabatic fluid case. The chemical kinetic equations build on a relaxing media approach presented, for example, by K. Naugolnukh and L. Ostrovsky [Nonlinear <span class="hlt">Wave</span> Processes in Acoustics (Cambridge Univ. Press, Cambridge, 1998)] for a linearized single reaction and thermodynamic pressure equation of state. Approximations for large and small relaxation times and for magnetohydrodynamic parameters [Korsunskii, Sov. Phys. Acoust. 36 (1990)] are examined. Additionally, Cattaneo's equation for heat conduction and its generalization for a memory process rather than a Fourier's law are taken into account. It was introduced for the heat flux depends on the temperature gradient at an earlier time to generate heat pulses of finite speed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PEPI..230...45A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PEPI..230...45A"><span>Shock <span class="hlt">wave</span> <span class="hlt">propagation</span> in layered planetary embryos</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arkani-Hamed, Jafar; Ivanov, Boris A.</p> <p>2014-05-01</p> <p>The <span class="hlt">propagation</span> of impact-induced shock <span class="hlt">wave</span> inside a planetary embryo is investigated using the Hugoniot equations and a new scaling law, governing the particle velocity variations along a shock ray inside a spherical body. The scaling law is adopted to determine the impact heating of a growing embryo in its early stage when it is an undifferentiated and uniform body. The new scaling law, similar to other existing scaling laws, is not suitable for a large differentiated embryo consisting of a silicate mantle overlying an iron core. An algorithm is developed in this study on the basis of the ray theory in a spherically symmetric body which relates the shock parameters at the top of the core to those at the base of the mantle, thus enabling the adoption of scaling laws to estimate the impact heating of both the mantle and the core. The algorithm is applied to two embryo models: a simple two-layered model with a uniform mantle overlying a uniform core, and a model where the pre-shock density and acoustic velocity of the embryo are radially dependent. The former illustrates details of the particle velocity, shock pressure, and temperature increase behind the shock front in a 2D axisymmetric geometry. The latter provides a means to compare the results with those obtained by a hydrocode simulation. The agreement between the results of the two techniques in revealing the effects of the core-mantle boundary on the shock <span class="hlt">wave</span> transmission across the boundary is encouraging.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70036889','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70036889"><span>Hydrodynamic modeling of <span class="hlt">tsunamis</span> from the Currituck landslide</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, E.L.; Lynett, P.J.; Chaytor, J.D.</p> <p>2009-01-01</p> <p><span class="hlt">Tsunami</span> generation from the Currituck landslide offshore North Carolina and <span class="hlt">propagation</span> of <span class="hlt">waves</span> toward the U.S. coastline are modeled based on recent geotechnical analysis of slide movement. A long and intermediate <span class="hlt">wave</span> modeling package (COULWAVE) based on the non-linear Boussinesq equations are used to simulate the <span class="hlt">tsunami</span>. This model includes procedures to incorporate bottom friction, <span class="hlt">wave</span> breaking, and overland flow during runup. Potential <span class="hlt">tsunamis</span> generated from the Currituck landslide are analyzed using four approaches: (1) <span class="hlt">tsunami</span> <span class="hlt">wave</span> history is calculated from several different scenarios indicated by geotechnical stability and mobility analyses; (2) a sensitivity analysis is conducted to determine the effects of both landslide failure duration during generation and bottom friction along the continental shelf during <span class="hlt">propagation</span>; (3) <span class="hlt">wave</span> history is calculated over a regional area to determine the <span class="hlt">propagation</span> of energy oblique to the slide axis; and (4) a high-resolution 1D model is developed to accurately model <span class="hlt">wave</span> breaking and the combined influence of nonlinearity and dispersion during nearshore <span class="hlt">propagation</span> and runup. The primary source parameter that affects <span class="hlt">tsunami</span> severity for this case study is landslide volume, with failure duration having a secondary influence. Bottom friction during <span class="hlt">propagation</span> across the continental shelf has a strong influence on the attenuation of the <span class="hlt">tsunami</span> during <span class="hlt">propagation</span>. The high-resolution 1D model also indicates that the <span class="hlt">tsunami</span> undergoes nonlinear fission prior to <span class="hlt">wave</span> breaking, generating independent, short-period <span class="hlt">waves</span>. <span class="hlt">Wave</span> breaking occurs approximately 40-50??km offshore where a <span class="hlt">tsunami</span> bore is formed that persists during runup. These analyses illustrate the complex nature of landslide <span class="hlt">tsunamis</span>, necessitating the use of detailed landslide stability/mobility models and higher-order hydrodynamic models to determine their hazard.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1912891R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1912891R"><span>Combining historical eyewitness accounts on <span class="hlt">tsunami</span>-induced <span class="hlt">waves</span> and numerical simulations for getting insights in uncertainty of source parameters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rohmer, Jeremy; Rousseau, Marie; Lemoine, Anne; Pedreros, Rodrigo; Lambert, Jerome; benki, Aalae</p> <p>2017-04-01</p> <p>Recent <span class="hlt">tsunami</span> events including the 2004 Indian Ocean <span class="hlt">tsunami</span> and the 2011 Tohoku <span class="hlt">tsunami</span> have caused many casualties and damages to structures. Advances in numerical simulation of <span class="hlt">tsunami</span>-induced <span class="hlt">wave</span> processes have tremendously improved forecast, hazard and risk assessment and design of early warning for <span class="hlt">tsunamis</span>. Among the major challenges, several studies have underlined uncertainties in earthquake slip distributions and rupture processes as major contributor on <span class="hlt">tsunami</span> <span class="hlt">wave</span> height and inundation extent. Constraining these uncertainties can be performed by taking advantage of observations either on <span class="hlt">tsunami</span> <span class="hlt">waves</span> (using network of water level gauge) or on inundation characteristics (using field evidence and eyewitness accounts). Despite these successful applications, combining <span class="hlt">tsunami</span> observations and simulations still faces several limitations when the problem is addressed for past <span class="hlt">tsunamis</span> events like 1755 Lisbon. 1) While recent inversion studies can benefit from current modern networks (e.g., tide gauges, sea bottom pressure gauges, GPS-mounted buoys), the number of tide gauges can be very scarce and testimonies on <span class="hlt">tsunami</span> observations can be limited, incomplete and imprecise for past <span class="hlt">tsunamis</span> events. These observations often restrict to eyewitness accounts on <span class="hlt">wave</span> heights (e.g., maximum reached <span class="hlt">wave</span> height at the coast) instead of the full observed waveforms; 2) <span class="hlt">Tsunami</span> phenomena involve a large span of spatial scales (from ocean basin scales to local coastal <span class="hlt">wave</span> interactions), which can make the modelling very demanding: the computation time cost of <span class="hlt">tsunami</span> simulation can be very prohibitive; often reaching several hours. This often limits the number of allowable long-running simulations for performing the inversion, especially when the problem is addressed from a Bayesian inference perspective. The objective of the present study is to overcome both afore-described difficulties in the view to combine historical observations on past <span class="hlt">tsunami</span>-induced <span class="hlt">waves</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018SedG..364..242L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018SedG..364..242L"><span>Boulder emplacement and remobilisation by cyclone and submarine landslide <span class="hlt">tsunami</span> <span class="hlt">waves</span> near Suva City, Fiji</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lau, A. Y. Annie; Terry, James P.; Ziegler, Alan; Pratap, Arti; Harris, Daniel</p> <p>2018-02-01</p> <p>The characteristics of a reef-top boulder field created by a local submarine landslide <span class="hlt">tsunami</span> are presented for the first time. Our examination of large reef-derived boulders deposited by the 1953 <span class="hlt">tsunami</span> near Suva City, Fiji, revealed that shorter-than-normal-period <span class="hlt">tsunami</span> <span class="hlt">waves</span> generated by submarine landslides can create a boulder field resembling a storm boulder field due to relatively short boulder transport distances. The boulder-inferred 1953 <span class="hlt">tsunami</span> flow velocity is estimated at over 9 m s- 1 at the reef edge. Subsequent events, for example Cyclone Kina (1993), appear to have remobilised some large boulders. While prior research has demonstrated headward retreat of Suva Canyon in response to the repeated occurrence of earthquakes over the past few millennia, our results highlight the lingering vulnerability of the Fijian coastlines to high-energy <span class="hlt">waves</span> generated both in the presence (<span class="hlt">tsunami</span>) and absence (storm) of submarine failures and/or earthquakes. To explain the age discrepancies of U-Th dated coral comprising the deposited boulders, we introduce a conceptual model showing the role of repeated episodes of tsunamigenic submarine landslides in removing reef front sections through collapse. Subsequent high-energy <span class="hlt">wave</span> events transport boulders from exposed older sections of the reef front onto the reef where they are deposited as 'new' boulders, alongside freshly detached sections of the living reef. In similar situations where anachronistic deposits complicate the deposition signal, age-dating of the coral boulders should not be used as a proxy for determining the timing of the submarine landslides or the <span class="hlt">tsunamis</span> that generated them.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70173968','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70173968"><span>Beat-the-<span class="hlt">wave</span> evacuation mapping for <span class="hlt">tsunami</span> hazards in Seaside, Oregon, USA</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Priest, George R.; Stimely, Laura; Wood, Nathan J.; Madin, Ian; Watzig, Rudie</p> <p>2016-01-01</p> <p>Previous pedestrian evacuation modeling for <span class="hlt">tsunamis</span> has not considered variable <span class="hlt">wave</span> arrival times or critical junctures (e.g., bridges), nor does it effectively communicate multiple evacuee travel speeds. We summarize an approach that identifies evacuation corridors, recognizes variable <span class="hlt">wave</span> arrival times, and produces a map of minimum pedestrian travel speeds to reach safety, termed a “beat-the-wave” (BTW) evacuation analysis. We demonstrate the improved approach by evaluating difficulty of pedestrian evacuation of Seaside, Oregon, for a local <span class="hlt">tsunami</span> generated by a Cascadia subduction zone earthquake. We establish evacuation paths by calculating the least cost distance (LCD) to safety for every grid cell in a <span class="hlt">tsunami</span>-hazard zone using geospatial, anisotropic path distance algorithms. Minimum BTW speed to safety on LCD paths is calculated for every grid cell by dividing surface distance from that cell to safety by the <span class="hlt">tsunami</span> arrival time at safety. We evaluated three scenarios of evacuation difficulty: (1) all bridges are intact with a 5-minute evacuation delay from the start of earthquake, (2) only retrofitted bridges are considered intact with a 5-minute delay, and (3) only retrofitted bridges are considered intact with a 10-minute delay. BTW maps also take into account critical evacuation points along complex shorelines (e.g., peninsulas, bridges over shore-parallel estuaries) where evacuees could be caught by <span class="hlt">tsunami</span> <span class="hlt">waves</span>. The BTW map is able to communicate multiple pedestrian travel speeds, which are typically visualized by multiple maps with current LCD-based mapping practices. Results demonstrate that evacuation of Seaside is problematic seaward of the shore-parallel waterways for those with any limitations on mobility. <span class="hlt">Tsunami</span> vertical-evacuation refuges or additional pedestrian bridges may be effective ways of reducing loss of life seaward of these waterways.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22561929','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22561929"><span>Common omissions and misconceptions of <span class="hlt">wave</span> <span class="hlt">propagation</span> in turbulence: discussion.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Charnotskii, Mikhail</p> <p>2012-05-01</p> <p>This review paper addresses typical mistakes and omissions that involve theoretical research and modeling of optical <span class="hlt">propagation</span> through atmospheric turbulence. We discuss the disregard of some general properties of narrow-angle <span class="hlt">propagation</span> in refractive random media, the careless use of simplified models of turbulence, and omissions in the calculations of the second moment of the <span class="hlt">propagating</span> <span class="hlt">wave</span>. We also review some misconceptions regarding short-exposure imaging, <span class="hlt">propagation</span> of polarized <span class="hlt">waves</span>, and calculations of the scintillation index of the beam <span class="hlt">waves</span>. © 2012 Optical Society of America</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880015884','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880015884"><span>Linear and nonlinear acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span> in the atmosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hariharan, S. I.; Yu, Ping</p> <p>1988-01-01</p> <p>The investigation of the acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span> theory and numerical implementation for the situation of an isothermal atmosphere is described. A one-dimensional model to validate an asymptotic theory and a 3-D situation to relate to a realistic situation are considered. In addition, nonlinear <span class="hlt">wave</span> <span class="hlt">propagation</span> and the numerical treatment are included. It is known that the gravitational effects play a crucial role in the low frequency acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span>. They <span class="hlt">propagate</span> large distances and, as such, the numerical treatment of those problems become difficult in terms of posing boundary conditions which are valid for all frequencies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170009019','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170009019"><span>Properties, <span class="hlt">Propagation</span>, and Excitation of EMIC <span class="hlt">Waves</span> Properties, <span class="hlt">Propagation</span>, and Excitation of EMIC <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zhang, Jichun; Coffey, Victoria N.; Chandler, Michael O.; Boardsen, Scott A.; Saikin, Anthony A.; Mello, Emily M.; Russell, Christopher T.; Torbert, Roy B.; Fuselier, Stephen A.; Giles, Barbara L.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20170009019'); toggleEditAbsImage('author_20170009019_show'); toggleEditAbsImage('author_20170009019_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20170009019_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170009019_hide"></p> <p>2017-01-01</p> <p>Electromagnetic ion cyclotron (EMIC) <span class="hlt">waves</span> (0.1-5 Hz) play an important role in particle dynamics in the Earth's magnetosphere. EMIC <span class="hlt">waves</span> are preferentially excited in regions where hot anisotropic ions and cold dense plasma populations spatially overlap. While the generation region of EMIC <span class="hlt">waves</span> is usually on or near the magnetic equatorial plane in the inner magnetosphere, EMIC <span class="hlt">waves</span> have both equatorial and off-equator source regions on the dayside in the compressed outer magnetosphere. Using field and plasma measurements from the Magnetospheric Multiscale (MMS) mission, we perform a case study of EMIC <span class="hlt">waves</span> and associated local plasma conditions observed on 19 October 2015. From 0315 to 0810 UT, before crossing the magnetopause into the magnetosheath, all four MMS spacecraft detected long-lasting He(exp +)-band EMIC <span class="hlt">wave</span> emissions around local noon (MLT = 12.7 - 14.0) at high L-shells (L = 8.8 - 15.2) and low magnetic latitudes (MLAT = -21.8deg - -30.3deg). Energetic (greater than 1 keV) and anisotropic ions were present throughout this event that was in the recovery phase of a weak geomagnetic storm (min. Dst = -48 nT at 1000 UT on 18 October 2015). The testing of linear theory suggests that the EMIC <span class="hlt">waves</span> were excited locally. Although the <span class="hlt">wave</span> event is dominated by small normal angles, its polarization is mixed with right- and left-handedness and its <span class="hlt">propagation</span> is bi-directional with regard to the background magnetic field. The short inter-spacecraft distances (as low as 15 km) of the MMS mission make it possible to accurately determine the k vector of the <span class="hlt">waves</span> using the phase difference technique. Preliminary analysis finds that the k vector magnitude, phase speed, and wavelength of the 0.3-Hz <span class="hlt">wave</span> packet at 0453:55 UT are 0.005 km(exp -1), 372.9 km/s, and 1242.9 km, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH33B2783T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH33B2783T"><span><span class="hlt">Wave</span> <span class="hlt">Propagation</span> Around Coronal Structures: Stratification, Buoyancy, Small Scale Formation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tomlinson, S. M.; Rappazzo, F.; Velli, M.</p> <p>2017-12-01</p> <p>We study the <span class="hlt">propagation</span> of <span class="hlt">waves</span> in a coronal medium characterized by stratification and structure in density. temperature and magnetic field. It is well known that average gradients affect the <span class="hlt">propagation</span> of Alfvén and other MHD <span class="hlt">waves</span> via reflection, phase mixing, resonant absorption and other coupling phenomena. Here we discuss how the interplay of <span class="hlt">propagation</span> on inhomogeneous, stratified structures with nonlinear interactions may lead to interesting effects including preferential heating, buoyancy, and plasma acceleration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008GeoRL..3510604F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008GeoRL..3510604F"><span>The 15 August 2007 Peru <span class="hlt">tsunami</span> runup observations and modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fritz, Hermann M.; Kalligeris, Nikos; Borrero, Jose C.; Broncano, Pablo; Ortega, Erick</p> <p>2008-05-01</p> <p>On 15 August 2007 an earthquake with moment magnitude (Mw) of 8.0 centered off the coast of central Peru, generated a <span class="hlt">tsunami</span> with locally focused runup heights of up to10 m. A reconnaissance team was deployed two weeks after the event and investigated the <span class="hlt">tsunami</span> effects at 51 sites. Three <span class="hlt">tsunami</span> fatalities were reported south of the Paracas Peninsula in a sparsely populated desert area where the largest <span class="hlt">tsunami</span> runup heights were measured. Numerical modeling of the earthquake source and <span class="hlt">tsunami</span> suggest that a region of high slip near the coastline was primarily responsible for the extreme runup heights. The town of Pisco was spared by the Paracas Peninsula, which blocked <span class="hlt">tsunami</span> <span class="hlt">waves</span> from <span class="hlt">propagating</span> northward from the high slip region. The coast of Peru has experienced numerous deadly and destructive <span class="hlt">tsunamis</span> throughout history, which highlights the importance of ongoing <span class="hlt">tsunami</span> awareness and education efforts to ensure successful self-evacuation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1811285M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1811285M"><span>Scenario based <span class="hlt">tsunami</span> <span class="hlt">wave</span> height estimation towards hazard evaluation for the Hellenic coastline and examples of extreme inundation zones in South Aegean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Melis, Nikolaos S.; Barberopoulou, Aggeliki; Frentzos, Elias; Krassanakis, Vassilios</p> <p>2016-04-01</p> <p>A scenario based methodology for <span class="hlt">tsunami</span> hazard assessment is used, by incorporating earthquake sources with the potential to produce extreme <span class="hlt">tsunamis</span> (measured through their capacity to cause maximum <span class="hlt">wave</span> height and inundation extent). In the present study we follow a two phase approach. In the first phase, existing earthquake hazard zoning in the greater Aegean region is used to derive representative maximum expected earthquake magnitude events, with realistic seismotectonic source characteristics, and of greatest tsunamigenic potential within each zone. By stacking the scenario produced maximum <span class="hlt">wave</span> heights a global maximum map is constructed for the entire Hellenic coastline, corresponding to all expected extreme offshore earthquake sources. Further evaluation of the produced coastline categories based on the maximum expected <span class="hlt">wave</span> heights emphasizes the <span class="hlt">tsunami</span> hazard in selected coastal zones with important functions (i.e. touristic crowded zones, industrial zones, airports, power plants etc). Owing to its proximity to the Hellenic Arc, many urban centres and being a popular tourist destination, Crete Island and the South Aegean region are given a top priority to define extreme inundation zoning. In the second phase, a set of four large coastal cities (Kalamata, Chania, Heraklion and Rethymno), important for <span class="hlt">tsunami</span> hazard, due i.e. to the crowded beaches during the summer season or industrial facilities, are explored towards preparedness and resilience for <span class="hlt">tsunami</span> hazard in Greece. To simulate <span class="hlt">tsunamis</span> in the Aegean region (generation, <span class="hlt">propagation</span> and runup) the MOST - ComMIT NOAA code was used. High resolution DEMs for bathymetry and topography were joined via an interface, specifically developed for the inundation maps in this study and with similar products in mind. For the examples explored in the present study, we used 5m resolution for the topography and 30m resolution for the bathymetry, respectively. Although this study can be considered as</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70021726','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70021726"><span><span class="hlt">Wave-propagation</span> formulation of seismic response of multistory buildings</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Safak, E.</p> <p>1999-01-01</p> <p>This paper presents a discrete-time <span class="hlt">wave-propagation</span> method to calculate the seismic response of multistory buildings, founded on layered soil media and subjected to vertically <span class="hlt">propagating</span> shear <span class="hlt">waves</span>. Buildings are modeled as an extension of the layered soil media by considering each story as another layer in the <span class="hlt">wave-propagation</span> path. The seismic response is expressed in terms of <span class="hlt">wave</span> travel times between the layers and <span class="hlt">wave</span> reflection and transmission coefficients at layer interfaces. The method accounts for the filtering effects of the concentrated foundation and floor masses. Compared with commonly used vibration formulation, the <span class="hlt">wave-propagation</span> formulation provides several advantages, including simplicity, improved accuracy, better representation of damping, the ability to incorporate the soil layers under the foundation, and providing better tools for identification and damage detection from seismic records. Examples are presented to show the versatility and the superiority of the method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27196957','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27196957"><span><span class="hlt">Tsunami</span> <span class="hlt">waves</span> extensively resurfaced the shorelines of an early Martian ocean.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rodriguez, J Alexis P; Fairén, Alberto G; Tanaka, Kenneth L; Zarroca, Mario; Linares, Rogelio; Platz, Thomas; Komatsu, Goro; Miyamoto, Hideaki; Kargel, Jeffrey S; Yan, Jianguo; Gulick, Virginia; Higuchi, Kana; Baker, Victor R; Glines, Natalie</p> <p>2016-05-19</p> <p>It has been proposed that ~3.4 billion years ago an ocean fed by enormous catastrophic floods covered most of the Martian northern lowlands. However, a persistent problem with this hypothesis is the lack of definitive paleoshoreline features. Here, based on geomorphic and thermal image mapping in the circum-Chryse and northwestern Arabia Terra regions of the northern plains, in combination with numerical analyses, we show evidence for two enormous <span class="hlt">tsunami</span> events possibly triggered by bolide impacts, resulting in craters ~30 km in diameter and occurring perhaps a few million years apart. The <span class="hlt">tsunamis</span> produced widespread littoral landforms, including run-up water-ice-rich and bouldery lobes, which extended tens to hundreds of kilometers over gently sloping plains and boundary cratered highlands, as well as backwash channels where <span class="hlt">wave</span> retreat occurred on highland-boundary surfaces. The ice-rich lobes formed in association with the younger <span class="hlt">tsunami</span>, showing that their emplacement took place following a transition into a colder global climatic regime that occurred after the older <span class="hlt">tsunami</span> event. We conclude that, on early Mars, <span class="hlt">tsunamis</span> played a major role in generating and resurfacing coastal terrains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4872529','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4872529"><span><span class="hlt">Tsunami</span> <span class="hlt">waves</span> extensively resurfaced the shorelines of an early Martian ocean</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Rodriguez, J. Alexis P.; Fairén, Alberto G.; Tanaka, Kenneth L.; Zarroca, Mario; Linares, Rogelio; Platz, Thomas; Komatsu, Goro; Miyamoto, Hideaki; Kargel, Jeffrey S.; Yan, Jianguo; Gulick, Virginia; Higuchi, Kana; Baker, Victor R.; Glines, Natalie</p> <p>2016-01-01</p> <p>It has been proposed that ~3.4 billion years ago an ocean fed by enormous catastrophic floods covered most of the Martian northern lowlands. However, a persistent problem with this hypothesis is the lack of definitive paleoshoreline features. Here, based on geomorphic and thermal image mapping in the circum-Chryse and northwestern Arabia Terra regions of the northern plains, in combination with numerical analyses, we show evidence for two enormous <span class="hlt">tsunami</span> events possibly triggered by bolide impacts, resulting in craters ~30 km in diameter and occurring perhaps a few million years apart. The <span class="hlt">tsunamis</span> produced widespread littoral landforms, including run-up water-ice-rich and bouldery lobes, which extended tens to hundreds of kilometers over gently sloping plains and boundary cratered highlands, as well as backwash channels where <span class="hlt">wave</span> retreat occurred on highland-boundary surfaces. The ice-rich lobes formed in association with the younger <span class="hlt">tsunami</span>, showing that their emplacement took place following a transition into a colder global climatic regime that occurred after the older <span class="hlt">tsunami</span> event. We conclude that, on early Mars, <span class="hlt">tsunamis</span> played a major role in generating and resurfacing coastal terrains. PMID:27196957</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/15013458','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/15013458"><span><span class="hlt">Propagation</span> of Axially Symmetric Detonation <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Druce, R L; Roeske, F; Souers, P C</p> <p>2002-06-26</p> <p>We have studied the non-ideal <span class="hlt">propagation</span> of detonation <span class="hlt">waves</span> in LX-10 and in the insensitive explosive TATB. Explosively-driven, 5.8-mm-diameter, 0.125-mm-thick aluminum flyer plates were used to initiate 38-mm-diameter, hemispherical samples of LX-10 pressed to a density of 1.86 g/cm{sup 3} and of TATB at a density of 1.80 g/cm{sup 3}. The TATB powder was a grade called ultrafine (UFTATB), having an arithmetic mean particle diameter of about 8-10 {micro}m and a specific surface area of about 4.5 m{sup 2}/g. Using PMMA as a transducer, output pressure was measured at 5 discrete points on the booster using a Fabry-Perot velocimeter. Breakoutmore » time was measured on a line across the booster with a streak camera. Each of the experimental geometries was calculated using the Ignition and Growth Reactive Flow Model, the JWL++ Model and the Programmed Burn Model. Boosters at both ambient and cold (-20 C and -54 C) temperatures have been experimentally and computationally studied. A comparison of experimental and modeling results is presented.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRB..119.5574Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRB..119.5574Y"><span>Rupture process of the 2010 Mw 7.8 Mentawai <span class="hlt">tsunami</span> earthquake from joint inversion of near-field hr-GPS and teleseismic body <span class="hlt">wave</span> recordings constrained by <span class="hlt">tsunami</span> observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yue, Han; Lay, Thorne; Rivera, Luis; Bai, Yefei; Yamazaki, Yoshiki; Cheung, Kwok Fai; Hill, Emma M.; Sieh, Kerry; Kongko, Widjo; Muhari, Abdul</p> <p>2014-07-01</p> <p>The 25 October 2010 Mentawai <span class="hlt">tsunami</span> earthquake (Mw 7.8) ruptured the shallow portion of the Sunda megathrust seaward of the Mentawai Islands, offshore of Sumatra, Indonesia, generating a strong <span class="hlt">tsunami</span> that took 509 lives. The rupture zone was updip of those of the 12 September 2007 Mw 8.5 and 7.9 underthrusting earthquakes. High-rate (1 s sampling) GPS instruments of the Sumatra GPS Array network deployed on the Mentawai Islands and Sumatra mainland recorded time-varying and static ground displacements at epicentral distances from 49 to 322 km. Azimuthally distributed <span class="hlt">tsunami</span> recordings from two deepwater sensors and two tide gauges that have local high-resolution bathymetric information provide additional constraints on the source process. Finite-fault rupture models, obtained by joint inversion of the high-rate (hr)-GPS time series and numerous teleseismic broadband P and S <span class="hlt">wave</span> seismograms together with iterative forward modeling of the <span class="hlt">tsunami</span> recordings, indicate rupture <span class="hlt">propagation</span> ~50 km up dip and ~100 km northwest along strike from the hypocenter, with a rupture velocity of ~1.8 km/s. Subregions with large slip extend from 7 to 10 km depth ~80 km northwest from the hypocenter with a maximum slip of 8 m and from ~5 km depth to beneath thin horizontal sedimentary layers beyond the prism deformation front for ~100 km along strike, with a localized region having >15 m of slip. The seismic moment is 7.2 × 1020 N m. The rupture model indicates that local heterogeneities in the shallow megathrust can accumulate strain that allows some regions near the toe of accretionary prisms to fail in <span class="hlt">tsunami</span> earthquakes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH22A..01T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH22A..01T"><span><span class="hlt">Tsunami</span> <span class="hlt">waves</span> generated by dynamically triggered aftershocks of the 2010 Haiti earthquake</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ten Brink, U. S.; Wei, Y.; Fan, W.; Miller, N. C.; Granja, J. L.</p> <p>2017-12-01</p> <p>Dynamically-triggered aftershocks, thought to be set off by the passage of surface <span class="hlt">waves</span>, are currently not considered in <span class="hlt">tsunami</span> warnings, yet may produce enough seafloor deformation to generate <span class="hlt">tsunamis</span> on their own, as judged from new findings about the January 12, 2010 Haiti earthquake <span class="hlt">tsunami</span> in the Caribbean Sea. This <span class="hlt">tsunami</span> followed the Mw7.0 Haiti mainshock, which resulted from a complex rupture along the north shore of Tiburon Peninsula, not beneath the Caribbean Sea. The mainshock, moreover, had a mixed strike-slip and thrust focal mechanism. There were no recorded aftershocks in the Caribbean Sea, only small coastal landslides and rock falls on the south shore of Tiburon Peninsula. Nevertheless, a <span class="hlt">tsunami</span> was recorded on deep-sea DART buoy 42407 south of the Dominican Republic and on the Santo Domingo tide gauge, and run-ups of ≤3 m were observed along a 90-km-long stretch of the SE Haiti coast. Three dynamically-triggered aftershocks south of Haiti have been recently identified within the coda of the mainshock (<200 s) by analyzing P <span class="hlt">wave</span> arrivals recorded by dense seismic arrays, parsing the arrivals into 20-s-long stacks, and back-projecting the arrivals to the vicinity of the main shock (50-300 km). Two of the aftershocks, coming 20-40 s and 40-60 s after the mainshock, plot along NW-SE-trending submarine ridges in the Caribbean Sea south of Haiti. The third event, 120-140 s was located along the steep eastern slope of Bahoruco Peninsula, which is delineated by a normal fault. Forward <span class="hlt">tsunami</span> models show that the arrival times of the DART buoy and tide gauge times are best fit by the earliest of the three aftershocks, with a Caribbean source 60 km SW of the mainshock rupture zone. Preliminary inversion of the DART buoy time series for fault locations and orientations confirms the location of the first source, but requires an additional unidentified source closer to shore 40 km SW of the mainshock rupture zone. This overall agreement between</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRC..121.7701B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRC..121.7701B"><span><span class="hlt">Tsunami</span> generation and associated <span class="hlt">waves</span> in the water column and seabed due to an asymmetric earthquake motion within an anisotropic substratum</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bagheri, Amirhossein; Greenhalgh, Stewart; Khojasteh, Ali; Rahimian, Mohammad; Attarnejad, Reza</p> <p>2016-10-01</p> <p>In this paper, closed-form integral expressions are derived to describe how surface gravity <span class="hlt">waves</span> (<span class="hlt">tsunamis</span>) are generated when general asymmetric ground displacement (due to earthquake rupturing), involving both horizontal and vertical components of motion, occurs at arbitrary depth within the interior of an anisotropic subsea solid beneath the ocean. In addition, we compute the resultant hydrodynamic pressure within the seawater and the elastic wavefield within the seabed at any position. The method of potential functions and an integral transform approach, accompanied by a special contour integration scheme, are adopted to handle the equations of motion and produce the numerical results. The formulation accounts for any number of possible acoustic-gravity modes and is valid for both shallow and deep water situations as well as for any focal depth of the earthquake source. Phase and group velocity dispersion curves are developed for surface gravity (<span class="hlt">tsunami</span> mode), acoustic-gravity, Rayleigh, and Scholte <span class="hlt">waves</span>. Several asymptotic cases which arise from the general analysis are discussed and compared to existing solutions. The role of effective parameters such as hypocenter location and frequency of excitation is examined and illustrated through several figures which show the <span class="hlt">propagation</span> pattern in the vertical and horizontal directions. Attention is directed to the unexpected contribution from the horizontal ground motion. The results have important application in several fields such as <span class="hlt">tsunami</span> hazard prediction, marine seismology, and offshore and coastal engineering. In a companion paper, we examine the effect of ocean stratification on the appearance and character of internal and surface gravity <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EP%26S...69..117L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EP%26S...69..117L"><span>Should <span class="hlt">tsunami</span> simulations include a nonzero initial horizontal velocity?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lotto, Gabriel C.; Nava, Gabriel; Dunham, Eric M.</p> <p>2017-08-01</p> <p><span class="hlt">Tsunami</span> <span class="hlt">propagation</span> in the open ocean is most commonly modeled by solving the shallow water <span class="hlt">wave</span> equations. These equations require initial conditions on sea surface height and depth-averaged horizontal particle velocity or, equivalently, horizontal momentum. While most modelers assume that initial velocity is zero, Y.T. Song and collaborators have argued for nonzero initial velocity, claiming that horizontal displacement of a sloping seafloor imparts significant horizontal momentum to the ocean. They show examples in which this effect increases the resulting <span class="hlt">tsunami</span> height by a factor of two or more relative to models in which initial velocity is zero. We test this claim with a "full-physics" integrated dynamic rupture and <span class="hlt">tsunami</span> model that couples the elastic response of the Earth to the linearized acoustic-gravitational response of a compressible ocean with gravity; the model self-consistently accounts for seismic <span class="hlt">waves</span> in the solid Earth, acoustic <span class="hlt">waves</span> in the ocean, and <span class="hlt">tsunamis</span> (with dispersion at short wavelengths). Full-physics simulations of subduction zone megathrust ruptures and <span class="hlt">tsunamis</span> in geometries with a sloping seafloor confirm that substantial horizontal momentum is imparted to the ocean. However, almost all of that initial momentum is carried away by ocean acoustic <span class="hlt">waves</span>, with negligible momentum imparted to the <span class="hlt">tsunami</span>. We also compare <span class="hlt">tsunami</span> <span class="hlt">propagation</span> in each simulation to that predicted by an equivalent shallow water <span class="hlt">wave</span> simulation with varying assumptions regarding initial velocity. We find that the initial horizontal velocity conditions proposed by Song and collaborators consistently overestimate the <span class="hlt">tsunami</span> amplitude and predict an inconsistent <span class="hlt">wave</span> profile. Finally, we determine <span class="hlt">tsunami</span> initial conditions that are rigorously consistent with our full-physics simulations by isolating the <span class="hlt">tsunami</span> <span class="hlt">waves</span> from ocean acoustic and seismic <span class="hlt">waves</span> at some final time, and backpropagating the <span class="hlt">tsunami</span> <span class="hlt">waves</span> to their initial state by solving the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SMaS...26l5027C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SMaS...26l5027C"><span><span class="hlt">Propagation</span> and dispersion of shock <span class="hlt">waves</span> in magnetoelastic materials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Crum, R. S.; Domann, J. P.; Carman, G. P.; Gupta, V.</p> <p>2017-12-01</p> <p>Previous studies examining the response of magnetoelastic materials to shock <span class="hlt">waves</span> have predominantly focused on applications involving pulsed power generation, with limited attention given to the actual <span class="hlt">wave</span> <span class="hlt">propagation</span> characteristics. This study provides detailed magnetic and mechanical measurements of magnetoelastic shock <span class="hlt">wave</span> <span class="hlt">propagation</span> and dispersion. Laser generated rarefacted shock <span class="hlt">waves</span> exceeding 3 GPa with rise times of 10 ns were introduced to samples of the magnetoelastic material Galfenol. The resulting mechanical measurements reveal the evolution of the shock into a compressive acoustic front with lateral release <span class="hlt">waves</span>. Importantly, the <span class="hlt">wave</span> continues to disperse even after it has decayed into an acoustic <span class="hlt">wave</span>, due in large part to magnetoelastic coupling. The magnetic data reveal predominantly shear <span class="hlt">wave</span> mediated magnetoelastic coupling, and were also used to noninvasively measure the <span class="hlt">wave</span> speed. The external magnetic field controlled a 30% increase in <span class="hlt">wave</span> <span class="hlt">propagation</span> speed, attributed to a 70% increase in average stiffness. Finally, magnetic signals <span class="hlt">propagating</span> along the sample over 20× faster than the mechanical <span class="hlt">wave</span> were measured, indicating these materials can act as passive antennas that transmit information in response to mechanical stimuli.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1418915-propagation-dispersion-shock-waves-magnetoelastic-materials','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1418915-propagation-dispersion-shock-waves-magnetoelastic-materials"><span><span class="hlt">Propagation</span> and dispersion of shock <span class="hlt">waves</span> in magnetoelastic materials</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Crum, R. S.; Domann, J. P.; Carman, G. P.</p> <p></p> <p>Previous studies examining the response of magnetoelastic materials to shock <span class="hlt">waves</span> have predominantly focused on applications involving pulsed power generation, with limited attention given to the actual <span class="hlt">wave</span> <span class="hlt">propagation</span> characteristics. This study provides detailed magnetic and mechanical measurements of magnetoelastic shock <span class="hlt">wave</span> <span class="hlt">propagation</span> and dispersion. Laser generated rarefacted shock <span class="hlt">waves</span> exceeding 3 GPa with rise times of 10 ns were introduced to samples of the magnetoelastic material Galfenol. The resulting mechanical measurements reveal the evolution of the shock into a compressive acoustic front with lateral release <span class="hlt">waves</span>. Importantly, the <span class="hlt">wave</span> continues to disperse even after it has decayed into anmore » acoustic <span class="hlt">wave</span>, due in large part to magnetoelastic coupling. The magnetic data reveal predominantly shear <span class="hlt">wave</span> mediated magnetoelastic coupling, and were also used to noninvasively measure the <span class="hlt">wave</span> speed. The external magnetic field controlled a 30% increase in <span class="hlt">wave</span> <span class="hlt">propagation</span> speed, attributed to a 70% increase in average stiffness. Lastly, magnetic signals <span class="hlt">propagating</span> along the sample over 20× faster than the mechanical <span class="hlt">wave</span> were measured, indicating these materials can act as passive antennas that transmit information in response to mechanical stimuli.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1418915-propagation-dispersion-shock-waves-magnetoelastic-materials','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1418915-propagation-dispersion-shock-waves-magnetoelastic-materials"><span><span class="hlt">Propagation</span> and dispersion of shock <span class="hlt">waves</span> in magnetoelastic materials</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Crum, R. S.; Domann, J. P.; Carman, G. P.; ...</p> <p>2017-11-15</p> <p>Previous studies examining the response of magnetoelastic materials to shock <span class="hlt">waves</span> have predominantly focused on applications involving pulsed power generation, with limited attention given to the actual <span class="hlt">wave</span> <span class="hlt">propagation</span> characteristics. This study provides detailed magnetic and mechanical measurements of magnetoelastic shock <span class="hlt">wave</span> <span class="hlt">propagation</span> and dispersion. Laser generated rarefacted shock <span class="hlt">waves</span> exceeding 3 GPa with rise times of 10 ns were introduced to samples of the magnetoelastic material Galfenol. The resulting mechanical measurements reveal the evolution of the shock into a compressive acoustic front with lateral release <span class="hlt">waves</span>. Importantly, the <span class="hlt">wave</span> continues to disperse even after it has decayed into anmore » acoustic <span class="hlt">wave</span>, due in large part to magnetoelastic coupling. The magnetic data reveal predominantly shear <span class="hlt">wave</span> mediated magnetoelastic coupling, and were also used to noninvasively measure the <span class="hlt">wave</span> speed. The external magnetic field controlled a 30% increase in <span class="hlt">wave</span> <span class="hlt">propagation</span> speed, attributed to a 70% increase in average stiffness. Lastly, magnetic signals <span class="hlt">propagating</span> along the sample over 20× faster than the mechanical <span class="hlt">wave</span> were measured, indicating these materials can act as passive antennas that transmit information in response to mechanical stimuli.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998P%26SS...47..273S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998P%26SS...47..273S"><span>Low frequency <span class="hlt">wave</span> <span class="hlt">propagation</span> in a cold magnetized dusty plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sarkar, S.; Ghosh, S.; Khan, M.</p> <p>1998-12-01</p> <p>In this paper several characteristics of low frequency <span class="hlt">waves</span> in a cold magnetized dusty plasma <span class="hlt">propagating</span> parallel and perpendicular to the static background magnetic field have been investigated. In the case of parallel <span class="hlt">propagation</span> the negatively charged dust particles resonate with the right circularly polarized (RCP) component of em <span class="hlt">waves</span> when the <span class="hlt">wave</span> frequency equals the dust cyclotron frequency. It has been shown that an RCP <span class="hlt">wave</span> in dusty plasma consists of two branches and there exists a region where an RCP <span class="hlt">wave</span> <span class="hlt">propagation</span> is not possible. Dispersion relation, phase velocity and group velocity of RCP <span class="hlt">waves</span> have been obtained and <span class="hlt">propagation</span> characteristics have been shown graphically. Poynting flux and Faraday rotation angles have been calculated for both lower and upper branches of the RCP <span class="hlt">wave</span>. It has been observed that sense of rotation of the plane of polarization of the RCP <span class="hlt">wave</span> corresponding to two distinct branches are opposite. Finally, the effect of dust particles on the induced magnetization from the inverse Faraday effect (IFE) due to the interaction of low frequency <span class="hlt">propagating</span> and standing em <span class="hlt">waves</span> with dusty plasmas has been evaluated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70030808','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70030808"><span>Case study: Mapping <span class="hlt">tsunami</span> hazards associated with debris flow into a reservoir</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Walder, J.S.; Watts, P.; Waythomas, C.F.</p> <p>2006-01-01</p> <p>Debris-flow generated impulse <span class="hlt">waves</span> (<span class="hlt">tsunamis</span>) pose hazards in lakes, especially those used for hydropower or recreation. We describe a method for assessing <span class="hlt">tsunami</span>-related hazards for the case in which inundation by coherent water <span class="hlt">waves</span>, rather than chaotic splashing, is of primary concern. The method involves an experimentally based initial condition (<span class="hlt">tsunami</span> source) and a Boussinesq model for <span class="hlt">tsunami</span> <span class="hlt">propagation</span> and inundation. Model results are used to create hazard maps that offer guidance for emergency planners and responders. An example application explores <span class="hlt">tsunami</span> hazards associated with potential debris flows entering Baker Lake, a reservoir on the flanks of the Mount Baker volcano in the northwestern United States. ?? 2006 ASCE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130011523','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130011523"><span>On the <span class="hlt">Propagation</span> and Interaction of Spherical Blast <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kandula, Max; Freeman, Robert</p> <p>2007-01-01</p> <p>The characteristics and the scaling laws of isolated spherical blast <span class="hlt">waves</span> have been briefly reviewed. Both self-similar solutions and numerical solutions of isolated blast <span class="hlt">waves</span> are discussed. Blast profiles in the near-field (strong shock region) and the far-field (weak shock region) are examined. Particular attention is directed at the blast overpressure and shock <span class="hlt">propagating</span> speed. Consideration is also given to the interaction of spherical blast <span class="hlt">waves</span>. Test data for the <span class="hlt">propagation</span> and interaction of spherical blast <span class="hlt">waves</span> emanating from explosives placed in the vicinity of a solid propellant stack are presented. These data are discussed with regard to the scaling laws concerning the decay of blast overpressure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Lambda&pg=2&id=EJ977823','ERIC'); return false;" href="https://eric.ed.gov/?q=Lambda&pg=2&id=EJ977823"><span>Teaching <span class="hlt">Wave</span> <span class="hlt">Propagation</span> and the Emergence of Viete's Formula</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Cullerne, J. P.; Goekjian, M. C. Dunn</p> <p>2012-01-01</p> <p>The well-known result for the frequency of a simple spring-mass system may be combined with elementary concepts like speed = wavelength x frequency to obtain <span class="hlt">wave</span> <span class="hlt">propagation</span> speeds for an infinite chain of springs and masses (masses "m" held apart at equilibrium distance "a" by springs of stiffness "gamma"). These <span class="hlt">propagation</span> speeds are dependent…</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EPJWC.14002023S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EPJWC.14002023S"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> of spectral energy content in a granular chain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shrivastava, Rohit Kumar; Luding, Stefan</p> <p>2017-06-01</p> <p>A mechanical <span class="hlt">wave</span> is <span class="hlt">propagation</span> of vibration with transfer of energy and momentum. Understanding the spectral energy characteristics of a <span class="hlt">propagating</span> <span class="hlt">wave</span> through disordered granular media can assist in understanding the overall properties of <span class="hlt">wave</span> <span class="hlt">propagation</span> through inhomogeneous materials like soil. The study of these properties is aimed at modeling <span class="hlt">wave</span> <span class="hlt">propagation</span> for oil, mineral or gas exploration (seismic prospecting) or non-destructive testing of the internal structure of solids. The focus is on the total energy content of a pulse <span class="hlt">propagating</span> through an idealized one-dimensional discrete particle system like a mass disordered granular chain, which allows understanding the energy attenuation due to disorder since it isolates the longitudinal P-<span class="hlt">wave</span> from shear or rotational modes. It is observed from the signal that stronger disorder leads to faster attenuation of the signal. An ordered granular chain exhibits ballistic <span class="hlt">propagation</span> of energy whereas, a disordered granular chain exhibits more diffusive like <span class="hlt">propagation</span>, which eventually becomes localized at long time periods. For obtaining mean-field macroscopic/continuum properties, ensemble averaging has been used, however, such an ensemble averaged spectral energy response does not resolve multiple scattering, leading to loss of information, indicating the need for a different framework for micro-macro averaging.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3677718','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3677718"><span>Shear <span class="hlt">wave</span> <span class="hlt">propagation</span> in anisotropic soft tissues and gels</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Namani, Ravi; Bayly, Philip V.</p> <p>2013-01-01</p> <p>The <span class="hlt">propagation</span> of shear <span class="hlt">waves</span> in soft tissue can be visualized by magnetic resonance elastography (MRE) [1] to characterize tissue mechanical properties. Dynamic deformation of brain tissue arising from shear <span class="hlt">wave</span> <span class="hlt">propagation</span> may underlie the pathology of blast-induced traumatic brain injury. White matter in the brain, like other biological materials, exhibits a transversely isotropic structure, due to the arrangement of parallel fibers. Appropriate mathematical models and well-characterized experimental systems are needed to understand <span class="hlt">wave</span> <span class="hlt">propagation</span> in these structures. In this paper we review the theory behind <span class="hlt">waves</span> in anisotropic, soft materials, including small-amplitude <span class="hlt">waves</span> superimposed on finite deformation of a nonlinear hyperelastic material. Some predictions of this theory are confirmed in experimental studies of a soft material with controlled anisotropy: magnetically-aligned fibrin gel. PMID:19963987</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840024048','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840024048"><span>Time dependent <span class="hlt">wave</span> envelope finite difference analysis of sound <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Baumeister, K. J.</p> <p>1984-01-01</p> <p>A transient finite difference <span class="hlt">wave</span> envelope formulation is presented for sound <span class="hlt">propagation</span>, without steady flow. Before the finite difference equations are formulated, the governing <span class="hlt">wave</span> equation is first transformed to a form whose solution tends not to oscillate along the <span class="hlt">propagation</span> direction. This transformation reduces the required number of grid points by an order of magnitude. Physically, the transformed pressure represents the amplitude of the conventional sound <span class="hlt">wave</span>. The derivation for the <span class="hlt">wave</span> envelope transient <span class="hlt">wave</span> equation and appropriate boundary conditions are presented as well as the difference equations and stability requirements. To illustrate the method, example solutions are presented for sound <span class="hlt">propagation</span> in a straight hard wall duct and in a two dimensional straight soft wall duct. The numerical results are in good agreement with exact analytical results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22590580-all-electrical-propagating-spin-wave-spectroscopy-broadband-wavevector-capability','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22590580-all-electrical-propagating-spin-wave-spectroscopy-broadband-wavevector-capability"><span>All electrical <span class="hlt">propagating</span> spin <span class="hlt">wave</span> spectroscopy with broadband wavevector capability</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ciubotaru, F., E-mail: Florin.Ciubotaru@imec.be; KU Leuven, Departement Electrotechniek; Devolder, T.</p> <p>2016-07-04</p> <p>We developed an all electrical experiment to perform the broadband phase-resolved spectroscopy of <span class="hlt">propagating</span> spin <span class="hlt">waves</span> in micrometer sized thin magnetic stripes. The magnetostatic surface spin <span class="hlt">waves</span> are excited and detected by scaled down to 125 nm wide inductive antennas, which award ultra broadband wavevector capability. The wavevector selection can be done by applying an excitation frequency above the ferromagnetic resonance. Wavevector demultiplexing is done at the spin <span class="hlt">wave</span> detector thanks to the rotation of the spin <span class="hlt">wave</span> phase upon <span class="hlt">propagation</span>. A simple model accounts for the main features of the apparatus transfer functions. Our approach opens an avenue for themore » all electrical study of wavevector-dependent spin <span class="hlt">wave</span> properties including dispersion spectra or non-reciprocal <span class="hlt">propagation</span>.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1984AJSE....9..135A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1984AJSE....9..135A"><span>A generalized invariant imbedding for <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ayoubi, I. S.; Nelson, P.</p> <p>1984-04-01</p> <p>The initial-value problems for reflection and transmission coefficients (imbeddings) obtained by Bellman and Wing are critically reviewed. It is shown in detail how the two reduce to a common form when both are valid. A simultaneous generalization of these two imbeddings is obtained. The generalized imbedding involves incidence onto an intermediate region of continuous <span class="hlt">wave</span> number, from a region of smooth <span class="hlt">wave</span> number, but with no requirement concerning the manner in which the <span class="hlt">wave</span> numbers join at the interface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA088030','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA088030"><span>Elastic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> through Multilayered Media</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1980-03-01</p> <p>Distilled ) 20 Water (Heavy,D^O) 19.8 o-Xylene 20 m-Xylene 20 p-Xylene 20 ■■■/ Wavespeed Long. Trans. Surf Density Ref. 10^ cm/sec gm/cm...7 3 Schematic of Three Layer Structure 15 4a Longitudinal <span class="hlt">Wave</span> Incident on a Water /Lucite Interface 17 4b Longitudinal <span class="hlt">Wave</span> Incident on a Lucite... Water Interface 17 5a Longitudinal <span class="hlt">Wave</span> Incident on an Aluminum/ Water Interface 18 5b Longitudinal <span class="hlt">Wave</span> Incident on a Steel/ Water Interface 18 6a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/49391','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/49391"><span>Stress <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Larch Plantation Trees-Numerical Simulation</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Fenglu Liu; Fang Jiang; Xiping Wang; Houjiang Zhang; Wenhua Yu</p> <p>2015-01-01</p> <p>In this paper, we attempted to simulate stress <span class="hlt">wave</span> <span class="hlt">propagation</span> in virtual tree trunks and construct two dimensional (2D) <span class="hlt">wave</span>-front maps in the longitudinal-radial section of the trunk. A tree trunk was modeled as an orthotropic cylinder in which wood properties along the fiber and in each of the two perpendicular directions were different. We used the COMSOL...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870045671&hterms=relationship+form&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Drelationship%2Bform','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870045671&hterms=relationship+form&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Drelationship%2Bform"><span>Relationship between directions of <span class="hlt">wave</span> and energy <span class="hlt">propagation</span> for cold plasma <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Musielak, Zdzislaw E.</p> <p>1986-01-01</p> <p>The dispersion relation for plasma <span class="hlt">waves</span> is considered in the 'cold' plasma approximation. General formulas for the dependence of the phase and group velocities on the direction of <span class="hlt">wave</span> <span class="hlt">propagation</span> with respect to the local magnetic field are obtained for a cold magnetized plasma. The principal cold plasma resonances and cut-off frequencies are defined for an arbitrary angle and are used to establish basic regimes of frequency where the cold plasma <span class="hlt">waves</span> can <span class="hlt">propagate</span> or can be evanescent. The relationship between direction of <span class="hlt">wave</span> and energy <span class="hlt">propagation</span>, for cold plasma <span class="hlt">waves</span> in hydrogen atmosphere, is presented in the form of angle diagrams (angle between group velocity and magnetic field versus angle between phase velocity and magnetic field) and polar diagrams (also referred to as 'Friedrich's diagrams') for different directions of <span class="hlt">wave</span> <span class="hlt">propagation</span>. Morphological features of the diagrams as well as some critical angles of <span class="hlt">propagation</span> are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=landslides&pg=2&id=EJ721578','ERIC'); return false;" href="https://eric.ed.gov/?q=landslides&pg=2&id=EJ721578"><span>What Causes <span class="hlt">Tsunamis</span>?</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Mogil, H. Michael</p> <p>2005-01-01</p> <p>On December 26, 2004, a disastrous <span class="hlt">tsunami</span> struck many parts of South Asia. The scope of this disaster has resulted in an outpouring of aid throughout the world and brought attention to the science of <span class="hlt">tsunamis</span>. "<span class="hlt">Tsunami</span>" means "harbor <span class="hlt">wave</span>" in Japanese, and the Japanese have a long history of <span class="hlt">tsunamis</span>. The word…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006ihy..workE..42D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006ihy..workE..42D"><span><span class="hlt">Propagation</span> and Dissipation of MHD <span class="hlt">Waves</span> in Coronal Holes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dwivedi, B. N.</p> <p>2006-11-01</p> <p>bholadwivedi@gmail.com In view of the landmark result on the solar wind outflow, starting between 5 Mm and 20 Mm above the photosphere in magnetic funnels, we investigate the <span class="hlt">propagation</span> and dissipation of MHD <span class="hlt">waves</span> in coronal holes. We underline the importance of Alfvén <span class="hlt">wave</span> dissipation in the magnetic funnels through the viscous and resistive plasma. Our results show that Alfvén <span class="hlt">waves</span> are one of the primary energy sources in the innermost part of coronal holes where the solar wind outflow starts. We also consider compressive viscosity and thermal conductivity to study the <span class="hlt">propagation</span> and dissipation of long period slow longitudinal MHD <span class="hlt">waves</span> in polar coronal holes. We discuss their likely role in the line profile narrowing, and in the energy budget for coronal holes and the solar wind. We compare the contribution of longitudinal MHD <span class="hlt">waves</span> with high frequency Alfvén <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910070861&hterms=propagation+layering&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dpropagation%2Blayering','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910070861&hterms=propagation+layering&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dpropagation%2Blayering"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in composite media and material characterization</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Datta, Subhendu K.; Shah, A. H.; Karunasena, W.</p> <p>1990-01-01</p> <p>Characteristics of <span class="hlt">wave</span> <span class="hlt">propagation</span> in an undamaged composite medium are influenced by many factors, the most important of which are: microstructure, constituent properties, interfaces, residual stress fields, and ply lay-ups. Measurements of <span class="hlt">wave</span> velocities, attenuation, and dispersion provide a powerful tool for nondestructive evaluation of these properties. Recent developments are reviewed for modeling ultrasonic <span class="hlt">wave</span> <span class="hlt">propagation</span> in fiber and particle-reinforced composite media. Additionally, some modeling studies are reviewed for the effects of interfaces and layering on attenuation and dispersion. These studies indicate possible ways of characterizing material properties by ultrasonic means.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995ApOpt..34.2089C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995ApOpt..34.2089C"><span>Simulation of <span class="hlt">wave</span> <span class="hlt">propagation</span> in three-dimensional random media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Coles, Wm. A.; Filice, J. P.; Frehlich, R. G.; Yadlowsky, M.</p> <p>1995-04-01</p> <p>Quantitative error analyses for the simulation of <span class="hlt">wave</span> <span class="hlt">propagation</span> in three-dimensional random media, when narrow angular scattering is assumed, are presented for plane-<span class="hlt">wave</span> and spherical-<span class="hlt">wave</span> geometry. This includes the errors that result from finite grid size, finite simulation dimensions, and the separation of the two-dimensional screens along the <span class="hlt">propagation</span> direction. Simple error scalings are determined for power-law spectra of the random refractive indices of the media. The effects of a finite inner scale are also considered. The spatial spectra of the intensity errors are calculated and compared with the spatial spectra of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010ASSP...19..433G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010ASSP...19..433G"><span>Statistical Detection of <span class="hlt">Propagating</span> <span class="hlt">Waves</span> in a Polar Coronal Hole</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gupta, G. R.; O'Shea, E.; Banerjee, D.; Popescu, M.; Doyle, J. G.</p> <p></p> <p><span class="hlt">Waves</span> are important in the heating of the solar corona and the acceleration of the solar wind. We have examined a long spectral time series sampling a southern coronal hole, observed on the 25 February 1997 using the SUMER spectrometer onboard SoHO. The observations used the spectra lines NIV 765Å, formed in the transition region, and Ne VIII 770Å, formed in the low corona. The spectra indicate the presence of compressional <span class="hlt">waves</span> with periods of about 18 min, and also significant power at shorter periods. Using Fourier techniques, we measured the phase delays between the intensity as well as the velocity oscillations in the two lines as a function of frequency. From these measurements we derive the travel time of the <span class="hlt">propagating</span> oscillations and so the <span class="hlt">propagation</span> speeds of the <span class="hlt">waves</span> producing the oscillations. As the measured <span class="hlt">propagation</span> speeds are subsonic, we conclude that the observed <span class="hlt">waves</span> are slow magneto-acoustic ones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70156824','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70156824"><span>Earthquake mechanism and seafloor deformation for <span class="hlt">tsunami</span> generation</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, Eric L.; Oglesby, David D.; Beer, Michael; Kougioumtzoglou, Ioannis A.; Patelli, Edoardo; Siu-Kui Au, Ivan</p> <p>2014-01-01</p> <p><span class="hlt">Tsunamis</span> are generated in the ocean by rapidly displacing the entire water column over a significant area. The potential energy resulting from this disturbance is balanced with the kinetic energy of the <span class="hlt">waves</span> during <span class="hlt">propagation</span>. Only a handful of submarine geologic phenomena can generate <span class="hlt">tsunamis</span>: large-magnitude earthquakes, large landslides, and volcanic processes. Asteroid and subaerial landslide impacts can generate <span class="hlt">tsunami</span> <span class="hlt">waves</span> from above the water. Earthquakes are by far the most common generator of <span class="hlt">tsunamis</span>. Generally, earthquakes greater than magnitude (M) 6.5–7 can generate <span class="hlt">tsunamis</span> if they occur beneath an ocean and if they result in predominantly vertical displacement. One of the greatest uncertainties in both deterministic and probabilistic hazard assessments of <span class="hlt">tsunamis</span> is computing seafloor deformation for earthquakes of a given magnitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.9727M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.9727M"><span>How can coastal parks contain the destructive impact of a <span class="hlt">tsunami</span>? A numerical approach to the understanding of <span class="hlt">tsunami</span>-triggered <span class="hlt">waves</span> in the presence of coastal hills</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marras, Simone; Suckale, Jenny; Lunghino, Brent; Giraldo, Francis X.; Constantinescu, Emil</p> <p>2016-04-01</p> <p>From the now common idea that vegetated shores may reduce the power of a destructive storm surge, an increasing number of coastal communities around the world are extending this thinking to the design of coastal parks as a way to limit the impact of a <span class="hlt">tsunami</span>. <span class="hlt">Tsunamis</span> and storm surges are significantly different in nature and behavior, and it is implausible that vegetation alone could act as a <span class="hlt">tsunami</span> mitigation tool. A more comprehensive approach relies on the installation of vegetated, scattered mitigation hills in front of the shore to deviate the incoming <span class="hlt">tsunami</span> <span class="hlt">wave</span> instead. The analysis of how natural obstacles affect non-linear <span class="hlt">tsunami</span> <span class="hlt">waves</span> is still very limited and consists mostly of one-dimensional studies (e.g., [1, 2]). To that end, this work aims to extend the analysis of the interaction of <span class="hlt">waves</span> of different shapes (solitary <span class="hlt">wave</span>, N-<span class="hlt">wave</span>), sizes (amplitude and <span class="hlt">wave</span> length), and configurations with large obstacles to two-dimensional flows. The following metrics are used for a quantification of the results: 1) <span class="hlt">tsunami</span> run-up and run-down and 2) a measure of channelization (via the flow kinetic energy and discharge). First, preliminary results show that the configuration of the obstacles is consequential as long as the amplitude of the incoming <span class="hlt">wave</span> is large enough relative to the obstacles. In second instance, we also observed that the channelization of the flow between two neighboring obstacles may not be greatly affected solely by the distance between obstacles, but must be analyzed in relationship to the initial <span class="hlt">wave/wave</span> train. This study is based on the numerical solution of the viscous shallow water equations via high order discontinuous finite elements method (DG) using a quadrilateral version of the model described in [3] and with fully implicit time integration [4]. Large and relatively massive hills appear to be a better solution than any offshore concrete walls, which have shown to possibly enhance the <span class="hlt">tsunami</span> catastrophic power rather than</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNH53A..04W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNH53A..04W"><span><span class="hlt">Tsunami</span> Speed Variations in Density-stratified Compressible Global Oceans</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Watada, S.</p> <p>2013-12-01</p> <p>Recent <span class="hlt">tsunami</span> observations in the deep ocean have accumulated unequivocal evidence that <span class="hlt">tsunami</span> traveltime delays compared with the linear long-<span class="hlt">wave</span> <span class="hlt">tsunami</span> simulations occur during <span class="hlt">tsunami</span> <span class="hlt">propagation</span> in the deep ocean. The delay is up to 2% of the <span class="hlt">tsunami</span> traveltime. Watada et al. [2013] investigated the cause of the delay using the normal mode theory of <span class="hlt">tsunamis</span> and attributed the delay to the compressibility of seawater, the elasticity of the solid earth, and the gravitational potential change associated with mass motion during the passage of <span class="hlt">tsunamis</span>. <span class="hlt">Tsunami</span> speed variations in the deep ocean caused by seawater density stratification is investigated using a newly developed <span class="hlt">propagator</span> matrix method that is applicable to seawater with depth-variable sound speeds and density gradients. For a 4-km deep ocean, the total <span class="hlt">tsunami</span> speed reduction is 0.45% compared with incompressible homogeneous seawater; two thirds of the reduction is due to elastic energy stored in the water and one third is due to water density stratification mainly by hydrostatic compression. <span class="hlt">Tsunami</span> speeds are computed for global ocean density and sound speed profiles and characteristic structures are discussed. <span class="hlt">Tsunami</span> speed reductions are proportional to ocean depth with small variations, except for in warm Mediterranean seas. The impacts of seawater compressibility and the elasticity effect of the solid earth on <span class="hlt">tsunami</span> traveltime should be included for precise modeling of trans-oceanic <span class="hlt">tsunamis</span>. Data locations where a vertical ocean profile deeper than 2500 m is available in World Ocean Atlas 2009. The dark gray area indicates the Pacific Ocean defined in WOA09. a) <span class="hlt">Tsunami</span> speed variations. Red, gray and black bars represent global, Pacific, and Mediterranean Sea, respectively. b) Regression lines of the <span class="hlt">tsunami</span> velocity reduction for all oceans. c)Vertical ocean profiles at grid points indicated by the stars in Figure 1.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH41A1742K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH41A1742K"><span><span class="hlt">Tsunami</span> Focusing and Leading Amplitude</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kanoglu, U.</p> <p>2016-12-01</p> <p><span class="hlt">Tsunamis</span> transform substantially through spatial and temporal spreading from their source region. This substantial spreading might result unique maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights which might be attributed to the source configuration, directivity, the waveguide structures of mid-ocean ridges and continental shelves, focusing and defocusing through submarine seamounts, random focusing due to small changes in bathymetry, dispersion, and, most likely, combination of some of these effects. In terms of the maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> height, after Okal and Synolakis (2016 Geophys. J. Int. 204, 719-735), it is clear that dispersion would be one of the reasons to drive the leading <span class="hlt">wave</span> amplitude in a <span class="hlt">tsunami</span> <span class="hlt">wave</span> train. Okal and Synolakis (2016), referring to this phenomenon as sequencing -later <span class="hlt">waves</span> in the train becoming higher than the leading one, considered Hammack's (1972, Ph.D. Dissertation, Calif. Inst. Tech., 261 pp) formalism, in addition to LeMéhauté and Wang's (1995 Water <span class="hlt">waves</span> generated by underwater explosion, World Scientific, 367 pp), to evaluate linear dispersive <span class="hlt">tsunami</span> <span class="hlt">propagation</span> from a circular plug uplifted on an ocean of constant depth. They identified transition distance, as the second <span class="hlt">wave</span> being larger, performing parametric study for the radius of the plug and the depth of the ocean. Here, we extend Okal and Synolakis' (2016) analysis to an initial <span class="hlt">wave</span> field with a finite crest length and, in addition, to a most common <span class="hlt">tsunami</span> initial <span class="hlt">wave</span> form of N-<span class="hlt">wave</span> (Tadepalli and Synolakis, 1994 Proc. R. Soc. A: Math. Phys. Eng. Sci. 445, 99-112). First, we investigate the focusing feature in the leading-depression side, which enhance <span class="hlt">tsunami</span> <span class="hlt">wave</span> height as presented by Kanoglu et al. (2013 Proc. R. Soc. A: Math. Phys. Eng. Sci. 469, 20130015). We then discuss the results in terms of leading <span class="hlt">wave</span> amplitude presenting a parametric study and identify a simple relation for the transition distance. The solution presented here could be used to better analyze dispersive</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=tornado&pg=2&id=EJ965714','ERIC'); return false;" href="https://eric.ed.gov/?q=tornado&pg=2&id=EJ965714"><span><span class="hlt">Waves</span> of Change: Lessons from the <span class="hlt">Tsunami</span> Disaster</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Hernandez, Luis A.</p> <p>2011-01-01</p> <p>Many are fortunate never to have experienced the abrupt and devastating change a natural disaster can deliver, whether it be an earthquake, a tornado, or a wildfire. But one does experience similar hurt, pain, and loss in the <span class="hlt">waves</span> of change that affect one's personal life. In a New York Times article on March 24, 2011, Martin Fackler describes…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018NPGeo..25..301V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018NPGeo..25..301V"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in the Lorenz-96 model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>van Kekem, Dirk L.; Sterk, Alef E.</p> <p>2018-04-01</p> <p>In this paper we study the spatiotemporal properties of <span class="hlt">waves</span> in the Lorenz-96 model and their dependence on the dimension parameter n and the forcing parameter F. For F > 0 the first bifurcation is either a supercritical Hopf or a double-Hopf bifurcation and the periodic attractor born at these bifurcations represents a traveling <span class="hlt">wave</span>. Its spatial <span class="hlt">wave</span> number increases linearly with n, but its period tends to a finite limit as n → ∞. For F < 0 and odd n, the first bifurcation is again a supercritical Hopf bifurcation, but in this case the period of the traveling <span class="hlt">wave</span> also grows linearly with n. For F < 0 and even n, however, a Hopf bifurcation is preceded by either one or two pitchfork bifurcations, where the number of the latter bifurcations depends on whether n has remainder 2 or 0 upon division by 4. This bifurcation sequence leads to stationary <span class="hlt">waves</span> and their spatiotemporal properties also depend on the remainder after dividing n by 4. Finally, we explain how the double-Hopf bifurcation can generate two or more stable <span class="hlt">waves</span> with different spatiotemporal properties that coexist for the same parameter values n and F.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFM.U53C..06H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFM.U53C..06H"><span>Estimating Seismic Moment From Broadband P-<span class="hlt">Waves</span> for <span class="hlt">Tsunami</span> Warnings.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hirshorn, B. F.</p> <p>2006-12-01</p> <p>The Richard H. Hagemeyer Pacific <span class="hlt">Tsunami</span> Warning Center (PTWC), located in Ewa Beach, Oahu, Hawaii, is responsible for issuing local, regional, and distant <span class="hlt">tsunami</span> warnings to Hawaii, and for issuing regional and distant <span class="hlt">tsunami</span> warnings to the rest of the Pacific Basin, exclusive of the US West Coast. The PTWC must provide these <span class="hlt">tsunami</span> warnings as soon as technologically possible, based entirely on estimates of a potentially tsunamigenic earthquake's source parameters. We calculate the broadband P-<span class="hlt">wave</span> moment magnitude, Mwp, from the P or pP <span class="hlt">wave</span> velocity seismograms [Tsuboi et al., 1995, 1999]. This method appears to work well for regional and teleseismic events [ Tsuboi et al (1999], Whitmore et al (2002), Hirshorn et al (2004) ]. Following Tsuboi, [1995], we consider the displacement record of the P-<span class="hlt">wave</span> portion of the broadband seismograms as an approximate source time function and integrate this record to obtain the moment rate function, Mo(t), and the moment magnitude [Hanks and Kanamori, 1972] as a function of time, Mw(t). We present results for Mwp for local, regional, and teleseismic broad band recordings for earthquakes in the Mw 5 to 9.3 range. As large Hawaii events are rare, we tested this local case using other Pacific events in the magnitude 5.0 to 7.5 range recorded by nearby stations. Signals were excluded, however, if the epicentral distance was so small (generally less than 1 degree) that there was contamination by the S-<span class="hlt">wave</span> too closely following the P-<span class="hlt">waves</span>. Scatter plots of Mwp against the Harvard Mw for these events shows that Mwp does predict Mw well from seismograms recorded at local, regional, and teleseismic distances. For some complex earthquakes, eg. the Mw 8.4(HRV) Peru earthquake of June 21, 2001, Mwp underestimates Mw if the first moment release is not the largest. Our estimates of Mwp for the Mw 9.3 Summatra-Andaman Island's earthquake of December 26, 2004 and for the Mw 8.7 (HRV) Summatra event of March 28, 2005, were Mwp 8</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011GeoJI.187.1699O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011GeoJI.187.1699O"><span>An irregular lattice method for elastic <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>O'Brien, Gareth S.; Bean, Christopher J.</p> <p>2011-12-01</p> <p>Lattice methods are a class of numerical scheme which represent a medium as a connection of interacting nodes or particles. In the case of modelling seismic <span class="hlt">wave</span> <span class="hlt">propagation</span>, the interaction term is determined from Hooke's Law including a bond-bending term. This approach has been shown to model isotropic seismic <span class="hlt">wave</span> <span class="hlt">propagation</span> in an elastic or viscoelastic medium by selecting the appropriate underlying lattice structure. To predetermine the material constants, this methodology has been restricted to regular grids, hexagonal or square in 2-D or cubic in 3-D. Here, we present a method for isotropic elastic <span class="hlt">wave</span> <span class="hlt">propagation</span> where we can remove this lattice restriction. The methodology is outlined and a relationship between the elastic material properties and an irregular lattice geometry are derived. The numerical method is compared with an analytical solution for <span class="hlt">wave</span> <span class="hlt">propagation</span> in an infinite homogeneous body along with comparing the method with a numerical solution for a layered elastic medium. The dispersion properties of this method are derived from a plane <span class="hlt">wave</span> analysis showing the scheme is more dispersive than a regular lattice method. Therefore, the computational costs of using an irregular lattice are higher. However, by removing the regular lattice structure the anisotropic nature of fracture <span class="hlt">propagation</span> in such methods can be removed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770004172','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770004172"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in fiber composite laminates, part 2</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Daniel, I. M.; Liber, T.</p> <p>1976-01-01</p> <p>An experimental investigation was conducted to determine the <span class="hlt">wave</span> <span class="hlt">propagation</span> characteristics, transient strains and residual properties in unidirectional and angle-ply boron/epoxy and graphite/epoxy laminates impacted with silicone rubber projectiles at velocities up to 250 MS-1. The predominant <span class="hlt">wave</span> is flexural, <span class="hlt">propagating</span> at different velocities in different directions. In general, measured <span class="hlt">wave</span> velocities were higher than theoretically predicted values. The amplitude of the in-plane <span class="hlt">wave</span> is less than ten percent of that of the flexural <span class="hlt">wave</span>. Peak strains and strain rates in the transverse to the (outer) fiber direction are much higher than those in the direction of the fibers. The dynamics of impact were also studied with high speed photography.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IzAOP..51..557B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IzAOP..51..557B"><span><span class="hlt">Propagation</span> of inertial-gravity <span class="hlt">waves</span> on an island shelf</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bondur, V. G.; Sabinin, K. D.; Grebenyuk, Yu. V.</p> <p>2015-09-01</p> <p>The <span class="hlt">propagation</span> of inertial-gravity <span class="hlt">waves</span> (IGV) at the boundary of the Pacific shelf near the island of Oahu (Hawaii), whose generation was studied in the first part of this work [1], is analyzed. It is shown that a significant role there is played by the plane oblique <span class="hlt">waves</span>; whose characteristics were identified by the method of estimating 3D <span class="hlt">wave</span> parameters for the cases when the measurements are available only for two verticals. It is established that along with the descending <span class="hlt">propagation</span> of energy that is typical of IGVs, <span class="hlt">wave</span> packets ascend from the bottom to the upper layers, which is caused by the emission of <span class="hlt">waves</span> from intense jets of discharged waters flowing out of a diffusor located at the bottom.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9674E..0LT','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9674E..0LT"><span>A <span class="hlt">propagation</span> method with adaptive mesh grid based on <span class="hlt">wave</span> characteristics for <span class="hlt">wave</span> optics simulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tang, Qiuyan; Wang, Jing; Lv, Pin; Sun, Quan</p> <p>2015-10-01</p> <p><span class="hlt">Propagation</span> simulation method and choosing mesh grid are both very important to get the correct <span class="hlt">propagation</span> results in <span class="hlt">wave</span> optics simulation. A new angular spectrum <span class="hlt">propagation</span> method with alterable mesh grid based on the traditional angular spectrum method and the direct FFT method is introduced. With this method, the sampling space after <span class="hlt">propagation</span> is not limited to <span class="hlt">propagation</span> methods no more, but freely alterable. However, choosing mesh grid on target board influences the validity of simulation results directly. So an adaptive mesh choosing method based on <span class="hlt">wave</span> characteristics is proposed with the introduced <span class="hlt">propagation</span> method. We can calculate appropriate mesh grids on target board to get satisfying results. And for complex initial <span class="hlt">wave</span> field or <span class="hlt">propagation</span> through inhomogeneous media, we can also calculate and set the mesh grid rationally according to above method. Finally, though comparing with theoretical results, it's shown that the simulation result with the proposed method coinciding with theory. And by comparing with the traditional angular spectrum method and the direct FFT method, it's known that the proposed method is able to adapt to a wider range of Fresnel number conditions. That is to say, the method can simulate <span class="hlt">propagation</span> results efficiently and correctly with <span class="hlt">propagation</span> distance of almost zero to infinity. So it can provide better support for more <span class="hlt">wave</span> <span class="hlt">propagation</span> applications such as atmospheric optics, laser <span class="hlt">propagation</span> and so on.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.9483V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.9483V"><span>Generation and Upper Atmospheric <span class="hlt">Propagation</span> of Acoustic Gravity <span class="hlt">Waves</span> according to Numerical Modeling and Radio Tomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vorontsov, Artem; Andreeva, Elena; Nesterov, Ivan; Padokhin, Artem; Kurbatov, Grigory</p> <p>2016-04-01</p> <p>The acoustic-gravity <span class="hlt">waves</span> (AGW) in the upper atmosphere and ionosphere can be generated by a variety of the phenomena in the near-Earth environment and atmosphere as well as by some perturbations of the Earth's ground or ocean surface. For instance, the role of the AGW sources can be played by the earthquakes, explosions, thermal heating, seisches, <span class="hlt">tsunami</span> <span class="hlt">waves</span>. We present the examples of AGWs excited by the <span class="hlt">tsunami</span> <span class="hlt">waves</span> traveling in the ocean, by seisches, and by ionospheric heating by the high-power radio <span class="hlt">wave</span>. In the last case, the gravity <span class="hlt">waves</span> are caused by the pulsed modulation of the heating <span class="hlt">wave</span>. The AGW <span class="hlt">propagation</span> in the upper atmosphere induces the variations and irregularities in the electron density distribution of the ionosphere, whose structure can be efficiently reconstructed by the method of the ionospheric radio tomography (RT) based on the data from the global navigational satellite systems (GNSS). The input data for RT diagnostics are composed of the 150/400 MHz radio signals from the low-orbiting (LO) satellites and 1.2-1.5 GHz radio signals from the high-orbiting (HO) satellites with their orbits at ~1000 and ~20000 km above the ground, respectively. These data enable ionospheric imaging on different spatiotemporal scales with different spatiotemporal resolution and coverage, which is suitable, inter alia, for tracking the <span class="hlt">waves</span> and <span class="hlt">wave</span>-like features in the ionosphere. In particular, we demonstrate the maps of the ionospheric responses to the tornado at Moore (Oklahoma, USA) of May 20, 2013, which are reconstructed from the HO data. We present the examples of LORT images containing the <span class="hlt">waves</span> and wavelike disturbances associated with various sources (e.g., auroral precipitation and high-power heating of the ionosphere). We also discuss the results of modeling the AGW generation by the surface and volumetric sources. The millihertz AGW from these sources initiate the ionospheric perturbation with a typical scale of a few hundred km at the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUSM.H53B..01F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUSM.H53B..01F"><span>Peru 2007 <span class="hlt">tsunami</span> runup observations and modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fritz, H. M.; Kalligeris, N.; Borrero, J. C.</p> <p>2008-05-01</p> <p>On 15 August 2007 an earthquake with moment magnitude (Mw) of 8.0 centered off the coast of central Peru, generated a <span class="hlt">tsunami</span> with locally focused runup heights of up to 10 m. A reconnaissance team was deployed in the immediate aftermath and investigated the <span class="hlt">tsunami</span> effects at 51 sites. The largest runup heights were measured in a sparsely populated desert area south of the Paracas Peninsula resulting in only 3 <span class="hlt">tsunami</span> fatalities. Numerical modeling of the earthquake source and <span class="hlt">tsunami</span> suggest that a region of high slip near the coastline was primarily responsible for the extreme runup heights. The town of Pisco was spared by the presence of the Paracas Peninsula, which blocked <span class="hlt">tsunami</span> <span class="hlt">waves</span> from <span class="hlt">propagating</span> northward from the high slip region. The coast of Peru has experienced numerous deadly and destructive <span class="hlt">tsunamis</span> throughout history, which highlights the importance of ongoing <span class="hlt">tsunami</span> awareness and education efforts in the region. The Peru <span class="hlt">tsunami</span> is compared against recent mega-disasters such as the 2004 Indian Ocean <span class="hlt">tsunami</span> and Hurricane Katrina.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JSV...406...89L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JSV...406...89L"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> characteristics of a magnetic granular chain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leng, Dingxin; Liu, Guijie; Sun, Lingyu; Wang, Xiaojie</p> <p>2017-10-01</p> <p>We investigate the <span class="hlt">wave</span> <span class="hlt">propagation</span> characteristics of a horizontal alignment of magnetic grains under a non-uniform magnetic field. The magnetic force of each grain is obtained using Maxwell's principle. The contact interaction of grains is based on Hertz potential. The effects of magnetic field strength on the dynamic responses of a granular chain under strong, intermediate, and weak amplitudes of incident impulses in comparison with static precompression force are studied. Different <span class="hlt">wave</span> <span class="hlt">propagation</span> modes induced by the magnetic field are observed. The applied field strength demonstrably reinforces the granular-position-dependent behaviors of decreasing amplitude and increasing <span class="hlt">wave</span> <span class="hlt">propagation</span> velocity. The magnetic field-induced features of a magnetic granular chain have potential applications in adaptive structures for shock attenuation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870064791&hterms=projectile+motion&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dprojectile%2Bmotion','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870064791&hterms=projectile+motion&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dprojectile%2Bmotion"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in a plate after impact by a projectile</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>El-Raheb, M.; Wagner, P.</p> <p>1987-01-01</p> <p>The <span class="hlt">wave</span> <span class="hlt">propagation</span> in a circular plate after impact by a cylindrical projectile is studied. In the vicinity of impact, the pressure is computed numerically. An intense pressure pulse is generated that peaks 0.2 microns after impact, then drops sharply to a plateau. The response of the plate is determined adopting a modal solution of Mindlin's equations. Velocity and acceleration histories display both <span class="hlt">propagating</span> and dispersive features.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018CMT...tmp...46Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018CMT...tmp...46Z"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> model of heat conduction and group speed</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Long; Zhang, Xiaomin; Peng, Song</p> <p>2018-03-01</p> <p>In view of the finite relaxation model of non-Fourier's law, the Cattaneo and Vernotte (CV) model and Fourier's law are presented in this work for comparing <span class="hlt">wave</span> <span class="hlt">propagation</span> modes. Independent variable translation is applied to solve the partial differential equation. Results show that the general form of the time spatial distribution of temperature for the three media comprises two solutions: those corresponding to the positive and negative logarithmic heating rates. The former shows that a group of heat <span class="hlt">waves</span> whose spatial distribution follows the exponential function law <span class="hlt">propagates</span> at a group speed; the speed of <span class="hlt">propagation</span> is related to the logarithmic heating rate. The total speed of all the possible heat <span class="hlt">waves</span> can be combined to form the group speed of the <span class="hlt">wave</span> <span class="hlt">propagation</span>. The latter indicates that the spatial distribution of temperature, which follows the exponential function law, decays with time. These features show that <span class="hlt">propagation</span> accelerates when heated and decelerates when cooled. For the model media that follow Fourier's law and correspond to the positive heat rate of heat conduction, the <span class="hlt">propagation</span> mode is also considered the <span class="hlt">propagation</span> of a group of heat <span class="hlt">waves</span> because the group speed has no upper bound. For the finite relaxation model with non-Fourier media, the interval of group speed is bounded and the maximum speed can be obtained when the logarithmic heating rate is exactly the reciprocal of relaxation time. And for the CV model with a non-Fourier medium, the interval of group speed is also bounded and the maximum value can be obtained when the logarithmic heating rate is infinite.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018CRPhy..19...26P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018CRPhy..19...26P"><span>DEMETER observations of manmade <span class="hlt">waves</span> that <span class="hlt">propagate</span> in the ionosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parrot, Michel</p> <p>2018-01-01</p> <p>This paper is a review of manmade <span class="hlt">waves</span> observed by the ionospheric satellite DEMETER. It concerns <span class="hlt">waves</span> emitted by the ground-based VLF and ELF transmitters, by broadcasting stations, by the power line harmonic radiation, by industrial noise, and by active experiments. Examples are shown including, for the first time, the record of a <span class="hlt">wave</span> coming from an ELF transmitter. These <span class="hlt">waves</span> <span class="hlt">propagate</span> upwards in the magnetosphere and they can be observed in the magnetically conjugated region of emission. Depending on their frequencies, they perturb the ionosphere and the particles in the radiation belts, and additional emissions are triggered. xml:lang="fr"</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9671E..18Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9671E..18Z"><span>Numeric analysis of terahertz <span class="hlt">wave</span> <span class="hlt">propagation</span> in familiar packaging materials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Lihong; Yang, Guang</p> <p>2015-10-01</p> <p>To assess the potential application of terahertz <span class="hlt">waves</span> in security examination, the transmission characteristics of terahertz <span class="hlt">waves</span> in packaging materials should be studied. This paper simulates the <span class="hlt">propagation</span> of terahertz <span class="hlt">waves</span> in cloth and paper, studies the changes of shape and position of crest of terahertz <span class="hlt">waves</span> before and after these materials, and gets the law of these changes, which has potential applications in thickness measurement for the thin insulated materials; gives reflected and transmitted <span class="hlt">wave</span> of terahertz <span class="hlt">waves</span>, and computes reflected and transmitted coefficient, indicates the good transmission properties of these materials for terahertz <span class="hlt">waves</span>, which provides the theoretical basis for the realization of contactless security examination of packaged post, package and people pass the important passageway (such as airport and station).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/7199622-nonlinear-wave-equation-nonadiabatic-flame-propagation','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/7199622-nonlinear-wave-equation-nonadiabatic-flame-propagation"><span>A nonlinear <span class="hlt">wave</span> equation in nonadiabatic flame <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Booty, M.R.; Matalon, M.; Matkowsky, B.J.</p> <p>1988-06-01</p> <p>The authors derive a nonlinear <span class="hlt">wave</span> equation from the diffusional thermal model of gaseous combustion to describe the evolution of a flame front. The equation arises as a long <span class="hlt">wave</span> theory, for values of the volumeric heat loss in a neighborhood of the extinction point (beyond which planar uniformly <span class="hlt">propagating</span> flames cease to exist), and for Lewis numbers near the critical value beyond which uniformly <span class="hlt">propagating</span> planar flames lose stability via a degenerate Hopf bifurcation. Analysis of the equation suggests the possibility of a singularity developing in finite time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26245839','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26245839"><span>Destructive <span class="hlt">tsunami</span>-like <span class="hlt">wave</span> generated by surf beat over a coral reef during Typhoon Haiyan.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Roeber, Volker; Bricker, Jeremy D</p> <p>2015-08-06</p> <p>Storm surges cause coastal inundation due to setup of the water surface resulting from atmospheric pressure, surface winds and breaking <span class="hlt">waves</span>. Here we show that during Typhoon Haiyan, the setup generated by breaking <span class="hlt">waves</span> near the fringing-reef-protected town of Hernani, the Philippines, oscillated with the incidence of large and small <span class="hlt">wave</span> groups, and steepened into a <span class="hlt">tsunami</span>-like <span class="hlt">wave</span> that caused extensive damage and casualties. Though fringing reefs usually protect coastal communities from moderate storms, they can exacerbate flooding during strong events with energetic <span class="hlt">waves</span>. Typical for reef-type bathymetries, a very short <span class="hlt">wave</span>-breaking zone over the steep reef face facilitates the freeing of infragravity-period fluctuations (surf beat) with little energy loss. Since coastal flood planning relies on phase-averaged <span class="hlt">wave</span> modelling, infragravity surges are not being accounted for. This highlights the necessity for a policy change and the adoption of phase-resolving <span class="hlt">wave</span> models for hazard assessment in regions with fringing reefs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4918328','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4918328"><span>Destructive <span class="hlt">tsunami</span>-like <span class="hlt">wave</span> generated by surf beat over a coral reef during Typhoon Haiyan</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Roeber, Volker; Bricker, Jeremy D.</p> <p>2015-01-01</p> <p>Storm surges cause coastal inundation due to setup of the water surface resulting from atmospheric pressure, surface winds and breaking <span class="hlt">waves</span>. Here we show that during Typhoon Haiyan, the setup generated by breaking <span class="hlt">waves</span> near the fringing-reef-protected town of Hernani, the Philippines, oscillated with the incidence of large and small <span class="hlt">wave</span> groups, and steepened into a <span class="hlt">tsunami</span>-like <span class="hlt">wave</span> that caused extensive damage and casualties. Though fringing reefs usually protect coastal communities from moderate storms, they can exacerbate flooding during strong events with energetic <span class="hlt">waves</span>. Typical for reef-type bathymetries, a very short <span class="hlt">wave</span>-breaking zone over the steep reef face facilitates the freeing of infragravity-period fluctuations (surf beat) with little energy loss. Since coastal flood planning relies on phase-averaged <span class="hlt">wave</span> modelling, infragravity surges are not being accounted for. This highlights the necessity for a policy change and the adoption of phase-resolving <span class="hlt">wave</span> models for hazard assessment in regions with fringing reefs. PMID:26245839</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SPIE10170E..2BP','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SPIE10170E..2BP"><span>High frequency guided <span class="hlt">wave</span> <span class="hlt">propagation</span> in monocrystalline silicon wafers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pizzolato, Marco; Masserey, Bernard; Robyr, Jean-Luc; Fromme, Paul</p> <p>2017-04-01</p> <p>Monocrystalline silicon wafers are widely used in the photovoltaic industry for solar panels with high conversion efficiency. The cutting process can introduce micro-cracks in the thin wafers and lead to varying thickness. High frequency guided ultrasonic <span class="hlt">waves</span> are considered for the structural monitoring of the wafers. The anisotropy of the monocrystalline silicon leads to variations of the <span class="hlt">wave</span> characteristics, depending on the <span class="hlt">propagation</span> direction relative to the crystal orientation. Full three-dimensional Finite Element simulations of the guided <span class="hlt">wave</span> <span class="hlt">propagation</span> were conducted to visualize and quantify these effects for a line source. The phase velocity (slowness) and skew angle of the two fundamental Lamb <span class="hlt">wave</span> modes (first anti-symmetric mode A0 and first symmetric mode S0) for varying <span class="hlt">propagation</span> directions relative to the crystal orientation were measured experimentally. Selective mode excitation was achieved using a contact piezoelectric transducer with a custom-made wedge and holder to achieve a controlled contact pressure. The out-of-plane component of the guided <span class="hlt">wave</span> <span class="hlt">propagation</span> was measured using a noncontact laser interferometer. Good agreement was found with the simulation results and theoretical predictions based on nominal material properties of the silicon wafer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19720022244','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19720022244"><span>Holographic measurement of <span class="hlt">wave</span> <span class="hlt">propagation</span> in axi-symmetric shells</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Evensen, D. A.; Aprahamian, R.; Jacoby, J. L.</p> <p>1972-01-01</p> <p>The report deals with the use of pulsed, double-exposure holographic interferometry to record the <span class="hlt">propagation</span> of transverse <span class="hlt">waves</span> in thin-walled axi-symmetric shells. The report is subdivided into sections dealing with: (1) <span class="hlt">wave</span> <span class="hlt">propagation</span> in circular cylindrical shells, (2) <span class="hlt">wave</span> <span class="hlt">propagation</span> past cut-outs and stiffeners, and (3) <span class="hlt">wave</span> <span class="hlt">propagation</span> in conical shells. Several interferograms are presented herein which show the <span class="hlt">waves</span> reflecting from the shell boundaries, from cut-outs, and from stiffening rings. The initial response of the shell was nearly axi-symmetric in all cases, but nonsymmetric modes soon appeared in the radial response. This result suggests that the axi-symmetric response of the shell may be dynamically unstable, and thus may preferentially excite certain circumferential harmonics through parametric excitation. Attempts were made throughout to correlate the experimental data with analysis. For the most part, good agreement between theory and experiment was obtained. Occasional differences were attributed primarily to simplifying assumptions used in the analysis. From the standpoint of engineering applications, it is clear that pulsed laser holography can be used to obtain quantitative engineering data. Areas of dynamic stress concentration, stress concentration factors, local anomalies, etc., can be readily determined by holography.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH43B1863G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH43B1863G"><span>Development of new <span class="hlt">tsunami</span> detection algorithms for high frequency radars and application to <span class="hlt">tsunami</span> warning in British Columbia, Canada</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grilli, S. T.; Guérin, C. A.; Shelby, M. R.; Grilli, A. R.; Insua, T. L.; Moran, P., Jr.</p> <p>2016-12-01</p> <p>A High-Frequency (HF) radar was installed by Ocean Networks Canada in Tofino, BC, to detect <span class="hlt">tsunamis</span> from far- and near-field seismic sources; in particular, from the Cascadia Subduction Zone. This HF radar can measure ocean surface currents up to a 70-85 km range, depending on atmospheric conditions, based on the Doppler shift they cause in ocean <span class="hlt">waves</span> at the Bragg frequency. In earlier work, we showed that <span class="hlt">tsunami</span> currents must be at least 0.15 m/s to be directly detectable by a HF radar, when considering environmental noise and background currents (from tide/mesoscale circulation). This limits a direct <span class="hlt">tsunami</span> detection to shallow water areas where currents are sufficiently strong due to <span class="hlt">wave</span> shoaling and, hence, to the continental shelf. It follows that, in locations with a narrow shelf, warning times using a direct inversion method will be small. To detect <span class="hlt">tsunamis</span> in deeper water, beyond the continental shelf, we proposed a new algorithm that does not require directly inverting currents, but instead is based on observing changes in patterns of spatial correlations of the raw radar signal between two radar cells located along the same <span class="hlt">wave</span> ray, after time is shifted by the <span class="hlt">tsunami</span> <span class="hlt">propagation</span> time along the ray. A pattern change will indicate the presence of a <span class="hlt">tsunami</span>. We validated this new algorithm for idealized <span class="hlt">tsunami</span> <span class="hlt">wave</span> trains <span class="hlt">propagating</span> over a simple seafloor geometry in a direction normally incident to shore. Here, we further develop, extend, and validate the algorithm for realistic case studies of seismic <span class="hlt">tsunami</span> sources impacting Vancouver Island, BC. <span class="hlt">Tsunami</span> currents, computed with a state-of-the-art long <span class="hlt">wave</span> model are spatially averaged over cells aligned along individual <span class="hlt">wave</span> rays, located within the radar sweep area, obtained by solving the <span class="hlt">wave</span> geometric optic equation; for long <span class="hlt">waves</span>, such rays and <span class="hlt">tsunami</span> <span class="hlt">propagation</span> times along those are only function of the seafloor bathymetry, and hence can be precalculated for different incident <span class="hlt">tsunami</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3219142','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3219142"><span>Influence of coastal vegetation on the 2004 <span class="hlt">tsunami</span> <span class="hlt">wave</span> impact in west Aceh</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Laso Bayas, Juan Carlos; Marohn, Carsten; Dercon, Gerd; Dewi, Sonya; Piepho, Hans Peter; Joshi, Laxman; van Noordwijk, Meine; Cadisch, Georg</p> <p>2011-01-01</p> <p>In a <span class="hlt">tsunami</span> event human casualties and infrastructure damage are determined predominantly by seaquake intensity and offshore properties. On land, <span class="hlt">wave</span> energy is attenuated by gravitation (elevation) and friction (land cover). Tree belts have been promoted as “bioshields” against <span class="hlt">wave</span> impact. However, given the lack of quantitative evidence of their performance in such extreme events, tree belts have been criticized for creating a false sense of security. This study used 180 transects perpendicular to over 100 km on the west coast of Aceh, Indonesia to analyze the influence of coastal vegetation, particularly cultivated trees, on the impact of the 2004 <span class="hlt">tsunami</span>. Satellite imagery; land cover maps; land use characteristics; stem diameter, height, and planting density; and a literature review were used to develop a land cover roughness coefficient accounting for the resistance offered by different land uses to the <span class="hlt">wave</span> advance. Applying a spatial generalized linear mixed model, we found that while distance to coast was the dominant determinant of impact (casualties and infrastructure damage), the existing coastal vegetation in front of settlements also significantly reduced casualties by an average of 5%. In contrast, dense vegetation behind villages endangered human lives and increased structural damage. Debris carried by the backwash may have contributed to these dissimilar effects of land cover. For sustainable and effective coastal risk management, location of settlements is essential, while the protective potential of coastal vegetation, as determined by its spatial arrangement, should be regarded as an important livelihood provider rather than just as a bioshield. PMID:22065751</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADP204447','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADP204447"><span>Seismic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in South America,</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1995-08-14</p> <p>Baby, P., B. Guiller, J . Oller , G. Herail, G. Montemurro D. 371 Zubietta and M. Specht (1993). Structural synthesis of the Bolivian Subandean zone...Bueno, E., A. Chirinos, J . Pinto and J . Moreno (1993). Structural interpretation of Ceuta Field, Lake Maracaibo, Venezuela. In Andean Geodynamics...on a lithospheric model. J . Geophys. Res. 98, 9825-9844. Drake, L.A. (1989). Love and Rayleigh <span class="hlt">waves</span> in irregular structures. In Observatory</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPC.1793e0019G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPC.1793e0019G"><span>The rarefaction <span class="hlt">wave</span> <span class="hlt">propagation</span> in transparent windows</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Glam, B.; Porat, E.; Horovitz, Y.; Yosef-Hai, A.</p> <p>2017-01-01</p> <p>The radial (lateral) rarefaction <span class="hlt">wave</span> velocity of polymethyl methacrylate (PMMA) and Lithium Fluoride (LiF) windows were studied by plate impact experiments that were carried out at Soreq NRC up to a pressure of 146 kbar in the PMMA and 334 kbar in the LiF. The windows were glued to Lead targets that were impacted by a copper impactor. The VISAR measurement was done in the window interface with the target. This information was utilized to identify the radial rarefaction arrival time at the center of different diameter windows after the shock event, and served as a measurement to the radial <span class="hlt">wave</span> velocity in the shocked material. It was found that for both windows, LiF or PMMA, the measured radial <span class="hlt">wave</span> velocity increases with the pressure. Furthermore, this velocity is significantly higher compared to the expected longitudinal sound velocity at the same pressure, calculated by the Steinberg EOS in the PMMA and by ab initio calculation in the LiF. Here we present the experimental results and a comparison with analytical calculation of the sound velocity using the Steinberg EOS.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900007083','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900007083"><span>A space-time discretization procedure for <span class="hlt">wave</span> <span class="hlt">propagation</span> problems</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Davis, Sanford</p> <p>1989-01-01</p> <p>Higher order compact algorithms are developed for the numerical simulation of <span class="hlt">wave</span> <span class="hlt">propagation</span> by using the concept of a discrete dispersion relation. The dispersion relation is the imprint of any linear operator in space-time. The discrete dispersion relation is derived from the continuous dispersion relation by examining the process by which locally plane <span class="hlt">waves</span> <span class="hlt">propagate</span> through a chosen grid. The exponential structure of the discrete dispersion relation suggests an efficient splitting of convective and diffusive terms for dissipative <span class="hlt">waves</span>. Fourth- and eighth-order convection schemes are examined that involve only three or five spatial grid points. These algorithms are subject to the same restrictions that govern the use of dispersion relations in the constructions of asymptotic expansions to nonlinear evolution equations. A new eighth-order scheme is developed that is exact for Courant numbers of 1, 2, 3, and 4. Examples are given of a pulse and step <span class="hlt">wave</span> with a small amount of physical diffusion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSH51A2088T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSH51A2088T"><span>A Study of Alfven <span class="hlt">Wave</span> <span class="hlt">Propagation</span> and Heating the Chromosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tu, J.; Song, P.</p> <p>2013-12-01</p> <p>Alfven <span class="hlt">wave</span> <span class="hlt">propagation</span>, reflection and heating of the solar atmosphere are studied for a one-dimensional solar atmosphere by self-consistently solving plasma and neutral fluid equations and Maxwell's equations with incorporation of the Hall effect, strong electron-neutral, electron-ion, and ion-neutral collisions. The governing equations are very stiff because of the strong coupling between the charged and neutral fluids. We have developed a numerical model based on an implicit backward difference formula (BDF2) of second order accuracy both in time and space to overcome the stiffness. A non-reflecting boundary condition is applied to the top boundary of the simulation domain so that the <span class="hlt">wave</span> reflection within the domain due to the density gradient can be unambiguously determined. It is shown that the Alfven <span class="hlt">waves</span> are partially reflected throughout the chromosphere. The reflection is increasingly stronger at higher altitudes and the strongest reflection occurs at the transition region. The <span class="hlt">waves</span> are damped in the lower chromosphere dominantly through Joule dissipation due to electron collisions with neutrals and ions. The heating resulting from the <span class="hlt">wave</span> damping is strong enough to balance the radiation energy loss for the quiet chromosphere. The collisional dissipation of the Alfven <span class="hlt">waves</span> in the weakly collisional corona is negligible. The heating rates are larger for weaker background magnetic fields. In addition, higher frequency <span class="hlt">waves</span> are subject to heavier damping. There is an upper cutoff frequency, depending on the background magnetic field, above which the <span class="hlt">waves</span> are completely damped. At the frequencies below which the <span class="hlt">waves</span> are not strongly damped, the <span class="hlt">waves</span> may be strongly reflected at the transition region. The reflected <span class="hlt">waves</span> interacting with the upward <span class="hlt">propagating</span> <span class="hlt">waves</span> may produce power at their double frequencies, which leads to more damping. Due to the reflection and damping, the energy flux of the <span class="hlt">waves</span> transmitted to the corona is one order of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017A%26A...602A..75R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017A%26A...602A..75R"><span>Observations of apparent superslow <span class="hlt">wave</span> <span class="hlt">propagation</span> in solar prominences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Raes, J. O.; Van Doorsselaere, T.; Baes, M.; Wright, A. N.</p> <p>2017-06-01</p> <p>Context. Phase mixing of standing continuum Alfvén <span class="hlt">waves</span> and/or continuum slow <span class="hlt">waves</span> in atmospheric magnetic structures such as coronal arcades can create the apparent effect of a <span class="hlt">wave</span> <span class="hlt">propagating</span> across the magnetic field. Aims: We observe a prominence with SDO/AIA on 2015 March 15 and find the presence of oscillatory motion. We aim to demonstrate that interpreting this motion as a magneto hydrodynamic (MHD) <span class="hlt">wave</span> is faulty. We also connect the decrease of the apparent velocity over time with the phase mixing process, which depends on the curvature of the magnetic field lines. Methods: By measuring the displacement of the prominence at different heights to calculate the apparent velocity, we show that the <span class="hlt">propagation</span> slows down over time, in accordance with the theoretical work of Kaneko et al. We also show that this <span class="hlt">propagation</span> speed drops below what is to be expected for even slow MHD <span class="hlt">waves</span> for those circumstances. We use a modified Kippenhahn-Schlüter prominence model to calculate the curvature of the magnetic field and fit our observations accordingly. Results: Measuring three of the apparent <span class="hlt">waves</span>, we get apparent velocities of 14, 8, and 4 km s-1. Fitting a simple model for the magnetic field configuration, we obtain that the filament is located 103 Mm below the magnetic centre. We also obtain that the scale of the magnetic field strength in the vertical direction plays no role in the concept of apparent superslow <span class="hlt">waves</span> and that the moment of excitation of the <span class="hlt">waves</span> happened roughly one oscillation period before the end of the eruption that excited the oscillation. Conclusions: Some of the observed phase velocities are lower than expected for slow modes for the circumstances, showing that they rather fit with the concept of apparent superslow <span class="hlt">propagation</span>. A fit with our magnetic field model allows for inferring the magnetic geometry of the prominence. The movie attached to Fig. 1 is available at http://www.aanda.org</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1015489','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/servlets/purl/1015489"><span>Estimating <span class="hlt">propagation</span> velocity through a surface acoustic <span class="hlt">wave</span> sensor</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Xu, Wenyuan; Huizinga, John S.</p> <p>2010-03-16</p> <p>Techniques are described for estimating the <span class="hlt">propagation</span> velocity through a surface acoustic <span class="hlt">wave</span> sensor. In particular, techniques which measure and exploit a proper segment of phase frequency response of the surface acoustic <span class="hlt">wave</span> sensor are described for use as a basis of bacterial detection by the sensor. As described, use of velocity estimation based on a proper segment of phase frequency response has advantages over conventional techniques that use phase shift as the basis for detection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1911326J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1911326J"><span>Accelerating <span class="hlt">wave</span> <span class="hlt">propagation</span> modeling in the frequency domain using Python</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jo, Sang Hoon; Park, Min Jun; Ha, Wan Soo</p> <p>2017-04-01</p> <p>Python is a dynamic programming language adopted in many science and engineering areas. We used Python to simulate <span class="hlt">wave</span> <span class="hlt">propagation</span> in the frequency domain. We used the Pardiso matrix solver to solve the impedance matrix of the <span class="hlt">wave</span> equation. Numerical examples shows that Python with numpy consumes longer time to construct the impedance matrix using the finite element method when compared with Fortran; however we could reduce the time significantly to be comparable to that of Fortran using a simple Numba decorator.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DFDG26004M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DFDG26004M"><span>Effect of fuel stratification on detonation <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Masselot, Damien; Fievet, Romain; Raman, Venkat</p> <p>2016-11-01</p> <p>Rotating detonation engines (RDEs) form a class of pressure-gain combustion systems of higher efficiency compared to conventional gas turbine engines. One of the key features of the design is the injection system, as reactants need to be continuously provided to the detonation <span class="hlt">wave</span> to sustain its <span class="hlt">propagation</span> speed. As inhomogeneities in the reactant mixture can perturb the detonation <span class="hlt">wave</span> front, premixed fuel jet injectors might seem like the most stable solution. However, this introduces the risk of the detonation <span class="hlt">wave</span> <span class="hlt">propagating</span> through the injector, causing catastrophic failure. On the other hand, non-premixed fuel injection will tend to quench the detonation <span class="hlt">wave</span> near the injectors, reducing the likelihood of such failure. Still, the effects of such non-premixing and flow inhomogeneities ahead of a detonation <span class="hlt">wave</span> have yet to be fully understood and are the object of this study. A 3D channel filled with O2 diluted in an inert gas with circular H2 injectors is simulated as a detonation <span class="hlt">wave</span> <span class="hlt">propagates</span> through the system. The impact of key parameters such as injector spacing, injector size, mixture composition and time variations will be discussed. PhD Candidate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920051554&hterms=group+theory&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dgroup%2Btheory','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920051554&hterms=group+theory&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dgroup%2Btheory"><span>Linear and nonlinear <span class="hlt">propagation</span> of water <span class="hlt">wave</span> groups</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pierson, W. J., Jr.; Donelan, M. A.; Hui, W. H.</p> <p>1992-01-01</p> <p>Results are presented from a study of the evolution of waveforms with known analytical group shapes, in the form of both transient <span class="hlt">wave</span> groups and the cloidal (cn) and dnoidal (dn) <span class="hlt">wave</span> trains as derived from the nonlinear Schroedinger equation. The waveforms were generated in a long wind-<span class="hlt">wave</span> tank of the Canada Centre for Inland Waters. It was found that the low-amplitude transients behaved as predicted by the linear theory and that the cn and dn <span class="hlt">wave</span> trains of moderate steepness behaved almost as predicted by the nonlinear Schroedinger equation. Some of the results did not fit into any of the available theories for <span class="hlt">waves</span> on water, but they provide important insight on how actual groups of <span class="hlt">waves</span> <span class="hlt">propagate</span> and on higher-order effects for a transient waveform.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JPhCS.991a2047K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JPhCS.991a2047K"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> problem for a micropolar elastic waveguide</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kovalev, V. A.; Murashkin, E. V.; Radayev, Y. N.</p> <p>2018-04-01</p> <p>A <span class="hlt">propagation</span> problem for coupled harmonic <span class="hlt">waves</span> of translational displacements and microrotations along the axis of a long cylindrical waveguide is discussed at present study. Microrotations modeling is carried out within the linear micropolar elasticity frameworks. The mathematical model of the linear (or even nonlinear) micropolar elasticity is also expanded to a field theory model by variational least action integral and the least action principle. The governing coupled vector differential equations of the linear micropolar elasticity are given. The translational displacements and microrotations in the harmonic coupled <span class="hlt">wave</span> are decomposed into potential and vortex parts. Calibrating equations providing simplification of the equations for the <span class="hlt">wave</span> potentials are proposed. The coupled differential equations are then reduced to uncoupled ones and finally to the Helmholtz <span class="hlt">wave</span> equations. The <span class="hlt">wave</span> equations solutions for the translational and microrotational <span class="hlt">waves</span> potentials are obtained for a high-frequency range.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70195105','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70195105"><span>Probabilistic <span class="hlt">tsunami</span> hazard analysis: Multiple sources and global applications</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Grezio, Anita; Babeyko, Andrey; Baptista, Maria Ana; Behrens, Jörn; Costa, Antonio; Davies, Gareth; Geist, Eric L.; Glimsdal, Sylfest; González, Frank I.; Griffin, Jonathan; Harbitz, Carl B.; LeVeque, Randall J.; Lorito, Stefano; Løvholt, Finn; Omira, Rachid; Mueller, Christof; Paris, Raphaël; Parsons, Thomas E.; Polet, Jascha; Power, William; Selva, Jacopo; Sørensen, Mathilde B.; Thio, Hong Kie</p> <p>2017-01-01</p> <p>Applying probabilistic methods to infrequent but devastating natural events is intrinsically challenging. For <span class="hlt">tsunami</span> analyses, a suite of geophysical assessments should be in principle evaluated because of the different causes generating <span class="hlt">tsunamis</span> (earthquakes, landslides, volcanic activity, meteorological events, and asteroid impacts) with varying mean recurrence rates. Probabilistic <span class="hlt">Tsunami</span> Hazard Analyses (PTHAs) are conducted in different areas of the world at global, regional, and local scales with the aim of understanding <span class="hlt">tsunami</span> hazard to inform <span class="hlt">tsunami</span> risk reduction activities. PTHAs enhance knowledge of the potential tsunamigenic threat by estimating the probability of exceeding specific levels of <span class="hlt">tsunami</span> intensity metrics (e.g., run-up or maximum inundation heights) within a certain period of time (exposure time) at given locations (target sites); these estimates can be summarized in hazard maps or hazard curves. This discussion presents a broad overview of PTHA, including (i) sources and mechanisms of <span class="hlt">tsunami</span> generation, emphasizing the variety and complexity of the <span class="hlt">tsunami</span> sources and their generation mechanisms, (ii) developments in modeling the <span class="hlt">propagation</span> and impact of <span class="hlt">tsunami</span> <span class="hlt">waves</span>, and (iii) statistical procedures for <span class="hlt">tsunami</span> hazard estimates that include the associated epistemic and aleatoric uncertainties. Key elements in understanding the potential <span class="hlt">tsunami</span> hazard are discussed, in light of the rapid development of PTHA methods during the last decade and the globally distributed applications, including the importance of considering multiple sources, their relative intensities, probabilities of occurrence, and uncertainties in an integrated and consistent probabilistic framework.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017RvGeo..55.1158G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017RvGeo..55.1158G"><span>Probabilistic <span class="hlt">Tsunami</span> Hazard Analysis: Multiple Sources and Global Applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grezio, Anita; Babeyko, Andrey; Baptista, Maria Ana; Behrens, Jörn; Costa, Antonio; Davies, Gareth; Geist, Eric L.; Glimsdal, Sylfest; González, Frank I.; Griffin, Jonathan; Harbitz, Carl B.; LeVeque, Randall J.; Lorito, Stefano; Løvholt, Finn; Omira, Rachid; Mueller, Christof; Paris, Raphaël.; Parsons, Tom; Polet, Jascha; Power, William; Selva, Jacopo; Sørensen, Mathilde B.; Thio, Hong Kie</p> <p>2017-12-01</p> <p>Applying probabilistic methods to infrequent but devastating natural events is intrinsically challenging. For <span class="hlt">tsunami</span> analyses, a suite of geophysical assessments should be in principle evaluated because of the different causes generating <span class="hlt">tsunamis</span> (earthquakes, landslides, volcanic activity, meteorological events, and asteroid impacts) with varying mean recurrence rates. Probabilistic <span class="hlt">Tsunami</span> Hazard Analyses (PTHAs) are conducted in different areas of the world at global, regional, and local scales with the aim of understanding <span class="hlt">tsunami</span> hazard to inform <span class="hlt">tsunami</span> risk reduction activities. PTHAs enhance knowledge of the potential tsunamigenic threat by estimating the probability of exceeding specific levels of <span class="hlt">tsunami</span> intensity metrics (e.g., run-up or maximum inundation heights) within a certain period of time (exposure time) at given locations (target sites); these estimates can be summarized in hazard maps or hazard curves. This discussion presents a broad overview of PTHA, including (i) sources and mechanisms of <span class="hlt">tsunami</span> generation, emphasizing the variety and complexity of the <span class="hlt">tsunami</span> sources and their generation mechanisms, (ii) developments in modeling the <span class="hlt">propagation</span> and impact of <span class="hlt">tsunami</span> <span class="hlt">waves</span>, and (iii) statistical procedures for <span class="hlt">tsunami</span> hazard estimates that include the associated epistemic and aleatoric uncertainties. Key elements in understanding the potential <span class="hlt">tsunami</span> hazard are discussed, in light of the rapid development of PTHA methods during the last decade and the globally distributed applications, including the importance of considering multiple sources, their relative intensities, probabilities of occurrence, and uncertainties in an integrated and consistent probabilistic framework.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AcMSn..31....1Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AcMSn..31....1Z"><span>Modeling ocean <span class="hlt">wave</span> <span class="hlt">propagation</span> under sea ice covers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Xin; Shen, Hayley H.; Cheng, Sukun</p> <p>2015-02-01</p> <p>Operational ocean <span class="hlt">wave</span> models need to work globally, yet current ocean <span class="hlt">wave</span> models can only treat ice-covered regions crudely. The purpose of this paper is to provide a brief overview of ice effects on <span class="hlt">wave</span> <span class="hlt">propagation</span> and different research methodology used in studying these effects. Based on its proximity to land or sea, sea ice can be classified as: landfast ice zone, shear zone, and the marginal ice zone. All ice covers attenuate <span class="hlt">wave</span> energy. Only long swells can penetrate deep into an ice cover. Being closest to open water, <span class="hlt">wave</span> <span class="hlt">propagation</span> in the marginal ice zone is the most complex to model. The physical appearance of sea ice in the marginal ice zone varies. Grease ice, pancake ice, brash ice, floe aggregates, and continuous ice sheet may be found in this zone at different times and locations. These types of ice are formed under different thermal-mechanical forcing. There are three classic models that describe <span class="hlt">wave</span> <span class="hlt">propagation</span> through an idealized ice cover: mass loading, thin elastic plate, and viscous layer models. From physical arguments we may conjecture that mass loading model is suitable for disjoint aggregates of ice floes much smaller than the wavelength, thin elastic plate model is suitable for a continuous ice sheet, and the viscous layer model is suitable for grease ice. For different sea ice types we may need different <span class="hlt">wave</span> ice interaction models. A recently proposed viscoelastic model is able to synthesize all three classic models into one. Under suitable limiting conditions it converges to the three previous models. The complete theoretical framework for evaluating <span class="hlt">wave</span> <span class="hlt">propagation</span> through various ice covers need to be implemented in the operational ocean <span class="hlt">wave</span> models. In this review, we introduce the sea ice types, previous <span class="hlt">wave</span> ice interaction models, <span class="hlt">wave</span> attenuation mechanisms, the methods to calculate <span class="hlt">wave</span> reflection and transmission between different ice covers, and the effect of ice floe breaking on shaping the sea ice morphology</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PTEP.2018d1E01Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PTEP.2018d1E01Y"><span>Electromagnetic <span class="hlt">waves</span> <span class="hlt">propagating</span> in the string axiverse</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yoshida, Daiske; Soda, Jiro</p> <p>2018-04-01</p> <p>It is widely believed that axions are ubiquitous in string theory and could be dark matter. The peculiar features of axion dark matter are coherent oscillations and a coupling to the electromagnetic field through the Chern-Simons term. In this letter, we study the consequences of these two features of axions with mass in the range 10^{-13} eV to 103 eV. First, we study the parametric resonance of electromagnetic <span class="hlt">waves</span> induced by the coherent oscillation of the axion. Since the resonance frequency is determined by the mass of the axion dark matter, if we detect this signal, we can get information on the mass of the axion dark matter. Second, we study the velocity of light in the background of the axion dark matter. In the presence of the Chern-Simons term, the dispersion relation is modified and the speed of light will oscillate in time. It turns out that the change in the speed of light would be difficult to observe. We argue that future radio <span class="hlt">wave</span> observations of the resonance can give rise to a stronger constraint on the coupling constant and/or the density of the axion dark matter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRE..123..206S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRE..123..206S"><span>Seismic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Icy Ocean Worlds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stähler, Simon C.; Panning, Mark P.; Vance, Steven D.; Lorenz, Ralph D.; van Driel, Martin; Nissen-Meyer, Tarje; Kedar, Sharon</p> <p>2018-01-01</p> <p>Seismology was developed on Earth and shaped our model of the Earth's interior over the twentieth century. With the exception of the Philae lander, all in situ extraterrestrial seismological effort to date was limited to other terrestrial planets. All have in common a rigid crust above a solid mantle. The coming years may see the installation of seismometers on Europa, Titan, and Enceladus, so it is necessary to adapt seismological concepts to the setting of worlds with global oceans covered in ice. Here we use waveform analyses to identify and classify <span class="hlt">wave</span> types, developing a lexicon for icy ocean world seismology intended to be useful to both seismologists and planetary scientists. We use results from spectral-element simulations of broadband seismic wavefields to adapt seismological concepts to icy ocean worlds. We present a concise naming scheme for seismic <span class="hlt">waves</span> and an overview of the features of the seismic wavefield on Europa, Titan, Ganymede, and Enceladus. In close connection with geophysical interior models, we analyze simulated seismic measurements of Europa and Titan that might be used to constrain geochemical parameters governing the habitability of a sub-ice ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1215511-corrigendum-addendum-modeling-weakly-nonlinear-acoustic-wave-propagation','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1215511-corrigendum-addendum-modeling-weakly-nonlinear-acoustic-wave-propagation"><span>Corrigendum and addendum. Modeling weakly nonlinear acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Christov, Ivan; Christov, C. I.; Jordan, P. M.</p> <p>2014-12-18</p> <p>This article presents errors, corrections, and additions to the research outlined in the following citation: Christov, I., Christov, C. I., & Jordan, P. M. (2007). Modeling weakly nonlinear acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span>. The Quarterly Journal of Mechanics and Applied Mathematics, 60(4), 473-495.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19720018128','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19720018128"><span>Millimeter <span class="hlt">wave</span> <span class="hlt">propagation</span> measurements using the ATS 5 satellite</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ippolito, L. J.</p> <p>1972-01-01</p> <p>The ATS 5 millimeter <span class="hlt">wave</span> <span class="hlt">propagation</span> experiment determines long- and short-term attenuation statistics of operational millimeter wavelength earthspace links as functions of defined meteorological conditions. A preliminary analysis of results with 15 GHz downlink and 32 GHz uplink frequency bands indicates that both frequency bands exhibit an excellent potential for utilization in reliable high data rate earth-space communications systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3777432','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3777432"><span>A k-Space Method for Moderately Nonlinear <span class="hlt">Wave</span> <span class="hlt">Propagation</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Jing, Yun; Wang, Tianren; Clement, Greg T.</p> <p>2013-01-01</p> <p>A k-space method for moderately nonlinear <span class="hlt">wave</span> <span class="hlt">propagation</span> in absorptive media is presented. The Westervelt equation is first transferred into k-space via Fourier transformation, and is solved by a modified <span class="hlt">wave</span>-vector time-domain scheme. The present approach is not limited to forward <span class="hlt">propagation</span> or parabolic approximation. One- and two-dimensional problems are investigated to verify the method by comparing results to analytic solutions and finite-difference time-domain (FDTD) method. It is found that to obtain accurate results in homogeneous media, the grid size can be as little as two points per wavelength, and for a moderately nonlinear problem, the Courant–Friedrichs–Lewy number can be as large as 0.4. Through comparisons with the conventional FDTD method, the k-space method for nonlinear <span class="hlt">wave</span> <span class="hlt">propagation</span> is shown here to be computationally more efficient and accurate. The k-space method is then employed to study three-dimensional nonlinear <span class="hlt">wave</span> <span class="hlt">propagation</span> through the skull, which shows that a relatively accurate focusing can be achieved in the brain at a high frequency by sending a low frequency from the transducer. Finally, implementations of the k-space method using a single graphics processing unit shows that it required about one-seventh the computation time of a single-core CPU calculation. PMID:22899114</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3081171','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3081171"><span>Electromagnetic <span class="hlt">wave</span> <span class="hlt">propagation</span> in rain and polarization effects</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>OKAMURA, Sogo; OGUCHI, Tomohiro</p> <p>2010-01-01</p> <p>This paper summarizes our study on microwave and millimeter-<span class="hlt">wave</span> <span class="hlt">propagation</span> in rain with special emphasis on the effects of polarization. Starting from a recount of our past findings, we will discuss developments with these and how they are connected with subsequent research. PMID:20551593</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19780021366','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19780021366"><span>A compendium of millimeter <span class="hlt">wave</span> <span class="hlt">propagation</span> studies performed by NASA</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kaul, R.; Rogers, D.; Bremer, J.</p> <p>1977-01-01</p> <p>Key millimeter <span class="hlt">wave</span> <span class="hlt">propagation</span> experiments and analytical results were summarized. The experiments were performed with the Ats-5, Ats-6 and Comstar satellites, radars, radiometers and rain gage networks. Analytic models were developed for extrapolation of experimental results to frequencies, locations, and communications systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://rosap.ntl.bts.gov/view/dot/11748','DOTNTL'); return false;" href="https://rosap.ntl.bts.gov/view/dot/11748"><span>Bibliography and Comments on Loran-C Ground <span class="hlt">Wave</span> <span class="hlt">Propagation</span></span></a></p> <p><a target="_blank" href="http://ntlsearch.bts.gov/tris/index.do">DOT National Transportation Integrated Search</a></p> <p></p> <p>1977-12-01</p> <p>The report contains a selected bibliography of work dealing with ground <span class="hlt">wave</span> <span class="hlt">propagation</span> of Loran-C signals. The selected works include reports of both theoretical and measurement activities over both water and land. A summary of and comments on Lora...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFM.T22B1157T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFM.T22B1157T"><span>Nonlinear <span class="hlt">Wave</span> <span class="hlt">propagation</span> at sediment layers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tsuda, K.; Archuleta, R. J.; O'Connell, D. R.; Bonilla, F. L.</p> <p>2002-12-01</p> <p>Data from some large earthquakes, such as the 2000 Tottoriken-Seibu earthquake, the 1995 Kobe earthquake, and 1994 Northridge earthquake have reinforced the importance of the effect of surface soil on seismic <span class="hlt">waves</span>. This is especially true of the Tottoriken-Seibu earthquake where the damage from the liquefaction of surface soil was very severe. The mechanism of the liquefaction of soil is understood as the result of the nonlinear soil behavior-the pore water pressure build up-during the strong shaking. The model to explain the mechanics of pore water pressure build up has been proposed by many studies. In this study, we tried to predict the pore water pressure based on the constitutive model proposed by Iai et al. (1992). This model has been already applied to predict nonlinear soil behavior by Bonilla (2000) whose simulated results showed good agreement with the laboratory data in the VELACS program. We have applied this method to simulate ground motions at Jackson Lake Dam, Wyoming. We constructed a 140 m one-dimensional shear-<span class="hlt">wave</span> velocity/depth profile for the sediment layers. The water table is at 2 m depth. The elastic material properties are based on in situ measurements. However, the parameters needed for the nonlinear response are taken from generic data for similar materials. To check for consistency we have constructed liquefaction resistance curves using a range of parameters that will be assumed for the soil column. These curves are compared with measured point values of the liquefaction resistance. To estimate the response at Jackson Lake Dam we have used strong motion records-JMA records from the 1995 Kobe earthquake and the Pleasant Valley Pumping Plant records from the 1983 Coalinga earthquake-as input motions at 140 m depth. We have also used synthetic ground motions computed from scenario earthquakes that might occur on the Teton Fault, very close to the dam. In the case of the synthetic input motions, the calculated shear strain approaches 20</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PApGe.tmp...33G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PApGe.tmp...33G"><span>Effect of Dynamical Phase on the Resonant Interaction Among <span class="hlt">Tsunami</span> Edge <span class="hlt">Wave</span> Modes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Geist, Eric L.</p> <p>2018-02-01</p> <p>Different modes of <span class="hlt">tsunami</span> edge <span class="hlt">waves</span> can interact through nonlinear resonance. During this process, edge <span class="hlt">waves</span> that have very small initial amplitude can grow to be as large or larger than the initially dominant edge <span class="hlt">wave</span> modes. In this study, the effects of dynamical phase are established for a single triad of edge <span class="hlt">waves</span> that participate in resonant interactions. In previous studies, Jacobi elliptic functions were used to describe the slow variation in amplitude associated with the interaction. This analytical approach assumes that one of the edge <span class="hlt">waves</span> in the triad has zero initial amplitude and that the combined phase of the three <span class="hlt">waves</span> φ = θ 1 + θ 2 - θ 3 is constant at the value for maximum energy exchange (φ = 0). To obtain a more general solution, dynamical phase effects and non-zero initial amplitudes for all three <span class="hlt">waves</span> are incorporated using numerical methods for the governing differential equations. Results were obtained using initial conditions calculated from a subduction zone, inter-plate thrust fault geometry and a stochastic earthquake slip model. The effect of dynamical phase is most apparent when the initial amplitudes and frequencies of the three <span class="hlt">waves</span> are within an order of magnitude. In this case, non-zero initial phase results in a marked decrease in energy exchange and a slight decrease in the period of the interaction. When there are large differences in frequency and/or initial amplitude, dynamical phase has less of an effect and typically one <span class="hlt">wave</span> of the triad has very little energy exchange with the other two <span class="hlt">waves</span>. Results from this study help elucidate under what conditions edge <span class="hlt">waves</span> might be implicated in late, large-amplitude arrivals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70196713','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70196713"><span>Effect of dynamical phase on the resonant interaction among <span class="hlt">tsunami</span> edge <span class="hlt">wave</span> modes</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, Eric L.</p> <p>2018-01-01</p> <p>Different modes of <span class="hlt">tsunami</span> edge <span class="hlt">waves</span> can interact through nonlinear resonance. During this process, edge <span class="hlt">waves</span> that have very small initial amplitude can grow to be as large or larger than the initially dominant edge <span class="hlt">wave</span> modes. In this study, the effects of dynamical phase are established for a single triad of edge <span class="hlt">waves</span> that participate in resonant interactions. In previous studies, Jacobi elliptic functions were used to describe the slow variation in amplitude associated with the interaction. This analytical approach assumes that one of the edge <span class="hlt">waves</span> in the triad has zero initial amplitude and that the combined phase of the three <span class="hlt">waves</span> φ = θ1 + θ2 − θ3 is constant at the value for maximum energy exchange (φ = 0). To obtain a more general solution, dynamical phase effects and non-zero initial amplitudes for all three <span class="hlt">waves</span> are incorporated using numerical methods for the governing differential equations. Results were obtained using initial conditions calculated from a subduction zone, inter-plate thrust fault geometry and a stochastic earthquake slip model. The effect of dynamical phase is most apparent when the initial amplitudes and frequencies of the three <span class="hlt">waves</span> are within an order of magnitude. In this case, non-zero initial phase results in a marked decrease in energy exchange and a slight decrease in the period of the interaction. When there are large differences in frequency and/or initial amplitude, dynamical phase has less of an effect and typically one <span class="hlt">wave</span> of the triad has very little energy exchange with the other two <span class="hlt">waves</span>. Results from this study help elucidate under what conditions edge <span class="hlt">waves</span> might be implicated in late, large-amplitude arrivals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PApGe.175.1341G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PApGe.175.1341G"><span>Effect of Dynamical Phase on the Resonant Interaction Among <span class="hlt">Tsunami</span> Edge <span class="hlt">Wave</span> Modes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Geist, Eric L.</p> <p>2018-04-01</p> <p>Different modes of <span class="hlt">tsunami</span> edge <span class="hlt">waves</span> can interact through nonlinear resonance. During this process, edge <span class="hlt">waves</span> that have very small initial amplitude can grow to be as large or larger than the initially dominant edge <span class="hlt">wave</span> modes. In this study, the effects of dynamical phase are established for a single triad of edge <span class="hlt">waves</span> that participate in resonant interactions. In previous studies, Jacobi elliptic functions were used to describe the slow variation in amplitude associated with the interaction. This analytical approach assumes that one of the edge <span class="hlt">waves</span> in the triad has zero initial amplitude and that the combined phase of the three <span class="hlt">waves</span> φ = θ 1 + θ 2 - θ 3 is constant at the value for maximum energy exchange ( φ = 0). To obtain a more general solution, dynamical phase effects and non-zero initial amplitudes for all three <span class="hlt">waves</span> are incorporated using numerical methods for the governing differential equations. Results were obtained using initial conditions calculated from a subduction zone, inter-plate thrust fault geometry and a stochastic earthquake slip model. The effect of dynamical phase is most apparent when the initial amplitudes and frequencies of the three <span class="hlt">waves</span> are within an order of magnitude. In this case, non-zero initial phase results in a marked decrease in energy exchange and a slight decrease in the period of the interaction. When there are large differences in frequency and/or initial amplitude, dynamical phase has less of an effect and typically one <span class="hlt">wave</span> of the triad has very little energy exchange with the other two <span class="hlt">waves</span>. Results from this study help elucidate under what conditions edge <span class="hlt">waves</span> might be implicated in late, large-amplitude arrivals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS11C1651A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS11C1651A"><span>Errors in <span class="hlt">Tsunami</span> Source Estimation from Tide Gauges</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arcas, D.</p> <p>2012-12-01</p> <p>Linearity of <span class="hlt">tsunami</span> <span class="hlt">waves</span> in deep water can be assessed as a comparison of flow speed, u to <span class="hlt">wave</span> <span class="hlt">propagation</span> speed √gh. In real <span class="hlt">tsunami</span> scenarios this evaluation becomes impractical due to the absence of observational data of <span class="hlt">tsunami</span> flow velocities in shallow water. Consequently the extent of validity of the linear regime in the ocean is unclear. Linearity is the fundamental assumption behind <span class="hlt">tsunami</span> source inversion processes based on linear combinations of unit <span class="hlt">propagation</span> runs from a deep water <span class="hlt">propagation</span> database (Gica et al., 2008). The primary <span class="hlt">tsunami</span> elevation data for such inversion is usually provided by National Oceanic and Atmospheric (NOAA) deep-water <span class="hlt">tsunami</span> detection systems known as DART. The use of tide gauge data for such inversions is more controversial due to the uncertainty of <span class="hlt">wave</span> linearity at the depth of the tide gauge site. This study demonstrates the inaccuracies incurred in source estimation using tide gauge data in conjunction with a linear combination procedure for <span class="hlt">tsunami</span> source estimation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009JGRC..11412025T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009JGRC..11412025T"><span>Development, testing, and applications of site-specific <span class="hlt">tsunami</span> inundation models for real-time forecasting</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tang, L.; Titov, V. V.; Chamberlin, C. D.</p> <p>2009-12-01</p> <p>The study describes the development, testing and applications of site-specific <span class="hlt">tsunami</span> inundation models (forecast models) for use in NOAA's <span class="hlt">tsunami</span> forecast and warning system. The model development process includes sensitivity studies of <span class="hlt">tsunami</span> <span class="hlt">wave</span> characteristics in the nearshore and inundation, for a range of model grid setups, resolutions and parameters. To demonstrate the process, four forecast models in Hawaii, at Hilo, Kahului, Honolulu, and Nawiliwili are described. The models were validated with fourteen historical <span class="hlt">tsunamis</span> and compared with numerical results from reference inundation models of higher resolution. The accuracy of the modeled maximum <span class="hlt">wave</span> height is greater than 80% when the observation is greater than 0.5 m; when the observation is below 0.5 m the error is less than 0.3 m. The error of the modeled arrival time of the first peak is within 3% of the travel time. The developed forecast models were further applied to hazard assessment from simulated magnitude 7.5, 8.2, 8.7 and 9.3 <span class="hlt">tsunamis</span> based on subduction zone earthquakes in the Pacific. The <span class="hlt">tsunami</span> hazard assessment study indicates that use of a seismic magnitude alone for a <span class="hlt">tsunami</span> source assessment is inadequate to achieve such accuracy for <span class="hlt">tsunami</span> amplitude forecasts. The forecast models apply local bathymetric and topographic information, and utilize dynamic boundary conditions from the <span class="hlt">tsunami</span> source function database, to provide site- and event-specific coastal predictions. Only by combining a Deep-ocean Assessment and Reporting of <span class="hlt">Tsunami</span>-constrained <span class="hlt">tsunami</span> magnitude with site-specific high-resolution models can the forecasts completely cover the evolution of earthquake-generated <span class="hlt">tsunami</span> <span class="hlt">waves</span>: generation, deep ocean <span class="hlt">propagation</span>, and coastal inundation. Wavelet analysis of the <span class="hlt">tsunami</span> <span class="hlt">waves</span> suggests the coastal <span class="hlt">tsunami</span> frequency responses at different sites are dominated by the local bathymetry, yet they can be partially related to the locations of the <span class="hlt">tsunami</span> sources. The study</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PApGe.172.1679L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PApGe.172.1679L"><span>Advanced <span class="hlt">Tsunami</span> Numerical Simulations and Energy Considerations by use of 3D-2D Coupled Models: The October 11, 1918, Mona Passage <span class="hlt">Tsunami</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>López-Venegas, Alberto M.; Horrillo, Juan; Pampell-Manis, Alyssa; Huérfano, Victor; Mercado, Aurelio</p> <p>2015-06-01</p> <p>The most recent <span class="hlt">tsunami</span> observed along the coast of the island of Puerto Rico occurred on October 11, 1918, after a magnitude 7.2 earthquake in the Mona Passage. The earthquake was responsible for initiating a <span class="hlt">tsunami</span> that mostly affected the northwestern coast of the island. Runup values from a post-<span class="hlt">tsunami</span> survey indicated the <span class="hlt">waves</span> reached up to 6 m. A controversy regarding the source of the <span class="hlt">tsunami</span> has resulted in several numerical simulations involving either fault rupture or a submarine landslide as the most probable cause of the <span class="hlt">tsunami</span>. Here we follow up on previous simulations of the <span class="hlt">tsunami</span> from a submarine landslide source off the western coast of Puerto Rico as initiated by the earthquake. Improvements on our previous study include: (1) higher-resolution bathymetry; (2) a 3D-2D coupled numerical model specifically developed for the <span class="hlt">tsunami</span>; (3) use of the non-hydrostatic numerical model NEOWAVE (non-hydrostatic evolution of ocean <span class="hlt">WAVE</span>) featuring two-way nesting capabilities; and (4) comprehensive energy analysis to determine the time of full <span class="hlt">tsunami</span> <span class="hlt">wave</span> development. The three-dimensional Navier-Stokes model <span class="hlt">tsunami</span> solution using the Navier-Stokes algorithm with multiple interfaces for two fluids (water and landslide) was used to determine the initial <span class="hlt">wave</span> characteristic generated by the submarine landslide. Use of NEOWAVE enabled us to solve for coastal inundation, <span class="hlt">wave</span> <span class="hlt">propagation</span>, and detailed runup. Our results were in agreement with previous work in which a submarine landslide is favored as the most probable source of the <span class="hlt">tsunami</span>, and improvement in the resolution of the bathymetry yielded inundation of the coastal areas that compare well with values from a post-<span class="hlt">tsunami</span> survey. Our unique energy analysis indicates that most of the <span class="hlt">wave</span> energy is isolated in the <span class="hlt">wave</span> generation region, particularly at depths near the landslide, and once the initial <span class="hlt">wave</span> <span class="hlt">propagates</span> from the generation region its energy begins to stabilize.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1816602P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1816602P"><span>Seismic Shaking, <span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Erosion And Generation of Seismo-Turbidites in the Ionian Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Polonia, Alina; Nelson, Hans; Romano, Stefania; Vaiani, Stefano Claudio; Colizza, Ester; Gasparotto, Giorgio; Gasperini, Luca</p> <p>2016-04-01</p> <p>We are investigating the effects of earthquakes and <span class="hlt">tsunamis</span> on the sedimentary record in the Ionian Sea through the analysis of turbidite deposits. A comparison between radiometric dating and historical earthquake catalogs suggests that recent turbidite generation is triggered by great earthquakes in the Calabrian and hellenic Arcs such as the AD 1908 Messina, AD 1693 Catania, AD 1169 Eastern Sicily and AD 365 Crete earthquakes. Textural, micropaleontological, geochemical and mineralogical signatures of the youngest three seismo-turbidites reveal cyclic patterns of sedimentary units. The basal stacked turbidites result from multiple slope failure sources as shown by different sedimentary structures as well as mineralogic, geochemical and micropaleontological compositions. The homogenite units, are graded muds deposited from the waning flows of the multiple turbidity currents that are trapped in the Ionian Sea confined basin. The uppermost unit is divided into two parts. The lower marine sourced laminated part without textural gradation, we interpret to result from seiching of the confined water mass that appears to be generated by earthquake ruptures combined with <span class="hlt">tsunami</span> <span class="hlt">waves</span>. The uppermost part we interpret as the tsunamite cap that is deposited by the slow settling suspension cloud created by <span class="hlt">tsunami</span> <span class="hlt">wave</span> backwash erosion of the shoreline and continental shelf. This <span class="hlt">tsunami</span> process interpretation is based on the final textural gradation of the upper unit and a more continental source of the <span class="hlt">tsunami</span> cap which includes C/N >10, the lack of abyssal foraminifera species wirth the local occurrence of inner shelf foraminifera. Seismic reflection images show that some deeper turbidite beds are very thick and marked by acoustic transparent homogenite mud layers at their top. Based on a high resolution study of the most recent of such megabeds (Homogenite/Augias turbidite, i.e. HAT), we show that it was triggered by the AD 365 Crete earthquake. Radiometric dating</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19940004262&hterms=Lamb&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DLamb','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19940004262&hterms=Lamb&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DLamb"><span>Experimental and theoretical study of Rayleigh-Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rogers, Wayne P.; Datta, Subhendu K.; Ju, T. H.</p> <p>1990-01-01</p> <p>Many space structures, such as the Space Station Freedom, contain critical thin-walled components. The structural integrity of thin-walled plates and shells can be monitored effectively using acoustic emission and ultrasonic testing in the Rayleigh-Lamb <span class="hlt">wave</span> frequency range. A new PVDF piezoelectric sensor has been developed that is well suited to remote, inservice nondestructive evaluation of space structures. In the present study the new sensor was used to investigate Rayleigh-Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> in a plate. The experimental apparatus consisted of a glass plate (2.3 m x 25.4 mm x 5.6 mm) with PVDF sensor (3 mm diam.) mounted at various positions along its length. A steel ball impact served as a simulated acoustic emission source, producing surface <span class="hlt">waves</span>, shear <span class="hlt">waves</span> and longitudinal <span class="hlt">waves</span> with dominant frequencies between 1 kHz and 200 kHz. The experimental time domain <span class="hlt">wave</span>-forms were compared with theoretical predictions of the <span class="hlt">wave</span> <span class="hlt">propagation</span> in the plate. The model uses an analytical solution for the Green's function and the measured response at a single position to predict response at any other position in the plate. Close agreement was found between the experimental and theoretical results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018OcMod.124...61B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018OcMod.124...61B"><span>Amplification of drawdown and runup over Hawaii's insular shelves by <span class="hlt">tsunami</span> N-<span class="hlt">waves</span> from mega Aleutian earthquakes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bai, Yefei; Yamazaki, Yoshiki; Cheung, Kwok Fai</p> <p>2018-04-01</p> <p>The latest <span class="hlt">tsunami</span> evacuation maps of Hawaii include an extreme scenario triggered by an Mw 9.3 Aleutian earthquake with large near-trench rupture. The tectonic plate motion produces concentrated seafloor uplift toward the deepest part of the trench generating a <span class="hlt">tsunami</span> with strong non-hydrostatic characters. A parametric study shows the skewed seafloor uplift produces a dispersive leading crest followed by a prominent trough in the form of an N-<span class="hlt">wave</span>. The trough maintains its depth across the ocean in the absence of side lobes and dispersion. Shifting of the uplift toward the trench tends to deepen the trough, but has diminishing effects on the <span class="hlt">wave</span> crest away from the source. While the attenuated leading crest produces relatively moderate runup on north-facing shores of the Hawaiian Islands, with matching of the N-<span class="hlt">wave</span> and shelf resonance periods, the trough produces an impulsive drawdown followed by an energetic upswing with unprecedented runup for a far-field <span class="hlt">tsunami</span>. A set of control computations without dispersion reaffirms that a non-hydrostatic model is essential to account for these complex <span class="hlt">wave</span> processes from the source to the shore. This case study highlights the unique <span class="hlt">tsunami</span> hazards posed by the Aleutians to Hawaii and the role of <span class="hlt">wave</span> troughs in delineating the impacts for hazard assessment and engineering design.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPC.1899f0006Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPC.1899f0006Z"><span>Mathematical investigation of <span class="hlt">tsunami</span>-like long <span class="hlt">waves</span> interaction with submerge dike of different thickness</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhiltsov, Konstantin; Kostyushin, Kirill; Kagenov, Anuar; Tyryshkin, Ilya</p> <p>2017-11-01</p> <p>This paper presents a mathematical investigation of the interaction of a long <span class="hlt">tsunami</span>-type <span class="hlt">wave</span> with a submerge dike. The calculations were performed by using the freeware package OpenFOAM. Unsteady two-dimensional Navier-Stokes equations were used for mathematical modeling of incompressible two-phase medium. The Volume of Fluid (VOF) method is used to capture the free surface of a liquid. The effects caused by long <span class="hlt">wave</span> of defined amplitude motion through a submerged dike of varying thickness were discussed in detail. Numerical results show that after <span class="hlt">wave</span> passing through the barrier, multiple vortex structures were formed behind. Intensity of vortex depended on the size of the barrier. The effectiveness of the submerge barrier was estimated by evaluating the <span class="hlt">wave</span> reflection and transmission coefficients using the energy integral method. Then, the curves of the dependences of the reflection and transmission coefficients were obtained for the interaction of <span class="hlt">waves</span> with the dike. Finally, it was confirmed that the energy of the <span class="hlt">wave</span> could be reduced by more than 50% when it passed through the barrier.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/sir/2010/5013/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/sir/2010/5013/"><span>S-<span class="hlt">Wave</span> Normal Mode <span class="hlt">Propagation</span> in Aluminum Cylinders</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Lee, Myung W.; Waite, William F.</p> <p>2010-01-01</p> <p>Large amplitude waveform features have been identified in pulse-transmission shear-<span class="hlt">wave</span> measurements through cylinders that are long relative to the acoustic wavelength. The arrival times and amplitudes of these features do not follow the predicted behavior of well-known bar <span class="hlt">waves</span>, but instead they appear to <span class="hlt">propagate</span> with group velocities that increase as the waveform feature's dominant frequency increases. To identify these anomalous features, the <span class="hlt">wave</span> equation is solved in a cylindrical coordinate system using an infinitely long cylinder with a free surface boundary condition. The solution indicates that large amplitude normal-mode <span class="hlt">propagations</span> exist. Using the high-frequency approximation of the Bessel function, an approximate dispersion relation is derived. The predicted amplitude and group velocities using the approximate dispersion relation qualitatively agree with measured values at high frequencies, but the exact dispersion relation should be used to analyze normal modes for full ranges of frequency of interest, particularly at lower frequencies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005JAP....97d4307N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005JAP....97d4307N"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> of carbon nanotubes embedded in an elastic medium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Natsuki, Toshiaki; Hayashi, Takuya; Endo, Morinobu</p> <p>2005-02-01</p> <p>This paper presents analytical models of <span class="hlt">wave</span> <span class="hlt">propagation</span> in single- and double-walled carbon nanotubes, as well as nanotubes embedded in an elastic matrix. The nanotube structures are treated within the multilayer thin shell approximation with the elastic properties taken to be those of the graphene sheet. The double-walled nanotubes are coupled together through the van der Waals force between the inner and outer nanotubes. For carbon nanotubes embedded in an elastic matrix, the surrounding elastic medium can be described by a Winkler model. Tube <span class="hlt">wave</span> <span class="hlt">propagation</span> of both symmetrical and asymmetrical modes can be analyzed based on the present elastic continuum model. It is found that the asymmetrical <span class="hlt">wave</span> behavior of single- and double-walled nanotubes is significantly different. The behavior is also different from that in the surrounding elastic medium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950013131','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950013131"><span>Simulation of <span class="hlt">wave</span> <span class="hlt">propagation</span> in three-dimensional random media</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Coles, William A.; Filice, J. P.; Frehlich, R. G.; Yadlowsky, M.</p> <p>1993-01-01</p> <p>Quantitative error analysis for simulation of <span class="hlt">wave</span> <span class="hlt">propagation</span> in three dimensional random media assuming narrow angular scattering are presented for the plane <span class="hlt">wave</span> and spherical <span class="hlt">wave</span> geometry. This includes the errors resulting from finite grid size, finite simulation dimensions, and the separation of the two-dimensional screens along the <span class="hlt">propagation</span> direction. Simple error scalings are determined for power-law spectra of the random refractive index of the media. The effects of a finite inner scale are also considered. The spatial spectra of the intensity errors are calculated and compared to the spatial spectra of intensity. The numerical requirements for a simulation of given accuracy are determined for realizations of the field. The numerical requirements for accurate estimation of higher moments of the field are less stringent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26392614','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26392614"><span>The meteorite impact-induced <span class="hlt">tsunami</span> hazard.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wünnemann, K; Weiss, R</p> <p>2015-10-28</p> <p>When a cosmic object strikes the Earth, it most probably falls into an ocean. Depending on the impact energy and the depth of the ocean, a large amount of water is displaced, forming a temporary crater in the water column. Large <span class="hlt">tsunami</span>-like <span class="hlt">waves</span> originate from the collapse of the cavity in the water and the ejecta splash. Because of the far-reaching destructive consequences of such <span class="hlt">waves</span>, an oceanic impact has been suggested to be more severe than a similar-sized impact on land; in other words, oceanic impacts may punch over their weight. This review paper summarizes the process of impact-induced <span class="hlt">wave</span> generation and subsequent <span class="hlt">propagation</span>, whether the <span class="hlt">wave</span> characteristic differs from <span class="hlt">tsunamis</span> generated by other classical mechanisms, and what methods have been applied to quantify the consequences of an oceanic impact. Finally, the impact-induced <span class="hlt">tsunami</span> hazard will be evaluated by means of the Eltanin impact event. © 2015 The Author(s).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170000013&hterms=tsunami&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dtsunami','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170000013&hterms=tsunami&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dtsunami"><span><span class="hlt">Tsunami</span> <span class="hlt">Waves</span> Extensively Resurfaced the Shorelines of an Early Martian Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rodriguez, J. A. P.; Fairen, A. G.; Linares, R.; Zarroca, M.; Platz, T.; Komatsu, G.; Kargel, J. S.; Gulick, V.; Jianguo, Y.; Higuchi, K.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20170000013'); toggleEditAbsImage('author_20170000013_show'); toggleEditAbsImage('author_20170000013_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20170000013_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170000013_hide"></p> <p>2016-01-01</p> <p>Viking image-based mapping of a widespread deposit covering most of the northern low-lands of Mars led to the proposal by Parker et al. that the deposit represents the vestiges of an enormous ocean that existed approx. 3.4 Ga. Later identified as the Vastitas Borealis Formation, the latest geologic map of Mars identifies this deposit as the Late Hesperian lowland unit (lHl). This deposit is typically bounded by raised lobate margins. In addition, some margins have associated rille channels, which could have been produced sub-aerially by the back-wash of high-energy <span class="hlt">tsunami</span> <span class="hlt">waves</span>. Radar-sounding data indicate that the deposit is ice-rich. However, until now, the lack of <span class="hlt">wave</span>-cut shoreline features and the presence of lobate margins have remained an im-pediment to the acceptance of the paleo-ocean hypothesis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EOSTr..94R.297L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EOSTr..94R.297L"><span>Landslides Cause <span class="hlt">Tsunami</span> <span class="hlt">Waves</span>: Insights From Aysén Fjord, Chile</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lastras, Galderic; Amblas, David; Calafat, Antoni M.; Canals, Miquel; Frigola, Jaime; Hermanns, Reginald L.; Lafuerza, Sara; Longva, Oddvar; Micallef, Aaron; Sepúlveda, Sergio A.; Vargas, Gabriel; Batist, Marc De; Daele, Maarten Van; Azpiroz, María.; Bascuñán, Ignacio; Duhart, Paul; Iglesias, Olaia; Kempf, Philipp; Rayo, Xavier</p> <p>2013-08-01</p> <p>On 21 April 2007, an Mw 6.2 earthquake produced an unforeseen chain of events in the Aysén fjord (Chilean Patagonia, 45.5°S). The earthquake triggered hundreds of subaerial landslides along the fjord flanks. Some of the landslides eventually involved a subaqueous component that, in turn, generated a series of displacement waves—<span class="hlt">tsunami</span>-like <span class="hlt">waves</span> produced by the fast entry of a subaerial landmass into a water body—within the fjord [Naranjo et al., 2009; Sepúlveda and Serey, 2009; Hermanns et al., 2013]. These <span class="hlt">waves</span>, with run-ups several meters high along the shoreline, caused 10 fatalities. In addition, they severely damaged salmon farms, which constitute the main economic activity in the region, setting free millions of cultivated salmon with still unknown ecological consequences.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003PhDT.......225H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003PhDT.......225H"><span>Rayleigh <span class="hlt">wave</span> acoustic emission during crack <span class="hlt">propagation</span> in steel</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Horne, Michael R.</p> <p>2003-07-01</p> <p>An investigation was conducted of the existence of seismic surface pulses (SSP) on crack faces in near-failure fatigue. An SSP has components of various modes of <span class="hlt">wave</span> <span class="hlt">propagation</span>. The component with the largest amplitude is a Rayleigh surface <span class="hlt">wave</span> pulse. The possibility that these surface modes have much higher amplitudes than bulk modes of acoustic emission (AE) was illustrated by an idealized thought experiment relating an SSP on a half-space to the response of crack faces to crack extension. A number of aspects of AE monitoring in finite objects were investigated. Attributes of surface <span class="hlt">wave</span> <span class="hlt">propagation</span> on the edge of a specimen were found to be easier to monitor than other modes of <span class="hlt">wave</span> <span class="hlt">propagation</span>. Wavelet analysis was used to compare the characteristics of brittle AE with other sources. A new testing paradigm was developed to reduce interference from secondary sources of AE and enhance the investigation of AE from critical crack behavior. Unique specimen design features were developed, data acquisition features sought and validated, a dead weight load frame was modified, and data analysis procedures were developed. Criteria based on velocity, frequency content, amplitude and shape were devised to determine if an AE event is an SSP. The tests were designed to mimic load conditions on structures such as bridges and hence investigate the difference between AE generated in field conditions and that of typical laboratory conditions. Varieties of steel, from very ductile to very brittle, were tested. It was concluded that plastic zone formation, considered a secondary source of AE, was found not to interfere with the SSP activity. The SSP was found experimentally to have 2-3 times the amplitude of the bulk <span class="hlt">wave</span> AE. The lack of sufficient AE did not allow for determination of conclusive changes in the AE as the specimens approached failure. However, it was found that brittle crack extension in fatigue and ductile failure can produce <span class="hlt">wave</span> <span class="hlt">propagation</span> resembling the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhDT.......156H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhDT.......156H"><span>Rayleigh <span class="hlt">wave</span> acoustic emission during crack <span class="hlt">propagation</span> in steel</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Horne, Michael R.</p> <p></p> <p>An investigation was conducted of the existence of seismic surface pulses (SSP) on crack faces in near-failure fatigue. An SSP has components of various modes of <span class="hlt">wave</span> <span class="hlt">propagation</span>. The component with the largest amplitude is a Rayleigh surface <span class="hlt">wave</span> pulse. The possibility that these surface modes have much higher amplitudes than bulk modes of acoustic emission (AE) was illustrated by an idealized thought experiment relating an SSP on a half-space to the response of crack faces to crack extension. A number of aspects of AE monitoring in finite objects were investigated. Attributes of surface <span class="hlt">wave</span> <span class="hlt">propagation</span> on the edge of a specimen were found to be easier to monitor than other modes of <span class="hlt">wave</span> <span class="hlt">propagation</span>. Wavelet analysis was used to compare the characteristics of brittle AE with other sources. A new testing paradigm was developed to reduce interference from secondary sources of AE and enhance the investigation of AE from critical crack behavior. Unique specimen design features were developed, data acquisition features sought and validated, a dead weight load frame was modified, and data analysis procedures were developed. Criteria based on velocity, frequency content, amplitude and shape were devised to determine if an AE event is an SSP. The tests were designed to mimic load conditions on structures such as bridges and hence investigate the difference between AE generated in field conditions and that of typical laboratory conditions. Varieties of steel, from very ductile to very brittle, were tested. It was concluded that plastic zone formation, considered a secondary source of AE, was found not to interfere with the SSP activity. The SSP was found experimentally to have 2-3 times the amplitude of the bulk <span class="hlt">wave</span> AE. The lack of sufficient AE did not allow for determination of conclusive changes in the AE as the specimens approached failure. However, it was found that brittle crack extension in fatigue and ductile failure can produce <span class="hlt">wave</span> <span class="hlt">propagation</span> resembling the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhRvA..97a3824A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhRvA..97a3824A"><span>Modal analysis of <span class="hlt">wave</span> <span class="hlt">propagation</span> in dispersive media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abdelrahman, M. Ismail; Gralak, B.</p> <p>2018-01-01</p> <p>Surveys on <span class="hlt">wave</span> <span class="hlt">propagation</span> in dispersive media have been limited since the pioneering work of Sommerfeld [Ann. Phys. 349, 177 (1914), 10.1002/andp.19143491002] by the presence of branches in the integral expression of the <span class="hlt">wave</span> function. In this article a method is proposed to eliminate these critical branches and hence to establish a modal expansion of the time-dependent <span class="hlt">wave</span> function. The different components of the transient <span class="hlt">waves</span> are physically interpreted as the contributions of distinct sets of modes and characterized accordingly. Then, the modal expansion is used to derive a modified analytical expression of the Sommerfeld precursor improving significantly the description of the amplitude and the oscillating period up to the arrival of the Brillouin precursor. The proposed method and results apply to all <span class="hlt">waves</span> governed by the Helmholtz equations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PApGe.174.2961Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PApGe.174.2961Z"><span>The 2011 Tohoku <span class="hlt">Tsunami</span> on the Coast of Mexico: A Case Study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zaytsev, Oleg; Rabinovich, Alexander B.; Thomson, Richard E.</p> <p>2017-08-01</p> <p>The Tohoku (East Japan) earthquake of 11 March 2011 ( M w 9.0) generated a great trans-oceanic <span class="hlt">tsunami</span> that spread throughout the Pacific Ocean, where it was measured by numerous coastal tide gauges and open-ocean DART (Deep-ocean Assessment and Reporting of <span class="hlt">Tsunamis</span>) stations. Statistical and spectral analyses of the <span class="hlt">tsunami</span> <span class="hlt">waves</span> recorded along the Pacific coast of Mexico have enabled us to estimate the principal parameters of the <span class="hlt">waves</span> along the coast and to compare statistical features of the <span class="hlt">tsunami</span> with other <span class="hlt">tsunamis</span> recorded on this coast. We identify coastal "hot spots"—Manzanillo, Zihuatanejo, Acapulco, and Ensenada—corresponding to sites having highest <span class="hlt">tsunami</span> hazard potential, where <span class="hlt">wave</span> heights during the 2011 event exceeded 1.5-2 m and <span class="hlt">tsunami</span>-induced currents were strong enough to close port operations. Based on a joint spectral analysis of the <span class="hlt">tsunamis</span> and background noise, we reconstructed the spectra of <span class="hlt">tsunami</span> <span class="hlt">waves</span> in the deep ocean and found that, with the exception of the high-frequency spectral band (>5 cph), the spectra are in close agreement with the "true" <span class="hlt">tsunami</span> spectra determined from DART bottom pressure records. The departure of the high-frequency spectra in the coastal region from the deep-sea spectra is shown to be related to background infragravity <span class="hlt">waves</span> generated in the coastal zone. The total energy and frequency content of the Tohoku <span class="hlt">tsunami</span> is compared with the corresponding results for the 2010 Chilean <span class="hlt">tsunami</span>. Our findings show that the integral open-ocean <span class="hlt">tsunami</span> energy, I 0, was 2.30 cm2, or approximately 1.7 times larger than for the 2010 event. Comparison of this parameter with the mean coastal <span class="hlt">tsunami</span> variance (451 cm2) indicates that <span class="hlt">tsunami</span> <span class="hlt">waves</span> <span class="hlt">propagating</span> onshore from the open ocean amplified by 14 times; the same was observed for the 2010 <span class="hlt">tsunami</span>. The "<span class="hlt">tsunami</span> colour" (frequency content) for the 2011 Tohoku <span class="hlt">tsunami</span> was "red", with about 65% of the total energy associated with low-frequency <span class="hlt">waves</span> at frequencies</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26093439','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26093439"><span>Conversion of evanescent Lamb <span class="hlt">waves</span> into <span class="hlt">propagating</span> <span class="hlt">waves</span> via a narrow aperture edge.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yan, Xiang; Yuan, Fuh-Gwo</p> <p>2015-06-01</p> <p>This paper presents a quantitative study of conversion of evanescent Lamb <span class="hlt">waves</span> into <span class="hlt">propagating</span> in isotropic plates. The conversion is substantiated by prescribing time-harmonic Lamb displacements/tractions through a narrow aperture at an edge of a semi-infinite plate. Complex-valued dispersion and group velocity curves are employed to characterize the conversion process. The amplitude coefficient of the <span class="hlt">propagating</span> Lamb modes converted from evanescent is quantified based on the complex reciprocity theorem via a finite element analysis. The power flow generated into the plate can be separated into radiative and reactive parts made on the basis of <span class="hlt">propagating</span> and evanescent Lamb <span class="hlt">waves</span>, where <span class="hlt">propagating</span> Lamb <span class="hlt">waves</span> are theoretically proved to radiate pure real power flow, and evanescent Lamb <span class="hlt">waves</span> carry reactive pure imaginary power flow. The <span class="hlt">propagating</span> power conversion efficiency is then defined to quantitatively describe the conversion. The conversion efficiency is strongly frequency dependent and can be significant. With the converted <span class="hlt">propagating</span> <span class="hlt">waves</span> from evanescent, sensors at far-field can recapture some localized damage information that is generally possessed in evanescent <span class="hlt">waves</span> and may have potential application in structural health monitoring.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18002156','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18002156"><span>A two dimension model of the uterine electrical <span class="hlt">wave</span> <span class="hlt">propagation</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rihana, S; Lefrançois, E; Marque, C</p> <p>2007-01-01</p> <p>The uterus, usually quiescent during pregnancy, exhibits forceful contractions at term leading to delivery. These contractions are caused by the synchronized <span class="hlt">propagation</span> of electrical <span class="hlt">waves</span> from the pacemaker cells to its neighbors inducing the whole coordinated contraction of the uterus wall leading to labor. In a previous work, we simulate the electrical activity of a single uterine cell by a set of ordinary differential equations. Then, this model has been used to simulate the electrical activity <span class="hlt">propagation</span>. In the present work, the uterine cell tissue is assumed to have uniform and isotropic <span class="hlt">propagation</span>, and constant electrical membrane properties. The stability of the numerical solution imposes the choice of a critical temporal step. A <span class="hlt">wave</span> starts at a pacemaker cell; this electrical activity is initiated by the injection of an external stimulation current to the cell membrane. We observe synchronous <span class="hlt">wave</span> <span class="hlt">propagation</span> for axial resistance values around 0.5 GOmega or less and propoagation blocking for values greater than 0.7 GOmega. We compute the conduction velocity of the excitation, for different axial resistance values, and obtain a velocity about 10 cm/sec, approaching the one described by the literature for the rat at end of term.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70031605','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70031605"><span>Generation and <span class="hlt">propagation</span> of nonlinear internal <span class="hlt">waves</span> in Massachusetts Bay</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Scotti, A.; Beardsley, R.C.; Butman, B.</p> <p>2007-01-01</p> <p>During the summer, nonlinear internal <span class="hlt">waves</span> (NLIWs) are commonly observed <span class="hlt">propagating</span> in Massachusetts Bay. The topography of the area is unique in the sense that the generation area (over Stellwagen Bank) is only 25 km away from the shoaling area, and thus it represents an excellent natural laboratory to study the life cycle of NLIWs. To assist in the interpretation of the data collected during the 1998 Massachusetts Bay Internal <span class="hlt">Wave</span> Experiment (MBIWE98), a fully nonlinear and nonhydrostatic model covering the generation/shoaling region was developed, to investigate the response of the system to the range of background and driving conditions observed. Simplified models were also used to elucidate the role of nonlinearity and dispersion in shaping the NLIW field. This paper concentrates on the generation process and the subsequent evolution in the basin. The model was found to reproduce well the range of <span class="hlt">propagation</span> characteristics observed (arrival time, <span class="hlt">propagation</span> speed, amplitude), and provided a coherent framework to interpret the observations. Comparison with a fully nonlinear hydrostatic model shows that during the generation and initial evolution of the <span class="hlt">waves</span> as they move away from Stellwagen Bank, dispersive effects play a negligible role. Thus the problem can be well understood considering the geometry of the characteristics along which the Riemann invariants of the hydrostatic problem <span class="hlt">propagate</span>. Dispersion plays a role only during the evolution of the undular bore in the middle of Stellwagen Basin. The consequences for modeling NLIWs within hydrostatic models are briefly discussed at the end.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21567649-spatial-damping-propagating-kink-waves-prominence-threads','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21567649-spatial-damping-propagating-kink-waves-prominence-threads"><span>SPATIAL DAMPING OF <span class="hlt">PROPAGATING</span> KINK <span class="hlt">WAVES</span> IN PROMINENCE THREADS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Soler, R.; Oliver, R.; Ballester, J. L., E-mail: roberto.soler@wis.kuleuven.be</p> <p></p> <p>Transverse oscillations and <span class="hlt">propagating</span> <span class="hlt">waves</span> are frequently observed in threads of solar prominences/filaments and have been interpreted as kink magnetohydrodynamic (MHD) modes. We investigate the spatial damping of <span class="hlt">propagating</span> kink MHD <span class="hlt">waves</span> in transversely nonuniform and partially ionized prominence threads. Resonant absorption and ion-neutral collisions (Cowling's diffusion) are the damping mechanisms taken into account. The dispersion relation of resonant kink <span class="hlt">waves</span> in a partially ionized magnetic flux tube is numerically solved by considering prominence conditions. Analytical expressions of the wavelength and damping length as functions of the kink mode frequency are obtained in the thin tube and thin boundary approximations.more » For typically reported periods of thread oscillations, resonant absorption is an efficient mechanism for the kink mode spatial damping, while ion-neutral collisions have a minor role. Cowling's diffusion dominates both the <span class="hlt">propagation</span> and damping for periods much shorter than those observed. Resonant absorption may explain the observed spatial damping of kink <span class="hlt">waves</span> in prominence threads. The transverse inhomogeneity length scale of the threads can be estimated by comparing the observed wavelengths and damping lengths with the theoretically predicted values. However, the ignorance of the form of the density profile in the transversely nonuniform layer introduces inaccuracies in the determination of the inhomogeneity length scale.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..DPPT11056V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..DPPT11056V"><span><span class="hlt">Propagation</span> of radio frequency <span class="hlt">waves</span> through density fluctuations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Valvis, S. I.; Papagiannis, P.; Papadopoulos, A.; Hizanidis, K.; Glytsis, E.; Bairaktaris, F.; Zisis, A.; Tigelis, I.; Ram, A. K.</p> <p>2017-10-01</p> <p>On their way to the core of a tokamak plasma, radio frequency (RF) <span class="hlt">waves</span>, excited in the vacuum region, have to <span class="hlt">propagate</span> through a variety of density fluctuations in the edge region. These fluctuations include coherent structures, like blobs that can be field aligned or not, as well as turbulent and filamentary structures. We have been studying the effect of fluctuations on RF <span class="hlt">propagation</span> using both theoretical (analytical) and computational models. The theoretical results are being compared with those obtained by two different numerical codes ``a Finite Difference Frequency Domain code and the commercial COMSOL package. For plasmas with arbitrary distribution of coherent and turbulent fluctuations, we have formulated an effective dielectric permittivity of the edge plasma. This permittivity tensor is then used in numerical simulations to study the effect of multi-scale turbulence on RF <span class="hlt">waves</span>. We not only consider plane <span class="hlt">waves</span> but also Gaussian beams in the electron cyclotron and lower hybrid range of frequencies. The analytical theory and results from simulations on the <span class="hlt">propagation</span> of RF <span class="hlt">waves</span> will be presented. Supported in part by the Hellenic National Programme on Controlled Thermonuclear Fusion associated with the EUROfusion Consortium and by DoE Grant DE-FG02-91ER-54109.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://rosap.ntl.bts.gov/view/dot/14682','DOTNTL'); return false;" href="https://rosap.ntl.bts.gov/view/dot/14682"><span>An introduction to <span class="hlt">wave</span> <span class="hlt">propagation</span> in pavements and soils : theory and practice</span></a></p> <p><a target="_blank" href="http://ntlsearch.bts.gov/tris/index.do">DOT National Transportation Integrated Search</a></p> <p></p> <p>1999-02-01</p> <p>This paper introduces the physics and analyst of <span class="hlt">wave</span> <span class="hlt">propagation</span> in pavement and soils. The study of <span class="hlt">wave</span> <span class="hlt">propagation</span> in soils can yield useful results to engineers concerned with resilient characteristics of a particular site, dynamic soils structu...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1210998Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1210998Z"><span>Modeling of influence from remote <span class="hlt">tsunami</span> at the coast of Sakhalin and Kuriles islands.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zaytsev, Andrey; Pelinovsky, Efim; Yalciner, Ahmet; Chernov, Anton; Kostenko, Irina</p> <p>2010-05-01</p> <p>The Far East coast of Russia (Kuriles islands, Sakhalin, Kamchatka) is the area where the dangerous natural phenomena as <span class="hlt">tsunami</span> is located. A lot of works are established for decreasing of <span class="hlt">tsunami</span>'s influence. <span class="hlt">Tsunami</span> mapping and mitigation strategy are given for some regions. The centers of <span class="hlt">Tsunami</span> Warning System are opened, enough plenty of records of a <span class="hlt">tsunami</span> are collected. The properties of local <span class="hlt">tsunami</span> are studied well. At the same time, the catastrophic event of the Indonesian <span class="hlt">tsunami</span>, which had happened in December, 2004, when the sufficient <span class="hlt">waves</span> have reached the coasts of Africa and South America, it is necessary to note, that the coats, which was far from the epicenter of earthquakes can be effected by catastrophic influence. Moreover, it is practically unique case, when using <span class="hlt">Tsunami</span> Warning System can reduce the number of human victims to zero. Development of the computer technologies, numerical methods for the solution of systems of the nonlinear differential equations makes computer modeling real and hypothetical <span class="hlt">tsunamis</span> is the basic method of studying features of distribution of <span class="hlt">waves</span> in water areas and their influence at coast. Numerical modeling of distribution of historical <span class="hlt">tsunami</span> from the seismic sources in the Pacific Ocean was observed. The events with an epicenter, remote from Far East coast of Russia were considered. The estimation of the remote <span class="hlt">tsunami</span> <span class="hlt">waves</span> <span class="hlt">propagation</span> was developed. Impact force of <span class="hlt">tsunamis</span> was estimated. The features of passage of <span class="hlt">tsunami</span> through Kuril Straits were considered. The spectral analysis of records in settlements of Sakhalin and Kuriles is lead. NAMI-DANCE program was used for <span class="hlt">tsunami</span> <span class="hlt">propagation</span> numerical modeling. It is used finite element numerical schemes for Shallow Water Equations and Nonlinear-Dispersive Equations, with use Nested Grid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840007292','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840007292"><span>Asymptotic analysis of numerical <span class="hlt">wave</span> <span class="hlt">propagation</span> in finite difference equations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Giles, M.; Thompkins, W. T., Jr.</p> <p>1983-01-01</p> <p>An asymptotic technique is developed for analyzing the <span class="hlt">propagation</span> and dissipation of <span class="hlt">wave</span>-like solutions to finite difference equations. It is shown that for each fixed complex frequency there are usually several <span class="hlt">wave</span> solutions with different wavenumbers and the slowly varying amplitude of each satisfies an asymptotic amplitude equation which includes the effects of smoothly varying coefficients in the finite difference equations. The local group velocity appears in this equation as the velocity of convection of the amplitude. Asymptotic boundary conditions coupling the amplitudes of the different <span class="hlt">wave</span> solutions are also derived. A wavepacket theory is developed which predicts the motion, and interaction at boundaries, of wavepackets, <span class="hlt">wave</span>-like disturbances of finite length. Comparison with numerical experiments demonstrates the success and limitations of the theory. Finally an asymptotic global stability analysis is developed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSH21D2561G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSH21D2561G"><span>Obliquely <span class="hlt">Propagating</span> <span class="hlt">Waves</span> in Bi-Kappa Plasmas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gaelzer, R.; Ziebell, L. F.; Meneses, A. R.</p> <p>2016-12-01</p> <p>The effects of kappa velocity distribution functions (VDFs) have been the subjectof intense research. Such functions have beenfound to provide a better fitting to the VDFs measured by spacecraftin the solar wind. An anisotropic VDF contains free energy that can excite wavesin the plasma. The induced turbulence also determines the observed shape of the VDF.The general treatment for <span class="hlt">waves</span> excited by (bi-)Maxwellian plasmas is well-established.However, for kappa distributions (isotropic or anisotropic), the majority of the studieswere restricted to the limiting cases of purely parallel or perpendicular <span class="hlt">propagation</span>.Contributions to the general case of obliquely-<span class="hlt">propagating</span> <span class="hlt">waves</span> have been scarcely reported.The absence of a general treatment prevents a complete analysis of the <span class="hlt">wave</span>-particle interactionin kappa plasmas, since some instabilities can operate both in the parallel and oblique directions.A series of papers published by the authors begin to remedy this situation. In a first work [1],we have obtained the dielectric tensor and dispersion relations for quasi-perpendicular dispersive Alfvén <span class="hlt">waves</span> resulting from a kappa VDF. This approach was later generalized by [2],where the formalism was extended to the general case of electrostatic/electromagnetic <span class="hlt">waves</span> propagatingin an isotropic kappa plasma in any frequency range and for arbitrary angles.In the present work [3], we generalize even further the formalism by the derivation of thegeneral dielectric tensor of an anisotropic bi-kappa plasma. We present the state-of-the-art of theformalism and show how it enables a systematic study of <span class="hlt">waves</span> and instabilities <span class="hlt">propagating</span> inarbitrary directions and frequencies in a bi-kappa plasma.[1] R. Gaelzer, L. F. Ziebell, J. Geophys. Res. 119, 9334 (2014), doi: 10.1002/2014JA020667.[2] R. Gaelzer, L. F. Ziebell, Phys. Plasmas 23, 022110 (2016), doi: 10.1063/1.4941260.[3] R. Gaelzer et al., Phys. Plasmas 23, 062108 (2016), doi: 10.1063/1.4953430.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012RMRE...45..901P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012RMRE...45..901P"><span><span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Discontinuous Media by the Scattering Matrix Method</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Perino, A.; Orta, R.; Barla, G.</p> <p>2012-09-01</p> <p><span class="hlt">Propagation</span> of elastic <span class="hlt">waves</span> in discontinuous media is studied in this paper by the scattering matrix method (SMM). An electromagnetic transmission line analogy is also used to set up the mathematical model. The SMM operates in the frequency domain and allows for all <span class="hlt">wave</span> polarizations (P, SV and SH). Rock masses are examples of discontinuous media in which the discontinuities (fractures or joints) influence <span class="hlt">wave</span> <span class="hlt">propagation</span>. Both elastic and viscoelastic joints are considered and the latter are described by Kelvin-Voigt, Maxwell and Burgers models. Rock joints with Coulomb slip behavior are also analyzed, by applying the averaging principle of Caughy (J Appl Mech 27:640-643, 1960). The evaluation of the effects of periodic discontinuities in a homogeneous medium is presented by introducing the concept of Bloch <span class="hlt">waves</span>. The dispersion curves of these <span class="hlt">waves</span> are useful to explain the existence of frequency bands of strong attenuation, also in the case of lossless (perfectly elastic) structures. Simple expressions of transmission and reflection coefficients are obtained. Finally, the SMM results are compared with those computed via the distinct element method (DEM). The comparisons are performed on a medium with joints with Coulomb slip behavior and the agreement is satisfactory, although the SMM must be applied in conjunction with the equivalent linearization technique. Even if the DEM is much more general, the SMM in these simple cases is extremely faster and provides a higher physical insight.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JSeis..18...61S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JSeis..18...61S"><span><span class="hlt">Propagation</span> and attenuation of Rayleigh <span class="hlt">waves</span> in generalized thermoelastic media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sharma, M. D.</p> <p>2014-01-01</p> <p>This study considers the <span class="hlt">propagation</span> of Rayleigh <span class="hlt">waves</span> in a generalized thermoelastic half-space with stress-free plane boundary. The boundary has the option of being either isothermal or thermally insulated. In either case, the dispersion equation is obtained in the form of a complex irrational expression due to the presence of radicals. This dispersion equation is rationalized into a polynomial equation, which is solvable, numerically, for exact complex roots. The roots of the dispersion equation are obtained after removing the extraneous zeros of this polynomial equation. Then, these roots are filtered out for the inhomogeneous <span class="hlt">propagation</span> of <span class="hlt">waves</span> decaying with depth. Numerical examples are solved to analyze the effects of thermal properties of elastic materials on the dispersion of existing surface <span class="hlt">waves</span>. For these thermoelastic Rayleigh <span class="hlt">waves</span>, the behavior of elliptical particle motion is studied inside and at the surface of the medium. Insulation of boundary does play a significant role in changing the speed, amplitude, and polarization of Rayleigh <span class="hlt">waves</span> in thermoelastic media.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19750054178&hterms=chemical+equilibrium&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dchemical%2Bequilibrium','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19750054178&hterms=chemical+equilibrium&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dchemical%2Bequilibrium"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in a quasi-chemical equilibrium plasma</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fang, T.-M.; Baum, H. R.</p> <p>1975-01-01</p> <p><span class="hlt">Wave</span> <span class="hlt">propagation</span> in a quasi-chemical equilibrium plasma is studied. The plasma is infinite and without external fields. The chemical reactions are assumed to result from the ionization and recombination processes. When the gas is near equilibrium, the dominant role describing the evolution of a reacting plasma is played by the global conservation equations. These equations are first derived and then used to study the small amplitude <span class="hlt">wave</span> motion for a near-equilibrium situation. Nontrivial damping effects have been obtained by including the conduction current terms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800002736','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800002736"><span><span class="hlt">Propagation</span> of <span class="hlt">waves</span> in a medium with high radiation pressure</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bisnovatyy-Kogan, G. S.; Blinnikov, S. I.</p> <p>1979-01-01</p> <p>The <span class="hlt">propagation</span> and mutual transformation of acoustic and thermal <span class="hlt">waves</span> are investigated in media with a high radiative pressure. The equations of hydrodynamics for matter and the radiative transfer equations in a moving medium in the Eddington approximation are used in the investigation. Model problems of <span class="hlt">waves</span> in a homogeneous medium with an abrupt jump in opacity and in a medium of variable opacity are presented. The characteristic and the times of variability are discussed. Amplitude for the brightness fluctuations for very massive stars are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSA21A2351B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSA21A2351B"><span>VLF Radio <span class="hlt">Wave</span> <span class="hlt">Propagation</span> Across the Day/Night Terminator</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burch, H.; Moore, R. C.</p> <p>2016-12-01</p> <p>In May 2016, a new array of VLF radio receivers was deployed spanning the East Coast of the United States. We present preliminary observations from the array, which was designed in part to track the <span class="hlt">propagation</span> of the narrowband VLF transmitter signal, NAA (24.0 kHz), down the coast from Cutler, Maine. Amplitude, phase, and polarization observations are compared over multiple days and at different times of year to investigate the dependence of VLF <span class="hlt">propagation</span> characteristics on solar zenith angle. Measurements are compared to simulations using the Long <span class="hlt">Wave</span> <span class="hlt">Propagation</span> Capability code (LWPC) in order to evaluate the accuracy of LWPC's built-in ionosphere model. Efforts to improve the ionosphere model based on observations are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22492647-numerical-modelling-nonlinear-full-wave-acoustic-propagation','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22492647-numerical-modelling-nonlinear-full-wave-acoustic-propagation"><span>Numerical modelling of nonlinear full-<span class="hlt">wave</span> acoustic <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Velasco-Segura, Roberto, E-mail: roberto.velasco@ccadet.unam.mx; Rendón, Pablo L., E-mail: pablo.rendon@ccadet.unam.mx</p> <p>2015-10-28</p> <p>The various model equations of nonlinear acoustics are arrived at by making assumptions which permit the observation of the interaction with <span class="hlt">propagation</span> of either single or joint effects. We present here a form of the conservation equations of fluid dynamics which are deduced using slightly less restrictive hypothesis than those necessary to obtain the well known Westervelt equation. This formulation accounts for full <span class="hlt">wave</span> diffraction, nonlinearity, and thermoviscous dissipative effects. A two-dimensional, finite-volume method using Roe’s linearisation has been implemented to obtain numerically the solution of the proposed equations. This code, which has been written for parallel execution on amore » GPU, can be used to describe moderate nonlinear phenomena, at low Mach numbers, in domains as large as 100 <span class="hlt">wave</span> lengths. Applications range from models of diagnostic and therapeutic HIFU, to parametric acoustic arrays and nonlinear <span class="hlt">propagation</span> in acoustic waveguides. Examples related to these applications are shown and discussed.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JSV...425..170F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JSV...425..170F"><span>Singular boundary method for <span class="hlt">wave</span> <span class="hlt">propagation</span> analysis in periodic structures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fu, Zhuojia; Chen, Wen; Wen, Pihua; Zhang, Chuanzeng</p> <p>2018-07-01</p> <p>A strong-form boundary collocation method, the singular boundary method (SBM), is developed in this paper for the <span class="hlt">wave</span> <span class="hlt">propagation</span> analysis at low and moderate wavenumbers in periodic structures. The SBM is of several advantages including mathematically simple, easy-to-program, meshless with the application of the concept of origin intensity factors in order to eliminate the singularity of the fundamental solutions and avoid the numerical evaluation of the singular integrals in the boundary element method. Due to the periodic behaviors of the structures, the SBM coefficient matrix can be represented as a block Toeplitz matrix. By employing three different fast Toeplitz-matrix solvers, the computational time and storage requirements are significantly reduced in the proposed SBM analysis. To demonstrate the effectiveness of the proposed SBM formulation for <span class="hlt">wave</span> <span class="hlt">propagation</span> analysis in periodic structures, several benchmark examples are presented and discussed The proposed SBM results are compared with the analytical solutions, the reference results and the COMSOL software.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018WRCM...28..215E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018WRCM...28..215E"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in embedded inhomogeneous nanoscale plates incorporating thermal effects</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ebrahimi, Farzad; Barati, Mohammad Reza; Dabbagh, Ali</p> <p>2018-04-01</p> <p>In this article, an analytical approach is developed to study the effects of thermal loading on the <span class="hlt">wave</span> <span class="hlt">propagation</span> characteristics of an embedded functionally graded (FG) nanoplate based on refined four-variable plate theory. The heat conduction equation is solved to derive the nonlinear temperature distribution across the thickness. Temperature-dependent material properties of nanoplate are graded using Mori-Tanaka model. The nonlocal elasticity theory of Eringen is introduced to consider small-scale effects. The governing equations are derived by the means of Hamilton's principle. Obtained frequencies are validated with those of previously published works. Effects of different parameters such as temperature distribution, foundation parameters, nonlocal parameter, and gradient index on the <span class="hlt">wave</span> <span class="hlt">propagation</span> response of size-dependent FG nanoplates have been investigated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMOS43D1341B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMOS43D1341B"><span>Near Source 2007 Peru <span class="hlt">Tsunami</span> Runup Observations and Modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borrero, J. C.; Fritz, H. M.; Kalligeris, N.; Broncano, P.; Ortega, E.</p> <p>2008-12-01</p> <p>On 15 August 2007 an earthquake with moment magnitude (Mw) of 8.0 centered off the coast of central Peru, generated a <span class="hlt">tsunami</span> with locally focused runup heights of up to 10 m. A reconnaissance team was deployed two weeks after the event and investigated the <span class="hlt">tsunami</span> effects at 51 sites. Three <span class="hlt">tsunami</span> fatalities were reported south of the Paracas Peninsula in a sparsely populated desert area where the largest <span class="hlt">tsunami</span> runup heights and massive inundation distances up to 2 km were measured. Numerical modeling of the earthquake source and <span class="hlt">tsunami</span> suggest that a region of high slip near the coastline was primarily responsible for the extreme runup heights. The town of Pisco was spared by the Paracas Peninsula, which blocked <span class="hlt">tsunami</span> <span class="hlt">waves</span> from <span class="hlt">propagating</span> northward from the high slip region. As with all near field <span class="hlt">tsunamis</span>, the <span class="hlt">waves</span> struck within minutes of the massive ground shaking. Spontaneous evacuations coordinated by the Peruvian Coast Guard minimized the fatalities and illustrate the importance of community-based education and awareness programs. The residents of the fishing village Lagunilla were unaware of the <span class="hlt">tsunami</span> hazard after an earthquake and did not evacuate, which resulted in 3 fatalities. Despite the relatively benign <span class="hlt">tsunami</span> effects at Pisco from this event, the <span class="hlt">tsunami</span> hazard for this city (and its liquefied natural gas terminal) cannot be underestimated. Between 1687 and 1868, the city of Pisco was destroyed 4 times by <span class="hlt">tsunami</span> <span class="hlt">waves</span>. Since then, two events (1974 and 2007) have resulted in partial inundation and moderate damage. The fact that potentially devastating <span class="hlt">tsunami</span> runup heights were observed immediately south of the peninsula only serves to underscore this point.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12765363','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12765363"><span>Antiplane shear <span class="hlt">wave</span> <span class="hlt">propagation</span> in fiber-reinforced composites.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kim, Jin-Yeon</p> <p>2003-05-01</p> <p>A self-consistent method for analyzing antiplane shear <span class="hlt">wave</span> <span class="hlt">propagation</span> in two-dimensional inhomogeneous media is presented. For applications in the high-frequency range, the self-consistent condition for the effective medium is solved being supplemented with the theory of quasidynamic effective density. Comparisons with other theoretical calculations and experimental data for fiber-reinforced composites demonstrate the merits of using the present method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910006535','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910006535"><span>Monograph on <span class="hlt">propagation</span> of sound <span class="hlt">waves</span> in curved ducts</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rostafinski, Wojciech</p> <p>1991-01-01</p> <p>After reviewing and evaluating the existing material on sound <span class="hlt">propagation</span> in curved ducts without flow, it seems strange that, except for Lord Rayleigh in 1878, no book on acoustics has treated the case of <span class="hlt">wave</span> motion in bends. This monograph reviews the available analytical and experimental material, nearly 30 papers published on this subject so far, and concisely summarizes what has been learned about the motion of sound in hard-wall and acoustically lined cylindrical bends.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA559771','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA559771"><span>Acoustoelastic Lamb <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Biaxially Stressed Plates (Preprint)</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2012-03-01</p> <p>0188 The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing...control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1 . REPORT DATE (DD-MM-YY) 2. REPORT TYPE 3. DATES COVERED (From - To) March 2012...Journal Article 1 March 2012 – 1 March 2012 4. TITLE AND SUBTITLE ACOUSTOELASTIC LAMB <span class="hlt">WAVE</span> <span class="hlt">PROPAGATION</span> IN BIAXIALLY STRESSED PLATES (PREPRINT</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AIPC.1949g0002H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AIPC.1949g0002H"><span>Directional nonlinear guided <span class="hlt">wave</span> mixing: Case study of counter-<span class="hlt">propagating</span> shear horizontal <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hasanian, Mostafa; Lissenden, Cliff J.</p> <p>2018-04-01</p> <p>While much nonlinear ultrasonics research has been conducted on higher harmonic generation, <span class="hlt">wave</span> mixing provides the potential for sensitive measurements of incipient damage unencumbered by instrumentation nonlinearity. Studies of nonlinear ultrasonic <span class="hlt">wave</span> mixing, both collinear and noncollinear, for bulk <span class="hlt">waves</span> have shown the robust capability of <span class="hlt">wave</span> mixing for early damage detection. One merit of bulk <span class="hlt">wave</span> mixing lies in their non-dispersive nature, but guided <span class="hlt">waves</span> enable inspection of otherwise inaccessible material and a variety of mixing options. Co-directional guided <span class="hlt">wave</span> mixing was studied previously, but arbitrary direction guided <span class="hlt">wave</span> mixing has not been addressed until recently. <span class="hlt">Wave</span> vector analysis is applied to study variable mixing angles to find <span class="hlt">wave</span> mode triplets (two primary <span class="hlt">waves</span> and a secondary <span class="hlt">wave</span>) resulting in the phase matching condition. As a case study, counter-<span class="hlt">propagating</span> Shear Horizontal (SH) guided <span class="hlt">wave</span> mixing is analyzed. SH <span class="hlt">wave</span> interactions generate a secondary Lamb <span class="hlt">wave</span> mode that is readily receivable. Reception of the secondary Lamb <span class="hlt">wave</span> mode is compared for an angle beam transducer, an air coupled transducer, and a laser Doppler vibrometer (LDV). Results from the angle beam and air coupled transducers are quite consistent, while the LDV measurement is plagued by variability issues.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020039526','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020039526"><span>Radio <span class="hlt">Wave</span> <span class="hlt">Propagation</span> Handbook for Communication on and Around Mars</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ho, Christian; Golshan, Nasser; Kliore, Arvydas</p> <p>2002-01-01</p> <p>This handbook examines the effects of the Martian environment on radio <span class="hlt">wave</span> <span class="hlt">propagation</span> on Mars and in the space near the planet. The environmental effects include these from the Martian atmosphere, ionosphere, global dust storms, aerosols, clouds, and geomorphologic features. Relevant Martian environmental parameters were extracted from the measurements of Mars missions during the past 30 years, especially from Mars Pathfinder and Mars Global Surveyor. The results derived from measurements and analyses have been reviewed through an extensive literature search. The updated parameters have been theoretically analyzed to study their effects on radio <span class="hlt">propagation</span>. This handbook also provides basic information about the entire telecommunications environment on and around Mars for <span class="hlt">propagation</span> researchers, system engineers, and link analysts. Based on these original analyses, some important recommendations have been made, including the use of the Martian ionosphere as a reflector for Mars global or trans-horizon communication between future Martian colonies, reducing dust storm scattering effects, etc. These results have extended our <span class="hlt">wave</span> <span class="hlt">propagation</span> knowledge to a planet other than Earth; and the tables, models, and graphics included in this handbook will benefit telecommunication system engineers and scientific researchers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..MARE24002D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..MARE24002D"><span>Excitation of <span class="hlt">propagating</span> spin <span class="hlt">waves</span> by pure spin current</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Demokritov, Sergej</p> <p></p> <p>Recently it was demonstrated that pure spin currents can be utilized to excite coherent magnetization dynamics, which enables development of novel magnetic nano-oscillators. Such oscillators do not require electric current flow through the active magnetic layer, which can help to reduce the Joule power dissipation and electromigration. In addition, this allows one to use insulating magnetic materials and provides an unprecedented geometric flexibility. The pure spin currents can be produced by using the spin-Hall effect (SHE). However, SHE devices have a number of shortcomings. In particular, efficient spin Hall materials exhibit a high resistivity, resulting in the shunting of the driving current through the active magnetic layer and a significant Joule heating. These shortcomings can be eliminated in devices that utilize spin current generated by the nonlocal spin-injection (NLSI) mechanism. Here we review our recent studies of excitation of magnetization dynamics and <span class="hlt">propagating</span> spin <span class="hlt">waves</span> by using NLSI. We show that NLSI devices exhibit highly-coherent dynamics resulting in the oscillation linewidth of a few MHz at room temperature. Thanks to the geometrical flexibility of the NLSI oscillators, one can utilize dipolar fields in magnetic nano-patterns to convert current-induced localized oscillations into <span class="hlt">propagating</span> spin <span class="hlt">waves</span>. The demonstrated systems exhibit efficient and controllable excitation and directional <span class="hlt">propagation</span> of coherent spin <span class="hlt">waves</span> characterized by a large decay length. The obtained results open new perspectives for the future-generation electronics using electron spin degree of freedom for transmission and processing of information on the nanoscale.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNH52A..07E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNH52A..07E"><span><span class="hlt">Tsunami</span> Hazard Assessment: Source regions of concern to U.S. interests derived from NOAA <span class="hlt">Tsunami</span> Forecast Model Development</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Eble, M. C.; uslu, B. U.; Wright, L.</p> <p>2013-12-01</p> <p>Synthetic <span class="hlt">tsunamis</span> generated from source regions around the Pacific Basin are analyzed in terms of their relative impact on United States coastal locations.. The region of <span class="hlt">tsunami</span> origin is as important as the expected magnitude and the predicted inundation for understanding <span class="hlt">tsunami</span> hazard. The NOAA Center for <span class="hlt">Tsunami</span> Research has developed high-resolution <span class="hlt">tsunami</span> models capable of predicting <span class="hlt">tsunami</span> arrival time and amplitude of <span class="hlt">waves</span> at each location. These models have been used to conduct <span class="hlt">tsunami</span> hazard assessments to assess maximum impact and <span class="hlt">tsunami</span> inundation for use by local communities in education and evacuation map development. Hazard assessment studies conducted for Los Angeles, San Francisco, Crescent City, Hilo, and Apra Harbor are combined with results of <span class="hlt">tsunami</span> forecast model development at each of seventy-five locations. Complete hazard assessment, identifies every possible <span class="hlt">tsunami</span> variation from a pre-computed <span class="hlt">propagation</span> database. Study results indicate that the Eastern Aleutian Islands and Alaska are the most likely regions to produce the largest impact on the West Coast of the United States, while the East Philippines and Mariana trench regions impact Apra Harbor, Guam. Hawaii appears to be impacted equally from South America, Alaska and the Kuril Islands.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005WRR....4102025L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005WRR....4102025L"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> through elastic porous media containing two immiscible fluids</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lo, Wei-Cheng; Sposito, Garrison; Majer, Ernest</p> <p>2005-02-01</p> <p>Acoustic <span class="hlt">wave</span> phenomena in porous media containing multiphase fluids have received considerable attention in recent years because of an increasing scientific awareness of poroelastic behavior in groundwater aquifers. To improve quantitative understanding of these phenomena, a general set of coupled partial differential equations was derived to describe dilatational <span class="hlt">wave</span> <span class="hlt">propagation</span> through an elastic porous medium permeated by two immiscible fluids. These equations, from which previous models of dilatational <span class="hlt">wave</span> <span class="hlt">propagation</span> can be recovered as special cases, incorporate both inertial coupling and viscous drag in an Eulerian frame of reference. Two important poroelasticity concepts, the linearized increment of fluid content and the closure relation for porosity change, originally defined for an elastic porous medium containing a single fluid, also are generalized for a two-fluid system. To examine the impact of relative fluid saturation and <span class="hlt">wave</span> excitation frequency (50, 100, 150, and 200 Hz) on free dilatational <span class="hlt">wave</span> behavior in unconsolidated porous media, numerical simulations of the three possible modes of <span class="hlt">wave</span> motion were conducted for Columbia fine sandy loam containing either an air-water or oil-water mixture. The results showed that the <span class="hlt">propagating</span> (P1) mode, which results from in-phase motions of the solid framework and the two pore fluids, moves with a speed equal to the square root of the ratio of an effective bulk modulus to an effective density of the fluid-containing porous medium, regardless of fluid saturation and for both fluid mixtures. The nature of the pore fluids exerts a significant influence on the attenuation of the P1 <span class="hlt">wave</span>. In the air-water system, attenuation was controlled by material density differences and the relative mobilities of the pore fluids, whereas in the oil-water system an effective kinematic shear viscosity of the pore fluids was the controlling parameter. On the other hand, the speed and attenuation of the two diffusive</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...638041D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...638041D"><span>Low frequency piezoresonance defined dynamic control of terahertz <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dutta, Moumita; Betal, Soutik; Peralta, Xomalin G.; Bhalla, Amar S.; Guo, Ruyan</p> <p>2016-11-01</p> <p>Phase modulators are one of the key components of many applications in electromagnetic and opto-electric <span class="hlt">wave</span> <span class="hlt">propagations</span>. Phase-shifters play an integral role in communications, imaging and in coherent material excitations. In order to realize the terahertz (THz) electromagnetic spectrum as a fully-functional bandwidth, the development of a family of efficient THz phase modulators is needed. Although there have been quite a few attempts to implement THz phase modulators based on quantum-well structures, liquid crystals, or meta-materials, significantly improved sensitivity and dynamic control for phase modulation, as we believe can be enabled by piezoelectric-resonance devices, is yet to be investigated. In this article we provide an experimental demonstration of phase modulation of THz beam by operating a ferroelectric single crystal LiNbO3 film device at the piezo-resonance. The piezo-resonance, excited by an external a.c. electric field, develops a coupling between electromagnetic and lattice-<span class="hlt">wave</span> and this coupling governs the <span class="hlt">wave</span> <span class="hlt">propagation</span> of the incident THz beam by modulating its phase transfer function. We report the understanding developed in this work can facilitate the design and fabrication of a family of resonance-defined highly sensitive and extremely low energy sub-millimeter <span class="hlt">wave</span> sensors and modulators.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AIPC.1084...45M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AIPC.1084...45M"><span>A Kinetic Approach to <span class="hlt">Propagation</span> and Stability of Detonation <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Monaco, R.; Bianchi, M. Pandolfi; Soares, A. J.</p> <p>2008-12-01</p> <p>The problem of the steady <span class="hlt">propagation</span> and linear stability of a detonation <span class="hlt">wave</span> is formulated in the kinetic frame for a quaternary gas mixture in which a reversible bimolecular reaction takes place. The reactive Euler equations and related Rankine-Hugoniot conditions are deduced from the mesoscopic description of the process. The steady <span class="hlt">propagation</span> problem is solved for a Zeldovich, von Neuman and Doering (ZND) <span class="hlt">wave</span>, providing the detonation profiles and the <span class="hlt">wave</span> thickness for different overdrive degrees. The one-dimensional stability of such detonation <span class="hlt">wave</span> is then studied in terms of an initial value problem coupled with an acoustic radiation condition at the equilibrium final state. The stability equations and their initial data are deduced from the linearized reactive Euler equations and related Rankine-Hugoniot conditions through a normal mode analysis referred to the complex disturbances of the steady state variables. Some numerical simulations for an elementary reaction of the hydrogen-oxygen chain are proposed in order to describe the time and space evolution of the instabilities induced by the shock front perturbation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27901070','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27901070"><span>Low frequency piezoresonance defined dynamic control of terahertz <span class="hlt">wave</span> <span class="hlt">propagation</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dutta, Moumita; Betal, Soutik; Peralta, Xomalin G; Bhalla, Amar S; Guo, Ruyan</p> <p>2016-11-30</p> <p>Phase modulators are one of the key components of many applications in electromagnetic and opto-electric <span class="hlt">wave</span> <span class="hlt">propagations</span>. Phase-shifters play an integral role in communications, imaging and in coherent material excitations. In order to realize the terahertz (THz) electromagnetic spectrum as a fully-functional bandwidth, the development of a family of efficient THz phase modulators is needed. Although there have been quite a few attempts to implement THz phase modulators based on quantum-well structures, liquid crystals, or meta-materials, significantly improved sensitivity and dynamic control for phase modulation, as we believe can be enabled by piezoelectric-resonance devices, is yet to be investigated. In this article we provide an experimental demonstration of phase modulation of THz beam by operating a ferroelectric single crystal LiNbO 3 film device at the piezo-resonance. The piezo-resonance, excited by an external a.c. electric field, develops a coupling between electromagnetic and lattice-<span class="hlt">wave</span> and this coupling governs the <span class="hlt">wave</span> <span class="hlt">propagation</span> of the incident THz beam by modulating its phase transfer function. We report the understanding developed in this work can facilitate the design and fabrication of a family of resonance-defined highly sensitive and extremely low energy sub-millimeter <span class="hlt">wave</span> sensors and modulators.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PrOce.159..296R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PrOce.159..296R"><span>The <span class="hlt">tsunami</span> phenomenon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Röbke, B. R.; Vött, A.</p> <p>2017-12-01</p> <p>With human activity increasingly concentrating on coasts, <span class="hlt">tsunamis</span> (from Japanese tsu = harbour, nami = <span class="hlt">wave</span>) are a major natural hazard to today's society. Stimulated by disastrous <span class="hlt">tsunami</span> impacts in recent years, for instance in south-east Asia (2004) or in Japan (2011), <span class="hlt">tsunami</span> science has significantly flourished, which has brought great advances in hazard assessment and mitigation plans. Based on <span class="hlt">tsunami</span> research of the last decades, this paper provides a thorough treatise on the <span class="hlt">tsunami</span> phenomenon from a geoscientific point of view. Starting with the <span class="hlt">wave</span> features, <span class="hlt">tsunamis</span> are introduced as long shallow water <span class="hlt">waves</span> or <span class="hlt">wave</span> trains crossing entire oceans without major energy loss. At the coast, <span class="hlt">tsunamis</span> typically show <span class="hlt">wave</span> shoaling, funnelling and resonance effects as well as a significant run-up and backflow. <span class="hlt">Tsunami</span> <span class="hlt">waves</span> are caused by a sudden displacement of the water column due to a number of various trigger mechanisms. Such are earthquakes as the main trigger, submarine and subaerial mass wastings, volcanic activity, atmospheric disturbances (meteotsunamis) and cosmic impacts, as is demonstrated by giving corresponding examples from the past. <span class="hlt">Tsunamis</span> are known to have a significant sedimentary and geomorphological off- and onshore response. So-called tsunamites form allochthonous high-energy deposits that are left at the coast during <span class="hlt">tsunami</span> landfall. <span class="hlt">Tsunami</span> deposits show typical sedimentary features, as basal erosional unconformities, fining-upward and -landward, a high content of marine fossils, rip-up clasts from underlying units and mud caps, all reflecting the hydrodynamic processes during inundation. The on- and offshore behaviour of <span class="hlt">tsunamis</span> and related sedimentary processes can be simulated using hydro- and morphodynamic numerical models. The paper provides an overview of the basic <span class="hlt">tsunami</span> modelling techniques, including discretisation, guidelines for appropriate temporal and spatial resolution as well as the nesting method. Furthermore, the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH22A..03N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH22A..03N"><span>Should <span class="hlt">tsunami</span> models use a nonzero initial condition for horizontal velocity?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nava, G.; Lotto, G. C.; Dunham, E. M.</p> <p>2017-12-01</p> <p><span class="hlt">Tsunami</span> <span class="hlt">propagation</span> in the open ocean is most commonly modeled by solving the shallow water <span class="hlt">wave</span> equations. These equations require two initial conditions: one on sea surface height and another on depth-averaged horizontal particle velocity or, equivalently, horizontal momentum. While most modelers assume that initial velocity is zero, Y.T. Song and collaborators have argued for nonzero initial velocity, claiming that horizontal displacement of a sloping seafloor imparts significant horizontal momentum to the ocean. They show examples in which this effect increases the resulting <span class="hlt">tsunami</span> height by a factor of two or more relative to models in which initial velocity is zero. We test this claim with a "full-physics" integrated dynamic rupture and <span class="hlt">tsunami</span> model that couples the elastic response of the Earth to the linearized acoustic-gravitational response of a compressible ocean with gravity; the model self-consistently accounts for seismic <span class="hlt">waves</span> in the solid Earth, acoustic <span class="hlt">waves</span> in the ocean, and <span class="hlt">tsunamis</span> (with dispersion at short wavelengths). We run several full-physics simulations of subduction zone megathrust ruptures and <span class="hlt">tsunamis</span> in geometries with a sloping seafloor, using both idealized structures and a more realistic Tohoku structure. Substantial horizontal momentum is imparted to the ocean, but almost all momentum is carried away in the form of ocean acoustic <span class="hlt">waves</span>. We compare <span class="hlt">tsunami</span> <span class="hlt">propagation</span> in each full-physics simulation to that predicted by an equivalent shallow water <span class="hlt">wave</span> simulation with varying assumptions regarding initial conditions. We find that the initial horizontal velocity conditions proposed by Song and collaborators consistently overestimate the <span class="hlt">tsunami</span> amplitude and predict an inconsistent <span class="hlt">wave</span> profile. Finally, we determine <span class="hlt">tsunami</span> initial conditions that are rigorously consistent with our full-physics simulations by isolating the <span class="hlt">tsunami</span> <span class="hlt">waves</span> (from ocean acoustic and seismic <span class="hlt">waves</span>) at some final time, and backpropagating the <span class="hlt">tsunami</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFMNS21A..08D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFMNS21A..08D"><span>U.S. states and territories national <span class="hlt">tsunami</span> hazard assessment, historic record and sources for <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dunbar, P. K.; Weaver, C.</p> <p>2007-12-01</p> <p>In 2005, the U.S. National Science and Technology Council (NSTC) released a joint report by the sub-committee on Disaster Reduction and the U.S. Group on Earth Observations titled <span class="hlt">Tsunami</span> Risk Reduction for the United States: A Framework for Action (Framework). The Framework outlines the President's&pstrategy for reducing the United States <span class="hlt">tsunami</span> risk. The first specific action called for in the Framework is to "Develop standardized and coordinated <span class="hlt">tsunami</span> hazard and risk assessments for all coastal regions of the United States and its territories." Since NOAA is the lead agency for providing <span class="hlt">tsunami</span> forecasts and warnings and NOAA's National Geophysical Data Center (NGDC) catalogs information on global historic <span class="hlt">tsunamis</span>, NOAA/NGDC was asked to take the lead in conducting the first national <span class="hlt">tsunami</span> hazard assessment. Earthquakes or earthquake-generated landslides caused more than 85% of the <span class="hlt">tsunamis</span> in the NGDC <span class="hlt">tsunami</span> database. Since the United States Geological Survey (USGS) conducts research on earthquake hazards facing all of the United States and its territories, NGDC and USGS partnered together to conduct the first <span class="hlt">tsunami</span> hazard assessment for the United States and its territories. A complete <span class="hlt">tsunami</span> hazard and risk assessment consists of a hazard assessment, exposure and vulnerability assessment of buildings and people, and loss assessment. This report is an interim step towards a <span class="hlt">tsunami</span> risk assessment. The goal of this report is provide a qualitative assessment of the United States <span class="hlt">tsunami</span> hazard at the national level. Two different methods are used to assess the U.S. <span class="hlt">tsunami</span> hazard. The first method involves a careful examination of the NGDC historical <span class="hlt">tsunami</span> database. This resulted in a qualitative national <span class="hlt">tsunami</span> hazard assessment based on the distribution of runup heights and the frequency of runups. Although <span class="hlt">tsunami</span> deaths are a measure of risk rather than hazard, the known <span class="hlt">tsunami</span> deaths found in the NGDC database search were compared with the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19780038088&hterms=Transient+electromagnetic+pulse&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DTransient%2Belectromagnetic%2Bpulse','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19780038088&hterms=Transient+electromagnetic+pulse&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DTransient%2Belectromagnetic%2Bpulse"><span>On a method computing transient <span class="hlt">wave</span> <span class="hlt">propagation</span> in ionospheric regions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gray, K. G.; Bowhill, S. A.</p> <p>1978-01-01</p> <p>A consequence of an exoatmospheric nuclear burst is an electromagnetic pulse (EMP) radiated from it. In a region far enough away from the burst, where nonlinear effects can be ignored, the EMP can be represented by a large-amplitude narrow-time-width plane-<span class="hlt">wave</span> pulse. If the ionosphere intervenes the origin and destination of the EMP, frequency dispersion can cause significant changes in the original pulse upon reception. A method of computing these dispersive effects of transient <span class="hlt">wave</span> <span class="hlt">propagation</span> is summarized. The method described is different from the standard transform techniques and provides physical insight into the transient <span class="hlt">wave</span> process. The method, although exact, can be used in approximating the early-time transient response of an ionospheric region by a simple integration with only explicit knowledge of the electron density, electron collision frequency, and electron gyrofrequency required. As an illustration of the method, it is applied to a simple example and contrasted with the corresponding transform solution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040139876&hterms=Tidal+waves&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DTidal%2Bwaves','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040139876&hterms=Tidal+waves&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DTidal%2Bwaves"><span>Nonlinear <span class="hlt">Propagation</span> of Planet-Generated Tidal <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rafikov, R. R.</p> <p>2002-01-01</p> <p>The <span class="hlt">propagation</span> and evolution of planet-generated density <span class="hlt">waves</span> in protoplanetary disks is considered. The evolution of <span class="hlt">waves</span>, leading to shock formation and wake dissipation, is followed in the weakly nonlinear regime. The 2001 local approach of Goodman and Rafikov is extended to include the effects of surface density and temperature variations in the disk as well as the disk cylindrical geometry and nonuniform shear. <span class="hlt">Wave</span> damping due to shocks is demonstrated to be a nonlocal process spanning a significant fraction of the disk. Torques induced by the planet could be significant drivers of disk evolution on timescales of approx. 10(exp 6)-10(exp 7) yr, even in the absence of strong background viscosity. A global prescription for angular momentum deposition is developed that could be incorporated into the study of gap formation in a gaseous disk around the planet.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992PhFlA...4.2700F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992PhFlA...4.2700F"><span>Shock <span class="hlt">wave</span> <span class="hlt">propagation</span> in a magnetic flux tube</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ferriz-Mas, A.; Moreno-Insertis, F.</p> <p>1992-12-01</p> <p>The <span class="hlt">propagation</span> of a shock <span class="hlt">wave</span> in a magnetic flux tube is studied within the framework of the Brinkley-Kirkwood theory adapted to a radiating gas. Simplified thermodynamic paths along which the compressed plasma returns to its initial state are considered. It is assumed that the undisturbed medium is uniform and that the flux tube is optically thin. The shock <span class="hlt">waves</span> investigated, which are described with the aid of the thin flux-tube approximation, are essentially slow magnetohydrodynamic shocks modified by the constraint of lateral pressure balance between the flux tube and the surrounding field-free fluid; the confining external pressure must be balanced by the internal gas plus magnetic pressures. Exact analytical solutions giving the evolution of the shock <span class="hlt">wave</span> are obtained for the case of weak shocks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ShWav..28..683J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ShWav..28..683J"><span>Shock <span class="hlt">wave</span> <span class="hlt">propagation</span> within a confined multi-chamber system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Julien, B.; Sochet, I.; Tadini, P.; Vaillant, T.</p> <p>2018-07-01</p> <p>The influence of a variation of the opening ratios of rooms and side walls on the <span class="hlt">propagation</span> of a shock <span class="hlt">wave</span> within a confined multi-chamber system is analyzed through the evolution of some of the shock parameters (maximum overpressure and positive impulse). The shock <span class="hlt">wave</span> is generated by the detonation of a hemispherical gaseous charge in one of the rooms. Several small-scale experiments have been carried out using an adjustable model representative of a pyrotechnic workshop. Using the same approach as for a previous article dealing with the impact of the volume of the rooms, we were able to link the evolution of the arrival time of the shock <span class="hlt">wave</span> within the building with the reference obtained in the free field. Moreover, using a new parameter taking into account the opening ratios of the rooms and side walls, a predictive law was developed to model the maximal overpressure in the rooms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JAP...123f3902S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JAP...123f3902S"><span>Theory of electromagnetic <span class="hlt">wave</span> <span class="hlt">propagation</span> in ferromagnetic Rashba conductor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shibata, Junya; Takeuchi, Akihito; Kohno, Hiroshi; Tatara, Gen</p> <p>2018-02-01</p> <p>We present a comprehensive study of various electromagnetic <span class="hlt">wave</span> <span class="hlt">propagation</span> phenomena in a ferromagnetic bulk Rashba conductor from the perspective of quantum mechanical transport. In this system, both the space inversion and time reversal symmetries are broken, as characterized by the Rashba field α and magnetization M, respectively. First, we present a general phenomenological analysis of electromagnetic <span class="hlt">wave</span> <span class="hlt">propagation</span> in media with broken space inversion and time reversal symmetries based on the dielectric tensor. The dependence of the dielectric tensor on the <span class="hlt">wave</span> vector q and M is retained to first order. Then, we calculate the microscopic electromagnetic response of the current and spin of conduction electrons subjected to α and M, based on linear response theory and the Green's function method; the results are used to study the system optical properties. First, it is found that a large α enhances the anisotropic properties of the system and enlarges the frequency range in which the electromagnetic <span class="hlt">waves</span> have hyperbolic dispersion surfaces and exhibit unusual <span class="hlt">propagations</span> known as negative refraction and backward <span class="hlt">waves</span>. Second, we consider the electromagnetic cross-correlation effects (direct and inverse Edelstein effects) on the <span class="hlt">wave</span> <span class="hlt">propagation</span>. These effects stem from the lack of space inversion symmetry and yield q-linear off-diagonal components in the dielectric tensor. This induces a Rashba-induced birefringence, in which the polarization vector rotates around the vector (α ×q ) . In the presence of M, which breaks time reversal symmetry, there arises an anomalous Hall effect and the dielectric tensor acquires off-diagonal components linear in M. For α ∥M , these components yield the Faraday effect for the Faraday configuration q ∥M and the Cotton-Mouton effect for the Voigt configuration ( q ⊥M ). When α and M are noncollinear, M- and q-induced optical phenomena are possible, which include nonreciprocal directional dichroism in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.S53A1029L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.S53A1029L"><span><span class="hlt">Tsunami</span> Detection Systems for International Requirements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lawson, R. A.</p> <p>2007-12-01</p> <p>Results are presented regarding the first commercially available, fully operational, <span class="hlt">tsunami</span> detection system to have passed stringent U.S. government testing requirements and to have successfully demonstrated its ability to detect an actual <span class="hlt">tsunami</span> at sea. Spurred by the devastation of the December 26, 2004, Indian Ocean <span class="hlt">tsunami</span> that killed more than 230,000 people, the private sector actively supported the Intergovernmental Oceanographic Commission's (IOC"s) efforts to develop a <span class="hlt">tsunami</span> warning system and mitigation plan for the Indian Ocean region. As each country in the region developed its requirements, SAIC recognized that many of these underdeveloped countries would need significant technical assistance to fully execute their plans. With the original focus on data fusion, consequence assessment tools, and warning center architecture, it was quickly realized that the cornerstone of any <span class="hlt">tsunami</span> warning system would be reliable <span class="hlt">tsunami</span> detection buoys that could meet very stringent operational standards. Our goal was to leverage extensive experience in underwater surveillance and oceanographic sensing to produce an enhanced and reliable deep water sensor that could meet emerging international requirements. Like the NOAA Deep-ocean Assessment and Recording of <span class="hlt">Tsunamis</span> (DART TM ) buoy, the SAIC <span class="hlt">Tsunami</span> Buoy (STB) system consists of three subsystems: a surfaccommunications buoy subsystem, a bottom pressure recorder subsystem, and a buoy mooring subsystem. With the operational success that DART has demonstrated, SAIC decided to build and test to the same high standards. The <span class="hlt">tsunami</span> detection buoy system measures small changes in the depth of the deep ocean caused by <span class="hlt">tsunami</span> <span class="hlt">waves</span> as they <span class="hlt">propagate</span> past the sensor. This is accomplished by using an extremely sensitive bottom pressure sensor/recorder to measure very small changes in pressure as the <span class="hlt">waves</span> move past the buoy system. The bottom pressure recorder component includes a processor with algorithms that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRA..123..587L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRA..123..587L"><span>One-Dimensional Full <span class="hlt">Wave</span> Simulation of Equatorial Magnetosonic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in an Inhomogeneous Magnetosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Xu; Chen, Lunjin; Yang, Lixia; Xia, Zhiyang; Malaspina, David M.</p> <p>2018-01-01</p> <p>The effect of the plasmapause on equatorially radially <span class="hlt">propagating</span> fast magnetosonic (MS) <span class="hlt">waves</span> in the Earth's dipole magnetic field is studied by using finite difference time domain method. We run 1-D simulation for three different density profiles: (1) no plasmapause, (2) with a plasmapause, and (3) with a plasmapause accompanied with fine-scale density irregularity. We find that (1) without plasmapause the radially inward <span class="hlt">propagating</span> MS <span class="hlt">wave</span> can reach ionosphere and continuously <span class="hlt">propagate</span> to lower altitude if no damping mechanism is considered. The <span class="hlt">wave</span> properties follow the cold plasma dispersion relation locally along its trajectory. (2) For simulation with a plasmapause with a scale length of 0.006 RE compared to wavelength, only a small fraction of the MS <span class="hlt">wave</span> power is reflected by the plasmapause. WKB approximation is generally valid for such plasmapause. (3) The multiple fine-scale density irregularities near the outer edge of plasmapause can effectively block the MS <span class="hlt">wave</span> <span class="hlt">propagation</span>, resulting in a terminating boundary for MS <span class="hlt">waves</span> near the plasmapause.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004PhDT.......184P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004PhDT.......184P"><span>The interaction between a <span class="hlt">propagating</span> coastal vortex and topographic <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parry, Simon Wyn</p> <p></p> <p>This thesis investigates the motion of a point vortex near coastal topography in a rotating frame of reference at constant latitude (f-plane) in the linear and weakly nonlinear limits. Topography is considered in the form of an infinitely long escarpment running parallel to a wall. The vortex motion and topographic <span class="hlt">waves</span> are governed by the conservation of quasi-geostrophic potential vorticity in shallow water, from which a nonlinear system of equations is derived. First the linear limit is studied for three cases; a weak vortex on- and off-shelf and a weak vortex close to the wall. For the first two cases it is shown that to leading order the vortex motion is stationary and a solution for the topographic <span class="hlt">waves</span> at the escarpment can be found in terms of Fourier integrals. For a weak vortex close to a wall, the leading order solution is a steadily <span class="hlt">propagating</span> vortex with a topographic wavetrain at the step. Numerical results for the higher order interactions are also presented and explained in terms of conservation of momentum in the along-shore direction. For the second case a resonant interaction between the vortex and the <span class="hlt">waves</span> occurs when the vortex speed is equal to the maximum group velocity of the <span class="hlt">waves</span> and the linear response becomes unbounded at large times. Thus it becomes necessary to examine the weakly nonlinear near-resonant case. Using a long <span class="hlt">wave</span> approximation a nonlinear evolution equation for the interface separating the two regions of differing relative potential vorticity is derived and has similar form to the BDA (Benjamin, Davies, Acrivos 1967) equation. Results for the leading order steadily <span class="hlt">propagating</span> vortex and for the vortex-<span class="hlt">wave</span> feedback problem are calculated numerically using spectral multi-step Adams methods.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27908091','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27908091"><span>Higher order acoustoelastic Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> in stressed plates.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pei, Ning; Bond, Leonard J</p> <p>2016-11-01</p> <p>Modeling and experiments are used to investigate Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> in the direction perpendicular to an applied stress. Sensitivity, in terms of changes in velocity, for both symmetrical and anti-symmetrical modes was determined. Codes were developed based on analytical expressions for <span class="hlt">waves</span> in loaded plates and they were used to give <span class="hlt">wave</span> dispersion curves. The experimental system used a pair of compression <span class="hlt">wave</span> transducers on variable angle wedges, with set separation, and variable frequency tone burst excitation, on an aluminum plate 0.16 cm thick with uniaxial applied loads. The loads, which were up to 600 με, were measured using strain gages. Model results and experimental data are in good agreement. It was found that the change in Lamb <span class="hlt">wave</span> velocity, due to the acoustoelastic effect, for the S 1 mode exhibits about ten times more sensitive, in terms of velocity change, than the traditional bulk <span class="hlt">wave</span> measurements, and those performed using the fundamental Lamb modes. The data presented demonstrate the potential for the use of higher order Lamb modes for online industrial stress measurement in plate, and that the higher sensitivity seen offers potential for improved measurement systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26328726','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26328726"><span>A phase space approach to <span class="hlt">wave</span> <span class="hlt">propagation</span> with dispersion.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ben-Benjamin, Jonathan S; Cohen, Leon; Loughlin, Patrick J</p> <p>2015-08-01</p> <p>A phase space approximation method for linear dispersive <span class="hlt">wave</span> <span class="hlt">propagation</span> with arbitrary initial conditions is developed. The results expand on a previous approximation in terms of the Wigner distribution of a single mode. In contrast to this previously considered single-mode case, the approximation presented here is for the full <span class="hlt">wave</span> and is obtained by a different approach. This solution requires one to obtain (i) the initial modal functions from the given initial <span class="hlt">wave</span>, and (ii) the initial cross-Wigner distribution between different modal functions. The full <span class="hlt">wave</span> is the sum of modal functions. The approximation is obtained for general linear <span class="hlt">wave</span> equations by transforming the equations to phase space, and then solving in the new domain. It is shown that each modal function of the <span class="hlt">wave</span> satisfies a Schrödinger-type equation where the equivalent "Hamiltonian" operator is the dispersion relation corresponding to the mode and where the wavenumber is replaced by the wavenumber operator. Application to the beam equation is considered to illustrate the approach.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010PhDT.......113C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010PhDT.......113C"><span>Migrating diurnal tide variability induced by <span class="hlt">propagating</span> planetary <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chang, Loren C.</p> <p></p> <p>The migrating diurnal tide is one of the dominant dynamical features in the low latitudes of the Earth's Mesosphere and Lower Thermosphere (MLT) region, representing the atmospheric response to the largest component of solar forcing, <span class="hlt">propagating</span> upwards from excitation regions in the lower atmosphere. Ground-based observations of the tide have resolved short term variations attributed to nonlinear interactions between the tide and planetary <span class="hlt">waves</span> also in the region. However, the conditions, effects, and mechanisms of a planetary <span class="hlt">wave</span> - tidal interaction are still unclear. These questions are addressed using the NCAR Thermosphere Ionosphere Mesosphere Electrodynamics General Circulation Model (TIME-GCM) to examine two types of planetary <span class="hlt">waves</span>, known to attain significant amplitudes in the low latitude and equatorial region where the migrating diurnal tide is dominant. The quasi-two day <span class="hlt">wave</span> (QTDW) can rapidly amplify to large amplitudes from the summer hemisphere during post-solstice periods, while ultra fast Kelvin (UFK) <span class="hlt">waves</span> occur sporadically in the temperature and zonal wind fields of the equatorial lower thermosphere. While child <span class="hlt">waves</span> resulting from a nonlinear interaction are resolved in both cases, the response of the tidal structure and amplitudes to the two planetary <span class="hlt">waves</span> differs significantly. In the case of the QTDW, the migrating diurnal tide displays a general amplitude decrease of 20 - 40%, as well as a shortening of vertical wavelength by roughly 4 km. Nonlinear advection is found to result in energy transfer to and from the tide, resulting in latitudinal smoothing of the tidal structure. The QTDW also produces significant changes to the mean zonal winds in the equator and at summer mid to high latitudes that can also account for changes in tidal amplitude and vertical wavelength. Filtering of gravity <span class="hlt">waves</span> by the altered mean winds can also result in changes to the zonal mean zonal winds in the tropics. However, gravity <span class="hlt">wave</span> momentum forcing on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMOS21F..06C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMOS21F..06C"><span><span class="hlt">Wave</span> energy converter effects on <span class="hlt">wave</span> <span class="hlt">propagation</span>: A sensitivity study in Monterey Bay, CA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chang, G.; Jones, C. A.; Roberts, J.; Magalen, J.; Ruehl, K.; Chartrand, C.</p> <p>2014-12-01</p> <p>The development of renewable offshore energy in the United States is growing rapidly and <span class="hlt">wave</span> energy is one of the largest resources currently being evaluated. The deployment of <span class="hlt">wave</span> energy converter (WEC) arrays required to harness this resource could feasibly number in the hundreds of individual devices. The WEC arrays have the potential to alter nearshore <span class="hlt">wave</span> <span class="hlt">propagation</span> and circulation patterns and ecosystem processes. As the industry progresses from pilot- to commercial-scale it is important to understand and quantify the effects of WECs on the natural nearshore processes that support a local, healthy ecosystem. To help accelerate the realization of commercial-scale <span class="hlt">wave</span> power, predictive modeling tools have been developed and utilized to evaluate the likelihood of environmental impact. At present, direct measurements of the effects of different types of WEC arrays on nearshore <span class="hlt">wave</span> <span class="hlt">propagation</span> are not available; therefore <span class="hlt">wave</span> model simulations provide the groundwork for investigations of the sensitivity of model results to prescribed WEC characteristics over a range of anticipated <span class="hlt">wave</span> conditions. The present study incorporates a modified version of an industry standard <span class="hlt">wave</span> modeling tool, SWAN (Simulating <span class="hlt">WAves</span> Nearshore), to simulate <span class="hlt">wave</span> <span class="hlt">propagation</span> through a hypothetical WEC array deployment site on the California coast. The modified SWAN, referred to as SNL-SWAN, incorporates device-specific WEC power take-off characteristics to more accurately evaluate a WEC device's effects on <span class="hlt">wave</span> <span class="hlt">propagation</span>. The primary objectives were to investigate the effects of a range of WEC devices and device and array characteristics (e.g., device spacing, number of WECs in an array) on nearshore <span class="hlt">wave</span> <span class="hlt">propagation</span> using SNL-SWAN model simulations. Results showed that significant <span class="hlt">wave</span> height was most sensitive to variations in WEC device type and size and the number of WEC devices in an array. Locations in the lee centerline of the arrays in each modeled scenario showed the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16..752K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16..752K"><span>Display of historical and hypothetical <span class="hlt">tsunami</span> on the coast of Sakhalin Island</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kostenko, Irina; Zaytsev, Andrey; Kurkin, Andrey; Yalciner, Ahmet</p> <p>2014-05-01</p> <p><span class="hlt">Tsunami</span> <span class="hlt">waves</span> achieve the coast of the Sakhalin Island and their sources are located in the Japan Sea, in the Okhotsk Sea, in Kuril Islands region and in the Pacific Ocean. Study of <span class="hlt">tsunami</span> generation characteristics and its <span class="hlt">propagation</span> allows studying display of the <span class="hlt">tsunami</span> on the various parts of the island coast. For this purpose the series of computational experiments of some historical <span class="hlt">tsunamis</span> was carried out. Their sources located in Japan Sea and Kuril Islands region. The simulation results are compared with the observations. Analysis of all recorded historical <span class="hlt">tsunami</span> on coast of Sakhalin Island was done. To identify the possible display of the <span class="hlt">tsunami</span> on the coast of Sakhalin Island the series of computational experiments of hypothetical <span class="hlt">tsunamis</span> was carried out. Their sources located in the Japan Sea and in the Okhotsk Sea. There were used hydrodynamic sources. There were used different parameters of sources (length, width, height, raising and lowering of sea level), which correspond to earthquakes of various magnitudes. The analysis of the results was carried out. Pictures of the distribution of maximum amplitudes from each <span class="hlt">tsunami</span> were done. Areas of Okhotsk Sea, Japan Sea and offshore strip of Sakhalin Island with maximum <span class="hlt">tsunami</span> amplitudes were defined. Graphs of the distribution of maximum <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights along the coast of the Sakhalin Island were plotted. Based on shallow-water equation <span class="hlt">tsunami</span> numerical code NAMI DANCE was used for numerical simulations. This work was supported by ASTARTE project.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005APS..SHK.Z2004H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005APS..SHK.Z2004H"><span>Modeling the <span class="hlt">Propagation</span> of Shock <span class="hlt">Waves</span> in Metals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Howard, W. Michael</p> <p>2005-07-01</p> <p>We present modeling results for the <span class="hlt">propagation</span> of strong shock <span class="hlt">waves</span> in metals. In particular, we use an arbitrary Lagrange Eulerian (ALE3D) code to model the <span class="hlt">propagation</span> of strong pressure <span class="hlt">waves</span> (P ˜300 to 400 kbars) generated with high explosives in contact with aluminum cylinders. The aluminum cylinders are assumed to be both flat-topped and have large-amplitude curved surfaces. We use 3D Lagrange mechanics. For the aluminum we use a rate-independent Steinberg-Guinan model, where the yield strength and bulk modulus depends on pressure, density and temperature. The calculation of the melt temperature is based on the Lindermann law. At melt the yield strength and bulk modulus is set to zero. The pressure is represented as a seven-term polynomial as a function of density. For the HMX-based high explosive, we use a JWL, with a program burn model that gives the correct detonation velocity and C-J pressure (P ˜ 390 kbars). For the case of the large-amplitude curved surface, we discuss the evolving shock structure in terms of the early shock <span class="hlt">propagation</span> experiments by Sakharov. We also discuss the dependence of our results upon our material model for aluminum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11736134','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11736134"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in media having negative permittivity and permeability.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ziolkowski, R W; Heyman, E</p> <p>2001-11-01</p> <p><span class="hlt">Wave</span> <span class="hlt">propagation</span> in a double negative (DNG) medium, i.e., a medium having negative permittivity and negative permeability, is studied both analytically and numerically. The choices of the square root that leads to the index of refraction and the <span class="hlt">wave</span> impedance in a DNG medium are determined by imposing analyticity in the complex frequency domain, and the corresponding <span class="hlt">wave</span> properties associated with each choice are presented. These monochromatic concepts are then tested critically via a one-dimensional finite difference time domain (FDTD) simulation of the <span class="hlt">propagation</span> of a causal, pulsed plane <span class="hlt">wave</span> in a matched, lossy Drude model DNG medium. The causal responses of different spectral regimes of the medium with positive or negative refractive indices are studied by varying the carrier frequency of narrowband pulse excitations. The smooth transition of the phenomena associated with a DNG medium from its early-time nondispersive behavior to its late-time monochromatic response is explored with wideband pulse excitations. These FDTD results show conclusively that the square root choice leading to a negative index of refraction and positive <span class="hlt">wave</span> impedance is the correct one, and that this choice is consistent with the overall causality of the response. An analytical, exact frequency domain solution to the scattering of a <span class="hlt">wave</span> from a DNG slab is also given and is used to characterize several physical effects. This solution is independent of the choice of the square roots for the index of refraction and the <span class="hlt">wave</span> impedance, and thus avoids any controversy that may arise in connection with the signs of these constituents. The DNG slab solution is used to critically examine the perfect lens concept suggested recently by Pendry. It is shown that the perfect lens effect exists only under the special case of a DNG medium with epsilon(omega)=mu(omega)=-1 that is both lossless and nondispersive. Otherwise, the closed form solutions for the field structure reveal that the DNG slab</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992PhDT........51T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992PhDT........51T"><span>Surface <span class="hlt">Wave</span> <span class="hlt">Propagation</span> on a Laterally Heterogeneous Earth</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tromp, Jeroen</p> <p>1992-01-01</p> <p>Love and Rayleigh <span class="hlt">waves</span> <span class="hlt">propagating</span> on the surface of the Earth exhibit path, phase and amplitude anomalies as a result of the lateral heterogeneity of the mantle. In the JWKB approximation, these anomalies can be determined by tracing surface <span class="hlt">wave</span> trajectories, and calculating phase and amplitude anomalies along them. A time- or frequency -domain JWKB analysis yields local eigenfunctions, local dispersion relations, and conservation laws for the surface <span class="hlt">wave</span> energy. The local dispersion relations determine the surface <span class="hlt">wave</span> trajectories, and the energy equations determine the surface <span class="hlt">wave</span> amplitudes. On an anisotrophic Earth model the local dispersion relation and the local vertical eigenfunctions depend explicitly on the direction of the local wavevector. Apart from the usual dynamical phase, which is the integral of the local wavevector along a raypath, there is an additional variation is phase. This additional phase, which is an analogue of the Berry phase in adiabatic quantum mechanics, vanishes in a waveguide with a local vertical two-fold symmetry axis or a local horizontal mirror plane. JWKB theory breaks down in the vicinity of caustics, where neighboring rays merge and the surface <span class="hlt">wave</span> amplitude diverges. Based upon a potential representation of the surface <span class="hlt">wave</span> field, a uniformly valid Maslov theory can be obtained. Surface <span class="hlt">wave</span> trajectories are determined by a system of four ordinary differential equations which define a three-dimensional manifold in four-dimensional phase space (theta,phi,k_theta,k _phi), where theta is colatitude, phi is longitude, and k_theta and k _phi are the covariant components of the wavevector. There are no caustics in phase space; it is only when the rays in phase space are projected onto configuration space (theta,phi), the mixed spaces (k_theta,phi ) and (theta,k_phi), or onto momentum space (k_theta,k _phi), that caustics occur. The essential strategy is to employ a mixed or momentum space representation of the wavefield in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH23A1852S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH23A1852S"><span>Benchmarking on <span class="hlt">Tsunami</span> Currents with ComMIT</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sharghi vand, N.; Kanoglu, U.</p> <p>2015-12-01</p> <p>There were no standards for the validation and verification of <span class="hlt">tsunami</span> numerical models before 2004 Indian Ocean <span class="hlt">tsunami</span>. Even, number of numerical models has been used for inundation mapping effort, evaluation of critical structures, etc. without validation and verification. After 2004, NOAA Center for <span class="hlt">Tsunami</span> Research (NCTR) established standards for the validation and verification of <span class="hlt">tsunami</span> numerical models (Synolakis et al. 2008 Pure Appl. Geophys. 165, 2197-2228), which will be used evaluation of critical structures such as nuclear power plants against <span class="hlt">tsunami</span> attack. NCTR presented analytical, experimental and field benchmark problems aimed to estimate maximum runup and accepted widely by the community. Recently, benchmark problems were suggested by the US National <span class="hlt">Tsunami</span> Hazard Mitigation Program Mapping & Modeling Benchmarking Workshop: <span class="hlt">Tsunami</span> Currents on February 9-10, 2015 at Portland, Oregon, USA (http://nws.weather.gov/nthmp/index.html). These benchmark problems concentrated toward validation and verification of <span class="hlt">tsunami</span> numerical models on <span class="hlt">tsunami</span> currents. Three of the benchmark problems were: current measurement of the Japan 2011 <span class="hlt">tsunami</span> in Hilo Harbor, Hawaii, USA and in Tauranga Harbor, New Zealand, and single long-period <span class="hlt">wave</span> <span class="hlt">propagating</span> onto a small-scale experimental model of the town of Seaside, Oregon, USA. These benchmark problems were implemented in the Community Modeling Interface for <span class="hlt">Tsunamis</span> (ComMIT) (Titov et al. 2011 Pure Appl. Geophys. 168, 2121-2131), which is a user-friendly interface to the validated and verified Method of Splitting <span class="hlt">Tsunami</span> (MOST) (Titov and Synolakis 1995 J. Waterw. Port Coastal Ocean Eng. 121, 308-316) model and is developed by NCTR. The modeling results are compared with the required benchmark data, providing good agreements and results are discussed. Acknowledgment: The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22489590-electronically-nonadiabatic-wave-packet-propagation-using-frozen-gaussian-scattering','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22489590-electronically-nonadiabatic-wave-packet-propagation-using-frozen-gaussian-scattering"><span>Electronically nonadiabatic <span class="hlt">wave</span> packet <span class="hlt">propagation</span> using frozen Gaussian scattering</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kondorskiy, Alexey D., E-mail: kondor@sci.lebedev.ru; Nanbu, Shinkoh, E-mail: shinkoh.nanbu@sophia.ac.jp</p> <p>2015-09-21</p> <p>We present an approach, which allows to employ the adiabatic <span class="hlt">wave</span> packet <span class="hlt">propagation</span> technique and semiclassical theory to treat the nonadiabatic processes by using trajectory hopping. The approach developed generates a bunch of hopping trajectories and gives all additional information to incorporate the effect of nonadiabatic coupling into the <span class="hlt">wave</span> packet dynamics. This provides an interface between a general adiabatic frozen Gaussian <span class="hlt">wave</span> packet <span class="hlt">propagation</span> method and the trajectory surface hopping technique. The basic idea suggested in [A. D. Kondorskiy and H. Nakamura, J. Chem. Phys. 120, 8937 (2004)] is revisited and complemented in the present work by the elaborationmore » of efficient numerical algorithms. We combine our approach with the adiabatic Herman-Kluk frozen Gaussian approximation. The efficiency and accuracy of the resulting method is demonstrated by applying it to popular benchmark model systems including three Tully’s models and 24D model of pyrazine. It is shown that photoabsorption spectrum is successfully reproduced by using a few hundreds of trajectories. We employ the compact finite difference Hessian update scheme to consider feasibility of the ab initio “on-the-fly” simulations. It is found that this technique allows us to obtain the reliable final results using several Hessian matrix calculations per trajectory.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18564596','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18564596"><span>Modeling of shock <span class="hlt">wave</span> <span class="hlt">propagation</span> in large amplitude ultrasound.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pinton, Gianmarco F; Trahey, Gregg E</p> <p>2008-01-01</p> <p>The Rankine-Hugoniot relation for shock <span class="hlt">wave</span> <span class="hlt">propagation</span> describes the shock speed of a nonlinear <span class="hlt">wave</span>. This paper investigates time-domain numerical methods that solve the nonlinear parabolic <span class="hlt">wave</span> equation, or the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation, and the conditions they require to satisfy the Rankine-Hugoniot relation. Two numerical methods commonly used in hyperbolic conservation laws are adapted to solve the KZK equation: Godunov's method and the monotonic upwind scheme for conservation laws (MUSCL). It is shown that they satisfy the Rankine-Hugoniot relation regardless of attenuation. These two methods are compared with the current implicit solution based method. When the attenuation is small, such as in water, the current method requires a degree of grid refinement that is computationally impractical. All three numerical methods are compared in simulations for lithotripters and high intensity focused ultrasound (HIFU) where the attenuation is small compared to the nonlinearity because much of the <span class="hlt">propagation</span> occurs in water. The simulations are performed on grid sizes that are consistent with present-day computational resources but are not sufficiently refined for the current method to satisfy the Rankine-Hugoniot condition. It is shown that satisfying the Rankine-Hugoniot conditions has a significant impact on metrics relevant to lithotripsy (such as peak pressures) and HIFU (intensity). Because the Godunov and MUSCL schemes satisfy the Rankine-Hugoniot conditions on coarse grids, they are particularly advantageous for three-dimensional simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22370359-synthetic-observations-wave-propagation-sunspot-umbra','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22370359-synthetic-observations-wave-propagation-sunspot-umbra"><span>Synthetic observations of <span class="hlt">wave</span> <span class="hlt">propagation</span> in a sunspot umbra</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Felipe, T.; Socas-Navarro, H.; Khomenko, E.</p> <p>2014-11-01</p> <p>Spectropolarimetric temporal series from Fe I λ6301.5 Å and Ca II infrared triplet lines are obtained by applying the Stokes synthesis code NICOLE to a numerical simulation of <span class="hlt">wave</span> <span class="hlt">propagation</span> in a sunspot umbra from MANCHA code. The analysis of the phase difference between Doppler velocity and intensity core oscillations of the Fe I λ6301.5 Å line reveals that variations in the intensity are produced by opacity fluctuations rather than intrinsic temperature oscillations, except for frequencies between 5 and 6.5 mHz. On the other hand, the photospheric magnetic field retrieved from the weak field approximation provides the intrinsic magnetic fieldmore » oscillations associated to <span class="hlt">wave</span> <span class="hlt">propagation</span>. Our results suggest that this is due to the low magnetic field gradient of our sunspot model. The Stokes parameters of the chromospheric Ca II infrared triplet lines show striking variations as shock <span class="hlt">waves</span> travel through the formation height of the lines, including emission self-reversals in the line core and highly abnormal Stokes V profiles. Magnetic field oscillations inferred from the Ca II infrared lines using the weak field approximation appear to be related with the magnetic field strength variation between the photosphere and the chromosphere.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3055284','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3055284"><span>Evaluation of a <span class="hlt">wave</span>-vector-frequency-domain method for nonlinear <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Jing, Yun; Tao, Molei; Clement, Greg T.</p> <p>2011-01-01</p> <p>A <span class="hlt">wave</span>-vector-frequency-domain method is presented to describe one-directional forward or backward acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span> in a nonlinear homogeneous medium. Starting from a frequency-domain representation of the second-order nonlinear acoustic <span class="hlt">wave</span> equation, an implicit solution for the nonlinear term is proposed by employing the Green’s function. Its approximation, which is more suitable for numerical implementation, is used. An error study is carried out to test the efficiency of the model by comparing the results with the Fubini solution. It is shown that the error grows as the <span class="hlt">propagation</span> distance and step-size increase. However, for the specific case tested, even at a step size as large as one wavelength, sufficient accuracy for plane-<span class="hlt">wave</span> <span class="hlt">propagation</span> is observed. A two-dimensional steered transducer problem is explored to verify the nonlinear acoustic field directional independence of the model. A three-dimensional single-element transducer problem is solved to verify the forward model by comparing it with an existing nonlinear <span class="hlt">wave</span> <span class="hlt">propagation</span> code. Finally, backward-projection behavior is examined. The sound field over a plane in an absorptive medium is backward projected to the source and compared with the initial field, where good agreement is observed. PMID:21302985</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NHESS..17..641Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NHESS..17..641Z"><span>A numerical study of <span class="hlt">tsunami</span> <span class="hlt">wave</span> impact and run-up on coastal cliffs using a CIP-based model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Xizeng; Chen, Yong; Huang, Zhenhua; Hu, Zijun; Gao, Yangyang</p> <p>2017-05-01</p> <p>There is a general lack of understanding of <span class="hlt">tsunami</span> <span class="hlt">wave</span> interaction with complex geographies, especially the process of inundation. Numerical simulations are performed to understand the effects of several factors on <span class="hlt">tsunami</span> <span class="hlt">wave</span> impact and run-up in the presence of gentle submarine slopes and coastal cliffs, using an in-house code, a constrained interpolation profile (CIP)-based model. The model employs a high-order finite difference method, the CIP method, as the flow solver; utilizes a VOF-type method, the tangent of hyperbola for interface capturing/slope weighting (THINC/SW) scheme, to capture the free surface; and treats the solid boundary by an immersed boundary method. A series of incident <span class="hlt">waves</span> are arranged to interact with varying coastal geographies. Numerical results are compared with experimental data and good agreement is obtained. The influences of gentle submarine slope, coastal cliff and incident <span class="hlt">wave</span> height are discussed. It is found that the <span class="hlt">tsunami</span> amplification factor varying with incident <span class="hlt">wave</span> is affected by gradient of cliff slope, and the critical value is about 45°. The run-up on a toe-erosion cliff is smaller than that on a normal cliff. The run-up is also related to the length of a gentle submarine slope with a critical value of about 2.292 m in the present model for most cases. The impact pressure on the cliff is extremely large and concentrated, and the backflow effect is non-negligible. Results of our work are highly precise and helpful in inverting <span class="hlt">tsunami</span> source and forecasting disaster.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3393603','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3393603"><span>Fabric dependence of <span class="hlt">wave</span> <span class="hlt">propagation</span> in anisotropic porous media</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cowin, Stephen C.; Cardoso, Luis</p> <p>2012-01-01</p> <p>Current diagnosis of bone loss and osteoporosis is based on the measurement of the Bone Mineral Density (BMD) or the apparent mass density. Unfortunately, in most clinical ultrasound densitometers: 1) measurements are often performed in a single anatomical direction, 2) only the first <span class="hlt">wave</span> arriving to the ultrasound probe is characterized, and 3) the analysis of bone status is based on empirical relationships between measurable quantities such as Speed of Sound (SOS) and Broadband Ultrasound Attenuation (BUA) and the density of the porous medium. However, the existence of a second <span class="hlt">wave</span> in cancellous bone has been reported, which is an unequivocal signature of poroelastic media, as predicted by Biot’s poroelastic <span class="hlt">wave</span> <span class="hlt">propagation</span> theory. In this paper the governing equations for <span class="hlt">wave</span> motion in the linear theory of anisotropic poroelastic materials are developed and extended to include the dependence of the constitutive relations upon fabric - a quantitative stereological measure of the degree of structural anisotropy in the pore architecture of a porous medium. This fabric-dependent anisotropic poroelastic approach is a theoretical framework to describe the microarchitectural-dependent relationship between measurable <span class="hlt">wave</span> properties and the elastic constants of trabecular bone, and thus represents an alternative for bone quality assessment beyond BMD alone. PMID:20461539</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26066234','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26066234"><span><span class="hlt">Propagation</span> of spiral <span class="hlt">waves</span> pinned to circular and rectangular obstacles.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sutthiopad, Malee; Luengviriya, Jiraporn; Porjai, Porramain; Phantu, Metinee; Kanchanawarin, Jarin; Müller, Stefan C; Luengviriya, Chaiya</p> <p>2015-05-01</p> <p>We present an investigation of spiral <span class="hlt">waves</span> pinned to circular and rectangular obstacles with different circumferences in both thin layers of the Belousov-Zhabotinsky reaction and numerical simulations with the Oregonator model. For circular objects, the area always increases with the circumference. In contrast, we varied the circumference of rectangles with equal areas by adjusting their width w and height h. For both obstacle forms, the <span class="hlt">propagating</span> parameters (i.e., wavelength, <span class="hlt">wave</span> period, and velocity of pinned spiral <span class="hlt">waves</span>) increase with the circumference, regardless of the obstacle area. Despite these common features of the parameters, the forms of pinned spiral <span class="hlt">waves</span> depend on the obstacle shapes. The structures of spiral <span class="hlt">waves</span> pinned to circles as well as rectangles with the ratio w/h∼1 are similar to Archimedean spirals. When w/h increases, deformations of the spiral shapes are observed. For extremely thin rectangles with w/h≫1, these shapes can be constructed by employing semicircles with different radii which relate to the obstacle width and the core diameter of free spirals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004wpse.book.....J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004wpse.book.....J"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span>, scattering and emission in complex media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jin, Ya-Qiu</p> <p></p> <p>I. Polarimetric scattering and SAR imagery. EM <span class="hlt">wave</span> <span class="hlt">propagation</span> and scattering in polarimetric SAR interferometry / S. R. Cloude. Terrain topographic inversion from single-pass polarimetric SAR image data by using polarimetric stokes parameters and morphological algorithm / Y. Q. Jin, L. Luo. Road detection in forested area using polarimetric SAR / G. W. Dong ... [et al.]. Research on some problems about SAR radiometric resolution / G. Dong ... [et al.]. A fast image matching algorithm for remote sensing applications / Z. Q. Hou ... [et al.]. A new algorithm of noised remote sensing image fusion based on steerable filters / X. Kang ... [et al.]. Adaptive noise reduction of InSAR data based on anisotropic diffusion models and their applications to phase unwrapping / C. Wang, X. Gao, H. Zhang -- II. Scattering from randomly rough surfaces. Modeling tools for backscattering from rough surfaces / A. K. Fung, K. S. Chen. Pseudo-nondiffracting beams from rough surface scattering / E. R. Méndez, T. A. Leskova, A. A. Maradudin. Surface roughness clutter effects in GPR modeling and detection / C. Rappaport. Scattering from rough surfaces with small slopes / M. Saillard, G. Soriano. Polarization and spectral characteristics of radar signals reflected by sea-surface / V. A. Butko, V. A. Khlusov, L. I. Sharygina. Simulation of microwave scattering from wind-driven ocean surfaces / M. Y. Xia ... [et al.]. HF surface <span class="hlt">wave</span> radar tests at the Eastern China Sea / X. B. Wu ... [et al.] -- III. Electromagnetics of complex materials. <span class="hlt">Wave</span> <span class="hlt">propagation</span> in plane-parallel metamaterial and constitutive relations / A. Ishimaru ... [et al.]. Two dimensional periodic approach for the study of left-handed metamaterials / T. M. Grzegorczyk ... [et al.]. Numerical analysis of the effective constitutive parameters of a random medium containing small chiral spheres / Y. Nanbu, T. Matsuoka, M. Tateiba. <span class="hlt">Wave</span> <span class="hlt">propagation</span> in inhomogeneous media: from the Helmholtz to the Ginzburg -Landau equation / M</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH53D..04R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH53D..04R"><span><span class="hlt">Tsunami</span> normal modes with solid earth and atmospheric coupling and inversion of the TEC data to estimate <span class="hlt">tsunami</span> water height in the case of the Queen Charlotte <span class="hlt">tsunami</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rakoto, V.; Lognonne, P. H.; Rolland, L.</p> <p>2016-12-01</p> <p>Large underwater earthquakes (Mw > 7) can transmit part of their energy to the surrounding ocean through large sea-floor motions, generating <span class="hlt">tsunamis</span> that <span class="hlt">propagate</span> over long distances. The forcing effect of long period ocean surface vibrations due to <span class="hlt">tsunami</span> <span class="hlt">waves</span> on the atmosphere trigger atmospheric internal gravity <span class="hlt">waves</span> (IGWs) that induce ionospheric disturbances when they reach the upper atmosphere. In this poster, we study the IGWs associated to <span class="hlt">tsunamis</span> using a normal modes 1D modeling approach. Our model is first applied to the case of the October 2012 Haida Gwaii <span class="hlt">tsunami</span> observed offshore Hawaii. We found three resonances between <span class="hlt">tsunami</span> modes and the atmospheric gravity modes occurring around 1.5 mHz, 2 mHz and 2.5 mHz, with a large fraction of the energy of the <span class="hlt">tsunami</span> modes transferred from the ocean to the atmosphere. At theses frequencies, the gravity branches are interacting with the <span class="hlt">tsunami</span> one and have large amplitude in the ocean. As opposed to the <span class="hlt">tsunami</span>, a fraction of their energy is therefore transferred from the atmosphere to the ocean. We also show that the fundamental of the gravity <span class="hlt">waves</span> should arrive before the <span class="hlt">tsunami</span> due to higher group velocity below 1.6 mHz. We demonstrate that only the 1.5 mHz resonance of the <span class="hlt">tsunami</span> mode can trigger observable ionospheric perturbations, most often monitored using GPS dual-frequency measurements. Indeed, we show that the modes at 2 mHz and 2.5 mHz are already evanescent at the height of the F2 peak and have little energy in the ionosphere. This normal modes modeling offers a novel and comprehensive study of the transfer function from a <span class="hlt">propagating</span> <span class="hlt">tsunami</span> to the upper atmosphere. In particular, we can invert the perturbed TEC data induced by a <span class="hlt">tsunami</span> in order to estimate the amplitude of the <span class="hlt">tsunami</span> waveform using a least square method. This method has been performed in the case of the Haida Gwaii <span class="hlt">tsunami</span>. The results showed a good agreement with the measurement of the dart buoy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140010556','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140010556"><span>Gravity <span class="hlt">Wave</span> Variances and <span class="hlt">Propagation</span> Derived from AIRS Radiances</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gong, Jie; Wu, Dong L.; Eckermann, S. D.</p> <p>2012-01-01</p> <p>As the first gravity <span class="hlt">wave</span> (GW) climatology study using nadir-viewing infrared sounders, 50 Atmospheric Infrared Sounder (AIRS) radiance channels are selected to estimate GW variances at pressure levels between 2-100 hPa. The GW variance for each scan in the cross-track direction is derived from radiance perturbations in the scan, independently of adjacent scans along the orbit. Since the scanning swaths are perpendicular to the satellite orbits, which are inclined meridionally at most latitudes, the zonal component of GW <span class="hlt">propagation</span> can be inferred by differencing the variances derived between the westmost and the eastmost viewing angles. Consistent with previous GW studies using various satellite instruments, monthly mean AIRS variance shows large enhancements over meridionally oriented mountain ranges as well as some islands at winter hemisphere high latitudes. Enhanced <span class="hlt">wave</span> activities are also found above tropical deep convective regions. GWs prefer to <span class="hlt">propagate</span> westward above mountain ranges, and eastward above deep convection. AIRS 90 field-of-views (FOVs), ranging from +48 deg. to -48 deg. off nadir, can detect large-amplitude GWs with a phase velocity <span class="hlt">propagating</span> preferentially at steep angles (e.g., those from orographic and convective sources). The annual cycle dominates the GW variances and the preferred <span class="hlt">propagation</span> directions for all latitudes. Indication of a weak two-year variation in the tropics is found, which is presumably related to the Quasi-biennial oscillation (QBO). AIRS geometry makes its out-tracks capable of detecting GWs with vertical wavelengths substantially shorter than the thickness of instrument weighting functions. The novel discovery of AIRS capability of observing shallow inertia GWs will expand the potential of satellite GW remote sensing and provide further constraints on the GW drag parameterization schemes in the general circulation models (GCMs).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21344675-wave-propagation-downstream-high-power-helicon-dipolelike-magnetic-field','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21344675-wave-propagation-downstream-high-power-helicon-dipolelike-magnetic-field"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> downstream of a high power helicon in a dipolelike magnetic field</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Prager, James; Winglee, Robert; Roberson, B. Race</p> <p>2010-01-15</p> <p>The <span class="hlt">wave</span> <span class="hlt">propagating</span> downstream of a high power helicon source in a diverging magnetic field was investigated experimentally. The magnetic field of the <span class="hlt">wave</span> has been measured both axially and radially. The three-dimensional structure of the <span class="hlt">propagating</span> <span class="hlt">wave</span> is observed and its wavelength and phase velocity are determined. The measurements are compared to predictions from helicon theory and that of a freely <span class="hlt">propagating</span> whistler <span class="hlt">wave</span>. The implications of this work on the helicon as a thruster are also discussed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S32A..03F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S32A..03F"><span>Duration of <span class="hlt">Tsunami</span> Generation Longer than Duration of Seismic <span class="hlt">Wave</span> Generation in the 2011 Mw 9.0 Tohoku-Oki Earthquake</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fujihara, S.; Korenaga, M.; Kawaji, K.; Akiyama, S.</p> <p>2013-12-01</p> <p>We try to compare and evaluate the nature of <span class="hlt">tsunami</span> generation and seismic <span class="hlt">wave</span> generation in occurrence of the 2011 Tohoku-Oki earthquake (hereafter, called as TOH11), in terms of two type of moment rate functions, inferred from finite source imaging of <span class="hlt">tsunami</span> waveforms and seismic waveforms. Since 1970's, the nature of "<span class="hlt">tsunami</span> earthquakes" has been discussed in many researches (e.g. Kanamori, 1972; Kanamori and Kikuchi, 1993; Kikuchi and Kanamori, 1995; Ide et al., 1993; Satake, 1994) mostly based on analysis of seismic waveform data , in terms of the "slow" nature of <span class="hlt">tsunami</span> earthquakes (e.g., the 1992 Nicaragura earthquake). Although TOH11 is not necessarily understood as a <span class="hlt">tsunami</span> earthquake, TOH11 is one of historical earthquakes that simultaneously generated large seismic <span class="hlt">waves</span> and <span class="hlt">tsunami</span>. Also, TOH11 is one of earthquakes which was observed both by seismic observation network and <span class="hlt">tsunami</span> observation network around the Japanese islands. Therefore, for the purpose of analyzing the nature of <span class="hlt">tsunami</span> generation, we try to utilize <span class="hlt">tsunami</span> waveform data as much as possible. In our previous studies of TOH11 (Fujihara et al., 2012a; Fujihara et al., 2012b), we inverted <span class="hlt">tsunami</span> waveforms at GPS <span class="hlt">wave</span> gauges of NOWPHAS to image the spatio-temporal slip distribution. The "temporal" nature of our <span class="hlt">tsunami</span> source model is generally consistent with the other <span class="hlt">tsunami</span> source models (e.g., Satake et al, 2013). For seismic waveform inversion based on 1-D structure, here we inverted broadband seismograms at GSN stations based on the teleseismic body-<span class="hlt">wave</span> inversion scheme (Kikuchi and Kanamori, 2003). Also, for seismic waveform inversion considering the inhomogeneous internal structure, we inverted strong motion seismograms at K-NET and KiK-net stations, based on 3-D Green's functions (Fujihara et al., 2013a; Fujihara et al., 2013b). The gross "temporal" nature of our seismic source models are generally consistent with the other seismic source models (e.g., Yoshida et al</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22403308-dispersion-relations-electromagnetic-wave-propagation-chiral-plasmas','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22403308-dispersion-relations-electromagnetic-wave-propagation-chiral-plasmas"><span>Dispersion relations for electromagnetic <span class="hlt">wave</span> <span class="hlt">propagation</span> in chiral plasmas</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gao, M. X.; Guo, B., E-mail: binguo@whut.edu.cn; Peng, L.</p> <p>2014-11-15</p> <p>The dispersion relations for electromagnetic <span class="hlt">wave</span> <span class="hlt">propagation</span> in chiral plasmas are derived using a simplified method and investigated in detail. With the help of the dispersion relations for each eignwave, we explore how the chiral plasmas exhibit negative refraction and investigate the frequency region for negative refraction. The results show that chirality can induce negative refraction in plasmas. Moreover, both the degree of chirality and the external magnetic field have a significant effect on the critical frequency and the bandwidth of the frequency for negative refraction in chiral plasmas. The parameter dependence of the effects is calculated and discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/40230962-regular-wave-propagation-out-noise-chemical-active-media','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/40230962-regular-wave-propagation-out-noise-chemical-active-media"><span>Regular <span class="hlt">Wave</span> <span class="hlt">Propagation</span> Out of Noise in Chemical Active Media</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Alonso, S.; Sendina-Nadal, I.; Perez-Munuzuri, V.</p> <p>2001-08-13</p> <p>A pacemaker, regularly emitting chemical <span class="hlt">waves</span>, is created out of noise when an excitable photosensitive Belousov-Zhabotinsky medium, strictly unable to autonomously initiate autowaves, is forced with a spatiotemporal patterned random illumination. These experimental observations are also reproduced numerically by using a set of reaction-diffusion equations for an activator-inhibitor model, and further analytically interpreted in terms of genuine coupling effects arising from parametric fluctuations. Within the same framework we also address situations of noise-sustained <span class="hlt">propagation</span> in subexcitable media.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22263795-investigation-guided-waves-propagation-pipe-buried-sand','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22263795-investigation-guided-waves-propagation-pipe-buried-sand"><span>Investigation of guided <span class="hlt">waves</span> <span class="hlt">propagation</span> in pipe buried in sand</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Leinov, Eli; Cawley, Peter; Lowe, Michael J.S.</p> <p></p> <p>The inspection of pipelines by guided <span class="hlt">wave</span> testing is a well-established method for the detection of corrosion defects in pipelines, and is currently used routinely in a variety of industries, e.g. petrochemical and energy. When the method is applied to pipes buried in soil, test ranges tend to be significantly compromised because of attenuation of the <span class="hlt">waves</span> caused by energy radiating into the soil. Moreover, the variability of soil conditions dictates different attenuation characteristics, which in-turn results in different, unpredictable, test ranges. We investigate experimentally the <span class="hlt">propagation</span> and attenuation characteristics of guided <span class="hlt">waves</span> in pipes buried in fine sand usingmore » a well characterized full scale experimental apparatus. The apparatus consists of an 8 inch-diameter, 5.6-meters long steel pipe embedded over 3 meters of its length in a rectangular container filled with fine sand, and an air-bladder for the application of overburden pressure. Longitudinal and torsional guided <span class="hlt">waves</span> are excited in the pipe and recorded using a transducer ring (Guided Ultrasonics Ltd). Acoustic properties of the sand are measured independently in-situ and used to make model predictions of <span class="hlt">wave</span> behavior in the buried pipe. We present the methodology and the systematic measurements of the guided <span class="hlt">waves</span> under a range of conditions, including loose and compacted sand. It is found that the application of overburden pressure modifies the compaction of the sand and increases the attenuation, and that the measurement of the acoustic properties of sand allows model prediction of the attenuation of guided <span class="hlt">waves</span> in buried pipes with a high level of confidence.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70193626','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70193626"><span><span class="hlt">Tsunami</span>-generated sediment <span class="hlt">wave</span> channels at Lake Tahoe, California-Nevada, USA</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Moore, James G.; Schweickert, Richard A.; Kitts, Christopher A.</p> <p>2014-01-01</p> <p>A gigantic ∼12 km3 landslide detached from the west wall of Lake Tahoe (California-Nevada, USA), and slid 15 km east across the lake. The splash, or <span class="hlt">tsunami</span>, from this landslide eroded Tioga-age moraines dated as 21 ka. Lake-bottom short piston cores recovered sediment as old as 12 ka that did not reach landslide deposits, thereby constraining the landslide age as 21–12 ka.Movement of the landslide splashed copious water onto the countryside and lowered the lake level ∼10 m. The sheets of water that washed back into the lake dumped their sediment load at the lowered shoreline, producing deltas that merged into delta terraces. During rapid growth, these unstable delta terraces collapsed, disaggregated, and fed turbidity currents that generated 15 subaqueous sediment <span class="hlt">wave</span> channel systems that ring the lake and descend to the lake floor at 500 m depth. Sheets of water commonly more than 2 km wide at the shoreline fed these systems. Channels of the systems contain sediment <span class="hlt">waves</span> (giant ripple marks) with maximum wavelengths of 400 m. The lower depositional aprons of the system are surfaced by sediment <span class="hlt">waves</span> with maximum wavelengths of 300 m.A remarkably similar, though smaller, contemporary sediment <span class="hlt">wave</span> channel system operates at the mouth of the Squamish River in British Columbia. The system is generated by turbidity currents that are fed by repeated growth and collapse of the active river delta. The Tahoe splash-induced backwash was briefly equivalent to more than 15 Squamish Rivers in full flood and would have decimated life in low-lying areas of the Tahoe region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1215694Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1215694Z"><span>February 27, 2010 Chilean <span class="hlt">Tsunami</span> in Pacific and its Arrival to North East Asia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zaytsev, Andrey; Pelinovsky, EfiM.; Yalciner, Ahmet C.; Ozer, Ceren; Chernov, Anton; Kostenko, Irina; Shevchenko, Georgy</p> <p>2010-05-01</p> <p>The outskirts of the fault plane broken by the strong earthquake on February 27, 2010 in Chili with a magnitude 8.8 at the 35km depth of 35.909°S, 72.733°W coordinates generated a moderate size <span class="hlt">tsunami</span>. The initial amplitude of the <span class="hlt">tsunami</span> source is not so high because of the major area of the plane was at land. The <span class="hlt">tsunami</span> <span class="hlt">waves</span> <span class="hlt">propagated</span> far distances in South and North directions to East Asia and Wet America coasts. The <span class="hlt">waves</span> are also recorded by several gauges in Pacific during its <span class="hlt">propagation</span> and arrival to coastal areas. The recorded and observed amplitudes of <span class="hlt">tsunami</span> <span class="hlt">waves</span> are important for the potential effects with the threatening amplitudes. The event also showed that a moderate size <span class="hlt">tsunami</span> can be effective even if it <span class="hlt">propagates</span> far distances in any ocean or a marginal sea. The far east coasts of Russia at North East Asia (Sakhalin, Kuriles, Kamchatka) are one of the important source (i.e. November 15, 2006, Kuril Island <span class="hlt">Tsunami</span>) and target (i.e. February, 27, 2010 Chilean <span class="hlt">tsunami</span>) areas of the Pacific <span class="hlt">tsunamis</span>. Many efforts have been spent for establishment of the monitoring system and assessment of <span class="hlt">tsunamis</span> and development of the mitigation strategies against <span class="hlt">tsunamis</span> and other hazards in the region. Development of the computer technologies provided the advances in data collection, transfer, and processing. Furthermore it also contributed new developments in computational tools and made the computer modeling to be an efficient tool in <span class="hlt">tsunami</span> warning systems. In this study the <span class="hlt">tsunami</span> numerical model NAMI DANCE Nested version is used. NAMI-DANCE solves Nonlinear form of Long <span class="hlt">Wave</span> (Shallow water) equations (with or without dispersion) using finite difference model in nested grid domains from the source to target areas in multiprocessor hardware environment. It is applied to 2010 Chilean <span class="hlt">tsunami</span> and its <span class="hlt">propagation</span> and coastal behavior at far distances near Sakhalin, Kuril and Kamchatka coasts. The main tide gauge records used in this study are from</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S52A..01B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S52A..01B"><span>Chilean <span class="hlt">Tsunami</span> Rocks the Ross Ice Shelf</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bromirski, P. D.; Gerstoft, P.; Chen, Z.; Stephen, R. A.; Diez, A.; Arcas, D.; Wiens, D.; Aster, R. C.; Nyblade, A.</p> <p>2016-12-01</p> <p>The response of the Ross Ice Shelf (RIS) to the September 16, 2015 9.3 Mb Chilean earthquake <span class="hlt">tsunami</span> (> 75 s period) and infragravity (IG) <span class="hlt">waves</span> (50 - 300 s period) were recorded by a broadband seismic array deployed on the RIS from November 2014 to November 2015. The array included two linear transects, one approximately orthogonal to the shelf front extending 430 km southward toward the grounding zone, and an east-west transect spanning the RIS roughly parallel to the front about 100 km south of the ice edge (https://scripps.ucsd.edu/centers/iceshelfvibes/). Signals generated by both the <span class="hlt">tsunami</span> and IG <span class="hlt">waves</span> were recorded at all stations on floating ice, with little ocean <span class="hlt">wave</span>-induced energy reaching stations on grounded ice. Cross-correlation and dispersion curve analyses indicate that <span class="hlt">tsunami</span> and IG <span class="hlt">wave</span>-generated signals <span class="hlt">propagate</span> across the RIS at gravity <span class="hlt">wave</span> speeds (about 70 m/s), consistent with coupled water-ice flexural-gravity <span class="hlt">waves</span> <span class="hlt">propagating</span> through the ice shelf from the north. Gravity <span class="hlt">wave</span> excitation at periods > 100 s is continuously observed during the austral winter, providing mechanical excitation of the RIS throughout the year. Horizontal displacements are typically about 3 times larger than vertical displacements, producing extensional motions that could facilitate expansion of existing fractures. The vertical and horizontal spectra in the IG band attenuate exponentially with distance from the front. <span class="hlt">Tsunami</span> model data are used to assess variability of excitation of the RIS by long period gravity <span class="hlt">waves</span>. Substantial variability across the RIS roughly parallel to the front is observed, likely resulting from a combination of gravity <span class="hlt">wave</span> amplitude variability along the front, signal attenuation, incident angle of the <span class="hlt">wave</span> forcing at the front that depends on <span class="hlt">wave</span> generation location as well as bathymetry under and north of the shelf, and water layer and ice shelf thickness and properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840025041','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840025041"><span>Numerical solutions of acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span> problems using Euler computations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hariharan, S. I.</p> <p>1984-01-01</p> <p>This paper reports solution procedures for problems arising from the study of engine inlet <span class="hlt">wave</span> <span class="hlt">propagation</span>. The first problem is the study of sound <span class="hlt">waves</span> radiated from cylindrical inlets. The second one is a quasi-one-dimensional problem to study the effect of nonlinearities and the third one is the study of nonlinearities in two dimensions. In all three problems Euler computations are done with a fourth-order explicit scheme. For the first problem results are shown in agreement with experimental data and for the second problem comparisons are made with an existing asymptotic theory. The third problem is part of an ongoing work and preliminary results are presented for this case.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SPIE10461E..1JD','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SPIE10461E..1JD"><span><span class="hlt">Propagation</span> characteristic of THz <span class="hlt">wave</span> in camouflage net material</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dong, Hailong; Wang, Jiachun; Chen, Zongsheng; Lin, Zhidan; Zhao, Dapeng; Liu, Ruihuang</p> <p>2017-10-01</p> <p>Terahertz (THz) radar system, with excellent potentials such as high-resolution and strong penetration capability, is promising in the field of anti-camouflage. Camouflage net is processed by cutting the camouflage net material, which is fabricated on pre-processing substrate by depositing coatings with camouflage abilities in different bands, such as visible, infrared and radar. In this paper, we concentrate on the <span class="hlt">propagation</span> characteristic of THz <span class="hlt">wave</span> in camouflage net material. Firstly, function and structure of camouflage net were analyzed. Then the advantage and appliance of terahertz time-domain spectroscopy (THz-TDS) was introduced. And the relevant experiments were conducted by utilizing THz-TDS. The results obtained indicate that THz <span class="hlt">wave</span> has better penetration capacity in camouflage net material, which demonstrates the feasibility of using THz radar to detect those targets covered with camouflage net.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1343000-discretizing-singular-point-sources-hyperbolic-wave-propagation-problems','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1343000-discretizing-singular-point-sources-hyperbolic-wave-propagation-problems"><span>Discretizing singular point sources in hyperbolic <span class="hlt">wave</span> <span class="hlt">propagation</span> problems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Petersson, N. Anders; O'Reilly, Ossian; Sjogreen, Bjorn; ...</p> <p>2016-06-01</p> <p>Here, we develop high order accurate source discretizations for hyperbolic <span class="hlt">wave</span> <span class="hlt">propagation</span> problems in first order formulation that are discretized by finite difference schemes. By studying the Fourier series expansions of the source discretization and the finite difference operator, we derive sufficient conditions for achieving design accuracy in the numerical solution. Only half of the conditions in Fourier space can be satisfied through moment conditions on the source discretization, and we develop smoothness conditions for satisfying the remaining accuracy conditions. The resulting source discretization has compact support in physical space, and is spread over as many grid points as themore » number of moment and smoothness conditions. In numerical experiments we demonstrate high order of accuracy in the numerical solution of the 1-D advection equation (both in the interior and near a boundary), the 3-D elastic <span class="hlt">wave</span> equation, and the 3-D linearized Euler equations.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19770034971&hterms=corkscrew&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dcorkscrew','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19770034971&hterms=corkscrew&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dcorkscrew"><span>Measurements on <span class="hlt">wave</span> <span class="hlt">propagation</span> characteristics of spiraling electron beams</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Singh, A.; Getty, W. D.</p> <p>1976-01-01</p> <p>Dispersion characteristics of cyclotron-harmonic <span class="hlt">waves</span> <span class="hlt">propagating</span> on a neutralized spiraling electron beam immersed in a uniform axial magnetic field are studied experimentally. The experimental setup consisted of a vacuum system, an electron-gun corkscrew assembly which produces a 110-eV beam with the desired delta-function velocity distribution, a measurement region where a microwave signal is injected onto the beam to measure wavelengths, and a velocity analyzer for measuring the axial electron velocity. Results of wavelength measurements made at beam currents of 0.15, 1.0, and 2.0 mA are compared with calculated values, and undesirable effects produced by increasing the beam current are discussed. It is concluded that a suitable electron beam for studies of cyclotron-harmonic <span class="hlt">waves</span> can be generated by the corkscrew device.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16797665','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16797665"><span>Acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span> in high-pressure system.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Foldyna, Josef; Sitek, Libor; Habán, Vladimír</p> <p>2006-12-22</p> <p>Recently, substantial attention is paid to the development of methods of generation of pulsations in high-pressure systems to produce pulsating high-speed water jets. The reason is that the introduction of pulsations into the water jets enables to increase their cutting efficiency due to the fact that the impact pressure (so-called water-hammer pressure) generated by an impact of slug of water on the target material is considerably higher than the stagnation pressure generated by corresponding continuous jet. Special method of pulsating jet generation was developed and tested extensively under the laboratory conditions at the Institute of Geonics in Ostrava. The method is based on the action of acoustic transducer on the pressure liquid and transmission of generated acoustic <span class="hlt">waves</span> via pressure system to the nozzle. The purpose of the paper is to present results obtained during the research oriented at the determination of acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span> in high-pressure system. The final objective of the research is to solve the problem of transmission of acoustic <span class="hlt">waves</span> through high-pressure water to generate pulsating jet effectively even at larger distances from the acoustic source. In order to be able to simulate numerically acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span> in the system, it is necessary among others to determine dependence of the sound speed and second kinematical viscosity on operating pressure. Method of determination of the second kinematical viscosity and speed of sound in liquid using modal analysis of response of the tube filled with liquid to the impact was developed. The response was measured by pressure sensors placed at both ends of the tube. Results obtained and presented in the paper indicate good agreement between experimental data and values of speed of sound calculated from so-called "UNESCO equation". They also show that the value of the second kinematical viscosity of water depends on the pressure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MPLB...3140075Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MPLB...3140075Y"><span><span class="hlt">Propagation</span> characteristics of ultrasonic guided <span class="hlt">waves</span> in continuously welded rail</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yao, Wenqing; Sheng, Fuwei; Wei, Xiaoyuan; Zhang, Lei; Yang, Yuan</p> <p>2017-07-01</p> <p>Rail defects cause numerous railway accidents. Trains are derailed and serious consequences often occur. Compared to traditional bulk <span class="hlt">wave</span> testing, ultrasonic guided <span class="hlt">waves</span> (UGWs) can provide larger monitoring ranges and complete coverage of the waveguide cross-section. These advantages are of significant importance for the non-destructive testing (NDT) of the continuously welded rail, and the technique is therefore widely used in high-speed railways. UGWs in continuous welded rail (CWR) and their <span class="hlt">propagation</span> characteristics have been discussed in this paper. Finite element methods (FEMs) were used to accomplish a vibration modal analysis, which is extended by a subsequent dispersion analysis. <span class="hlt">Wave</span> structure features were illustrated by displacement profiles. It was concluded that guided <span class="hlt">waves</span> have the ability to detect defects in the rail via choice of proper mode and frequency. Additionally, thermal conduction that is caused by temperature variation in the rail is added into modeling and simulation. The results indicated that unbalanced thermal distribution may lead to the attenuation of UGWs in the rail.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1994sri..reptQ....W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1994sri..reptQ....W"><span>Plasma and radio <span class="hlt">waves</span> from Neptune: Source mechanisms and <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wong, H. K.</p> <p>1994-03-01</p> <p>This report summarizes results obtained through the support of NASA Grant NAGW-2412. The objective of this project is to conduct a comprehensive investigation of the radio <span class="hlt">wave</span> emission observed by the planetary radio astronomy (PRA) instrument on board Voyager 2 as if flew by Neptune. This study has included data analysis, theoretical and numerical calculations, ray tracing, and modeling to determine the possible source mechanism(s) and locations of the Neptune radio emissions. We have completed four papers, which are included in the appendix. The paper 'Modeling of Whistler Ray Paths in the Magnetosphere of Neptune' investigated the <span class="hlt">propagation</span> and dispersion of lighting-generated whistler in the magnetosphere of Neptune by using three dimensional ray tracing. The two papers 'Numerical Simulations of Bursty Radio Emissions from Planetary Magnetospheres' and 'Numerical Simulations of Bursty Planetary Radio Emissions' employed numerical simulations to investigate an alternate source mechanism of bursty radio emissions in addition to the cyclotron maser instability. We have also studied the possible generation of Z and whistler mode <span class="hlt">waves</span> by the temperature anisotropic beam instability and the result was published in 'Electron Cyclotron <span class="hlt">Wave</span> Generation by Relativistic Electrons.' Besides the aforementioned studies, we have also collaborated with members of the PRA team to investigate various aspects of the radio <span class="hlt">wave</span> data. Two papers have been submitted for publication and the abstracts of these papers are also listed in the appendix.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1333912-wave-speed-propagation-measurements-highly-attenuative-heated-materials','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1333912-wave-speed-propagation-measurements-highly-attenuative-heated-materials"><span><span class="hlt">Wave</span> speed <span class="hlt">propagation</span> measurements on highly attenuative heated materials</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Moore, David G.; Ober, Curtis C.; Rodacy, Phil J.; ...</p> <p>2015-09-19</p> <p>Ultrasonic <span class="hlt">wave</span> <span class="hlt">propagation</span> decreases as a material is heated. Two factors that can characterize material properties are changes in <span class="hlt">wave</span> speed and energy loss from interactions within the media. Relatively small variations in velocity and attenuation can detect significant differences in microstructures. This paper discusses an overview of experimental techniques that document the changes within a highly attenuative material as it is either being heated or cooled from 25°C to 90°C. The experimental set-up utilizes ultrasonic probes in a through-transmission configuration. The waveforms are recorded and analyzed during thermal experiments. To complement the ultrasonic data, a Discontinuous-Galerkin Model (DGM) wasmore » also created which uses unstructured meshes and documents how <span class="hlt">waves</span> travel in these anisotropic media. This numerical method solves particle motion travel using partial differential equations and outputs a <span class="hlt">wave</span> trace per unit time. As a result, both experimental and analytical data are compared and presented.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..DFDA37002M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..DFDA37002M"><span>Fully resolved simulations of expansion <span class="hlt">waves</span> <span class="hlt">propagating</span> into particle beds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marjanovic, Goran; Hackl, Jason; Annamalai, Subramanian; Jackson, Thomas; Balachandar, S.</p> <p>2017-11-01</p> <p>There is a tremendous amount of research that has been done on compression <span class="hlt">waves</span> and shock <span class="hlt">waves</span> moving over particles but very little concerning expansion <span class="hlt">waves</span>. Using 3-D direct numerical simulations, this study will explore expansion <span class="hlt">waves</span> <span class="hlt">propagating</span> into fully resolved particle beds of varying volume fractions and geometric arrangements. The objectives of these simulations are as follows: 1) To fully resolve all (1-way coupled) forces on the particles in a time varying flow and 2) to verify state-of-the-art drag models for such complex flows. We will explore a range of volume fractions, from very low ones that are similar to single particle flows, to higher ones where nozzling effects are observed between neighboring particles. Further, we will explore two geometric arrangements: body centered cubic and face centered cubic. We will quantify the effects that volume fraction and geometric arrangement plays on the drag forces and flow fields experienced by the particles. These results will then be compared to theoretical predictions from a model based on the generalized Faxen's theorem. This work was supported in part by the U.S. Department of Energy under the Predictive Science Academic Alliance Program, under Contract No. DE-NA0002378.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940028597','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940028597"><span>Plasma and radio <span class="hlt">waves</span> from Neptune: Source mechanisms and <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wong, H. K.</p> <p>1994-01-01</p> <p>This report summarizes results obtained through the support of NASA Grant NAGW-2412. The objective of this project is to conduct a comprehensive investigation of the radio <span class="hlt">wave</span> emission observed by the planetary radio astronomy (PRA) instrument on board Voyager 2 as if flew by Neptune. This study has included data analysis, theoretical and numerical calculations, ray tracing, and modeling to determine the possible source mechanism(s) and locations of the Neptune radio emissions. We have completed four papers, which are included in the appendix. The paper 'Modeling of Whistler Ray Paths in the Magnetosphere of Neptune' investigated the <span class="hlt">propagation</span> and dispersion of lighting-generated whistler in the magnetosphere of Neptune by using three dimensional ray tracing. The two papers 'Numerical Simulations of Bursty Radio Emissions from Planetary Magnetospheres' and 'Numerical Simulations of Bursty Planetary Radio Emissions' employed numerical simulations to investigate an alternate source mechanism of bursty radio emissions in addition to the cyclotron maser instability. We have also studied the possible generation of Z and whistler mode <span class="hlt">waves</span> by the temperature anisotropic beam instability and the result was published in 'Electron Cyclotron <span class="hlt">Wave</span> Generation by Relativistic Electrons.' Besides the aforementioned studies, we have also collaborated with members of the PRA team to investigate various aspects of the radio <span class="hlt">wave</span> data. Two papers have been submitted for publication and the abstracts of these papers are also listed in the appendix.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70000187','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70000187"><span>Coarse-clast ridge complexes of the Caribbean: A preliminary basis for distinguishing <span class="hlt">tsunami</span> and storm-<span class="hlt">wave</span> origins</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Morton, R.A.; Richmond, B.M.; Jaffe, B.E.; Gelfenbaum, G.</p> <p>2008-01-01</p> <p>Coastal gravel-ridge complexes deposited on islands in the Caribbean Sea are recorders of past extreme-<span class="hlt">wave</span> events that could be associated with either <span class="hlt">tsunamis</span> or hurricanes. The ridge complexes of Bonaire, Jamaica, Puerto Rico (Isla de Mona), and Guadeloupe consist of polymodal clasts ranging in size from sand to coarse boulders that are derived from the adjacent coral reefs or subjacent rock platforms. Ridge-complex morphologies and crest elevations are largely controlled by availability of sediments, clast sizes, and heights of <span class="hlt">wave</span> runup. The ridge complexes are internally organized, display textural sorting and a broad range of ages including historical events. Some display seaward-dipping beds and ridge-and-swale topography, and some terminate in fans or steep avalanche slopes. Together, the morphologic, sedimentologic, lithostratigraphic, and chronostratigraphic evidence indicates that shore-parallet ridge complexes composed of gravel and sand that are tens of meters wide and several meters thick are primarily storm-constructed features that have accumulated for a few centuries or millennia as a result of multiple high-frequency intense-<span class="hlt">wave</span> events. They are not entirely the result of one or a few <span class="hlt">tsunamis</span> as recently reported. <span class="hlt">Tsunami</span> deposition may account for some of the lateral ridge-complex accretion or boulder fields and isolated blocks that are associated with the ridge complexes. Copyright ?? 2008, SEPM (Society for Sedimentary Geology).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014RMRE...47.1393G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014RMRE...47.1393G"><span>Numerical Homogenization of Jointed Rock Masses Using <span class="hlt">Wave</span> <span class="hlt">Propagation</span> Simulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gasmi, Hatem; Hamdi, Essaïeb; Bouden Romdhane, Nejla</p> <p>2014-07-01</p> <p>Homogenization in fractured rock analyses is essentially based on the calculation of equivalent elastic parameters. In this paper, a new numerical homogenization method that was programmed by means of a MATLAB code, called HLA-Dissim, is presented. The developed approach simulates a discontinuity network of real rock masses based on the International Society of Rock Mechanics (ISRM) scanline field mapping methodology. Then, it evaluates a series of classic joint parameters to characterize density (RQD, specific length of discontinuities). A pulse <span class="hlt">wave</span>, characterized by its amplitude, central frequency, and duration, is <span class="hlt">propagated</span> from a source point to a receiver point of the simulated jointed rock mass using a complex recursive method for evaluating the transmission and reflection coefficient for each simulated discontinuity. The seismic parameters, such as delay, velocity, and attenuation, are then calculated. Finally, the equivalent medium model parameters of the rock mass are computed numerically while taking into account the natural discontinuity distribution. This methodology was applied to 17 bench fronts from six aggregate quarries located in Tunisia, Spain, Austria, and Sweden. It allowed characterizing the rock mass discontinuity network, the resulting seismic performance, and the equivalent medium stiffness. The relationship between the equivalent Young's modulus and rock discontinuity parameters was also analyzed. For these different bench fronts, the proposed numerical approach was also compared to several empirical formulas, based on RQD and fracture density values, published in previous research studies, showing its usefulness and efficiency in estimating rapidly the Young's modulus of equivalent medium for <span class="hlt">wave</span> <span class="hlt">propagation</span> analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SPIE10407E..09B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SPIE10407E..09B"><span>Rigorous vector <span class="hlt">wave</span> <span class="hlt">propagation</span> for arbitrary flat media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bos, Steven P.; Haffert, Sebastiaan Y.; Keller, Christoph U.</p> <p>2017-08-01</p> <p>Precise modelling of the (off-axis) point spread function (PSF) to identify geometrical and polarization aberrations is important for many optical systems. In order to characterise the PSF of the system in all Stokes parameters, an end-to-end simulation of the system has to be performed in which Maxwell's equations are rigorously solved. We present the first results of a python code that we are developing to perform multiscale end-to-end <span class="hlt">wave</span> <span class="hlt">propagation</span> simulations that include all relevant physics. Currently we can handle plane-parallel near- and far-field vector diffraction effects of <span class="hlt">propagating</span> <span class="hlt">waves</span> in homogeneous isotropic and anisotropic materials, refraction and reflection of flat parallel surfaces, interference effects in thin films and unpolarized light. We show that the code has a numerical precision on the order of 10-16 for non-absorbing isotropic and anisotropic materials. For absorbing materials the precision is on the order of 10-8. The capabilities of the code are demonstrated by simulating a converging beam reflecting from a flat aluminium mirror at normal incidence.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002EGSGA..27.1427S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002EGSGA..27.1427S"><span>Numerical Simulations of Upstream <span class="hlt">Propagating</span> Solitary <span class="hlt">Waves</span> and <span class="hlt">Wave</span> Breaking In A Stratified Fjord</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stastna, M.; Peltier, W. R.</p> <p></p> <p>In this talk we will discuss ongoing numerical modeling of the flow of a stratified fluid over large scale topography motivated by observations in Knight Inlet, a fjord in British Columbia, Canada. After briefly surveying the work done on the topic in the past we will discuss our latest set of simulations in which we have observed the gener- ation and breaking of three different types of nonlinear internal <span class="hlt">waves</span> in the lee of the sill topography. The first type of <span class="hlt">wave</span> observed is a large lee <span class="hlt">wave</span> in the weakly strat- ified main portion of the water column, The second is an upward <span class="hlt">propagating</span> internal <span class="hlt">wave</span> forced by topography that breaks in the strong, near-surface pycnocline. The third is a train of upstream <span class="hlt">propagating</span> solitary <span class="hlt">waves</span> that, in certain circumstances, form as breaking <span class="hlt">waves</span> consisting of a nearly solitary <span class="hlt">wave</span> envelope and a highly unsteady core near the surface. Time premitting, we will comment on the implications of these results for our long term goal of quantifying tidally driven mixing in Knight Inlet.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=mechanical+AND+properties&pg=3&id=EJ860670','ERIC'); return false;" href="https://eric.ed.gov/?q=mechanical+AND+properties&pg=3&id=EJ860670"><span>A Problem-Based Approach to Elastic <span class="hlt">Wave</span> <span class="hlt">Propagation</span>: The Role of Constraints</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Fazio, Claudio; Guastella, Ivan; Tarantino, Giovanni</p> <p>2009-01-01</p> <p>A problem-based approach to the teaching of mechanical <span class="hlt">wave</span> <span class="hlt">propagation</span>, focused on observation and measurement of <span class="hlt">wave</span> properties in solids and on modelling of these properties, is presented. In particular, some experimental results, originally aimed at measuring the <span class="hlt">propagation</span> speed of sound <span class="hlt">waves</span> in metallic rods, are used in order to deepen…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014cosp...40E.980G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014cosp...40E.980G"><span><span class="hlt">Propagation</span> of stationary Rossby <span class="hlt">waves</span> in the Martian lower atmosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ghosh, Priyanka; Thokuluwa, Ramkumar</p> <p></p> <p>The Martian lower atmospheric (-1.5 km to 29.3 km) temperature, measured by radio occultation technique during the Mars Global Surveyor (MGS) mission launched by US in November 1996, at the Northern winter hemispheric latitude of about 63(°) N clearly shows a statistically significant (above 95 percent confidential level white noise) and strong 3.5-day oscillation during 1-10 January 2006. This strong signal occurs in the longitudinal sectors of 0-30(°) E and 190-230(°) E but statistically insignificant in almost all the other longitudes. This 180 degree separation between the two peaks of occurrence of strong 3.5 day oscillation indicates that this may be associated with zonal <span class="hlt">wave</span> number 2 structure global scale <span class="hlt">wave</span>. At the lowest height of -1.5 km, the power observed in the longitude of 0-30(°) E is 50 K (2) and it increased gradually to the maximum power of 130 K (2) at the height of 0.8 - 1.7 km. Above this height, the power decreased monotonously and gradually to insignificant level at the height of 3.7 km (20 K (2) ). This gradual decrease of power above the height of 1.7 km indicates that radiative damping (infra red cooling due to large abundance of CO _{2} molecules and dust particles) would have played an important role in the dissipation of <span class="hlt">waves</span>. The height and longitudinal profiles of phase of the 3.5-day <span class="hlt">wave</span> indicate that this <span class="hlt">wave</span> is a vertically standing and eastward <span class="hlt">propagating</span> planetary <span class="hlt">wave</span> respectively. Since the statistically significant spectral amplitude occurs near the high topography structures, it seems that the <span class="hlt">wave</span> is generated by flows over the topography. In the Northern winter, it is possible that the large gradient of temperature between the low and high latitudes would lead to flow of winds from the tropical to polar latitudes. Due to the Coriolis effect, this flow would in turn move towards the right and incite <span class="hlt">wave</span> generation when the air flows over the high topographic structures. This lead to speculate that the observed 3</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPC.1821h0002B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPC.1821h0002B"><span>Ultrasound shear <span class="hlt">wave</span> simulation based on nonlinear <span class="hlt">wave</span> <span class="hlt">propagation</span> and Wigner-Ville Distribution analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bidari, Pooya Sobhe; Alirezaie, Javad; Tavakkoli, Jahan</p> <p>2017-03-01</p> <p>This paper presents a method for modeling and simulation of shear <span class="hlt">wave</span> generation from a nonlinear Acoustic Radiation Force Impulse (ARFI) that is considered as a distributed force applied at the focal region of a HIFU transducer radiating in nonlinear regime. The shear <span class="hlt">wave</span> <span class="hlt">propagation</span> is simulated by solving the Navier's equation from the distributed nonlinear ARFI as the source of the shear <span class="hlt">wave</span>. Then, the Wigner-Ville Distribution (WVD) as a time-frequency analysis method is used to detect the shear <span class="hlt">wave</span> at different local points in the region of interest. The WVD results in an estimation of the shear <span class="hlt">wave</span> time of arrival, its mean frequency and local attenuation which can be utilized to estimate medium's shear modulus and shear viscosity using the Voigt model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AAS...210.9113S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AAS...210.9113S"><span>Coronal Seismology: The Search for <span class="hlt">Propagating</span> <span class="hlt">Waves</span> in Coronal Loops</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schad, Thomas A.; Seeley, D.; Keil, S. L.; Tomczyk, S.</p> <p>2007-05-01</p> <p>We report on Doppler observations of the solar corona obtained in the Fe XeXIII 1074.7nm coronal emission line with the HAO Coronal Multi-Channel Polarimeter (CoMP) mounted on the NSO Coronal One Shot coronagraph located in the Hilltop Facility of NSO/Sacramento Peak. The COMP is a tunable filtergraph instrument that records the entire corona from the edge of the occulting disk at approximately 1.03 Rsun out to 1.4 Rsun with a spatial resolution of about 4” x 4”. COMP can be rapidly scanned through the spectral line while recording orthogonal states of linear and circular polarization. The two dimensional spatial resolution allows us to correlate temporal fluctuations observed in one part of the corona with those seen at other locations, in particular along coronal loops. Using cross spectral analysis we find that the observations reveal upward <span class="hlt">propagating</span> <span class="hlt">waves</span> that are characterized by Doppler shifts with rms velocities of 0.3 km/s, peak <span class="hlt">wave</span> power in the 3-5 mHz frequency range, and phase speeds 1-3 Mm/s. The <span class="hlt">wave</span> trajectories are consistent with the direction of the magnetic field inferred from the linear polarization measurements. We discuss the phase and coherence of these <span class="hlt">waves</span> as a function of height in the corona and relate our findings to previous observations. The observed <span class="hlt">waves</span> appear to be Alfvenic in character. "Thomas Schad was supported through the National Solar Observatory Research Experiences for Undergraduate (REU) site program, which is co-funded by the Department of Defense in partnership with the National Science Foundation REU Program." Daniel Seeley was supported through the National Solar Observatory Research Experience for Teachers (RET) site program, which is funded by the National Science Foundation RET program.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRC..122.9605W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRC..122.9605W"><span>How Do Tides and <span class="hlt">Tsunamis</span> Interact in a Highly Energetic Channel? The Case of Canal Chacao, Chile</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Winckler, Patricio; Sepúlveda, Ignacio; Aron, Felipe; Contreras-López, Manuel</p> <p>2017-12-01</p> <p>This study aims at understanding the role of tidal level, speed, and direction in <span class="hlt">tsunami</span> <span class="hlt">propagation</span> in highly energetic tidal channels. The main goal is to comprehend whether tide-<span class="hlt">tsunami</span> interactions enhance/reduce elevation, currents speeds, and arrival times, when compared to pure <span class="hlt">tsunami</span> models and to simulations in which tides and <span class="hlt">tsunamis</span> are linearly superimposed. We designed various numerical experiments to compute the <span class="hlt">tsunami</span> <span class="hlt">propagation</span> along Canal Chacao, a highly energetic channel in the Chilean Patagonia lying on a subduction margin prone to megathrust earthquakes. Three modeling approaches were implemented under the same seismic scenario: a <span class="hlt">tsunami</span> model with a constant tide level, a series of six composite models in which independent tide and <span class="hlt">tsunami</span> simulations are linearly superimposed, and a series of six tide-<span class="hlt">tsunami</span> nonlinear interaction models (full models). We found that hydrodynamic patterns differ significantly among approaches, being the composite and full models sensitive to both the tidal phase at which the <span class="hlt">tsunami</span> is triggered and the local depth of the channel. When compared to full models, composite models adequately predicted the maximum surface elevation, but largely overestimated currents. The amplitude and arrival time of the <span class="hlt">tsunami</span>-leading <span class="hlt">wave</span> computed with the full model was found to be strongly dependent on the direction of the tidal current and less responsive to the tide level and the tidal current speed. These outcomes emphasize the importance of addressing more carefully the interactions of tides and <span class="hlt">tsunamis</span> on hazard assessment studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PlST...18..798W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PlST...18..798W"><span>FDTD Simulation on Terahertz <span class="hlt">Waves</span> <span class="hlt">Propagation</span> Through a Dusty Plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Maoyan; Zhang, Meng; Li, Guiping; Jiang, Baojun; Zhang, Xiaochuan; Xu, Jun</p> <p>2016-08-01</p> <p>The frequency dependent permittivity for dusty plasmas is provided by introducing the charging response factor and charge relaxation rate of airborne particles. The field equations that describe the characteristics of Terahertz (THz) <span class="hlt">waves</span> <span class="hlt">propagation</span> in a dusty plasma sheath are derived and discretized on the basis of the auxiliary differential equation (ADE) in the finite difference time domain (FDTD) method. Compared with numerical solutions in reference, the accuracy for the ADE FDTD method is validated. The reflection property of the metal Aluminum interlayer of the sheath at THz frequencies is discussed. The effects of the thickness, effective collision frequency, airborne particle density, and charge relaxation rate of airborne particles on the electromagnetic properties of Terahertz <span class="hlt">waves</span> through a dusty plasma slab are investigated. Finally, some potential applications for Terahertz <span class="hlt">waves</span> in information and communication are analyzed. supported by National Natural Science Foundation of China (Nos. 41104097, 11504252, 61201007, 41304119), the Fundamental Research Funds for the Central Universities (Nos. ZYGX2015J039, ZYGX2015J041), and the Specialized Research Fund for the Doctoral Program of Higher Education of China (No. 20120185120012)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.6894S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.6894S"><span>Frequency Domain Modelling of Electromagnetic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Layered Media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schmidt, Felix; Lünenschloss, Peter; Mai, Juliane; Wagner, Norman; Töpfer, Hannes; Bumberger, Jan</p> <p>2016-04-01</p> <p>The amount of water in porous media such as soils and rocks is a key parameter when water resources are under investigation. Especially the quantitative spatial distribution and temporal evolution of water contents in soil formations are needed. In high frequency electromagnetic applications soil water content is quantitatively derived from the <span class="hlt">propagation</span> behavior of electromagnetic <span class="hlt">waves</span> along waveguides embedded in soil formations. The spatial distribution of the dielectric material properties along the waveguide can be estimated by numerical solving of the inverse problem based on the full <span class="hlt">wave</span> forward model in time or frequency domain. However, current approaches mostly neglect or approximate the frequency dependence of the electromagnetic material properties of transfer function of the waveguide. As a first prove of concept a full two port broadband frequency domain forward model for <span class="hlt">propagation</span> of transverse electromagnetic (TEM) <span class="hlt">waves</span> in coaxial waveguide has been implemented. It is based on the <span class="hlt">propagation</span> matrix approach for layered transmission line sections. Depending on the complexity of the material different models for the frequency dependent complex permittivity were applied. For the validation of the model a broadband frequency domain measurement with network analyzer technique was used. The measurement is based on a 20 cm long 50 Ohm 20/46 coaxial transmission line cell considering inhomogeneous material distributions. This approach allows (i) an increase of the waveguide calibration accuracy in comparison to conventional TDR based technique and (ii) the consideration of the broadband permittivity spectrum of the porous material. In order to systematic analyze the model, theoretical results were compared with measurements as well as 3D broadband finite element modeling of homogeneous and layered media in the coaxial transmission line cell. Defined standards (Teflon, dry glass beads, de-ionized water) were placed inside the line as the dielectric</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.6544S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.6544S"><span>Frequency Domain Modelling of Electromagnetic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Layered Media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schmidt, Felix; Wagner, Norman; Lünenschloß, Peter; Toepfer, Hannes; Dietrich, Peter; Kaliorias, Andreas; Bumberger, Jan</p> <p>2015-04-01</p> <p>The amount of water in porous media such as soils and rocks is a key parameter when water resources are under investigation. Especially the quantitative spatial distribution and temporal evolution of water contents in soil formations are needed. In high frequency electromagnetic applications soil water content is quantitatively derived from the <span class="hlt">propagation</span> behavior of electromagnetic <span class="hlt">waves</span> along waveguides embedded in soil formations. The spatial distribution of the dielectric material properties along the waveguide can be estimated by numerical solving of the inverse problem based on the full <span class="hlt">wave</span> forward model in time or frequency domain. However, current approaches mostly neglect or approximate the frequency dependence of the electromagnetic material properties of transfer function of the waveguide. As a first prove of concept a full two port broadband frequency domain forward model for <span class="hlt">propagation</span> of transverse electromagnetic (TEM) <span class="hlt">waves</span> in coaxial waveguide has been implemented. It is based on the <span class="hlt">propagation</span> matrix approach for layered transmission line sections Depending on the complexity of the material different models for the frequency dependent complex permittivity were applied. For the validation of the model a broadband frequency domain measurement with network analyzer technique was used. The measurement is based on a 20 cm long 50 Ohm 20/46 coaxial transmission line cell considering inhomogeneous material distributions. This approach allows (i) an increase of the waveguide calibration accuracy in comparison to conventional TDR based technique and (ii) the consideration of the broadband permittivity spectrum of the porous material. In order to systematic analyze the model, theoretical results were compared with measurements as well as 3D broadband finite element modeling of homogeneous and layered media in the coaxial transmission line cell. Defined standards (Teflon, dry glass beads, de-ionized water) were placed inside the line as the dielectric</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16123264','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16123264"><span>The global reach of the 26 December 2004 Sumatra <span class="hlt">tsunami</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Titov, Vasily; Rabinovich, Alexander B; Mofjeld, Harold O; Thomson, Richard E; González, Frank I</p> <p>2005-09-23</p> <p>Numerical model simulations, combined with tide-gauge and satellite altimetry data, reveal that <span class="hlt">wave</span> amplitudes, directionality, and global <span class="hlt">propagation</span> patterns of the 26 December 2004 Sumatra <span class="hlt">tsunami</span> were primarily determined by the orientation and intensity of the offshore seismic line source and subsequently by the trapping effect of mid-ocean ridge topographic waveguides.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMOS43D1340U','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMOS43D1340U"><span>Solomon Islands 2007 <span class="hlt">Tsunami</span> Near-Field Modeling and Source Earthquake Deformation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Uslu, B.; Wei, Y.; Fritz, H.; Titov, V.; Chamberlin, C.</p> <p>2008-12-01</p> <p>The earthquake of 1 April 2007 left behind momentous footages of crust rupture and <span class="hlt">tsunami</span> impact along the coastline of Solomon Islands (Fritz and Kalligeris, 2008; Taylor et al., 2008; McAdoo et al., 2008; PARI, 2008), while the undisturbed <span class="hlt">tsunami</span> signals were also recorded at nearby deep-ocean tsunameters and coastal tide stations. These multi-dimensional measurements provide valuable datasets to tackle the challenging aspects at the <span class="hlt">tsunami</span> source directly by inversion from tsunameter records in real time (available in a time frame of minutes), and its relationship with the seismic source derived either from the seismometer records (available in a time frame of hours or days) or from the crust rupture measurements (available in a time frame of months or years). The <span class="hlt">tsunami</span> measurements in the near field, including the complex vertical crust motion and <span class="hlt">tsunami</span> runup, are particularly critical to help interpreting the <span class="hlt">tsunami</span> source. This study develops high-resolution inundation models for the Solomon Islands to compute the near-field <span class="hlt">tsunami</span> impact. Using these models, this research compares the tsunameter-derived <span class="hlt">tsunami</span> source with the seismic-derived earthquake sources from comprehensive perceptions, including vertical uplift and subsidence, <span class="hlt">tsunami</span> runup heights and their distributional pattern among the islands, deep-ocean tsunameter measurements, and near- and far-field tide gauge records. The present study stresses the significance of the <span class="hlt">tsunami</span> magnitude, source location, bathymetry and topography in accurately modeling the generation, <span class="hlt">propagation</span> and inundation of the <span class="hlt">tsunami</span> <span class="hlt">waves</span>. This study highlights the accuracy and efficiency of the tsunameter-derived <span class="hlt">tsunami</span> source in modeling the near-field <span class="hlt">tsunami</span> impact. As the high- resolution models developed in this study will become part of NOAA's <span class="hlt">tsunami</span> forecast system, these results also suggest expanding the system for potential applications in <span class="hlt">tsunami</span> hazard assessment, search and rescue operations</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70026083','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70026083"><span><span class="hlt">Tsunamis</span> generated by subaerial mass flows</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Walder, S.J.; Watts, P.; Sorensen, O.E.; Janssen, K.</p> <p>2003-01-01</p> <p><span class="hlt">Tsunamis</span> generated in lakes and reservoirs by subaerial mass flows pose distinctive problems for hazards assessment because the domain of interest is commonly the "near field," beyond the zone of complex splashing but close enough to the source that <span class="hlt">wave</span> <span class="hlt">propagation</span> effects are not predominant. Scaling analysis of the equations governing water <span class="hlt">wave</span> <span class="hlt">propagation</span> shows that near-field <span class="hlt">wave</span> amplitude and wavelength should depend on certain measures of mass flow dynamics and volume. The scaling analysis motivates a successful collapse (in dimensionless space) of data from two distinct sets of experiments with solid block "<span class="hlt">wave</span> makers." To first order, <span class="hlt">wave</span> amplitude/water depth is a simple function of the ratio of dimensionless <span class="hlt">wave</span> maker travel time to dimensionless <span class="hlt">wave</span> maker volume per unit width. <span class="hlt">Wave</span> amplitude data from previous laboratory investigations with both rigid and deformable <span class="hlt">wave</span> makers follow the same trend in dimensionless parameter space as our own data. The characteristic wavelength/water depth for all our experiments is simply proportional to dimensionless <span class="hlt">wave</span> maker travel time, which is itself given approximately by a simple function of <span class="hlt">wave</span> maker length/water depth. <span class="hlt">Wave</span> maker shape and rigidity do not otherwise influence <span class="hlt">wave</span> features. Application of the amplitude scaling relation to several historical events yields "predicted" near-field <span class="hlt">wave</span> amplitudes in reasonable agreement with measurements and observations. Together, the scaling relations for near-field amplitude, wavelength, and submerged travel time provide key inputs necessary for computational <span class="hlt">wave</span> <span class="hlt">propagation</span> and hazards assessment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19740013685','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19740013685"><span>The influence of polarization on millimeter <span class="hlt">wave</span> <span class="hlt">propagation</span> through rain</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bostian, C. W.; Stutzman, W. L.; Wiley, P. H.; Marshall, R. E.</p> <p>1974-01-01</p> <p>The influence of polarization on millimeter <span class="hlt">wave</span> <span class="hlt">propagation</span> through rain is investigated. The experimental equipment consisted of a 1.43 km line-of-sight path with 4-foot diameter dual-polarized parabolic reflector antennas at each end. Linearly polarized 17.65 GHz signals were transmitted with the electric field vectors at plus 45 degrees and minus 45 degrees from the vertical. These polarizations were initially chosen to maximize the measured depolarization at any given rainfall rate. Later it was discovered that the cross polarization levels measured with plus or minus 45 degree linearly polarized signals are theoretically the least sensitive to variations in drop canting angle and this choice of polarization reduces the scatter in the data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPhA...50E5102L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPhA...50E5102L"><span>A functional renormalization method for <span class="hlt">wave</span> <span class="hlt">propagation</span> in random media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lamagna, Federico; Calzetta, Esteban</p> <p>2017-08-01</p> <p>We develop the exact renormalization group approach as a way to evaluate the effective speed of the <span class="hlt">propagation</span> of a scalar <span class="hlt">wave</span> in a medium with random inhomogeneities. We use the Martin-Siggia-Rose formalism to translate the problem into a non equilibrium field theory one, and then consider a sequence of models with a progressively lower infrared cutoff; in the limit where the cutoff is removed we recover the problem of interest. As a test of the formalism, we compute the effective dielectric constant of an homogeneous medium interspersed with randomly located, interpenetrating bubbles. A simple approximation to the renormalization group equations turns out to be equivalent to a self-consistent two-loops evaluation of the effective dielectric constant.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4297358','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4297358"><span>Novel <span class="hlt">wave</span> intensity analysis of arterial pulse <span class="hlt">wave</span> <span class="hlt">propagation</span> accounting for peripheral reflections</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Alastruey, Jordi; Hunt, Anthony A E; Weinberg, Peter D</p> <p>2014-01-01</p> <p>We present a novel analysis of arterial pulse <span class="hlt">wave</span> <span class="hlt">propagation</span> that combines traditional <span class="hlt">wave</span> intensity analysis with identification of Windkessel pressures to account for the effect on the pressure waveform of peripheral <span class="hlt">wave</span> reflections. Using haemodynamic data measured in vivo in the rabbit or generated numerically in models of human compliant vessels, we show that traditional <span class="hlt">wave</span> intensity analysis identifies the timing, direction and magnitude of the predominant <span class="hlt">waves</span> that shape aortic pressure and flow waveforms in systole, but fails to identify the effect of peripheral reflections. These reflections persist for several cardiac cycles and make up most of the pressure waveform, especially in diastole and early systole. Ignoring peripheral reflections leads to an erroneous indication of a reflection-free period in early systole and additional error in the estimates of (i) pulse <span class="hlt">wave</span> velocity at the ascending aorta given by the PU–loop method (9.5% error) and (ii) transit time to a dominant reflection site calculated from the <span class="hlt">wave</span> intensity profile (27% error). These errors decreased to 1.3% and 10%, respectively, when accounting for peripheral reflections. Using our new analysis, we investigate the effect of vessel compliance and peripheral resistance on <span class="hlt">wave</span> intensity, peripheral reflections and reflections originating in previous cardiac cycles. PMID:24132888</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19810009558','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19810009558"><span>Radio-<span class="hlt">wave</span> <span class="hlt">propagation</span> for space communications systems</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ippolito, L. J.</p> <p>1981-01-01</p> <p>The most recent information on the effects of Earth's atmosphere on space communications systems is reviewed. The design and reliable operation of satellite systems that provide the many applications in space which rely on the transmission of radio <span class="hlt">waves</span> for communications and scientific purposes are dependent on the <span class="hlt">propagation</span> characteristics of the transmission path. The presence of atmospheric gases, clouds, fog, precipitation, and turbulence causes uncontrolled variations in the signal characteristics. These variations can result in a reduction of the quality and reliability of the transmitted information. Models and other techniques are used in the prediction of atmospheric effects as influenced by frequency, geography, elevation angle, and type of transmission. Recent data on performance characteristics obtained from direct measurements on satellite links operating to above 30 GHz have been reviewed. Particular emphasis has been placed on the effects of precipitation on the Earth/space path, including rain attenuation, and ice particle depolarization. Other factors are sky noise, antenna gain degradation, scintillations, and bandwidth coherence. Each of the various <span class="hlt">propagation</span> factors has an effect on design criteria for communications systems. These criteria include link reliability, power margins, noise contribution, modulation and polarization factors, channel cross talk, error rate, and bandwidth limitations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950007512','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950007512"><span>Modes in light <span class="hlt">wave</span> <span class="hlt">propagating</span> in semiconductor laser</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Manko, Margarita A.</p> <p>1994-01-01</p> <p>The study of semiconductor laser based on an analogy of the Schrodinger equation and an equation describing light <span class="hlt">wave</span> <span class="hlt">propagation</span> in nonhomogeneous medium is developed. The active region of semiconductor laser is considered as optical waveguide confining the electromagnetic field in the cross-section (x,y) and allowing waveguide <span class="hlt">propagation</span> along the laser resonator (z). The mode structure is investigated taking into account the transversal and what is the important part of the suggested consideration longitudinal nonhomogeneity of the optical waveguide. It is shown that the Gaussian modes in the case correspond to spatial squeezing and correlation. Spatially squeezed two-mode structure of nonhomogeneous optical waveguide is given explicitly. Distribution of light among the laser discrete modes is presented. Properties of the spatially squeezed two-mode field are described. The analog of Franck-Condon principle for finding the maxima of the distribution function and the analog of Ramsauer effect for control of spatial distribution of laser emission are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70073331','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70073331"><span>Local <span class="hlt">tsunamis</span> and earthquake source parameters</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, Eric L.; Dmowska, Renata; Saltzman, Barry</p> <p>1999-01-01</p> <p>This chapter establishes the relationship among earthquake source parameters and the generation, <span class="hlt">propagation</span>, and run-up of local <span class="hlt">tsunamis</span>. In general terms, displacement of the seafloor during the earthquake rupture is modeled using the elastic dislocation theory for which the displacement field is dependent on the slip distribution, fault geometry, and the elastic response and properties of the medium. Specifically, nonlinear long-<span class="hlt">wave</span> theory governs the <span class="hlt">propagation</span> and run-up of <span class="hlt">tsunamis</span>. A parametric study is devised to examine the relative importance of individual earthquake source parameters on local <span class="hlt">tsunamis</span>, because the physics that describes <span class="hlt">tsunamis</span> from generation through run-up is complex. Analysis of the source parameters of various tsunamigenic earthquakes have indicated that the details of the earthquake source, namely, nonuniform distribution of slip along the fault plane, have a significant effect on the local <span class="hlt">tsunami</span> run-up. Numerical methods have been developed to address the realistic bathymetric and shoreline conditions. The accuracy of determining the run-up on shore is directly dependent on the source parameters of the earthquake, which provide the initial conditions used for the hydrodynamic models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhFl...29l4103B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhFl...29l4103B"><span>Impulse response and spatio-temporal <span class="hlt">wave</span>-packets: The common feature of rogue <span class="hlt">waves</span>, <span class="hlt">tsunami</span>, and transition to turbulence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bhaumik, Swagata; Sengupta, Tapan K.</p> <p>2017-12-01</p> <p>Here, we present the impulse response of the canonical zero pressure gradient boundary layer from the dynamical system approach. The fundamental physical mechanism of the impulse response is in creation of a spatio-temporal <span class="hlt">wave</span>-front (STWF) by a localized, time-impulsive wall excitation of the boundary layer. The present research is undertaken to explain the unit process of diverse phenomena in geophysical fluid flows and basic hydrodynamics. Creation of a <span class="hlt">tsunami</span> has been attributed to localized events in the ocean-bed caused by earthquakes, landslides, or volcanic eruptions, whose manifestation is in the run up to the coast by surface <span class="hlt">waves</span> of massive amplitude but of very finite fetch. Similarly rogue <span class="hlt">waves</span> have often been noted; a coherent account of the same is yet to appear, although some explanations have been proposed. Our studies in both two- and three-dimensional frameworks in Sengupta and Bhaumik ["Onset of turbulence from the receptivity stage of fluid flows," Phys. Rev. Lett. 107(15), 154501 (2011)] and Bhaumik and Sengupta ["Precursor of transition to turbulence: Spatiotemporal <span class="hlt">wave</span> front," Phys. Rev. E 89(4), 043018 (2014)] have shown that the STWF provides the central role for causing transition to turbulence by reproducing carefully conducted transition experiments. Here, we furthermore relax the condition of time behavior and use a Dirac-delta wall excitation for the impulse response. The present approach is not based on any simplification of the governing Navier-Stokes equation (NSE), which is unlike solving a nonlinear shallow water equation and/or nonlinear Schrödinger equation. The full nonlinear Navier-Stokes equation (NSE) is solved here using high accuracy dispersion relation preserving numerical schemes and using appropriate formulation of the NSE which minimizes error. The adopted numerical methods and formulation have been extensively validated with respect to various external and internal 2D and 3D flow problems. We also present</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28339227','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28339227"><span>Cosmic <span class="hlt">Tsunamis</span> in Modified Gravity: Disruption of Screening Mechanisms from Scalar <span class="hlt">Waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hagala, R; Llinares, C; Mota, D F</p> <p>2017-03-10</p> <p>Extending general relativity by adding extra degrees of freedom is a popular approach for explaining the accelerated expansion of the Universe and to build high energy completions of the theory of gravity. The presence of such new degrees of freedom is, however, tightly constrained from several observations and experiments that aim to test general relativity in a wide range of scales. The viability of a given modified theory of gravity, therefore, strongly depends on the existence of a screening mechanism that suppresses the extra degrees of freedom. We perform simulations, and find that <span class="hlt">waves</span> <span class="hlt">propagating</span> in the new degrees of freedom can significantly impact the efficiency of some screening mechanisms, thereby threatening the viability of these modified gravity theories. Specifically, we show that the <span class="hlt">waves</span> produced in the symmetron model can increase the amplitude of the fifth force and the parametrized post Newtonian parameters by several orders of magnitude.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvL.118j1301H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvL.118j1301H"><span>Cosmic <span class="hlt">Tsunamis</span> in Modified Gravity: Disruption of Screening Mechanisms from Scalar <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hagala, R.; Llinares, C.; Mota, D. F.</p> <p>2017-03-01</p> <p>Extending general relativity by adding extra degrees of freedom is a popular approach for explaining the accelerated expansion of the Universe and to build high energy completions of the theory of gravity. The presence of such new degrees of freedom is, however, tightly constrained from several observations and experiments that aim to test general relativity in a wide range of scales. The viability of a given modified theory of gravity, therefore, strongly depends on the existence of a screening mechanism that suppresses the extra degrees of freedom. We perform simulations, and find that <span class="hlt">waves</span> <span class="hlt">propagating</span> in the new degrees of freedom can significantly impact the efficiency of some screening mechanisms, thereby threatening the viability of these modified gravity theories. Specifically, we show that the <span class="hlt">waves</span> produced in the symmetron model can increase the amplitude of the fifth force and the parametrized post Newtonian parameters by several orders of magnitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JTePh..61.1765V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JTePh..61.1765V"><span>Modeling the <span class="hlt">propagation</span> of electromagnetic <span class="hlt">waves</span> over the surface of the human body</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vendik, I. B.; Vendik, O. G.; Kirillov, V. V.; Pleskachev, V. V.; Tural'chuk, P. A.</p> <p>2016-12-01</p> <p>The results of modeling and an experimental study of electromagnetic (EM) <span class="hlt">waves</span> in microwave range <span class="hlt">propagating</span> along the surface of the human body have been presented. The parameters of <span class="hlt">wave</span> <span class="hlt">propagation</span>, such as the attenuation and phase velocity, have also been investigated. The calculation of the <span class="hlt">propagation</span> of EM <span class="hlt">waves</span> by the numerical method FDTD (finite difference time domain), as well as the use of the analytical model of the <span class="hlt">propagation</span> of the EM <span class="hlt">wave</span> along flat and curved surfaces has been fulfilled. An experimental study on a human body has been conducted. It has been shown that creeping <span class="hlt">waves</span> are slow and exhibit a noticeable dispersion, while the surface <span class="hlt">waves</span> are dispersionless and <span class="hlt">propagate</span> at the speed of light in free space. A comparison of the results of numerical simulation, analytical calculation, and experimental investigations at a frequency of 2.55 GHz has been carried out.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JOC....33...57J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JOC....33...57J"><span>Re-evaluation of ``;The <span class="hlt">Propagation</span> of Radiation in the Spherical <span class="hlt">Wave</span> Form''</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Joshi, Narahari V.</p> <p>2012-03-01</p> <p>It is well accepted that radiation <span class="hlt">propagates</span> in the free space (without obstacles) in a spherical <span class="hlt">wave</span> form as well as in a plane <span class="hlt">wave</span> form. Almost all observed phenomena such as interference, diffraction etc are explained satisfactorily on the basis of spherical <span class="hlt">wave</span> <span class="hlt">propagation</span> with a slight alteration in the mathematical treatment. However, one of the fundamental aspects, namely the intensity of the radiation as a function of the distance still remains an unsolved problem as the intensity varies with <italic>1/</italic>(distance)<italic>2</italic> when one represents the <span class="hlt">propagation</span> in terms of spherical <span class="hlt">waves</span> while it is independent of the distance if it is considered as a plane <span class="hlt">wave</span>. In order to understand this puzzle, the <span class="hlt">propagation</span> by a spherical <span class="hlt">wave</span> form is reexamined. It is found that conversion of fields into particle (vice versa), via the field quantization process, explains several dilemma related with the radiation <span class="hlt">propagation</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014NJPh...16c3012G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014NJPh...16c3012G"><span>Stationary <span class="hlt">propagation</span> of a <span class="hlt">wave</span> segment along an inhomogeneous excitable stripe</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gao, Xiang; Zhang, Hong; Zykov, Vladimir; Bodenschatz, Eberhard</p> <p>2014-03-01</p> <p>We report a numerical and theoretical study of an excitation <span class="hlt">wave</span> <span class="hlt">propagating</span> along an inhomogeneous stripe of an excitable medium. The stripe inhomogeneity is due to a jump of the <span class="hlt">propagation</span> velocity in the direction transverse to the <span class="hlt">wave</span> motion. Stationary <span class="hlt">propagating</span> <span class="hlt">wave</span> segments of rather complicated curved shapes are observed. We demonstrate that the stationary segment shape strongly depends on the initial conditions which are used to initiate the excitation <span class="hlt">wave</span>. In a certain parameter range, the <span class="hlt">wave</span> <span class="hlt">propagation</span> is blocked at the inhomogeneity boundary, although the <span class="hlt">wave</span> <span class="hlt">propagation</span> is supported everywhere within the stripe. A free-boundary approach is applied to describe these phenomena which are important for a wide variety of applications from cardiology to information processing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMMR41C0419A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMMR41C0419A"><span>Shock <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Layered Planetary Interiors: Revisited</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arkani-Hamed, J.; Monteux, J.</p> <p>2017-12-01</p> <p>The end of the terrestrial planet accretion is characterized by numerous large impacts. About 90% of the mass of a large planet is accreted while the core mantle separation is occurring, because of the accretionary and the short-lived radio-isotope heating. The characteristics of the shockwave <span class="hlt">propagation</span>, hence the existing scaling laws are poorly known within the layered planets. Here, we use iSALE-2D hydrocode simulations to calculate shock pressure in a differentiated Mars type body for impact velocities of 5-20 km/s, and impactor sizes of 100-400 km. We use two different rheologies for the target interior, an inviscid model ("no-stress model") and a pressure and damage-dependent strength model ("elaborated model"). To better characterize the shock pressure within the whole mantle as a function of distance from the impact site, we propose the following distribution: (1) a near field zone larger than the isobaric core that extends to 7-15 times the projectile radius into the target, where the peak shock pressure decays exponentially with increasing distance, (2) a far field zone where the pressure decays with distance following a power law. The shock pressure decreases more rapidly with distance in the near field for the elaborated model than for the no-stress model because of the influence of acoustic fluidization and damage. However to better illustrate the influence of the rheology on the shock <span class="hlt">propagation</span>, we use the same expressions to fit the shock pressure with distance for both models. At the core-mantle boundary, CMB, the peak shock pressure jumps as the shock <span class="hlt">wave</span> enters the core. We derived the boundary condition at CMB for the peak shock pressure. It is less sensitive to the impact velocity or the impactor size, but strongly depends on the rheology of the planet's mantle. Because of the lower shock <span class="hlt">wave</span> velocity in the core compared to that in the mantle, the refracted shockwave <span class="hlt">propagates</span> toward the symmetry axis of the planet, and the shock</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017CompM..60..725B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017CompM..60..725B"><span><span class="hlt">Wave</span> dispersion and <span class="hlt">propagation</span> in state-based peridynamics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Butt, Sahir N.; Timothy, Jithender J.; Meschke, Günther</p> <p>2017-11-01</p> <p>Peridynamics is a nonlocal continuum model which offers benefits over classical continuum models in cases, where discontinuities, such as cracks, are present in the deformation field. However, the nonlocal characteristics of peridynamics leads to a dispersive dynamic response of the medium. In this study we focus on the dispersion properties of a state-based linear peridynamic solid model and specifically investigate the role of the peridynamic horizon. We derive the dispersion relation for one, two and three dimensional cases and investigate the effect of horizon size, mesh size (lattice spacing) and the influence function on the dispersion properties. We show how the influence function can be used to minimize <span class="hlt">wave</span> dispersion at a fixed lattice spacing and demonstrate it qualitatively by <span class="hlt">wave</span> <span class="hlt">propagation</span> analysis in one- and two-dimensional models of elastic solids. As a main contribution of this paper, we propose to associate peridynamic non-locality expressed by the horizon with a characteristic length scale related to the material microstructure. To this end, the dispersion curves obtained from peridynamics are compared with experimental data for two kinds of sandstone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28860632','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28860632"><span>Modelling viscoacoustic <span class="hlt">wave</span> <span class="hlt">propagation</span> with the lattice Boltzmann method.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Xia, Muming; Wang, Shucheng; Zhou, Hui; Shan, Xiaowen; Chen, Hanming; Li, Qingqing; Zhang, Qingchen</p> <p>2017-08-31</p> <p>In this paper, the lattice Boltzmann method (LBM) is employed to simulate <span class="hlt">wave</span> <span class="hlt">propagation</span> in viscous media. LBM is a kind of microscopic method for modelling <span class="hlt">waves</span> through tracking the evolution states of a large number of discrete particles. By choosing different relaxation times in LBM experiments and using spectrum ratio method, we can reveal the relationship between the quality factor Q and the parameter τ in LBM. A two-dimensional (2D) homogeneous model and a two-layered model are tested in the numerical experiments, and the LBM results are compared against the reference solution of the viscoacoustic equations based on the Kelvin-Voigt model calculated by finite difference method (FDM). The wavefields and amplitude spectra obtained by LBM coincide with those by FDM, which demonstrates the capability of the LBM with one relaxation time. The new scheme is relatively simple and efficient to implement compared with the traditional lattice methods. In addition, through a mass of experiments, we find that the relaxation time of LBM has a quantitative relationship with Q. Such a novel scheme offers an alternative forward modelling kernel for seismic inversion and a new model to describe the underground media.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1406643-wave-propagation-equivalent-continuums-representing-truss-lattice-materials','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1406643-wave-propagation-equivalent-continuums-representing-truss-lattice-materials"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in equivalent continuums representing truss lattice materials</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Messner, Mark C.; Barham, Matthew I.; Kumar, Mukul; ...</p> <p>2015-07-29</p> <p>Stiffness scales linearly with density in stretch-dominated lattice meta-materials offering the possibility of very light yet very stiff structures. Current additive manufacturing techniques can assemble structures from lattice materials, but the design of such structures will require accurate, efficient simulation methods. Equivalent continuum models have several advantages over discrete truss models of stretch dominated lattices, including computational efficiency and ease of model construction. However, the development an equivalent model suitable for representing the dynamic response of a periodic truss in the small deformation regime is complicated by microinertial effects. This study derives a dynamic equivalent continuum model for periodic trussmore » structures suitable for representing long-wavelength <span class="hlt">wave</span> <span class="hlt">propagation</span> and verifies it against the full Bloch <span class="hlt">wave</span> theory and detailed finite element simulations. The model must incorporate microinertial effects to accurately reproduce long wavelength characteristics of the response such as anisotropic elastic soundspeeds. Finally, the formulation presented here also improves upon previous work by preserving equilibrium at truss joints for simple lattices and by improving numerical stability by eliminating vertices in the effective yield surface.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUSMOS41A..04K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUSMOS41A..04K"><span>Simulation the Effect of Internal <span class="hlt">Wave</span> on the Acoustic <span class="hlt">Propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ko, D. S.</p> <p>2005-05-01</p> <p>An acoustic radiation transport model with the Monte Carlo solution has been developed and applied to study the effect of internal <span class="hlt">wave</span> induced random oceanic fluctuations on the deep ocean acoustic <span class="hlt">propagation</span>. Refraction in the ocean sound channel is performed by means of bi-cubic spline interpolation of discrete deterministic ray paths in the angle(energy)-range-depth coordinates. Scattering by random internal <span class="hlt">wave</span> fluctuations is accomplished by sampling a power law scattering kernel applying the rejection method. Results from numerical experiments show that the mean positions of acoustic rays are significantly displaced tending toward the sound channel axis due to the asymmetry of the scattering kernel. The spreading of ray depths and angles about the means depends strongly on frequency. The envelope of the ray displacement spreading is found to be proportional to the square root of range which is different from "3/2 law" found in the non-channel case. Suppression of the spreading is due to the anisotropy of fluctuations and especially due to the presence of sound channel itself.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhyD..365...27V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhyD..365...27V"><span><span class="hlt">Wave</span> <span class="hlt">propagation</span> in a strongly nonlinear locally resonant granular crystal</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vorotnikov, K.; Starosvetsky, Y.; Theocharis, G.; Kevrekidis, P. G.</p> <p>2018-02-01</p> <p>In this work, we study the <span class="hlt">wave</span> <span class="hlt">propagation</span> in a recently proposed acoustic structure, the locally resonant granular crystal. This structure is composed of a one-dimensional granular crystal of hollow spherical particles in contact, containing linear resonators. The relevant model is presented and examined through a combination of analytical approximations (based on ODE and nonlinear map analysis) and of numerical results. The generic dynamics of the system involves a degradation of the well-known traveling pulse of the standard Hertzian chain of elastic beads. Nevertheless, the present system is richer, in that as the primary pulse decays, secondary ones emerge and eventually interfere with it creating modulated wavetrains. Remarkably, upon suitable choices of parameters, this interference "distills" a weakly nonlocal solitary <span class="hlt">wave</span> (a "nanopteron"). This motivates the consideration of such nonlinear structures through a separate Fourier space technique, whose results suggest the existence of such entities not only with a single-side tail, but also with periodic tails on both ends. These tails are found to oscillate with the intrinsic oscillation frequency of the out-of-phase motion between the outer hollow bead and its internal linear attachment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1988JSV...126..183V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1988JSV...126..183V"><span>Application of ply level analysis to flexural <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Valisetty, R. R.; Rehfield, L. W.</p> <p>1988-10-01</p> <p>A brief survey is presented of the shear deformation theories of laminated plates. It indicates that there are certain non-classical influences that affect bending-related behavior in the same way as do the transverse shear stresses. They include bending- and stretching-related section warping and the concomitant non-classical surface parallel stress contributions and the transverse normal stress. A bending theory gives significantly improved performance if these non-classical affects are incorporated. The heterogeneous shear deformations that are characteristic of laminates with highly dissimilar materials, however, require that attention be paid to the modeling of local rotations. In this paper, it is shown that a ply level analysis can be used to model such disparate shear deformations. Here, equilibrium of each layer is analyzed separately. Earlier applications of this analysis include free-edge laminate stresses. It is now extended to the study of flexural <span class="hlt">wave</span> <span class="hlt">propagation</span> in laminates. A recently developed homogeneous plate theory is used as a ply level model. Due consideration is given to the non-classical influences and no shear correction factors are introduced extraneously in this theory. The results for the lowest flexural mode of travelling planar harmonic <span class="hlt">waves</span> indicate that this approach is competitive and yields better results for certain laminates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AIPC.1113..185P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AIPC.1113..185P"><span>Numerical Simulation of Shock <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Fractured Cortical Bone</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Padilla, Frédéric; Cleveland, Robin</p> <p>2009-04-01</p> <p>Shock <span class="hlt">waves</span> (SW) are considered a promising method to treat bone non unions, but the associated mechanisms of action are not well understood. In this study, numerical simulations are used to quantify the stresses induced by SWs in cortical bone tissue. We use a 3D FDTD code to solve the linear lossless equations that describe <span class="hlt">wave</span> <span class="hlt">propagation</span> in solids and fluids. A 3D model of a fractured rat femur was obtained from micro-CT data with a resolution of 32 μm. The bone was subject to a plane SW pulse with a peak positive pressure of 40 MPa and peak negative pressure of -8 MPa. During the simulations the principal tensile stress and maximum shear stress were tracked throughout the bone. It was found that the simulated stresses in a transverse plane relative to the bone axis may reach values higher than the tensile and shear strength of the bone tissue (around 50 MPa). These results suggest that the stresses induced by the SW may be large enough to initiate local micro-fractures, which may in turn trigger the start of bone healing for the case of a non union.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16214154','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16214154"><span>Modeling of weak blast <span class="hlt">wave</span> <span class="hlt">propagation</span> in the lung.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>D'yachenko, A I; Manyuhina, O V</p> <p>2006-01-01</p> <p>Blast injuries of the lung are the most life-threatening after an explosion. The choice of physical parameters responsible for trauma is important to understand its mechanism. We developed a one-dimensional linear model of an elastic <span class="hlt">wave</span> <span class="hlt">propagation</span> in foam-like pulmonary parenchyma to identify the possible cause of edema due to the impact load. The model demonstrates different injury localizations for free and rigid boundary conditions. The following parameters were considered: strain, velocity, pressure in the medium and stresses in structural elements, energy dissipation, parameter of viscous criterion. Maximum underpressure is the most suitable <span class="hlt">wave</span> parameter to be the criterion for edema formation in a rabbit lung. We supposed that observed scattering of experimental data on edema severity is induced by the physiological variety of rabbit lungs. The criterion and the model explain this scattering. The model outlines the demands for experimental data to make an unambiguous choice of physical parameters responsible for lung trauma due to impact load.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003PApGe.160..509W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003PApGe.160..509W"><span><span class="hlt">Wave</span> <span class="hlt">Propagation</span>, Scattering and Imaging Using Dual-domain One-way and One-return <span class="hlt">Propagators</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, R.-S.</p> <p></p> <p>- Dual-domain one-way <span class="hlt">propagators</span> implement <span class="hlt">wave</span> <span class="hlt">propagation</span> in heterogeneous media in mixed domains (space-wavenumber domains). One-way <span class="hlt">propagators</span> neglect <span class="hlt">wave</span> reverberations between heterogeneities but correctly handle the forward multiple-scattering including focusing/defocusing, diffraction, refraction and interference of <span class="hlt">waves</span>. The algorithm shuttles between space-domain and wavenumber-domain using FFT, and the operations in the two domains are self-adaptive to the complexity of the media. The method makes the best use of the operations in each domain, resulting in efficient and accurate <span class="hlt">propagators</span>. Due to recent progress, new versions of dual-domain methods overcame some limitations of the classical dual-domain methods (phase-screen or split-step Fourier methods) and can <span class="hlt">propagate</span> large-angle <span class="hlt">waves</span> quite accurately in media with strong velocity contrasts. These methods can deliver superior image quality (high resolution/high fidelity) for complex subsurface structures. One-way and one-return (De Wolf approximation) <span class="hlt">propagators</span> can be also applied to <span class="hlt">wave</span>-field modeling and simulations for some geophysical problems. In the article, a historical review and theoretical analysis of the Born, Rytov, and De Wolf approximations are given. A review on classical phase-screen or split-step Fourier methods is also given, followed by a summary and analysis of the new dual-domain <span class="hlt">propagators</span>. The applications of the new <span class="hlt">propagators</span> to seismic imaging and modeling are reviewed with several examples. For seismic imaging, the advantages and limitations of the traditional Kirchhoff migration and time-space domain finite-difference migration, when applied to 3-D complicated structures, are first analyzed. Then the special features, and applications of the new dual-domain methods are presented. Three versions of GSP (generalized screen <span class="hlt">propagators</span>), the hybrid pseudo-screen, the wide-angle Padé-screen, and the higher-order generalized screen <span class="hlt">propagators</span> are discussed. Recent</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4887769','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4887769"><span>Physical modelling of <span class="hlt">tsunamis</span> generated by three-dimensional deformable granular landslides on planar and conical island slopes</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2016-01-01</p> <p><span class="hlt">Tsunamis</span> generated by landslides and volcanic island collapses account for some of the most catastrophic events recorded, yet critically important field data related to the landslide motion and <span class="hlt">tsunami</span> evolution remain lacking. Landslide-generated <span class="hlt">tsunami</span> source and <span class="hlt">propagation</span> scenarios are physically modelled in a three-dimensional <span class="hlt">tsunami</span> <span class="hlt">wave</span> basin. A unique pneumatic landslide <span class="hlt">tsunami</span> generator was deployed to simulate landslides with varying geometry and kinematics. The landslides were generated on a planar hill slope and divergent convex conical hill slope to study lateral hill slope effects on the <span class="hlt">wave</span> characteristics. The leading <span class="hlt">wave</span> crest amplitude generated on a planar hill slope is larger on average than the leading <span class="hlt">wave</span> crest generated on a convex conical hill slope, whereas the leading <span class="hlt">wave</span> trough and second <span class="hlt">wave</span> crest amplitudes are smaller. Between 1% and 24% of the landslide kinetic energy is transferred into the <span class="hlt">wave</span> train. Cobble landslides transfer on average 43% more kinetic energy into the <span class="hlt">wave</span> train than corresponding gravel landslides. Predictive equations for the offshore <span class="hlt">propagating</span> <span class="hlt">wave</span> amplitudes, periods, celerities and lengths generated by landslides on planar and divergent convex conical hill slopes are derived, which allow an initial rapid <span class="hlt">tsunami</span> hazard assessment. PMID:27274697</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27274697','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27274697"><span>Physical modelling of <span class="hlt">tsunamis</span> generated by three-dimensional deformable granular landslides on planar and conical island slopes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>McFall, Brian C; Fritz, Hermann M</p> <p>2016-04-01</p> <p><span class="hlt">Tsunamis</span> generated by landslides and volcanic island collapses account for some of the most catastrophic events recorded, yet critically important field data related to the landslide motion and <span class="hlt">tsunami</span> evolution remain lacking. Landslide-generated <span class="hlt">tsunami</span> source and <span class="hlt">propagation</span> scenarios are physically modelled in a three-dimensional <span class="hlt">tsunami</span> <span class="hlt">wave</span> basin. A unique pneumatic landslide <span class="hlt">tsunami</span> generator was deployed to simulate landslides with varying geometry and kinematics. The landslides were generated on a planar hill slope and divergent convex conical hill slope to study lateral hill slope effects on the <span class="hlt">wave</span> characteristics. The leading <span class="hlt">wave</span> crest amplitude generated on a planar hill slope is larger on average than the leading <span class="hlt">wave</span> crest generated on a convex conical hill slope, whereas the leading <span class="hlt">wave</span> trough and second <span class="hlt">wave</span> crest amplitudes are smaller. Between 1% and 24% of the landslide kinetic energy is transferred into the <span class="hlt">wave</span> train. Cobble landslides transfer on average 43% more kinetic energy into the <span class="hlt">wave</span> train than corresponding gravel landslides. Predictive equations for the offshore <span class="hlt">propagating</span> <span class="hlt">wave</span> amplitudes, periods, celerities and lengths generated by landslides on planar and divergent convex conical hill slopes are derived, which allow an initial rapid <span class="hlt">tsunami</span> hazard assessment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.U41B0028A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.U41B0028A"><span>Poroelastic Seismic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> Modeling of CO2 Sequestration Effects</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aldridge, D. F.; Bartel, L. C.</p> <p>2009-12-01</p> <p>Long term geologic sequestration of carbon dioxide (CO2) is considered a viable approach for removing large amounts of excess carbon from the earth’s surface environment. As CO2 is injected into a subsurface porous formation, it displaces (or mixes with) in situ pore fluids. Seismic reflection and transmission responses of the formation depend on the degree of CO2 substitution. Additionally, geochemical reactions involving CO2 and mineral grains alter the bulk and shear moduli of the solid constituent and/or the matrix of the porous medium. We examine full waveform, wide-angle, amplitude vs. offset (AVO) responses of sandstone and carbonate layers. Synthetic seismic data are calculated with a 3D poroelastic <span class="hlt">wave</span> <span class="hlt">propagation</span> algorithm that solves Biot’s system of thirteen coupled partial differential equations via an explicit, time-domain, finite-difference method. All common seismological phases (primary and multiple reflections, mode conversions, head <span class="hlt">waves</span>, surface and interface <span class="hlt">waves</span>) are generated with fidelity, provided spatial and temporal gridding intervals are sufficiently fine. Initial calculations indicate that full or partial replacement of H2O by CO2 is readily detected by the AVO recording configuration, particularly with long offset events. Difference seismogram amplitudes of surface-recorded particle velocities range up to ~25%. Equivalent elastic medium responses, with elastic parameters assigned by Gassmann formulae, are inadequate at higher frequencies. Finally, these sensitivity modeling experiments are being extended to vertical seismic profiling geometries. Sandia National Laboratories is a multiprogram science and engineering facility operated by Sandia Corporation, a Lockheed-Martin company, for the US Department of Energy’s National Nuclear Security Administration, under contract DE-AC04-94AL85000.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PApGe.175.1371S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PApGe.175.1371S"><span>Ray Tracing for Dispersive <span class="hlt">Tsunamis</span> and Source Amplitude Estimation Based on Green's Law: Application to the 2015 Volcanic <span class="hlt">Tsunami</span> Earthquake Near Torishima, South of Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sandanbata, Osamu; Watada, Shingo; Satake, Kenji; Fukao, Yoshio; Sugioka, Hiroko; Ito, Aki; Shiobara, Hajime</p> <p>2018-04-01</p> <p>Ray tracing, which has been widely used for seismic <span class="hlt">waves</span>, was also applied to <span class="hlt">tsunamis</span> to examine the bathymetry effects during <span class="hlt">propagation</span>, but it was limited to linear shallow-water <span class="hlt">waves</span>. Green's law, which is based on the conservation of energy flux, has been used to estimate <span class="hlt">tsunami</span> amplitude on ray paths. In this study, we first propose a new ray tracing method extended to dispersive <span class="hlt">tsunamis</span>. By using an iterative algorithm to map two-dimensional <span class="hlt">tsunami</span> velocity fields at different frequencies, ray paths at each frequency can be traced. We then show that Green's law is valid only outside the source region and that extension of Green's law is needed for source amplitude estimation. As an application example, we analyzed <span class="hlt">tsunami</span> <span class="hlt">waves</span> generated by an earthquake that occurred at a submarine volcano, Smith Caldera, near Torishima, Japan, in 2015. The ray-tracing results reveal that the ray paths are very dependent on its frequency, particularly at deep oceans. The validity of our frequency-dependent ray tracing is confirmed by the comparison of arrival angles and travel times with those of observed <span class="hlt">tsunami</span> waveforms at an array of ocean bottom pressure gauges. The <span class="hlt">tsunami</span> amplitude at the source is nearly twice or more of that just outside the source estimated from the array <span class="hlt">tsunami</span> data by Green's law.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoRL..45.2064D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoRL..45.2064D"><span>Rossby <span class="hlt">Wave</span> <span class="hlt">Propagation</span> into the Northern Hemisphere Stratosphere: The Role of Zonal Phase Speed</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Domeisen, Daniela I. V.; Martius, Olivia; Jiménez-Esteve, Bernat</p> <p>2018-02-01</p> <p>Sudden stratospheric warming (SSW) events are to a dominant part induced by upward <span class="hlt">propagating</span> planetary <span class="hlt">waves</span>. While theory predicts that the zonal phase speed of a tropospheric <span class="hlt">wave</span> forcing affects <span class="hlt">wave</span> <span class="hlt">propagation</span> into the stratosphere, its relevance for SSW events has so far not been considered. This study shows in a linear <span class="hlt">wave</span> diagnostic and in reanalysis data that phase speeds tend eastward as <span class="hlt">waves</span> <span class="hlt">propagate</span> upward, indicating that the stratosphere preselects eastward phase speeds for <span class="hlt">propagation</span>, especially for zonal <span class="hlt">wave</span> number 2. This also affects SSW events: Split SSW events tend to be preceded by anomalously eastward zonal phase speeds. Zonal phase speed may indeed explain part of the increased <span class="hlt">wave</span> flux observed during the preconditioning of SSW events, as, for example, for the record 2009 SSW event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JMMM..450....7L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JMMM..450....7L"><span>Homogeneous microwave field emitted <span class="hlt">propagating</span> spin <span class="hlt">waves</span>: Direct imaging and modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lohman, Mathis; Mozooni, Babak; McCord, Jeffrey</p> <p>2018-03-01</p> <p>We explore the generation of <span class="hlt">propagating</span> dipolar spin <span class="hlt">waves</span> by homogeneous magnetic field excitation in the proximity of the boundaries of magnetic microstructures. Domain wall motion, precessional dynamics, and <span class="hlt">propagating</span> spin <span class="hlt">waves</span> are directly imaged by time-resolved wide-field magneto-optical Kerr effect microscopy. The aspects of spin <span class="hlt">wave</span> generation are clarified by micromagnetic calculations matching the experimental results. The region of dipolar spin <span class="hlt">wave</span> formation is confined to the local resonant excitation due to non-uniform internal demagnetization fields at the edges of the patterned sample. Magnetic domain walls act as a border for the <span class="hlt">propagation</span> of plane and low damped spin <span class="hlt">waves</span>, thus restraining the spin <span class="hlt">waves</span> within the individual magnetic domains. The findings are of significance for the general understanding of structural and configurational magnetic boundaries for the creation, the <span class="hlt">propagation</span>, and elimination of spin <span class="hlt">waves</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.U22A..02B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.U22A..02B"><span>Development of a GNSS-Enhanced <span class="hlt">Tsunami</span> Early Warning System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bawden, G. W.; Melbourne, T. I.; Bock, Y.; Song, Y. T.; Komjathy, A.</p> <p>2015-12-01</p> <p>The past decade has witnessed a terrible loss of life and economic disruption caused by large earthquakes and resultant <span class="hlt">tsunamis</span> impacting coastal communities and infrastructure across the Indo-Pacific region. NASA has funded the early development of a prototype real-time Global Navigation Satellite System (RT-GNSS) based rapid earthquake and <span class="hlt">tsunami</span> early warning (GNSS-TEW) system that may be used to enhance seismic <span class="hlt">tsunami</span> early warning systems for large earthquakes. This prototype GNSS-TEW system geodetically estimates fault parameters (earthquake magnitude, location, strike, dip, and slip magnitude/direction on a gridded fault plane both along strike and at depth) and <span class="hlt">tsunami</span> source parameters (seafloor displacement, <span class="hlt">tsunami</span> energy scale, and 3D <span class="hlt">tsunami</span> initials) within minutes after the mainshock based on dynamic numerical inversions/regressions of the real-time measured displacements within a spatially distributed real-time GNSS network(s) spanning the epicentral region. It is also possible to measure fluctuations in the ionosphere's total electron content (TEC) in the RT-GNSS data caused by the pressure <span class="hlt">wave</span> from the <span class="hlt">tsunami</span>. This TEC approach can detect if a <span class="hlt">tsunami</span> has been triggered by an earthquake, track its <span class="hlt">waves</span> as they <span class="hlt">propagate</span> through the oceanic basins, and provide upwards of 45 minutes early warning. These combined real-time geodetic approaches will very quickly address a number of important questions in the immediate minutes following a major earthquake: How big was the earthquake and what are its fault parameters? Could the earthquake have produced a <span class="hlt">tsunami</span> and was a <span class="hlt">tsunami</span> generated?</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22394437','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22394437"><span>Ocean <span class="hlt">waves</span> and roadside spirits: Thai health service providers' post-<span class="hlt">tsunami</span> psychosocial health.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Varley, Emma; Isaranuwatchai, Wanrudee; Coyte, Peter C</p> <p>2012-10-01</p> <p>A massive earthquake off the west coast of Sumatra in Indonesia triggered a <span class="hlt">tsunami</span> on 26 December 2004. At least five million people around the world were affected, and the total number of deaths exceeded 280,000. In Thailand, the <span class="hlt">tsunami</span> struck six southern provinces, where the disaster's immediate impact was catastrophic. Based on ethnographic fieldwork in Phang Nga Province (2007), this paper provides an overview of the disaster's psychosocial consequences for Thai health service providers, the vast majority of whom were bypassed by regional post-<span class="hlt">tsunami</span> mental health initiatives. The available <span class="hlt">tsunami</span> literature only briefly attends to health providers' experience of professional 'burn-out', rather than explores the <span class="hlt">tsunami</span>'s wide spectrum of psychosocial effects. This research aims to remedy such oversights through 'critical medical' and 'interpretive phenomenological' analysis of the diverse and culturally-situated ways in which health providers' experienced the <span class="hlt">tsunami</span>. The paper concludes by arguing for disaster-related psychosocial interventions to involve health providers explicitly. © 2012 The Author(s). Journal compilation © Overseas Development Institute, 2012.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMNH32A..04K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMNH32A..04K"><span><span class="hlt">Tsunami</span> Forecasting in the Atlantic Basin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Knight, W. R.; Whitmore, P.; Sterling, K.; Hale, D. A.; Bahng, B.</p> <p>2012-12-01</p> <p>The mission of the West Coast and Alaska <span class="hlt">Tsunami</span> Warning Center (WCATWC) is to provide advance <span class="hlt">tsunami</span> warning and guidance to coastal communities within its Area-of-Responsibility (AOR). Predictive <span class="hlt">tsunami</span> models, based on the shallow water <span class="hlt">wave</span> equations, are an important part of the Center's guidance support. An Atlantic-based counterpart to the long-standing forecasting ability in the Pacific known as the Alaska <span class="hlt">Tsunami</span> Forecast Model (ATFM) is now developed. The Atlantic forecasting method is based on ATFM version 2 which contains advanced capabilities over the original model; including better handling of the dynamic interactions between grids, inundation over dry land, new forecast model products, an optional non-hydrostatic approach, and the ability to pre-compute larger and more finely gridded regions using parallel computational techniques. The wide and nearly continuous Atlantic shelf region presents a challenge for forecast models. Our solution to this problem has been to develop a single unbroken high resolution sub-mesh (currently 30 arc-seconds), trimmed to the shelf break. This allows for edge <span class="hlt">wave</span> <span class="hlt">propagation</span> and for kilometer scale bathymetric feature resolution. Terminating the fine mesh at the 2000m isobath keeps the number of grid points manageable while allowing for a coarse (4 minute) mesh to adequately resolve deep water <span class="hlt">tsunami</span> dynamics. Higher resolution sub-meshes are then included around coastal forecast points of interest. The WCATWC Atlantic AOR includes eastern U.S. and Canada, the U.S. Gulf of Mexico, Puerto Rico, and the Virgin Islands. Puerto Rico and the Virgin Islands are in very close proximity to well-known <span class="hlt">tsunami</span> sources. Because travel times are under an hour and response must be immediate, our focus is on pre-computing many <span class="hlt">tsunami</span> source "scenarios" and compiling those results into a database accessible and calibrated with observations during an event. Seismic source evaluation determines the order of model pre</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhDT.......120D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhDT.......120D"><span>Ferroics and Multiferroics for Dynamically Controlled Terahertz <span class="hlt">Wave</span> <span class="hlt">Propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dutta, Moumita</p> <p></p> <p>The terahertz (THz) region of electromagnetic spectra, referred roughly to the frequency range of 100 GHz (0.1 THz) to 10 THz, is the bridging gap between the microwave and infrared spectral bands. Previously confined only to astronomy and analytical sciences due to the unavailability of technology, with the recent advancements in non-linear optics, this novel field has now started emerging as a promising area of research and study. Considerable efforts are underway to fill this 'THz gap' by developing efficient THz sources, detectors, switches, modulators etc. Be it any field, to realize this regime as one of the active frontiers, it is essential to have an efficient control over the <span class="hlt">wave</span> <span class="hlt">propagation</span>. In this research, functional materials (ferroics/multiferroics) have been explored to attain dynamic control over the THz beam <span class="hlt">propagation</span>. The objective is to expand the horizon by enabling different family of materials to be incorporated in the design of THz modulators, exploiting the novel properties they exhibit. To reach that goal, following a comprehensive but selective (to dielectrics) review on the current-status of this research field, some preliminary studies on ferroic materials have been performed to understand the crux of ferroism and the novel functionalities they have to offer. An analytical study on microstructural and nanoscale properties of solid-solution ferroelectric Pb(Zr0.52Ti 0.48)O3 (PZT) and composite bio-ferroic seashells have been performed to elucidate the significance of structure-property relationship in intrinsic ferroelectrics. Moving forward, engineered ferroelectricity has been demonstrated. A precise control over fabrication parameters has been exploited to introduce oxygen-vacancy defined nanoscale polar-domains in centrosymmetric BaZrO3. Realizing that structure-property relationship can significantly influence the material properties and therefore the device performance, models for figure of merit analysis have been developed for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD1046558','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD1046558"><span>Quantifying Electromagnetic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> Environment Using Measurements From A Small Buoy</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2017-06-01</p> <p>ELECTROMAGNETIC <span class="hlt">WAVE</span> <span class="hlt">PROPAGATION</span> ENVIRONMENT USING MEASUREMENTS FROM A SMALL BUOY by Andrew E. Sweeney June 2017 Thesis Advisor: Qing Wang...TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE QUANTIFYING ELECTROMAGNETIC <span class="hlt">WAVE</span> <span class="hlt">PROPAGATION</span> ENVIRONMENT USING MEASUREMENTS FROM A...the Coupled Air Sea Processes and Electromagnetic (EM) ducting Research (CASPER), to understand air-sea interaction processes and their representation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1352403','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1352403"><span>geometric optics and WKB method for electromagnetic <span class="hlt">wave</span> <span class="hlt">propagation</span> in an inhomogeneous plasma near cutoff</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Light, Max Eugene</p> <p></p> <p>This report outlines the theory underlying electromagnetic (EM) <span class="hlt">wave</span> <span class="hlt">propagation</span> in an unmagnetized, inhomogeneous plasma. The inhomogeneity is given by a spatially nonuniform plasma electron density n e(r), which will modify the <span class="hlt">wave</span> <span class="hlt">propagation</span> in the direction of the gradient rn e(r).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19780037977&hterms=averaged+lagrangian&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Daveraged%2Blagrangian','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19780037977&hterms=averaged+lagrangian&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Daveraged%2Blagrangian"><span>Microscopic Lagrangian description of warm plasmas. I - Linear <span class="hlt">wave</span> <span class="hlt">propagation</span>. II - Nonlinear <span class="hlt">wave</span> interactions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kim, H.; Crawford, F. W.</p> <p>1977-01-01</p> <p>It is pointed out that the conventional iterative analysis of nonlinear plasma <span class="hlt">wave</span> phenomena, which involves a direct use of Maxwell's equations and the equations describing the particle dynamics, leads to formidable theoretical and algebraic complexities, especially for warm plasmas. As an effective alternative, the Lagrangian method may be applied. It is shown how this method may be used in the microscopic description of small-signal <span class="hlt">wave</span> <span class="hlt">propagation</span> and in the study of nonlinear <span class="hlt">wave</span> interactions. The linear theory is developed for an infinite, homogeneous, collisionless, warm magnetoplasma. A summary is presented of a perturbation expansion scheme described by Galloway and Kim (1971), and Lagrangians to third order in perturbation are considered. Attention is given to the averaged-Lagrangian density, the action-transfer and coupled-mode equations, and the general solution of the coupled-mode equations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.6397K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.6397K"><span>2011 Great East Japan <span class="hlt">tsunami</span> in Okhotsk Sea region: numerical modelings and observation data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kostenko, Irina; Zaytsev, Andrey; Yalciner, Ahmet; Pelinovsky, Efim</p> <p>2013-04-01</p> <p>The 11 March, 2011 Great East Japan Earthquake with Mw: 9.0 occurred at 05:46:23 UTC with its epicenter estimated at 38.322_N, 142.369_E, and focal depth of 32 km (USGS, 2011). <span class="hlt">Tsunami</span> <span class="hlt">waves</span> <span class="hlt">propagated</span> in Pacific Ocean to all directions. At Russian coast the highest <span class="hlt">waves</span> were observed in the Kuril Islands (Malokurilskoye, Kunashir Island) which located in between Pacific ocean and the Okhotsk Sea. Kuril island provides limited transmission of <span class="hlt">tsunami</span> <span class="hlt">waves</span> from Pacific ocean. <span class="hlt">tsunami</span> In 2011 Great East Japan Earthquake and <span class="hlt">Tsunami</span> event, the maximum amplitude of the <span class="hlt">tsunami</span> was observed as 3 m in Kuril islands. However, <span class="hlt">tsunami</span> arrived Okhotsk Sea losing a significant amount of energy. Therefore the <span class="hlt">tsunami</span> amplitudes at the coast of the Okhotsk Sea were smaller. In order to estimate the level of energy loss while passing through the narrow straits of the Kuril Islands, a series of numerical simulations was done by using <span class="hlt">tsunami</span> numerical code NAMI DANCE. Ten largest earthquake shocks capable of generating <span class="hlt">tsunami</span> were used as inputs of <span class="hlt">tsunami</span> sources in the modeling. Hence the relation between the transmission of <span class="hlt">tsunami</span> and the dimensions of the straits are compared and discussed. Finally the characteristics of <span class="hlt">tsunami</span> <span class="hlt">propagation</span> (arrival time and coastal amplification) at the coast in the Okhotsk Sea. The varying grid structure is used in numerical modeling in order to make finer analysis of <span class="hlt">tsunami</span> passing through narrow straits of the Kuril Islands. This allows to combine exactly the installation locations of stationary and computational gauges. The simulation results are compared with the observations. The linear form of shallow water equations are used in the deep ocean region offshore part of the Sea of Okhotsk. Boussinesq type equations were also used at the near shore area in simulations. Since the Okhotsk Sea Results are a semi enclosed basin, the reflection characteristics at the coastal boundaries may be important. The numerical experiments are also</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16266186','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16266186"><span>Modeling elastic <span class="hlt">wave</span> <span class="hlt">propagation</span> in kidney stones with application to shock <span class="hlt">wave</span> lithotripsy.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cleveland, Robin O; Sapozhnikov, Oleg A</p> <p>2005-10-01</p> <p>A time-domain finite-difference solution to the equations of linear elasticity was used to model the <span class="hlt">propagation</span> of lithotripsy <span class="hlt">waves</span> in kidney stones. The model was used to determine the loading on the stone (principal stresses and strains and maximum shear stresses and strains) due to the impact of lithotripsy shock <span class="hlt">waves</span>. The simulations show that the peak loading induced in kidney stones is generated by constructive interference from shear <span class="hlt">waves</span> launched from the outer edge of the stone with other <span class="hlt">waves</span> in the stone. Notably the shear <span class="hlt">wave</span> induced loads were significantly larger than the loads generated by the classic Hopkinson or spall effect. For simulations where the diameter of the focal spot of the lithotripter was smaller than that of the stone the loading decreased by more than 50%. The constructive interference was also sensitive to shock rise time and it was found that the peak tensile stress reduced by 30% as rise time increased from 25 to 150 ns. These results demonstrate that shear <span class="hlt">waves</span> likely play a critical role in stone comminution and that lithotripters with large focal widths and short rise times should be effective at generating high stresses inside kidney stones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1814120S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1814120S"><span>Seismic <span class="hlt">wave</span> <span class="hlt">propagation</span> through an extrusive basalt sequence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sanford, Oliver; Hobbs, Richard; Brown, Richard; Schofield, Nick</p> <p>2016-04-01</p> <p>Layers of basalt flows within sedimentary successions (e.g. in the Faeroe-Shetland Basin) cause complex scattering and attenuation of seismic <span class="hlt">waves</span> during seismic exploration surveys. Extrusive basaltic sequences are highly heterogeneous and contain strong impedance contrasts between higher velocity crystalline flow cores (˜6 km s-1) and the lower velocity fragmented and weathered flow crusts (3-4 km s-1). Typically, the refracted <span class="hlt">wave</span> from the basaltic layer is used to build a velocity model by tomography. This velocity model is then used to aid processing of the reflection data where direct determination of velocity is ambiguous, or as a starting point for full waveform inversion, for example. The model may also be used as part of assessing drilling risk of potential wells, as it is believed to constrain the total thickness of the sequence. In heterogeneous media, where the scatter size is of the order of the seismic wavelength or larger, scattering preferentially traps the seismic energy in the low velocity regions. This causes a build-up of energy that is guided along the low velocity layers. This has implications for the interpretation of the observed first arrival of the seismic <span class="hlt">wave</span>, which may be a biased towards the low velocity regions. This will then lead to an underestimate of the velocity structure and hence the thickness of the basalt, with implications for the drilling of wells hoping to penetrate through the base of the basalts in search of hydrocarbons. Using 2-D acoustic finite difference modelling of the guided <span class="hlt">wave</span> through a simple layered basalt sequence, we consider the relative importance of different parameters of the basalt on the seismic energy <span class="hlt">propagating</span> through the layers. These include the proportion of high to low velocity material, the number of layers, their thickness and the roughness of the interfaces between the layers. We observe a non-linear relationship between the ratio of high to low velocity layers and the apparent velocity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999JMP....40..511P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999JMP....40..511P"><span><span class="hlt">Propagation</span> estimates for dispersive <span class="hlt">wave</span> equations: Application to the stratified <span class="hlt">wave</span> equation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pravica, David W.</p> <p>1999-01-01</p> <p>The plane-stratified <span class="hlt">wave</span> equation (∂t2+H)ψ=0 with H=-c(y)2∇z2 is studied, where z=x⊕y, x∈Rk, y∈R1 and |c(y)-c∞|→0 as |y|→∞. Solutions to such an equation are solved for the <span class="hlt">propagation</span> of <span class="hlt">waves</span> through a layered medium and can include <span class="hlt">waves</span> which <span class="hlt">propagate</span> in the x-directions only (i.e., trapped modes). This leads to a consideration of the pseudo-differential <span class="hlt">wave</span> equation (∂t2+ω(-Δx))ψ=0 such that the dispersion relation ω(ξ2) is analytic and satisfies c1⩽ω'(ξ2)⩽c2 for c*>0. Uniform <span class="hlt">propagation</span> estimates like ∫|x|⩽|t|αE(UtP±φ0)dkx⩽Cα,β(1+|t|)-β∫E(φ0)dkx are obtained where Ut is the evolution group, P± are projection operators onto the Hilbert space of initial conditions φ∈H and E(ṡ) is the local energy density. In special cases scattering of trapped modes off a local perturbation satisfies the causality estimate ||P+ρΛjSP-ρΛk||⩽Cνρ-ν for each ν<1/2. Here P+ρΛj (P-ρΛk) are remote outgoing/detector (incoming/transmitter) projections for the jth (kth) trapped mode. Also Λ⋐R+ is compact, so the projections localize onto formally-incoming (eventually-outgoing) states.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.G33A0830U','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.G33A0830U"><span>Modeling influence of tide stages on forecasts of the 2010 Chilean <span class="hlt">tsunami</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Uslu, B. U.; Chamberlin, C.; Walsh, D.; Eble, M. C.</p> <p>2010-12-01</p> <p>The impact of the 2010 Chilean <span class="hlt">tsunami</span> is studied using the NOAA high-resolution <span class="hlt">tsunami</span> forecast model augmented to include modeled tide heights in addition to deep-water <span class="hlt">tsunami</span> <span class="hlt">propagation</span> as boundary-condition input. The Chilean <span class="hlt">tsunami</span> was observed at the Los Angeles tide station at mean low water, Hilo at low, Pago Pago at mid tide and Wake Island near high tide. Because the <span class="hlt">tsunami</span> arrived at coastal communities at a representative variety of tide stages, 2010 Chile <span class="hlt">tsunami</span> provides opportunity to study the <span class="hlt">tsunami</span> impacts at different tide levels to different communities. The current forecast models are computed with a constant tidal stage, and this study evaluates techniques for adding an additional varying predicted tidal component in a forecasting context. Computed <span class="hlt">wave</span> amplitudes, <span class="hlt">wave</span> currents and flooding are compared at locations around the Pacific, and the difference in <span class="hlt">tsunami</span> impact due to tidal stage is studied. This study focuses on how <span class="hlt">tsunami</span> impacts vary with different tide levels, and helps us understand how the inclusion of tidal components can improve real-time forecast accuracy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JPhCS.656a2023K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JPhCS.656a2023K"><span>Study on Pressure <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in a Liquid Containing Spherical Bubbles in a Rectangular Duct</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kawahara, Junya; Watanabe, Masao; Kobayashi, Kazumichi</p> <p>2015-12-01</p> <p>Pressure <span class="hlt">wave</span> <span class="hlt">propagation</span> in a liquid containing several bubbles is numerically investigated. We simulate liner plane <span class="hlt">wave</span> <span class="hlt">propagation</span> in a liquid containing 10 spherical bubbles in a rectangular duct with the equation of motion for N spherical bubbles. The sound pressures of the reflected <span class="hlt">waves</span> from the rigid walls are calculated by using the method of images. The result shows that the phase velocity of the pressure <span class="hlt">wave</span> <span class="hlt">propagating</span> in the liquid containing 10 spherical bubbles in the duct agrees well with the low-frequency speed of sound in a homogeneous bubbly liquid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMSA33B..04T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMSA33B..04T"><span>Earthquake- and <span class="hlt">tsunami</span>-induced ionospheric disturbances detected by GPS total electron content observation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tsugawa, T.; Nishioka, M.; Matsumura, M.; Shinagawa, H.; Maruyama, T.; Ogawa, T.; Saito, A.; Otsuka, Y.; Nagatsuma, T.; Murata, T.</p> <p>2012-12-01</p> <p>Ionospheric disturbances induced by the 2011 Tohoku earthquake and <span class="hlt">tsunami</span> were studied by the high-resolution GPS total electron content (TEC) observation in Japan and in the world. The initial ionospheric disturbance appeared as sudden depletions by about 6 TEC unit (20%) about seven minutes after the earthquake onset, near the epicenter. From 06:00UT to 06:15UT, circular <span class="hlt">waves</span> with short <span class="hlt">propagation</span> distance <span class="hlt">propagated</span> in the radial direction in the <span class="hlt">propagation</span> velocity of 3,457, 783, 423 m/s for the first, second, third peak, respectively. Following these <span class="hlt">waves</span>, concentric <span class="hlt">waves</span> with long <span class="hlt">propagation</span> distance appeared to <span class="hlt">propagate</span> at the velocity of 138-288 m/s. In the vicinity of the epicenter, shortperiod oscillations with period of about 4 minutes were observed after 06:00 UT for 3 hours or more. We focus on the the circular and concentric <span class="hlt">waves</span> in this paper. The circular or concentric structures indicate that these ionospheric disturbances had a point source. The center of these structures, termed as "ionospheric epicenter", was located around 37.5 deg N of latitude and 144.0 deg E of longitude, 170 km far from the epicenter to the southeast direction, and corresponded to the <span class="hlt">tsunami</span> source. Comparing to the results of a numerical simulation using non-hydrostatic compressible atmosphere-ionosphere model, the first peak of circular <span class="hlt">wave</span> would be caused by the acoustic <span class="hlt">waves</span> generated from the <span class="hlt">propagating</span> Rayleigh <span class="hlt">wave</span>. The second and third <span class="hlt">waves</span> would be caused by atmospheric gravity <span class="hlt">waves</span> excited in the lower ionosphere due to the acoustic <span class="hlt">wave</span> <span class="hlt">propagations</span> from the <span class="hlt">tsunami</span> source. The fourth and following <span class="hlt">waves</span> are considered to be caused by the atmospheric gravity <span class="hlt">waves</span> induced by the wavefronts of traveling <span class="hlt">tsunami</span>. Long-<span class="hlt">propagation</span> of these TEC disturbances were studied also using high-resolution GPS-TEC data in North America and Europe. Medium-scale <span class="hlt">wave</span> structures with wavelengths of several 100 km appeared in the west part of North America at the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSM42A..03H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSM42A..03H"><span><span class="hlt">Propagation</span> and Linear Mode Conversion of Magnetosonic and Electromagnetic Ion Cyclotron <span class="hlt">Waves</span> in the Radiation Belts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Horne, R. B.; Yoshizumi, M.</p> <p>2017-12-01</p> <p>Magnetosonic <span class="hlt">waves</span> and electromagnetic ion cyclotron (EMIC) <span class="hlt">waves</span> are important for electron acceleration and loss from the radiation belts. It is generally understood that these <span class="hlt">waves</span> are generated by unstable ion distributions that form during geomagnetically disturbed times. Here we show that magnetosonic <span class="hlt">waves</span> could be a source of EMIC <span class="hlt">waves</span> as a result of <span class="hlt">propagation</span> and a process of linear mode conversion. The converse is also possible. We present ray tracing to show how magnetosonic (EMIC) <span class="hlt">waves</span> launched with large (small) <span class="hlt">wave</span> normal angles can reach a location where the <span class="hlt">wave</span> normal angle is zero and the <span class="hlt">wave</span> frequency equals the so-called cross-over frequency whereupon energy can be converted from one mode to another without attenuation. While EMIC <span class="hlt">waves</span> could be a source of magnetosonic <span class="hlt">waves</span> below the cross-over frequency magnetosonic <span class="hlt">waves</span> could be a source of hydrogen band <span class="hlt">waves</span> but not helium band <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/20995674-evaluation-numerical-simulation-tsunami-coastal-nuclear-power-plants-india','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/20995674-evaluation-numerical-simulation-tsunami-coastal-nuclear-power-plants-india"><span>Evaluation and Numerical Simulation of <span class="hlt">Tsunami</span> for Coastal Nuclear Power Plants of India</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sharma, Pavan K.; Singh, R.K.; Ghosh, A.K.</p> <p>2006-07-01</p> <p>Recent <span class="hlt">tsunami</span> generated on December 26, 2004 due to Sumatra earthquake of magnitude 9.3 resulted in inundation at the various coastal sites of India. The site selection and design of Indian nuclear power plants demand the evaluation of run up and the structural barriers for the coastal plants: Besides it is also desirable to evaluate the early warning system for <span class="hlt">tsunami</span>-genic earthquakes. The <span class="hlt">tsunamis</span> originate from submarine faults, underwater volcanic activities, sub-aerial landslides impinging on the sea and submarine landslides. In case of a submarine earthquake-induced <span class="hlt">tsunami</span> the <span class="hlt">wave</span> is generated in the fluid domain due to displacement of themore » seabed. There are three phases of <span class="hlt">tsunami</span>: generation, <span class="hlt">propagation</span>, and run-up. Reactor Safety Division (RSD) of Bhabha Atomic Research Centre (BARC), Trombay has initiated computational simulation for all the three phases of <span class="hlt">tsunami</span> source generation, its <span class="hlt">propagation</span> and finally run up evaluation for the protection of public life, property and various industrial infrastructures located on the coastal regions of India. These studies could be effectively utilized for design and implementation of early warning system for coastal region of the country apart from catering to the needs of Indian nuclear installations. This paper presents some results of <span class="hlt">tsunami</span> <span class="hlt">waves</span> based on different analytical/numerical approaches with shallow water <span class="hlt">wave</span> theory. (authors)« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29026879','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29026879"><span><span class="hlt">Tsunamis</span> in the geological record: Making <span class="hlt">waves</span> with a cautionary tale from the Mediterranean.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Marriner, Nick; Kaniewski, David; Morhange, Christophe; Flaux, Clément; Giaime, Matthieu; Vacchi, Matteo; Goff, James</p> <p>2017-10-01</p> <p>From 2000 to 2015, <span class="hlt">tsunamis</span> and storms killed more than 430,000 people worldwide and affected a further >530 million, with total damages exceeding US$970 billion. These alarming trends, underscored by the tragic events of the 2004 Indian Ocean catastrophe, have fueled increased worldwide demands for assessments of past, present, and future coastal risks. Nonetheless, despite its importance for hazard mitigation, discriminating between storm and <span class="hlt">tsunami</span> deposits in the geological record is one of the most challenging and hotly contended topics in coastal geoscience. To probe this knowledge gap, we present a 4500-year reconstruction of "<span class="hlt">tsunami</span>" variability from the Mediterranean based on stratigraphic but not historical archives and assess it in relation to climate records and reconstructions of storminess. We elucidate evidence for previously unrecognized "<span class="hlt">tsunami</span> megacycles" with three peaks centered on the Little Ice Age, 1600, and 3100 cal. yr B.P. (calibrated years before present). These ~1500-year cycles, strongly correlated with climate deterioration in the Mediterranean/North Atlantic, challenge up to 90% of the original <span class="hlt">tsunami</span> attributions and suggest, by contrast, that most events are better ascribed to periods of heightened storminess. This timely and provocative finding is crucial in providing appropriately tailored assessments of coastal hazard risk in the Mediterranean and beyond.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..SHK.P7001N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..SHK.P7001N"><span>Shock <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Functionally Graded Mineralized Tissue</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nelms, Matthew; Hodo, Wayne; Livi, Ken; Browning, Alyssa; Crawford, Bryan; Rajendran, A. M.</p> <p>2017-06-01</p> <p>In this investigation, the effects of shock <span class="hlt">wave</span> <span class="hlt">propagation</span> in bone-like biomineralized tissue was investigated. The Alligator gar (Atractosteus spatula) exoskeleton is comprised of many disparate scales that provide a biological analog for potential design of flexible protective material systems. The gar scale is identified as a two-phase, (1) hydroxyapatite mineral and (2) collagen protein, biological composite with two distinct layers where a stiff, ceramic-like ganoine overlays a soft, highly ductile ganoid bone. Previous experimentations has shown significant softening under compressive loading and an asymmetrical stress-strain response for analogous mineralized tissues. The structural features, porosity, and elastic modulus were determined from high-resolution scanning electron microscopy, 3D micro-tomography, and dynamic nanoindentation experiments to develop an idealized computational model for FE simulations. The numerical analysis employed Gurson's yield criterion to determine the influence of porosity and pressure on material strength. Functional gradation of elastic moduli and certain structural features, such as the sawtooth interface, are explicitly modeled to study the plate impact shock profile for a full 3-D analysis using ABAQUS finite element software.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21973365','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21973365"><span>Resonances and <span class="hlt">wave</span> <span class="hlt">propagation</span> velocity in the subglottal airways.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lulich, Steven M; Alwan, Abeer; Arsikere, Harish; Morton, John R; Sommers, Mitchell S</p> <p>2011-10-01</p> <p>Previous studies of subglottal resonances have reported findings based on relatively few subjects, and the relations between these resonances, subglottal anatomy, and models of subglottal acoustics are not well understood. In this study, accelerometer signals of subglottal acoustics recorded during sustained [a:] vowels of 50 adult native speakers (25 males, 25 females) of American English were analyzed. The study confirms that a simple uniform tube model of subglottal airways, closed at the glottis and open at the inferior end, is appropriate for describing subglottal resonances. The main findings of the study are (1) whereas the walls may be considered rigid in the frequency range of Sg2 and Sg3, they are yielding and resonant in the frequency range of Sg1, with a resulting ~4/3 increase in <span class="hlt">wave</span> <span class="hlt">propagation</span> velocity and, consequently, in the frequency of Sg1; (2) the "acoustic length" of the equivalent uniform tube varies between 18 and 23.5 cm, and is approximately equal to the height of the speaker divided by an empirically determined scaling factor; (3) trachea length can also be predicted by dividing height by another empirically determined scaling factor; and (4) differences between the subglottal resonances of males and females can be accounted for by height-related differences. © 2011 Acoustical Society of America</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1435106-molecular-hydrodynamics-vortex-formation-sound-wave-propagation','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1435106-molecular-hydrodynamics-vortex-formation-sound-wave-propagation"><span>Molecular hydrodynamics: Vortex formation and sound <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Han, Kyeong Hwan; Kim, Changho; Talkner, Peter; ...</p> <p>2018-01-14</p> <p>In the present study, quantitative feasibility tests of the hydrodynamic description of a two-dimensional fluid at the molecular level are performed, both with respect to length and time scales. Using high-resolution fluid velocity data obtained from extensive molecular dynamics simulations, we computed the transverse and longitudinal components of the velocity field by the Helmholtz decomposition and compared them with those obtained from the linearized Navier-Stokes (LNS) equations with time-dependent transport coefficients. By investigating the vortex dynamics and the sound <span class="hlt">wave</span> <span class="hlt">propagation</span> in terms of these field components, we confirm the validity of the LNS description for times comparable to ormore » larger than several mean collision times. The LNS description still reproduces the transverse velocity field accurately at smaller times, but it fails to predict characteristic patterns of molecular origin visible in the longitudinal velocity field. Based on these observations, we validate the main assumptions of the mode-coupling approach. The assumption that the velocity autocorrelation function can be expressed in terms of the fluid velocity field and the tagged particle distribution is found to be remarkably accurate even for times comparable to or smaller than the mean collision time. This suggests that the hydrodynamic-mode description remains valid down to the molecular scale.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S51A2753H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S51A2753H"><span>Modeling Anisotropic Elastic <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Jointed Rock Masses</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hurley, R.; Vorobiev, O.; Ezzedine, S. M.; Antoun, T.</p> <p>2016-12-01</p> <p>We present a numerical approach for determining the anisotropic stiffness of materials with nonlinearly-compliant joints capable of sliding. The proposed method extends existing ones for upscaling the behavior of a medium with open cracks and inclusions to cases relevant to natural fractured and jointed rocks, where nonlinearly-compliant joints can undergo plastic slip. The method deviates from existing techniques by incorporating the friction and closure states of the joints, and recovers an anisotropic elastic form in the small-strain limit when joints are not sliding. We present the mathematical formulation of our method and use Representative Volume Element (RVE) simulations to evaluate its accuracy for joint sets with varying complexity. We then apply the formulation to determine anisotropic elastic constants of jointed granite found at the Nevada Nuclear Security Site (NNSS) where the Source Physics Experiments (SPE), a campaign of underground chemical explosions, are performed. Finally, we discuss the implementation of our numerical approach in a massively parallel Lagrangian code Geodyn-L and its use for studying <span class="hlt">wave</span> <span class="hlt">propagation</span> from underground explosions. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040074324&hterms=methods+quantitative&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmethods%2Bquantitative','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040074324&hterms=methods+quantitative&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmethods%2Bquantitative"><span>An Investigation of <span class="hlt">Wave</span> <span class="hlt">Propagations</span> in Discontinuous Galerkin Method</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hu, Fang Q.</p> <p>2004-01-01</p> <p>Analysis of the discontinuous Galerkin method has been carried out for one- and two-dimensional system of hyperbolic equations. Analytical, as well as numerical, properties of <span class="hlt">wave</span> <span class="hlt">propagation</span> in a DGM scheme are derived and verified with direct numerical simulations. In addition to a systematic examination of the dissipation and dispersion errors, behaviours of a DG scheme at an interface of two different grid topologies are also studied. Under the same framework, a quantitative discrete analysis of various artificial boundary conditions is also conducted. Progress has been made in numerical boundary condition treatment that is closely related to the application of DGM in aeroacoustics problems. Finally, Fourier analysis of DGM for the Convective diffusion equation has also be studied in connection with the application of DG schemes for the Navier-Stokes equations. This research has resulted in five(5) publications, plus one additional manuscript in preparation, four(4) conference presentations, and three(3) departmental seminars, as summarized in part II. Abstracts of papers are given in part 111 of this report.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1435106-molecular-hydrodynamics-vortex-formation-sound-wave-propagation','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1435106-molecular-hydrodynamics-vortex-formation-sound-wave-propagation"><span>Molecular hydrodynamics: Vortex formation and sound <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Han, Kyeong Hwan; Kim, Changho; Talkner, Peter</p> <p></p> <p>In the present study, quantitative feasibility tests of the hydrodynamic description of a two-dimensional fluid at the molecular level are performed, both with respect to length and time scales. Using high-resolution fluid velocity data obtained from extensive molecular dynamics simulations, we computed the transverse and longitudinal components of the velocity field by the Helmholtz decomposition and compared them with those obtained from the linearized Navier-Stokes (LNS) equations with time-dependent transport coefficients. By investigating the vortex dynamics and the sound <span class="hlt">wave</span> <span class="hlt">propagation</span> in terms of these field components, we confirm the validity of the LNS description for times comparable to ormore » larger than several mean collision times. The LNS description still reproduces the transverse velocity field accurately at smaller times, but it fails to predict characteristic patterns of molecular origin visible in the longitudinal velocity field. Based on these observations, we validate the main assumptions of the mode-coupling approach. The assumption that the velocity autocorrelation function can be expressed in terms of the fluid velocity field and the tagged particle distribution is found to be remarkably accurate even for times comparable to or smaller than the mean collision time. This suggests that the hydrodynamic-mode description remains valid down to the molecular scale.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..SHK.U7002P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..SHK.U7002P"><span>Stress <span class="hlt">wave</span> <span class="hlt">propagation</span> and mitigation in two polymeric foams</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pradel, Pierre; Malaise, Frederic; Cadilhon, Baptiste; Quessada, Jean-Hugues; de Resseguier, Thibaut; Delhomme, Catherine; Le Blanc, Gael</p> <p>2017-06-01</p> <p>Polymeric foams are widely used in industry for thermal insulation or shock mitigation. This paper investigates the ability of a syntactic epoxy foam and an expanded polyurethane foam to mitigate intense (several GPa) and short duration (<10-6 s) stress pulses. Plate impact and electron beam irradiation experiments have been conducted to study the dynamic mechanical responses of both foams. Interferometer Doppler Laser method is used to record the target rear surface velocity. A two-<span class="hlt">wave</span> structure associated with the <span class="hlt">propagation</span> of an elastic precursor followed by the compaction of the pores has been observed. The compaction stress level deduced from the velocity measurement is a good indicator of mitigation capability of the foams. Quasi-static tests and dynamic soft recovery experiments have also been performed to determine the compaction mechanisms. In the polyurethane foam, the pores are closed by elastic buckling of the matrix and damage of the structure. In the epoxy foam, the compaction is due to the crushing of glass microspheres. Two porous material models successfully represent the macroscopic response of these polymeric foams.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOS.A34C2673S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOS.A34C2673S"><span><span class="hlt">Wave</span> Measurements in Landfast Ice in Svalbard: Evolution of <span class="hlt">Wave</span> <span class="hlt">Propagation</span> following Wind <span class="hlt">Waves</span> to Swell Transition</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sutherland, G.; Rabault, J.; Jensen, A.; Christensen, K. H.; Ward, B.; Marchenko, A. V.; Morozov, E.; Gundersen, O.; Halsne, T.; Lindstrøm, E.</p> <p>2016-02-01</p> <p>The impact of sea-ice cover on <span class="hlt">propagation</span> of water <span class="hlt">waves</span> has been studied over five decades, both theoretically and from measurements on the ice. Understanding the interaction between water <span class="hlt">waves</span> and sea-ice covers is a topic of interest for a variety of purposes such as formulation of ocean models for climate, weather and sea state predictions, and the analysis of pollution dispersion in the Arctic. Our knowledge of the underlying phenomena is still partial, and more experimental data is required to gain further insight into the associated physics. Three Inertial Motion Units (IMUs) have been assessed in the lab and used to perform measurements on landfast ice over 2 days in Tempelfjorden, Svalbard during March 2015. The ice thickness in the measurement area was approximately 60 to 80 cm. Two IMUs were located close to each other (6 meters) at a distance around 180 m from the ice edge. The third IMU was placed 120 m from the ice edge. The data collected contains a transition from high frequency, wind generated <span class="hlt">waves</span> to lower frequency swell. Drastic changes in <span class="hlt">wave</span> <span class="hlt">propagation</span> are observed in relation with this transition. The level of reflected energy obtained from rotational spectra is much higher before the transition to low frequency swell than later on. The correlation between the signal recorded by the IMU closer to the ice edge and the two others IMUs is low during the wind <span class="hlt">waves</span> dominated period, and increases with incoming swell. The dispersion relation for <span class="hlt">waves</span> in ice was found to correspond to flexural-gravity <span class="hlt">waves</span> before the transition and deepwater gravity <span class="hlt">waves</span> afterwards.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRA..122.7742B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRA..122.7742B"><span>Origin of the ahead of <span class="hlt">tsunami</span> traveling ionospheric disturbances during Sumatra <span class="hlt">tsunami</span> and offshore forecasting</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bagiya, Mala S.; Kherani, E. A.; Sunil, P. S.; Sunil, A. S.; Sunda, S.; Ramesh, D. S.</p> <p>2017-07-01</p> <p>The presence of ionospheric disturbances associated with Sumatra 2004 <span class="hlt">tsunami</span> that <span class="hlt">propagated</span> ahead of <span class="hlt">tsunami</span> itself has previously been identified. However, their origin remains unresolved till date. Focusing on their origin mechanism, we document these ionospheric disturbances referred as Ahead of <span class="hlt">tsunami</span> Traveling Ionospheric Disturbances (ATIDs). Using total electron content (TEC) data from GPS Aided GEO Augmented Navigation GPS receivers located near the Indian east coast, we first confirm the ATIDs presence in TEC that appear 90 min ahead of the arrival of <span class="hlt">tsunami</span> at the Indian east coast. We propose here a simulation study based on <span class="hlt">tsunami</span>-atmospheric-ionospheric coupling that considers tsunamigenic acoustic gravity <span class="hlt">waves</span> (AGWs) to excite these disturbances. We explain the ATIDs generation based on the dissipation of transverse mode of the primary AGWs. The simulation corroborates the excitation of ATIDs with characteristics similar to the observations. Therefore, we offer an alternative theoretical tool to monitor the offshore ATIDs where observations are either rare or not available and could be potentially important for the <span class="hlt">tsunami</span> early warning.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S51A2750L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S51A2750L"><span>Coupling Hydrodynamic and <span class="hlt">Wave</span> <span class="hlt">Propagation</span> Codes for Modeling of Seismic <span class="hlt">Waves</span> recorded at the SPE Test.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Larmat, C. S.; Rougier, E.; Delorey, A.; Steedman, D. W.; Bradley, C. R.</p> <p>2016-12-01</p> <p>The goal of the Source Physics Experiment (SPE) is to bring empirical and theoretical advances to the problem of detection and identification of underground nuclear explosions. For this, the SPE program includes a strong modeling effort based on first principles calculations with the challenge to capture both the source and near-source processes and those taking place later in time as seismic <span class="hlt">waves</span> <span class="hlt">propagate</span> within complex 3D geologic environments. In this paper, we report on results of modeling that uses hydrodynamic simulation codes (Abaqus and CASH) coupled with a 3D full waveform <span class="hlt">propagation</span> code, SPECFEM3D. For modeling the near source region, we employ a fully-coupled Euler-Lagrange (CEL) modeling capability with a new continuum-based visco-plastic fracture model for simulation of damage processes, called AZ_Frac. These capabilities produce high-fidelity models of various factors believed to be key in the generation of seismic <span class="hlt">waves</span>: the explosion dynamics, a weak grout-filled borehole, the surrounding jointed rock, and damage creation and deformations happening around the source and the free surface. SPECFEM3D, based on the Spectral Element Method (SEM) is a direct numerical method for full <span class="hlt">wave</span> modeling with mathematical accuracy. The coupling interface consists of a series of grid points of the SEM mesh situated inside of the hydrodynamic code's domain. Displacement time series at these points are computed using output data from CASH or Abaqus (by interpolation if needed) and fed into the time marching scheme of SPECFEM3D. We will present validation tests with the Sharpe's model and comparisons of waveforms modeled with Rg <span class="hlt">waves</span> (2-8Hz) that were recorded up to 2 km for SPE. We especially show effects of the local topography, velocity structure and spallation. Our models predict smaller amplitudes of Rg <span class="hlt">waves</span> for the first five SPE shots compared to pure elastic models such as Denny &Johnson (1991).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH23A0194A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH23A0194A"><span>Preliminary Hazard Assessment for Tectonic <span class="hlt">Tsunamis</span> in the Eastern Mediterranean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aydin, B.; Bayazitoglu, O.; Sharghi vand, N.; Kanoglu, U.</p> <p>2017-12-01</p> <p>There are many critical industrial facilities such as energy production units and energy transmission lines along the southeast coast of Turkey. This region is also active on tourism, and agriculture and aquaculture production. There are active faults in the region, i.e. the Cyprus Fault, which extends along the Mediterranean basin in the east-west direction and connects to the Hellenic Arc. Both the Cyprus Fault and the Hellenic Arc are seismologically active and are capable of generating earthquakes with tsunamigenic potential. Even a small <span class="hlt">tsunami</span> in the region could cause confusion as shown by the recent 21 July 2017 earthquake of Mw 6.6, which occurred in the Aegean Sea, between Bodrum, Turkey and Kos Island, Greece since region is not prepared for such an event. Moreover, the Mediterranean Sea is one of the most vulnerable regions against sea level rise due to global warming, according to the 5th Report of the Intergovernmental Panel on Climate Change. For these reasons, a marine hazard such as a <span class="hlt">tsunami</span> can cause much worse damage than expected in the region (Kanoglu et al., Phil. Trans. R. Soc. A 373, 2015). Hence, <span class="hlt">tsunami</span> hazard assessment is required for the region. In this study, we first characterize earthquakes which have potential to generate a <span class="hlt">tsunami</span> in the Eastern Mediterranean. Such study is a prerequisite for regional <span class="hlt">tsunami</span> mitigation studies. For fast and timely predictions, <span class="hlt">tsunami</span> warning systems usually employ databases that store pre-computed <span class="hlt">tsunami</span> <span class="hlt">propagation</span> resulting from hypothetical earthquakes with pre-defined parameters. These pre-defined sources are called <span class="hlt">tsunami</span> unit sources and they are linearly superposed to mimic a real event, since <span class="hlt">wave</span> <span class="hlt">propagation</span> is linear offshore. After investigating historical earthquakes along the Cyprus Fault and the Hellenic Arc, we identified tsunamigenic earthquakes in the Eastern Mediterranean and proposed <span class="hlt">tsunami</span> unit sources for the region. We used the <span class="hlt">tsunami</span> numerical model MOST (Titov et al</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PApGe.tmp..437G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PApGe.tmp..437G"><span>Coastal Amplification Laws for the French <span class="hlt">Tsunami</span> Warning Center: Numerical Modeling and Fast Estimate of <span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Heights Along the French Riviera</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gailler, A.; Hébert, H.; Schindelé, F.; Reymond, D.</p> <p>2017-11-01</p> <p><span class="hlt">Tsunami</span> modeling tools in the French <span class="hlt">tsunami</span> Warning Center operational context provide rapidly derived warning levels with a dimensionless variable at basin scale. A new forecast method based on coastal amplification laws has been tested to estimate the <span class="hlt">tsunami</span> onshore height, with a focus on the French Riviera test-site (Nice area). This fast prediction tool provides a coastal <span class="hlt">tsunami</span> height distribution, calculated from the numerical simulation of the deep ocean <span class="hlt">tsunami</span> amplitude and using a transfer function derived from the Green's law. Due to a lack of <span class="hlt">tsunami</span> observations in the western Mediterranean basin, coastal amplification parameters are here defined regarding high resolution nested grids simulations. The preliminary results for the Nice test site on the basis of nine historical and synthetic sources show a good agreement with the time-consuming high resolution modeling: the linear approximation is obtained within 1 min in general and provides estimates within a factor of two in amplitude, although the resonance effects in harbors and bays are not reproduced. In Nice harbor especially, variation in <span class="hlt">tsunami</span> amplitude is something that cannot be really assessed because of the magnitude range and maximum energy azimuth of possible events to account for. However, this method is well suited for a fast first estimate of the coastal <span class="hlt">tsunami</span> threat forecast.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH23A0198G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH23A0198G"><span>Coastal amplification laws for the French <span class="hlt">tsunami</span> Warning Center: numerical modeling and fast estimate of <span class="hlt">tsunami</span> <span class="hlt">wave</span> heights along the French Riviera</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gailler, A.; Schindelé, F.; Hebert, H.; Reymond, D.</p> <p>2017-12-01</p> <p><span class="hlt">Tsunami</span> modeling tools in the French <span class="hlt">tsunami</span> Warning Center operational context provide for now warning levels with a no dimension scale, and at basin scale. A new forecast method based on coastal amplification laws has been tested to estimate the <span class="hlt">tsunami</span> onshore height, with a focus on the French Riviera test-site (Nice area). This fast prediction tool provides a coastal <span class="hlt">tsunami</span> height distribution, calculated from the numerical simulation of the deep ocean <span class="hlt">tsunami</span> amplitude and using a transfer function derived from the Green's law. Due to a lack of <span class="hlt">tsunami</span> observation in the western Mediterranean basin, coastal amplification parameters are here defined regarding high resolution nested grids simulations. The first encouraging results for the Nice test site on the basis of 9 historical and fake sources show a good agreement with the time-consuming high resolution modeling: the linear approximation provides within in general 1 minute estimates less a factor of 2 in amplitude, although the resonance effects in harbors and bays are not reproduced. In Nice harbor especially, variation in <span class="hlt">tsunami</span> amplitude is something that cannot be really appreciated because of the magnitude range and maximum energy azimuth of possible events to account for. However, this method suits well for a fast first estimate of the coastal <span class="hlt">tsunami</span> threat forecast.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PApGe.175.1429G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PApGe.175.1429G"><span>Coastal Amplification Laws for the French <span class="hlt">Tsunami</span> Warning Center: Numerical Modeling and Fast Estimate of <span class="hlt">Tsunami</span> <span class="hlt">Wave</span> Heights Along the French Riviera</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gailler, A.; Hébert, H.; Schindelé, F.; Reymond, D.</p> <p>2018-04-01</p> <p><span class="hlt">Tsunami</span> modeling tools in the French <span class="hlt">tsunami</span> Warning Center operational context provide rapidly derived warning levels with a dimensionless variable at basin scale. A new forecast method based on coastal amplification laws has been tested to estimate the <span class="hlt">tsunami</span> onshore height, with a focus on the French Riviera test-site (Nice area). This fast prediction tool provides a coastal <span class="hlt">tsunami</span> height distribution, calculated from the numerical simulation of the deep ocean <span class="hlt">tsunami</span> amplitude and using a transfer function derived from the Green's law. Due to a lack of <span class="hlt">tsunami</span> observations in the western Mediterranean basin, coastal amplification parameters are here defined regarding high resolution nested grids simulations. The preliminary results for the Nice test site on the basis of nine historical and synthetic sources show a good agreement with the time-consuming high resolution modeling: the linear approximation is obtained within 1 min in general and provides estimates within a factor of two in amplitude, although the resonance effects in harbors and bays are not reproduced. In Nice harbor especially, variation in <span class="hlt">tsunami</span> amplitude is something that cannot be really assessed because of the magnitude range and maximum energy azimuth of possible events to account for. However, this method is well suited for a fast first estimate of the coastal <span class="hlt">tsunami</span> threat forecast.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012SCPMA..55.1172Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012SCPMA..55.1172Q"><span>The effective <span class="hlt">propagation</span> constants of SH <span class="hlt">wave</span> in composites reinforced by dispersive parallel nanofibers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Qiang, FangWei; Wei, PeiJun; Li, Li</p> <p>2012-07-01</p> <p>In the present paper, the effective <span class="hlt">propagation</span> constants of elastic SH <span class="hlt">waves</span> in composites with randomly distributed parallel cylindrical nanofibers are studied. The surface stress effects are considered based on the surface elasticity theory and non-classical interfacial conditions between the nanofiber and the host are derived. The scattering <span class="hlt">waves</span> from individual nanofibers embedded in an infinite elastic host are obtained by the plane <span class="hlt">wave</span> expansion method. The scattering <span class="hlt">waves</span> from all fibers are summed up to obtain the multiple scattering <span class="hlt">waves</span>. The interactions among random dispersive nanofibers are taken into account by the effective field approximation. The effective <span class="hlt">propagation</span> constants are obtained by the configurational average of the multiple scattering <span class="hlt">waves</span>. The effective speed and attenuation of the averaged <span class="hlt">wave</span> and the associated dynamical effective shear modulus of composites are numerically calculated. Based on the numerical results, the size effects of the nanofibers on the effective <span class="hlt">propagation</span> constants and the effective modulus are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMOS43D1334S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMOS43D1334S"><span>The Contribution of Coseismic Displacements due to Splay Faults Into the Local Wavefield of the 1964 Alaska <span class="hlt">Tsunami</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Suleimani, E.; Ruppert, N.; Fisher, M.; West, D.; Hansen, R.</p> <p>2008-12-01</p> <p>The Alaska Earthquake Information Center conducts <span class="hlt">tsunami</span> inundation mapping for coastal communities in Alaska. For many locations in the Gulf of Alaska, the 1964 <span class="hlt">tsunami</span> generated by the Mw9.2 Great Alaska earthquake may be the worst-case <span class="hlt">tsunami</span> scenario. We use the 1964 <span class="hlt">tsunami</span> observations to verify our numerical model of <span class="hlt">tsunami</span> <span class="hlt">propagation</span> and runup, therefore it is essential to use an adequate source function of the 1964 earthquake to reduce the level of uncertainty in the modeling results. It was shown that the 1964 co-seismic slip occurred both on the megathrust and crustal splay faults (Plafker, 1969). Plafker (2006) suggested that crustal faults were a major contributor to vertical displacements that generated local <span class="hlt">tsunami</span> <span class="hlt">waves</span>. Using eyewitness arrival times of the highest observed <span class="hlt">waves</span>, he suggested that the initial <span class="hlt">tsunami</span> <span class="hlt">wave</span> was higher and closer to the shore, than if it was generated by slip on the megathrust. We conduct a numerical study of two different source functions of the 1964 <span class="hlt">tsunami</span> to test whether the crustal splay faults had significant effects on local <span class="hlt">tsunami</span> runup heights and arrival times. The first source function was developed by Johnson et al. (1996) through joint inversion of the far-field <span class="hlt">tsunami</span> waveforms and geodetic data. The authors did not include crustal faults in the inversion, because the contribution of these faults to the far-field <span class="hlt">tsunami</span> was negligible. The second is the new coseismic displacement model developed by Suito and Freymueller (2008, submitted). This model extends the Montague Island fault farther along the Kenai Peninsula coast and thus reduces slip on the megathrust in that region. We also use an improved geometry of the Patton Bay fault based on the deep crustal seismic reflection and earthquake data. We <span class="hlt">propagate</span> <span class="hlt">tsunami</span> <span class="hlt">waves</span> generated by both source models across the Pacific Ocean and record <span class="hlt">wave</span> amplitudes at the locations of the tide gages that recorded the 1964 <span class="hlt">tsunami</span>. As expected, the two</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/5757343-slow-wave-propagation-monolithic-microwave-integrated-circuits-layered-non-layered-structures','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/5757343-slow-wave-propagation-monolithic-microwave-integrated-circuits-layered-non-layered-structures"><span>Slow-<span class="hlt">wave</span> <span class="hlt">propagation</span> on monolithic microwave integrated circuits with layered and non-layered structures</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Tzuang, C.K.C.</p> <p>1986-01-01</p> <p>Various MMIC (monolithic microwave integrated circuit) planar waveguides have shown possible existence of a slow-<span class="hlt">wave</span> <span class="hlt">propagation</span>. In many practical applications of these slow-<span class="hlt">wave</span> circuits, the semiconductor devices have nonuniform material properties that may affect the slow-<span class="hlt">wave</span> <span class="hlt">propagation</span>. In the first part of the dissertation, the effects of the nonuniform material properties are studied by a finite-element method. In addition, the transient pulse excitations of these slow-<span class="hlt">wave</span> circuits also have great theoretical and practical interests. In the second part, the time-domain analysis of a slow-<span class="hlt">wave</span> coplanar waveguide is presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28389057','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28389057"><span>Acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span> in bubbly flow with gas, vapor or their mixtures.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Yuning; Guo, Zhongyu; Gao, Yuhang; Du, Xiaoze</p> <p>2018-01-01</p> <p>Presence of bubbles in liquids could significantly alter the acoustic <span class="hlt">waves</span> in terms of <span class="hlt">wave</span> speed and attenuation. In the present paper, acoustic <span class="hlt">wave</span> <span class="hlt">propagation</span> in bubbly flows with gas, vapor and gas/vapor mixtures is theoretically investigated in a wide range of parameters (including frequency, bubble radius, void fraction, and vapor mass fraction). Our finding reveals two types of <span class="hlt">wave</span> <span class="hlt">propagation</span> behavior depending on the vapor mass fraction. Furthermore, the minimum <span class="hlt">wave</span> speed (required for the closure of cavitation modelling in the sonochemical reactor design) is analyzed and the influences of paramount parameters on it are quantitatively discussed. Copyright © 2017 Elsevier B.V. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730021203','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730021203"><span>A critical survey of <span class="hlt">wave</span> <span class="hlt">propagation</span> and impact in composite materials</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Moon, F. C.</p> <p>1973-01-01</p> <p>A review of the field of stress <span class="hlt">waves</span> in composite materials is presented covering the period up to December 1972. The major properties of <span class="hlt">waves</span> in composites are discussed and a summary is made of the major experimental results in this field. Various theoretical models for analysis of <span class="hlt">wave</span> <span class="hlt">propagation</span> in laminated, fiber and particle reinforced composites are surveyed. The anisotropic, dispersive and dissipative properties of stress pulses and shock <span class="hlt">waves</span> in such materials are reviewed. A review of the behavior of composites under impact loading is presented along with the application of <span class="hlt">wave</span> <span class="hlt">propagation</span> concepts to the determination of impact stresses in composite plates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=hemodynamics&id=EJ1131094','ERIC'); return false;" href="https://eric.ed.gov/?q=hemodynamics&id=EJ1131094"><span>Laboratory Model of the Cardiovascular System for Experimental Demonstration of Pulse <span class="hlt">Wave</span> <span class="hlt">Propagation</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Stojadinovic, Bojana; Nestorovic, Zorica; Djuric, Biljana; Tenne, Tamar; Zikich, Dragoslav; Žikic, Dejan</p> <p>2017-01-01</p> <p>The velocity by which a disturbance moves through the medium is the <span class="hlt">wave</span> velocity. Pulse <span class="hlt">wave</span> velocity is among the key parameters in hemodynamics. Investigation of <span class="hlt">wave</span> <span class="hlt">propagation</span> through the fluid-filled elastic tube has a great importance for the proper biophysical understanding of the nature of blood flow through the cardiovascular system.…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH43B1846G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH43B1846G"><span><span class="hlt">Tsunami</span> hazard assessment at Port Alberni, BC, Canada: preliminary model results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grilli, S. T.; Insua, T. L.; Grilli, A. R.; Douglas, K. L.; Shelby, M. R.; Wang, K.; Gao, D.</p> <p>2016-12-01</p> <p>Located in the heart of Vancouver Island, BC, Port Alberni has a well-known history of <span class="hlt">tsunamis</span>. Many of the Nuu-Chah-Nulth First Nations share oral stories about a strong fight between a thunderbird and a whale that caused big <span class="hlt">waves</span> in a winter night, a story that is compatible with the recently recognized great Cascadia <span class="hlt">tsunami</span> in January, 1700. Port Alberni, with a total population of approximately 20,000 people, lies beside the Somass River, at the very end of Barkley Sound Inlet. The narrow canal connecting this town to the Pacific Ocean runs for more than 64 km ( 40 miles) between steep mountains, providing an ideal setting for the amplification of <span class="hlt">tsunami</span> <span class="hlt">waves</span> through funnelling effects. The devastating effects of <span class="hlt">tsunamis</span> are still fresh in residents' memories from the impact of the 1964 Alaska <span class="hlt">tsunami</span> that caused serious damage to the city. In June 2016, Emergency Management BC ran a coastal exercise in Port Alberni, simulating the response to an earthquake and a <span class="hlt">tsunami</span>. During three days, the emergency teams in the City of Port Alberni practiced and learned from the experience. Ocean Networks Canada contributed to this exercise with the development of preliminary simulations of <span class="hlt">tsunami</span> impact on the city from a buried rupture of the Cascadia Subduction Zone, including the Explorer segment. <span class="hlt">Wave</span> <span class="hlt">propagation</span> was simulated with the long-<span class="hlt">wave</span> model FUNWAVE-TVD. Preliminary results indicate a strong amplification of <span class="hlt">tsunami</span> <span class="hlt">waves</span> in the Port Alberni area. The inundation zone in Port Alberni had a footprint similar to that of the 1700 Cascadia and 1964 Alaska <span class="hlt">tsunamis</span>, inundating the area surrounding the Somass river and preferentially following the Kitsuksis and Roger Creek river margins into the city. Several other <span class="hlt">tsunami</span> source scenarios, including splay faulting and trench-breaching ruptures are currently being modeled for the city of Port Alberni following a similar approach. These results will be presented at the conference.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhRvE..97b2209W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhRvE..97b2209W"><span>Metastable modular metastructures for on-demand reconfiguration of band structures and nonreciprocal <span class="hlt">wave</span> <span class="hlt">propagation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Z.; Zheng, Y.; Wang, K. W.</p> <p>2018-02-01</p> <p>We present an approach to achieve adaptable band structures and nonreciprocal <span class="hlt">wave</span> <span class="hlt">propagation</span> by exploring and exploiting the concept of metastable modular metastructures. Through studying the dynamics of <span class="hlt">wave</span> <span class="hlt">propagation</span> in a chain composed of finite metastable modules, we provide experimental and analytical results on nonreciprocal <span class="hlt">wave</span> <span class="hlt">propagation</span> and unveil the underlying mechanisms that facilitate such unidirectional energy transmission. In addition, we demonstrate that via transitioning among the numerous metastable states, the proposed metastructure is endowed with a large number of bandgap reconfiguration possibilities. As a result, we illustrate that unprecedented adaptable nonreciprocal <span class="hlt">wave</span> <span class="hlt">propagation</span> can be realized using the metastable modular metastructure. Overall, this research elucidates the rich dynamics attainable through the combinations of periodicity, nonlinearity, spatial asymmetry, and metastability and creates a class of adaptive structural and material systems capable of realizing tunable bandgaps and nonreciprocal <span class="hlt">wave</span> transmissions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IJT....37..101G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IJT....37..101G"><span>Laser-Generated Rayleigh <span class="hlt">Waves</span> <span class="hlt">Propagating</span> in Transparent Viscoelastic Adhesive Coating/Metal Substrate Systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guan, Yi-jun; Sun, Hong-xiang; Yuan, Shou-qi; Zhang, Shu-yi; Ge, Yong</p> <p>2016-10-01</p> <p>We have established numerical models for simulating laser-generated Rayleigh <span class="hlt">waves</span> in coating/substrate systems by a finite element method and investigated the <span class="hlt">propagation</span> characteristics of Rayleigh <span class="hlt">waves</span> in systems concerning the viscoelasticity and transparency of adhesive coatings. In this way, we have studied the influence of the mechanical properties of the coating, such as the elastic moduli, viscoelastic moduli, coating thickness, transparency, and coating material, on the <span class="hlt">propagation</span> characteristics of the Rayleigh <span class="hlt">waves</span>. The results show that the <span class="hlt">propagation</span> characteristics of the Rayleigh <span class="hlt">waves</span> can be divided into low- and high-frequency parts. The high-frequency <span class="hlt">propagation</span> characteristics of the Rayleigh <span class="hlt">wave</span> are closely related to the properties of the adhesive coating.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15620512','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15620512"><span>Control of <span class="hlt">wave</span> <span class="hlt">propagation</span> in a biological excitable medium by an external electric field.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sebestikova, Lenka; Slamova, Elena; Sevcikova, Hana</p> <p>2005-03-01</p> <p>We present an experimental evidence of effects of external electric fields (EFs) on the velocity of pulse <span class="hlt">waves</span> <span class="hlt">propagating</span> in a biological excitable medium. The excitable medium used is formed by a layer of starving cells of Dictyostelium discoideum through which the <span class="hlt">waves</span> of increased concentration of cAMP <span class="hlt">propagate</span> by reaction-diffusion mechanism. External dc EFs of low intensities (up to 5 V/cm) are shown to speed up the <span class="hlt">propagation</span> of cAMP <span class="hlt">waves</span> towards the positive electrode and slow it down towards the negative electrode. Electric fields were also found to support an emergence of new centers, emitting cAMP <span class="hlt">waves</span>, in front of cAMP <span class="hlt">waves</span> <span class="hlt">propagating</span> towards the negative electrode.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1511690K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1511690K"><span>GPS-TEC of the Ionospheric Disturbances as a Tool for Early <span class="hlt">Tsunami</span> Warning</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kunitsyn, Viacheslav E.; Nesterov, Ivan A.; Shalimov, Sergey L.; Krysanov, Boris Yu.; Padokhin, Artem M.; Rekenthaler, Douglas</p> <p>2013-04-01</p> <p>Recently, the GPS measurements were used for retrieving the information on the various types of ionospheric responses to seismic events (earthquakes, seismic Rayleigh <span class="hlt">waves</span>, and <span class="hlt">tsunami</span>) which generate atmospheric <span class="hlt">waves</span> <span class="hlt">propagating</span> up to the ionospheric altitudes where the collisions between the neutrals and charge particles give rise to the motion of the ionospheric plasma. These experimental results can well be used in architecture of the future <span class="hlt">tsunami</span> warning system. The point is an earlier (in comparison with seismological methods) detection of the ionospheric signal that can indicate the moment of <span class="hlt">tsunami</span> generation. As an example we consider the two-dimensional distributions of the vertical total electron content (TEC) variations in the ionosphere both close to and far from the epicenter of the Japan undersea earthquake of March 11, 2011 using radio tomographic (RT) reconstruction of high-temporal-resolution (2-minute) data from the Japan and the US GPS networks. Near-zone TEC variations shows a diverging ionospheric perturbation with multi-component spectral composition emerging after the main shock. The initial phase of the disturbance can be used as an indicator of the <span class="hlt">tsunami</span> generation and subsequently for the <span class="hlt">tsunami</span> early warning. Far-zone TEC variations reveals distinct <span class="hlt">wave</span> train associated with gravity <span class="hlt">waves</span> generated by <span class="hlt">tsunami</span>. According to observations <span class="hlt">tsunami</span> arrives at Hawaii and further at the coast of Southern California with delay relative to the gravity <span class="hlt">waves</span>. Therefore the gravity <span class="hlt">wave</span> pattern can be used in the early <span class="hlt">tsunami</span> warning. We support this scenario by the results of modeling with the parameters of the ocean surface perturbation corresponding to the considered earthquake. In addition it was observed in the modeling that at long distance from the source the gravity <span class="hlt">wave</span> can pass ahead of the <span class="hlt">tsunami</span>. The work was supported by the Russian Foundation for Basic Research (grants 11-05-01157 and 12-05-33065).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4015334','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4015334"><span>The stimulus-evoked population response in visual cortex of awake monkey is a <span class="hlt">propagating</span> <span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Muller, Lyle; Reynaud, Alexandre; Chavane, Frédéric; Destexhe, Alain</p> <p>2014-01-01</p> <p><span class="hlt">Propagating</span> <span class="hlt">waves</span> occur in many excitable media and were recently found in neural systems from retina to neocortex. While <span class="hlt">propagating</span> <span class="hlt">waves</span> are clearly present under anaesthesia, whether they also appear during awake and conscious states remains unclear. One possibility is that these <span class="hlt">waves</span> are systematically missed in trial-averaged data, due to variability. Here we present a method for detecting <span class="hlt">propagating</span> <span class="hlt">waves</span> in noisy multichannel recordings. Applying this method to single-trial voltage-sensitive dye imaging data, we show that the stimulus-evoked population response in primary visual cortex of the awake monkey <span class="hlt">propagates</span> as a travelling <span class="hlt">wave</span>, with consistent dynamics across trials. A network model suggests that this reliability is the hallmark of the horizontal fibre network of superficial cortical layers. <span class="hlt">Propagating</span> <span class="hlt">waves</span> with similar properties occur independently in secondary visual cortex, but maintain precise phase relations with the <span class="hlt">waves</span> in primary visual cortex. These results show that, in response to a visual stimulus, <span class="hlt">propagating</span> <span class="hlt">waves</span> are systematically evoked in several visual areas, generating a consistent spatiotemporal frame for further neuronal interactions. PMID:24770473</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoJI.tmp..184C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoJI.tmp..184C"><span>Influence of off-great-circle <span class="hlt">propagation</span> of Rayleigh <span class="hlt">waves</span> on event-based surface <span class="hlt">wave</span> tomography in Northeast China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Haopeng; Ni, Sidao; Chu, Risheng; Chong, Jiajun; Liu, Zhikun; Zhu, Liangbao</p> <p>2018-05-01</p> <p>Surface <span class="hlt">waves</span> are generally assumed to <span class="hlt">propagate</span> along great-circle paths in most surface-<span class="hlt">wave</span> tomography. However, when lateral heterogeneity is strong, off-great-circle <span class="hlt">propagation</span> may occur and deteriorate surface <span class="hlt">wave</span> tomography results based on the great-circle assumption. In this study, we used teleseismic waveforms recorded by the NECESSArray in Northeast China to study off-great-circle <span class="hlt">propagation</span> of Rayleigh <span class="hlt">waves</span> using the beamforming method and evaluated the influence of off-great-circle <span class="hlt">propagation</span> on event-based surface <span class="hlt">wave</span> tomography. The results show that arrival angle anomalies generally increase with decreasing period. The arrival angle anomalies at 60 and 50 s periods are smaller than that at 40 and 30 s periods, which indicates that the off-great-circle <span class="hlt">propagation</span> is relatively weak for longer periods. At 30 s period, the arrival angle anomalies are relatively larger and some of the measurements can exceed 20°, which represents a strong off-great-circle <span class="hlt">propagation</span> effect. In some areas, the arrival angle anomalies of adjacent events differ significantly, which may be attributed to multipathing <span class="hlt">propagation</span> of surface <span class="hlt">waves</span>. To evaluate the influence of off-great-circle <span class="hlt">propagation</span> on event-based surface <span class="hlt">wave</span> tomography, we used measured arrival angle anomalies to correct two-station phase velocity measurements, and performed azimuthal anisotropy tomography using dispersion datasets with and without the arrival angle correction. At longer periods, such as 60 s, the influence of off-great-circle <span class="hlt">propagation</span> on surface <span class="hlt">wave</span> tomography is weak even though the corrected model has better data fit than the uncorrected model. However, the influence of off-great-circle <span class="hlt">propagation</span> is non-negligible at short periods. The tomography results at 30 s period show that the differences in phase velocity, the strength of anisotropy and the fast direction can be as large as 1.5 per cent, 1.0 per cent and 30°, respectively. Furthermore, the corrected phase</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5636206','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5636206"><span><span class="hlt">Tsunamis</span> in the geological record: Making <span class="hlt">waves</span> with a cautionary tale from the Mediterranean</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Marriner, Nick; Kaniewski, David; Morhange, Christophe; Flaux, Clément; Giaime, Matthieu; Vacchi, Matteo; Goff, James</p> <p>2017-01-01</p> <p>From 2000 to 2015, <span class="hlt">tsunamis</span> and storms killed more than 430,000 people worldwide and affected a further >530 million, with total damages exceeding US$970 billion. These alarming trends, underscored by the tragic events of the 2004 Indian Ocean catastrophe, have fueled increased worldwide demands for assessments of past, present, and future coastal risks. Nonetheless, despite its importance for hazard mitigation, discriminating between storm and <span class="hlt">tsunami</span> deposits in the geological record is one of the most challenging and hotly contended topics in coastal geoscience. To probe this knowledge gap, we present a 4500-year reconstruction of “tsunami” variability from the Mediterranean based on stratigraphic but not historical archives and assess it in relation to climate records and reconstructions of storminess. We elucidate evidence for previously unrecognized “<span class="hlt">tsunami</span> megacycles” with three peaks centered on the Little Ice Age, 1600, and 3100 cal. yr B.P. (calibrated years before present). These ~1500-year cycles, strongly correlated with climate deterioration in the Mediterranean/North Atlantic, challenge up to 90% of the original <span class="hlt">tsunami</span> attributions and suggest, by contrast, that most events are better ascribed to periods of heightened storminess. This timely and provocative finding is crucial in providing appropriately tailored assessments of coastal hazard risk in the Mediterranean and beyond. PMID:29026879</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S21A4388R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S21A4388R"><span>New Perspective of <span class="hlt">Tsunami</span> Deposit Investigations: Insight from the 1755 Lisbon <span class="hlt">Tsunami</span> in Martinique, Lesser Antilles.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Roger, J.; Clouard, V.; Moizan, E.</p> <p>2014-12-01</p> <p>The recent devastating <span class="hlt">tsunamis</span> having occurred during the last decades have highlighted the essential necessity to deploy operationnal warning systems and educate coastal populations. This could not be prepared correctly without a minimum knowledge about the <span class="hlt">tsunami</span> history. That is the case of the Lesser Antilles islands, where a few handfuls of <span class="hlt">tsunamis</span> have been reported over the past 5 centuries, some of them leading to notable destructions and inundations. But the lack of accurate details for most of the historical <span class="hlt">tsunamis</span> and the limited period during which we could find written information represents an important problem for <span class="hlt">tsunami</span> hazard assessment in this region. Thus, it is of major necessity to try to find other evidences of past <span class="hlt">tsunamis</span> by looking for sedimentary deposits. Unfortunately, island tropical environments do not seem to be the best places to keep such deposits burried. In fact, heavy rainfalls, storms, and all other phenomena leading to coastal erosion, and associated to human activities such as intensive sugarcane cultivation in coastal flat lands, could caused the loss of potential <span class="hlt">tsunami</span> deposits. Lots of places have been accurately investigated within the Lesser Antilles (from Sainte-Lucia to the British Virgin Islands) the last 3 years and nothing convincing has been found. That is when archeaological investigations excavated a 8-cm thick sandy and shelly layer in downtown Fort-de-France (Martinique), wedged between two well-identified layers of human origin (Fig. 1), that we found new hope: this sandy layer has been quickly attributed without any doubt to the 1755 <span class="hlt">tsunami</span>, using on one hand the information provided by historical reports of the construction sites, and on the other hand by numerical modeling of the <span class="hlt">tsunami</span> (<span class="hlt">wave</span> heights, velocity fields, etc.) showing the ability of this transoceanic <span class="hlt">tsunami</span> to wrap around the island after ~7 hours of <span class="hlt">propagation</span>, enter Fort-de-France's Bay with enough energy to carry sediments, and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1611137L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1611137L"><span><span class="hlt">Tsunami</span> Ionospheric warning and Ionospheric seismology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lognonne, Philippe; Rolland, Lucie; Rakoto, Virgile; Coisson, Pierdavide; Occhipinti, Giovanni; Larmat, Carene; Walwer, Damien; Astafyeva, Elvira; Hebert, Helene; Okal, Emile; Makela, Jonathan</p> <p>2014-05-01</p> <p>The last decade demonstrated that seismic <span class="hlt">waves</span> and <span class="hlt">tsunamis</span> are coupled to the ionosphere. Observations of Total Electron Content (TEC) and airglow perturbations of unique quality and amplitude were made during the Tohoku, 2011 giant Japan quake, and observations of much lower <span class="hlt">tsunamis</span> down to a few cm in sea uplift are now routinely done, including for the Kuril 2006, Samoa 2009, Chili 2010, Haida Gwai 2012 <span class="hlt">tsunamis</span>. This new branch of seismology is now mature enough to tackle the new challenge associated to the inversion of these data, with either the goal to provide from these data maps or profile of the earth surface vertical displacement (and therefore crucial information for <span class="hlt">tsunami</span> warning system) or inversion, with ground and ionospheric data set, of the various parameters (atmospheric sound speed, viscosity, collision frequencies) controlling the coupling between the surface, lower atmosphere and the ionosphere. We first present the state of the art in the modeling of the <span class="hlt">tsunami</span>-atmospheric coupling, including in terms of slight perturbation in the <span class="hlt">tsunami</span> phase and group velocity and dependance of the coupling strength with local time, ocean depth and season. We then show the confrontation of modelled signals with observations. For <span class="hlt">tsunami</span>, this is made with the different type of measurement having proven ionospheric <span class="hlt">tsunami</span> detection over the last 5 years (ground and space GPS, Airglow), while we focus on GPS and GOCE observation for seismic <span class="hlt">waves</span>. These observation systems allowed to track the <span class="hlt">propagation</span> of the signal from the ground (with GPS and seismometers) to the neutral atmosphere (with infrasound sensors and GOCE drag measurement) to the ionosphere (with GPS TEC and airglow among other ionospheric sounding techniques). Modelling with different techniques (normal modes, spectral element methods, finite differences) are used and shown. While the fits of the waveform are generally very good, we analyse the differences and draw direction of future</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/207837-fdtd-simulation-em-wave-propagation-media','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/207837-fdtd-simulation-em-wave-propagation-media"><span>FDTD simulation of EM <span class="hlt">wave</span> <span class="hlt">propagation</span> in 3-D media</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang, T.; Tripp, A.C.</p> <p>1996-01-01</p> <p>A finite-difference, time-domain solution to Maxwell`s equations has been developed for simulating electromagnetic <span class="hlt">wave</span> <span class="hlt">propagation</span> in 3-D media. The algorithm allows arbitrary electrical conductivity and permittivity variations within a model. The staggered grid technique of Yee is used to sample the fields. A new optimized second-order difference scheme is designed to approximate the spatial derivatives. Like the conventional fourth-order difference scheme, the optimized second-order scheme needs four discrete values to calculate a single derivative. However, the optimized scheme is accurate over a wider wavenumber range. Compared to the fourth-order scheme, the optimized scheme imposes stricter limitations on the time stepmore » sizes but allows coarser grids. The net effect is that the optimized scheme is more efficient in terms of computation time and memory requirement than the fourth-order scheme. The temporal derivatives are approximated by second-order central differences throughout. The Liao transmitting boundary conditions are used to truncate an open problem. A reflection coefficient analysis shows that this transmitting boundary condition works very well. However, it is subject to instability. A method that can be easily implemented is proposed to stabilize the boundary condition. The finite-difference solution is compared to closed-form solutions for conducting and nonconducting whole spaces and to an integral-equation solution for a 3-D body in a homogeneous half-space. In all cases, the finite-difference solutions are in good agreement with the other solutions. Finally, the use of the algorithm is demonstrated with a 3-D model. Numerical results show that both the magnetic field response and electric field response can be useful for shallow-depth and small-scale investigations.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eosweb.larc.nasa.gov/project/misr/gallery/tsunami_sri_lanka','SCIGOV-ASDC'); return false;" href="https://eosweb.larc.nasa.gov/project/misr/gallery/tsunami_sri_lanka"><span><span class="hlt">Tsunami</span>: Sri Lanka</span></a></p> <p><a target="_blank" href="http://eosweb.larc.nasa.gov/">Atmospheric Science Data Center </a></p> <p></p> <p>2013-04-16</p> <p>...     View Larger Image The initial <span class="hlt">tsunami</span> <span class="hlt">waves</span> resulting from the undersea earthquake ... ITSS/Jet Propulsion Laboratory); Michael Garay and David J. Diner (Jet Propulsion Laboratory, California Institute of Technology); and ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JaJAP..54gHF02M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JaJAP..54gHF02M"><span>Two-<span class="hlt">wave</span> <span class="hlt">propagation</span> in in vitro swine distal ulna</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mano, Isao; Horii, Kaoru; Matsukawa, Mami; Otani, Takahiko</p> <p>2015-07-01</p> <p>Ultrasonic transmitted <span class="hlt">waves</span> were obtained in an in vitro swine distal ulna specimen, which mimics a human distal radius, that consists of interconnected cortical bone and cancellous bone. The transmitted waveforms appeared similar to the fast <span class="hlt">waves</span>, slow <span class="hlt">waves</span>, and overlapping fast and slow <span class="hlt">waves</span> measured in the specimen after removing the surface cortical bone (only cancellous bone). In addition, the circumferential <span class="hlt">waves</span> in the cortical bone and water did not affect the fast and slow <span class="hlt">waves</span>. This suggests that the fast-and-slow-<span class="hlt">wave</span> phenomenon can be observed in an in vivo human distal radius.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19297001','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19297001"><span><span class="hlt">Propagation</span> of thickness-twist <span class="hlt">waves</span> in a piezoelectric ceramic plate with unattached electrodes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Qian, Zheng-Hua; Kishimoto, Kikuo; Yang, Jiashi</p> <p>2009-06-01</p> <p>We analyze the <span class="hlt">propagation</span> of thickness-twist <span class="hlt">waves</span> in an unbounded piezoelectric ceramic plate with air gaps between the plate surfaces and two electrodes. These <span class="hlt">waves</span> are also called anti-plane or shear-horizontal <span class="hlt">waves</span> with one displacement component only. An exact solution is obtained from the equations of the linear theory of piezoelectricity. Dispersion relations of the <span class="hlt">waves</span> are obtained and plotted. Results show that the <span class="hlt">wave</span> frequency or speed is sensitive to the air gap thickness. This effect can be used to manipulate the behavior of the <span class="hlt">waves</span> and has implications in acoustic <span class="hlt">wave</span> devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013NHESS..13.1795T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013NHESS..13.1795T"><span>The UBO-TSUFD <span class="hlt">tsunami</span> inundation model: validation and application to a <span class="hlt">tsunami</span> case study focused on the city of Catania, Italy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tinti, S.; Tonini, R.</p> <p>2013-07-01</p> <p>Nowadays numerical models are a powerful tool in <span class="hlt">tsunami</span> research since they can be used (i) to reconstruct modern and historical events, (ii) to cast new light on <span class="hlt">tsunami</span> sources by inverting <span class="hlt">tsunami</span> data and observations, (iii) to build scenarios in the frame of <span class="hlt">tsunami</span> mitigation plans, and (iv) to produce forecasts of <span class="hlt">tsunami</span> impact and inundation in systems of early warning. In parallel with the general recognition of the importance of numerical <span class="hlt">tsunami</span> simulations, the demand has grown for reliable <span class="hlt">tsunami</span> codes, validated through tests agreed upon by the <span class="hlt">tsunami</span> community. This paper presents the <span class="hlt">tsunami</span> code UBO-TSUFD that has been developed at the University of Bologna, Italy, and that solves the non-linear shallow water (NSW) equations in a Cartesian frame, with inclusion of bottom friction and exclusion of the Coriolis force, by means of a leapfrog (LF) finite-difference scheme on a staggered grid and that accounts for moving boundaries to compute sea inundation and withdrawal at the coast. Results of UBO-TSUFD applied to four classical benchmark problems are shown: two benchmarks are based on analytical solutions, one on a plane <span class="hlt">wave</span> <span class="hlt">propagating</span> on a flat channel with a constant slope beach; and one on a laboratory experiment. The code is proven to perform very satisfactorily since it reproduces quite well the benchmark theoretical and experimental data. Further, the code is applied to a realistic <span class="hlt">tsunami</span> case: a scenario of a <span class="hlt">tsunami</span> threatening the coasts of eastern Sicily, Italy, is defined and discussed based on the historical <span class="hlt">tsunami</span> of 11 January 1693, i.e. one of the most severe events in the Italian history.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1985JGR....90.1473T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1985JGR....90.1473T"><span>Azimuthal <span class="hlt">propagation</span> and frequency characteristic of compressional Pc 5 <span class="hlt">waves</span> observed at geostationary orbit</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takahashi, K.; Higbie, P. R.; Baker, D. N.</p> <p>1985-02-01</p> <p>Properties of compressional Pc 5 <span class="hlt">waves</span> as deduced from multiple-satellite observations at geosynchronous orbit are presented. The occurrence characteristics of the <span class="hlt">waves</span> are determined, and the relation between variations in particle fluxes and magnetic field is examined. The spatiotemporal structure of the <span class="hlt">waves</span> is considered, including the <span class="hlt">propagation</span> perpendicular to the ambient magnetic field and the relation of the frequency characteristics to harmonic <span class="hlt">waves</span>. It is demonstrated that the <span class="hlt">waves</span> have large azimuthal <span class="hlt">wave</span> numbers from 40 to 120, westward <span class="hlt">propagation</span> at a typical velocity of 10 km/s, frequency roughly 25 percent of the second harmonic of the poloidal <span class="hlt">wave</span>, and phase lag of 180 deg between the parallel and radial components of the <span class="hlt">wave</span> magnetic field and + or -90 deg between the parallel and azimuthal components. These features are discussed in the light of existing theories of instabilities in the ring current plasma.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22308064-post-fukushima-tsunami-simulations-malaysian-coasts','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22308064-post-fukushima-tsunami-simulations-malaysian-coasts"><span>Post Fukushima <span class="hlt">tsunami</span> simulations for Malaysian coasts</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Koh, Hock Lye, E-mail: kohhl@ucsiuniversity.edu.my; Teh, Su Yean, E-mail: syteh@usm.my; Abas, Mohd Rosaidi Che</p> <p></p> <p>The recent recurrences of mega <span class="hlt">tsunamis</span> in the Asian region have rekindled concern regarding potential <span class="hlt">tsunamis</span> that could inflict severe damage to affected coastal facilities and communities. The 11 March 2011 Fukushima <span class="hlt">tsunami</span> that crippled nuclear power plants in Northern Japan has further raised the level of caution. The recent discovery of petroleum reserves in the coastal water surrounding Malaysia further ignites the concern regarding <span class="hlt">tsunami</span> hazards to petroleum facilities located along affected coasts. Working in a group, federal government agencies seek to understand the dynamics of <span class="hlt">tsunami</span> and their impacts under the coordination of the Malaysian National Centre formore » <span class="hlt">Tsunami</span> Research, Malaysian Meteorological Department. Knowledge regarding the generation, <span class="hlt">propagation</span> and runup of <span class="hlt">tsunami</span> would provide the scientific basis to address safety issues. An in-house <span class="hlt">tsunami</span> simulation models known as TUNA has been developed by the authors to assess <span class="hlt">tsunami</span> hazards along affected beaches so that mitigation measures could be put in place. Capacity building on <span class="hlt">tsunami</span> simulation plays a critical role in the development of <span class="hlt">tsunami</span> resilience. This paper aims to first provide a simple introduction to <span class="hlt">tsunami</span> simulation towards the achievement of <span class="hlt">tsunami</span> simulation capacity building. The paper will also present several scenarios of <span class="hlt">tsunami</span> dangers along affected Malaysia coastal regions via TUNA simulations to highlight <span class="hlt">tsunami</span> threats. The choice of <span class="hlt">tsunami</span> generation parameters reflects the concern following the Fukushima <span class="hlt">tsunami</span>.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1916564R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1916564R"><span>Inversion of the perturbation GPS-TEC data induced by <span class="hlt">tsunamis</span> in order to estimate the sea level anomaly.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rakoto, Virgile; Lognonné, Philippe; Rolland, Lucie; Coïsson, Pierdavide; Drilleau, Mélanie</p> <p>2017-04-01</p> <p>Large underwater earthquakes (Mw > 7) can transmit part of their energy to the surrounding ocean through large sea-floor motions, generating <span class="hlt">tsunamis</span> that <span class="hlt">propagate</span> over long distances. The forcing effect of <span class="hlt">tsunami</span> <span class="hlt">waves</span> on the atmosphere generate internal gravity <span class="hlt">waves</span> which produce detectable ionospheric perturbations when they reach the upper atmosphere. Theses perturbations are frequently observed in the total electron content (TEC) measured by the multi-frequency Global navigation Satellite systems (GNSS) data (e.g., GPS,GLONASS). In this paper, we performed for the first time an inversion of the sea level anomaly using the GPS TEC data using a least square inversion (LSQ) through a normal modes summation modeling technique. Using the <span class="hlt">tsunami</span> of the 2012 Haida Gwaii in far field as a test case, we showed that the amplitude peak to peak of the sea level anomaly inverted using this method is below 10 % error. Nevertheless, we cannot invert the second <span class="hlt">wave</span> arriving 20 minutes later. This second <span class="hlt">wave</span> is generaly explain by the coastal reflection which the normal modeling does not take into account. Our technique is then applied to two other <span class="hlt">tsunamis</span> : the 2006 Kuril Islands <span class="hlt">tsunami</span> in far field, and the 2011 Tohoku <span class="hlt">tsunami</span> in closer field. This demonstrates that the inversion using a normal mode approach is able to estimate fairly well the amplitude of the first arrivals of the <span class="hlt">tsunami</span>. In the future, we plan to invert in real the TEC data in order to retrieve the <span class="hlt">tsunami</span> height.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhPl...25a3707D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhPl...25a3707D"><span><span class="hlt">Propagation</span> characteristics of electromagnetic <span class="hlt">waves</span> in dusty plasma with full ionization</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dan, Li; Guo, Li-Xin; Li, Jiang-Ting</p> <p>2018-01-01</p> <p>This study investigates the <span class="hlt">propagation</span> characteristics of electromagnetic (EM) <span class="hlt">waves</span> in fully ionized dusty plasmas. The <span class="hlt">propagation</span> characteristics of fully ionized plasma with and without dust under the Fokker-Planck-Landau (FPL) and Bhatnagar-Gross-Krook (BGK) models are compared to those of weakly ionized plasmas by using the <span class="hlt">propagation</span> matrix method. It is shown that the FPL model is suitable for the analysis of the <span class="hlt">propagation</span> characteristics of weakly collisional and fully ionized dusty plasmas, as is the BGK model. The influence of varying the dust parameters on the <span class="hlt">propagation</span> properties of EM <span class="hlt">waves</span> in the fully ionized dusty plasma was analyzed using the FPL model. The simulation results indicated that the densities and average radii of dust grains influence the reflection and transmission coefficients of fully ionized dusty plasma slabs. These results may be utilized to analyze the effects of interaction between EM <span class="hlt">waves</span> and dusty plasmas, such as those associated with hypersonic vehicles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170005214','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170005214"><span>Asteroid Generated <span class="hlt">Tsunami</span> Workshop: Summary of NASA/NOAA Workshop</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Morrison, David; Venkatapathy, Ethiraj</p> <p>2017-01-01</p> <p>A two-day workshop on <span class="hlt">tsunami</span> generated by asteroid impacts in the ocean resulted in a broad consensus that the asteroid impact <span class="hlt">tsunami</span> threat is not as great as previously thought, that airburst events in particular are unlikely to produce significant damage by <span class="hlt">tsunami</span>, and that the <span class="hlt">tsunami</span> contribution to the global ensemble impact hazard is substantially less than the contribution from land impacts. The workshop, led by Ethiraj Venkatapathy and David Morrison of NASA Ames, was organized into three sessions: 1) Near-field <span class="hlt">wave</span> generation by the impact; 2) Long distance <span class="hlt">wave</span> <span class="hlt">propagation</span>; 3) Damage from coastal run-up and inundation, and associated hazard. Workshop approaches were to compare simulations to understand differences in the results and gain confidence in the modeling for both formation and <span class="hlt">propagation</span> of <span class="hlt">tsunami</span> from asteroid impacts, and to use this information for preliminary global risk assessment. The workshop focus was on smaller asteroids (diameter less than 250m), which represent the most frequent impacts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRD..12211301X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRD..12211301X"><span>Impacts of Horizontal <span class="hlt">Propagation</span> of Orographic Gravity <span class="hlt">Waves</span> on the <span class="hlt">Wave</span> Drag in the Stratosphere and Lower Mesosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, Xin; Wang, Yuan; Xue, Ming; Zhu, Kefeng</p> <p>2017-11-01</p> <p>The impact of horizontal <span class="hlt">propagation</span> of mountain <span class="hlt">waves</span> on the orographic gravity <span class="hlt">wave</span> drag (OGWD) in the stratosphere and lower mesosphere of the Northern Hemisphere is evaluated for the first time. Using a fine-resolution (1 arc min) terrain and 2.5°×2.5° European Centre for Medium-Range Weather Forecasts ERA-Interim reanalysis data during 2011-2016, two sets of OGWD are calculated offline according to a traditional parameterization scheme (without horizontal <span class="hlt">propagation</span>) and a newly proposed scheme (with horizontal <span class="hlt">propagation</span>). In both cases, the zonal mean OGWDs show similar spatial patterns and undergo a notable seasonal variation. In winter, the OGWD is mainly distributed in the upper stratosphere and lower mesosphere of middle to high latitudes, whereas the summertime OGWD is confined in the lower stratosphere. Comparison between the two sets of OGWD reveal that the horizontal <span class="hlt">propagation</span> of mountain <span class="hlt">waves</span> tends to decrease (increase) the OGWD in the lower stratosphere (middle to upper stratosphere and lower mesosphere). Consequently, including the horizontal <span class="hlt">propagation</span> of mountain <span class="hlt">waves</span> in the parameterization of OGWD can reduce the excessive OGWD in the lower stratosphere and strengthen the insufficient gravity <span class="hlt">wave</span> forcing in the mesosphere, which are the known problems of traditional OGWD schemes. The impact of horizontal <span class="hlt">propagation</span> is more prominent in winter than in summer, with the OGWD in western Tibetan Plateau, Rocky Mountains, and Greenland notably affected.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995PApGe.144..875I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995PApGe.144..875I"><span>Field survey of the 1994 Mindoro Island, Philippines <span class="hlt">tsunami</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Imamura, Fumihiko; Synolakis, Costas E.; Gica, Edison; Titov, Vasily; Listanco, Eddie; Lee, Ho Jun</p> <p>1995-09-01</p> <p>This is a report of the field survey of the November 15, 1994 Mindoro Island, Philippines, <span class="hlt">tsunami</span> generated by an earthquake ( M=7.0) with a strike-slip motion. We will report runup heights from 54 locations on Luzon, Mindoro and other smaller islands in the Cape Verde passage between Mindoro and Luzon. Most of the damage was concentrated along the northern coast of Mindoro. Runup height distribution ranged 3 4 m at the most severely damaged areas and 2 4 in neighboring areas. The <span class="hlt">tsunami</span>-affected area was limited to within 10 km of the epicenter. The largest recorded runup value of 7.3 m was measured on the southwestern coast of Baco Island while a runup of 6.1 m was detected on its northern coastline. The earthquake and <span class="hlt">tsunami</span> killed 62 people, injured 248 and destroyed 800 houses. As observed in other recent <span class="hlt">tsunami</span> disasters, most of the casualties were children. Nearly all eyewitnesses interviewed described the first <span class="hlt">wave</span> as a leading-depression <span class="hlt">wave</span>. Eyewitnesses reported that the main direction of <span class="hlt">tsunami</span> <span class="hlt">propagation</span> was SW in Subaang Bay, SE in Wawa and Calapan, NE on Baco Island and N on Verde Island, suggesting that the <span class="hlt">tsunami</span> source area was in the southern Pass of Verde Island and that the <span class="hlt">wave</span> <span class="hlt">propagated</span> rapidly in all directions. The fault plane extended offshore to the N of Mindoro Island, with its rupture originating S of Verde Island and <span class="hlt">propagating</span> almost directly south to the inland of Mindoro, thereby accounting for the relatively limited damage area observed on the N of Mindoro.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MS%26E..274a2128Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MS%26E..274a2128Z"><span>The numerical simulation of Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> in laser welding of stainless steel</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Bo; Liu, Fang; Liu, Chang; Li, Jingming; Zhang, Baojun; Zhou, Qingxiang; Han, Xiaohui; Zhao, Yang</p> <p>2017-12-01</p> <p>In order to explore the Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> in laser welding of stainless steel, the numerical simulation is used to show the feature of Lamb <span class="hlt">wave</span>. In this paper, according to Lamb dispersion equation, excites the Lamb <span class="hlt">wave</span> on the edge of thin stainless steel plate, and presents the reflection coefficient for quantizing the Lamb <span class="hlt">wave</span> energy, the results show that the reflection coefficient is increased with the welding width increasing,</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26093440','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26093440"><span>Elastic parabolic equation solutions for oceanic T-<span class="hlt">wave</span> generation and <span class="hlt">propagation</span> from deep seismic sources.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Frank, Scott D; Collis, Jon M; Odom, Robert I</p> <p>2015-06-01</p> <p>Oceanic T-<span class="hlt">waves</span> are earthquake signals that originate when elastic <span class="hlt">waves</span> interact with the fluid-elastic interface at the ocean bottom and are converted to acoustic <span class="hlt">waves</span> in the ocean. These <span class="hlt">waves</span> <span class="hlt">propagate</span> long distances in the Sound Fixing and Ranging (SOFAR) channel and tend to be the largest observed arrivals from seismic events. Thus, an understanding of their generation is important for event detection, localization, and source-type discrimination. Recently benchmarked seismic self-starting fields are used to generate elastic parabolic equation solutions that demonstrate generation and <span class="hlt">propagation</span> of oceanic T-<span class="hlt">waves</span> in range-dependent underwater acoustic environments. Both downward sloping and abyssal ocean range-dependent environments are considered, and results demonstrate conversion of elastic <span class="hlt">waves</span> into water-borne oceanic T-<span class="hlt">waves</span>. Examples demonstrating long-range broadband T-<span class="hlt">wave</span> <span class="hlt">propagation</span> in range-dependent environments are shown. These results confirm that elastic parabolic equation solutions are valuable for characterization of the relationships between T-<span class="hlt">wave</span> <span class="hlt">propagation</span> and variations in range-dependent bathymetry or elastic material parameters, as well as for modeling T-<span class="hlt">wave</span> receptions at hydrophone arrays or coastal receiving stations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22596760-numerical-experimental-study-lamb-wave-propagation-two-dimensional-acoustic-black-hole','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22596760-numerical-experimental-study-lamb-wave-propagation-two-dimensional-acoustic-black-hole"><span>Numerical and experimental study of Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> in a two-dimensional acoustic black hole</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Yan, Shiling; Shen, Zhonghua, E-mail: shenzh@njust.edu.cn; Lomonosov, Alexey M.</p> <p>2016-06-07</p> <p>The <span class="hlt">propagation</span> of laser-generated Lamb <span class="hlt">waves</span> in a two-dimensional acoustic black-hole structure was studied numerically and experimentally. The geometrical acoustic theory has been applied to calculate the beam trajectories in the region of the acoustic black hole. The finite element method was also used to study the time evolution of <span class="hlt">propagating</span> <span class="hlt">waves</span>. An optical system based on the laser-Doppler vibration method was assembled. The effect of the focusing <span class="hlt">wave</span> and the reduction in <span class="hlt">wave</span> speed of the acoustic black hole has been validated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoRL..42.4736M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoRL..42.4736M"><span>A new physics-based modeling approach for <span class="hlt">tsunami</span>-ionosphere coupling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meng, X.; Komjathy, A.; Verkhoglyadova, O. P.; Yang, Y.-M.; Deng, Y.; Mannucci, A. J.</p> <p>2015-06-01</p> <p><span class="hlt">Tsunamis</span> can generate gravity <span class="hlt">waves</span> <span class="hlt">propagating</span> upward through the atmosphere, inducing total electron content (TEC) disturbances in the ionosphere. To capture this process, we have implemented <span class="hlt">tsunami</span>-generated gravity <span class="hlt">waves</span> into the Global Ionosphere-Thermosphere Model (GITM) to construct a three-dimensional physics-based model WP (<span class="hlt">Wave</span> Perturbation)-GITM. WP-GITM takes <span class="hlt">tsunami</span> <span class="hlt">wave</span> properties, including the <span class="hlt">wave</span> height, <span class="hlt">wave</span> period, wavelength, and <span class="hlt">propagation</span> direction, as inputs and time-dependently characterizes the responses of the upper atmosphere between 100 km and 600 km altitudes. We apply WP-GITM to simulate the ionosphere above the West Coast of the United States around the time when the <span class="hlt">tsunami</span> associated with the March 2011 Tohuku-Oki earthquke arrived. The simulated TEC perturbations agree with Global Positioning System observations reasonably well. For the first time, a fully self-consistent and physics-based model has reproduced the GPS-observed traveling ionospheric signatures of an actual <span class="hlt">tsunami</span> event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PMB....57L...9R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PMB....57L...9R"><span>Counter-<span class="hlt">propagating</span> <span class="hlt">wave</span> interaction for contrast-enhanced ultrasound imaging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Renaud, G.; Bosch, J. G.; ten Kate, G. L.; Shamdasani, V.; Entrekin, R.; de Jong, N.; van der Steen, A. F. W.</p> <p>2012-11-01</p> <p>Most techniques for contrast-enhanced ultrasound imaging require linear <span class="hlt">propagation</span> to detect nonlinear scattering of contrast agent microbubbles. Waveform distortion due to nonlinear <span class="hlt">propagation</span> impairs their ability to distinguish microbubbles from tissue. As a result, tissue can be misclassified as microbubbles, and contrast agent concentration can be overestimated; therefore, these artifacts can significantly impair the quality of medical diagnoses. Contrary to biological tissue, lipid-coated gas microbubbles used as a contrast agent allow the interaction of two acoustic <span class="hlt">waves</span> <span class="hlt">propagating</span> in opposite directions (counter-<span class="hlt">propagation</span>). Based on that principle, we describe a strategy to detect microbubbles that is free from nonlinear <span class="hlt">propagation</span> artifacts. In vitro images were acquired with an ultrasound scanner in a phantom of tissue-mimicking material with a cavity containing a contrast agent. Unlike the default mode of the scanner using amplitude modulation to detect microbubbles, the pulse sequence exploiting counter-<span class="hlt">propagating</span> <span class="hlt">wave</span> interaction creates no pseudoenhancement behind the cavity in the contrast image.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1259966-conical-wave-propagation-diffraction-two-dimensional-hexagonally-packed-granular-lattices','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1259966-conical-wave-propagation-diffraction-two-dimensional-hexagonally-packed-granular-lattices"><span>Conical <span class="hlt">wave</span> <span class="hlt">propagation</span> and diffraction in two-dimensional hexagonally packed granular lattices</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Chong, C.; Kevrekidis, P. G.; Ablowitz, M. J.; ...</p> <p>2016-01-25</p> <p>We explore linear and nonlinear mechanisms for conical <span class="hlt">wave</span> <span class="hlt">propagation</span> in two-dimensional lattices in the realm of phononic crystals. As a prototypical example, a statically compressed granular lattice of spherical particles arranged in a hexagonal packing configuration is analyzed. Upon identifying the dispersion relation of the underlying linear problem, the resulting diffraction properties are considered. Analysis both via a heuristic argument for the linear <span class="hlt">propagation</span> of a <span class="hlt">wave</span> packet and via asymptotic analysis leading to the derivation of a Dirac system suggests the occurrence of conical diffraction. This analysis is valid for strong precompression, i.e., near the linear regime. Formore » weak precompression, conical <span class="hlt">wave</span> <span class="hlt">propagation</span> is still possible, but the resulting expanding circular <span class="hlt">wave</span> front is of a nonoscillatory nature, resulting from the complex interplay among the discreteness, nonlinearity, and geometry of the packing. Lastly, the transition between these two types of <span class="hlt">propagation</span> is explored.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2722927','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2722927"><span>Surface Current Density Mapping for Identification of Gastric Slow <span class="hlt">Wave</span> <span class="hlt">Propagation</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bradshaw, L. A.; Cheng, L. K.; Richards, W. O.; Pullan, A. J.</p> <p>2009-01-01</p> <p>The magnetogastrogram records clinically relevant parameters of the electrical slow <span class="hlt">wave</span> of the stomach noninvasively. Besides slow <span class="hlt">wave</span> frequency, gastric slow <span class="hlt">wave</span> <span class="hlt">propagation</span> velocity is a potentially useful clinical indicator of the state of health of gastric tissue, but it is a difficult parameter to determine from noninvasive bioelectric or biomagnetic measurements. We present a method for computing the surface current density (SCD) from multichannel magnetogastrogram recordings that allows computation of the <span class="hlt">propagation</span> velocity of the gastric slow <span class="hlt">wave</span>. A moving dipole source model with hypothetical as well as realistic biomagnetometer parameters demonstrates that while a relatively sparse array of magnetometer sensors is sufficient to compute a single average <span class="hlt">propagation</span> velocity, more detailed information about spatial variations in <span class="hlt">propagation</span> velocity requires higher density magnetometer arrays. Finally, the method is validated with simultaneous MGG and serosal EMG measurements in a porcine subject. PMID:19403355</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29047527','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29047527"><span>Invertible <span class="hlt">propagator</span> for plane <span class="hlt">wave</span> illumination of forward-scattering structures.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Samelsohn, Gregory</p> <p>2017-05-10</p> <p><span class="hlt">Propagation</span> of directed <span class="hlt">waves</span> in forward-scattering media is considered. It is assumed that the evolution of the <span class="hlt">wave</span> field is governed by the standard parabolic <span class="hlt">wave</span> equation. An efficient one-step momentum-space <span class="hlt">propagator</span>, suitable for a tilted plane <span class="hlt">wave</span> illumination of extended objects, is derived. It is expressed in terms of a <span class="hlt">propagation</span> operator that transforms (the complex exponential of) a linogram of the illuminated object into a set of its diffraction patterns. The invertibility of the <span class="hlt">propagator</span> is demonstrated, which permits a multiple-shot scatter correction to be performed, and makes the solution especially attractive for either projective or tomographic imaging. As an example, high-resolution tomograms are obtained in numerical simulations implemented for a synthetic phantom, with both refractive and absorptive inclusions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH23A1848V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH23A1848V"><span>Validation and Performance Comparison of Numerical Codes for <span class="hlt">Tsunami</span> Inundation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Velioglu, D.; Kian, R.; Yalciner, A. C.; Zaytsev, A.</p> <p>2015-12-01</p> <p>In inundation zones, <span class="hlt">tsunami</span> motion turns from <span class="hlt">wave</span> motion to flow of water. Modelling of this phenomenon is a complex problem since there are many parameters affecting the <span class="hlt">tsunami</span> flow. In this respect, the performance of numerical codes that analyze <span class="hlt">tsunami</span> inundation patterns becomes important. The computation of water surface elevation is not sufficient for proper analysis of <span class="hlt">tsunami</span> behaviour in shallow water zones and on land and hence for the development of mitigation strategies. Velocity and velocity patterns are also crucial parameters and have to be computed at the highest accuracy. There are numerous numerical codes to be used for simulating <span class="hlt">tsunami</span> inundation. In this study, FLOW 3D and NAMI DANCE codes are selected for validation and performance comparison. Flow 3D simulates linear and nonlinear <span class="hlt">propagating</span> surface <span class="hlt">waves</span> as well as long <span class="hlt">waves</span> by solving three-dimensional Navier-Stokes (3D-NS) equations. FLOW 3D is used specificaly for flood problems. NAMI DANCE uses finite difference computational method to solve linear and nonlinear forms of shallow water equations (NSWE) in long <span class="hlt">wave</span> problems, specifically <span class="hlt">tsunamis</span>. In this study, these codes are validated and their performances are compared using two benchmark problems which are discussed in 2015 National <span class="hlt">Tsunami</span> Hazard Mitigation Program (NTHMP) Annual meeting in Portland, USA. One of the problems is an experiment of a single long-period <span class="hlt">wave</span> <span class="hlt">propagating</span> up a piecewise linear slope and onto a small-scale model of the town of Seaside, Oregon. Other benchmark problem is an experiment of a single solitary <span class="hlt">wave</span> <span class="hlt">propagating</span> up a triangular shaped shelf with an island feature located at the offshore point of the shelf. The computed water surface elevation and velocity data are compared with the measured data. The comparisons showed that both codes are in fairly good agreement with each other and benchmark data. All results are presented with discussions and comparisons. The research leading to these</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/6419068-formation-propagation-love-waves-surface-layer-wave-source-technical-report','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/6419068-formation-propagation-love-waves-surface-layer-wave-source-technical-report"><span>Formation and <span class="hlt">propagation</span> of Love <span class="hlt">waves</span> in a surface layer with a P-<span class="hlt">wave</span> source. Technical report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Florence, A.L.; Miller, S.A.</p> <p></p> <p>The objective of this research is to investigate experimentally, and support with theoretical calculations, the formation and <span class="hlt">propagation</span> of Love <span class="hlt">waves</span> from a P-<span class="hlt">wave</span> source due to scattering at material heterogeneities. The P-<span class="hlt">wave</span> source is a spherical piezoelectric crystal cast in a surface layer of rock simulant overlaying a higher impedance granite substrate. Excitation of the piezoelectric crystal with a known voltage applies a spherical compressional pulse of known amplitude to the surrounding medium. Lateral heterogeneities cast in the surface layer convert incident P-<span class="hlt">wave</span> energy into shear <span class="hlt">waves</span>. The horizontally polarized shear <span class="hlt">waves</span> (SH <span class="hlt">waves</span>) trapped in the surface layermore » <span class="hlt">wave</span> guide are the Love <span class="hlt">waves</span> we will measure at the surface.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMPA43B2041B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMPA43B2041B"><span>Scientific Animations for <span class="hlt">Tsunami</span> Hazard Mitigation: The Pacific <span class="hlt">Tsunami</span> Warning Center's YouTube Channel</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Becker, N. C.; Wang, D.; Shiro, B.; Ward, B.</p> <p>2013-12-01</p> <p>Outreach and education save lives, and the Pacific <span class="hlt">Tsunami</span> Warning Center (PTWC) has a new tool--a YouTube Channel--to advance its mission to protect lives and property from dangerous <span class="hlt">tsunamis</span>. Such outreach and education is critical for coastal populations nearest an earthquake since they may not get an official warning before a <span class="hlt">tsunami</span> reaches them and will need to know what to do when they feel strong shaking. Those who live far enough away to receive useful official warnings and react to them, however, can also benefit from PTWC's education and outreach efforts. They can better understand a <span class="hlt">tsunami</span> warning message when they receive one, can better understand the danger facing them, and can better anticipate how events will unfold while the warning is in effect. The same holds true for emergency managers, who have the authority to evacuate the public they serve, and for the news media, critical partners in disseminating <span class="hlt">tsunami</span> hazard information. PTWC's YouTube channel supplements its formal outreach and education efforts by making its computer animations available 24/7 to anyone with an Internet connection. Though the YouTube channel is only a month old (as of August 2013), it should rapidly develop a large global audience since similar videos on PTWC's Facebook page have reached over 70,000 viewers during organized media events, while PTWC's official web page has received tens of millions of hits during damaging <span class="hlt">tsunamis</span>. These animations are not mere cartoons but use scientific data and calculations to render graphical depictions of real-world phenomena as accurately as possible. This practice holds true whether the animation is a simple comparison of historic earthquake magnitudes or a complex simulation cycling through thousands of high-resolution data grids to render <span class="hlt">tsunami</span> <span class="hlt">waves</span> <span class="hlt">propagating</span> across an entire ocean basin. PTWC's animations fall into two broad categories. The first group illustrates concepts about seismology and how it is critical to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170004626','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170004626"><span>Contribution of Asteroid Generated <span class="hlt">Tsunami</span> to the Impact Hazard</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Morrison, David; Venkatapathy, Ethiraj</p> <p>2017-01-01</p> <p>The long-standing uncertainty about the importance of asteroid-generated <span class="hlt">tsunami</span> was addressed at a workshop in August 2016, co-sponsored by NASA and NOAA. Experts from NASA, NOAA, the DoE tri-labs (LLNL, SNL, and LANL), DHS, FEMA, and academia addressed the hazard of <span class="hlt">tsunami</span> created by asteroid impacts, focusing primarily on NEAs with diameter less than 250m. Participants jointly identified key issues and shared information for nearly a year to coordinate their results for discussion at the workshop. They used modern computational tools to examine 1) Near-field <span class="hlt">wave</span> generation by the impact; 2) Long-distance <span class="hlt">wave</span> <span class="hlt">propagation</span>; 3) Damage from coastal run-up and inundation, and associated hazard. The workshop resulted in broad consensus that the asteroid impact <span class="hlt">tsunami</span> threat is not as great as previously thought.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://dx.doi.org/10.1016/S0065-2687(09)05108-5','USGSPUBS'); return false;" href="http://dx.doi.org/10.1016/S0065-2687(09)05108-5"><span>Chapter 3 – Phenomenology of <span class="hlt">Tsunamis</span>: Statistical Properties from Generation to Runup</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, Eric L.</p> <p>2015-01-01</p> <p>Observations related to <span class="hlt">tsunami</span> generation, <span class="hlt">propagation</span>, and runup are reviewed and described in a phenomenological framework. In the three coastal regimes considered (near-field broadside, near-field oblique, and far field), the observed maximum <span class="hlt">wave</span> amplitude is associated with different parts of the <span class="hlt">tsunami</span> wavefield. The maximum amplitude in the near-field broadside regime is most often associated with the direct arrival from the source, whereas in the near-field oblique regime, the maximum amplitude is most often associated with the <span class="hlt">propagation</span> of edge <span class="hlt">waves</span>. In the far field, the maximum amplitude is most often caused by the interaction of the <span class="hlt">tsunami</span> coda that develops during basin-wide <span class="hlt">propagation</span> and the nearshore response, including the excitation of edge <span class="hlt">waves</span>, shelf modes, and resonance. Statistical distributions that describe <span class="hlt">tsunami</span> observations are also reviewed, both in terms of spatial distributions, such as coseismic slip on the fault plane and near-field runup, and temporal distributions, such as <span class="hlt">wave</span> amplitudes in the far field. In each case, fundamental theories of <span class="hlt">tsunami</span> physics are heuristically used to explain the observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19750022814','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750022814"><span>Theoretical and experimental studies of space-related plasma <span class="hlt">wave</span> <span class="hlt">propagation</span> and resonance phenomena</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Crawford, F. W.</p> <p>1975-01-01</p> <p>A ten year summary was given of university research on the nature and characteristics of space related plasma resonance phenomena, whistler <span class="hlt">propagation</span> in laboratory plasmas, and theoretical and experimental studies of plasma <span class="hlt">wave</span> <span class="hlt">propagation</span>. Data are also given on long delayed echoes, low frequency instabilities, ionospheric heating, and backscatter, and pulse <span class="hlt">propagation</span>. A list is included of all conference papers, publications, and reports resulting from the study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21668440','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21668440"><span>Orthogonal <span class="hlt">wave</span> <span class="hlt">propagation</span> of epileptiform activity in the planar mouse hippocampus in vitro.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kibler, Andrew B; Durand, Dominique M</p> <p>2011-09-01</p> <p>In vitro brain preparations have been used extensively to study the generation and <span class="hlt">propagation</span> of epileptiform activity. Transverse and longitudinal slices of the rodent hippocampus have revealed various patterns of <span class="hlt">propagation</span>. Yet intact connections between the transverse and longitudinal pathways should generate orthogonal (both transverse and longitudinal) <span class="hlt">propagation</span> of seizures involving the entire hippocampus. This study utilizes the planar unfolded mouse hippocampus preparation to reveal simultaneous orthogonal epileptiform <span class="hlt">propagation</span> and to test a method of arresting <span class="hlt">propagation</span>. This study utilized an unfolded mouse hippocampus preparation. It was chosen due to its preservation of longitudinal neuronal processes, which are thought to play an important role in epileptiform hyperexcitability. 4-Aminopyridine (4-AP), microelectrodes, and voltage-sensitive dye imaging were employed to investigate tissue excitability. In 50-μm 4-AP, stimulation of the stratum radiatum induced transverse activation of CA3 cells but also induced a longitudinal <span class="hlt">wave</span> of activity <span class="hlt">propagating</span> along the CA3 region at a speed of 0.09 m/s. Without stimulation, a <span class="hlt">wave</span> originated at the temporal CA3 and <span class="hlt">propagated</span> in a temporal-septal direction could be suppressed with glutamatergic receptor antagonists. Orthogonal <span class="hlt">propagation</span> traveled longitudinally along the CA3 pathway, secondarily invading the CA1 region at a velocity of 0.22 ± 0.024 m/s. Moreover, a local lesion restricted to the CA3 region could arrest <span class="hlt">wave</span> <span class="hlt">propagation</span>. These results reveal a complex two-dimensional epileptiform <span class="hlt">wave</span> <span class="hlt">propagation</span> pattern in the hippocampus that is generated by a combination of synaptic transmission and axonal <span class="hlt">propagation</span> in the CA3 recurrent network. Epileptiform <span class="hlt">propagation</span> block via a transverse selective CA3 lesion suggests a potential surgical technique for the treatment of temporal lobe epilepsy. Wiley Periodicals, Inc. © 2011 International League Against Epilepsy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3169769','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3169769"><span>Orthogonal <span class="hlt">Wave</span> <span class="hlt">Propagation</span> of Epileptiform Activity in the Planar Mouse Hippocampus in vitro</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kibler, Andrew B; Durand, Dominique M</p> <p>2011-01-01</p> <p>Purpose In vitro brain preparations have been used extensively to study the generation and <span class="hlt">propagation</span> of epileptiform activity. Transverse and longitudinal slices of the rodent hippocampus have revealed various patterns of <span class="hlt">propagation</span>. Yet intact connections between the transverse and longitudinal pathways should generate orthogonal (both transverse and longitudinal) <span class="hlt">propagation</span> of seizures involving the entire hippocampus. This study utilizes the planar unfolded mouse hippocampus preparation to reveal simultaneous orthogonal epileptiform <span class="hlt">propagation</span> and to test a method of arresting <span class="hlt">propagation</span>. Methods This study utilized an unfolded mouse hippocampus preparation. It was chosen due to its preservation of longitudinal neuronal processes which are thought to play an important role in epileptiform hyper-excitability. 4-aminopyridine (4-AP), micro-electrodes, and voltage sensitive dye imaging were employed to investigate tissue excitability. Key Findings In 50 μM 4-AP, stimulation of the stratum radiatum induced transverse activation of CA3 cells but also induced a longitudinal <span class="hlt">wave</span> of activity <span class="hlt">propagating</span> along the CA3 region at a speed of 0.09 m/s. Without stimulation, a <span class="hlt">wave</span> originated at the temporal CA3 and <span class="hlt">propagated</span> in a temporal–septal direction and could be suppressed with glutamatergic antagonists. Orthogonal <span class="hlt">propagation</span> traveled longitudinally along the CA3 pathway, secondarily invading the CA1 region at a velocity of 0.22±0.024 m/s. Moreover, a local lesion restricted to the CA3 region could arrest <span class="hlt">wave</span> <span class="hlt">propagation</span>. Significance These results reveal a complex two-dimensional epileptiform <span class="hlt">wave</span> <span class="hlt">propagation</span> pattern in the hippocampus that is generated by a combination of synaptic transmission and axonal <span class="hlt">propagation</span> in the CA3 recurrent network. Epileptiform <span class="hlt">propagation</span> block via a transverse selective CA3 lesion suggests a potential surgical technique for the treatment of temporal lobe epilepsy. PMID:21668440</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA103878','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA103878"><span>Acceleration <span class="hlt">Wave</span> <span class="hlt">Propagation</span> in Hyperelastic Rods of Variable Cross-Section.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1981-07-01</p> <p>direction of <span class="hlt">propagation</span>. Many authors have considered both static and dynamic problems for such materials, of whom we mention only Antman [2] and... Antman and Jordan [3] who studied the Kirchhoff problem for nonlinearly elastic rods and qualitative properties in general, Jeffrey and Teymur [4] and...Jeffrey and Suhubi [5] who considered shock <span class="hlt">wave</span> formation and acceleration <span class="hlt">wave</span> <span class="hlt">propagation</span> through periodically layered media, and Antman and Liu [6</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AIPC.1650.1178K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AIPC.1650.1178K"><span>Numerical simulation and experimental validation of Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> behavior in composite plates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Sungwon; Uprety, Bibhisha; Mathews, V. John; Adams, Daniel O.</p> <p>2015-03-01</p> <p>Structural Health Monitoring (SHM) based on Acoustic Emission (AE) is dependent on both the sensors to detect an impact event as well as an algorithm to determine the impact location. The <span class="hlt">propagation</span> of Lamb <span class="hlt">waves</span> produced by an impact event in thin composite structures is affected by several unique aspects including material anisotropy, ply orientations, and geometric discontinuities within the structure. The development of accurate numerical models of Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> has important benefits towards the development of AE-based SHM systems for impact location estimation. Currently, many impact location algorithms utilize the time of arrival or velocities of Lamb <span class="hlt">waves</span>. Therefore the numerical prediction of characteristic <span class="hlt">wave</span> velocities is of great interest. Additionally, the <span class="hlt">propagation</span> of the initial symmetric (S0) and asymmetric (A0) <span class="hlt">wave</span> modes is important, as these <span class="hlt">wave</span> modes are used for time of arrival estimation. In this investigation, finite element analyses were performed to investigate aspects of Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> in composite plates with active signal excitation. A comparative evaluation of two three-dimensional modeling approaches was performed, with emphasis placed on the <span class="hlt">propagation</span> and velocity of both the S0 and A0 <span class="hlt">wave</span> modes. Results from numerical simulations are compared to experimental results obtained from active AE testing. Of particular interest is the directional dependence of Lamb <span class="hlt">waves</span> in quasi-isotropic carbon/epoxy composite plates. Numerical and experimental results suggest that although a quasi-isotropic composite plate may have the same effective elastic modulus in all in-plane directions, the Lamb <span class="hlt">wave</span> velocity may have some directional dependence. Further numerical analyses were performed to investigate Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> associated with circular cutouts in composite plates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1919572S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1919572S"><span>Field experiments to determine <span class="hlt">wave</span> <span class="hlt">propagation</span> principles and mechanical properties of snow</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Simioni, Stephan; Gebhard, Felix; Dual, Jürg; Schweizer, Jürg</p> <p>2017-04-01</p> <p>To understand the release of snow avalanches by explosions one needs to know how acoustic <span class="hlt">waves</span> travel above and within the snowpack. Hitherto, <span class="hlt">wave</span> <span class="hlt">propagation</span> was investigated in the laboratory with small samples or in the field in the shock <span class="hlt">wave</span> region. We developed a measurement system and layout to derive <span class="hlt">wave</span> attenuation in snow, <span class="hlt">wave</span> speeds and elastic moduli on small-scale (1-2 m) field experiments to close the gap between the lab scale (0.1 m) and the scale of artificial release (10-100 m). We used solid explosives and hammer blows to create the load and accelerometers to measure the resulting <span class="hlt">wave</span> within the snowpack. The strong attenuation we observed indicates that we measured the second longitudinal <span class="hlt">wave</span> which <span class="hlt">propagates</span> through the pore space. The <span class="hlt">wave</span> speeds, however, corresponded to the speeds of the first longitudinal <span class="hlt">wave</span> within the ice skeleton. The elastic moduli were high on the order of several tens of MPa for lower densities (150 kg m-3) and agreed well with earlier lab studies, in particular for the higher densities 250-400 kg m-3). However, the scatter was rather large as expected for in-situ experiments in the layered snow cover. In addition, we measured accelerations during <span class="hlt">propagation</span> saw test experiments. The <span class="hlt">propagation</span> of cracks during this type of snow instability test has mainly been studied by analysing the bending of the slab (due to the saw cut) using particle tracking velocimetry. We used the accelerometers to measure crack <span class="hlt">propagation</span> speeds. The <span class="hlt">wave</span> speeds were slightly higher for most experiments than reported previously. Furthermore, in some experiments, we encountered to different <span class="hlt">wave</span> types with one <span class="hlt">propagating</span> at a higher speed. This finding may be interpreted as the actual crack <span class="hlt">propagation</span> and the settling of the weak layer (collapse <span class="hlt">wave</span>). Our results show that field measurements of <span class="hlt">propagation</span> properties are feasible and that crack <span class="hlt">propagation</span> as observed during <span class="hlt">propagation</span> saw tests may involve different processes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRC..120.4945R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRC..120.4945R"><span>Source location impact on relative <span class="hlt">tsunami</span> strength along the U.S. West Coast</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rasmussen, L.; Bromirski, P. D.; Miller, A. J.; Arcas, D.; Flick, R. E.; Hendershott, M. C.</p> <p>2015-07-01</p> <p><span class="hlt">Tsunami</span> <span class="hlt">propagation</span> simulations are used to identify which <span class="hlt">tsunami</span> source locations would produce the highest amplitude <span class="hlt">waves</span> on approach to key population centers along the U.S. West Coast. The reasons for preferential influence of certain remote excitation sites are explored by examining model time sequences of <span class="hlt">tsunami</span> <span class="hlt">wave</span> patterns emanating from the source. Distant bathymetric features in the West and Central Pacific can redirect <span class="hlt">tsunami</span> energy into narrow paths with anomalously large <span class="hlt">wave</span> height that have disproportionate impact on small areas of coastline. The source region generating the <span class="hlt">waves</span> can be as little as 100 km along a subduction zone, resulting in distinct source-target pairs with sharply amplified <span class="hlt">wave</span> energy at the target. <span class="hlt">Tsunami</span> spectral ratios examined for transects near the source, after crossing the West Pacific, and on approach to the coast illustrate how prominent bathymetric features alter <span class="hlt">wave</span> spectral distributions, and relate to both the timing and magnitude of <span class="hlt">waves</span> approaching shore. To contextualize the potential impact of <span class="hlt">tsunamis</span> from high-amplitude source-target pairs, the source characteristics of major historical earthquakes and <span class="hlt">tsunamis</span> in 1960, 1964, and 2011 are used to generate comparable events originating at the highest-amplitude source locations for each coastal target. This creates a type of "worst-case scenario," a replicate of each region's historically largest earthquake positioned at the fault segment that would produce the most incoming <span class="hlt">tsunami</span> energy at each target port. An amplification factor provides a measure of how the incoming <span class="hlt">wave</span> height from the worst-case source compares to the historical event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010SMaS...19a5015H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010SMaS...19a5015H"><span>Optimizing a spectral element for modeling PZT-induced Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> in thin plates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ha, Sungwon; Chang, Fu-Kuo</p> <p>2010-01-01</p> <p>Use of surface-mounted piezoelectric actuators to generate acoustic ultrasound has been demonstrated to be a key component of built-in nondestructive detection evaluation (NDE) techniques, which can automatically inspect and interrogate damage in hard-to-access areas in real time without disassembly of the structural parts. However, piezoelectric actuators create complex <span class="hlt">waves</span>, which <span class="hlt">propagate</span> through the structure. Having the capability to model piezoelectric actuator-induced <span class="hlt">wave</span> <span class="hlt">propagation</span> and understanding its physics are essential to developing advanced algorithms for the built-in NDE techniques. Therefore, the objective of this investigation was to develop an efficient hybrid spectral element for modeling piezoelectric actuator-induced high-frequency <span class="hlt">wave</span> <span class="hlt">propagation</span> in thin plates. With the hybrid element we take advantage of both a high-order spectral element in the in-plane direction and a linear finite element in the thickness direction in order to efficiently analyze Lamb <span class="hlt">wave</span> <span class="hlt">propagation</span> in thin plates. The hybrid spectral element out-performs other elements in terms of leading to significantly faster computation and smaller memory requirements. Use of the hybrid spectral element is proven to be an efficient technique for modeling PZT-induced (PZT: lead zirconate titanate) <span class="hlt">wave</span> <span class="hlt">propagation</span> in thin plates. The element enables fundamental understanding of PZT-induced <span class="hlt">wave</span> <span class="hlt">propagation</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.7377K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.7377K"><span>Development of a GPS buoy system for monitoring <span class="hlt">tsunami</span>, sea <span class="hlt">waves</span>, ocean bottom crustal deformation and atmospheric water vapor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kato, Teruyuki; Terada, Yukihiro; Nagai, Toshihiko; Koshimura, Shun'ichi</p> <p>2010-05-01</p> <p>We have developed a GPS buoy system for monitoring <span class="hlt">tsunami</span> for over 12 years. The idea was that a buoy equipped with a GPS antenna and placed offshore may be an effective way of monitoring <span class="hlt">tsunami</span> before its arrival to the coast and to give warning to the coastal residents. The key technology for the system is real-time kinematic (RTK) GPS technology. We have successfully developed the system; we have detected <span class="hlt">tsunamis</span> of about 10cm in height for three large earthquakes, namely, the 23 June 2001 Peru earthquake (Mw8.4), the 26 September 2003 Tokachi earthquake (Mw8.3) and the 5 September 2004 earthquake (Mw7.4). The developed GPS buoy system is also capable of monitoring sea <span class="hlt">waves</span> that are mainly caused by winds. Only the difference between <span class="hlt">tsunami</span> and sea <span class="hlt">waves</span> is their frequency range and can be segregated each other by a simple filtering technique. Given the success of GPS buoy experiments, the system has been adopted as a part of the Nationwide Ocean <span class="hlt">Wave</span> information system for Port and HArborS (NOWPHAS) by the Ministry of Land, Infrastructure, Transport and Tourism of Japan. They have established more than eight GPS buoys along the Japanese coasts and the system has been operated by the Port and Airport Research Institute. As a future scope, we are now planning to implement some other additional facilities for the GPS buoy system. The first application is a so-called GPS/Acoustic system for monitoring ocean bottom crustal deformation. The system requires acoustic <span class="hlt">waves</span> to detect ocean bottom reference position, which is the geometrical center of an array of transponders, by measuring distances between a position at the sea surface (vessel) and ocean bottom equipments to return the received sonic <span class="hlt">wave</span>. The position of the vessel is measured using GPS. The system was first proposed by a research group at the Scripps Institution of Oceanography in early 1980's. The system was extensively developed by Japanese researchers and is now capable of detecting ocean</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013NHESD...1.1173O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013NHESD...1.1173O"><span><span class="hlt">Tsunami</span> hazard assessment in the southern Colombian Pacific Basin and a proposal to regenerate a previous barrier island as protection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Otero, L. J.; Restrepo, J. C.; Gonzalez, M.</p> <p>2013-04-01</p> <p>In this study, the <span class="hlt">tsunami</span> hazard posed to 120 000 inhabitants of Tumaco (Colombia) is assessed, and an evaluation and analysis of regenerating the previous El Guano Island for <span class="hlt">tsunami</span> protection is conducted. El Guano Island was a sandy barrier island in front of the city of Tumaco until its disappearance during the <span class="hlt">tsunami</span> of 1979; the island is believed to have played a protective role, substantially reducing the scale of the disaster. The analysis is conducted by identifying seismotectonic parameters and focal mechanisms of <span class="hlt">tsunami</span> generation in the area, determining seven potential generation sources, applying a numerical model for <span class="hlt">tsunami</span> generation and <span class="hlt">propagation</span>, and evaluating the effect of <span class="hlt">tsunamis</span> on Tumaco. The results show that in the current situation, this area is vulnerable to impact and flooding by <span class="hlt">tsunamis</span> originating nearby. El Guano Island was found to markedly reduce flood levels and the energy flux of <span class="hlt">tsunami</span> <span class="hlt">waves</span> in Tumaco during the 1979 <span class="hlt">tsunami</span>. To reduce the risk of flooding due to <span class="hlt">tsunamis</span>, the regeneration and morphological modification of El Guano Island would help to protect Tumaco.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014NHESS..14.1155O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014NHESS..14.1155O"><span><span class="hlt">Tsunami</span> hazard assessment in the southern Colombian Pacific basin and a proposal to regenerate a previous barrier island as protection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Otero, L. J.; Restrepo, J. C.; Gonzalez, M.</p> <p>2014-05-01</p> <p>In this study, the <span class="hlt">tsunami</span> hazard posed to 120 000 inhabitants of Tumaco (Colombia) is assessed, and an evaluation and analysis of regenerating the previous El Guano Island for <span class="hlt">tsunami</span> protection is conducted. El Guano Island was a sandy barrier island in front of the city of Tumaco until its disappearance during the <span class="hlt">tsunami</span> of 1979; the island is believed to have played a protective role, substantially reducing the scale of the disaster. The analysis is conducted by identifying seismotectonic parameters and focal mechanisms of <span class="hlt">tsunami</span> generation in the area, determining seven potential generation sources, applying a numerical model for <span class="hlt">tsunami</span> generation and <span class="hlt">propagation</span>, and evaluating the effect of <span class="hlt">tsunamis</span> on Tumaco. The results show that in the current situation, this area is vulnerable to impact and flooding by <span class="hlt">tsunamis</span> originating nearby. El Guano Island was found to markedly reduce flood levels and the energy flux of <span class="hlt">tsunami</span> <span class="hlt">waves</span> in Tumaco during the 1979 <span class="hlt">tsunami</span>. By reducing the risk of flooding due to <span class="hlt">tsunamis</span>, the regeneration and morphological modification of El Guano Island would help to protect Tumaco.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25618089','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25618089"><span><span class="hlt">Propagation</span> of time-reversed Lamb <span class="hlt">waves</span> in bovine cortical bone in vitro.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, Kang Il; Yoon, Suk Wang</p> <p>2015-01-01</p> <p>The present study aims to investigate the <span class="hlt">propagation</span> of time-reversed Lamb <span class="hlt">waves</span> in bovine cortical bone in vitro. The time-reversed Lamb <span class="hlt">waves</span> were successfully launched at 200 kHz in 18 bovine tibiae through a time reversal process of Lamb <span class="hlt">waves</span>. The group velocities of the time-reversed Lamb <span class="hlt">waves</span> in the bovine tibiae were measured using the axial transmission technique. They showed a significant correlation with the cortical thickness and tended to follow the theoretical group velocity of the lowest order antisymmetrical Lamb <span class="hlt">wave</span> fairly well, consistent with the behavior of the slow guided <span class="hlt">wave</span> in long cortical bones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..MAR.G1255C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..MAR.G1255C"><span>Spin <span class="hlt">wave</span> <span class="hlt">propagation</span> in perpendicular magnetized 20 nm Yttrium Iron Garnet with different antenna design</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Jilei; Stueckler, Tobias; Zhang, Youguang; Zhao, Weisheng; Yu, Haiming; Chang, Houchen; Liu, Tao; Wu, Mingzhong; Liu, Chuanpu; Liao, Zhimin; Yu, Dapeng; Fert Beijing research institute Team; Colorado State University Team; Peking University Collaboration</p> <p></p> <p>Magnonics offers a new way to transport information using spin <span class="hlt">waves</span> free of charge current and could lead to a new paradigm in the area of computing. Forward volume (FV) mode spin <span class="hlt">wave</span> with perpendicular magnetized configuration is suitable for spin <span class="hlt">wave</span> logic device because it is free of non-reciprocity effect. Here, we study FV mode spin <span class="hlt">wave</span> <span class="hlt">propagation</span> in YIG thin film with an ultra-low damping. We integrated differently designed antenna i.e., coplanar waveguide and micro stripline with different dimensions. The k vectors of the spin <span class="hlt">waves</span> defined by the design of the antenna are calculated using Fourier transform. We show FV mode spin <span class="hlt">wave</span> <span class="hlt">propagation</span> results by measuring S12 parameter from vector network analyzer and we extract the group velocity of the FV mode spin <span class="hlt">wave</span> as well as its dispersion relations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhPl...24a3518N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhPl...24a3518N"><span>Correlation of <span class="hlt">wave</span> <span class="hlt">propagation</span> modes in helicon plasma with source tube lengths</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Niu, Chen; Zhao, Gao; Wang, Yu; Liu, Zhongwei; Chen, Qiang</p> <p>2017-01-01</p> <p>Helicon <span class="hlt">wave</span> plasma demonstrates lots of advantages in high coupling efficiency, high density, and low magnetic field. However, the helicon <span class="hlt">wave</span> plasma still meets challenges in applications of material deposition, surface treatment, and electromagnetic thrusters owing to the changeable coupled efficiency and the remarkable non-uniformity. In this paper, we explore the <span class="hlt">wave</span> <span class="hlt">propagation</span> characterization by the B-dot probe in various lengths of source tubes. We find that in a long source tube the standing <span class="hlt">wave</span> appears under the antenna zone, while the traveling <span class="hlt">wave</span> is formed out of the antenna region. The apparent modulation of <span class="hlt">wave</span> amplitude is formed in upstream rather than in downstream of the antenna. In a short source tube, however, there is only standing <span class="hlt">wave</span> <span class="hlt">propagation</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4525157','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4525157"><span>Investigating Alfvénic <span class="hlt">wave</span> <span class="hlt">propagation</span> in coronal open-field regions</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Morton, R. J.; Tomczyk, S.; Pinto, R.</p> <p>2015-01-01</p> <p>The physical mechanisms behind accelerating solar and stellar winds are a long-standing astrophysical mystery, although recent breakthroughs have come from models invoking the turbulent dissipation of Alfvén <span class="hlt">waves</span>. The existence of Alfvén <span class="hlt">waves</span> far from the Sun has been known since the 1970s, and recently the presence of ubiquitous Alfvénic <span class="hlt">waves</span> throughout the solar atmosphere has been confirmed. However, the presence of atmospheric Alfvénic <span class="hlt">waves</span> does not, alone, provide sufficient support for <span class="hlt">wave</span>-based models; the existence of counter-<span class="hlt">propagating</span> Alfvénic <span class="hlt">waves</span> is crucial for the development of turbulence. Here, we demonstrate that counter-<span class="hlt">propagating</span> Alfvénic <span class="hlt">waves</span> exist in open coronal magnetic fields and reveal key observational insights into the details of their generation, reflection in the upper atmosphere and outward <span class="hlt">propagation</span> into the solar wind. The results enhance our knowledge of Alfvénic <span class="hlt">wave</span> <span class="hlt">propagation</span> in the solar atmosphere, providing support and constraints for some of the recent Alfvén <span class="hlt">wave</span> turbulence models. PMID:26213234</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007APS..DPPGP8031A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007APS..DPPGP8031A"><span>Studies of nonlinear interactions between counter-<span class="hlt">propagating</span> Alfv'en <span class="hlt">waves</span> in the LAPD</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Auerbach, D. W.; Perez, J. C.; Carter, T. A.; Boldyrev, S.</p> <p>2007-11-01</p> <p>From a weak turbulence point of view, nonlinear interactions between shear Alfv'en <span class="hlt">waves</span> are fundamental to the energy cascade in low-frequency magnetic turbulence. We report here on an experimental study of counter-<span class="hlt">propagating</span> Alfv'en <span class="hlt">wave</span> interactions in the Large Plasma Device (LAPD) at UCLA. Colliding, orthogonally polarized kinetic Alfv'en <span class="hlt">waves</span> are generated by two antennae, separated by 5m along the guide magnetic field. Magnetic field and langmuir probes record plasma behavior between the antennae. When each antenna is operated separately, linearly polarized Alfv'en <span class="hlt">waves</span> <span class="hlt">propagate</span> in opposite directions along the guide field. When two antennae simultaneously excite counter <span class="hlt">propagating</span> <span class="hlt">waves</span>, we observe multiple side bands in the frequency domain, whose amplitude scales quadratically with <span class="hlt">wave</span> amplitude. In the spatial domain we observe non-linear superposition in the 2D structure of the <span class="hlt">waves</span> and spectral broadening in the perpendicular <span class="hlt">wave</span>-number spectrum. This indicates the presence of nonlinear interaction of the counter <span class="hlt">propagating</span> Alfv'en <span class="hlt">waves</span>, and opens the possiblity to investigate Alfv'enic plasma turbulence in controlled and reproducible laboratory experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1811036L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1811036L"><span>Implementation of a Global Navigation Satellite System (GNSS) Augmentation to <span class="hlt">Tsunami</span> Early Warning Systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>LaBrecque, John</p> <p>2016-04-01</p> <p>The Global Geodetic Observing System has issued a Call for Participation to research scientists, geodetic research groups and national agencies in support of the implementation of the IUGG recommendation for a Global Navigation Satellite System (GNSS) Augmentation to <span class="hlt">Tsunami</span> Early Warning Systems. The call seeks to establish a working group to be a catalyst and motivating force for the definition of requirements, identification of resources, and for the encouragement of international cooperation in the establishment, advancement, and utilization of GNSS for <span class="hlt">Tsunami</span> Early Warning. During the past fifteen years the populations of the Indo-Pacific region experienced a series of mega-thrust earthquakes followed by devastating <span class="hlt">tsunamis</span> that claimed nearly 300,000 lives. The future resiliency of the region will depend upon improvements to infrastructure and emergency response that will require very significant investments from the Indo-Pacific economies. The estimation of earthquake moment magnitude, source mechanism and the distribution of crustal deformation are critical to rapid <span class="hlt">tsunami</span> warning. Geodetic research groups have demonstrated the use of GNSS data to estimate earthquake moment magnitude, source mechanism and the distribution of crustal deformation sufficient for the accurate and timely prediction of <span class="hlt">tsunamis</span> generated by mega-thrust earthquakes. GNSS data have also been used to measure the formation and <span class="hlt">propagation</span> of <span class="hlt">tsunamis</span> via ionospheric disturbances acoustically coupled to the <span class="hlt">propagating</span> surface <span class="hlt">waves</span>; thereby providing a new technique to track <span class="hlt">tsunami</span> <span class="hlt">propagation</span> across ocean basins, opening the way for improving <span class="hlt">tsunami</span> <span class="hlt">propagation</span> models, and providing accurate warning to communities in the far field. These two new advancements can deliver timely and accurate <span class="hlt">tsunami</span> warnings to coastal communities in the near and far field of mega-thrust earthquakes. This presentation will present the justification for and the details of the GGOS Call for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://nws.weather.gov/nthmp/documents/Tsunami_Assessment_2016Update.pdf','USGSPUBS'); return false;" href="http://nws.weather.gov/nthmp/documents/Tsunami_Assessment_2016Update.pdf"><span>U.S. States and Territories National <span class="hlt">Tsunami</span> Hazard Assessment: Historical record and sources for <span class="hlt">waves</span> – Update</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Dunbar, Paula K.; Weaver, Craig S.</p> <p>2015-01-01</p> <p>The first U.S. <span class="hlt">Tsunami</span> Hazard Assessment (Dunbar and Weaver, 2008) was prepared at the request of the National <span class="hlt">Tsunami</span> Hazard Mitigation Program (NTHMP). The NTHMP is a partnership formed between federal and state agencies to reduce the impact of <span class="hlt">tsunamis</span> through hazard assessment, warning guidance, and mitigation. The assessment was conducted in response to a 2005 joint report by the Sub-Committee on Disaster Reduction and the U.S. Group on Earth Observations entitled <span class="hlt">Tsunami</span> Risk Reduction for the United States: A Framework for Action. The first specific action called for in the Framework was to “develop standardized and coordinated <span class="hlt">tsunami</span> hazard and risk assessments for all coastal regions of the United States and its territories.” Since the first assessment, there have been a number of very significant <span class="hlt">tsunamis</span>, including the 2009 Samoa, 2010 Chile, and 2011 Japan <span class="hlt">tsunamis</span>. As a result, the NTHMP requested an update of the U.S. <span class="hlt">tsunami</span> hazard assessment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA.....4971W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA.....4971W"><span>Run-up of <span class="hlt">Tsunamis</span> in the Gulf of Mexico caused by the Chicxulub Impact Event</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weisz, R.; Wünnenmann, K.; Bahlburg, H.</p> <p>2003-04-01</p> <p>The Chicxulub impact event can be investigated on (1) local, (2) regional and in (3) global scales. Our investigations focus on the regional scale, especially on the run-up of <span class="hlt">tsunami</span> <span class="hlt">waves</span> on the coast around the Gulf of Mexico caused by the impact. An impact produces two types of <span class="hlt">tsunami</span> <span class="hlt">waves</span>: (1) the rim <span class="hlt">wave</span>, (2) the collapse <span class="hlt">wave</span>. Both <span class="hlt">waves</span> <span class="hlt">propagate</span> over long distances and reach coastal areas. Depending o