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Sample records for piezometric surface mapping

  1. Interaction of surface water and groundwater in the Nile River basin: isotopic and piezometric evidence

    NASA Astrophysics Data System (ADS)

    Kebede, Seifu; Abdalla, Osman; Sefelnasr, Ahmed; Tindimugaya, Callist; Mustafa, Osman

    2016-12-01

    Past discussions around water-resources management and development in the River Nile basin disregard groundwater resources from the equation. There is an increasing interest around factoring the groundwater resources as an integral part of the Nile Basin water resources. This is hampered by knowledge gap regarding the groundwater resources dynamics (recharge, storage, flow, quality, surface-water/groundwater interaction) at basin scale. This report provides a comprehensive analysis of the state of surface-water/groundwater interaction from the headwater to the Nile Delta region. Piezometric and isotopic (δ18O, δ2H) evidence reveal that the Nile changes from a gaining stream in the headwater regions to mostly a loosing stream in the arid lowlands of Sudan and Egypt. Specific zones of Nile water leakage to the adjacent aquifers is mapped using the two sources of evidence. Up to 50% of the surface-water flow in the equatorial region of the Nile comes from groundwater as base flow. The evidence also shows that the natural direction and rate of surface-water/groundwater interaction is largely perturbed by human activities (diversion, dam construction) particularly downstream of the Aswan High Dam in Egypt. The decrease in discharge of the Nile River along its course is attributed to leakage to the aquifers as well as to evaporative water loss from the river channel. The surface-water/groundwater interaction occurring along the Nile River and its sensitivity to infrastructure development calls for management strategies that account groundwater as an integral part of the Nile Basin resources.

  2. Bone Surface Mapping Method

    PubMed Central

    Fan, Yifang; Fan, Yubo; Li, Zhiyu; Lv, Changsheng; Zhang, Bo

    2012-01-01

    Bone shape is an important factor to determine the bone's structural function. For the asymmetrically shaped and anisotropically distributed bone in vivo, a surface mapping method is proposed on the bases of its geometric transformation invariance and its uniqueness of the principal axes of inertia. Using spiral CT scanning, we can make precise measurements to bone in vivo. The coordinate transformations lead to the principal axes of inertia, with which the prime meridian and the contour can be set. Methods such as tomographic reconstruction and boundary development are employed so that the surface of bone in vivo can be mapped. Experimental results show that the surface mapping method can reflect the shape features and help study the surface changes of bone in vivo. This method can be applied to research into the surface characteristics and changes of organ, tissue or cell whenever its digitalized surface is obtained. PMID:22412952

  3. HI Surface brightness mapping

    NASA Astrophysics Data System (ADS)

    Pen, Ue-Li; Staveley-Smith, Lister; Chang, Tzu-Ching; Peterson, Jeff; Bandura, Kevin

    2008-04-01

    We propose to scan the 2dF survey field with Parkes multibeam in driftscan mode to make a map to cross correlate with galaxy redshifts. This allows a statistical detection of HI large scale structure out to z=0.15. In this cross correlation, the HI in ALL galaxies contributes, not only the bright ones, which significantly boosts the sensitivity. The proposed 40 hours on the fields result in a forecasted 20 sigma detection. The survey volume is 10 million cubic megaparsec, which contain 10^15 solar masses of hydrogen.

  4. Mapping products of Titan's surface

    USGS Publications Warehouse

    Stephan, Katrin; Jaumann, Ralf; Karkoschka, Erich; Barnes, Jason W.; Tomasko, Martin G.; Turtle, Elizabeth P.; Le Corre, Lucille; Langhans, Mirjam; Le Mouelic, Stephane; Lorenz, Ralf D.; Perry, Jason; Brown, Robert H.; Lebreton, Jean-Pierre

    2009-01-01

    Remote sensing instruments aboard the Cassini spacecraft have been observed the surface of Titan globally in the infrared and radar wavelength ranges as well as locally by the Huygens instruments revealing a wealth of new morphological features indicating a geologically active surface. We present a summary of mapping products of Titan's surface derived from data of the remote sensing instruments onboard the Cassini spacecraft (ISS, VIMS, RADAR) as well as the Huygens probe (DISR) that were achieved during the nominal Cassini mission including an overview of Titan's recent nomenclature.

  5. Corrected body surface potential mapping.

    PubMed

    Krenzke, Gerhard; Kindt, Carsten; Hetzer, Roland

    2007-02-01

    In the method for body surface potential mapping described here, the influence of thorax shape on measured ECG values is corrected. The distances of the ECG electrodes from the electrical heart midpoint are determined using a special device for ECG recording. These distances are used to correct the ECG values as if they had been measured on the surface of a sphere with a radius of 10 cm with its midpoint localized at the electrical heart midpoint. The equipotential lines of the electrical heart field are represented on the virtual surface of such a sphere. It is demonstrated that the character of a dipole field is better represented if the influence of the thorax shape is reduced. The site of the virtual reference electrode is also important for the dipole character of the representation of the electrical heart field.

  6. Acoustic visualizations using surface mapping.

    PubMed

    Siltanen, Samuel; Robinson, Philip W; Saarelma, Jukka; Pätynen, Jukka; Tervo, Sakari; Savioja, Lauri; Lokki, Tapio

    2014-06-01

    Sound visualizations have been an integral part of room acoustics studies for more than a century. As acoustic measurement techniques and knowledge of hearing evolve, acousticians need more intuitive ways to represent increasingly complex data. Microphone array processing now allows accurate measurement of spatio-temporal acoustic properties. However, the multidimensional data can be a challenge to display coherently. This letter details a method of mapping visual representations of acoustic reflections from a receiver position to the surfaces from which the reflections originated. The resulting animations are presented as a spatial acoustic analysis tool.

  7. Vesta surface thermal properties map

    USGS Publications Warehouse

    Capria, Maria Teresa; Tosi, F.; De Santis, Maria Cristina; Capaccioni, F.; Ammannito, E.; Frigeri, A.; Zambon, F; Fonte, S.; Palomba, E.; Turrini, D.; Titus, T.N.; Schroder, S.E.; Toplis, M.J.; Liu, J.Y.; Combe, J.-P.; Raymond, C.A.; Russell, C.T.

    2014-01-01

    The first ever regional thermal properties map of Vesta has been derived from the temperatures retrieved by infrared data by the mission Dawn. The low average value of thermal inertia, 30 ± 10 J m−2 s−0.5 K−1, indicates a surface covered by a fine regolith. A range of thermal inertia values suggesting terrains with different physical properties has been determined. The lower thermal inertia of the regions north of the equator suggests that they are covered by an older, more processed surface. A few specific areas have higher than average thermal inertia values, indicative of a more compact material. The highest thermal inertia value has been determined on the Marcia crater, known for its pitted terrain and the presence of hydroxyl in the ejecta. Our results suggest that this type of terrain can be the result of soil compaction following the degassing of a local subsurface reservoir of volatiles.

  8. Conformal Surface Parameterization for Texture Mapping

    DTIC Science & Technology

    1999-03-25

    Conformal Surface Parameterization for Texture Mapping Steven Haker Department of Electrical and Computer Engineering University of Minnesota...also like to thank Professor Victoria Interrante for some very helpful conversations on texture mappings. References [1] S. Angenent, S. Haker , A

  9. Integrable mappings via rational elliptic surfaces

    NASA Astrophysics Data System (ADS)

    Tsuda, Teruhisa

    2004-02-01

    We present a geometric description of the QRT map (which is an integrable mapping introduced by Quispel, Roberts and Thompson) in terms of the addition formula of a rational elliptic surface. By this formulation, we classify all the cases when the QRT map is periodic; and show that its period is 2, 3, 4, 5 or 6. A generalization of the QRT map which acts birationally on a pencil of K3 surfaces, or Calabi-Yau manifolds, is also presented.

  10. Evaluation of the potential of InSAR time series to study the spatio-temporal evolution of piezometric levels in the Madrid aquifer

    NASA Astrophysics Data System (ADS)

    Béjar-Pizarro, M.; Ezquerro Martín, P.; Herrera, G.; Tomás, R.; Guardiola-Albert, C.; Ruiz Hernández, J. M.; Marchamalo Sacristán, M.; Martínez Marín, R.

    2015-11-01

    The Tertiary detritic aquifer of Madrid (TDAM), with an average thickness of 1500 m and a heterogeneous, anisotropic structure, supplies water to Madrid, the most populated city of Spain (3.2 million inhabitants in the metropolitan area). Besides its complex structure, a previous work focused in the north-northwest of Madrid city showed that the aquifer behaves quasi elastically trough extraction/recovery cycles and ground uplifting during recovery periods compensates most of the ground subsidence measured during previous extraction periods (Ezquerro et al., 2014). Therefore, the relationship between ground deformation and groundwater level through time can be simulated using simple elastic models. In this work, we model the temporal evolution of the piezometric level in 19 wells of the TDAM in the period 1997-2010. Using InSAR and piezometric time series spanning the studied period, we first estimate the elastic storage coefficient (Ske) for every well. Both, the Ske of each well and the average Ske of all wells, are used to predict hydraulic heads at the different well locations during the study period and compared against the measured hydraulic heads, leading to very similar errors when using the Ske of each well and the average Ske of all wells: 14 and 16 % on average respectively. This result suggests that an average Ske can be used to estimate piezometric level variations in all the points where ground deformation has been measured by InSAR, thus allowing production of piezometric level maps for the different extraction/recovery cycles in the TDAM.

  11. Spatial and Temporal Variability of Piezometric Head in a Montane Peatland

    NASA Astrophysics Data System (ADS)

    Christensen, W.; Fogg, G. E.

    2010-12-01

    Peatlands (bogs, fens) require perennially saturated soils to prevent the decomposition of organic material. In arid regions with high evapotranspiration rates and little summer precipitation (e.g. Sierra Nevada Mountains), late season groundwater discharge helps maintain saturation, stabilize water temperature, and supply nutrients to the system. Recent studies have shown that subsurface heterogeneity can significantly affect the timing and amount of groundwater discharge from hillslopes. Current climate projections suggest the Sierra Nevada Mountains will experience an increase in winter and spring temperatures, resulting in rain or rain on snow dominating the precipitation regime. The resulting high intensity recharge earlier in the season may significantly reduce the amount of late season groundwater discharge. This in turn may result in warmer surface water temperatures, lower nutrient availability, drier conditions, and lead to decomposition of the peat. A conceptual model of variably saturated subsurface flow in heterogeneous hillslopes is developed using Hydrogeosphere. Hillslope heterogeneity is based on randomly generated discrete fracture networks and expected weathering rates. The spatial and temporal variations of piezometric head in the peatland are investigated and compared to field data from Grass Lake Natural Research Area, Luther Pass, California. The results provide insight into the potential response of hillslope groundwater systems to changes in precipitation patterns.

  12. Evaluation of the impact of water harvesting techniques on the evolution of piezometric head of Ain El Bidha groundwater in Kairouan at the Central part of Tunisia

    NASA Astrophysics Data System (ADS)

    Mechergui, M. Mohamed; Henda Saoudi, Mme

    2016-04-01

    This study aims to assess the impact of water harvesting constructed hydraulic structures (big and small dams, terraces, seuils for recharge…) on the evolution of piezometric head of Ain El Beidha groundwater table. The measurements of depth of water table, taken at the end of rain season and at the end of irrigation season, in many piezometers and monitoring wells, for a long period of observation before and after implementation of all the hydraulic structures, were used with the cumulative rain to the highest water table to diagnostic the effect of natural recharge and constructed hydraulic structures. According to the analysis of curves illustrating the evolution of piezometric head and rainfall over time, it was shown that despite the fact that the same amount of rain fall on the total area in the limits of Ain El Beidha groundwater table, the piezometers respond differently. This is because there are many sources of recharge and many factors affecting the recharge. First of all, the aquifer is divided in four compartments (the calcareous formation of Djebel El Houyareb, the plio-quaternary formation, the Miocene formation: Baglia and Saouaf). All those respond differently to the recharge by their capacity of infiltration and their hydrodynamic characteristics. The recharge of the groundwater table was increased by the implementation of small soil and water conservation structures, artificial lakes, El Haouareb Dam, run off in the natural Oued bads and seuils for recharge installed in the bads of oueds. The different piezometric drown maps were used to determine the flow direction and hydraulic gradient in order to identify the recharge areas, while tracking maps for three equal piezometric heads 210 m 300 m and 370 m established over different years made it possible to assess the impact of hydraulic structures, namely the effect of SWC and Ben Zitoun Lake. To illustrate the impact of El Houareb dam on the groundwater, the piezometric maps and local values

  13. Active Free Surface Density Maps

    NASA Astrophysics Data System (ADS)

    Çelen, S.

    2016-10-01

    Percolation problems were occupied to many physical problems after their establishment in 1957 by Broadbent and Hammersley. They can be used to solve complex systems such as bone remodeling. Volume fraction method was adopted to set some algorithms in the literature. However, different rate of osteoporosis could be observed for different microstructures which have the same mass density, mechanical stimuli, hormonal stimuli and nutrition. Thus it was emphasized that the bone might have identical porosity with different specific surfaces. Active free surface density of bone refers the used total area for its effective free surface. The purpose of this manuscript is to consolidate a mathematical approach which can be called as “active free surface density maps” for different surface patterns and derive their formulations. Active free surface density ratios were calculated for different Archimedean lattice models according to Helmholtz free energy and they were compared with their site and bond percolation thresholds from the background studies to derive their potential probability for bone remodeling.

  14. Hyperbolic Harmonic Mapping for Surface Registration.

    PubMed

    Shi, Rui; Zeng, Wei; Su, Zhengyu; Jiang, Jian; Damasio, Hanna; Lu, Zhonglin; Wang, Yalin; Yau, Shing-Tung; Gu, Xianfeng

    2016-05-12

    Automatic computation of surface correspondence via harmonic map is an active research field in computer vision, computer graphics and computational geometry. It may help document and understand physical and biological phenomena and also has broad applications in biometrics, medical imaging and motion capture inducstries. Although numerous studies have been devoted to harmonic map research, limited progress has been made to compute a diffeomorphic harmonic map on general topology surfaces with landmark constraints. This work conquers this problem by changing the Riemannian metric on the target surface to a hyperbolic metric so that the harmonic mapping is guaranteed to be a diffeomorphism under landmark constraints. The computational algorithms are based on Ricci flow and nonlinear heat diffusion methods. The approach is general and robust. We employ our algorithm to study the constrained surface registration problem which applies to both computer vision and medical imaging applications. Experimental results demonstrate that, by changing the Riemannian metric, the registrations are always diffeomorphic and achieve relatively high performance when evaluated with some popular surface registration evaluation standards.

  15. Impervious surface mapping with Quickbird imagery

    PubMed Central

    Lu, Dengsheng; Hetrick, Scott; Moran, Emilio

    2010-01-01

    This research selects two study areas with different urban developments, sizes, and spatial patterns to explore the suitable methods for mapping impervious surface distribution using Quickbird imagery. The selected methods include per-pixel based supervised classification, segmentation-based classification, and a hybrid method. A comparative analysis of the results indicates that per-pixel based supervised classification produces a large number of “salt-and-pepper” pixels, and segmentation based methods can significantly reduce this problem. However, neither method can effectively solve the spectral confusion of impervious surfaces with water/wetland and bare soils and the impacts of shadows. In order to accurately map impervious surface distribution from Quickbird images, manual editing is necessary and may be the only way to extract impervious surfaces from the confused land covers and the shadow problem. This research indicates that the hybrid method consisting of thresholding techniques, unsupervised classification and limited manual editing provides the best performance. PMID:21643434

  16. High Resolution Camera for Mapping Titan Surface

    NASA Technical Reports Server (NTRS)

    Reinhardt, Bianca

    2011-01-01

    Titan, Saturn's largest moon, has a dense atmosphere and is the only object besides Earth to have stable liquids at its surface. The Cassini/Huygens mission has revealed the extraordinary breadth of geological processes shaping its surface. Further study requires high resolution imaging of the surface, which is restrained by light absorption by methane and scattering from aerosols. The Visual and Infrared Mapping Spectrometer (VIMS) onboard the Cassini spacecraft has demonstrated that Titan's surface can be observed within several windows in the near infrared, allowing us to process several regions in order to create a geological map and to determine the morphology. Specular reflections monitored on the lakes of the North Pole show little scattering at 5 microns, which, combined with the present study of Titan's northern pole area, refutes the paradigm that only radar can achieve high resolution mapping of the surface. The present data allowed us to monitor the evolution of lakes, to identify additional lakes at the Northern Pole, to examine Titan's hypothesis of non-synchronous rotation and to analyze the albedo of the North Pole surface. Future missions to Titan could carry a camera with 5 micron detectors and a carbon fiber radiator for weight reduction.

  17. Mapping products of Titan's surface: Chapter 19

    USGS Publications Warehouse

    Stephan, Katrin; Jaumann, Ralf; Karkoschka, Erich; Kirk, Randolph L.; Barnes, Jason W.; Tomasko, Martin G.; Turtle, Elizabeth P.; Le Corre, Lucille; Langhans, Mirjam; Le Mouélic, Stéphane; Lorenz, Ralph D.; Perry, Jason; Brown, Robert; Lebreton, Jean-Pierre; Waite, J. Hunter

    2010-01-01

    Remote sensing instruments aboard the Cassini spacecraft have been observed the surface of Titan globally in the infrared and radar wavelength ranges as well as locally by the Huygens instruments revealing a wealth of new morphological features indicating a geologically active surface. We present a summary of mapping products of Titan's surface derived from data of the remote sensing instruments onboard the Cassini spacecraft (ISS, VIMS, RADAR) as well as the Huygens probe (DISR) that were achieved during the nominal Cassini mission including an overview of Titan's recent nomenclature.

  18. Mapping surface mineralogy using imaging spectrometry

    NASA Astrophysics Data System (ADS)

    Kruse, Fred A.

    2012-01-01

    Imaging spectrometry, simultaneous measurement of spectra and images in up to hundreds of spectral channels or bands, is a proven technology for identifying and mapping minerals based on their reflectance or emissivity signatures. Also known as hyperspectral imaging or "HSI", extraction of key spectral signatures from these data allows direct identification of iron minerals such as hematite, goethite, and jarosite in the visible/near infrared (VNIR); clays, carbonates, micas, sulfates, and other minerals in the short wave infrared (SWIR); and silicates and carbonates in the long wave infrared (LWIR). The unique capability of imaging spectrometry to produce detailed maps of the spatial distribution of specific minerals, mineral assemblages, and mineral variability on the surface of Earth makes it an ideal tool for enhanced geomorphic mapping. Case histories illustrate the use of HSI for characterizing and mapping active and relict geothermal/hydrothermal systems and determining relations between mineralogy and derived landforms. Imaging spectrometry, used in conjunction with complimentary datasets such as InSAR (Interferometric Synthetic Aperture Radar), Light Detection and Ranging (LiDAR), or stereo (photogrammetric-derived) digital elevation models (DEMs), provides a unique means of visualizing the spatial distribution and association of mineralogy with topography, thus contributing to the understanding of the relations between geology and landscape and to improved interpretation of surface geologic processes.

  19. Dawn Maps the Surface Composition of Vesta

    NASA Technical Reports Server (NTRS)

    Prettyman, T.; Palmer, E.; Reedy, R.; Sykes, M.; Yingst, R.; McSween, H.; DeSanctis, M. C.; Capaccinoni, F.; Capria, M. T.; Filacchione, G.; Magni, G.; Ammannito, E.; Carraro, F.; Coradini, A.; Fonte, S.; Noschese, R.; Tosi, F.; Blewett, D.; Denevi, B.; Lawrence, D.; Buratti, B.; Raymond, C. A.; Combe, J. P.; McCord, T.; Forni, O.

    2011-01-01

    By 7-October-2011, the Dawn mission will have completed Survey orbit and commenced high altitude mapping of 4-Vesta. We present a preliminary analysis of data acquired by Dawn's Framing Camera (FC) and the Visual and InfraRed Spectrometer (VIR) to map mineralogy and surface temperature, and to detect and quantify surficial OH. The radiometric calibration of VIR and FC is described. Background counting data acquired by GRaND are used to determine elemental detection limits from measurements at low altitude, which will commence in November. Geochemical models used in the interpretation of the data are described. Thermal properties, mineral-, and geochemical-data are combined to provide constraints on Vesta s formation and thermal evolution, the delivery of exogenic materials, space weathering processes, and the origin of the howardite, eucrite, and diogenite (HED) meteorites.

  20. Solid surface mapping by inverse gas chromatography.

    PubMed

    Gutiérrez, M C; Osuna, S; Baráibar, I

    2005-09-16

    Inverse gas chromatography (IGC) at infinite dilution, is a technique for characterising solid surfaces. Current practice is the injection of n-alkane homologous series to obtain the free energy of adsorption of the CH2 group, from which the London component of the solid surface free energy, gamma(d)s, is calculated. A value around 40 mJ/m2 is obtained for poly(ethylene), and 30 mJ/m2 for a clean glass fibre, while the potential surface interactivity of a glass fibre is far greater than that of poly(ethylene). A specific component of the surface, in mJ/m2, should be calculated in order to obtain significant parameters. As applied up to date, when calculating the specific component of the surface energy, the fact that W(sp)a energy values are in a totally different scale than AN or DN values is a major drawback. Consequently, Ka and Kb values obtained are in arbitrary energy units, different from those of the London component measured by injecting the n-alkane series. This paper proposes a method to obtain Ka and Kb values of the surface in the same energetic scale than the London component. The method enables us to correct the traditional London component of a solid, obtaining a new value, where the amount of WaCH2 accounting for Debye interactions with polar sites, is excluded. As a result, an approach to surface mapping is performed in several different substrate materials. We show results obtained on different solid surfaces: poly(ethylene), clean glass fibre, glass beads, chemically modified glass beads and carbon fibre.

  1. Contribution of piezometric measurement on knowledge and management of low water levels

    NASA Astrophysics Data System (ADS)

    Bessiere, Hélène; Stollsteiner, Philippe; Allier, Delphine; Nicolas, Jérôme; Gourcy, Laurence

    2014-05-01

    This article is based on a BRGM study on piezometric indicators, threshold values of discharges and groundwater levels for the assessment of potentially pumpable volumes of chalky watersheds. A method for estimating low water levels from groundwater levels is presented from three examples of chalk aquifer; the first one is located in Picardy and the two other in the Champagne Ardennes region. Piezometers with "annual" cycles, used in these examples, are supposed to be representative of the aquifer hydrodynamics. The analysis leads to relatively precise and satisfactory relationships between groundwater levels and observed discharges for this chalky context. These relationships may be useful for monitoring, validation, extension or reconstruction of the low water flow. On the one hand, they allow defining the piezometric levels corresponding to the different alert thresholds of river discharges. On the other hand, they clarify the distribution of low water flow from runoff or the draining of the aquifer. Finally, these correlations give an assessment of the minimum flow for the coming weeks using of the rate of draining of the aquifer. Nevertheless the use of these correlations does not allow to optimize the value of pumpable volumes because it seems to be difficult to integrate the amount of the effective rainfall that may occur during the draining period. In addition, these relationships cannot be exploited for multi-annual cycle systems. In these cases, the solution seems to lie on the realization of a rainfall-runoff-piezometric level model. Therefore, two possibilities are possible. The first one is to achieve each year, on a given date, a forecast for the days or months to come with various frequential distributions rainfalls. However, the forecast must be reiterated each year depending on climatic conditions. The principle of the second method is to simulate forecasts for different rainfall intensities and following different initial conditions. The results

  2. Photoelectric scanner makes detailed work function maps of metal surface

    NASA Technical Reports Server (NTRS)

    Rasor, N. S.

    1966-01-01

    Photoelectric scanning device maps the work function of a metal surface by scanning it with a light spot and measuring the resulting photocurrent. The device is capable of use over a range of surface temperatures.

  3. Reproducibility of crop surface maps extracted from Unmanned Aerial Vehicle (UAV) derived digital surface maps

    NASA Astrophysics Data System (ADS)

    Parkes, Stephen D.; McCabe, Matthew F.; Al-Mashhawari, Samir K.; Rosas, Jorge

    2016-10-01

    Crop height measured from UAVs fitted with commercially available RGB cameras provide an affordable alternative to retrieve field scale high resolution estimates. The study presents an assessment of between flight reproducibility of Crop Surface Maps (CSM) extracted from Digital Surface Maps (DSM) generated by Structure from Motion (SfM) algorithms. Flights were conducted over a centre pivot irrigation system covered with an alfalfa crop. An important step in calculating the absolute crop height from the UAV derived DSM is determining the height of the underlying terrain. Here we use automatic thresholding techniques applied to RGB vegetation index maps to classify vegetated and soil pixels. From interpolation of classified soil pixels, a terrain map is calculated and subtracted from the DSM. The influence of three different thresholding techniques on CSMs are investigated. Median Alfalfa crop heights determined with the different thresholding methods varied from 18cm for K means thresholding to 13cm for Otsu thresholding methods. Otsu thresholding also gave the smallest range of crop heights and K means thresholding the largest. Reproducibility of median crop heights between flight surveys was 4-6cm for all thresholding techniques. For the flight conducted later in the afternoon shadowing caused soil pixels to be classified as vegetation in key locations around the domain, leading to lower crop height estimates. The range of crop heights was similar for both flights using K means thresholding (35-36cm), local minimum thresholding depended on whether raw or normalised RGB intensities were used to calculate vegetation indices (30-35cm), while Otsu thresholding had a smaller range of heights and varied most between flights (26-30cm). This study showed that crop heights from multiple survey flights are comparable, however, they were dependent on the thresholding method applied to classify soil pixels and the time of day the flight was conducted.

  4. Ground Surface Visualization Using Red Relief Image Map for a Variety of Map Scales

    NASA Astrophysics Data System (ADS)

    Chiba, T.; Hasi, B.

    2016-06-01

    There are many methods to express topographical features of ground surface. In which, contour map has been the traditional method and along with development of digital data, surface model such as shaded relief map has been using for ground surface expression. Recently, data acquisition has been developed very much quick, demanding more advanced visualization method to express ground surface so as to effectively use the high quality data. In this study, the authors using the Red Relief Image Map (RRIM, Chiba et al., 2008) to express ground surface visualization for a variety of map scales. The authors used 30 m mesh data of SRTM to show the topographical features of western Mongolian and micro-topographical features of ground surface in tectonically active regions of Japan. The results show that, compared to traditional and other similar methods, the RRIM can express ground surface more precisely and 3-dimensionally, suggested its advanced usage for many fields of topographical visualization.

  5. Contribution of piezometric measurement to knowledge and management of low water levels: examples on the chalk aquifer in the Champagne Ardennes region

    NASA Astrophysics Data System (ADS)

    Stollsteiner, P.; Bessiere, H.; Nicolas, J.; Allier, D.; Berthet, O.

    2015-04-01

    This article is based on a BRGM study on piezometric indicators, threshold values of discharge and groundwater levels for the assessment of potentially-exploitable water resources of chalky watersheds. A method for estimating low water levels based on groundwater levels is presented from three examples representing chalk aquifers with different cycles: annual, combined and interannual. The first is located in Picardy and the two others in the Champagne-Ardennes region. Piezometers with annual cycles, used in these examples, are supposed to be representative of the aquifer hydro-dynamics. Except for multi-annual systems, the analysis between discharge measurements at a hydrometric station and groundwater levels measured at a piezometer representative of the main aquifer, leads to relatively precise and satisfactory relationships within a chalky context. These relationships may be useful for monitoring, validation, extension or reconstruction of the low water flow data. On the one hand, they allow definition of the piezometric levels corresponding to the different alert thresholds of river discharges. On the other hand, they clarify the proportions of low surface water flow from runoff or drainage of the aquifer. Finally, these correlations give an assessment of the minimum flow for the coming weeks. However, these correlations cannot be used to optimize the value of the exploitable water resource because it seems to be difficult to integrate the value of the effective rainfall that could occur during the draining period. Moreover, in the case of multi-annual systems, the solution is to attempt a comprehensive system modelling and, if it is satisfactory, using the simulated values to get rid of parasites or running the model for forecasting purposes.

  6. A New Perspective on Surface Weather Maps

    ERIC Educational Resources Information Center

    Meyer, Steve

    2006-01-01

    A two-dimensional weather map is actually a physical representation of three-dimensional atmospheric conditions at a specific point in time. Abstract thinking is required to visualize this two-dimensional image in three-dimensional form. But once that visualization is accomplished, many of the meteorological concepts and processes conveyed by the…

  7. Vesta Mineralogy: VIR maps Vesta's surface

    NASA Technical Reports Server (NTRS)

    Coradina, A.; DeSanctis, M.; Ammannito, E.; Capaccioni, F.; Capria, T.; Carraro, F.; Cartacci, M.; Filacchione, G.; Fonte, S.; Magni, G.; Noschese, R.; Tosi, F.; Barucci, A.; Federico, C.; Frigeri, A.; Fulchigoni, M.; Langevin, Y.; Marchi, S.; Palomba, E.; Turrini, D.; McCord, T.; McFadden, L. A.; Pieters, C.; Raymond, C. A.; Russell, C. T.

    2011-01-01

    The Dawn mission will have completed Survey orbit around 4 Vesta by the end of August 2011. We present a preliminary analysis of data acquired by the Visual and InfraRed Spectrometer (VIR) to map Vesta mineralogy. Thermal properties and mineralogical data are combined to provide constraints on Vesta's formation and thermal evolution. delivery of exogenic materials, space weathering processes, and origin of the howardite. eucrite, and diogenite (HED) meteorites.

  8. Protein-surface interaction maps for ion-exchange chromatography.

    PubMed

    Freed, Alexander S; Cramer, Steven M

    2011-04-05

    In this paper, protein-surface interaction maps were generated by performing coarse-grained protein-surface calculations. This approach allowed for the rapid determination of the protein-surface interaction energies at a range of orientations and distances. Interaction maps of lysozyme indicated that there was a contiguous series of orientations corresponding to several adjacent preferred binding regions on the protein surface. Examination of these orientations provided insight into the residues involved in surface interactions, which qualitatively agreed with the retention data for single-site mutants. Interaction maps of lysozyme single-site mutants were also generated and provided significant insight into why these variants exhibited significant differences in their chromatographic behavior. This approach was also employed to study the binding behavior of CspB and related mutants. The results indicated that, in addition to describing general trends in the data, these maps provided significant insight into retention data of the single-site mutants. In particular, subtle retention trends observed with the K12 and K13 mutants were well-described using this interaction map approach. Finally, the number of interaction points with energies stronger than -2 kcal/mol was shown to be able to semi-quantitatively predict the behavior of most of the mutants. This rapid approach for calculating protein-surface interaction maps is expected to facilitate future method development for separating closely related protein variants in ion-exchange systems.

  9. A new 1.6-micron map of Titan's surface

    NASA Astrophysics Data System (ADS)

    Roe, H. G.; de Pater, I.; Gibbard, S. G.; Macintosh, B. A.; Max, C. E.; Young, E. F.; Brown, M. E.; Bouchez, A. H.

    2004-06-01

    We present a new map of Titan's surface obtained in the spectral `window' at ~1.6 μm between strong methane absorption. This pre-Cassini view of Titan's surface was created from images obtained using adaptive optics on the W.M. Keck II telescope and is the highest resolution map yet made of Titan's surface. Numerous surface features down to the limits of the spatial resolution (~200-300 km) are apparent. No features are easily identifiable in terms of their geologic origin, although several are likely craters.

  10. Mapping Surface Features Produced by an Active Landslide

    NASA Astrophysics Data System (ADS)

    Parise, Mario; Gueguen, Erwan; Vennari, Carmela

    2016-10-01

    A large landslide reactivated on December 2013, at Montescaglioso, southern Italy, after 56 hours of rainfall. The landslide disrupted over 500 m of a freeway, involved a few warehouses, a supermarket, and private homes. After the event, it has been performed field surveys, aided by visual analysis of terrestrial and helicopter photographs, to compile a map of the surface deformations. The geomorphological features mapped included single fractures, sets of fractures, tension cracks, trenches, and pressure ridges. In this paper we present the methodology used, the map obtained through the intensive field work, and discuss the main surface features produced by the landslide.

  11. Seasonal, Episodic and Periodic Changes in Terrestrial Water Storage Recorded By DEEP Piezometric Monitoring in the Ganges/Brahmaputra/Meghna DELTA

    NASA Astrophysics Data System (ADS)

    Burgess, W. G.; Shamsudduha, M.; Taylor, R. G.; Ahmed, K. M.; Mukherjee, A.; Lapworth, D.; Zahid, A.

    2014-12-01

    Piezometric monitoring in vertical profile at sites across the southern and coastal floodplains of the Ganges/Brahmaputra/Meghna (GBM) delta confirms gravitational flow in sediments of the Bengal Aquifer System (BAS) to a depth of at least 320 m (the maximum depth of measurement). Individual and paired records of groundwater head indicate seasonal recovery and recession of water storage, periodic and episodic ground surface loading, and earth tide responses. Lunar periodicity in groundwater head fluctuation coincident with tide height at one coastal site is consistent with tidal surface loading/unloading. Diurnal tidal fluctuations in the same record change amplitude and shift phase with depth, also indicative of surface loading/unloading. Transience in the surface loading signals with depth is governed by the vertically integrated hydraulic properties of the thick BAS sedimentary sequence. Inland, earth tide responses of smaller amplitude and lacking phase shift with depth are ubiquitous in the background signal. Most records include clearly resolvable episodic deflections in the order of 0.1 m water head and up to 0.5 m water head, near simultaneous with depth, corresponding to individual episodes of rainfall. The episodic head deflections provide a record of change in terrestrial water storage (ΔTWS) comprising undifferentiated surface water flooding, soil moisture and shallow groundwater recharge - a direct land-based equivalent of satellite estimates of ΔTWS. Enigmatic short-term recession from individual deflection peaks may be related to elastic deformation and ground surface lowering under terrestrial water storage loading.

  12. Mapping surface disturbance from wind farms

    NASA Astrophysics Data System (ADS)

    Diffendorfer, James E.

    2013-04-01

    Wind energy is one of the fastest growing segments of the electricity market and this trend will likely continue as countries strive to reduce CO2 production while meeting growing energy demands. One impact of wind facilities is surface disturbance, including roads, that lead to habitat loss and fragmentation. Numerous studies of wind power utilize estimates of surface disturbance for GIS-based modeling or basic calculations of the land area required to generate energy using wind. However published estimates of the land use required for a MW of electricity from wind facilities vary by more than 10 times (0.83 to 250 MW/Km2). We report results from a geospatial analysis of 39 wind facilities in the United States that we fully digitized using high resolution photo-imagery. The selected sites and analyses were designed to elucidate the effects of turbine size, topography, and land use on the area requirements of wind facilities. The results indicate point estimates of average surface disturbance/MW have wide levels of variation, explained primarily by Landcover and Topography. Wind facilities in agricultural landscapes had smaller surface disturbance/ha than facilities in forests and shrublands, and facilities in relatively flat topography had smaller surface disturbance/ha than facilities on hills, ridges, or mesas. Land use, topography, and turbine size all influenced turbine spacing. The statistical models suggest we can predict geographic locations where new wind facilities could be placed with minimized surface disturbance.

  13. Application of a simple cerebellar model to geologic surface mapping

    USGS Publications Warehouse

    Hagens, A.; Doveton, J.H.

    1991-01-01

    Neurophysiological research into the structure and function of the cerebellum has inspired computational models that simulate information processing associated with coordination and motor movement. The cerebellar model arithmetic computer (CMAC) has a design structure which makes it readily applicable as an automated mapping device that "senses" a surface, based on a sample of discrete observations of surface elevation. The model operates as an iterative learning process, where cell weights are continuously modified by feedback to improve surface representation. The storage requirements are substantially less than those of a conventional memory allocation, and the model is extended easily to mapping in multidimensional space, where the memory savings are even greater. ?? 1991.

  14. Compositional Mapping of Europa's Surface with SUDA

    NASA Astrophysics Data System (ADS)

    Kempf, S.; Sternovsky, Z.; Horanyi, M.; Hand, K. P.; Srama, R.; Postberg, F.; Altobelli, N.; Gruen, E.; Gudipati, M. S.; Schmidt, J.; Zolotov, M. Y.; Tucker, S.; Hoxie, V. C.; Kohnert, R.

    2015-12-01

    The Surface Mass Analyzer (SUDA) measures the composition of ballistic dust particles populating the thin exospheres that were detected around each of the Galilean moons. Since these grains are direct samples from the moons' icy surfaces, unique composition data will be obtained that will help to define and constrain the geological activities on and below the moons' surface. SUDA will make a vital contribution to NASA's mission to Europa and provide key answers to its main scientific questions about the surface composition, habitability, the icy crust, and exchange processes with the deeper interior of the Jovian icy moon Europa. SUDA is a time-of- flight, reflectron-type impact mass spectrometer, optimised for a high mass resolution which only weakly depends on the impact location. The small size, low mass and large sensitive area meet the challenging demands of mission to Europa. A full-size prototype SUDA instrument was built in order to demonstrate its performance through calibration experiments at the dust accelerator at NASA's IMPACT institute at Boulder, CO, with a variety of cosmo-chemically relevant dust analogues. The effective mass resolution of m/Δm of 150-300 is achieved for mass range of interest m = 1-150.

  15. Surface mineral maps of Afghanistan derived from HyMap imaging spectrometer data, version 2

    USGS Publications Warehouse

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.

    2013-01-01

    This report presents a new version of surface mineral maps derived from HyMap imaging spectrometer data collected over Afghanistan in the fall of 2007. This report also describes the processing steps applied to the imaging spectrometer data. The 218 individual flight lines composing the Afghanistan dataset, covering more than 438,000 square kilometers, were georeferenced to a mosaic of orthorectified Landsat images. The HyMap data were converted from radiance to reflectance using a radiative transfer program in combination with ground-calibration sites and a network of cross-cutting calibration flight lines. The U.S. Geological Survey Material Identification and Characterization Algorithm (MICA) was used to generate two thematic maps of surface minerals: a map of iron-bearing minerals and other materials, which have their primary absorption features at the shorter wavelengths of the reflected solar wavelength range, and a map of carbonates, phyllosilicates, sulfates, altered minerals, and other materials, which have their primary absorption features at the longer wavelengths of the reflected solar wavelength range. In contrast to the original version, version 2 of these maps is provided at full resolution of 23-meter pixel size. The thematic maps, MICA summary images, and the material fit and depth images are distributed in digital files linked to this report, in a format readable by remote sensing software and Geographic Information Systems (GIS). The digital files can be downloaded from http://pubs.usgs.gov/ds/787/downloads/.

  16. Mapping and Quantifying Surface Charges on Clay Nanoparticles.

    PubMed

    Liu, Jun; Gaikwad, Ravi; Hande, Aharnish; Das, Siddhartha; Thundat, Thomas

    2015-09-29

    Understanding the electrical properties of clay nanoparticles is very important since they play a crucial role in every aspect of oil sands processing, from bitumen extraction to sedimentation in mature fine tailings (MFT). Here, we report the direct mapping and quantification of surface charges on clay nanoparticles using Kelvin probe force microscopy (KPFM) and electrostatic force microscopy (EFM). The morphology of clean kaolinite clay nanoparticles shows a layered structure, while the corresponding surface potential map shows a layer-dependent charge distribution. More importantly, a surface charge density of 25 nC/cm(2) was estimated for clean kaolinite layers by using EFM measurements. On the other hand, the EFM measurements show that the clay particles obtained from the tailings demonstrate a reduced surface charge density of 7 nC/cm(2), which may be possibly attributed to the presence of various bituminous compounds residing on the clay surfaces.

  17. 43 CFR 3931.60 - Maps of underground and surface mine workings and in situ surface operations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Maps of underground and surface mine... § 3931.60 Maps of underground and surface mine workings and in situ surface operations. Maps of.... All maps must be appropriately marked with reference to government land marks or lines and...

  18. 43 CFR 3931.60 - Maps of underground and surface mine workings and in situ surface operations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Maps of underground and surface mine... § 3931.60 Maps of underground and surface mine workings and in situ surface operations. Maps of.... All maps must be appropriately marked with reference to government land marks or lines and...

  19. 43 CFR 3931.60 - Maps of underground and surface mine workings and in situ surface operations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Maps of underground and surface mine... § 3931.60 Maps of underground and surface mine workings and in situ surface operations. Maps of.... All maps must be appropriately marked with reference to government land marks or lines and...

  20. From Surface Data to 3D Geologic Maps

    NASA Astrophysics Data System (ADS)

    Dhont, D.; Luxey, P.; Longuesserre, V.; Monod, B.; Guillaume, B.

    2008-12-01

    New trends in earth sciences are mostly related to technologies allowing graphical representations of the geology in 3D. However, the concept of 3D geologic map is commonly misused. For instance, displays of geologic maps draped onto DEM in rotating perspective views have been misleadingly called 3D geologic maps, but this still cannot provide any volumetric underground information as a true 3D geologic map should. Here, we present a way to produce mathematically and geometrically correct 3D geologic maps constituted by the volume and shape of all geologic features of a given area. The originality of the method is that it is based on the integration of surface data only consisting of (1) geologic maps, (2) satellite images, (3) DEM and (4) bedding dips and strikes. To generate 3D geologic maps, we used a 3D geologic modeler that combines and extrapolates the surface information into a coherent 3D data set. The significance of geometrically correct 3D geologic maps is demonstrated for various geologic settings and applications. 3D models are of primarily importance for educational purposes because they reveal features that standard 2D geologic maps by themselves could not show. The 3D visualization helps in the understanding of the geometrical relationship between the different geologic features and, in turn, for the quantification of the geology at the regional scale. Furthermore, given the logistical challenges associated with modern oil and mineral exploration in remote and rugged terrain, these volume-based models can provide geological and commercial insight prior to seismic evaluation.

  1. Multichannel analysis of surface waves to map bedrock

    USGS Publications Warehouse

    Miller, Richard D.; Xia, Jianghai; Park, Choon B.; Ivanov, Julian M.

    1999-01-01

    High velocity gradients within the shear wave velocity field consistent with drill confirmed bedrock are considered diagnostic of the bedrock surface and were used to map the top of bedrock on all four lines connected at this site. Calculating the shear wave velocity field from surface wave arrivals was accomplished with a high degree of accuracy regardless of cultural noise. Improved resolution on the surface of the bedrock provides insight into the texture of bedrock and permits identification and appraisal of short wavelength variations in the bedrock surface.

  2. Mapping Methane in Titan's Atmosphere near Titan's Surface

    NASA Astrophysics Data System (ADS)

    Young, Eliot; Soderblom, Jason; Barnes, Jason

    2016-06-01

    Titan's atmospheric methane may be coupled to sources and sinks on its surface. In order to map methane concentrations in layers just above Titan's surface, we use data sets in which locations on Titan are imaged from a variety of viewing angles (and within a short time span). We also use a radiative transfer code based on the Markov Chain method of Esposito and House (1978, AJ 219, 1058) to accommodate spherical atmospheric geometries. We report on (a) selected Cassini/VIMS flybys that image terrain on Titan from different angles, (b) the expected vertical resolution of methane maps near the surface from these flybys and (c) preliminary results: 3D methane and haze distributions and surface albedos.

  3. New algorithms to map asymmetries of 3D surfaces.

    PubMed

    Combès, Benoît; Prima, Sylvain

    2008-01-01

    In this paper, we propose a set of new generic automated processing tools to characterise the local asymmetries of anatomical structures (represented by surfaces) at an individual level, and within/between populations. The building bricks of this toolbox are: (1) a new algorithm for robust, accurate, and fast estimation of the symmetry plane of grossly symmetrical surfaces, and (2) a new algorithm for the fast, dense, nonlinear matching of surfaces. This last algorithm is used both to compute dense individual asymmetry maps on surfaces, and to register these maps to a common template for population studies. We show these two algorithms to be mathematically well-grounded, and provide some validation experiments. Then we propose a pipeline for the statistical evaluation of local asymmetries within and between populations. Finally we present some results on real data.

  4. Description and evaluation of a surface runoff susceptibility mapping method

    NASA Astrophysics Data System (ADS)

    Lagadec, Lilly-Rose; Patrice, Pierre; Braud, Isabelle; Chazelle, Blandine; Moulin, Loïc; Dehotin, Judicaël; Hauchard, Emmanuel; Breil, Pascal

    2016-10-01

    Surface runoff is the hydrological process at the origin of phenomena such as soil erosion, floods out of rivers, mudflows, debris flows and can generate major damage. This paper presents a method to create maps of surface runoff susceptibility. The method, called IRIP (Indicator of Intense Pluvial Runoff, French acronym), uses a combination of landscape factors to create three maps representing the susceptibility (1) to generate, (2) to transfer, and (3) to accumulate surface runoff. The method input data are the topography, the land use and the soil type. The method aims to be simple to implement and robust for any type of study area, with no requirement for calibration or specific input format. In a second part, the paper focuses on the evaluation of the surface runoff susceptibility maps. The method is applied in the Lézarde catchment (210 km2, northern France) and the susceptibility maps are evaluated by comparison with two risk regulatory zonings of surface runoff and soil erosion, and two databases of surface runoff impacts on roads and railways. Comparison tests are performed using a standard verification method for dichotomous forecasting along with five verification indicators: accuracy, bias, success ratio, probability of detection, and false alarm ratio. The evaluation shows that the susceptibility map of surface runoff accumulation is able to identify the concentrated surface runoff flows and that the susceptibility map of transfer is able to identify areas that are susceptible to soil erosion. Concerning the ability of the IRIP method to detect sections of the transportation network susceptible to be impacted by surface runoff, the evaluation tests show promising probabilities of detection (73-90%) but also high false alarm ratios (77-92%). However, a qualitative analysis of the local configuration of the infrastructure shows that taking into account the transportation network vulnerability can explain numerous false alarms. This paper shows that the

  5. Surface-Constrained Volumetric Brain Registration Using Harmonic Mappings

    PubMed Central

    Joshi, Anand A.; Shattuck, David W.; Thompson, Paul M.; Leahy, Richard M.

    2015-01-01

    In order to compare anatomical and functional brain imaging data across subjects, the images must first be registered to a common coordinate system in which anatomical features are aligned. Intensity-based volume registration methods can align subcortical structures well, but the variability in sulcal folding patterns typically results in misalignment of the cortical surface. Conversely, surface-based registration using sulcal features can produce excellent cortical alignment but the mapping between brains is restricted to the cortical surface. Here we describe a method for volumetric registration that also produces an accurate one-to-one point correspondence between cortical surfaces. This is achieved by first parameterizing and aligning the cortical surfaces using sulcal landmarks. We then use a constrained harmonic mapping to extend this surface correspondence to the entire cortical volume. Finally, this mapping is refined using an intensity-based warp. We demonstrate the utility of the method by applying it to T1-weighted magnetic resonance images (MRI). We evaluate the performance of our proposed method relative to existing methods that use only intensity information; for this comparison we compute the inter-subject alignment of expert-labeled sub-cortical structures after registration. PMID:18092736

  6. 43 CFR 3931.60 - Maps of underground and surface mine workings and in situ surface operations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Maps of underground and surface mine....60 Maps of underground and surface mine workings and in situ surface operations. Maps of underground workings and surface operations must be to a scale of 1:24,000 or larger if the BLM requests it. All...

  7. Mapping surface charge density of lipid bilayers by quantitative surface conductivity microscopy

    NASA Astrophysics Data System (ADS)

    Klausen, Lasse Hyldgaard; Fuhs, Thomas; Dong, Mingdong

    2016-08-01

    Local surface charge density of lipid membranes influences membrane-protein interactions leading to distinct functions in all living cells, and it is a vital parameter in understanding membrane-binding mechanisms, liposome design and drug delivery. Despite the significance, no method has so far been capable of mapping surface charge densities under physiologically relevant conditions. Here, we use a scanning nanopipette setup (scanning ion-conductance microscope) combined with a novel algorithm to investigate the surface conductivity near supported lipid bilayers, and we present a new approach, quantitative surface conductivity microscopy (QSCM), capable of mapping surface charge density with high-quantitative precision and nanoscale resolution. The method is validated through an extensive theoretical analysis of the ionic current at the nanopipette tip, and we demonstrate the capacity of QSCM by mapping the surface charge density of model cationic, anionic and zwitterionic lipids with results accurately matching theoretical values.

  8. Mapping surface charge density of lipid bilayers by quantitative surface conductivity microscopy

    PubMed Central

    Klausen, Lasse Hyldgaard; Fuhs, Thomas; Dong, Mingdong

    2016-01-01

    Local surface charge density of lipid membranes influences membrane–protein interactions leading to distinct functions in all living cells, and it is a vital parameter in understanding membrane-binding mechanisms, liposome design and drug delivery. Despite the significance, no method has so far been capable of mapping surface charge densities under physiologically relevant conditions. Here, we use a scanning nanopipette setup (scanning ion-conductance microscope) combined with a novel algorithm to investigate the surface conductivity near supported lipid bilayers, and we present a new approach, quantitative surface conductivity microscopy (QSCM), capable of mapping surface charge density with high-quantitative precision and nanoscale resolution. The method is validated through an extensive theoretical analysis of the ionic current at the nanopipette tip, and we demonstrate the capacity of QSCM by mapping the surface charge density of model cationic, anionic and zwitterionic lipids with results accurately matching theoretical values. PMID:27561322

  9. [Dobutamine stress body surface mapping in Kawasaki disease].

    PubMed

    Seki, T; Zhang, J; Ogawa, S; Hirayama, T

    1994-11-01

    The dobutamine (DOB) stress body surface mapping tests were carried out to detect myocardial ischemia in 23 patients who had Kawasaki disease previously. Eight of 23 patients (group A) had coronary stenosis of 75% or more diameter reduction in major coronary arteries without sufficient collateral flow, as shown by the coronary angiography, but without myocardial infarction. Nine patients (group B) showed no ischemic change exercised 201Tl myocardial scintigram. Six patients (group C) had myocardial infarction due to Kawasaki disease. ST segment potential mapping (0.04 sec after the J point in QRS) and ST-T Isointegral mapping were performed using CVM-3000 system (87 leads), and the following calculations were made: number of leads with horizontal or down-sloping ST depression of 0.10 mV or more, lasting 0.08 sec (nST); row number of the minimum lead in the Isointegral map (Imin); number of positive leads on the seventh row in Isointegral mapping (I-7); number of positive leads on the first row in Isointegral mapping (I-1) and I-7/I-1 ratio. Based on these calculations the criteria for detecting myocardial ischemia (nST < or = 2, Imin < or = 2, I-7/I-1 > or = 1) were created and their usefulness was tested using findings of coronary angiography and exercised 201Tl myocardial scintigram as the golden standard. For the diagnosis of ischemic lesion, the DOB stress body surface mapping test in group A had higher specificity (nST: 100%, Imin: 89%, I-7/I-1: 100% vs. 78%) and higher sensitivity (75%, 50%, 63% vs. 38%), than those by the Treadmill test, while ischemic changes were not detected in group C by this test. From these results it is concluded that it is useful in evaluating ischemic heart disease in children who can not perform Treadmill exercised test adequately.

  10. 43 CFR 3592.2 - Maps of underground workings and surface operations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Maps of underground workings and surface... THAN COAL) EXPLORATION AND MINING OPERATIONS Plans and Maps § 3592.2 Maps of underground workings and surface operations. Maps of underground workings and surface operations shall be drawn to a...

  11. 43 CFR 3592.2 - Maps of underground workings and surface operations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Maps of underground workings and surface... THAN COAL) EXPLORATION AND MINING OPERATIONS Plans and Maps § 3592.2 Maps of underground workings and surface operations. Maps of underground workings and surface operations shall be drawn to a...

  12. 43 CFR 3592.2 - Maps of underground workings and surface operations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Maps of underground workings and surface... THAN COAL) EXPLORATION AND MINING OPERATIONS Plans and Maps § 3592.2 Maps of underground workings and surface operations. Maps of underground workings and surface operations shall be drawn to a...

  13. 43 CFR 3592.2 - Maps of underground workings and surface operations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Maps of underground workings and surface... THAN COAL) EXPLORATION AND MINING OPERATIONS Plans and Maps § 3592.2 Maps of underground workings and surface operations. Maps of underground workings and surface operations shall be drawn to a...

  14. Mapping vibrational surface and bulk modes in a single nanocube

    NASA Astrophysics Data System (ADS)

    Lagos, Maureen J.; Trügler, Andreas; Hohenester, Ulrich; Batson, Philip E.

    2017-03-01

    Imaging of vibrational excitations in and near nanostructures is essential for developing low-loss infrared nanophotonics, controlling heat transport in thermal nanodevices, inventing new thermoelectric materials and understanding nanoscale energy transport. Spatially resolved electron energy loss spectroscopy has previously been used to image plasmonic behaviour in nanostructures in an electron microscope, but hitherto it has not been possible to map vibrational modes directly in a single nanostructure, limiting our understanding of phonon coupling with photons and plasmons. Here we present spatial mapping of optical and acoustic, bulk and surface vibrational modes in magnesium oxide nanocubes using an atom-wide electron beam. We find that the energy and the symmetry of the surface polariton phonon modes depend on the size of the nanocubes, and that they are localized to the surfaces of the nanocube. We also observe a limiting of bulk phonon scattering in the presence of surface phonon modes. Most phonon spectroscopies are selectively sensitive to either surface or bulk excitations; therefore, by demonstrating the excitation of both bulk and surface vibrational modes using a single probe, our work represents advances in the detection and visualization of spatially confined surface and bulk phonons in nanostructures.

  15. Mapping vibrational surface and bulk modes in a single nanocube.

    PubMed

    Lagos, Maureen J; Trügler, Andreas; Hohenester, Ulrich; Batson, Philip E

    2017-03-22

    Imaging of vibrational excitations in and near nanostructures is essential for developing low-loss infrared nanophotonics, controlling heat transport in thermal nanodevices, inventing new thermoelectric materials and understanding nanoscale energy transport. Spatially resolved electron energy loss spectroscopy has previously been used to image plasmonic behaviour in nanostructures in an electron microscope, but hitherto it has not been possible to map vibrational modes directly in a single nanostructure, limiting our understanding of phonon coupling with photons and plasmons. Here we present spatial mapping of optical and acoustic, bulk and surface vibrational modes in magnesium oxide nanocubes using an atom-wide electron beam. We find that the energy and the symmetry of the surface polariton phonon modes depend on the size of the nanocubes, and that they are localized to the surfaces of the nanocube. We also observe a limiting of bulk phonon scattering in the presence of surface phonon modes. Most phonon spectroscopies are selectively sensitive to either surface or bulk excitations; therefore, by demonstrating the excitation of both bulk and surface vibrational modes using a single probe, our work represents advances in the detection and visualization of spatially confined surface and bulk phonons in nanostructures.

  16. Efficient epitope mapping by bacteriophage {lambda} surface display

    SciTech Connect

    Kuwabara, I.; Maruyama, H.; Zuberi, R.I.

    1997-01-01

    A bacteriophage {lambda} surface expression system, {lambda}foo, was used for epitope mapping of human galectin-3. We constructed random epitope and peptide libraries and compared their efficiencies in the mapping. The galectin-3 cDNA was randomly digested by DNase I to make random epitope libraries. The libraries were screened by affinity selection using a microtiter plate coated with monoclonal antibodies. Direct DNA sequencing of the selected clones defined two distinct epitope sites consisting of nine and 11 amino-acid residues. Affinity selection of random peptide libraries recovered a number of sequences that were similar to each other but distinct from the galectin-3 sequence. These results demonstrate that a single affinity selection of epitope libraries with antibodies is able to define an epitope determinant as small as nine residues long and is more efficient in epitope mapping than random peptide libraries. 25 refs., 4 figs., 1 tab.

  17. Phased-array ultrasonic surface contour mapping system. Technical note

    SciTech Connect

    Fasching, G.E.; Loudin, W.J.; Paton, D.E.; Smith, N.S. Jr.

    1992-11-01

    The development of reliable mechanistic models for prediction of conventional and fluidized-bed combustor and gasifier operation and solids flow behavior in silos or other solids handling and storage components requires knowledge of the contained solids flow characteristics. This knowledge is gained from dynamic experimental measurements of bed top surface contours in addition to measurements of bulk bed properties. The surface contour mapping system (SCMS) provides a means of generating surface contour maps in real time with a unique, automatically focused, density-compensated, digital phased-array scanning, ultrasonic-range measurement system. The system is designed to operate in environments having gas temperatures up to 1,600 {degree}F and pressures to 1,000 psig. Computer simulation of several SCMS candidates and acoustic carrier modulation techniques indicates that a surface measurement resolution of {plus_minus}2 inches over a range of 5 to 20 feet distance between the transmit/receive (T/R) transducers and the bed surface can be expected. The simulation of a particular design, a 9-T/R, 25-pixel bed surface, in which the level of each pixel was randomly set between 5 and 7 feet below the plane of the T/R transducers, then measured using two different modulation techniques, produced excellent results. The simulation of this surface contour mapping system determined the value of the level of each of the 25 pixels to within {plus_minus}1 inch for over 95 percent of more than 100 test cases for one of the modulation techniques, and for over 99 percent of about 100 test cases for a second modulation technique. A hardware implementation of the design simulated but using only a two-T/R, three-pixel SCMS produced results very closely approximating those obtained during the simulation.

  18. Mapping cell surface adhesion by rotation tracking and adhesion footprinting

    NASA Astrophysics Data System (ADS)

    Li, Isaac T. S.; Ha, Taekjip; Chemla, Yann R.

    2017-03-01

    Rolling adhesion, in which cells passively roll along surfaces under shear flow, is a critical process involved in inflammatory responses and cancer metastasis. Surface adhesion properties regulated by adhesion receptors and membrane tethers are critical in understanding cell rolling behavior. Locally, adhesion molecules are distributed at the tips of membrane tethers. However, how functional adhesion properties are globally distributed on the individual cell’s surface is unknown. Here, we developed a label-free technique to determine the spatial distribution of adhesive properties on rolling cell surfaces. Using dark-field imaging and particle tracking, we extract the rotational motion of individual rolling cells. The rotational information allows us to construct an adhesion map along the contact circumference of a single cell. To complement this approach, we also developed a fluorescent adhesion footprint assay to record the molecular adhesion events from cell rolling. Applying the combination of the two methods on human promyelocytic leukemia cells, our results surprisingly reveal that adhesion is non-uniformly distributed in patches on the cell surfaces. Our label-free adhesion mapping methods are applicable to the variety of cell types that undergo rolling adhesion and provide a quantitative picture of cell surface adhesion at the functional and molecular level.

  19. Mapping cell surface adhesion by rotation tracking and adhesion footprinting

    PubMed Central

    Li, Isaac T. S.; Ha, Taekjip; Chemla, Yann R.

    2017-01-01

    Rolling adhesion, in which cells passively roll along surfaces under shear flow, is a critical process involved in inflammatory responses and cancer metastasis. Surface adhesion properties regulated by adhesion receptors and membrane tethers are critical in understanding cell rolling behavior. Locally, adhesion molecules are distributed at the tips of membrane tethers. However, how functional adhesion properties are globally distributed on the individual cell’s surface is unknown. Here, we developed a label-free technique to determine the spatial distribution of adhesive properties on rolling cell surfaces. Using dark-field imaging and particle tracking, we extract the rotational motion of individual rolling cells. The rotational information allows us to construct an adhesion map along the contact circumference of a single cell. To complement this approach, we also developed a fluorescent adhesion footprint assay to record the molecular adhesion events from cell rolling. Applying the combination of the two methods on human promyelocytic leukemia cells, our results surprisingly reveal that adhesion is non-uniformly distributed in patches on the cell surfaces. Our label-free adhesion mapping methods are applicable to the variety of cell types that undergo rolling adhesion and provide a quantitative picture of cell surface adhesion at the functional and molecular level. PMID:28290531

  20. Mapping of an approximate neutral density surface with Ungridded data

    NASA Astrophysics Data System (ADS)

    You, Yuzhu

    2008-02-01

    A neutral density surface is a logical study frame for water-mass mixing since water parcels spread along such a surface without doing work against buoyancy restoring force. Mesoscale eddies are believed to stir and subsequently mix predominantly along such surfaces. Because of the nonlinear nature of the equation of state of seawater, the process of accurately mapping a neutral density surface necessarily involves lateral computation from one conductivity, temperature and depth (CTD) cast to the next in a logical sequence. By contrast, the depth of a potential density surface on any CTD cast is found solely from the data on this cast. The lateral calculation procedure causes a significant inconvenience. In a previous paper by present author published in this journal (You, 2006), the mapping of neutral density surfaces with regularly gridded data such as Levitus data has been introduced. In this note, I present a new method to find the depth of a neutral density surface from a cast without having to specify an integration path in space. An appropriate reference point is required that is on the neutral density surface and thereafter the neutral density surface can be determined by using the CTD casts in any order. This method is only approximate and the likely errors can be estimated by plotting a scatter diagram of all the pressures and potential temperatures on the neutral density surfaces. The method assumes that the variations of potential temperature and pressure (with respect to the values at the reference point) on the neutral density surface are proportional. It is important to select the most appropriate reference point in order to approximately satisfy this assumption, and in practice this is found by inspecting the θ-p plot of data on the surface. This may require that the algorithm be used twice. When the straight lines on the θ-p plot, drawn from the reference point to other points on the neutral density surface, enclose an area that is external to

  1. Dynamic Corneal Surface Mapping with Electronic Speckle Pattern Interferometry

    NASA Astrophysics Data System (ADS)

    Iqbal, S.; Gualini, M. M. S.

    2013-06-01

    In view of the fast advancement in ophthalmic technology and corneal surgery, there is a strong need for the comprehensive mapping and characterization techniques for corneal surface. Optical methods with precision non-contact approaches have been found to be very useful for such bio measurements. Along with the normal mapping approaches, elasticity of corneal surface has an important role in its characterization and needs to be appropriately measured or estimated for broader diagnostics and better prospective surgical results, as it has important role in the post-op corneal surface reconstruction process. Use of normal corneal topographic devices is insufficient for any intricate analysis since these devices operate at relatively moderate resolution. In the given experiment, Pulsed Electronic Speckle Pattern Interferometry has been utilized along with an excitation mechanism to measure the dynamic response of the sample cornea. A Pulsed ESPI device has been chosen for the study because of its micron-level resolution and other advantages in real-time deformation analysis. A bovine cornea has been used as a sample in the subject experiment. The dynamic response has been taken on a chart recorder and it is observed that it does show a marked deformation at a specific excitation frequency, which may be taken as a characteristic elasticity parameter for the surface of that corneal sample. It was seen that outside resonance conditions the bovine cornea was not that much deformed. Through this study, the resonance frequency and the corresponding corneal deformations are mapped and plotted in real time. In these experiments, data was acquired and processed by FRAMES plus computer analysis system. With some analysis of the results, this technique can help us to refine a more detailed corneal surface mathematical model and some preliminary work was done on this. Such modelling enhancements may be useful for finer ablative surgery planning. After further experimentation

  2. Probing and mapping electrode surfaces in solid oxide fuel cells.

    PubMed

    Blinn, Kevin S; Li, Xiaxi; Liu, Mingfei; Bottomley, Lawrence A; Liu, Meilin

    2012-09-20

    Solid oxide fuel cells (SOFCs) are potentially the most efficient and cost-effective solution to utilization of a wide variety of fuels beyond hydrogen (1-7). The performance of SOFCs and the rates of many chemical and energy transformation processes in energy storage and conversion devices in general are limited primarily by charge and mass transfer along electrode surfaces and across interfaces. Unfortunately, the mechanistic understanding of these processes is still lacking, due largely to the difficulty of characterizing these processes under in situ conditions. This knowledge gap is a chief obstacle to SOFC commercialization. The development of tools for probing and mapping surface chemistries relevant to electrode reactions is vital to unraveling the mechanisms of surface processes and to achieving rational design of new electrode materials for more efficient energy storage and conversion(2). Among the relatively few in situ surface analysis methods, Raman spectroscopy can be performed even with high temperatures and harsh atmospheres, making it ideal for characterizing chemical processes relevant to SOFC anode performance and degradation(8-12). It can also be used alongside electrochemical measurements, potentially allowing direct correlation of electrochemistry to surface chemistry in an operating cell. Proper in situ Raman mapping measurements would be useful for pin-pointing important anode reaction mechanisms because of its sensitivity to the relevant species, including anode performance degradation through carbon deposition(8, 10, 13, 14) ("coking") and sulfur poisoning(11, 15) and the manner in which surface modifications stave off this degradation(16). The current work demonstrates significant progress towards this capability. In addition, the family of scanning probe microscopy (SPM) techniques provides a special approach to interrogate the electrode surface with nanoscale resolution. Besides the surface topography that is routinely collected by AFM

  3. Mapping permeability over the surface of the Earth

    USGS Publications Warehouse

    Gleeson, T.; Smith, L.; Moosdorf, N.; Hartmann, J.; Durr, H.H.; Manning, A.H.; Van Beek, L. P. H.; Jellinek, A. Mark

    2011-01-01

    Permeability, the ease of fluid flow through porous rocks and soils, is a fundamental but often poorly quantified component in the analysis of regional-scale water fluxes. Permeability is difficult to quantify because it varies over more than 13 orders of magnitude and is heterogeneous and dependent on flow direction. Indeed, at the regional scale, maps of permeability only exist for soil to depths of 1-2 m. Here we use an extensive compilation of results from hydrogeologic models to show that regional-scale (>5 km) permeability of consolidated and unconsolidated geologic units below soil horizons (hydrolithologies) can be characterized in a statistically meaningful way. The representative permeabilities of these hydrolithologies are used to map the distribution of near-surface (on the order of 100 m depth) permeability globally and over North America. The distribution of each hydrolithology is generally scale independent. The near-surface mean permeability is of the order of ???5 ?? 10-14 m2. The results provide the first global picture of near-surface permeability and will be of particular value for evaluating global water resources and modeling the influence of climate-surface-subsurface interactions on global climate change. Copyright ?? 2011 by the American Geophysical Union.

  4. Mapping permeability over the surface of the Earth

    USGS Publications Warehouse

    Gleeson, Tom; Smith, Leslie; Moosdorf, Nils; Hartmann, Jens; Durr, Hans H.; Manning, Andrew H.; van Beek, Ludovicus P. H.; Jellinek, A. Mark

    2011-01-01

    Permeability, the ease of fluid flow through porous rocks and soils, is a fundamental but often poorly quantified component in the analysis of regional-scale water fluxes. Permeability is difficult to quantify because it varies over more than 13 orders of magnitude and is heterogeneous and dependent on flow direction. Indeed, at the regional scale, maps of permeability only exist for soil to depths of 1-2 m. Here we use an extensive compilation of results from hydrogeologic models to show that regional-scale (>5 km) permeability of consolidated and unconsolidated geologic units below soil horizons (hydrolithologies) can be characterized in a statistically meaningful way. The representative permeabilities of these hydrolithologies are used to map the distribution of near-surface (on the order of 100 m depth) permeability globally and over North America. The distribution of each hydrolithology is generally scale independent. The near-surface mean permeability is of the order of -5 x 10-14 m2. The results provide the first global picture of near-surface permeability and will be of particular value for evaluating global water resources and modeling the influence of climate-surface-subsurface interactions on global climate change.

  5. Mapping charge-mosaic surfaces in electrolyte solutions using surface charge microscopy

    NASA Astrophysics Data System (ADS)

    Drelich, Jaroslaw; Yin, Xihui

    2010-06-01

    A significant limitation of electrokinetic measurements is that only an average value of the zeta potential/streaming potential is measured—regardless of whether the surface charge distribution is homogeneous or otherwise. However, in real-world situations, nearly all solids (and liquids) of technological significance exhibit surface heterogeneities. To detect heterogeneities in surface charge, analytical tools which provide accurate and spatially resolved information about material surface potential—particularly at microscopic and sub-microscopic resolutions—are needed. A novel AFM-based technique for mapping surface charge domains on heterogeneous surfaces, which we call Surface Charge Microscopy ( SCM), was recently introduced by our research team. It relies on recording colloidal force curves over multiple locations on the substrate surface using small probes. The surface charge characteristics of the heterogeneous substrate are determined from the recorded colloidal force curves, allowing for the surface charge variation to be mapped. In this communication, we briefly review the SCM technique. Examples of results of measurements of the surface interaction forces that were recorded between a silicon nitride AFM cantilever and a multi-phase volcanic rock and heterogeneous surface of bitumen are also given.

  6. Identifying and Mapping Seasonal Surface Water Frost with MGS TES

    NASA Astrophysics Data System (ADS)

    Bapst, J.; Bandfield, J. L.; Wood, S. E.

    2013-12-01

    The Thermal Emission Spectrometer (TES) visible/near-infrared and thermal infrared bolometers measured surface broadband albedo and temperature for more than three Mars years. As seasons progress on Mars, surface temperatures may fall below the frost point of volatiles in the atmosphere (namely, carbon dioxide and water). Systematic mapping of the spatial and temporal occurrence of these volatiles in the martian atmosphere, on the surface, and in the subsurface has shown their importance in understanding the climate of Mars. However, few studies have investigated seasonal surface water frost and its role in the global water cycle. We examine zonally-averaged TES daytime albedo, temperature, and water vapor abundance data [after Smith, 2004] to map the presence of surface water frost on Mars. Surface water frost occurs in the polar and mid latitudes, in regions with surface temperatures less than 220 K and above 150 K, and can significantly increase albedo relative to the bare surface. In the northern hemisphere water frost is most apparent in late fall/early winter, before the onset of carbon dioxide frost. Dust storms occurring near northern winter solstice affect albedo data and prevent us from putting a latitudinal lower limit on the water frost in the northern hemisphere. Regardless, seasonal water frost occurs at least as low as 48°N in Utopia Planitia, beginning at Ls=~230°, as observed by Viking Lander 2 [Svitek and Murray, 1990]. Daytime surface water frost was also observed at the Phoenix Lander site (68°N) beginning at Ls=~160° [Cull et al., 2010]. The timing of albedo variations observed by TES agree relatively well with lander observations of seasonal frost. Seasonal water frost is not detected during fall in the southern hemisphere. A potential explanation for this discrepancy, compared with frost detections in the north, is the disparity in atmospheric water vapor abundance between the two hemispheres. The frost point temperatures for water vapor

  7. Surface Photometry of Reverberation-Mapped Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Bower, Gary A.

    2015-01-01

    I present a statistical analysis of the surface photometry obtained for a sample of Hubble Space Telescope (HST) archival images of the host galaxies containing active galactic nuclei (AGN), whose time-delay between continuum and broad emission line variations have been analyzed (i.e., reverberation mapping). For quiescent galaxies, strong correlations exist between central black hole mass and host galaxy structure. If there are similar correlations for AGN between central black hole masses derived from reverberation mapping and the host galaxy structure that I have derived from archival HST images, this would imply some validation of the assumptions underlying reverberation mapping concerning the structure, kinematics, and orientation of the broad line regions in AGN.The correlations for quiescent galaxies bewteen central black hole mass and host galaxy structure imply that there might be a strong causal connection between the formation and evolution of the black hole and the galaxy bulge. A current hypothesis is that bulges, black holes, and quasars formed, grew, or turned on as parts of the same process, in part because the collapse or merger of bulges might provide a rich fuel supply to a central black hole. One way of testing this hypothesis would be to plot AGN as a function of redshift on these correlations. However, two severe obstacles limit the ability to measure black hole masses in AGN using HST to analyze the central stellar and/or gas dynamics: (1) since spatial resolution becomes more limited at larger distances, only two reverberation-mapped AGN are close enough to Earth to render the analysis feasible, and (2) it isdifficult to obtain useful spectra of the stars and/or gas in the presence of the bright nonstellar nucleus. The most useful alternative is to exploit reverberation mapping, which uses the time delay in a given AGN between variations in the continuum emission and broad emission lines.

  8. Quantitative surface parameter maps using Intermodulation Atomic Force Microscopy

    NASA Astrophysics Data System (ADS)

    Forchheimer, Daniel; Platz, Daniel; Tholén, Erik; Hutter, Carsten; Haviland, David

    2011-03-01

    It is well known that the phase image in amplitude modulation atomic force microscopy (AM-AFM) is sensitive to material properties of the surface. However that information is not enough to fully quantify the tip-surface interaction. We have developed Intermodulation AFM, based on a spectral analysis of the cantilever's nonlinear dynamics, which increases the amount of information obtained without increasing scan time. We show how it is possible to extract quantitative material properties of the surface from this additional information. The method works under the assumption of a tip-surface force model, such as the DMT model, fitting the model parameters to the measured spectral data. The parameters are obtained at each pixel of the AFM image and form surface property maps which can be displayed together with topography. We demonstrate this on different surfaces such as polymer blends, extracting stiffness and adhesive properties. D. Platz, E. A. Tholen, D. Pesen, and D. B. Haviland, Appl. Phys. Lett., 92, 153106 (2008)

  9. Mapping of plume deposits and surface composition on Enceladus

    NASA Astrophysics Data System (ADS)

    Nordheim, T. A.; Scipioni, F.; Cruikshank, D. P.; Clark, R. N.,; Hand, K. P.

    2017-01-01

    A major result of the Cassini mission was the discovery that the small mid-sized moon Enceladus is presently geological active[Dougherty et al., 2006; Porco et al., 2006; Spencer et al., 2006; Hansen et al., 2008]. This activity results in plumes of water vapor and ice emanating from a series of fractures ("Tiger Stripes") at the moon's South Pole. Some fraction of plume material escapes the moon's gravity and populates the E-ring as well as ultimately providing a source of fresh plasma in the Saturnian magnetosphere [Pontius and Hill, 2006; Kempf et al., 2010]. However, a significant portion of plume material is redeposited on Enceladus and thus provides a source of surface contaminants. By studying the near-infrared spectral signatures of these contaminants we may put new constraints on the composition of the plumes and, ultimately, their source, which is currently believed to be Enceladus's global sub-surface ocean [Iess et al., 2014]. Here we present preliminary results from our analysis of observations from the Visual and Infrared Mapping Spectrometer (VIMS) [Brown et al., 2005] onboard Cassini and mapping of plume deposits across the surface of Enceladus. We have investigated the global variation of the water ice Fresnel peak at 3.1 μm, which may be used as an indicator of ice crystallinity [Hansen & McCord, 2004; Jaumann et al., 2008; Newman et al., 2008]. We have also investigated the slope of the 1.11-2.25 μm spectral region, which serves as an indicator of water ice grain size for small grains (< 100 μm) as well as the presence of contaminants [e.g. Filacchione et al., 2010]. Finally, we have identified and mapped an absorption feature centered at 3.25 μm that may be related to organic contaminants, represented by the band depth of the fundamental C-H stretch [e.g. Cruikshank et al., 2014; Scipioni et al., 2014].

  10. Mapping the global land surface using 1 km AVHRR data

    USGS Publications Warehouse

    Lauer, D.T.; Eidenshink, J.C.

    1998-01-01

    The scientific requirements for mapping the global land surface using 1 km advanced very high resolution radiometer (AVHRR) data have been set forth by the U.S. Global Change Research Program; the International Geosphere Biosphere Programme (IGBP); The United Nations; the National Oceanic and Atmospheric Administration (NOAA); the Committee on Earth Observations Satellites; and the National Aeronautics and Space Administration (NASA) mission to planet Earth (MTPE) program. Mapping the global land surface using 1 km AVHRR data is an international effort to acquire, archive, process, and distribute 1 km AVHRR data to meet the needs of the international science community. A network of AVHRR receiving stations, along with data recorded by NOAA, has been acquiring daily global land coverage since April 1, 1992. A data set of over 70,000 AVHRR images is archived and distributed by the United States Geological Survey (USGS) EROS Data Center, and the European Space Agency. Under the guidance of the IGBP, processing standards have been developed for calibration, atmospheric correction, geometric registration, and the production of global 10-day maximum normalized difference vegetation index (NDVI) composites. The major uses of the composites are for the study of surface vegetation condition, mapping land cover, and deriving biophysical characteristics of terrestrial ecosystems. A time-series of 54 10-day global vegetation index composites for the period of April 1, 1992 through September 1993 has been produced. The production of a time-series of 33 10-day global vegetation index composites using NOAA-14 data for the period of February 1, 1995 through December 31, 1995 is underway. The data products are available from the USGS, in cooperation with NASA's MTPE program and other international organizations.

  11. Surface plasmon resonance imaging by holographic enhanced mapping.

    PubMed

    Mandracchia, B; Pagliarulo, V; Paturzo, M; Ferraro, P

    2015-04-21

    We designed, constructed and tested a holographic surface plasmon resonance (HoloSPR) objective-based microscope for simultaneous amplitude-contrast and phase-contrast surface plasmon resonance imaging (SPRi). SPRi is a widely spread tool for label-free detection of changes in refractive index and concentration, as well as mapping of thin films. Currently, most of the SPR sensors rely on the detection of amplitude or phase changes of light. Despite the high sensitivities achieved so far, each technique alone has a limited detection range with optimal sensitivity. Here we use a high numerical aperture objective that avoids all the limitations due to the use of a prism-based configuration, yielding highly magnified and distortion-free images. Holographic reconstructions of SPR images and real-time kinetic measurements are presented to show the capability of HoloSPR to provide a versatile imaging method for high-throughput SPR detection complementary to conventional SPR techniques.

  12. Rapid Mapping of Surface Rupture from the South Napa Earthquake

    NASA Astrophysics Data System (ADS)

    Trexler, C. C.; Morelan, A. E., III; Oskin, M. E.

    2014-12-01

    Rapid documentation (<1 day) of co-seismic surface rupture location and slip is essential for scientific and emergency response. We demonstrate how social media (text messaging and Twitter) and the emerging 3D data collection technique known as Structure from Motion (SfM), used in conjunction with traditional field reconnaissance, enabled us to rapidly locate and document surface ruptures from the Mw 6.0 South Napa earthquake. On the morning of the event, our field team used information available on social media to identify locations with potential surface rupture. Preliminary observations of surface rupture (measurements and geo-tagged photographs) were texted to the office-based team member who created digital maps of the rupture trace and shared them online via Twitter in near-real time. We documented many ephemeral features (such as offset roads, curbs, and driveways) along the rupture trace within 12 hours of the event, before these features were destroyed by road and infrastructure repair. We were able to return to most sites again within several days, allowing us to document continuing slip and create time-series datasets of offset features. After the collection and re-collection of data at selected sites, we made detailed measurements remotely using 3D models constructed with SfM. The ability to quantitatively project features into the fault plane using these models allows for accurate measurements of small features often difficult to observe and quantify in the field. Traditionally, even preliminary maps of rupture extent and offset magnitudes are not available for several days after an event because office-based processing and compilation is required. Because we were able to compile our data in real time, we distributed our results while they were still valuable for ongoing scientific response. Our work helped other science teams efficiently target fieldwork and instrument deployment; for example, one geodetic survey team used our surface rupture map to

  13. SMOS sea surface salinity maps of the Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Gabarro, Carolina; Olmedo, Estrella; Turiel, Antonio; Ballabrera-Poy, Joaquim; Martinez, Justino; Portabella, Marcos

    2016-04-01

    Salinity and temperature gradients drive the thermohaline circulation of the oceans, and play a key role in the ocean-atmosphere coupling. The strong and direct interactions between the ocean and the cryosphere (primarily through sea ice and ice shelves) is also a key ingredient of the thermohaline circulation. The ESA's Soil Moisture and Ocean Salinity (SMOS) mission, launched in 2009, has the objective measuring soil moisture over the continents and sea surface salinity over the oceans. Although the mission was originally conceived for hydrological and oceanographic studies [1], SMOS is also making inroads in the cryospheric monitoring. SMOS carries an innovative L-band (1.4 GHz, or 21-cm wavelength), passive interferometric radiometer (the so-called MIRAS) that measures the electromagnetic radiation emitted by the Earth's surface, at about 50 km spatial resolution wide swath (1200-km), and with a 3-day revisit time at the equator, but a more frequent one at the poles. Although the SMOS radiometer operating frequency offers almost the maximum sensitivity of the brightness temperature (TB) to sea surface salinity (SSS) variations, this is rather low, , i.e.,: 90% of ocean SSS values span a range of brightness temperatures of only 5K at L-band. This sensitivity is particularly low in cold waters. This implies that the SSS retrieval requires high radiometric performance. Since the SMOS launch, SSS Level 3 maps have been distributed by several expert laboratories including the Barcelona Expert Centre (BEC). However, since the TB sensitivity to SSS decreases with decreasing sea surface temperature (SST), large retrieval errors had been reported when retrieving salinity values at latitudes above 50⁰N. Two new processing algorithms, recently developed at BEC, have led to a considerable improvement of the SMOS data, allowing for the first time to derive SSS maps in cold waters. The first one is to empirically characterize and correct the systematic biases with six

  14. Raman mapping of intact biofilms on stainless steel surfaces

    NASA Astrophysics Data System (ADS)

    Nguyen, Julie K.; Heighton, Lynne; Xu, Yunfeng; Nou, Xiangwu; Schmidt, Walter F.

    2016-05-01

    Many issues occur when microbial bacteria contaminates human food or water; it can be dangerous to the public. Determining how the microbial are growing, it can help experts determine how to prevent the outbreaks. Biofilms are a tightly group of microbial cells that grow on living surfaces or surrounding themselves. Though biofilms are not necessarily uniform; when there are more than one type of microbial bacteria that are grown, Raman mapping is performed to determine the growth patterns. Depending on the type of microbial bacteria, they can grow in various patterns such as symmetrical or scattered on the surface. The biofilms need to be intact in order to preclude and potentially figuring out the relative intensity of different components in a biofilm mixture. In addition, it is important to determine whether one biofilms is a substrate for another biofilm to be detected. For example, it is possible if layer B appears above layer A, but layer A doesn't appear above layer B. In this case, three types of biofilms that are grown includes Listeria(L), Ralstonia(R), and a mixture of the two (LR). Since microbe deposits on metal surfaces are quite suitable, biofilms were grown on stainless steel surface slides. Each slide was viewed under a Raman Microscope at 100X and using a 532nm laser to provide great results and sharp peaks. The mapping of the laser helps determine how the bacteria growth, at which intensity the bacteria appeared in order to identify specific microbes to signature markers on biofilms.

  15. CosmoQuest: A software platform for surface feature mapping

    NASA Astrophysics Data System (ADS)

    Gay, Pamela

    2016-07-01

    While many tools exist for allowing individuals to mark features in images, it has previously been unwieldy to get entire teams collaboratively mapping out surface features, and to statistically compare each team members contributions. Our CSB software was initially developed to facilitate crowd-sourcing projects, including CosmoQuest's "Moon Mappers" project. Statistically study of its results (Robbins et al 2014) has shown that professionals using this software get results that are as good as those they get using other commonly used software packages. This has lead to an expansion of the software to facilitate professional science use of the software. In order to allow the greatest use of CSB, and to facilitate better science collaboration, CosmoQuest now allows teams to create private projects. Basic features include: using their own data sets, allowing multiple team members to annotate the images, performing basic statistics on the resulting data, downloading all results in either .sql or .csv formats. In this presentation, we will overview how best to use CSB to improve your own science collaboration. Current applications include surface science and transient object identification, and published results include both crater maps and the discovery of KBOs.

  16. Surface Towed CSEM Systems for Shallow Water Mapping

    NASA Astrophysics Data System (ADS)

    Sherman, J.; Constable, S.; Kannberg, P. K.

    2015-12-01

    We have developed a low-power, surface towed electric dipole-dipole system suitable for mapping seafloor geology in shallow water and deployable from small boats. The transmitter is capable of up to 50 amps output using 12 VDC from a 110/240 VAC power supply, and can generate an arbitrary GPS stabilized ternary waveform. Transmitter antennas are typically 50 to 100 m long. Receivers are built around the standard Scripps seafloor electrode, amplifier, and logging systems but housed in floating PVC cases and equipped with GPS timing and positioning, pitch/roll/heading sensors, and accelerometers. Receiver dipoles are 1.5 m long rigid booms held 1 m below the surface. As with the Scripps deep-towed Vulcan system, rigid antennas are used to avoid noise associated with flexible antennas moving across Earth's magnetic field. The tow cable is a simple floating rope up to 1000 m long. Water depth and conductivity are sampled continuously in order to provide constraints for apparent resistivity calculations and inversion, and moored seafloor recorders can be used to extend transmitter/receiver offsets. The entire system can be air freighted and transported in one utility vehicle. We will present results from a study to map permafrost in shallow water off Prudhoe Bay, Alaska.

  17. Potentiometric-surface map, 1993, Yucca Mountain and vicinity, Nevada

    SciTech Connect

    Tucci, P.; Burkhardt, D.J.

    1995-12-31

    The revised potentiometric surface map here, using mainly 1993 average water levels, updates earlier maps of this area. Water levels are contoured with 20-m intervals, with additional 0.5-m contours in the small-gradient area SE of Yucca Mountain. Water levels range from 728 m above sea level SE of Yucca to 1,034 m above sea level north of Yucca. Potentiometric levels in the deeper parts of the volcanic rock aquifer range from 730 to 785 m above sea level. The potentiometric surface can be divided into 3 regions: A small gradient area E and SE of Yucca, a moderate-gradient area on the west side of Yucca, and a large-gradient area to the N-NE of Yucca. Water levels from wells at Yucca were examined for yearly trends (1986-93) using linear least-squares regression. Of the 22 wells, three had significant positive trends. The trend in well UE-25 WT-3 may be influenced by monitoring equipment problems. Tends in USW WT-7 and USW WTS-10 are similar; both are located near a fault west of Yucca; however another well near that fault exhibited no significant trend.

  18. Heliospheric current sheet inclinations predicted from source surface maps

    NASA Technical Reports Server (NTRS)

    Shodhan, S.; Crooker, N. U.; Hughes, W. J.; Siscoe, G. L.

    1994-01-01

    The inclinations of the neutral line at the ecliptic plane derived from source surface model maps of coronal fields are measured for the interval from June 1976 to March 1992. The mean and median values of 53 deg and 57 deg are close to the average inclinations determined earlier from minimum variance analyses of solar wind measurements at sector boundaries, but the mode falls in the 80 deg - 90 deg bin. This result, which is based on the model assumptions implicit in deriving the source surface maps, predicts that the heliospheric current sheet typically intersects the ecliptic plane nearly at right angles, even without steepening by stream interaction regions. High inclinations dominate the solar cycle for about 7 years around solar maximum. Dips to lower inclination occur near solar minimum, but high variance admits a wide range of inclinations throughout the cycle. Compared to the smooth solar cycle variation of the maximum latitudinal excursion of the neutral line, often treated as the tilt angle of a flat heliospheric current sheet, the noisy variation of the inclinations reflects the degree to which the neutral line deviates from a sine wave, implying warps and corrugations in the current sheet. About a third of the time the neutral line so deviates that it doubles back in longitude.

  19. Compositional Mapping of the Surfaces of Europa and Ganymede

    NASA Astrophysics Data System (ADS)

    Gruen, Eberhard; Horanyi, M.; Kempf, S.; Krueger, H.; Postberg, F.; Srama, R.; Sternovsky, Z.; Trieloff, M.

    2010-10-01

    The determination of the global surface compositions of Europa and Ganymede is a prime objective of the Europa Jupiter System Mission (EJSM). Classical methods to analyze surfaces of airless planetary objects are IR and gamma ray spectroscopy, and neutron backscatter measurements. Here we present a complementary method to analyze dust particles as samples of planetary objects from which they were released. All airless moons and planets are exposed to the ambient meteoroid bombardment that erodes the surface and generates ejecta particles. The Galileo dust detector (Krueger et al., Icarus, 164, 170, 2003) discovered tenuous ejecta clouds around all Galilean satellites. In-situ mass spectroscopic analysis of these dust particles impacting onto a detector of an orbiting spacecraft reveals their composition. Depending on the altitude from which the dust measurements are taken, the position of origin on the surface can be determined with at least corresponding resolution. Since the detection rates are on the order of thousands per day, spatially resolved maps of the surface composition can be obtained. This `dust spectrometer’ approach provides key chemical and isotopic constraints for varying provinces on the surfaces, leading to better understanding of the body's geological evolution. Traces of mineral or organic components in an ice matrix can be identified and quantified even at low impact speeds >1 km/s. Compositional measurements by the Cassini Cosmic Dust Analyzer of ice grains emitted from Enceladus probed the deep interior of this satellite (Postberg et al., Nature, 459, 1098, 2009). New instrumentation has been developed that meet or exceeded the capabilities in sensitivity and mass resolution of all previous dust analyzers. The deployment of such dust analyzers on the Jupiter Europa Orbiter (JEO) and the Jupiter Ganymede Orbiter (JGO) missions will provide unprecedented information on the surface compositions of these satellites and their potential activity.

  20. Global permittivity mapping of the Martian surface from SHARAD

    NASA Astrophysics Data System (ADS)

    Castaldo, Luigi; Mège, Daniel; Gurgurewicz, Joanna; Orosei, Roberto; Alberti, Giovanni

    2017-03-01

    SHARAD is a subsurface sounding radar aboard NASA's Mars Reconnaissance Orbiter, capable of detecting dielectric discontinuities in the subsurface caused by compositional and/or structural changes. Echoes coming from the surface contain information on geometric properties at metre scale and on the permittivity of the upper layers of the Martian crust. A model has been developed to estimate the effect of surface roughness on echo power, depending on statistical parameters such as RMS height and topothesy. Such model is based on the assumption that topography can be characterized as a self-affine fractal, and its use allows the estimation of the dielectric properties of the first few metres of the Martian soil. A permittivity map of the surface of Mars is obtained, covering several large regions across the planet surface. The most significant correspondence with geology is observed at the dichotomy boundary, with high dielectric constant on the highlands side (7 to over 10) and lower on the lowlands side (3 to 7). Other geological correlations are discussed.

  1. Adhesive force mapping of friction-transferred PTFE film surface

    NASA Astrophysics Data System (ADS)

    Suzuki, H.; Mashiko, S.

    The adhesive force of a friction-transferred polytetrafluoroethylene (PTFE) film was mapped by using an atomic force microscope (AFM) system driven by custom software. The friction-transferred PTFE film, which was made by sliding a PTFE polymer rod on a heated glass, consisted of many PTFE ridges running parallel to the sliding direction on the glass surface. The adhesive force on the sample was derived from force curve measurement. A triangular wave amplified with a custom high-voltage amplifier was fed into the Z piezo of the AFM head through an AFM controller unit to obtain force curves while the AFM cantilever scanned a single line of the sample. The force curves both of the PTFE ridges and of the bare glass surface could be obtained by scanning the region perpendicular to the sliding direction. The deflection signal of the cantilever was sampled and stored in a computer through an AD converter. The adhesive force on the PTFE region was about half that on the glass surface. This difference was explained by the difference in capillary force of the surface water.

  2. Mapping of the ocean surface wind by ocean acoustic interferometers.

    PubMed

    Voronovich, Alexander G; Penland, Cécile

    2011-05-01

    Measurements of marine surface winds are crucial to understanding mechanical and thermodynamic forces on the ocean. Satellite measurements of surface winds provide global coverage but are problematic at high wind speeds. Acoustic techniques of wind speed retrieval, and even for tracking hurricanes, have been suggested as an alternative since wind is a strong source of ambient noise in the ocean. Such approaches involve near-local measurements with bottom-mounted hydrophones located close to the area of interest. This paper suggests a complementary approach: measuring directivity of low-frequency ambient noise in the horizontal plane. These measurements would employ long vertical line arrays (VLAs) spanning a significant portion of the ocean waveguide. Two VLAs separated by a distance of some tens of kilometers and coherently measuring acoustic pressure form a single ocean interferometer. By sampling the area of interest from different perspectives with at least two interferometers, marine surface winds might be mapped over horizontal scales of the order of 1000 km with about 10 km resolution (more specifically, the 10 km resolution here means that contribution from the basis functions representing surface wind field with the scale of spatial variations of the order of 10 km can be resolved; independent retrieval of the wind within 10(4) cells of a corresponding grid is hardly possible). An averaging time required to overcome statistical variability in the noise field is estimated to be about 3 h. Numerical simulations of propagation conditions typical for the North Atlantic Ocean are presented.

  3. Mapping cardiac surface mechanics with structured light imaging

    PubMed Central

    Laughner, Jacob I.; Zhang, Song; Li, Hao; Shao, Connie C.

    2012-01-01

    Cardiovascular disease often manifests as a combination of pathological electrical and structural heart remodeling. The relationship between mechanics and electrophysiology is crucial to our understanding of mechanisms of cardiac arrhythmias and the treatment of cardiac disease. While several technologies exist for describing whole heart electrophysiology, studies of cardiac mechanics are often limited to rhythmic patterns or small sections of tissue. Here, we present a comprehensive system based on ultrafast three-dimensional (3-D) structured light imaging to map surface dynamics of whole heart cardiac motion. Additionally, we introduce a novel nonrigid motion-tracking algorithm based on an isometry-maximizing optimization framework that forms correspondences between consecutive 3-D frames without the use of any fiducial markers. By combining our 3-D imaging system with nonrigid surface registration, we are able to measure cardiac surface mechanics at unprecedented spatial and temporal resolution. In conclusion, we demonstrate accurate cardiac deformation at over 200,000 surface points of a rabbit heart recorded at 200 frames/s and validate our results on highly contrasting heart motions during normal sinus rhythm, ventricular pacing, and ventricular fibrillation. PMID:22796539

  4. Use of models to map potential capture of surface water

    USGS Publications Warehouse

    Leake, Stanley A.

    2006-01-01

    The effects of ground-water withdrawals on surface-water resources and riparian vegetation have become important considerations in water-availability studies. Ground water withdrawn by a well initially comes from storage around the well, but with time can eventually increase inflow to the aquifer and (or) decrease natural outflow from the aquifer. This increased inflow and decreased outflow is referred to as “capture.” For a given time, capture can be expressed as a fraction of withdrawal rate that is accounted for as increased rates of inflow and decreased rates of outflow. The time frames over which capture might occur at different locations commonly are not well understood by resource managers. A ground-water model, however, can be used to map potential capture for areas and times of interest. The maps can help managers visualize the possible timing of capture over large regions. The first step in the procedure to map potential capture is to run a ground-water model in steady-state mode without withdrawals to establish baseline total flow rates at all sources and sinks. The next step is to select a time frame and appropriate withdrawal rate for computing capture. For regional aquifers, time frames of decades to centuries may be appropriate. The model is then run repeatedly in transient mode, each run with one well in a different model cell in an area of interest. Differences in inflow and outflow rates from the baseline conditions for each model run are computed and saved. The differences in individual components are summed and divided by the withdrawal rate to obtain a single capture fraction for each cell. Values are contoured to depict capture fractions for the time of interest. Considerations in carrying out the analysis include use of realistic physical boundaries in the model, understanding the degree of linearity of the model, selection of an appropriate time frame and withdrawal rate, and minimizing error in the global mass balance of the model.

  5. Photoinduced surface voltage mapping study for large perovskite single crystals

    NASA Astrophysics Data System (ADS)

    Liu, Xiaojing; Liu, Yucheng; Gao, Fei; Yang, Zhou; Liu, Shengzhong Frank

    2016-05-01

    Using a series of illumination sources, including white light (tungsten-halogen lamp), 445-nm, 532-nm, 635-nm, and 730-nm lasers, the surface photovoltage (SPV) images were mapped for centimeter-sized CH3NH3PbX3 (X = Cl, Br, I) perovskite single crystals using Kelvin probe force microscopy. The significant SPV signals were observed to be wavelength-dependent. We attribute the appreciable SPV to the built-in electric field in the space charge region. This study shines light into the understanding of photoinduced charge generation and separation processes at nanoscale to help advance the development of perovskite solar cells, optoelectronics, laser, photodetector, and light-emitting diode (LED).

  6. Surface towed electromagnetic system for mapping of subsea Arctic permafrost

    NASA Astrophysics Data System (ADS)

    Sherman, Dallas; Kannberg, Peter; Constable, Steven

    2017-02-01

    Sea level has risen globally since the late Pleistocene, resulting in permafrost-bearing coastal zones in the Arctic being submerged and subjected to temperature induced degradation. Knowing the extent of permafrost and how it changes over time is important for climate change predictions and for planning engineering activities in the Arctic environment. We developed a controlled source electromagnetic (CSEM) method to obtain information on the depth, thickness, and lateral extent of marine permafrost. To operate in shallow water we used a surface towed electric dipole-dipole CSEM system suitable for deployment from small boats. This system was used to map permafrost on the Arctic shelf offshore Prudhoe Bay, Alaska. Our results show significant lateral variability in the presence of permafrost, with the thickest layers associated with a large river outflow where freshwater influx seems to have a preserving effect on relict subsea permafrost.

  7. Surface mapping of selected regions in the Orion Nebula

    NASA Technical Reports Server (NTRS)

    Perry, P. M.; Turnrose, B. E.; Harvel, C. A.; Thompson, R. W.; Mallama, A. D.

    1981-01-01

    Low dispersion, large aperture, ultraviolet spectra of selected regions in the Orion Nebula were obtained with the International Ultraviolet Explorer (IUE) scientific instrument. Spectra obtained at 35 contiguous locations defining a mosaic within the nebula were used to generate monochromatic images of high spatial resolution at the wavelengths of the ultraviolet emission lines. Image processing techniques were utilized to generate and analyze these ultraviolet surface maps. The imagery at the three wavelengths studied shows definite differences in the spatial distribution of emission from the CII CIII and OII ions. Ways of using the imagery to determine ionization structure and C/O abundance ratios throughout the regions observed are developed, in addition to means of analyzing the extensive continuum measurements in terms of dust scattering characteristics.

  8. Joint Assimilation of Piezometric Heads and Groundwater Temperatures with the Ensemble Kalman Filter for Managed River-Aquifer Systems

    NASA Astrophysics Data System (ADS)

    Kurtz, W.; Hendricks Franssen, H.; Kaiser, H.; Vereecken, H.

    2013-12-01

    Data assimilation techniques, like the ensemble Kalman filter (EnKF), are increasingly applied to groundwater systems to improve the (real-time) prediction of groundwater states and the estimation of uncertain hydraulic subsurface parameters. The most commonly assimilated data types for managed groundwater systems are groundwater levels and, less frequently, tracer test data. Especially for managed groundwater systems that are affected by river-aquifer exchange, measured groundwater temperature data can provide an additional source of information for the identification of hydraulic subsurface parameters. Additionally, an improved prediction of the temperature field itself is often desirable for groundwater management, e.g. in order to regulate the temperature of extracted drinking water. The scope of this study is to investigate the worth of a joint assimilation of hydraulic and thermal observation data on the state and parameter estimation with EnKF. Two different model setups were applied: (i) a simple synthetic model of a river-aquifer system where the parameters and simulation conditions were perfectly known (ii) a model of the Limmat aquifer in Zurich (Switzerland) where an exhaustive set of real-world observations of groundwater levels and temperatures was available for assimilation and verification. High-performance computing using a parallel implementation of EnKF made it possible to cope with the high computational burden that is associated with the stochastic simulation of heat transport processes that was applied in this study. Results for the synthetic case suggest that a joint assimilation of piezometric heads and groundwater temperatures together with updating of uncertain hydraulic conductivities and leakage coefficients gives the best estimation of states and hydraulic properties of the model. Focusing on the river streambed, we found that the assimilated piezometric head data mainly gave information on the magnitude of river-aquifer exchange fluxes

  9. Revised potentiometric-surface map, Yucca Mountain and vicinity, Nevada

    USGS Publications Warehouse

    Ervin, E.M.; Luckey, R.R.; Burkhardt, D.J.

    1993-01-01

    The revised potentiometric-surface map presented in this report updates earlier maps of the Yucca Mountain area using mainly 1988 average water levels. Because of refinements in the corrections to the water-level measurements, these water levels have increased accuracy and precision over older values. The small-gradient area to the southeast of Yucca Mountain is contoured with a 0.25-meter interval and ranges in water-level altitude from 728.5 to 731.0 meters. Other areas with different water levels, to the north and west of Yucca Mountain, are illustrated with shaded patterns. The potentiometric surface can be divided into three regions: 1) A small-gradient area to the southeast of Yucca Mountain, which may be explained by flow through high-transmissivity rocks or low ground-water flux through the area; 2) A moderate-gradient area, on the western side of Yucca Mountain, where the water-level altitude ranges from 775 to 780 meters, and appears to be impeded by the Solitario Canyon Fault and a splay of that fault; and 3) A large-gradient area, to the north-northeast of Yucca Mountain, where water level altitude ranges from 738 to 1,035 meters, possibly as a result of a semi-perched groundwater system. Water levels from wells at Yucca Mountain were examined for yearly trends (1986-89) using linear least-squares regression. Data from five wells exhibited trends which were statistically significant, but some of those may be a result of slow equilibration of the water level from drilling in less permeable rocks. Adjustments for temperature and density changes in the deep wells with long fluid columns were attempted, but some of the adjusted data did not fit the surrounding data and, thus, were not used.

  10. Deformable structure registration of bladder through surface mapping

    SciTech Connect

    Li Xiong; Viswanathan, Akila; Stewart, Alexandra J.; Haker, Steven; Tempany, Clare M.; Chin, Lee M.; Cormack, Robert A.

    2006-06-15

    Cumulative dose distributions in fractionated radiation therapy depict the dose to normal tissues and therefore may permit an estimation of the risk of normal tissue complications. However, calculation of these distributions is highly challenging because of interfractional changes in the geometry of patient anatomy. This work presents an algorithm for deformable structure registration of the bladder and the verification of the accuracy of the algorithm using phantom and patient data. In this algorithm, the registration process involves conformal mapping of genus zero surfaces using finite element analysis, and guided by three control landmarks. The registration produces a correspondence between fractions of the triangular meshes used to describe the bladder surface. For validation of the algorithm, two types of balloons were inflated gradually to three times their original size, and several computerized tomography (CT) scans were taken during the process. The registration algorithm yielded a local accuracy of 4 mm along the balloon surface. The algorithm was then applied to CT data of patients receiving fractionated high-dose-rate brachytherapy to the vaginal cuff, with the vaginal cylinder in situ. The patients' bladder filling status was intentionally different for each fraction. The three required control landmark points were identified for the bladder based on anatomy. Out of an Institutional Review Board (IRB) approved study of 20 patients, 3 had radiographically identifiable points near the bladder surface that were used for verification of the accuracy of the registration. The verification point as seen in each fraction was compared with its predicted location based on affine as well as deformable registration. Despite the variation in bladder shape and volume, the deformable registration was accurate to 5 mm, consistently outperforming the affine registration. We conclude that the structure registration algorithm presented works with reasonable accuracy and

  11. Deformable structure registration of bladder through surface mapping.

    PubMed

    Xiong, Li; Viswanathan, Akila; Stewart, Alexandra J; Haker, Steven; Tempany, Clare M; Chin, Lee M; Cormack, Robert A

    2006-06-01

    Cumulative dose distributions in fractionated radiation therapy depict the dose to normal tissues and therefore may permit an estimation of the risk of normal tissue complications. However, calculation of these distributions is highly challenging because of interfractional changes in the geometry of patient anatomy. This work presents an algorithm for deformable structure registration of the bladder and the verification of the accuracy of the algorithm using phantom and patient data. In this algorithm, the registration process involves conformal mapping of genus zero surfaces using finite element analysis, and guided by three control landmarks. The registration produces a correspondence between fractions of the triangular meshes used to describe the bladder surface. For validation of the algorithm, two types of balloons were inflated gradually to three times their original size, and several computerized tomography (CT) scans were taken during the process. The registration algorithm yielded a local accuracy of 4 mm along the balloon surface. The algorithm was then applied to CT data of patients receiving fractionated high-dose-rate brachytherapy to the vaginal cuff, with the vaginal cylinder in situ. The patients' bladder filling status was intentionally different for each fraction. The three required control landmark points were identified for the bladder based on anatomy. Out of an Institutional Review Board (IRB) approved study of 20 patients, 3 had radiographically identifiable points near the bladder surface that were used for verification of the accuracy of the registration. The verification point as seen in each fraction was compared with its predicted location based on affine as well as deformable registration. Despite the variation in bladder shape and volume, the deformable registration was accurate to 5 mm, consistently outperforming the affine registration. We conclude that the structure registration algorithm presented works with reasonable accuracy and

  12. A POD Mapping Approach to Emulate Land Surface Models

    NASA Astrophysics Data System (ADS)

    Pau, G. S. H.; Bisht, G.; Liu, Y.; Riley, W. J.; Shen, C.

    2014-12-01

    Existing land surface models (LSMs) describe physical and biological processes that occur over a wide range of spatial and temporal scales. Since simulating LSMs at a spatial scale to explicitly resolve the finest resolution processes is computationally expensive, upscaling techniques are used in LSMs to capture effect of subgrid heterogeneity. However, routinely employed linear upscaling techniques that allow LSMs to be simulated at coarse spatial resolution can result in large prediction error. To efficiently predict fine-resolution solutions to LSMs, we studied the application of a reduce order model (ROM) technique known as the "Proper Orthogonal Decomposition mapping method" that reconstructs temporally-resolved fine-resolution solutions based on coarse-resolution solutions for two case studies. In the first case study, we applied POD approach on surface-subsurface isothermal simulations for four study sites (104 [m2]) in a polygonal tundra landscape near Barrow, Alaska. The results indicate that the ROM produced a significant computational speedup (>103) with very small relative approximation error (<0.1%) for two validation years not used in training the ROM. In the second case study, we illustrate the applicability of our ROM approach at watershed scale (1837 km2) model that is substantially more heterogeneous and demonstrate a hierarchical approach to emulating models at spatial scales consistent with mechanistic physical process representation.

  13. Mapping currents at the corroding surface/solution interface

    SciTech Connect

    Isaacs, H.S.; Ryan, M.P.; Oblonsky, L.J.

    1997-04-01

    Corrosion is electrochemical in nature. The kinetics of the processes taking place are controlled by the potential of the metal in its environment. The potentials of corroding metals can be measured against a reference electrode in virtually all cases. However, the currents and corrosion rates are generally difficult to determine directly. The flow of current in solution depends on the corrosion processes taking place. When the corrosion is uniform, then conceptually there need not be currents flowing in solution as the anodic and cathodic reactions take place at the same sites on the surface. This may be the case for both very high or low corrosion rates. In acidic solution, where rapid corrosion takes place, models which envision migration of separate anodic and cathodic sites have been proposed. With passive surfaces, the anodic and cathodic sites are considered to be separated by the thickness of the passive layer which acts as a mixed electrolyte, conducting both ions and electrons. This is similar to the processes taking place during high temperature oxidation. Direct measurement of these currents have not been made. It is generally necessary to produce changes in the system, by applying external voltages, to ascertain the behavior of the currents through measurement of changes in the net current. This can only be done on small areas of metal. Corrosion rates can then be determined by extrapolation back to the open circuit potential. This paper describes studies in current density mapping for the understanding of corrosion.

  14. Elemental mapping of planetary surfaces using gamma-ray spectroscopy

    SciTech Connect

    Reedy, R.C.

    1990-01-01

    The gamma rays escaping from a planet can be used to map the concentrations of various elements in its surface. In a planet, the high-energy particles in the galactic cosmic rays induce a cascade of particles that includes many neutrons. The {gamma} rays are made by the nuclear excitations induced by these cosmic-ray particles and their secondaries (especially capture or inelastic-scattering reactions induced by neutrons) and decay of the naturally-occurring radioelements. After a short history of planetary {gamma}-ray spectroscopy and its applications, the {gamma}-ray spectrometer planned for the Mars Observer mission is presented. The results of laboratory experiments that simulate the cosmic-ray bombardments of planetary surfaces or measure cross sections for the production of {gamma} rays and the status of the theoretical calculations for the processes that make and transport neutrons and {gamma} rays will be reviewed. The emphasis here is on studies of Mars and on new ideas, concepts, and problems that have arisen over the last decade, such as Doppler broadening and peaks from neutron scattering with germanium nuclei in a high-resolution {gamma}-ray spectrometer. 31 refs., 1 fig., 1 tab.

  15. ENSO signature in the SMOS sea surface salinity maps

    NASA Astrophysics Data System (ADS)

    Ballabrera, J.; Umbert, M.; Hoareau, N.; Turiel, A.; Font, J.

    2012-12-01

    Until recently, the role of salinity observations in the operational simulation and prediction of ENSO was neglected because of the historical lack of observations and because leading intermediate coupled models had significant predictive skill without directly accounting for salinity effects. In Ballabrera-Poy et al., (2002), the potential role of sea surface salinity (SSS) observations on the statistical predictions of ENSO was investigated. It was shown that, although SSS observations would play little role in statistical nowcasts of ENSO, they would provide a significant role in the 6-12 month predictions. The European Space Agency (ESA) Soil Moisture and Ocean Salinity (SMOS) Earth Explorer opportunity mission was launched on November 2, 2009, becoming the first satellite mission addressing the challenge of measuring SSS from space with the help of MIRAS (Microwave Imaging Radiometer with Aperture Synthesis), a novel two-dimensional interferometer operating at L-band (1.4 GHz). Although the L-band frequency is the optimal for ocean salinity measurements, the retrieval of SSS information requires special care because of the low sensitivity of the brightness temperature to SSS: from 0.2-0.8 K per salinity unit. Maps of 10-day averages of SSS in 1x1 degree boxes are distributed by the SMOS Barcelona Expert Centre on Radiometric Calibration and Ocean Salinity (SMOS-BEC, http://www.smos-bec.icm.csic.es). These maps are derived from the SMOS reprocessing campaign released to the SMOS user community in March 2011, and span the period from January 2010 through December 2011. The current accuracy of these SSS maps ranges from 0.2-0.4, depending on the ocean region being considered (Umbert et al., 2012). During the period of the reprocessing campaign, the equatorial Pacific has been in a quasi-continuous La Niña state. During the cold phases of ENSO, positive anomalies of SSS are expected with a largest anomalous values in the western warm-fresh pool. The anomalies

  16. Direct Cortical Mapping via Solving Partial Differential Equations on Implicit Surfaces

    PubMed Central

    Shi, Yonggang; Thompson, Paul M.; Dinov, Ivo; Osher, Stanley; Toga, Arthur W.

    2007-01-01

    In this paper, we propose a novel approach for cortical mapping that computes a direct map between two cortical surfaces while satisfying constraints on sulcal landmark curves. By computing the map directly, we can avoid conventional intermediate parameterizations and help simplify the cortical mapping process. The direct map in our method is formulated as the minimizer of a flexible variational energy under landmark constraints. The energy can include both a harmonic term to ensure smoothness of the map and general data terms for the matching of geometric features. Starting from a properly designed initial map, we compute the map iteratively by solving a partial differential equation (PDE) defined on the source cortical surface. For numerical implementation, a set of adaptive numerical schemes are developed to extend the technique of solving PDEs on implicit surfaces such that landmark constraints are enforced. In our experiments, we show the flexibility of the direct mapping approach by computing smooth maps following landmark constraints from two different energies. We also quantitatively compare the metric preserving property of the direct mapping method with a parametric mapping method on a group of 30 subjects. Finally, we demonstrate the direct mapping method in the brain mapping applications of atlas construction and variability analysis. PMID:17379568

  17. Direct cortical mapping via solving partial differential equations on implicit surfaces.

    PubMed

    Shi, Yonggang; Thompson, Paul M; Dinov, Ivo; Osher, Stanley; Toga, Arthur W

    2007-06-01

    In this paper, we propose a novel approach for cortical mapping that computes a direct map between two cortical surfaces while satisfying constraints on sulcal landmark curves. By computing the map directly, we can avoid conventional intermediate parameterizations and help simplify the cortical mapping process. The direct map in our method is formulated as the minimizer of a flexible variational energy under landmark constraints. The energy can include both a harmonic term to ensure smoothness of the map and general data terms for the matching of geometric features. Starting from a properly designed initial map, we compute the map iteratively by solving a partial differential equation (PDE) defined on the source cortical surface. For numerical implementation, a set of adaptive numerical schemes are developed to extend the technique of solving PDEs on implicit surfaces such that landmark constraints are enforced. In our experiments, we show the flexibility of the direct mapping approach by computing smooth maps following landmark constraints from two different energies. We also quantitatively compare the metric preserving property of the direct mapping method with a parametric mapping method on a group of 30 subjects. Finally, we demonstrate the direct mapping method in the brain mapping applications of atlas construction and variability analysis.

  18. Heat capacity mapping mission (HCMM) thermal surface water mapping and its correlation to LANDSAT

    SciTech Connect

    Colvocoresses, A.P.

    1980-03-01

    Graphics are presented which show HCMM mapped water-surface temperature in Lake Anna, a 13,000 dendrically-shaped lake which provides cooling for a nuclear power plant in Virginia. The HCMM digital data, produced by NASA were processed by NOAA/NESS into image and line-printer form. A LANDSAT image of the lake illustrates the relationship between MSS band 7 data and the HCMM data as processed by the NASA image processing facility which transforms the data to the same distortion-free hotline oblique Mercator projection. Spatial correlation of the two images is relatively simple by either digital or analog means and the HCMM image has a potential accuracy approaching the 80 m of the original LANDSAT data. While it is difficult to get readings that are not diluted by radiation from cooler adjacent land areas in narrow portions of the lake, digital data indicated by the line-printer display five different temperatures for open-water areas. Where the water surface response was not diluted by land areas, the temperature difference recorded by HCMM corresponds to in situ readings with rsme on the order of 1 C.

  19. Landmark constrained genus-one surface Teichmüller map applied to surface registration in medical imaging.

    PubMed

    Lam, Ka Chun; Gu, Xianfeng; Lui, Lok Ming

    2015-10-01

    We address the registration problem of genus-one surfaces (such as vertebrae bones) with prescribed landmark constraints. The high-genus topology of the surfaces makes it challenging to obtain a unique and bijective surface mapping that matches landmarks consistently. This work proposes to tackle this registration problem using a special class of quasi-conformal maps called Teichmüller maps (T-Maps). A landmark constrained T-Map is the unique mapping between genus-1 surfaces that minimizes the maximal conformality distortion while matching the prescribed feature landmarks. Existence and uniqueness of the landmark constrained T-Map are theoretically guaranteed. This work presents an iterative algorithm to compute the T-Map. The main idea is to represent the set of diffeomorphism using the Beltrami coefficients (BC). The BC is iteratively adjusted to an optimal one, which corresponds to our desired T-Map that matches the prescribed landmarks and satisfies the periodic boundary condition on the universal covering space. Numerical experiments demonstrate the effectiveness of our proposed algorithm. The method has also been applied to register vertebrae bones with prescribed landmark points and curves, which gives accurate surface registrations.

  20. Cancer Risk Map for the Surface of Mars

    NASA Technical Reports Server (NTRS)

    Kim, Myung-Hee Y.; Cucinotta, Francis A.

    2011-01-01

    We discuss calculations of the median and 95th percentile cancer risks on the surface of Mars for different solar conditions. The NASA Space Radiation Cancer Risk 2010 model is used to estimate gender and age specific cancer incidence and mortality risks for astronauts exploring Mars. Organ specific fluence spectra and doses for large solar particle events (SPE) and galactic cosmic rays (GCR) at various levels of solar activity are simulated using the HZETRN/QMSFRG computer code, and the 2010 version of the Badhwar and O Neill GCR model. The NASA JSC propensity model of SPE fluence and occurrence is used to consider upper bounds on SPE fluence for increasing mission lengths. In the transport of particles through the Mars atmosphere, a vertical distribution of Mars atmospheric thickness is calculated from the temperature and pressure data of Mars Global Surveyor, and the directional cosine distribution is implemented to describe the spherically distributed atmospheric distance along the slant path at each elevation on Mars. The resultant directional shielding by Mars atmosphere at each elevation is coupled with vehicle and body shielding for organ dose estimates. Astronaut cancer risks are mapped on the global topography of Mars, which was measured by the Mars Orbiter Laser Altimeter. Variation of cancer risk on the surface of Mars is due to a 16-km elevation range, and the large difference is obtained between the Tharsis Montes (Ascraeus, Pavonis, and Arsia) and the Hellas impact basin. Cancer incidence risks are found to be about 2-fold higher than mortality risks with a disproportionate increase in skin and thyroid cancers for all astronauts and breast cancer risk for female astronauts. The number of safe days on Mars to be below radiation limits at the 95th percent confidence level is reported for several Mission design scenarios.

  1. Presentation of a surface runoff susceptibility mapping method and its application to the Lezarde catchment

    NASA Astrophysics Data System (ADS)

    Lagadec, Lilly-Rose; Patrice, Pierre; Chazelle, Blandine; Braud, Isabelle; Dehotin, Judicaël; Hauchard, Emmanuel; Breil, Pascal

    2016-04-01

    Intense surface runoff is a hydrological process at the origin of intense phenomena such as erosion, flash floods, and mudslides and can generate major damage. In this paper, we present a mapping method to represent the susceptibility of surface runoff occurrence. The method, called IRIP (Indicator of Intense Pluvial Runoff, French acronym) produces 3 maps representing 3 steps of the surface runoff phenomena: generation, transfer and accumulation. The maps area created by combining surface runoff factors extracted from topography, soil properties and land use. Each map has a six level scale of susceptibility, from 0 (low susceptibility) to 5 (strong susceptibility). The method is applied in the Lézarde catchment (210 km², northern France) known to be prone to intense surface runoff. The relevance of the mapping method results is evaluated by comparing the susceptibility maps to data related to surface runoff: risk regulatory zonings of surface runoff and erosion, and surface runoff impacts on the transportation network (roads and railways). The relationship between the comparison data sets and the susceptibility maps can be indirect, so, a method of comparison is proposed. Similarity indexes are computed for the regulatory zonings and detection rates are computed for the damaged transportation network sections. The comparison shows good correlation between the surface runoff zoning map and the susceptibility map of accumulation, and between the soil erosion zoning and the susceptibility map of transfer. High detection rates are obtained when comparing the damaged network sections and the susceptibility maps of transfer and accumulation. The paper also opens interesting prospects to improve the the mapping method and method of evaluation.

  2. Lunar Flashlight: Mapping Lunar Surface Volatiles Using a Cubesat

    NASA Technical Reports Server (NTRS)

    Cohen, B. A.; Hayne, P. O.; Banazadeh, P.; Baker, J. D.; Staehle, R. L.; Paine, C..; Paige, D. A.

    2014-01-01

    Water ice and other volatiles may be located in the Moon's polar regions, with sufficient quantities for in situ extraction and utilization by future human and robotic missions. Evidence from orbiting spacecraft and the LCROSS impactor suggests the presence of surface and/or nearsurface volatiles, including water ice. These deposits are of interest to human exploration to understand their potential for use by astronauts. Understanding the composition, quantity, distribution, and form of water/H species and other volatiles associated with lunar cold traps is identified as a NASA Strategic Knowledge Gap (SKG) for Human Exploration. These polar volatile deposits could also reveal important information about the delivery of water to the Earth- Moon system, so are of scientific interest. The scientific exploration of the lunar polar regions was one of the key recommendations of the Planetary Science Decadal Survey. In order to address NASA's SKGs, the Advanced Exploration Systems (AES) program selected three lowcost 6-U CubeSat missions for launch as secondary payloads on the first test flight (EM1) of the Space Launch System (SLS) scheduled for 2017. The Lunar Flashlight mission was selected as one of these missions, specifically to address the SKG associated with lunar volatiles. Development of the Lunar Flashlight CubeSat concept leverages JPL's Interplanetary Nano- Spacecraft Pathfinder In Relevant Environment (INSPIRE) mission, MSFC's intimate knowledge of the Space Launch System and EM-1 mission, small business development of solar sail and electric propulsion hardware, and JPL experience with specialized miniature sensors. The goal of Lunar Flashlight is to determine the presence or absence of exposed water ice and its physical state, and map its concentration at the kilometer scale within the permanently shadowed regions of the lunar south pole. After being ejected in cislunar space by SLS, Lunar Flashlight deploys its solar panels and solar sail and maneuvers

  3. Electrocardiographic markers of ischemia during mental stress testing in postinfarction patients. Role of body surface mapping

    SciTech Connect

    Bosimini, E.; Galli, M.; Guagliumi, G.; Giubbini, R.; Tavazzi, L. )

    1991-04-01

    In patients with coronary artery disease, radionuclide investigations have documented a high incidence of mental stress-induced myocardial ischemia in the absence of significant electrocardiographic changes and/or angina. To investigate the causes of the low electrocardiographic sensitivity, we recorded body surface maps during mental arithmetic in 22 normal volunteers and 37 postinfarction patients with residual exercise ischemia. Myocardial perfusion was studied with thallium-201 or technetium-99 (SESTAMIBI) planar scans. In 14 patients, body surface maps were also recorded during atrial pacing at the heart rate values achieved during mental stress. While taking the body surface maps, the area from J point to 80 msec after this point (ST-80) was analyzed by integral maps, difference maps, and departure maps. The body surface mapping criteria for ischemia were a new negative area on the integral maps, a negative potential of more than 2 SD from mean normal values on the difference maps, and a negative departure index of more than 2. Scintigraphy showed asymptomatic myocardial hypoperfusion in 33 patients. Eight patients had significant ST segment depression. The ST-80 integral and difference maps identified 17 ischemic patients. Twenty-four patients presented abnormal departure maps. One patient presented ST depression and abnormal body surface maps without reversible tracer defect. In 14 of 14 patients, atrial pacing did not reproduce the body surface map abnormalities. The analyses of the other electrocardiographic variables showed that in patients with mental stress-induced perfusion defects, only changes of T apex-T offset (aT-eT) interval in Frank leads and changes of maximum negative potential value of aT-eT integral maps significantly differed from those of normal subjects.

  4. Multi-resolution mapping using surface, descent and orbit images

    NASA Technical Reports Server (NTRS)

    Olson, C.; Matthies, L.; Xiong, Y.; Li, R.; Ma, F.

    2001-01-01

    Our objective is to produce high-accuracy maps of the terrain elevation at landing sites on planetary bodies through the use of all available image data. These technologies are important for performing rover navigation in future space missions and the maps provide a tool for coordinating rovers in a robotic colony.

  5. Remote compositional mapping of lunar titanium and surface maturity

    NASA Technical Reports Server (NTRS)

    Johnson, J. R.; Larson, S. M.; Singer, Robert B.

    1991-01-01

    Lunar ilmenite (FeTiO3) is a potential resource capable of providing oxygen for life support and spacecraft propellant for future lunar bases. Estimates of TiO2 content in mature mare soils can be made using an empirical relation between the 400/500 nm reflectance ratio and TiO2 wt percent. A TiO2 abundance map was constructed for the entire near-side lunar maria accurate to + or - 2 wt percent TiO2 using CCD images obtained at the Tumamoc Hill 0.5 m telescope in Tucson, employing bandpass filters centered at 400 and 560 nm. Highest TiO2 regions in the maria are located in western Mare Tranquillitatis. Greater contrast differences between regions on the lunar surface can be obtained using 400/730 nm ratio images. The relation might well be refined to accommodate this possibly more sensitive indicator of TiO2 content. Another potential lunar resource is solar wind-implanted He-3 which may be used as a fuel for fusion reactors. Relative soil maturity, as determined by agglutinate content, can be estimated from 950/560 nm ration images. Immature soils appear darker in this ratio since such soils contain abundant pyroxene grains which cause strong absorption centered near 950 nm due Fe(2+) crystal field transitions. A positive correlation exists between the amount of He-3 and TiO2 content in lunar soils, suggesting that regions high in TiO2 should also be high in He-3. Reflectance spectrophotometry in the region 320 to 870 nm was also obtained for several regions. Below about 340 nm, these spectra show variations in relative reflectance that are caused by as yet unassigned near-UV absorptions due to compositional differences.

  6. Method for Pre-Conditioning a Measured Surface Height Map for Model Validation

    NASA Technical Reports Server (NTRS)

    Sidick, Erkin

    2012-01-01

    This software allows one to up-sample or down-sample a measured surface map for model validation, not only without introducing any re-sampling errors, but also eliminating the existing measurement noise and measurement errors. Because the re-sampling of a surface map is accomplished based on the analytical expressions of Zernike-polynomials and a power spectral density model, such re-sampling does not introduce any aliasing and interpolation errors as is done by the conventional interpolation and FFT-based (fast-Fourier-transform-based) spatial-filtering method. Also, this new method automatically eliminates the measurement noise and other measurement errors such as artificial discontinuity. The developmental cycle of an optical system, such as a space telescope, includes, but is not limited to, the following two steps: (1) deriving requirements or specs on the optical quality of individual optics before they are fabricated through optical modeling and simulations, and (2) validating the optical model using the measured surface height maps after all optics are fabricated. There are a number of computational issues related to model validation, one of which is the "pre-conditioning" or pre-processing of the measured surface maps before using them in a model validation software tool. This software addresses the following issues: (1) up- or down-sampling a measured surface map to match it with the gridded data format of a model validation tool, and (2) eliminating the surface measurement noise or measurement errors such that the resulted surface height map is continuous or smoothly-varying. So far, the preferred method used for re-sampling a surface map is two-dimensional interpolation. The main problem of this method is that the same pixel can take different values when the method of interpolation is changed among the different methods such as the "nearest," "linear," "cubic," and "spline" fitting in Matlab. The conventional, FFT-based spatial filtering method used to

  7. Preliminary Correlation Map of Geomorphic Surfaces in North-Central Frenchman Flat, Nevada Test Site

    SciTech Connect

    Bechtel Nevada

    2005-08-01

    This correlation map (scale = 1:12,000) presents the results of a mapping initiative that was part of the comprehensive site characterization required to operate the Area 5 Radioactive Waste Management Site, a low-level radioactive waste disposal facility located in northern Frenchman Flat at the Nevada Test Site. Eight primary map units are recognized for Quaternary surfaces: remnants of six alluvial fan or terrace surfaces, one unit that includes colluvial aprons associated with hill slopes, and one unit for anthropogenically disturbed surfaces. This surficial geology map provides fundamental data on natural processes for reconstruction of the Quaternary history of northern Frenchman Flat, which in turn will aid in the understanding of the natural processes that act to develop the landscape, and the time-frames involved in landscape development. The mapping was conducted using color and color-infrared aerial photographs and field verification of map unit composition and boundaries. Criteria for defining the map unit composition of geomorphic surface units are based on relative geomorphic position, landform morphology, and degree of preservation of surface morphology. The bedrock units identified on this map were derived from previous published mapping efforts and are included for completeness.

  8. Surface height map estimation from a single image using convolutional neural networks

    NASA Astrophysics Data System (ADS)

    Zhou, Xiaowei; Zhong, Guoqiang; Qi, Lin; Dong, Junyu; Pham, Tuan D.; Mao, Jianzhou

    2017-02-01

    Surface height map estimation is an important task in high-resolution 3D reconstruction. This task differs from general scene depth estimation in the fact that surface height maps contain more high frequency information or fine details. Existing methods based on radar or other equipments can be used for large-scale scene depth recovery, but might fail in small-scale surface height map estimation. Although some methods are available for surface height reconstruction based on multiple images, e.g. photometric stereo, height map estimation directly from a single image is still a challenging issue. In this paper, we present a novel method based on convolutional neural networks (CNNs) for estimating the height map from a single image, without any equipments or extra prior knowledge of the image contents. Experimental results based on procedural and real texture datasets show the proposed algorithm is effective and reliable.

  9. Mapping Near-Surface Salinization Using Long-wavelength AIRSAR

    NASA Technical Reports Server (NTRS)

    Paine, Jeffery G.

    2003-01-01

    In May 1999, NASA's Jet Propulsion Laboratory acquired airborne synthetic aperture radar (AIRSAR) data over the Hatchel and Montague Test Sites in Texas. We analyzed P- and L-band polarimetric radar data from these AIRSAR missions to assess whether AIRSAR could be used as a rapid and remote platform for screening large areas at risk for near-surface soil and water salinization. Ongoing geological, geophysical, and hydrological studies at the Hatchel Test Site in Runnels County and the Montague Test Site in Montague County have demonstrated the utility of high-resolution airborne electromagnetic (EM) induction in mapping electrical conductivity changes that accompany shallow natural and oil-field related salinization at these sites in the Colorado and Red River basins. We compared AIRSAR and airborne EM data quantitatively by (1) selecting representative flight lines from airborne EM surveys of the Hatchel and Montague sites, (2) extracting measurement locations and apparent conductivities at the highest available EM frequency, (3) identifying and extracting all P- and L-band backscatter intensities for all locations within 5 m of an airborne EM measurement, and (4) examining the spatial and magnitude relationships between apparent conductivity and all radar polarization and polarization-ratio combinations. For both test sites, backscatter intensity in all individual P- and L-band polarizations was slightly negatively correlated with apparent conductivity. In most modes this was manifested as a decrease in the range and magnitude of backscatter intensity as apparent conductivity increased. Select single-band and cross-band polarization ratios exhibited somewhat higher correlation with apparent conductivity by partly diminishing the dominance of the vegetation contribution to V backscatter intensity. The highest correlation with conductivity was obtained using the L-band vertical- to cross-polarization ratio, the P-band vertical- to L-band cross-polarization ratio

  10. The role of peat double porosity on groundwater-surface water interaction in a drained fen

    NASA Astrophysics Data System (ADS)

    Rossi, P. M.; Ala-aho, P.; Ronkanen, A.-K.

    2012-04-01

    Groundwater discharge from an esker aquifer to a fen was studied to understand relevant hydrological processes for surface-groundwater interaction in an esker-peatland hillslope. Piezometric levels of the peat layer and esker sand layer were continuously monitored and compared to climate data. Groundwater exfiltration points were spatially mapped and related to peat depth. The study showed a clear interaction between fen surface water and sand esker groundwater although the hydraulic conductivity of peat was low and the peat depth thick. In the artesian aquifer beneath the fen, the piezometric head showed a clear response to precipitation and evapotranspiration. Wetting of the peat is rapidly seen as pressure increase in the confined aquifer. This provides new information on hydraulics of wetlands found in aquifer discharge areas. Groundwater exfiltrated through thick peat layers in vertical preferential point discharges demonstrating how double porosity provides flow through the peat layer with low hydraulic conductivity in the peat matrix. The "pipe flow" channels were found in the deep peat area in the transition zones from deep peat to shallow peat. Diffuse seepage through the ditch bottom was found where ditches cut into the sand layer. Increased discharge through the ditch bed reduced the flow resistance at the aquifer boundary which can lower the groundwater level in the esker. The results show new processes in the groundwater discharge zone that are useful for groundwater modeling and policy development for future groundwater protection.

  11. Groundwater-surface water interaction between an esker aquifer and a drained fen

    NASA Astrophysics Data System (ADS)

    Rossi, Pekka M.; Ala-aho, Pertti; Ronkanen, Anna-Kaisa; Kløve, Bjørn

    2012-04-01

    SummaryGroundwater discharge from an esker aquifer to a fen was studied to understand relevant hydrological processes for groundwater-surface water interaction in an esker-peatland hillslope. Piezometric levels of the peat layer and esker sand layer were continuously monitored and compared to climate data. Groundwater exfiltration points were spatially mapped and related to peat depth. The study showed a clear interaction between fen surface water and sand esker groundwater although the hydraulic conductivity of peat was low and the peat depth thick. In the artesian aquifer beneath the fen, the piezometric head showed a clear response to precipitation and evapotranspiration. Wetting of the peat is rapidly seen as pressure increase in the confined aquifer. This provides new information on hydraulics of wetlands found in aquifer discharge areas. Groundwater exfiltrated through thick peat layers in vertical preferential point discharges demonstrating how double porosity provides flow through the peat layer with low hydraulic conductivity in the peat matrix. The "pipe flow" channels were found in the deep peat area in the transition zones from deep peat to shallow peat. Diffuse seepage through the ditch bottom was found where ditches cut into the sand layer. Increased discharge through the ditch bed reduced the flow resistance at the aquifer boundary which can lower the groundwater level in the esker. The results show new processes in the groundwater discharge zone that are useful for groundwater modelling and policy development for future groundwater protection.

  12. Surface mapping of three components of the lunar magnetic anomaly field: Preliminary results

    NASA Astrophysics Data System (ADS)

    Tsunakawa, H.; Takahashi, F.; Shimizu, H.; Shibuya, H.; Matsushima, M.

    2010-12-01

    Mapping of the lunar magnetic anomaly gives a crucial constraint on the crustal magnetization structure of the Moon. High spatial resolution of the magnetic anomaly map requires low altitude mapping. We have developed a new method for mapping three components of the lunar magnetic anomaly field on the lunar surface using magnetic field observations by a satellite magnetometer. This surface mapping method was applied to the datasets of several lunar magnetic anomaly regions observed by Lunar Prospector and Kaguya. We will report their preliminary results. The radial component of the crustal magnetic field (Br) on the surface can be obtained from the satellite observations at various altitudes through the inversion of a boundary value problem (Tsunakawa et al., in press). In our method, surface Br values are mapped at almost equal interval points, called generalized spiral points. Two horizontal components are calculated at each point from Br values at the adjacent points. Thus we can map the surface values of three components and total intensity of the lunar magnetic anomaly field (Tsunakawa et al., in prep.). We have applied the method to several strong anomaly regions (e.g. Reiner Gamma) observed by Lunar Prospector and Kaguya. Since the observation altitudes are mostly 15-45 km, spatial resolutions are estimated to be 0.5-1 degree. Preliminary results show strong magnetic anomaly fields with intensity peaks of more than 500 nT on the lunar surface.

  13. Geomorphic Surface Maps of Northern Frenchman Flat, Nevada Test Site, Southern Nevada

    SciTech Connect

    Bechtel Nevada

    2005-08-01

    Large-scale (1:6000) surficial geology maps of northern Frenchman Flat were developed in 1995 as part of comprehensive site characterization required to operate a low-level radioactive waste disposal facility in that area. Seven surficial geology maps provide fundamental data on natural processes and are the platform needed to reconstruct the Quaternary history of northern Frenchman Flat. Reconstruction of the Quaternary history provides an understanding of the natural processes that act to develop the landscape, and the time-frames involved in landscape development. The mapping was conducted using color and color-infrared aerial photographs and field verification of map unit composition and boundaries. Criteria for defining the map unit composition of geomorphic surface units are based on relative geomorphic position, landform morphology, and degree of preservation of surface morphology. Seven geomorphic surfaces (Units 1 through 7) are recognized, spanning from the early Quaternary to present time.

  14. Mapping surface fluxes and moisture conditions from field to global scales using ALEXI/DisALEXI

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land-surface temperature (LST) maps derived from thermal infrared (TIR) satellite data convey valuable information for detecting moisture stress conditions and for constraining diagnostic surface flux estimates based on remote sensing. Soil surface and vegetation canopy temperatures rise as availab...

  15. Functional and structural mapping of human cerebral cortex: solutions are in the surfaces

    NASA Technical Reports Server (NTRS)

    Van Essen, D. C.; Drury, H. A.; Joshi, S.; Miller, M. I.

    1998-01-01

    The human cerebral cortex is notorious for the depth and irregularity of its convolutions and for its variability from one individual to the next. These complexities of cortical geography have been a chronic impediment to studies of functional specialization in the cortex. In this report, we discuss ways to compensate for the convolutions by using a combination of strategies whose common denominator involves explicit reconstructions of the cortical surface. Surface-based visualization involves reconstructing cortical surfaces and displaying them, along with associated experimental data, in various complementary formats (including three-dimensional native configurations, two-dimensional slices, extensively smoothed surfaces, ellipsoidal representations, and cortical flat maps). Generating these representations for the cortex of the Visible Man leads to a surface-based atlas that has important advantages over conventional stereotaxic atlases as a substrate for displaying and analyzing large amounts of experimental data. We illustrate this by showing the relationship between functionally specialized regions and topographically organized areas in human visual cortex. Surface-based warping allows data to be mapped from individual hemispheres to a surface-based atlas while respecting surface topology, improving registration of identifiable landmarks, and minimizing unwanted distortions. Surface-based warping also can aid in comparisons between species, which we illustrate by warping a macaque flat map to match the shape of a human flat map. Collectively, these approaches will allow more refined analyses of commonalities as well as individual differences in the functional organization of primate cerebral cortex.

  16. Optical and electrical mappings of surface plasmon cavity modes

    NASA Astrophysics Data System (ADS)

    Ye, Fan; Merlo, Juan M.; Burns, Michael J.; Naughton, Michael J.

    2014-04-01

    Plasmonics is a rapidly expanding field, founded in physics but now with a growing number of applications in biology (biosensing), nanophotonics, photovoltaics, optical engineering and advanced information technology. Appearing as charge density oscillations along a metal surface, excited by electromagnetic radiation (e.g., light), plasmons can propagate as surface plasmon polaritons, or can be confined as standing waves along an appropriately-prepared surface. Here, we review the latter manifestation, both their origins and the manners in which they are detected, the latter dominated by near field scanning optical microscopy (NSOM/SNOM). We include discussion of the "plasmonic halo" effect recently observed by the authors, wherein cavity-confined plasmons are able to modulate optical transmission through step-gap nanostructures, yielding a novel form of color (wavelength) selection.

  17. Thermal mapping of the lunar surface. [using infrared radiometry

    NASA Technical Reports Server (NTRS)

    Raine, W. L.

    1973-01-01

    A program of lunar infrared radiometry which uses large area scanning is described, and procedures for atmospheric attenuation correction and data reduction to temperature by relative radiometry are outlined. Flow charts of the computer data reduction program are shown which contain the astrometric analysis from ephemeral data. The scan data, taken on 10 evenings in 1971 and 1972 in the 10 to 12 micron window, are presented as isothermal contour maps of the lunar disc. More than 160 areas of anomalous thermal emission were found in the lunar darkside data. Eclipse cooling curves, measured in the same wavelength band for 7 lunar regions during the eclipse of February 10, 1971, are also presented. Errors of the scan and eclipse data were calculated from accuracy estimates of the parameters.

  18. Mapping land-surface fluxes of carbon, water and energy from field to regional scales

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A framework for routine mapping of land-surface fluxes of carbon, water, and energy at the field to regional scales has been established for drought monitoring, water resource management, yield forecasting and crop-growth monitoring. The framework uses the ALEXI/DisALEXI suite of land-surface model...

  19. Techniques for Down-Sampling a Measured Surface Height Map for Model Validation

    NASA Technical Reports Server (NTRS)

    Sidick, Erkin

    2012-01-01

    This software allows one to down-sample a measured surface map for model validation, not only without introducing any re-sampling errors, but also eliminating the existing measurement noise and measurement errors. The software tool of the current two new techniques can be used in all optical model validation processes involving large space optical surfaces

  20. Objectively mapping HF radar-derived surface current data using measured and idealized data covariance matrices

    NASA Astrophysics Data System (ADS)

    Kim, Sung Yong; Terrill, Eric; Cornuelle, Bruce

    2007-06-01

    Surface currents measured by high-frequency radars are objectively mapped using covariance matrices computed from hourly surface current vectors spanning two years. Since retrievals of surface radial velocities are inherently gappy in space and time, the irregular density of surface current data leads to negative eigenvalues in the sample covariance matrix. The number and the magnitude of the negative eigenvalues depend on the degree of data continuity used in the matrix computation. In a region of 90% data coverage, the negative eigenvalues of the sample covariance matrix are small enough to be removed by adding a noise term to the diagonal of the matrix. The mapping is extended to regions of poorer data coverage by applying a smoothed covariance matrix obtained by spatially averaging the sample covariance matrix. This approach estimates a stable covariance matrix of surface currents for regions with the intermittent radar coverage. An additional benefit is the removal of baseline errors that often exist between two radar sites. The covariance matrices and the correlation functions of the surface currents are exponential in space rather than Gaussian, as is often assumed in the objective mapping of oceanographic data sets. Patterns in the decorrelation length scale provide the variabilities of surface currents and the insights on the influence of topographic features (bathymetry and headlands). The objective mapping approach presented herein lends itself to various applications, including the Lagrangian transport estimates, dynamic analysis through divergence and vorticity of current vectors, and statistical models of surface currents.

  1. Mapping impervious surface type and sub-pixel abundance using hyperion hyperspectral imagery

    USGS Publications Warehouse

    Falcone, J.A.; Gomez, R.

    2005-01-01

    Impervious surfaces have been identified as an important and quantifiable indicator of environmental degradation in urban settings. A number of research efforts have been directed at mapping impervious surface type using multispectral imagery. To date, however, no studies have compared equivalent techniques using multispectral and hyperspectral imagery to that end. In this study, data from NASA's 220-channel Hyperion instrument were used to: a) delineate three types of impervious surface, and b) map sub-pixel percent abundance for a study site near Washington, D.C., USA. The results were compared with the results of similar methods using same-spatial-resolution Landsat ETM+ data for mapping impervious surface type, and with the results of the U.S. Geological Survey's National Land Cover Data (NLCD) 2001 impervious surface data layer, which is derived from Landsat and high-resolution Ikonos data. The accuracy of discriminating impervious surface type using Hyperion data was assessed at 88% versus Landsat at 59%. The sub-pixel percent impervious map corresponded well with the NLCD 2001; impervious surface in the study area was calculated at 29.3% for NLCD 2001 and 28.4% for the Hyperion-derived layer. The results suggest that fairly simple techniques using hyperspectral data are effective for quantifying impervious surface type, and that high-spectral- resolution imagery may be a good alternative to high-spatial-resolution data.

  2. Analysis of Temperature Maps of Selected Dawn Data Over the Surface of Vesta

    NASA Technical Reports Server (NTRS)

    Tosi, F.; Capria, M. T.; DeSanctis, M. C.; Palomba, E.; Grassi, D.; Capaccioni, F.; Ammannito, E.; Combe, J.-Ph.; Sunshine, J. M.; McCord, T. B.; Li, Y.-Y.; Titus, T. N.; Russell, C. T.; Raymond, C. A.; Mittlefehldt, D. W.; Toplis, M. J.; Forni, O.; Sykes, M. V.

    2012-01-01

    The thermal behavior of areas of unusual albedo at the surface of Vesta can be related to physical properties that may provide some information about the origin of those materials. Dawn s Visible and Infrared Mapping Spectrometer (VIR) [1] hyperspectral cubes can be used to retrieve surface temperatures. Due to instrumental constraints, high accuracy is obtained only if temperatures are greater than 180 K. Bright and dark surface materials on Vesta are currently investigated by the Dawn team [e.g., 2 and 3 respectively]. Here we present temperature maps of several local-scale features that were observed by Dawn under different illumination conditions and different local solar times.

  3. Titan's Surface Temperatures Maps from Cassini - CIRS Observations

    NASA Astrophysics Data System (ADS)

    Cottini, Valeria; Nixon, C. A.; Jennings, D. E.; Anderson, C. M.; Samuelson, R. E.; Irwin, P. G. J.; Flasar, F. M.

    2009-09-01

    The Cassini Composite Infrared Spectrometer (CIRS) observations of Saturn's largest moon, Titan, are providing us with the ability to detect the surface temperature of the planet by studying its outgoing radiance through a spectral window in the thermal infrared at 19 μm (530 cm-1) characterized by low opacity. Since the first acquisitions of CIRS Titan data the instrument has gathered a large amount of spectra covering a wide range of latitudes, longitudes and local times. We retrieve the surface temperature and the atmospheric temperature profile by modeling proper zonally averaged spectra of nadir observations with radiative transfer computations. Our forward model uses the correlated-k approximation for spectral opacity to calculate the emitted radiance, including contributions from collision induced pairs of CH4, N2 and H2, haze, and gaseous emission lines (Irwin et al. 2008). The retrieval method uses a non-linear least-squares optimal estimation technique to iteratively adjust the model parameters to achieve a spectral fit (Rodgers 2000). We show an accurate selection of the wide amount of data available in terms of footprint diameter on the planet and observational conditions, together with the retrieved results. Our results represent formal retrievals of surface brightness temperatures from the Cassini CIRS dataset using a full radiative transfer treatment, and we compare to the earlier findings of Jennings et al. (2009). In future, application of our methodology over wide areas should greatly increase the planet coverage and accuracy of our knowledge of Titan's surface brightness temperature. References: Irwin, P.G.J., et al.: "The NEMESIS planetary atmosphere radiative transfer and retrieval tool" (2008). JQSRT, Vol. 109, pp. 1136-1150, 2008. Rodgers, C. D.: "Inverse Methods For Atmospheric Sounding: Theory and Practice". World Scientific, Singapore, 2000. Jennings, D.E., et al.: "Titan's Surface Brightness Temperatures." Ap. J. L., Vol. 691, pp. L103-L

  4. Mapping the body surface temperature of cattle by infrared thermography.

    PubMed

    Salles, Marcia Saladini Vieira; da Silva, Suelen Corrêa; Salles, Fernando André; Roma, Luiz Carlos; El Faro, Lenira; Bustos Mac Lean, Priscilla Ayleen; Lins de Oliveira, Celso Eduardo; Martello, Luciane Silva

    2016-12-01

    Infrared thermography (IRT) is an alternative non-invasive method that has been studied as a tool for identifying many physiological and pathological processes related to changes in body temperature. The objective of the present study was to evaluate the body surface temperature of Jersey dairy cattle in a thermoneutral environment in order to contribute to the determination of a body surface temperature pattern for animals of this breed in a situation of thermal comfort. Twenty-four Jersey heifers were used over a period of 35 days at APTA Brazil. Measurements were performed on all animals, starting with the physiological parameters. Body surface temperature was measured by IRT collecting images in different body regions: left and right eye area, right and left eye, caudal left foreleg, cranial left foreleg, right and left flank, and forehead. High correlations were observed between temperature and humidity index (THI) and right flank, left flank and forehead temperatures (0.85, 0.81, and 0.81, respectively). The IRT variables that exhibited the five highest correlation coefficients in principal component 1 were, in decreasing order: forehead (0.90), right flank (0.87), left flank (0.84), marker 1 caudal left foreleg (0.83), marker 2 caudal left foreleg (0.74). The THI showed a high correlation coefficient (0.88) and moderate to low correlations were observed for the physiological variables rectal temperature (0.43), and respiratory frequency (0.42). The thermal profile obtained indicates a surface temperature pattern for each region studied in a situation of thermal comfort and may contribute to studies investigating body surface temperature. Among the body regions studied, IRT forehead temperature showed the highest association with rectal temperature, and forehead and right and left flank temperatures are strongly associated with THI and may be adopted in future studies on thermoregulation and body heat production.

  5. Multispectral mapping of the lunar surface using groundbased telescopes

    NASA Technical Reports Server (NTRS)

    Mccord, T. B.; Pieters, C.; Feirberg, M. A.

    1976-01-01

    Images of the lunar surface were obtained at several wavelengths using a silicon vidicon imaging system and groundbased telescopes. These images were recorded and processed in digital form so that quantitative information is preserved. The photometric precision of the images is shown to be better than 1 percent. Ratio images calculated by dividing images obtained at two wavelengths (0.40/0.56 micrometer) and 0.95/0.56 micrometer are presented for about 50 percent of the lunar frontside. Spatial resolution is about 2 km at the sub-earth point. A complex of distinct units is evident in the images. Earlier work with the reflectance spectrum of lunar materials indicates that for the most part these units are compositionally distinct. Digital images of this precision are extremely useful to lunar geologists in disentangling the history of the lunar surface.

  6. High-resolution Elemental Mapping of the Lunar Surface

    NASA Technical Reports Server (NTRS)

    Edwards, Bradley C.; Ameduri, Frank; Bloch, Jeffrey J.; Priedhorsky, William C.; Roussel-Dupre, Diane; Smith, Barham W.

    1992-01-01

    New instruments and missions are being proposed to study the lunar surface as a result of the resurgence of interest in returning to the Moon. One instrument recently proposed is similar in concept to the x-ray fluorescence detectors flown on Apollo, but utilizes fluorescence from the L- and M-shells rather than the K-shell. This soft X-Ray Flourescence Imager (XRFI) is discussed.

  7. Towards Mapping the Ocean Surface Topography at 1 km Resolution

    NASA Technical Reports Server (NTRS)

    Fu, Lee-Lueng; Rodriquez, Ernesto

    2006-01-01

    We propose to apply the technique of synthetic aperture radar interferometry to the measurement of ocean surface topography at spatial resolution approaching 1 km. The measurement will have wide ranging applications in oceanography, hydrology, and marine geophysics. The oceanographic and related societal applications are briefly discussed in the paper. To meet the requirements for oceanographic applications, the instrument must be flown in an orbit with proper sampling of ocean tides.

  8. Mapping visual cortex in monkeys and humans using surface-based atlases

    NASA Technical Reports Server (NTRS)

    Van Essen, D. C.; Lewis, J. W.; Drury, H. A.; Hadjikhani, N.; Tootell, R. B.; Bakircioglu, M.; Miller, M. I.

    2001-01-01

    We have used surface-based atlases of the cerebral cortex to analyze the functional organization of visual cortex in humans and macaque monkeys. The macaque atlas contains multiple partitioning schemes for visual cortex, including a probabilistic atlas of visual areas derived from a recent architectonic study, plus summary schemes that reflect a combination of physiological and anatomical evidence. The human atlas includes a probabilistic map of eight topographically organized visual areas recently mapped using functional MRI. To facilitate comparisons between species, we used surface-based warping to bring functional and geographic landmarks on the macaque map into register with corresponding landmarks on the human map. The results suggest that extrastriate visual cortex outside the known topographically organized areas is dramatically expanded in human compared to macaque cortex, particularly in the parietal lobe.

  9. Developing Coastal Surface Roughness Maps Using ASTER and QuickBird Data Sources

    NASA Technical Reports Server (NTRS)

    Spruce, Joe; Berglund, Judith; Davis, Bruce

    2006-01-01

    This viewgraph presentation regards one element of a larger project on the integration of NASA science models and data into the Hazards U.S. Multi-Hazard (HAZUS-MH) Hurricane module for hurricane damage and loss risk assessment. HAZUS-MH is a decision support tool being developed by the National Institute of Building Sciences for the Federal Emergency Management Agency (FEMA). It includes the Hurricane Module, which employs surface roughness maps made from National Land Cover Data (NLCD) maps to estimate coastal hurricane wind damage and loss. NLCD maps are produced and distributed by the U.S. Geological Survey. This presentation discusses an effort to improve upon current HAZUS surface roughness maps by employing ASTER multispectral classifications with QuickBird "ground reference" imagery.

  10. Waste-surface mapping of the Fernald K-65 silos using a structured light measurement system

    SciTech Connect

    Burks, B.L.; DePiero, F.W.; Dinkins, M.A.; Rowe, J.C.; Selleck, C.B.; Jacoboski, D.L.

    1992-10-01

    A remotely operated surface-mapping measurement system was developed by the Robotics & Process Systems Division at Oak Ridge National Laboratory for use in the K-65 waste-storage silos at Fernald, Ohio. The mapping system used three infrared line-generating laser diodes as illumination sources and three high-resolution, low-lux, calibrated, black-and-white, charge-coupled-device video cameras as receivers. These components were combined to form structured light source range and direction sensors with six different possible emitter-receiver pairs. A technology demonstration and predeployment tests were performed at Fernald using the empty Silo 4 into which was placed rectangular objects of known dimensions. These objects were scanned by the structured light sources to demonstrate functionality and verify that the system was giving sufficiently accurate range data in three dimensions. The structured light sources were deployed in Silos 1 and 2 to scan the waste surfaces. The resulting data were merged to create three-dimensional maps of those surfaces. A bentonite clay cap was placed over the waste surfaces and surface maps were obtained. The change in surface height before and after bentonite addition was utilized as a measure of clay cap thickness.

  11. Waste-surface mapping of the Fernald K-65 silos using a structured light measurement system

    SciTech Connect

    Burks, B.L.; DePiero, F.W.; Dinkins, M.A.; Rowe, J.C. ); Selleck, C.B. ); Jacoboski, D.L. )

    1992-10-01

    A remotely operated surface-mapping measurement system was developed by the Robotics Process Systems Division at Oak Ridge National Laboratory for use in the K-65 waste-storage silos at Fernald, Ohio. The mapping system used three infrared line-generating laser diodes as illumination sources and three high-resolution, low-lux, calibrated, black-and-white, charge-coupled-device video cameras as receivers. These components were combined to form structured light source range and direction sensors with six different possible emitter-receiver pairs. A technology demonstration and predeployment tests were performed at Fernald using the empty Silo 4 into which was placed rectangular objects of known dimensions. These objects were scanned by the structured light sources to demonstrate functionality and verify that the system was giving sufficiently accurate range data in three dimensions. The structured light sources were deployed in Silos 1 and 2 to scan the waste surfaces. The resulting data were merged to create three-dimensional maps of those surfaces. A bentonite clay cap was placed over the waste surfaces and surface maps were obtained. The change in surface height before and after bentonite addition was utilized as a measure of clay cap thickness.

  12. A hydrogeological study of the confined aquifers below the Boom Clay in NE-Belgium: combining a piezometric analysis with groundwater modelling

    NASA Astrophysics Data System (ADS)

    Vandersteen, Katrijn; Gedeon, Matej

    2013-04-01

    For more than 35 years, SCKCEN has been investigating the possibility of high-level and/or long-lived radioactive waste disposal in the Boom Clay in north-eastern Belgium. This research, defined in the long term management programme for high-level and/or long-lived waste of ONDRAF/NIRAS, includes studying the regional hydrogeology of the aquifer systems surrounding the Boom Clay. In this context, a hydrogeological study of the confined aquifers below the Boom Clay was performed. To properly address the conceptual uncertainties related to the poorly characterized domain featuring large uncertainty in the forcing data, a combination of a piezometric data analysis and hydrogeological modelling was used. The study area represents the confined part of the groundwater system located stratigraphically below the Boom Clay in NE-Belgium. This so-called deep aquifer system includes, with increasing depth, parts of the Oligocene aquifer, the Bartoon aquitard system and the Ledo-Paniselian-Brusselian aquifer. Due to the considerable pumping from these aquifers in combination with a limited recharge to the deep aquifer system, a gradual decrease in groundwater levels has been observed in more than 30-year piezometric records. The analysis of the piezometry of the confined deep aquifer system allowed gaining more insight on the system response to the intensive pumping. Since the Oligocene aquifer has a significantly lower permeability compared to the Ledo-Paniselian-Brusselian aquifer, the Oligocene pumping triggers only local effects on groundwater levels. Hence, the regional effects (constant decrease of groundwater levels) in the Oligocene aquifer are presumably caused by pumping in the Ledo-Paniselian-Brusselian aquifer, whereby the hydraulically isolating Maldegem Formation (Bartoon aquitard) dampens these effects. The amount of this dampening is given by the spatial distribution of the hydraulic properties of the Maldegem Formation and/or its variable thickness. For the

  13. Mapping the surface of the dwarf planet Makemake

    NASA Astrophysics Data System (ADS)

    Perna, D.; Merlin, F.; Ieva, S.; Barucci, M. A.; Dotto, E.; Fornasier, S.; Mazzotta Epifani, E.

    2012-09-01

    Makemake is the third largest dwarf planet (and trans-neptunian object) so far discovered in the Solar System, after Eris and Pluto. However, despite of its large dimensions, previous observations of Makemake have been scarce and sometimes not satisfactory (e.g., due to low S/N), thus it is by far the less investigated object among the largest TNOs. Hence we used the TNG telescope to carry out, for the first time, high S/N visible and near infrared spectroscopy at different rotational phases, in order to assess the surface composition of this body, as well as the presence of the hypothesized inhomogeneities. The obtained data are also important to put constraints on processes like space weathering, cryovolcanism, atmospheric escape, etc..

  14. Design of 3D scanner for surface contour mapping by ultrasonic sensor

    NASA Astrophysics Data System (ADS)

    Munir, Muhammad Miftahul; Billah, Mohammad Aziz; Surachman, Arif; Budiman, Maman; Khairurrijal

    2015-04-01

    Surface mapping systems have attracted great attention due to their potential applications in many areas. In this paper, a simple 3D scanner based on ultrasonic sensor was designed for mapping a contour of object surface. The scanner using an SRF02 ultrasonic sensor, a microcontroller and radio frequency (RF) module to collect coordinates of object surface (point cloud), and sent data to computer. The point cloud collection process was performed by moving two ultrasonic sensors in y and x directions. Both sensors measure a distance from an object surface to a reference point of each sensor. The measurement results represent the point cloud of object surface and the data will be sent to computer via RF module. The point cloud then converted to 3D model using MATLAB. It was found that the object contours can be reconstructed very well by the developed 3D scanner system.

  15. Surface Rupture Map of the 2002 M7.9 Denali Fault Earthquake, Alaska: Digital Data

    USGS Publications Warehouse

    Haeussler, Peter J.

    2009-01-01

    The November 3, 2002, Mw7.9 Denali Fault earthquake produced about 340 km of surface rupture along the Susitna Glacier Thrust Fault and the right-lateral, strike-slip Denali and Totschunda Faults. Digital photogrammetric methods were primarily used to create a 1:500-scale, three-dimensional surface rupture map, and 1:6,000-scale aerial photographs were used for three-dimensional digitization in ESRI's ArcMap GIS software, using Leica's StereoAnalyst plug in. Points were digitized 4.3 m apart, on average, for the entire surface rupture. Earthquake-induced landslides, sackungen, and unruptured Holocene fault scarps on the eastern Denali Fault were also digitized where they lay within the limits of air photo coverage. This digital three-dimensional fault-trace map is superior to traditional maps in terms of relative and absolute accuracy, completeness, and detail and is used as a basis for three-dimensional visualization. Field work complements the air photo observations in locations of dense vegetation, on bedrock, or in areas where the surface trace is weakly developed. Seventeen km of the fault trace, which broke through glacier ice, were not digitized in detail due to time constraints, and air photos missed another 10 km of fault rupture through the upper Black Rapids Glacier, so that was not mapped in detail either.

  16. Comparison of Geostatistical Kriging Algorithms for Intertidal Surface Sediment Facies Mapping with Grain Size Data

    PubMed Central

    2014-01-01

    This paper compares the predictive performance of different geostatistical kriging algorithms for intertidal surface sediment facies mapping using grain size data. Indicator kriging, which maps facies types from conditional probabilities of predefined facies types, is first considered. In the second approach, grain size fractions are first predicted using cokriging and the facies types are then mapped. As grain size fractions are compositional data, their characteristics should be considered during spatial prediction. For efficient prediction of compositional data, additive log-ratio transformation is applied before cokriging analysis. The predictive performance of cokriging of the transformed variables is compared with that of cokriging of raw fractions in terms of both prediction errors of fractions and facies mapping accuracy. From a case study of the Baramarae tidal flat, Korea, the mapping method based on cokriging of log-ratio transformation of fractions outperformed the one based on cokriging of untransformed fractions in the prediction of fractions and produced the best facies mapping accuracy. Indicator kriging that could not account for the variation of fractions within each facies type showed the worst mapping accuracy. These case study results indicate that the proper processing of grain size fractions as compositional data is important for reliable facies mapping. PMID:24688362

  17. Comparison of geostatistical kriging algorithms for intertidal surface sediment facies mapping with grain size data.

    PubMed

    Park, No-Wook; Jang, Dong-Ho

    2014-01-01

    This paper compares the predictive performance of different geostatistical kriging algorithms for intertidal surface sediment facies mapping using grain size data. Indicator kriging, which maps facies types from conditional probabilities of predefined facies types, is first considered. In the second approach, grain size fractions are first predicted using cokriging and the facies types are then mapped. As grain size fractions are compositional data, their characteristics should be considered during spatial prediction. For efficient prediction of compositional data, additive log-ratio transformation is applied before cokriging analysis. The predictive performance of cokriging of the transformed variables is compared with that of cokriging of raw fractions in terms of both prediction errors of fractions and facies mapping accuracy. From a case study of the Baramarae tidal flat, Korea, the mapping method based on cokriging of log-ratio transformation of fractions outperformed the one based on cokriging of untransformed fractions in the prediction of fractions and produced the best facies mapping accuracy. Indicator kriging that could not account for the variation of fractions within each facies type showed the worst mapping accuracy. These case study results indicate that the proper processing of grain size fractions as compositional data is important for reliable facies mapping.

  18. The use of a genetic algorithm-based search strategy in geostatistics: application to a set of anisotropic piezometric head data

    NASA Astrophysics Data System (ADS)

    Abedini, M. J.; Nasseri, M.; Burn, D. H.

    2012-04-01

    In any geostatistical study, an important consideration is the choice of an appropriate, repeatable, and objective search strategy that controls the nearby samples to be included in the location-specific estimation procedure. Almost all geostatistical software available in the market puts the onus on the user to supply search strategy parameters in a heuristic manner. These parameters are solely controlled by geographical coordinates that are defined for the entire area under study, and the user has no guidance as to how to choose these parameters. The main thesis of the current study is that the selection of search strategy parameters has to be driven by data—both the spatial coordinates and the sample values—and cannot be chosen beforehand. For this purpose, a genetic-algorithm-based ordinary kriging with moving neighborhood technique is proposed. The search capability of a genetic algorithm is exploited to search the feature space for appropriate, either local or global, search strategy parameters. Radius of circle/sphere and/or radii of standard or rotated ellipse/ellipsoid are considered as the decision variables to be optimized by GA. The superiority of GA-based ordinary kriging is demonstrated through application to the Wolfcamp Aquifer piezometric head data. Assessment of numerical results showed that definition of search strategy parameters based on both geographical coordinates and sample values improves cross-validation statistics when compared with that based on geographical coordinates alone. In the case of a variable search neighborhood for each estimation point, optimization of local search strategy parameters for an elliptical support domain—the orientation of which is dictated by anisotropic axes—via GA was able to capture the dynamics of piezometric head in west Texas/New Mexico in an efficient way.

  19. Surface Water and Flood Extent Mapping, Monitoring, and Modeling Products and Services for the SERVIR Regions

    NASA Technical Reports Server (NTRS)

    Anderson, Eric

    2016-01-01

    SERVIR is a joint NASA - US Agency for International Development (USAID) project to improve environmental decision-making using Earth observations and geospatial technologies. A common need identified among SERVIR regions has been improved information for disaster risk reduction and in specific surface water and flood extent mapping, monitoring and forecasting. Of the 70 SERVIR products (active, complete, and in development), 4 are related to surface water and flood extent mapping, monitoring or forecasting. Visit http://www.servircatalog.net for more product details.

  20. [Optical mapping of chronotopography of excitation of the frog heart ventricle epicardial surface in sinus rhythm].

    PubMed

    abramochkin, D V; Rozenshtraukh, L V

    2008-04-01

    Two points of early activation were shown on the surface of the frog Rana temporaria ventricle using optical mapping technique. These points are located on the left and right ventricular surface at equal distance from apex and base of the ventricle. The excitation approaches to epicardial ventricular surface at these points, and then it spreads all over the surface. Such pattern of epicardial activation is also shown in mammals where it is related to conduction system functioning. Thus, the precursor of conduction system seems to exist in the frog ventricle, too.

  1. Compositional Mapping of the Surface and Interior of Mammalian Cells at Submicrometer Resolution

    PubMed Central

    Szakal, Christopher; Narayan, Kedar; Fu, Jing; Lefman, Jonathan; Subramaniam, Sriram

    2016-01-01

    We present progress toward imaging of chemical species within intact mammalian cells using secondary ion mass spectrometry, including the simultaneous mapping of subcellular elemental and molecular species along with intrinsic membrane-specific cellular markers. Results from imaging both the cell surface and cell interior exposed by site-specific focused ion beam milling demonstrate that in-plane resolutions of approximately 400–500 nm can be achieved. The results from mapping cell surface phosphatidylcholine and several other molecular ions present in the cells establish that spatially resolved chemical signatures of individual cells can be derived from novel multivariate analysis and classification of the molecular images obtained at different m/z ratios. The methods we present here for specimen preparation and chemical imaging of cell interiors provide the foundation for obtaining 3D molecular maps of unstained mammalian cells, with particular relevance for probing the subcellular distributions of small molecules, such as drugs and metabolites. PMID:21268648

  2. Mapping extent and change in surface mines within the United States for 2001 to 2006

    USGS Publications Warehouse

    Soulard, Christopher E.; Acevedo, William; Stehman, Stephen V.; Parker, Owen P.

    2016-01-01

    A complete, spatially explicit dataset illustrating the 21st century mining footprint for the conterminous United States does not exist. To address this need, we developed a semi-automated procedure to map the country's mining footprint (30-m pixel) and establish a baseline to monitor changes in mine extent over time. The process uses mine seed points derived from the U.S. Energy Information Administration (EIA), U.S. Geological Survey (USGS) Mineral Resources Data System (MRDS), and USGS National Land Cover Dataset (NLCD) and recodes patches of barren land that meet a “distance to seed” requirement and a patch area requirement before mapping a pixel as mining. Seed points derived from EIA coal points, an edited MRDS point file, and 1992 NLCD mine points were used in three separate efforts using different distance and patch area parameters for each. The three products were then merged to create a 2001 map of moderate-to-large mines in the United States, which was subsequently manually edited to reduce omission and commission errors. This process was replicated using NLCD 2006 barren pixels as a base layer to create a 2006 mine map and a 2001–2006 mine change map focusing on areas with surface mine expansion. In 2001, 8,324 km2 of surface mines were mapped. The footprint increased to 9,181 km2 in 2006, representing a 10·3% increase over 5 years. These methods exhibit merit as a timely approach to generate wall-to-wall, spatially explicit maps representing the recent extent of a wide range of surface mining activities across the country. 

  3. Mapping impervious surfaces using object-oriented classification in a semiarid urban region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mapping the expansion of impervious surfaces in urbanizing areas is important for monitoring and understanding the hydrologic impacts of land development. The most common approach using spectral vegetation indices, however, is difficult in arid and semiarid environments where vegetation is sparse an...

  4. Evaluation of orthomosics and digital surface models derived from aerial imagery for crop mapping

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Orthomosics derived from aerial imagery acquired by consumer-grade cameras have been used for crop mapping. However, digital surface models (DSM) derived from aerial imagery have not been evaluated for this application. In this study, a novel method was proposed to extract crop height from DSM and t...

  5. Surface Emissivity Maps for Use in Satellite Retrievals of Longwave Radiation

    NASA Technical Reports Server (NTRS)

    Wilber, Anne C.; Kratz, David P.; Gupta, Shashi K.

    1999-01-01

    Accurate accounting of surface emissivity is essential for the retrievals of surface temperature from remote sensing measurements, and for the computations of longwave (LW) radiation budget of the Earth?s surface. Past studies of the above topics assumed that emissivity for all surface types, and across the entire LW spectrum is equal to unity. There is strong evidence, however, that emissivity of many surface materials is significantly lower than unity, and varies considerably across the LW spectrum. We have developed global maps of surface emissivity for the broadband LW region, the thermal infrared window region (8-12 micron), and 12 narrow LW spectral bands. The 17 surface types defined by the International Geosphere Biosphere Programme (IGBP) were adopted as such, and an additional (18th) surface type was introduced to represent tundra-like surfaces. Laboratory measurements of spectral reflectances of 10 different surface materials were converted to corresponding emissivities. The 10 surface materials were then associated with 18 surface types. Emissivities for the 18 surface types were first computed for each of the 12 narrow spectral bands. Emissivities for the broadband and the window region were then constituted from the spectral band values by weighting them with Planck function energy distribution.

  6. Retrieval and Mapping of Soil Texture Based on Land Surface Diurnal Temperature Range Data from MODIS.

    PubMed

    Wang, De-Cai; Zhang, Gan-Lin; Zhao, Ming-Song; Pan, Xian-Zhang; Zhao, Yu-Guo; Li, De-Cheng; Macmillan, Bob

    2015-01-01

    Numerous studies have investigated the direct retrieval of soil properties, including soil texture, using remotely sensed images. However, few have considered how soil properties influence dynamic changes in remote images or how soil processes affect the characteristics of the spectrum. This study investigated a new method for mapping regional soil texture based on the hypothesis that the rate of change of land surface temperature is related to soil texture, given the assumption of similar starting soil moisture conditions. The study area was a typical flat area in the Yangtze-Huai River Plain, East China. We used the widely available land surface temperature product of MODIS as the main data source. We analyzed the relationships between the content of different particle soil size fractions at the soil surface and land surface day temperature, night temperature and diurnal temperature range (DTR) during three selected time periods. These periods occurred after rainfalls and between the previous harvest and the subsequent autumn sowing in 2004, 2007 and 2008. Then, linear regression models were developed between the land surface DTR and sand (> 0.05 mm), clay (< 0.001 mm) and physical clay (< 0.01 mm) contents. The models for each day were used to estimate soil texture. The spatial distribution of soil texture from the studied area was mapped based on the model with the minimum RMSE. A validation dataset produced error estimates for the predicted maps of sand, clay and physical clay, expressed as RMSE of 10.69%, 4.57%, and 12.99%, respectively. The absolute error of the predictions is largely influenced by variations in land cover. Additionally, the maps produced by the models illustrate the natural spatial continuity of soil texture. This study demonstrates the potential for digitally mapping regional soil texture variations in flat areas using readily available MODIS data.

  7. Pickup Ion Mass Spectrometry for Surface Bounded Exospheres and Composition Mapping of Lunar and Planetary Surfaces

    NASA Technical Reports Server (NTRS)

    Keller, J. W.; Zurbuchen, T. H.; Baragiola, R. A.; Cassidy, T. A.; Chornay, D. J.; Collier, M. R.; Hartle, R. E.; Johnson, R. E.; Killen, R. M.; Koehn, P.

    2005-01-01

    Many of the small to medium sized objects in the solar system can be characterized as having surface bounded exospheres, or atmospheres so tenuous that scale lengths for inter-particle collisions are much larger than the dimensions of the objects. The atmospheres of these objects are the product of their surfaces, both the surface composition and the interactions that occur on them and also their interiors when gases escape from there. Thus by studying surface bounded exospheres it is possible to develop insight into the composition and processes that are taking place on the surface and interiors of these objects. The Moon and Mercury are two examples of planetary bodies with surface bounded exospheres that have been studied through spectroscopic observations of sodium, potassium, and, on the moon, mass spectrometric measurements of lunar gases such as argon and helium.

  8. Development of Surface Wave Dispersion and Attenuation Maps and Improved Methods for Measuring Surface Waves

    DTIC Science & Technology

    2008-05-30

    use a similar technique with a narrower kernel that they believe to be more representative of realistic surface waves. Spetzler et al. (2001, 2002...Nor and KNET. We measured surface wave spectral amplitudes from the calculations using the same techniques used to measure observed surface waves...The Born approximation techniques discussed in section 3 provide a straightforward, but approximate, way to incorporate scattering and diffraction

  9. High Resolution Mapping of the Impermeable Surfaces of Barnstable County, Cape Cod and their Relationship to Water Quality

    NASA Astrophysics Data System (ADS)

    Stone, T.; Fiske, G.; Schlesinger, P.

    2003-12-01

    We have developed several impermeable surface maps for all Cape Cod (Barnstable County) to help assess the contribution of paved and other impermeable surfaces to declines in local and regional water quality. These maps have been assembled with the cooperation of many town planning departments, the Cape Cod National Seashore, Mass Military Reservation, the Cape Cod Commission, the Association to Preserve Cape Cod (APCC) and from IKONOS data. The map are being used to predict where new impermeable surface will occur, define current and future hotspots of non-point pollution, and to map the relationships of impermeable surfaces to the zones of contribution (ZOC) of municipal wells. The maps are also used to define the percentage of impermeable surfaces in buffer zones around ponds and estuaries. Combining these data with census data on housing and population density allows us to define the importance of impervious surface as minor or major factors in water pollution.

  10. Map showing surface ruptures associated with the Mammoth Lakes, California, earthquakes of May 1980

    USGS Publications Warehouse

    Clark, M.M.; Yount, J.C.; Vaughn, P.R.; Zepeda, R.L.

    1982-01-01

    This map shows surface ruptures associated with the M 6 Mammoth Lakes earthquakes of May 25-27, 1980 (Sherburne, 1980). The ruptures were mapped during USGS field investigations May 28 to June 4 and July 14-19, 1980. The map also includes some of the ruptures recorded by California Division of Mines and Geology investigators May 26-31, June 26-27, and July 7-11, 1980 (Taylor and Bryant, 1980). Because most of the surface ruptures developed in either unconsolidated pumice, alluvium, or till (and many were on slopes of scarps created by earlier faulting), wind, rain and animals quickly erased many of the ruptures. In places, the minimum detectable slip was 3-10 mm. Thus the lines on the map do not record all of the ruptures that formed at the time of the earthquake. Many of the areas were we show gaps between lines on the map probably had cracks originally. 

  11. Study of an Open Web Mapping Service for ESA's Planetary Surface Data Sets

    NASA Astrophysics Data System (ADS)

    Manaud, N.; Hempen, B.; Heather, D.; Salgado, J.; Osuna, P.; Frigeri, A.

    2011-10-01

    The aim of this study is to understand how open GIS technology and standards can be used to manage, process, and stream the geospatial content of the PSA archive across the Internet into existing mapping applications and software libraries. To support this goal, we will design and develop an OGC-compliant web mapping service prototype providing a specific interface for client applications to search, process, retrieve and visualise the Mars Express/ OMEGA mapping spectrometer data [6] currently available in the PSA. The interface will be designed to accommodate future needs as additional planetary surface data become available or additional functionalities are required. It is anticipated that this web mapping service will provide a practical open framework contributing to the international efforts to define an extension of the PDAP data model for planetary surface data [7][8]. Although it has been demonstrated that OGC web mapping standards can be applied to the planetary science domain, they have limitations that currently prevent the use of their full capability. This study will document such limitations and feed potential recommendations into the Planetary OGC Interoperability Experiment (Planetary IE), an international initiative coordinated by USGS Astrogeology Science Center to ensure that the planetary community will properly leverage future OGC specifications [9].

  12. Impervious Surface Area Mapping using Landsat Imagery: Applications to Hydrology and Land Use Change Monitoring

    NASA Astrophysics Data System (ADS)

    Smith, A.; Goetz, S. J.; Mazzacato, M. E.; Jantz, C.; Wright, R.

    2002-12-01

    Impervious surfaces include rooftops, roads, parking lots and other areas that are impermeable to moisture. As the amount of built environment around urban areas has increased, it has been widely recognized that more impervious surface area (ISA) results in greater volume and intensity of stream flow, which can degrade stream health and require expensive modifications to flood control structures. Other effects include increased urban "heat island" influences and changes in local weather. If impervious areas could be accurately mapped using satellite imagery, it would provide valuable input to many applications, from hydrologic modeling to land use planning. We have developed a method to map subpixel ISA with Landsat Thematic Mapper (TM) imagery and classification - regression tree algorithms. This approach provides highly accurate (90+ percent) maps of ISA, but also permits estimation of the proportion of each cell occupied by impervious materials (between 0-100 percent). We report on a recently completed a map of ISA for the entire 163,000 km2 Chesapeake Bay watershed, a region of highly altered land cover and rapid land use change. We also report on the mapping of change patterns, indicated by ISA changes between 1986 - 2001, in an 18,000 km2 area centered on Baltimore - Washington, D.C. We review the methods, issues, technical challenges, results, accuracy, and advantages of this approach, and provide an overview of various applications for which the products are currently being used.

  13. Phased-array ultrasonic surface contour mapping system and method for solids hoppers and the like

    DOEpatents

    Fasching, George E.; Smith, Jr., Nelson S.

    1994-01-01

    A real time ultrasonic surface contour mapping system is provided including a digitally controlled phased-array of transmitter/receiver (T/R) elements located in a fixed position above the surface to be mapped. The surface is divided into a predetermined number of pixels which are separately scanned by an arrangement of T/R elements by applying phase delayed signals thereto that produce ultrasonic tone bursts from each T/R that arrive at a point X in phase and at the same time relative to the leading edge of the tone burst pulse so that the acoustic energies from each T/R combine in a reinforcing manner at point X. The signals produced by the reception of the echo signals reflected from point X back to the T/Rs are also delayed appropriately so that they add in phase at the input of a signal combiner. This combined signal is then processed to determine the range to the point X using density-corrected sound velocity values. An autofocusing signal is developed from the computed average range for a complete scan of the surface pixels. A surface contour map is generated in real time form the range signals on a video monitor.

  14. Generalized potentiometric-surface map of the High Plains aquifer in Wyoming, 1981

    USGS Publications Warehouse

    Avery, Charles; Pettijohn, Robert A.

    1984-01-01

    A potentiometric-surface map shows the general configuration of the water surface for the High Plains Aquifer, which is composed of Oligocene age and younger rocks in southeastern Wyoming. The potentiometric contours are shown at 100-foot intervals on a map at a scale of 1:250,000. The High Plains Aquifer in Wyoming underlies an area of 8,190 square miles and geologically consists of the White River Formation of Oligocene age, the Arikaree Formation of early Miocene age, the Ogallala Formation of late Miocene age, and alluvial deposits of Quaternary age. The altitude of the potentiometric surface declines from about 7 ,100 feet in southwestern Laramie County to about 4,100 feet in eastern Goshen County. Typically, the slope is between 20 and 30 feet per mile; the general direction of flow is eastward. (USGS)

  15. Surface materials map of Afghanistan: iron-bearing minerals and other materials

    USGS Publications Warehouse

    King, Trude V.V.; Kokaly, Raymond F.; Hoefen, Todd M.; Dudek, Kathleen B.; Livo, Keith E.

    2012-01-01

    This map shows the distribution of selected iron-bearing minerals and other materials derived from analysis of HyMap imaging spectrometer data of Afghanistan. Using a NASA (National Aeronautics and Space Administration) WB-57 aircraft flown at an altitude of ~15,240 meters or ~50,000 feet, 218 flight lines of data were collected over Afghanistan between August 22 and October 2, 2007. The HyMap data were converted to apparent surface reflectance, then further empirically adjusted using ground-based reflectance measurements. The reflectance spectrum of each pixel of HyMap data was compared to the spectral features of reference entries in a spectral library of minerals, vegetation, water, ice, and snow. This map shows the spatial distribution of iron-bearing minerals and other materials having diagnostic absorptions at visible and near-infrared wavelengths. These absorptions result from electronic processes in the minerals. Several criteria, including (1) the reliability of detection and discrimination of minerals using the HyMap spectrometer data, (2) the relative abundance of minerals, and (3) the importance of particular minerals to studies of Afghanistan's natural resources, guided the selection of entries in the reference spectral library and, therefore, guided the selection of mineral classes shown on this map. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated. Minerals having similar spectral features were less easily discriminated, especially where the minerals were not particularly abundant and (or) where vegetation cover reduced the absorption strength of mineral features. Complications in reflectance calibration also affected the detection and identification of minerals.

  16. Surface materials map of Afghanistan: carbonates, phyllosilicates, sulfates, altered minerals, and other materials

    USGS Publications Warehouse

    Kokaly, Raymond F.; King, Trude V.V.; Hoefen, Todd M.; Dudek, Kathleen B.; Livo, Keith E.

    2012-01-01

    This map shows the distribution of selected carbonates, phyllosilicates, sulfates, altered minerals, and other materials derived from analysis of HyMap imaging spectrometer data of Afghanistan. Using a NASA (National Aeronautics and Space Administration) WB-57 aircraft flown at an altitude of ~15,240 meters or ~50,000 feet, 218 flight lines of data were collected over Afghanistan between August 22 and October 2, 2007. The HyMap data were converted to apparent surface reflectance, then further empirically adjusted using ground-based reflectance measurements. The reflectance spectrum of each pixel of HyMap data was compared to the spectral features of reference entries in a spectral library of minerals, vegetation, water, ice, and snow. This map shows the spatial distribution of minerals that have diagnostic absorption features in the shortwave infrared wavelengths. These absorption features result primarily from characteristic chemical bonds and mineralogical vibrations. Several criteria, including (1) the reliability of detection and discrimination of minerals using the HyMap spectrometer data, (2) the relative abundance of minerals, and (3) the importance of particular minerals to studies of Afghanistan's natural resources, guided the selection of entries in the reference spectral library and, therefore, guided the selection of mineral classes shown on this map. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated. Minerals having similar spectral features were less easily discriminated, especially where the minerals were not particularly abundant and (or) where vegetation cover reduced the absorption strength of mineral features. Complications in reflectance calibration also affected the detection and identification of minerals.

  17. Map showing the potentiometric surface of the Aquia Aquifer, May 19-23, 1980

    USGS Publications Warehouse

    Chapelle, Frank; Drummond, Dave; Curley, Tracey

    1981-01-01

    The map is based on water level measurements made May 19-23, 1980. The well network used included 83 wells which have been screened in the Aquia aquifer (Aquia Formation of Paleocene Age). Highest levels of the potentiometric surface, 20 to 35 feet above sea level, were measured near the outcrop or subcrop of the aquifer in the topographically high areas of Anne Arundel and Prince Georges Counties. The potentiometric surface slopes to the southeast. Four separate and extensive cones of depression have developed in the potentiometric surface in the vicinities of Lexington Park, Leonardtown, Prince Frederick, and Chesapeake Beach. The cones of Leonardtown and Lexington Park seem to be merging. (USGS)

  18. Surface vector mapping of magnetic anomalies over the Moon using Kaguya and Lunar Prospector observations

    NASA Astrophysics Data System (ADS)

    Tsunakawa, Hideo; Takahashi, Futoshi; Shimizu, Hisayoshi; Shibuya, Hidetoshi; Matsushima, Masaki

    2015-06-01

    We have provided preliminary global maps of three components of the lunar magnetic anomaly on the surface applying the surface vector mapping (SVM) method. The data used in the present study consist of about 5 million observations of the lunar magnetic field at 10-45 km altitudes by Kaguya and Lunar Prospector. The lunar magnetic anomalies were mapped at 0.2° equi-distance points on the surface by the SVM method, showing the highest intensity of 718 nT in the Crisium antipodal region. Overall features on the SVM maps indicate that elongating magnetic anomalies are likely to be dominant on the Moon except for the young large basins with the impact demagnetization. Remarkable demagnetization features suggested by previous studies are also recognized at Hertzsprung and Kolorev craters on the farside. These features indicate that demagnetized areas extend to about 1-2 radii of the basins/craters. There are well-isolated central magnetic anomalies at four craters: Leibnitz, Aitken, Jules Verne, and Grimaldi craters. Their magnetic poles through the dipole source approximation suggest occurrence of the polar wander prior to 3.3-3.5 Ga. When compared with high-albedo markings at several magnetic anomalies such as the Reiner Gamma anomalies, three-dimensional structures of the magnetic field on/near the surface are well correlated with high-albedo areas. These results indicate that the global SVM maps are useful for the study of the lunar magnetic anomalies in comparison with various geological and geophysical data.

  19. Precision Thickness Variation Mapping via One-Transducer Ultrasonic High Resolution Profilometry for Sample with Irregular or Rough Surface

    NASA Technical Reports Server (NTRS)

    Roth, Don J. (Inventor)

    1997-01-01

    An apparatus and method for determination of sample thickness and surface depression utilizing ultrasonic pulses. The sample is held in a predetermined position by a support member having a reference surface. Ultrasonic pulses travel through a medium of known velocity propagation and reflect off the reference surface and a sample surface. Time of flight data of surface echoes are converted to distances between sample surfaces to obtain computer-generated thickness profiles and surface mappings.

  20. Precision Thickness Variation Mapping Via One-Transducer Ultrasonic High Resolution Profilometry for Sample With Irregular or Rough Surface

    NASA Technical Reports Server (NTRS)

    Roth, Don J. (Inventor)

    1996-01-01

    An apparatus and method for determination of sample thickness and surface depression utilizing ultrasonic pulses is discussed. The sample is held in a predetermined position by a support member having a reference surface. Ultrasonic pulses travel through a medium of known velocity propagation and reflect off the reference surface and a sample surface. Time of flight data of surface echoes are converted to distances between sample surfaces to obtain computer-generated thickness profiles and surface mappings.

  1. Making global map of the solar surface Br from the HMI vector magnetic field observations

    NASA Astrophysics Data System (ADS)

    Hayashi, K.; Liu, Y.; Sun, X.; Hoeksema, J. T.; Centeno, R.; Barnes, G.; Leka, K. D.

    2013-06-01

    The Helioseismic Magnetic Imager (HMI) has made full-disk vector magnetic field measurements of the Sun with cadence of 12 minutes. The three-component solar surface magnetic field vector data are from the HMI observations with the data process pipeline modules, VFISV (Very Fast Inversion of the Stokes Vector, Borrero et al., 2011) for Milne-Eddington inversion and the minimum-energy disambiguation algorithm (Metcalf 1994, Leka et al, 2009). The models of the global corona and solar wind, such as the PFSS (potential-field source-surface) model and the MHD simulations, often use the maps of solar surface magnetic field, especially the radial component (Br) as the boundary condition. The HMI observation can provide new Br data for these model. Because of weak magnetic signals at the quiet regions of the Sun, the limb darkening, and geometric effects near solar poles, we need to apply an assumption to make a whole-surface map. In this paper, we tested two assumptions for determining Br at weak-field regions. The coronal structures calculated by the PFSS model with the vector-based Br are compared with those with the magnetogram-based Br and the corona observed by the SDO/AIA (Atmospheric Imaging Assembly). In the tested period, CR 2098, the vector-based Br map gives better agreements than the line-of-sight magnetogram data, though we need further investigation for evaluation.

  2. Map showing general chemical quality of surface water in the Richfield Quadrangle, Utah

    USGS Publications Warehouse

    Price, Don

    1980-01-01

    This is one of a series of maps that describe the geology and related natural resources of the Richfield 2° quadrangle, Utah. The purpose of this map is to show the general chemical quality of surface water in the area by ranges of dissolved-solids concentrations.Data used to compile this map were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights. In those areas where little or no surface-water-quality data are available, ranges of dissolved-solids concentrations of the water are inferred on the basis of such factors as geology (Stokes, 1964), precipitation, topography, known ground-water quality, and water uses – all of which affect the chemical quality of surface water.Additional information about the chemical quality of surface water in various parts of the Richfield 2° quadrangle may be found in the following reports: Hahl and Cabell (1965), Hahl and Mundorff (1968), Stephens (1974, 1976), Cruff and Mower (1976), and Cruff(1977)

  3. Study of variability of permittivity and its mapping over lunar surface and subsurface using multisensors datasets

    NASA Astrophysics Data System (ADS)

    Calla, O. P. N.; Mathur, Shubhra; Gadri, Kishan Lal; Jangid, Monika

    2016-12-01

    In the present paper, permittivity maps of equatorial lunar surface are generated using brightness temperature (TB) data obtained from Microwave Radiometer (MRM) of Chang'e-1 and physical temperature (TP) data obtained from Diviner of Lunar Reconnaissance Orbiter (LRO). Here, permittivity mapping is not carried out above 60° latitudes towards the lunar poles due to large anomaly in the physical temperature obtained from the Diviner. Microwave frequencies, which are used to generate these maps are 3 GHz, 7.8 GHz, 19.35 GHz and 37 GHz. Permittivity values are simulated using TB values at these four frequencies. Here, weighted average of physical temperature obtained from Diviner are used to compute permittivity at each microwave frequencies. Longer wavelengths of microwave signals give information of more deeper layers of the lunar surface as compared to smaller wavelength. Initially, microwave emissivity is estimated using TB values from MRM and physical temperature (TP) from Diviner. From estimated emissivity the real part of permittivity (ε), is calculated using Fresnel equations. The permittivity maps of equatorial lunar surface is generated. The simulated permittivity values are normalized with respect to density for easy comparison of simulated permittivity values with the permittivity values of Apollo samples as well as with the permittivity values of Terrestrial Analogue of Lunar Soil (TALS) JSC-1A. Lower value of dielectric constant (ε‧) indicates that the corresponding lunar surface is smooth and doesn't have rough rocky terrain. Thus a future lunar astronaut can use these data to decide proper landing site for future lunar missions. The results of this paper will serve as input to future exploration of lunar surface.

  4. Reactivity mapping with electrochemical gradients for monitoring reactivity at surfaces in space and time.

    PubMed

    Krabbenborg, Sven O; Nicosia, Carlo; Chen, Pengkun; Huskens, Jurriaan

    2013-01-01

    Studying and controlling reactions at surfaces is of great fundamental and applied interest in, among others, biology, electronics and catalysis. Because reaction kinetics is different at surfaces compared with solution, frequently, solution-characterization techniques cannot be used. Here we report solution gradients, prepared by electrochemical means, for controlling and monitoring reactivity at surfaces in space and time. As a proof of principle, electrochemically derived gradients of a reaction parameter (pH) and of a catalyst (Cu(I)) have been employed to make surface gradients on the micron scale and to study the kinetics of the (surface-confined) imine hydrolysis and the copper(I)-catalysed azide-alkyne 1,3-dipolar cycloaddition, respectively. For both systems, the kinetic data were spatially visualized in a two-dimensional reactivity map. In the case of the copper(I)-catalysed azide-alkyne 1,3-dipolar cycloaddition, the reaction order (2) was deduced from it.

  5. Toddlers Default to Canonical Surface-to-Meaning Mapping When Learning Verbs

    PubMed Central

    Dautriche, Isabelle; Cristia, Alejandrina; Brusini, Perrine; Yuan, Sylvia; Fisher, Cynthia; Christophe, Anne

    2013-01-01

    Previous work has shown that toddlers readily encode each noun in the sentence as a distinct argument of the verb. However, languages allow multiple mappings between form and meaning which do not fit this canonical format. Two experiments examined French 28-month-olds’ interpretation of right-dislocated sentences (nouni-verb, nouni) where the presence of clear, language-specific cues should block such a canonical mapping. Toddlers (N = 96) interpreted novel verbs embedded in these sentences as transitive, disregarding prosodic cues to dislocation (Experiment 1) but correctly interpreted right-dislocated sentences containing well-known verbs (Experiment 2). These results suggest that toddlers can integrate multiple cues in ideal conditions, but default to canonical surface-to-meaning mapping when extracting structural information about novel verbs in semantically impoverished conditions. PMID:24117408

  6. Real-Space Mapping of Surface Trap States in CIGSe Nanocrystals Using 4D Electron Microscopy.

    PubMed

    Bose, Riya; Bera, Ashok; Parida, Manas R; Adhikari, Aniruddha; Shaheen, Basamat S; Alarousu, Erkki; Sun, Jingya; Wu, Tom; Bakr, Osman M; Mohammed, Omar F

    2016-07-13

    Surface trap states in copper indium gallium selenide semiconductor nanocrystals (NCs), which serve as undesirable channels for nonradiative carrier recombination, remain a great challenge impeding the development of solar and optoelectronics devices based on these NCs. In order to design efficient passivation techniques to minimize these trap states, a precise knowledge about the charge carrier dynamics on the NCs surface is essential. However, selective mapping of surface traps requires capabilities beyond the reach of conventional laser spectroscopy and static electron microscopy; it can only be accessed by using a one-of-a-kind, second-generation four-dimensional scanning ultrafast electron microscope (4D S-UEM) with subpicosecond temporal and nanometer spatial resolutions. Here, we precisely map the collective surface charge carrier dynamics of copper indium gallium selenide NCs as a function of the surface trap states before and after surface passivation in real space and time using S-UEM. The time-resolved snapshots clearly demonstrate that the density of the trap states is significantly reduced after zinc sulfide (ZnS) shelling. Furthermore, the removal of trap states and elongation of carrier lifetime are confirmed by the increased photocurrent of the self-biased photodetector fabricated using the shelled NCs.

  7. Prior-knowledge-based spectral mixture analysis for impervious surface mapping

    SciTech Connect

    Zhang, Jinshui; He, Chunyang; Zhou, Yuyu; Zhu, Shuang; Shuai, Guanyuan

    2014-01-03

    In this study, we developed a prior-knowledge-based spectral mixture analysis (PKSMA) to map impervious surfaces by using endmembers derived separately for high- and low-density urban regions. First, an urban area was categorized into high- and low-density urban areas, using a multi-step classification method. Next, in high-density urban areas that were assumed to have only vegetation and impervious surfaces (ISs), the Vegetation-Impervious model (V-I) was used in a spectral mixture analysis (SMA) with three endmembers: vegetation, high albedo, and low albedo. In low-density urban areas, the Vegetation-Impervious-Soil model (V-I-S) was used in an SMA analysis with four endmembers: high albedo, low albedo, soil, and vegetation. The fraction of IS with high and low albedo in each pixel was combined to produce the final IS map. The root mean-square error (RMSE) of the IS map produced using PKSMA was about 11.0%, compared to 14.52% using four-endmember SMA. Particularly in high-density urban areas, PKSMA (RMSE = 6.47%) showed better performance than four-endmember (15.91%). The results indicate that PKSMA can improve IS mapping compared to traditional SMA by using appropriately selected endmembers and is particularly strong in high-density urban areas.

  8. Mapping of the cumulative β-ray dose on the ground surface surrounding the Fukushima area

    PubMed Central

    Endo, Satoru; Kajimoto, Tsuyoshi; Tanaka, Kenichi; Nguyen, Thanh T.; Hayashi, Gohei; Imanaka, Tetsuji

    2015-01-01

    A large amount of the fission products released by the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident on 11 March 2011 was deposited in a wide area from Tohoku to northern Kanto. A map of the estimated cumulative β-ray dose (70 μm dose equivalent) on the soil surface for one year after the FDNPP accident has been prepared using previously reported calculation methods and the 2-km mesh survey data by MEXT. From this map of estimated dose, areas with a high cumulative β-ray dose on the soil surface for one year after the FDNPP accident were found to be located in the Akogi-Teshichiro to Akogi-Kunugidaira region in Namie Town, and in the southern Futaba Town to the northern Tomioka Town region. The highest estimated cumulative β-ray dose was 710 mSv for one year at Akogi-Teshichiro, Namie Town. PMID:26519736

  9. The identification of molecular surfaces' feature regions based on spherical mapping

    NASA Astrophysics Data System (ADS)

    Zhang, Meiling; Zhang, Jingqiao

    2017-02-01

    As possible active sites, the concave and convex feature regions of the molecule are the locations where the molecular docking will happen more possibly. Then how to search for those regions is valuable to study. In this paper, a new method is proposed for identifying concave and convex regions. Based on the established spherical mapping between molecular surfaces and its bounding-sphere surfaces, the concave and convex vertices of local areas can be determined according to the expansion distance defined by the spherical mapping. Then through mesh growing, a feature region can be firmed by a concave point or a convex point, also called center point, and its neighboring faces, whose normal vector has an angle in a specified range with the center point. After that, areas and volumes of feature regions are calculated. The experimental results indicate that the method can well identify the concave and convex characteristics of the molecule.

  10. Functional mapping of cell surface proteins with localized stimulation of single cells

    NASA Astrophysics Data System (ADS)

    Sun, Bingyun; Chiu, Daniel T.

    2003-11-01

    This paper describes the development of using individual micro and nano meter-sized vesicles as delivery vessels to functionally map the distribution of cell surface proteins at the level of single cells. The formation of different sizes of vesicles from tens of nanometers to a few micrometers in diameter that contain the desired molecules is addressed. An optical trap is used to manipulate the loaded vesicle to specific cell morphology of interest, and a pulsed UV laser is used to photo-release the stimuli onto the cell membrane. Carbachol activated cellular calcium flux, upon binding to muscarinic acetylcholine receptors, is studied by this method, and the potential of using this method for the functional mapping of localized proteins on the cell surface membrane is discussed.

  11. The use of TIMS for mapping different pahoehoe surfaces: Mauna Iki, Kilauea

    NASA Technical Reports Server (NTRS)

    Rowland, Scott K.

    1992-01-01

    S-type and p-type pahoehoe record different mechanisms and vigors of activity within an active flow field. There is some controversy about what these mechanisms are exactly, and this study was undertaken with the idea that an accurate map of the two surfaces within a pahoehoe flow field could be helpful in solving the problem. Thermal Infrared Multispectral Scanner (TIMS) allows discrimination between s-type and p-type pahoehoe, and this ability was used to map the two surface types on the Mauna Iki satellite shield (southwest rift zone, Kilauea Volcano). TIMS was previously used to discriminate a'a from pahoehoe as well as to determine relative age relationships of different flows. Although inter-flow variation was minor in the data published by these authors, a second goal presented is to understand such variations to better constrain intra-flow differences used for age dating.

  12. Computation of Transfer Maps from Surface Data with Applications to Wigglers

    NASA Astrophysics Data System (ADS)

    Mitchell, Chad; Dragt, Alex

    2006-04-01

    Simulations indicate that the dynamic aperture of the proposed ILC Damping Rings is dictated primarily by the nonlinear properties of their wiggler transfer maps. Wiggler transfer maps in turn depend sensitively on fringe-field and high-multipole effects. Therefore it is important to have a detailed and realistic model of the interior magnetic field, including knowledge of high spatial derivatives. Modeling of these derivatives is made difficult by the presence of numerical noise. We describe how such information can be extracted reliably from 3-dimensional field data on a grid as provided, for example, by various 3-dimensional finite element field codes (OPERA-3d) available from Vector Fields. The key ingredients are the use of surface data and the smoothing property of the inverse Laplacian operator. We describe the advantages of fitting on an elliptic cylindrical surface surrounding the beam.

  13. Potentiometric surface map of the Magothy aquifer in southern Maryland, September, 2003

    USGS Publications Warehouse

    Curtin, Stephen E.; Andreasen, David C.; Wheeler, Judith C.

    2005-01-01

    This report presents a map showing the potentiometric surface of the Magothy aquifer in the Magothy Formation of Upper Cretaceous age in Southern Maryland during September 2002. The map is based on water-level measurements in 79 wells. The highest measured water level was 83 feet above sea level near the northern boundary and outcrop area of the aquifer in the north-central part of Anne Arundel County. The potentiometric surface declined towards the south and east. Local gradients were directed toward the centers of two cones of depression that developed in response to pumping. These cones of depression were centered around well fields in the Waldorf area and at the Chalk Point power plant. Measured ground-water levels were as low as 81 feet below sea level in the Waldorf area and 75 feet below sea level at Chalk Point.

  14. Mapping surface energy balance components by combining Landsat Thematic Mapper and ground-based meteorological data

    NASA Technical Reports Server (NTRS)

    Moran, M. Susan; Jackson, Ray D.; Raymond, Lee H.; Gay, Lloyd W.; Slater, Philip N.

    1989-01-01

    Surface energy balance components were evaluated by combining satellite-based spectral data with on-site measurements of solar irradiance, air temperature, wind speed, and vapor pressure. Maps of latent heat flux density and net radiant flux density were produced using Landsat TM data for three dates. The TM-based estimates differed from Bowen-ratio and aircraft-based estimates by less than 12 percent over mature fields of cotton, wheat, and alfalfa.

  15. VEM on VERITAS - Retrieval of global infrared surface emissivity maps of Venus and expectable retrieval uncertainties

    NASA Astrophysics Data System (ADS)

    Kappel, David; Arnold, Gabriele; Haus, Rainer; Helbert, Jörn; Smrekar, Suzanne; Hensley, Scott

    2016-04-01

    Even though Venus is in many respects the most Earth-like planet we know today, its surface composition and geology are not well understood yet. The major obstacle is the extremely dense, hot, and opaque atmosphere that complicates both in situ measurements and infrared remote sensing, the wavelength range of the latter often being the range of choice due to its coverage of many spectral properties diagnostic to the surface material's composition and texture. Thermal emissions of the hot surface depend on surface temperature and on spectral surface emissivity. As this emitted radiation wells upward, it is strongly attenuated through absorption and multiple scattering by the gaseous and particulate components of the dense atmosphere, and it is superimposed by thermal atmospheric emissions. While surface information this way carried to space is completely lost in the scattered sunlight on the dayside, a few narrow atmospheric transparency windows around 1 μm allow the sounding of the surface with nightside measurements. The successfully completed VEX ('Venus Express') mission, although not dedicated to surface science, enabled a first glimpse at much of the southern hemisphere's surface through the nightside spectral transparency windows covered by VIRTIS-M-IR ('Visible and InfraRed Thermal Imaging Spectrometer, Mapping channel in the IR', 1.0-5.1 μm). Two complementary approaches, a fast semi-empiric technique on the one hand, and a more fundamental but resource-intensive method based on a fully regularized Bayesian multi-spectrum retrieval algorithm in combination with a detailed radiative transfer simulation program on the other hand, were both successfully applied to derive surface emissivity data maps. Both methods suffered from lack of spatial coverage and a small SNR as well as from surface topography maps not sufficiently accurate for the definition of suitable boundary conditions for surface emissivity retrieval. The recently proposed VERITAS mission

  16. Metal-surface mapping by means of soft-x-ray laser interferometry

    NASA Astrophysics Data System (ADS)

    Albert, F.; Zeitoun, Ph.; Jaeglé, P.; Joyeux, D.; Boussoukaya, M.; Carillon, A.; Hubert, S.; Jamelot, G.; Klisnick, A.; Phalippou, D.; Ros, D.; Zeitoun-Fakiris, A.

    1999-10-01

    We present an investigation of perturbed surface states performed by using an X-UV laser (λ=21.2 nm). A dc electric field, which takes increasing values from 0 to 37 MV/m, is continuously applied to the surface of a niobium sample. The surface is irradiated by the pulsed 21.2-nanometer radiation of the X-UV laser, without breaking off the E field. A Fresnel bimirror interferometer supplies surface interferograms, which show the emergence of growing perturbations for an E field about 14 MV/m, even though no electric microbreakdown has yet been recorded between the anode and the Nb sample. The perturbed surface has been observed in a 0.3×9-nm area during hours, before and after an only electric breakdown which occurred at 37 MV/m. Surface maps, obtained by holographic reconstruction from interferograms, show local ``vertical'' surface shifts of 10-19 nm, which are more or less aligned on constant E-field lines. Comparison with ``post-mortem'' surface photographs obtained by the standard scanning electron microscopy method shows perturbation traces only in the small electric breakdown zone, which suggests the extreme-surface structure observed by X-UV laser interferometry to slowly vanish after the end of E-field application.

  17. Salts on Europa's surface detected by Galileo's near infrared mapping spectrometer

    USGS Publications Warehouse

    McCord, T.B.; Hansen, G.B.; Fanale, F.P.; Carlson, R.W.; Matson, D.L.; Johnson, T.V.; Smythe, W.D.; Crowley, J.K.; Martin, P.D.; Ocampo, A.; Hibbitts, C.A.; Granahan, J.C.

    1998-01-01

    Reflectance spectra in the 1- to 2.5-micrometer wavelength region of the surface of Europa obtained by Galileo's Near Infrared Mapping Spectrometer exhibit distorted water absorption bands that indicate the presence of hydrated minerals. The laboratory spectra of hydrated salt minerals such as magnesium sulfates and sodium carbonates and mixtures of these minerals provide a close match to the Europa spectra. The distorted bands are only observed in the optically darker areas of Europa, including the lineaments, and may represent evaporite deposits formed by water, rich in dissolved salts, reaching the surface from a water-rich layer underlying an ice crust.

  18. Three-dimensional surface deformation mapping by convensional interferometry and multiple aperture interferometry

    USGS Publications Warehouse

    Jung, H.-S.; Lu, Zhiming; Lee, C.-W.

    2011-01-01

    Interferometric synthetic aperture radar (InSAR) technique has been successfully used for mapping surface deformations [1-2], but it has been normally limited to a measurement along the radar line-of-sight (LOS) direction. For this reason, it is impossible to determine the north (N-S) component of surface deformation because of using data from near-polar orbiting satellites, and it is not sufficient to resolve the parameters of models for earthquakes and volcanic activities because there is a marked trade-off among model parameters [3]. ?? 2011 KIEES.

  19. Surface element-mapping of three dimensional structures by laser-induced breakdown spectroscopy

    NASA Astrophysics Data System (ADS)

    Beresko, Christian; Kohns, Peter; Ankerhold, Georg

    2014-09-01

    During lateral mapping with laser-induced breakdown spectroscopy (LIBS) the focal position of the plasma-generating laser needs to be kept stable on the sample surface area to be probed. Therefore, three-dimensional structures like edged surfaces require a permanent re-focusing. We describe a new auto-focusing technique to perform surface elemental mapping with LIBS by correcting the focusing lens-to-sample distance using a direct monitoring of the LIBS signal intensity. This method allows the scanning of surfaces with strong height fluctuations of several millimeters without the need of any additional devices. The auto-focusing method is valuable for LIBS applications made on complex-shaped samples or simply to improve the measurement reproducibility. Applications are LIBS analyses of samples exhibiting drill holes or steep edges. Our procedure does not need a constant focal plane and follows the topographic profile of the sample surface. Impurities and material inclusions are well detected. From the topographic information additionally obtained, a three-dimensional image of the sample can be deduced. Depth resolution is limited by the Rayleigh range of the LIBS laser light. The method is best suited for low energy laser pulses with high repetition rate and infrared emission.

  20. Generation of 3-D surface maps in waste storage silos using a structured light source

    NASA Technical Reports Server (NTRS)

    Burks, B. L.; Rowe, J. C.; Dinkins, M. A.; Christensen, B.; Selleck, C.; Jacoboski, D.; Markus, R.

    1992-01-01

    Surface contours inside the large waste storage tanks typical of the Department of Energy (DOE) complex are, in general, highly irregular. In addition to pipes and other pieces of equipment in the tanks, the surfaces may have features such as mounds, fissures, crystalline structures, and mixed solid and liquid forms. Prior to remediation activities, it will be necessary to characterize the waste to determine the most effective remediation approaches. Surface contour data will be required both prior to and during remediation. The use is described of a structured light source to generate 3-D surface contour maps of the interior of waste storage silos at the Feed Materials Production Center at Fernald, OH. The landscape inside these large waste storage tanks bears a strong resemblance to some of the landscapes that might be encountered during lunar or planetary exploration. Hence, these terrestrial 3-D mapping techniques may be directly applicable to extraterrestrial exploration. In further development, it will be demonstrated that these 3-D data can be used for robotic task planning just as 3-D surface contour data of a satellite could be used to plan maintenance tasks for a space-based servicing robot.

  1. Mapping land surface energy budget from the AVIRIS and MASTER data

    NASA Astrophysics Data System (ADS)

    Liang, S.; Wang, D.

    2015-12-01

    Mapping land surface energy budget from the AVIRIS and MASTER dataDongdong Wang, Shunlin Liang, Tao He, Qinqing ShiDepartment of Geographical SciencesUniversity of Maryland, College Park, MD 20742The synergy of the AVIRIS and MASTER data with high spatial and spectral resolutions provides us an unprecedented data resource to study the spatial variability of the land-atmosphere exchange of water, carbon and energy at the ecosystem scale. Supported by the NASA HyspIRI program, we have worked on developing algorithms to estimate quantities of surface energy and radiation budget from AVIRIS and MASTER data collected by the HyspIRI preparatory airborne campaign. We will here present results of algorithm development and data analysis, including 1) retrieving broadband surface albedo from AVIRIS, 2) estimating surface shortwave net radiation from hyperspectral data, 3) combing VSWIR and TIR data to estimate all-wave net radiation, and 4) mapping evapotranspiration from MASTER and ancillary data. Validation against field measurements and other satellite data suggests that surface albedo, shortwave net radiation, all-wave net radiation and ET can be estimated with improved resolution and accuracy from the AVIRIS and MASTER data.

  2. Developing Land Surface Type Map with Biome Classification Scheme Using Suomi NPP/JPSS VIIRS Data

    NASA Astrophysics Data System (ADS)

    Zhang, Rui; Huang, Chengquan; Zhan, Xiwu; Jin, Huiran

    2016-08-01

    Accurate representation of actual terrestrial surface types at regional to global scales is an important element for a wide range of applications, such as land surface parameterization, modeling of biogeochemical cycles, and carbon cycle studies. In this study, in order to meet the requirement of the retrieval of global leaf area index (LAI) and fraction of photosynthetically active radiation absorbed by the vegetation (fPAR) and other studies, a global map generated from Suomi National Polar- orbiting Partnership (S-NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) surface reflectance data in six major biome classes based on their canopy structures, which include: Grass/Cereal Crops, Shrubs, Broadleaf Crops, Savannas, Broadleaf Forests, and Needleleaf Forests, was created. The primary biome classes were converted from an International Geosphere-Biosphere Program (IGBP) legend global surface type data that was created in previous study, and the separation of two crop types are based on a secondary classification.

  3. High-Speed Laser Scanner Maps a Surface in Three Dimensions

    NASA Technical Reports Server (NTRS)

    Lavelle, Joseph; Schuet, Stefan

    2006-01-01

    A scanning optoelectronic instrument generates the digital equivalent of a threedimensional (X,Y,Z) map of a surface that spans an area with resolution on the order of 0.005 in. ( 0.125mm). Originally intended for characterizing surface flaws (e.g., pits) on space-shuttle thermal-insulation tiles, the instrument could just as well be used for similar purposes in other settings in which there are requirements to inspect the surfaces of many objects. While many commercial instruments can perform this surface-inspection function, the present instrument offers a unique combination of capabilities not available in commercial instruments. This instrument utilizes a laser triangulation method that has been described previously in NASA Tech Briefs in connection with simpler related instruments used for different purposes. The instrument includes a sensor head comprising a monochrome electronic camera and two lasers. The camera is a high-resolution

  4. A simple thermal model of the earth's surface for geologic mapping by remote sensing

    NASA Technical Reports Server (NTRS)

    Kahle, A. B.

    1977-01-01

    Thermal inertia of the earth's surface can be used in geologic mapping as a complement to surface reflectance data as provided by Landsat. Thermal inertia cannot be determined directly but must be inferred from radiation temperature measurements (by thermal IR sensors) made at various times in the diurnal cycle, combined with a model of the surface heating processes. A model is developed which differs from those created previously for this purpose, because it includes sensible and latent heating. Tests of this model using field data indicate that it accurately determines the surface heating. When the model is used with field measurements of meteorological variables and is combined with remotely sensed temperature data, a thermal inertia image can be produced.

  5. Mapping of Surface and Shallow Subsurface Signatures in the CONSERT Data during the Descent of Philae

    NASA Astrophysics Data System (ADS)

    Plettemeier, Dirk; Statz, Christoph; Hahnel, Ronny; Hegler, Sebastian; Kofman, Wlodek; Herique, Alain; Rogez, Yves; Pasquero, Pierre; Zine, Sonia; Ciarletti, Valerie

    2016-04-01

    The primary scientific objective of the Comet Nucleus Sounding Experiment by Radiowave Transmission (CONSERT) aboard Rosetta is the characterization of comet 67P/Chuyurmov-Gerasimenko's deep interior dielectric properties. This was done during the first science sequence (FSS) by means of bi-static radio propagation measurements between the the CONSERT instrument aboard lander Philae launched onto the comet's surface and its counterpart aboard the Rosetta orbiter. In addition to the FSS measurements, CONSERT was operated during the separation and descent of Philae onto the 67P/C-G's surface. The received CONSERT signal during the SDL consists of the direct propagation between Rosetta and Philae and indirect reflections of 67P/C-G's surface. Using the peak power measurements in the dominant direct path between Rosetta and Philae during the descent we were able to reconstruct the lander's attitude and estimate the spin rate of the lander along its descent trajectory. The deployment of the lander legs and CONSERT antennas as well as the orbiter change of attitude in order to orient the science towards the assumed lander position are visible in the measured CONSERT data as well. The information gained on Philae's attitude is used in the estimation of 67P/C-G's surface and near subsurface dielectric properties. Information on the surface of 67P/C-G are contained in the data during roughly the last third of the descent of Philae onto the comet's surface. The surface signatures in the measured data are mapped to the location of origin on 67P/C-G's surface. The results from the mapping process show good spatial diversity along the descent track of Philae necessary for the estimation of the dielectric properties of prominent features in the CONSERT SDL data.

  6. Compositional maps of 67P/CG nucleus surface after perihelion passage by Rosetta/VIRTIS

    NASA Astrophysics Data System (ADS)

    Filacchione, Gianrico; Ciarniello, M.; Capaccioni, F.; Raponi, A.; De Sanctis, M. C.; Tosi, F.; Migliorini, Alessandra; Piccioni, G.; Cerroni, P.; Capria, M. T.; Erard, S.; Bockelee-Morvan, D.; Leyrat, C.; Arnold, G.; Barucci, M. A.; Schmitt, B.; Quirico, E.

    2016-11-01

    Moving after perihelion passage (August 13th 2015), VIRTIS-M the 0.25-5.0 μm imaging spectrometer on board Rosetta has mapped again the north and equatorial regions of 67P/CG's nucleus with the scope to trace color and composition evolution of the surface. With the loss of the IR channel due to the active cryogenic cooler failure occurred in May 2015, VIRTIS-M has observed only with the VIS channel in the 0.25-1.0 μm spectral range. Despite this limitation, the returned data are valuable in performing a comparison of surface properties between pre and post-perihelion times. Approaching perihelion passage, 67P/CG's nucleus has experienced a general brightening due to the removal of the surficial dust layer caused by the more intense gaseous activity with the consequent exposure of a larger fraction of water ice. Coma observations by VIRTIS during pre-perihelion have shown a correlation between the areas of the nucleus where gaseous activity by water ice sublimation is more intense with the surface brightening caused by dust removal. After having applied data calibration and photometric correction, VIRTIS data are projected on the irregularly shaped digital model6 of 67P/CG with the aim to derive visible albedo and colors maps rendered with a spatial resolution of 0.5×0.5 deg in latitude-longitude, corresponding to a sampling of about 15 m/pixel. Dedicated mapping sequences executed at different heliocentric distances, are employed to follow the dynamical evolution of the surface. Direct comparison between compositional maps obtained at the same heliocentric distances along inbound and outbound orbits allows to evidence the changes occurred on the same areas of the surface. In this context, the first VIRTIS-M maps, obtained in August 2014 at heliocentric distance of 3.4 AU along the inbound orbit with a solar phase angle of about 30-45° are compared with the last ones, taken in June 2016 at 3.2 AU from the Sun on the outbound trajectory at solar phases of about

  7. Texture descriptions of lunar surface derived from LOLA data: Kilometer-scale roughness and entropy maps

    NASA Astrophysics Data System (ADS)

    Li, Bo; Ling, Zongcheng; Zhang, Jiang; Chen, Jian; Wu, Zhongchen; Ni, Yuheng; Zhao, Haowei

    2015-11-01

    The lunar global texture maps of roughness and entropy are derived at kilometer scales from Digital Elevation Models (DEMs) data obtained by Lunar Orbiter Laser Altimeter (LOLA) aboard on Lunar Reconnaissance Orbiter (LRO) spacecraft. We use statistical moments of a gray-level histogram of elevations in a neighborhood to compute the roughness and entropy value. Our texture descriptors measurements are shown in global maps at multi-sized square neighborhoods, whose length of side is 3, 5, 10, 20, 40 and 80 pixels, respectively. We found that large-scale topographical changes can only be displayed in maps with longer side of neighborhood, but the small scale global texture maps are more disorderly and unsystematic because of more complicated textures' details. Then, the frequency curves of texture maps are made out, whose shapes and distributions are changing as the spatial scales increases. Entropy frequency curve with minimum 3-pixel scale has large fluctuations and six peaks. According to this entropy curve we can classify lunar surface into maria, highlands, different parts of craters preliminarily. The most obvious textures in the middle-scale roughness and entropy maps are the two typical morphological units, smooth maria and rough highlands. For the impact crater, its roughness and entropy value are characterized by a multiple-ring structure obviously, and its different parts have different texture results. In the last, we made a 2D scatter plot between the two texture results of typical lunar maria and highlands. There are two clusters with largest dot density which are corresponded to the lunar highlands and maria separately. In the lunar mare regions (cluster A), there is a high correlation between roughness and entropy, but in the highlands (Cluster B), the entropy shows little change. This could be subjected to different geological processes of maria and highlands forming different landforms.

  8. A Near-Infrared and Thermal Imager for Mapping Titan's Surface Features

    NASA Technical Reports Server (NTRS)

    Aslam, S.; Hewagma, T.; Jennings, D. E.; Nixon, C.

    2012-01-01

    Approximately 10% of the solar insolation reaches the surface of Titan through atmospheric spectral windows. We will discuss a filter based imaging system for a future Titan orbiter that will exploit these windows mapping surface features, cloud regions, polar storms. In the near-infrared (NIR), two filters (1.28 micrometer and 1.6 micrometer), strategically positioned between CH1 absorption bands, and InSb linear array pixels will explore the solar reflected radiation. We propose to map the mid, infrared (MIR) region with two filters: 9.76 micrometer and 5.88-to-6.06 micrometers with MCT linear arrays. The first will map MIR thermal emission variations due to surface albedo differences in the atmospheric window between gas phase CH3D and C2H4 opacity sources. The latter spans the crossover spectral region where observed radiation transitions from being dominated by thermal emission to solar reflected light component. The passively cooled linear arrays will be incorporated into the focal plane of a light-weight thin film stretched membrane 10 cm telescope. A rad-hard ASIC together with an FPGA will be used for detector pixel readout and detector linear array selection depending on if the field-of-view (FOV) is looking at the day- or night-side of Titan. The instantaneous FOV corresponds to 3.1, 15.6, and 31.2 mrad for the 1, 5, and 10 micrometer channels, respectively. For a 1500 km orbit, a 5 micrometer channel pixel represents a spatial resolution of 91 m, with a FOV that spans 23 kilometers, and Titan is mapped in a push-broom manner as determined by the orbital path. The system mass and power requirements are estimated to be 6 kg and 5 W, respectively. The package is proposed for a polar orbiter with a lifetime matching two Saturn seasons.

  9. Surface magnetic field mapping on high albedo marking areas of the moon

    NASA Astrophysics Data System (ADS)

    Shibuya, H.; Aikawa, K.; Tsunakawa, H.; Takahashi, F.; Shimizu, H.; Matsushima, M.

    2009-12-01

    The correlation between high albedo markings (HAM) on the surface of the moon and strong magnetic anomalies has been claimed since the early time of the lunar magnetic field study (Hood and Schubert, 1980). Hood et al. (1989) mapped the smoothed magnetic field over the Reiner Gamma region using Lunar Prospector magnetometer (LP-MAG) data, and showed that the position of them matches well. We have developed a method to recover the 3-d magnetic field from satellite field observations (EPR method which stands for Equivalent Pole Reduction; Toyoshima et al. 2008). Applying EPR to the several areas of strong magnetic anomalies, we calculated the magnetic anomaly maps of near surface regions, to see how the anomaly and the HAM correlate each other. The data used is of the Lunar Prospector magnetometer (LP-MAG). They are selected from low altitude observations performed in 1998 to 1999. The areas studied are Reiner Gamma, Airy, Descartes, Abel, and Crisium Antipode regions. The EPR determines a set of magnetic monopoles at the moon surface which produce the magnetic field of the observation. In each studied area, we put poles in 0.1° intervals of both latitude and longitude, then the magnetic field at 5km in altitude is calculated. The field distribution is superimposed with the albedo map made from Clementine data. The total force (Bf) maps indicate that the HMA occurs at the strong anomaly regions, but their shape does not quite overlie. However, taking horizontal component (Bh), not only position but the shape and size of the anomalies coincide with HMA regions. It is particularly true for the Reiner Gamma, and Descartes regions. The shape of HMA fits in a Bh contour. The HMA is argued to be formed by the reduction of solar wind particles which are shielded by the magnetic field. Since the deflection of the charged particle becomes large at large horizontal component, the Bh distribution showed here support the argument.

  10. A framework to analyze cerebral mean diffusivity using surface guided diffusion mapping in diffusion tensor imaging

    PubMed Central

    Kwon, Oh-Hun; Park, Hyunjin; Seo, Sang-Won; Na, Duk L.; Lee, Jong-Min

    2015-01-01

    The mean diffusivity (MD) value has been used to describe microstructural properties in Diffusion Tensor Imaging (DTI) in cortical gray matter (GM). Recently, researchers have applied a cortical surface generated from the T1-weighted volume. When the DTI data are analyzed using the cortical surface, it is important to assign an accurate MD value from the volume space to the vertex of the cortical surface, considering the anatomical correspondence between the DTI and the T1-weighted image. Previous studies usually sampled the MD value using the nearest-neighbor (NN) method or Linear method, even though there are geometric distortions in diffusion-weighted volumes. Here we introduce a Surface Guided Diffusion Mapping (SGDM) method to compensate for such geometric distortions. We compared our SGDM method with results using NN and Linear methods by investigating differences in the sampled MD value. We also projected the tissue classification results of non-diffusion-weighted volumes to the cortical midsurface. The CSF probability values provided by the SGDM method were lower than those produced by the NN and Linear methods. The MD values provided by the NN and Linear methods were significantly greater than those of the SGDM method in regions suffering from geometric distortion. These results indicate that the NN and Linear methods assigned the MD value in the CSF region to the cortical midsurface (GM region). Our results suggest that the SGDM method is an effective way to correct such mapping errors. PMID:26236180

  11. First measurements of error fields on W7-X using flux surface mapping

    DOE PAGES

    Lazerson, Samuel A.; Otte, Matthias; Bozhenkov, Sergey; ...

    2016-08-03

    Error fields have been detected and quantified using the flux surface mapping diagnostic system on Wendelstein 7-X (W7-X). A low-field 'more » $${\\rlap{-}\\ \\iota} =1/2$$ ' magnetic configuration ($${\\rlap{-}\\ \\iota} =\\iota /2\\pi $$ ), sensitive to error fields, was developed in order to detect their presence using the flux surface mapping diagnostic. In this configuration, a vacuum flux surface with rotational transform of n/m = 1/2 is created at the mid-radius of the vacuum flux surfaces. If no error fields are present a vanishingly small n/m = 5/10 island chain should be present. Modeling indicates that if an n = 1 perturbing field is applied by the trim coils, a large n/m = 1/2 island chain will be opened. This island chain is used to create a perturbation large enough to be imaged by the diagnostic. Phase and amplitude scans of the applied field allow the measurement of a small $$\\sim 0.04$$ m intrinsic island chain with a $${{130}^{\\circ}}$$ phase relative to the first module of the W7-X experiment. Lastly, these error fields are determined to be small and easily correctable by the trim coil system.« less

  12. Map showing the potentiometric surface of the Magothy Aquifer in southern Maryland, September 1982

    USGS Publications Warehouse

    Mack, Frederick K.; Wheeler, Judith C.; Curtin, Stephen E.

    1982-01-01

    A map was prepared that shows the potentiometric surface of the Magothy aquifer in southern Maryland in September 1982. The map is based on measurements from a network of 83 observation wells. The highest levels of the potentiometric surface, 57 and 58 feet above sea level, were measured near the outcrop-subcrop of the aquifer in topographically high areas of Anne Arundel and Prince Georges Counties. The potentiometric surface slopes to the southeast to about sea level along much of the western shore of the Chesapeake Bay. Three distinct and extensive cones of depression have developed in the potentiometric surface around the well fields of the Annapolis area, Waldorf area, and Chalk Point. Several square miles of each cone are below sea level, and in some areas at Chalk Point and Waldorf, the cone is more than 50 feet below sea level. The network of wells was developed as part of the cooperative program between the U.S. Geological Survey, the Maryland Geological Survey, and the Maryland Energy Administration. (USGS)

  13. First measurements of error fields on W7-X using flux surface mapping

    SciTech Connect

    Lazerson, Samuel A.; Otte, Matthias; Bozhenkov, Sergey; Biedermann, Christoph; Pedersen, Thomas Sunn

    2016-08-03

    Error fields have been detected and quantified using the flux surface mapping diagnostic system on Wendelstein 7-X (W7-X). A low-field '${\\rlap{-}\\ \\iota} =1/2$ ' magnetic configuration (${\\rlap{-}\\ \\iota} =\\iota /2\\pi $ ), sensitive to error fields, was developed in order to detect their presence using the flux surface mapping diagnostic. In this configuration, a vacuum flux surface with rotational transform of n/m = 1/2 is created at the mid-radius of the vacuum flux surfaces. If no error fields are present a vanishingly small n/m = 5/10 island chain should be present. Modeling indicates that if an n = 1 perturbing field is applied by the trim coils, a large n/m = 1/2 island chain will be opened. This island chain is used to create a perturbation large enough to be imaged by the diagnostic. Phase and amplitude scans of the applied field allow the measurement of a small $\\sim 0.04$ m intrinsic island chain with a ${{130}^{\\circ}}$ phase relative to the first module of the W7-X experiment. Lastly, these error fields are determined to be small and easily correctable by the trim coil system.

  14. A LiDAR based analysis of hydraulic hazard mapping

    NASA Astrophysics Data System (ADS)

    Cazorzi, F.; De Luca, A.; Checchinato, A.; Segna, F.; Dalla Fontana, G.

    2012-04-01

    Mapping hydraulic hazard is a ticklish procedure as it involves technical and socio-economic aspects. On the one hand no dangerous areas should be excluded, on the other hand it is important not to exceed, beyond the necessary, with the surface assigned to some use limitations. The availability of a high resolution topographic survey allows nowadays to face this task with innovative procedures, both in the planning (mapping) and in the map validation phases. The latter is the object of the present work. It should be stressed that the described procedure is proposed purely as a preliminary analysis based on topography only, and therefore does not intend in any way to replace more sophisticated analysis methods requiring based on hydraulic modelling. The reference elevation model is a combination of the digital terrain model and the digital building model (DTM+DBM). The option of using the standard surface model (DSM) is not viable, as the DSM represents the vegetation canopy as a solid volume. This has the consequence of unrealistically considering the vegetation as a geometric obstacle to water flow. In some cases the topographic model construction requires the identification and digitization of the principal breaklines, such as river banks, ditches and similar natural or artificial structures. The geometrical and topological procedure for the validation of the hydraulic hazard maps is made of two steps. In the first step the whole area is subdivided into fluvial segments, with length chosen as a reasonable trade-off between the need to keep the hydrographical unit as complete as possible, and the need to separate sections of the river bed with significantly different morphology. Each of these segments is made of a single elongated polygon, whose shape can be quite complex, especially for meandering river sections, where the flow direction (i.e. the potential energy gradient associated to the talweg) is often inverted. In the second step the segments are analysed

  15. Accuracy Analysis of a Robotic Radionuclide Inspection and Mapping System for Surface Contamination

    SciTech Connect

    Mauer, Georg F.; Kawa, Chris

    2008-01-15

    The mapping of localized regions of radionuclide contamination in a building can be a time consuming and costly task. Humans moving hand-held radiation detectors over the target areas are subject to fatigue. A contamination map based on manual surveys can contain significant operator-induced inaccuracies. A Fanuc M16i light industrial robot has been configured for installation on a mobile aerial work platform, such as a tall forklift. When positioned in front of a wall or floor surface, the robot can map the radiation levels over a surface area of up to 3 m by 3 m. The robot's end effector is a commercial alpha-beta radiation sensor, augmented with range and collision avoidance sensors to ensure operational safety as well as to maintain a constant gap between surface and radiation sensors. The accuracy and repeatability of the robotically conducted contamination surveys is directly influenced by the sensors and other hardware employed. This paper presents an in-depth analysis of various non-contact sensors for gap measurement, and the means to compensate for predicted systematic errors that arise during the area survey scans. The range sensor should maintain a constant gap between the radiation counter and the surface being inspected. The inspection robot scans the wall surface horizontally, moving down at predefined vertical intervals after each scan in a meandering pattern. A number of non-contact range sensors can be employed for the measurement of the gap between the robot end effector and the wall. The nominal gap width was specified as 10 mm, with variations during a single scan not to exceed {+-} 2 mm. Unfinished masonry or concrete walls typically exhibit irregularities, such as holes, gaps, or indentations in mortar joints. These irregularities can be sufficiently large to indicate a change of the wall contour. The responses of different sensor types to the wall irregularities vary, depending on their underlying principles of operation. We explored

  16. A wafer mapping technique for residual stress in surface micromachined films

    NASA Astrophysics Data System (ADS)

    Schiavone, G.; Murray, J.; Smith, S.; Desmulliez, M. P. Y.; Mount, A. R.; Walton, A. J.

    2016-09-01

    The design of MEMS devices employing movable structures is crucially dependant on the mechanical behaviour of the deposited materials. It is therefore important to be able to fully characterize the micromachined films and predict with confidence the mechanical properties of patterned structures. This paper presents a characterization technique that enables the residual stress in MEMS films to be mapped at the wafer level by using microstructures released by surface micromachining. These dedicated MEMS test structures and the associated measurement techniques are used to extract localized information on the strain and Young’s modulus of the film under investigation. The residual stress is then determined by numerically coupling this data with a finite element analysis of the structure. This paper illustrates the measurement routine and demonstrates it with a case study using electrochemically deposited alloys of nickel and iron, particularly prone to develop high levels of residual stress. The results show that the technique enables wafer mapping of film non-uniformities and identifies wafer-to-wafer differences. A comparison between the results obtained from the mapping technique and conventional wafer bow measurements highlights the benefits of using a procedure tailored to films that are non-uniform, patterned and surface-micromachined, as opposed to simple standard stress extraction methods. The presented technique reveals detailed information that is generally unexplored when using conventional stress extraction methods such as wafer bow measurements.

  17. Mapping of Planetary Surface Age Based on Crater Statistics Obtained by AN Automatic Detection Algorithm

    NASA Astrophysics Data System (ADS)

    Salih, A. L.; Mühlbauer, M.; Grumpe, A.; Pasckert, J. H.; Wöhler, C.; Hiesinger, H.

    2016-06-01

    The analysis of the impact crater size-frequency distribution (CSFD) is a well-established approach to the determination of the age of planetary surfaces. Classically, estimation of the CSFD is achieved by manual crater counting and size determination in spacecraft images, which, however, becomes very time-consuming for large surface areas and/or high image resolution. With increasing availability of high-resolution (nearly) global image mosaics of planetary surfaces, a variety of automated methods for the detection of craters based on image data and/or topographic data have been developed. In this contribution a template-based crater detection algorithm is used which analyses image data acquired under known illumination conditions. Its results are used to establish the CSFD for the examined area, which is then used to estimate the absolute model age of the surface. The detection threshold of the automatic crater detection algorithm is calibrated based on a region with available manually determined CSFD such that the age inferred from the manual crater counts corresponds to the age inferred from the automatic crater detection results. With this detection threshold, the automatic crater detection algorithm can be applied to a much larger surface region around the calibration area. The proposed age estimation method is demonstrated for a Kaguya Terrain Camera image mosaic of 7.4 m per pixel resolution of the floor region of the lunar crater Tsiolkovsky, which consists of dark and flat mare basalt and has an area of nearly 10,000 km2. The region used for calibration, for which manual crater counts are available, has an area of 100 km2. In order to obtain a spatially resolved age map, CSFDs and surface ages are computed for overlapping quadratic regions of about 4.4 x 4.4 km2 size offset by a step width of 74 m. Our constructed surface age map of the floor of Tsiolkovsky shows age values of typically 3.2-3.3 Ga, while for small regions lower (down to 2.9 Ga) and higher

  18. SU-F-BRF-08: Conformal Mapping-Based 3D Surface Matching and Registration

    SciTech Connect

    Song, Y; Zeng, W; Gu, X; Liu, C

    2014-06-15

    Purpose: Recently, non-rigid 3D surface matching and registration has been used extensively in engineering and medicine. However, matching 3D surfaces undergoing non-rigid deformation accurately is still a challenging mathematical problem. In this study, we present a novel algorithm to address this issue by introducing intrinsic symmetry to the registration Methods: Our computational algorithm for symmetric conformal mapping is divided into three major steps: 1) Finding the symmetric plane; 2) Finding feature points; and 3) Performing cross registration. The key strategy is to preserve the symmetry during the conformal mapping, such that the image on the parameter domain is symmetric and the area distortion factor on the parameter image is also symmetric. Several novel algorithms were developed using different conformal geometric tools. One was based on solving Riemann-Cauchy equation and the other one employed curvature flow Results: Our algorithm was implemented using generic C++ on Windows XP and used conjugate gradient search optimization for acceleration. The human face 3D surface images were acquired using a high speed 3D scanner based on the phase-shifting method. The scanning speed was 30 frames/sec. The image resolution for each frame was 640 × 480. For 3D human face surfaces with different expressions, postures, and boundaries, our algorithms were able to produce consistent result on the texture pattern on the overlapping region Conclusion: We proposed a novel algorithm to improve the robustness of conformal geometric methods by incorporating the symmetric information into the mapping process. To objectively evaluate its performance, we compared it with most existing techniques. Experimental results indicated that our method outperformed all the others in terms of robustness. The technique has a great potential in real-time patient monitoring and tracking in image-guided radiation therapy.

  19. Sea-surface temperature and salinity mapping from remote microwave radiometric measurements of brightness temperature

    NASA Technical Reports Server (NTRS)

    Hans-Juergen, C. B.; Kendall, B. M.; Fedors, J. C.

    1977-01-01

    A technique to measure remotely sea surface temperature and salinity was demonstrated with a dual frequency microwave radiometer system. Accuracies in temperature of 1 C and in salinity of part thousand for salinity greater than 5 parts per thousand were attained after correcting for the influence of extraterrestrial background radiation, atmospheric radiation and attenuation, sea-surface roughness, and antenna beamwidth. The radiometers, operating at 1.43 and 2.65 GHz, comprise a third-generation system using null balancing and feedback noise injection. Flight measurements from an aircraft at an altitude of 1.4 km over the lower Chesapeake Bay and coastal areas of the Atlantic Ocean resulted in contour maps of sea-surface temperature and salinity with a spatial resolution of 0.5 km.

  20. Map showing the potentiometric surface of the Magothy Aquifer in southern Maryland, August 1980

    USGS Publications Warehouse

    Mack, Frederick K.; Wheeler, Judith C.; Curtin, Stephen E.

    1981-01-01

    This map is based on measurements made in a network of 77 observation wells. Highest levels of the potentiometric surface, 61 to 64 feet above sea level, were near the outcrop or subcrop of the aquifer in topographically high areas of Anne Arundel and northern Prince Georges Counties. The potentiometric surface slopes toward centers of pumpage near Annapolis, in northern Charles County, and southern Prince Georges County. Two separate , distinct, and extensive cones of depression have developed in the surface around the well fields of Waldorf, in northern Charles County, and the Chalk Point power plant, in southern Prince Georges County. The cone of depression in the Annapolis area has coalesced with a more shallow cone that includes the Broadneck Peninsula. The network of wells was developed and is operated and maintained as part of the cooperative program between the U.S. Geological Survey and agencies of the Maryland Department of Natural Resources. (USGS)

  1. Surface temperature variations as measured by the Heat Capacity Mapping Mission

    NASA Technical Reports Server (NTRS)

    Price, J. C.

    1979-01-01

    The AEM-1 satellite, the Heat Capacity Mapping Mission, has acquired high-quality thermal infrared data at times of day especially suited for studying the earth's surface and the exchange of heat and moisture with the atmosphere. Selected imagery illustrates the considerable variability of surface temperature in and around cities, in the dry southwestern United States, in the Appalachian Mountains, and in agricultural areas. Through simplifying assumptions, an analytic experience is derived that relates day/night temperature differences to the near-surface layer (thermal inertia) and to meteorological factors. Analysis of the result suggests that, in arid regions, estimates of relative thermal inertia may be inferred, whereas, in agricultural areas, a hydrologic interpretation is possible.

  2. Geostatistical investigations for suitable mapping of the water table: the Bordeaux case (France)

    NASA Astrophysics Data System (ADS)

    Guekie simo, Aubin Thibaut; Marache, Antoine; Lastennet, Roland; Breysse, Denys

    2016-02-01

    Methodologies have been developed to establish realistic water-table maps using geostatistical methods: ordinary kriging (OK), cokriging (CoK), collocated cokriging (CoCoK), and kriging with external drift (KED). In fact, in a hilly terrain, when piezometric data are sparsely distributed over large areas, the water-table maps obtained by these methods provide exact water levels at monitoring wells but fail to represent the groundwater flow system, manifested through an interpolated water table above the topography. A methodology is developed in order to rebuild water-table maps for urban areas at the city scale. The interpolation methodology is presented and applied in a case study where water levels are monitored at a set of 47 points for a part urban domain covering 25.6 km2 close to Bordeaux city, France. To select the best method, a geographic information system was used to visualize surfaces reconstructed with each method. A cross-validation was carried out to evaluate the predictive performances of each kriging method. KED proves to be the most accurate and yields a better description of the local fluctuations induced by the topography (natural occurrence of ridges and valleys).

  3. High Resolution Maps of the Moon Surface with AMIE/SMART-1

    NASA Astrophysics Data System (ADS)

    Despan, Daniela; Erard, S.; Barucci, A.; Josset, J. L.; Beauvivre, S.; Chevrel, S.; Pinet, P.; Koschny, D.; Almeida, M.; Grieger, B.; Foing, B.; AMIE Team

    2008-09-01

    The Advanced Moon micro-Imager Experiment (AMIE) on board the ESA lunar mission Smart-1 has performed colour imaging of the lunar surface using various filters in the visible and NIR range. This micro-camera provided high resolution images of selected parts of the lunar surface, including the North and South pole areas. Being give that the SMART-1 mission was in a 300km x 300km orbit with perilune over the South pole, the coverage between the North and the South regions is different. The AMIE images were obtained using a tele-objective with 5.3° x 5.3° field of view and a sensor of 1024 x 1024 pixels. The output images have resolution 45m/pixel at 500km, and are encoded with 10 bits/pixel. The data for the North pole were obtained at a much higher altitude than the South pole data. From the 300 Km pericenter altitude, the same field of view corresponds to a spatial resolution about 27 m/pixel. The high resolution imaging of the Moon surface makes possible detailed analysis of the morphological features and physical characteristics of the lunar surface. In order to construct AMIE data maps, systematic analysis and processing is being carried on using the whole data set. Geometrical analysis of AMIE images relies on the SPICE system: image coordinates are computed to get precise projection at the surface, and illumination angles are computed to analyze the photometric sequences. Using this method, high resolution mosaics were constructed then compared to lower resolution Clementine UV-Vis and NIR images. Maps of both North and South pole were obtained as well as other regions of interest. Eventually, this method will be applied in all areas where AMIE has provided high resolution observations of the surface, typically a factor of 3 higher than the Clementine UV-Vis camera. New results will be presented at the conference.

  4. MAPs/bFGF-PLGA microsphere composite-coated titanium surfaces promote increased adhesion and proliferation of fibroblasts.

    PubMed

    Wang, Zhongshan; Wu, Guofeng; Bai, Shizhu; Feng, Zhihong; Dong, Yan; Zhou, Jian; Qin, Haiyan; Zhao, Yimin

    2014-06-01

    Infection and epithelial downgrowth are two major problems with maxillofacial transcutaneous implants, and both are mainly due to lack of stable closure of soft tissues at transcutaneous sites. Fibroblasts have been shown to play a key role in the formation of biological seals. In this work, titanium (Ti) model surfaces were coated with mussel adhesive proteins (MAPs) utilizing its unique adhesion ability on diverse inorganic and organic surfaces in wet environments. Prepared basic fibroblast growth factor (bFGF)-poly(lactic-co-glycolic acid) (PLGA) microspheres can be easily synthesized and combined onto MAPs-coated Ti surfaces, due to the negative surface charges of microspheres in aqueous solution, which is in contrast to the positive charges of MAPs. Titanium model surfaces were divided into three groups. Group A: MAPs/bFGF-PLGA microspheres composite-coated Ti surfaces. Group B: MAPs-coated Ti surfaces. Group C: uncoated Ti surfaces. The effects of coated Ti surfaces on adhesion of fibroblasts, cytoskeletal organization, proliferation, and extracellular matrix (ECM)-related gene expressions were examined. The results revealed increased adhesion (P < 0.05), enhanced actin cytoskeletal organization, and up-regulated ECM-related gene expressions in groups A and B compared with group C. Increased proliferation of fibroblasts during five days of incubation was observed in group A compared with groups B and C (P < 0.05). Collectively, the results from this in vitro study demonstrated that MAPs/bFGF-PLGA microspheres composite-coated Ti surfaces had the ability to increase fibroblast functionality. In addition, MAPs/bFGF-PLGA microsphere composite-coated Ti surfaces should be studied further as a method of promoting formation of stable biological seals around transcutaneous sites.

  5. Extrinsic geometry of strings and the Gauss map of surfaces in R sup n

    SciTech Connect

    Parthasarathy, R.; Viswanathan, K.S. )

    1992-03-30

    This paper reports on a two-dimensional Euclidean string world sheet realized as a conformal immersion in R{sup n} which is mapped into the Grassmannian G{sub 2,n} through the generalized Gauss map. In order for the Grassmannian to represent tangent planes to a given surface, n {minus} 2 integrability conditions must be satisfied by the G{sub 2,n} fields. These conditions are explicitly derived for arbitrary n by realizing G{sub 2,n} as a quadric in CP{sup n{minus}1}. Both the intrinsic and the extrinsic geometrical properties of the string world sheet are expressed in terms of the Kahler {sigma} model fields.

  6. Retrieval Algorithms for Road Surface Modelling Using Laser-Based Mobile Mapping.

    PubMed

    Jaakkola, Anttoni; Hyyppä, Juha; Hyyppä, Hannu; Kukko, Antero

    2008-09-01

    Automated processing of the data provided by a laser-based mobile mapping system will be a necessity due to the huge amount of data produced. In the future, vehiclebased laser scanning, here called mobile mapping, should see considerable use for road environment modelling. Since the geometry of the scanning and point density is different from airborne laser scanning, new algorithms are needed for information extraction. In this paper, we propose automatic methods for classifying the road marking and kerbstone points and modelling the road surface as a triangulated irregular network. On the basis of experimental tests, the mean classification accuracies obtained using automatic method for lines, zebra crossings and kerbstones were 80.6%, 92.3% and 79.7%, respectively.

  7. Mapping the pollutants in surface riverine flood plume waters in the Great Barrier Reef, Australia.

    PubMed

    Devlin, M J; McKinna, L W; Alvarez-Romero, J G; Petus, C; Abott, B; Harkness, P; Brodie, J

    2012-01-01

    The extent of flood plume water over a 10 year period was mapped using quasi-true colour imagery and used to calculate long-term frequency of occurrence of the plumes. The proportional contribution of riverine loads of dissolved inorganic nitrogen, total suspended sediments and Photosystem-II herbicides from each catchment was used to scale the surface exposure maps for each pollutant. A classification procedure was also applied to satellite imagery (only Wet Tropics region) during 11 flood events (2000-2010) through processing of level-2 ocean colour products to discriminate the changing characteristics across three water types: "primary plume water", characterised by high TSS values; "secondary plume water", characterised by high phytoplankton production as measured by elevated chlorophyll-a (chl-a), and "tertiary plume water", characterised by elevated coloured dissolved and detrital matter (CDOM+D). This classification is a first step to characterise flood plumes.

  8. Expansion of polynomial Lie group integrals in terms of certain maps on surfaces, and factorizations of permutations

    NASA Astrophysics Data System (ADS)

    Novaes, Marcel

    2017-02-01

    Using the diagrammatic approach to integrals over Gaussian random matrices, we find a representation for polynomial Lie group integrals as infinite sums over certain maps on surfaces. The maps involved satisfy a specific condition: they have some marked vertices, and no closed walks that avoid these vertices. We also formulate our results in terms of permutations, arriving at new kinds of factorization problems.

  9. Global mapping of the surface of Titan through the haze with VIMS onboard Cassini

    NASA Astrophysics Data System (ADS)

    Le Mouélic, Stéphane; Cornet, Thomas; Rodriguez, Sébastien; Sotin, Christophe; Barnes, Jason W.; Brown, Robert H.; Lasue, Jérémie; Baines, K. H.; Buratti, Bonnie; Clark, Roger Nelson; Nicholson, Philip D.

    2016-10-01

    The Visual and Infrared Mapping Spectrometer (VIMS) onboard Cassini observes the surface of Titan through the atmosphere in seven narrow spectral windows in the infrared at 0.93, 1.08, 1.27, 1.59, 2.01, 2.68-2.78, and 4.9-5.1 microns. We have produced a global hyperspectral mosaic at 32 pixels per degrees of the complete VIMS data set of Titan between T0 (July 2004) and T120 (June 2016) flybys. We merged all the data cubes sorted by increasing spatial resolution, with the high resolution images on top of the mosaic and the low resolution images used as background. One of the main challenge in producing global spectral composition maps is to remove the seams between individual frames taken throughout the entire mission. These seams are mainly due to the widely varying viewing angles between data acquired during the different Titan flybys. These angles induce significant surface photometric effects and a strongly varying atmospheric (absorption and scattering) contribution, the scattering of the atmosphere being all the more present than the wavelength is short. We have implemented a series of empirical corrections to homogenize the maps, by correcting at first order for photometric and atmospheric scattering effects. Recently, the VIMS' IR wavelength calibration has been observed to be drifting from a total of a few nm toward longer wavelengths, the drift being almost continuously present over the course of the mission. Whereas minor at first order, this drift has implications on the homogeneity of the maps when trying to fit images taken at the beginning of the mission with images taken near the end, in particular when using channels in the narrowest atmospheric spectral windows. A correction scheme has been implemented to account for this subtle effect.

  10. Body-surface potential mapping to aid ablation of scar-related ventricular tachycardia.

    PubMed

    Sapp, John L; Gardner, Martin J; Parkash, Ratika; Basta, Magdy; Warren, James W; Horácek, B Milan

    2006-10-01

    We investigated whether body-surface potential mapping (BSPM) during catheter ablation of scar-related ventricular tachycardia (VT) could assist with the identification of VT exit sites. The study population consisted of 9 patients who underwent catheter ablation for VT, among whom 12 induced VTs with known exit sites were identified by entrainment criteria, pace mapping, or site of successful ablation. Paced activation was initiated at various intracardiac sites (20 +/- 4 sites per patient, a total of 180) documented by nonfluoroscopic electroanatomic mapping. During all episodes of VT and pacing, patients had a 120-lead electrocardiogram recorded, and we analyzed these electrocardiographic data--by means of a similarity coefficient (SC) calculated over 100 milliseconds after the initiation of depolarization--to assess the similarity between the BSPM sequences occurring during VTs and those induced by pacing. Based on 245 observations, the relationship between the SC and the distance of the pacing site from the VT exit site was then obtained for each individual VT by linear regression analysis: the distance D (in millimeters) from the VT exit site was related to SC by the regression equation D = slope (1 - SC2) + intercept. The parameters in this equation varied widely for the 12 VTs, but, in general, the nearer the pacing site was to the exit site, the better the goodness of match. This suggests that, although there is no universally applicable relationship between D and SC, BSPM could provide a useful adjunct to standard pace mapping, although additional processing--namely, an inverse calculation of epicardial potentials/isochrones--may be needed to reliably identify VT exit sites from body-surface electrocardiograms.

  11. Genus Oblivious Cross Parameterization: Robust Topological Management of Inter-surface Maps

    SciTech Connect

    Bennett, J C; Pascucci, V; Joy, K I

    2007-10-23

    We consider the problem of generating a map between two triangulated meshes, M and M{prime}, with arbitrary and possibly differing genus. This problem has rarely been tackled in its generality. Early schemes considered only topological spheres. Recent algorithms allow inputs with an arbitrary number of tunnels but require M and M{prime} to have equal genus, mapping tunnel to tunnel. Other schemes which allow more general inputs are not guaranteed to work and the authors do not provide a characterization of the input meshes that can be processed successfully. Moreover, the techniques have difficulty dealing with coarse meshes with many tunnels. In this paper we present the first robust approach to build a map between two meshes of arbitrary unequal genus. We also provide a simplified method for setting the initial alignment between M and M{prime}, reducing reliance on landmarks and allowing the user to select 'landmark tunnels' in addition to the standard landmark vertices. After computing the map, we automatically derive a continuous deformation from M to M{prime} using a variational implicit approach to describe the evolution of non-landmark tunnels. Overall, we achieve a cross parameterization scheme that is provably robust in the sense that it can map M to M{prime} without constraints on their relative genus or on the density of the triangulation with respect to the number of tunnels. To demonstrate the practical effectiveness of our scheme we provide a number of examples of inter-surface parameterizations between meshes of different genus and shape.

  12. Compositional Mapping of a Satellite Surface with a Dust Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Schmidt, J.; Kempf, S.

    2014-12-01

    Measuring the composition of cosmic dust in the vicinity of icy satellites provides unique insight into the physical and chemical conditions at its origin as demonstrated by Cassinis dust detector [4, 3]. Information about the geological activities on and below a moons surface is contained in the types and amounts of organic and inorganic components embedded in the dominant surface material. The basic idea of the proposed compositional mapping [2] is that moons without an atmosphere are wrapped in clouds of dust particles (roughly micron sized) ejected by micro-meteroid impacts from the moons surfaces [1]. The composition of these dust particles can be analysed by an orbiter instrument. The ejecta particles move on ballistic trajectories and most of them recollide with the moon. As a consequence, an almost isotropic dust cloud forms around the moon. From the statistics of the particles in the cloud, one can constrain their location of origin on the surface. Thus, from their composition one can conclude, with given probability, on the composition of a certain part of the surface. In this way, recording a large sample of dust grains with an orbiter, it will be possible to resolve compositional variations on the surface and relate them to topological features.[1] Krueger et al., Nature, 399, 1999.[2] Postberg et al., Planetary and Space Science, 59, 2011.[3] Postberg et al., Nature, 459, 2009.[4] Postberg et al., Icarus, 183, 2006.

  13. Digital map and situation surface: a team-oriented multidisplay workspace for network enabled situation analysis

    NASA Astrophysics Data System (ADS)

    Peinsipp-Byma, E.; Geisler, Jürgen; Bader, Thomas

    2009-05-01

    System concepts for network enabled image-based ISR (intelligence, surveillance, reconnaissance) is the major mission of Fraunhofer IITB's applied research in the area of defence and security solutions. For the TechDemo08 as part of the NATO CNAD POW Defence against terrorism Fraunhofer IITB advanced a new multi display concept to handle the shear amount and high complexity of ISR data acquired by networked, distributed surveillance systems with the objective to support the generation of a common situation picture. Amount and Complexity of ISR data demands an innovative man-machine interface concept for humans to deal with it. The IITB's concept is the Digital Map & Situation Surface. This concept offers to the user a coherent multi display environment combining a horizontal surface for the situation overview from the bird's eye view, an attached vertical display for collateral information and so-called foveatablets as personalized magic lenses in order to obtain high resolved and role-specific information about a focused areaof- interest and to interact with it. In the context of TechDemo08 the Digital Map & Situation Surface served as workspace for team-based situation visualization and analysis. Multiple sea- and landside surveillance components were connected to the system.

  14. Visualizing human brain surface from T1-weighted MR images using texture-mapped triangle meshes.

    PubMed

    Seppä, Mika; Hämäläinen, Matti

    2005-05-15

    We describe a novel method for visualizing brain surface from anatomical magnetic resonance images (MRIs). The method utilizes standard 2D texture mapping capabilities of OpenGL graphics language. It combines the benefits of volume rendering and triangle-mesh rendering, allowing fast and realistic-looking brain surface visualizations. Consequently, relatively low-resolution triangle meshes can be used while the texture images provide the necessary details. The mapping is optimized to provide good texture-image resolution for the triangles with respect to their original sizes in the 3D MRI volume. The actual 2D texture images are generated by depth integration from the original MRI data. Our method adapts to anisotropic voxel sizes without any need to interpolate the volume data into cubic voxels, and it is very well suited for visualizing brain anatomy from standard T(1)-weighted MR images. Furthermore, other OpenGL objects and techniques can be easily combined, for example, to use cut planes, to show other surfaces and objects, and to visualize functional data in addition to the anatomical information.

  15. Landing Site Selection and Surface Traverse Planning using the Lunar Mapping & Modeling Portal

    NASA Astrophysics Data System (ADS)

    Law, E.; Chang, G.; Bui, B.; Sadaqathullah, S.; Kim, R.; Dodge, K.; Malhotra, S.

    2013-12-01

    Introduction: The Lunar Mapping and Modeling Portal (LMMP), is a web-based Portal and a suite of interactive visualization and analysis tools for users to access mapped lunar data products (including image mosaics, digital elevation models, etc.) from past and current lunar missions (e.g., Lunar Reconnaissance Orbiter, Apollo, etc.), and to perform in-depth analyses to support lunar surface mission planning and system design for future lunar exploration and science missions. It has been widely used by many scientists mission planners, as well as educators and public outreach (e.g., Google Lunar XPRICE teams, RESOLVE project, museums etc.) This year, LMMP was used by the Lunar and Planetary Institute (LPI)'s Lunar Exploration internship program to perform lighting analysis and local hazard assessments, such as, slope, surface roughness and crater/boulder distribution to research landing sites and surface pathfinding and traversal. Our talk will include an overview of LMMP, a demonstration of the tools as well as a summary of the LPI Lunar Exploration summer interns' experience in using those tools.

  16. Mapping gray-scale image to 3D surface scanning data by ray tracing

    NASA Astrophysics Data System (ADS)

    Li, Peng; Jones, Peter R. M.

    1997-03-01

    The extraction and location of feature points from range imaging is an important but difficult task in machine vision based measurement systems. There exist some feature points which are not able to be detected from pure geometric characteristics, particularly in those measurement tasks related to the human body. The Loughborough Anthropometric Shadow Scanner (LASS) is a whole body surface scanner based on structured light technique. Certain applications of LASS require accurate location of anthropometric landmarks from the scanned data. This is sometimes impossible from existing raw data because some landmarks do not appear in the scanned data. Identification of these landmarks has to resort to surface texture of the scanned object. Modifications to LASS were made to allow gray-scale images to be captured before or after the object was scanned. Two-dimensional gray-scale image must be mapped to the scanned data to acquire the 3D coordinates of a landmark. The method to map 2D images to the scanned data is based on the colinearity conditions and ray-tracing method. If the camera center and image coordinates are known, the corresponding object point must lie on a ray starting from the camera center and connecting to the image coordinate. By intersecting the ray with the scanned surface of the object, the 3D coordinates of a point can be solved. Experimentation has demonstrated the feasibility of the method.

  17. Variation of winter road surface temperature due to topography and application of Thermal Mapping

    NASA Astrophysics Data System (ADS)

    Shao, J.; Swanson, J. C.; Patterson, R.; Lister, P. J.; McDonald, A. N.

    1997-06-01

    It is known that topography is an important factor controlling the variation of road surface temperature (RST). In order to explore possible relationships between RST and topography, the authors used Thermal Mapping data obtained by a vehicle-mounted thermometer in a mountainous area in Nevada, USA, under different weather conditions in December 1994. The data were validated against the measurements of road surface sensors. After that, a step-wise regression technique is employed to find out possible statistic relationships between RST and altitude at different surveying routes. It was found that the relationships exhibited different characteristics in different climate domains and under different weather types. In most cases, the relationships were non-linear. In order to obtain more information about the cause of the residuals and the variation, the error of regression fitting is related to near-ground meteorological parameters (air temperature, dew point and wind, etc.). This study proved that Thermal Mapping is a reliable and effective method to display spatial variation of road surface temperature.

  18. A MISR-based Surface Roughness Map of the Greenland Ice Sheet

    NASA Astrophysics Data System (ADS)

    Payne, M. C.; Nolin, A. W.

    2008-12-01

    A surface roughness map of the Greenland ice sheet has been constructed from over 400 MISR (Multi-angle Imaging SpectroRadiometer) 670 nm (red band) Cf and Ca ((60.0° forward- and aft-looking) camera images. The use of the red band allows for the maximum spatial resolution (275 m) for MISR, whereas the Ca and Cf camera angles are highly sensitive to surface roughness properties of the ice sheet. The map is a mosaic of normalized difference angular index (NDAI) images acquired during the 2007 sunlit season (April- September). NDAI images have been shown to be a proxy for ice surface roughness in previous work; it is derived by computing a band ratio of MISR's (60° bands. For the northern hemisphere, NDAI is computed by (Ca - Cf)/(Ca + Cf) using red-band radiance or reflectance images. Low values (negative) of NDAI correspond to smoother surface conditions and higher (positive) values correspond to rougher surface conditions. Multiple atmospherically-corrected NDAI images are composited in order to reduce cloud affects over regions where no cloud-free images existed. Images were georeferenced to Equal-Area Scalable Earth Grid (EASE-Grid) projection, and processed and assembled using the ITT ENVI and ESRI ArcGIS software packages. The roughness mosaic reveals detailed features on the ice sheet and associated outlet glaciers. In particular, ice flowlines on outlet glaciers, melt ponds, crevasse regions, and upper glacial regions are clearly distinguishable as distinct roughness zones, suggesting the locations of wet snow, percolation, and dry snow zones. These differentiations allow possible location of the ablation zone versus the accumulation zone, as well as superimposed ice, an important delineation when examining the mass balance status of the ice sheet and a significant factor to consider under current Arctic climate change.

  19. Compositional maps and VIS-IR spectral indicators of Vesta's surface retrieved from VIR hyperspectral data

    NASA Astrophysics Data System (ADS)

    Filacchione, G.; Ammannito, E.; Coradini, A.; De sanctis, M.; Capaccioni, F.; Tosi, F.; Capria, M. T.; Palomba, E.; Magni, G.; Fonte, S.; Carraro, F.; McSween, H. Y.; Raymond, C. A.; Russell, C. T.; McCord, T. B.; Pieters, C. M.; Sunshine, J. M.; Titus, T. N.; Combe, J.; Dawn Science Team

    2011-12-01

    In July 2011, VIR-MS, Visible and Infrared Mapping Spectrometer, aboard the Dawn mission has started a systematic exploration of minor planet Vesta from a 5000 km polar orbit (approach phase). Since then, the instrument has returned hyperspectral cubes in the 0.25-5 μm range with both global and regional views of Vesta's surface. Thanks to the high spatial (250 μrad IFOV, corresponding to a 1.25 km/pixel scale from a 5000 km altitude orbit) and spectral resolution (2 nm/band between 0.25-1 μm and 10 nm/band in the 1-5 μm range), VIR has the capabilities to infer the mineralogical composition of the crust, to discriminate among the very different compositional units, to map their distribution across the surface and to correlate composition with geological features. Since the amount of information provided by each VIR pixel is very large (864 channels), we have developed the VIR Mineralogical Tool (VMT) with the scope of measuring some specific spectral quantities which are tuned to identify the different howarditic, eucritic and diogenitic (HED) components of the crust, thanks to laboratory measurements and ground-based observations of HED meteorites. Continuum levels, VIS-IR band ratios, band I-II properties (center, depth, width, asymmetry), spectral slopes and their mutual correlations are among the principal spectral indicators used to infer the crustal basaltic composition. As a general rule for basaltic materials: 1) the ratio of band I/II areas gives the Band Area Ratio (BAR) which is function of the relative abundance of olivine/orthopyroxene; 2) the value of the I Vs. II band depths is an indicator of the composition, allowing to discriminate among HEDs. An alternative method is based on the correlation between band I width and 0.7-1.3 μm slope or the band I depth Vs. the 0.67-0.95 μm slope; 3) the amount of Fs, Wo and Mg is retrieved from the band I center and band II minima wavelengths; 4) the alteration of the surface, induced by weathering

  20. Mapping Soil Surface Macropores Using Infrared Thermography: An Exploratory Laboratory Study

    PubMed Central

    de Lima, João L. M. P.; Abrantes, João R. C. B.; Silva, Valdemir P.; de Lima, M. Isabel P.; Montenegro, Abelardo A. A.

    2014-01-01

    Macropores and water flow in soils and substrates are complex and are related to topics like preferential flow, nonequilibrium flow, and dual-continuum. Hence, the quantification of the number of macropores and the determination of their geometry are expected to provide a better understanding on the effects of pores on the soil's physical and hydraulic properties. This exploratory study aimed at evaluating the potential of using infrared thermography for mapping macroporosity at the soil surface and estimating the number and size of such macropores. The presented technique was applied to a small scale study (laboratory soil flume). PMID:25371915

  1. Mapping water surface roughness in a shallow, gravel-bed river using hyperspectral imagery

    NASA Astrophysics Data System (ADS)

    Overstreet, B. T.; Legleiter, C. J.

    2014-12-01

    Rapid advances in remote sensing are narrowing the gap between the data available for characterizing physical and biological processes in rivers and the information needed to guide river management decisions. The availability and quality of hyperspectral imagery have increased drastically over the past 20 years and hyperspectral data is now used in a number of different capacities that range from classifying riverine environments to measuring river bathymetry. A fundamental challenge in relating the spectral data from images to biophysical processes is the difficulty of isolating individual contributions to the at-sensor radiance, each associated with a different component of the fluvial environment. In this presentation we describe a method for isolating the contribution of light reflected from the water surface, or sun glint, from a hyperspectral image of a shallow gravel-bed river. We show that isolation and removal of sun glint can improve the accuracy of spectrally-based depth retrieval in cases where sun glint dominates the at-sensor radiance. Observed-vs.-predicted R2 values for depth retrieval improved from 0.56 to 0.68 following sun glint removal. In addition to clarifying the signal associated with the water column and bed, isolating sun glint could unlock important hydraulic information contained within the topography of the water surface. We present data from flume and field experiments suggesting that the intensity of sun glint is a function of water surface roughness. In rivers, water surface roughness depends on local flow hydraulics: depth, velocity, and bed material grain size. To explore this relationship, we coupled maps of image-derived sun glint with hydraulic measurements collected with a kayak-borne acoustic Doppler current profiler along 2 km of the Snake River in Grand Teton National Park. Spatial patterns of sun glint are spatially correlated with field observations of near-surface velocity and depth, suggesting that reach scale hydraulics

  2. Louisiana Ground-Water Map No. 13: Hydrogeology and Potentiometric Surface of the Sparta Aquifer in Northern Louisiana, October 1996

    USGS Publications Warehouse

    Brantly, Jeffrey A.; Seanor, Ronald C.; McCoy, Kaycee L.

    2002-01-01

    This report describes the thickness and areal extent of the Sparta aquifer, identifies sands within the fresh-water extent of the aquifer, and presents data and a map that illustrate the generalized potentiometric surface (water levels) during October 1996. The report includes a detailed geophysical log, structure contour maps, hydrogeologic sections, and hydrographs of water levels in selected wells. The potentiometric surface-map can be used for determining direction of ground-water flow, hydraulic gradients, and the effects of withdrawals on the aquifer.

  3. Louisiana Ground-Water Map No.13: Hydrogeology and Potentiometric Surface of the Sparta Aquifer in Northern Louisiana, October 1996

    USGS Publications Warehouse

    Brantly, Jeffrey A.; Seanor, Ronald C.; McCoy, Kaycee L.

    2002-01-01

    This report describes the thickness and areal extent of the Sparta aquifer, identifies sands within the fresh-water extent of the aquifer, and presents data and a map that illustrate the generalized potentiometric surface (water levels) during October 1996. The report includes a detailed geophysical log, structure contour maps, hydrogeologic sections, and hydrographs of water levels in selected wells. The potentiometric surface-map can be used for determining direction of ground-water flow, hydraulic gradients, and the effects of withdrawals on the aquifer.

  4. Agriculture pest and disease risk maps considering MSG satellite data and land surface temperature

    NASA Astrophysics Data System (ADS)

    Marques da Silva, J. R.; Damásio, C. V.; Sousa, A. M. O.; Bugalho, L.; Pessanha, L.; Quaresma, P.

    2015-06-01

    Pest risk maps for agricultural use are usually constructed from data obtained from in-situ meteorological weather stations, which are relatively sparsely distributed and are often quite expensive to install and difficult to maintain. This leads to the creation of maps with relatively low spatial resolution, which are very much dependent on interpolation methodologies. Considering that agricultural applications typically require a more detailed scale analysis than has traditionally been available, remote sensing technology can offer better monitoring at increasing spatial and temporal resolutions, thereby, improving pest management results and reducing costs. This article uses ground temperature, or land surface temperature (LST), data distributed by EUMETSAT/LSASAF (with a spatial resolution of 3 × 3 km (nadir resolution) and a revisiting time of 15 min) to generate one of the most commonly used parameters in pest modeling and monitoring: "thermal integral over air temperature (accumulated degree-days)". The results show a clear association between the accumulated LST values over a threshold and the accumulated values computed from meteorological stations over the same threshold (specific to a particular tomato pest). The results are very promising and enable the production of risk maps for agricultural pests with a degree of spatial and temporal detail that is difficult to achieve using in-situ meteorological stations.

  5. Mapping Impervious Surfaces Globally at 30m Resolution Using Global Land Survey Data

    NASA Technical Reports Server (NTRS)

    DeColstoun, Eric Brown; Huang, Chengquan; Tan, Bin; Smith, Sarah Elizabeth; Phillips, Jacqueline; Wang, Panshi; Ling, Pui-Yu; Zhan, James; Li, Sike; Taylor, Michael P.; Wolfe, Robert E.; Tilton, James C.

    2013-01-01

    Impervious surfaces, mainly artificial structures and roads, cover less than 1% of the world's land surface (1.3% over USA). Regardless of the relatively small coverage, impervious surfaces have a significant impact on the environment. They are the main source of the urban heat island effect, and affect not only the energy balance, but also hydrology and carbon cycling, and both land and aquatic ecosystem services. In the last several decades, the pace of converting natural land surface to impervious surfaces has increased. Quantitatively monitoring the growth of impervious surface expansion and associated urbanization has become a priority topic across both the physical and social sciences. The recent availability of consistent, global scale data sets at 30m resolution such as the Global Land Survey from the Landsat satellites provides an unprecedented opportunity to map global impervious cover and urbanization at this resolution for the first time, with unprecedented detail and accuracy. Moreover, the spatial resolution of Landsat is absolutely essential to accurately resolve urban targets such a buildings, roads and parking lots. With long term GLS data now available for the 1975, 1990, 2000, 2005 and 2010 time periods, the land cover/use changes due to urbanization can now be quantified at this spatial scale as well. In the Global Land Survey - Imperviousness Mapping Project (GLS-IMP), we are producing the first global 30 m spatial resolution impervious cover data set. We have processed the GLS 2010 data set to surface reflectance (8500+ TM and ETM+ scenes) and are using a supervised classification method using a regression tree to produce continental scale impervious cover data sets. A very large set of accurate training samples is the key to the supervised classifications and is being derived through the interpretation of high spatial resolution (approx. 2 m or less) commercial satellite data (Quickbird and Worldview2) available to us through the unclassified

  6. Mapping Impervious Surfaces Globally at 30m Resolution Using Landsat Global Land Survey Data

    NASA Astrophysics Data System (ADS)

    Brown de Colstoun, E.; Huang, C.; Wolfe, R. E.; Tan, B.; Tilton, J.; Smith, S.; Phillips, J.; Wang, P.; Ling, P.; Zhan, J.; Xu, X.; Taylor, M. P.

    2013-12-01

    Impervious surfaces, mainly artificial structures and roads, cover less than 1% of the world's land surface (1.3% over USA). Regardless of the relatively small coverage, impervious surfaces have a significant impact on the environment. They are the main source of the urban heat island effect, and affect not only the energy balance, but also hydrology and carbon cycling, and both land and aquatic ecosystem services. In the last several decades, the pace of converting natural land surface to impervious surfaces has increased. Quantitatively monitoring the growth of impervious surface expansion and associated urbanization has become a priority topic across both the physical and social sciences. The recent availability of consistent, global scale data sets at 30m resolution such as the Global Land Survey from the Landsat satellites provides an unprecedented opportunity to map global impervious cover and urbanization at this resolution for the first time, with unprecedented detail and accuracy. Moreover, the spatial resolution of Landsat is absolutely essential to accurately resolve urban targets such a buildings, roads and parking lots. With long term GLS data now available for the 1975, 1990, 2000, 2005 and 2010 time periods, the land cover/use changes due to urbanization can now be quantified at this spatial scale as well. In the Global Land Survey - Imperviousness Mapping Project (GLS-IMP), we are producing the first global 30 m spatial resolution impervious cover data set. We have processed the GLS 2010 data set to surface reflectance (8500+ TM and ETM+ scenes) and are using a supervised classification method using a regression tree to produce continental scale impervious cover data sets. A very large set of accurate training samples is the key to the supervised classifications and is being derived through the interpretation of high spatial resolution (~2 m or less) commercial satellite data (Quickbird and Worldview2) available to us through the unclassified

  7. Obtaining the wavefront phase maps of free form surfaces: using the least squares algorithm

    NASA Astrophysics Data System (ADS)

    Villalobos-Mendoza, B.; Aguirre-Aguirre, D.; Granados-Agustín, F.; Cornejo-Rodríguez, A.

    2015-01-01

    In this work is presented the validation of the least squares algorithm proposed by Morgan (1982) and Greivenkamp (1984), to obtain the wavefront phase maps of a free form surface. The validation was made by simulating the synthetic interferograms of a free form surface using a Bessel function, each interferogram was simulated with a phase-shifting of π/20. This algorithm is applied to the experimental interferograms that are obtained in a Twyman-Green interferometer where the phase shifting is achieved by using a SLM (Spatial Light Modulator) that is placed in one of its arms; the phase shifts are achieved by displaying all the gray levels from 0 to 255 in the SLM. The phase shifts that are performed in this experimental setup are lower than π/4, therefore the conventional algorithms cannot be applied.

  8. Mapping the anode surface-electrolyte interphase: investigating a life limiting process of lithium primary batteries.

    PubMed

    Bock, David C; Tappero, Ryan V; Takeuchi, Kenneth J; Marschilok, Amy C; Takeuchi, Esther S

    2015-03-11

    Cathode solubility in batteries can lead to decreased and unpredictable long-term battery behavior due to transition metal deposition on the negative electrode such that it no longer supports high current. Analysis of negative electrodes from cells containing vanadium oxide or phosphorus oxide based cathode systems retrieved after long-term testing was conducted. This report demonstrates the use of synchrotron based X-ray microfluorescence (XRμF) to map negative battery electrodes in conjunction with microbeam X-ray absorption spectroscopy (μXAS) to determine the oxidation states of the metal centers resident in the solid electrolyte interphase (SEI) and at the electrode surface. Based on the empirical findings, a conceptual model for the location of metal ions in the SEI and their role in impacting lithium ion mobility at the electrode surfaces is proposed.

  9. Mesoscale mapping of available solar energy at the earth's surface by use of satellites

    NASA Technical Reports Server (NTRS)

    Hiser, H. W.; Senn, H. V.

    1980-01-01

    A method is presented for use of cloud images in the visual spectrum from the SMS/GOES geostationary satellites to determine the hourly distribution of sunshine on the mesoscale. Cloud coverage and density as a function of time of day and season are evaluated through the use of digital data processing techniques. Seasonal geographic distributions of cloud cover/sunshine are converted to joules of solar radiation received at the earth's surface through relationships developed from long-term measurements of these two parameters at six widely distributed stations. The technique can be used to generate maps showing the geographic distribution of total solar radiation on the mesoscale which is received at the earth's surface.

  10. Descriptive Characteristics of Surface Water Quality in Hong Kong by a Self-Organising Map

    PubMed Central

    An, Yan; Zou, Zhihong; Li, Ranran

    2016-01-01

    In this study, principal component analysis (PCA) and a self-organising map (SOM) were used to analyse a complex dataset obtained from the river water monitoring stations in the Tolo Harbor and Channel Water Control Zone (Hong Kong), covering the period of 2009–2011. PCA was initially applied to identify the principal components (PCs) among the nonlinear and complex surface water quality parameters. SOM followed PCA, and was implemented to analyze the complex relationships and behaviors of the parameters. The results reveal that PCA reduced the multidimensional parameters to four significant PCs which are combinations of the original ones. The positive and inverse relationships of the parameters were shown explicitly by pattern analysis in the component planes. It was found that PCA and SOM are efficient tools to capture and analyze the behavior of multivariable, complex, and nonlinear related surface water quality data. PMID:26761018

  11. Solvation thermodynamic mapping of molecular surfaces in AmberTools: GIST.

    PubMed

    Ramsey, Steven; Nguyen, Crystal; Salomon-Ferrer, Romelia; Walker, Ross C; Gilson, Michael K; Kurtzman, Tom

    2016-08-05

    The expulsion of water from surfaces upon molecular recognition and nonspecific association makes a major contribution to the free energy changes of these processes. In order to facilitate the characterization of water structure and thermodynamics on surfaces, we have incorporated Grid Inhomogeneous Solvation Theory (GIST) into the CPPTRAJ toolset of AmberTools. GIST is a grid-based implementation of Inhomogeneous Fluid Solvation Theory, which analyzes the output from molecular dynamics simulations to map out solvation thermodynamic and structural properties on a high-resolution, three-dimensional grid. The CPPTRAJ implementation, called GIST-cpptraj, has a simple, easy-to-use command line interface, and is open source and freely distributed. We have also developed a set of open-source tools, called GISTPP, which facilitate the analysis of GIST output grids. Tutorials for both GIST-cpptraj and GISTPP can be found at ambermd.org. © 2016 Wiley Periodicals, Inc.

  12. An approach for mapping large-area impervious surfaces: Synergistic use of Landsat-7 ETM+ and high spatial resolution imagery

    USGS Publications Warehouse

    Yang, L.; Huang, C.; Homer, C.G.; Wylie, B.K.; Coan, M.J.

    2003-01-01

    A wide range of urban ecosystem studies, including urban hydrology, urban climate, land use planning, and resource management, require current and accurate geospatial data of urban impervious surfaces. We developed an approach to quantify urban impervious surfaces as a continuous variable by using multisensor and multisource datasets. Subpixel percent impervious surfaces at 30-m resolution were mapped using a regression tree model. The utility, practicality, and affordability of the proposed method for large-area imperviousness mapping were tested over three spatial scales (Sioux Falls, South Dakota, Richmond, Virginia, and the Chesapeake Bay areas of the United States). Average error of predicted versus actual percent impervious surface ranged from 8.8 to 11.4%, with correlation coefficients from 0.82 to 0.91. The approach is being implemented to map impervious surfaces for the entire United States as one of the major components of the circa 2000 national land cover database.

  13. Combining geomorphological mapping and near surface geophysics (GPR and ERT) to study piping systems

    NASA Astrophysics Data System (ADS)

    Bernatek-Jakiel, Anita; Kondracka, Marta

    2016-12-01

    This paper aims to provide a more comprehensive characterization of piping systems in mountainous areas under a temperate climate using geomorphological mapping and geophysical methods (electrical resistivity tomography - ERT and ground penetrating radar - GPR). The significance of piping in gully formation and hillslope hydrology has been discussed for many years, and most of the studies are based on surface investigations. However, it seems that most surface investigations underestimate this subsurface process. Therefore, our purpose was to estimate the scale of piping activity based on both surface and subsurface investigations. We used geophysical methods to detect the boundary of lateral water movement fostering pipe development and recognize the internal structure of the underlying materials. The survey was carried out in the Bereźnica Wyżna catchment, in the Bieszczady Mountains. (Eastern Carpathians, Poland), where pipes develop in Cambisols at a mean depth of about 0.7-0.8 m. The geophysical techniques that were used are shown to be successful in identifying pipes. GPR data suggest that the density of piping systems is much larger than that detectible from surface observations alone. Pipe length can be > 6.5-9.2% (maximum = 49%) higher than what surface mapping suggests. Thus, the significance of piping in hillslope hydrology and gully formation can be greater than previously assumed. These results also draw attention to the scale of piping activity in the Carpathians, where this process has been neglected for many years. The ERT profiles reveal areas affected by piping as places of higher resistivity values, which are an effect of a higher content of air-filled pores (due to higher soil porosity, intense biological activity, and well-developed soil structure). In addition, the ERT profiles show that the pipes in the study area develop at the soil-bedrock interface, probably above the layers of shales or mudstones which create a water restrictive layer

  14. Map showing flood and surface water information in the Sugar House quadrangle, Salt Lake County, Utah

    USGS Publications Warehouse

    Van Horn, Richard; Fields, F.K.

    1974-01-01

    In the past man has built on land that might be covered by floodwaters, with little consideration of the consequences. The result has been disastrous to those in the path of floodwaters and has cost the loss of thousands of lives and untold billions of dollars in property damage in the United States. Salt Lake County, of which the Sugar House quadrangle is a part, has had many floods in the past and can be expected to have more in the future. Construction has taken place in filled or dried-up marshes and lakes, in spring areas, and even in stream channels. Lack of prior knowledge of these and other forms of surface water (water at the surface of the ground) can increase construction and maintenance costs significantly.The map shows the area that probably will be covered by floods at least once in every 100 years on the long-term average (unit IRF, intermediate regional flood), the area that probably will be covered by floods from the worst possible combination of very wet weather and high streamflow reasonably expected of the area (unit SPF, standard project flood), the mapped extent of streamflow by channel shifting or flooding in the past 5,000 years (unit fa), and the probable maximum extent of damaging flash floods and mudflows from small valleys in the Wasatch Range. The map also shows the location of water at the surface of the ground: lakes, streams, springs, weep holes, canals, and reservoirs. Lakes and marshes that existed within the past 100 years, but now are drained, filled, or dried up, are also shown.The following examples show that the presence of water can be desirable or undesirable, depending on how the water occurs. Floods, the most spectacular form of surface water, may result in great property damage and loss of life. Lakes normally are beneficial, in that they may support plant growth and provide habitats for fish and other wildlife, provide water for livestock, and can be used for recreation. Springs may or may not be desirable: they may

  15. Mapping drug distribution in brain tissue using liquid extraction surface analysis mass spectrometry imaging.

    PubMed

    Swales, John G; Tucker, James W; Spreadborough, Michael J; Iverson, Suzanne L; Clench, Malcolm R; Webborn, Peter J H; Goodwin, Richard J A

    2015-10-06

    Liquid extraction surface analysis mass spectrometry (LESA-MS) is a surface sampling technique that incorporates liquid extraction from the surface of tissue sections with nanoelectrospray mass spectrometry. Traditional tissue analysis techniques usually require homogenization of the sample prior to analysis via high-performance liquid chromatography mass spectrometry (HPLC-MS), but an intrinsic weakness of this is a loss of all spatial information and the inability of the technique to distinguish between actual tissue penetration and response caused by residual blood contamination. LESA-MS, in contrast, has the ability to spatially resolve drug distributions and has historically been used to profile discrete spots on the surface of tissue sections. Here, we use the technique as a mass spectrometry imaging (MSI) tool, extracting points at 1 mm spatial resolution across tissue sections to build an image of xenobiotic and endogenous compound distribution to assess drug blood-brain barrier penetration into brain tissue. A selection of penetrant and "nonpenetrant" drugs were dosed to rats via oral and intravenous administration. Whole brains were snap-frozen at necropsy and were subsequently sectioned prior to analysis by matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) and LESA-MSI. MALDI-MSI, as expected, was shown to effectively map the distribution of brain penetrative compounds but lacked sufficient sensitivity when compounds were marginally penetrative. LESA-MSI was used to effectively map the distribution of these poorly penetrative compounds, highlighting its value as a complementary technique to MALDI-MSI. The technique also showed benefits when compared to traditional homogenization, particularly for drugs that were considered nonpenetrant by homogenization but were shown to have a measurable penetration using LESA-MSI.

  16. First measurements of error fields on W7-X using flux surface mapping

    NASA Astrophysics Data System (ADS)

    Lazerson, Samuel A.; Otte, Matthias; Bozhenkov, Sergey; Biedermann, Christoph; Pedersen, Thomas Sunn; the W7-X Team

    2016-10-01

    Error fields have been detected and quantified using the flux surface mapping diagnostic system on Wendelstein 7-X (W7-X). A low-field ‘{\\rlap- \\iota} =1/2 ’ magnetic configuration ({\\rlap- \\iota} =\\iota /2π ), sensitive to error fields, was developed in order to detect their presence using the flux surface mapping diagnostic. In this configuration, a vacuum flux surface with rotational transform of n/m  =  1/2 is created at the mid-radius of the vacuum flux surfaces. If no error fields are present a vanishingly small n/m  =  5/10 island chain should be present. Modeling indicates that if an n  =  1 perturbing field is applied by the trim coils, a large n/m  =  1/2 island chain will be opened. This island chain is used to create a perturbation large enough to be imaged by the diagnostic. Phase and amplitude scans of the applied field allow the measurement of a small ∼ 0.04 m intrinsic island chain with a {{130}\\circ} phase relative to the first module of the W7-X experiment. These error fields are determined to be small and easily correctable by the trim coil system. Notice: This manuscript has been authored by Princeton University under Contract Number DE-AC02-09CH11466 with the U.S. Department of Energy. The publisher, by accepting the article for publication acknowledges, that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes.

  17. Automatic mapping of urban areas from Landsat data using impervious surface fraction algorithm

    NASA Astrophysics Data System (ADS)

    Nguyen, S. T.; Chen, C. F.; Chen, C. R.

    2014-12-01

    Urbanization is a result of aggregation of people in urban areas that can help advance socioeconomic development and pull out people from the poverty line. However, if not monitored well, it can also lead to loss of farmlands, natural forests as well as to societal impacts including burgeoning growth of slums, pollution, and crime. Thus, spatiotemporal information that shapes the urbanization is thus critical to the process of urban planning. The overall objective of this study is to develop an impervious surface fraction algorithm (ISFA) for automatically mapping urban areas from Landsat data. We processed the data for 1986, 2001 and 2014 to trace the multi-decadal spatiotemporal change of Honduran capital city using a three-step procedure: (1) data pre-processing to perform image normalization as well as to produce the difference in the values (DVSS) between the simple ratio (SR) of green and shortwave bands and the soil adjust vegetation index (SAVI), (2) quantification of urban areas using ISFA, and (3) accuracy assessment of mapping results using the ground reference data constructed using land-cover maps and FORMOSAT-2 imagery. The mapping accuracy assessment was performed for 2001 and 2014 by comparing with the ground reference data indicated satisfactory results with the overall accuracies and Kappa coefficients generally higher than 90% and 0.8, respectively. When examining the urbanization between these years, it could be observed that the urban area was significantly expanded from 1986 to 2014, mainly driven by two factors of rapid population growth and socioeconomic development. This study eventually leads to a realization of the merit of using ISFA for multi-decadal monitoring of the urbanization of Honduran capital city from Landsat data. Results from this research can be used by urban planners as a general indicator to quantify urban change and environmental impacts. The methods were thus transferable to monitor urban growth in cities and their peri

  18. Potentiometric Surface Map of the Lower Patapsco Aquifer in Southern Maryland, September, 2003

    USGS Publications Warehouse

    Curtin, Stephen E.; Andreasen, David C.; Wheeler, Judith C.

    2005-01-01

    This report presents a map showing the potentiometric surface of the Lower Patapsco aquifer in the Patapsco Formation of Lower Cretaceous age in Southern Maryland during September 2003. The map is based on water-level measurements in 66 wells. The highest measured water level was 112 feet above sea level near the northwestern boundary and outcrop area of the aquifer in northern Prince Georges County. From this area, the potentiometric surface declined towards well fields at Severndale, Arnold, and Annapolis. The measured ground-water levels were 86 feet below sea level at Severndale, 41 feet below sea level at Arnold, and 39 feet below sea level a few miles west of Annapolis. There was also a cone of depression covering a large area in Charles County that includes Waldorf, LaPlata, Indian Head, and the Morgantown powerplant. The ground-water levels measured were as low as 165 feet below sea level at Waldorf, 135 feet below sea level at LaPlata, 114 feet below sea level at Indian Head, and 92 feet below sea level at the Morgantown powerplant.

  19. Mapping Surface Soil Organic Carbon for Crop Fields with Remote Sensing

    NASA Technical Reports Server (NTRS)

    Chen, Feng; Kissel, David E.; West, Larry T.; Rickman, Doug; Luvall, J. C.; Adkins, Wayne

    2004-01-01

    The organic C concentration of surface soil can be used in agricultural fields to vary crop production inputs. Organic C is often highly spatially variable, so that maps of soil organic C can be used to vary crop production inputs using precision farming technology. The objective of this research was to demonstrate the feasibility of mapping soil organic C on three fields, using remotely sensed images of the fields with a bare surface. Enough soil samples covering the range in soil organic C must be taken from each field to develop a satisfactory relationship between soil organic C content and image reflectance values. The number of soil samples analyzed in the three fields varied from 22 to 26. The regression equations differed between fields, but gave highly significant relationships with R2 values of 0.93, 0.95, and 0.89 for the three fields. A comparison of predicted and measured values of soil organic C for an independent set of 2 soil samples taken on one of the fields gave highly satisfactory results, with a comparison equation of % organic C measured + 1.02% organic C predicted, with r2 = 0.87.

  20. Data processing for fabrication of GMT primary segments: raw data to final surface maps

    NASA Astrophysics Data System (ADS)

    Tuell, Michael T.; Hubler, William; Martin, Hubert M.; West, Steven C.; Zhou, Ping

    2014-07-01

    The Giant Magellan Telescope (GMT) primary mirror is a 25 meter f/0.7 surface composed of seven 8.4 meter circular segments, six of which are identical off-axis segments. The fabrication and testing challenges with these severely aspheric segments (about 14 mm of aspheric departure, mostly astigmatism) are well documented. Converting the raw phase data to useful surface maps involves many steps and compensations. They include large corrections for: image distortion from the off-axis null test; misalignment of the null test; departure from the ideal support forces; and temperature gradients in the mirror. The final correction simulates the active-optics correction that will be made at the telescope. Data are collected and phase maps are computed in 4D Technology's 4SightTM software. The data are saved to a .h5 (HDF5) file and imported into MATLAB® for further analysis. A semi-automated data pipeline has been developed to reduce the analysis time as well as reducing the potential for error. As each operation is performed, results and analysis parameters are appended to a data file, so in the end, the history of data processing is embedded in the file. A report and a spreadsheet are automatically generated to display the final statistics as well as how each compensation term varied during the data acquisition. This gives us valuable statistics and provides a quick starting point for investigating atypical results.

  1. A new capture fraction method to map how pumpage affects surface water flow

    USGS Publications Warehouse

    Leake, S.A.; Reeves, H.W.; Dickinson, J.E.

    2010-01-01

    All groundwater pumped is balanced by removal of water somewhere, initially from storage in the aquifer and later from capture in the form of increase in recharge and decrease in discharge. Capture that results in a loss of water in streams, rivers, and wetlands now is a concern in many parts of the United States. Hydrologists commonly use analytical and numerical approaches to study temporal variations in sources of water to wells for select points of interest. Much can be learned about coupled surface/groundwater systems, however, by looking at the spatial distribution of theoretical capture for select times of interest. Development of maps of capture requires (1) a reasonably well-constructed transient or steady state model of an aquifer with head-dependent flow boundaries representing surface water features or evapotranspiration and (2) an automated procedure to run the model repeatedly and extract results, each time with a well in a different location. This paper presents new methods for simulating and mapping capture using three-dimensional groundwater flow models and presents examples from Arizona, Oregon, and Michigan. Journal compilation ?? 2010 National Ground Water Association. No claim to original US government works.

  2. Atmospheric Drivers of Greenland Surface Melt Revealed by Self Organizing Maps

    NASA Astrophysics Data System (ADS)

    Mioduszewski, J.; Rennermalm, A. K.; Hammann, A. C.; Tedesco, M.; Noble, E. U.; Stroeve, J. C.; Mote, T. L.

    2015-12-01

    Recent acceleration in summer surface melt on the Greenland ice sheet (GrIS) has occurred concurrently with a rapidly warming Arctic and has been connected to persistent, anomalous circulation patterns over Greenland. To identify patterns that favor enhanced GrIS surface melt and their decadal changes, we first develop a summer Arctic synoptic climatology by employing a nonlinear classification technique known as the self organizing map (SOM). This is applied to daily JJA sea level pressure (SLP) and 500 hPa geopotential height fields obtained from the Modern Era Retrospective Analysis for Research and Applications (MERRA) reanalysis product from 1979 to 2014. Model output from Modèle Atmosphérique Régional (MAR) is used to relate meteorological conditions and subsequent Greenland surface melt anomalies to particular circulation regimes. Results demonstrate that circulation patterns featuring positive SLP anomalies from Greenland to the Beaufort Sea support the largest positive surface melt anomalies, particularly over western Greenland. These patterns facilitate strong meridional transport of heat and moisture, contrasted by a dominant zonal flow across the North Atlantic during periods of low surface melt. Additionally, composites of energy balance components reveal that melt events are favored under clear conditions generating positive shortwave radiation anomalies rather than increased downwelling longwave radiation occurring with increased cloud cover. Sea surface temperature anomalies suggest that there may be a linkage between surface melt and recent sea ice loss around Greenland, though a causal relationship is not established. We assess decadal shifts in the SOM nodes, finding an increased frequency of upper level patterns favoring higher 500 hPa geopotential heights primarily over Greenland. The observed increases in GrIS melt through the time period coincides with this shift in SOM node frequency.

  3. AVIRIS Land-Surface Mapping in Support of the Boreal Ecosystem-Atmosphere Study (BOREAS)

    NASA Technical Reports Server (NTRS)

    Roberts, Dar A.; Gamon, John; Keightley, Keir; Prentiss, Dylan; Reith, Ernest; Green, Robert

    2001-01-01

    A key scientific objective of the original Boreal Ecosystem-Atmospheric Study (BOREAS) field campaign (1993-1996) was to obtain the baseline data required for modeling and predicting fluxes of energy, mass, and trace gases in the boreal forest biome. These data sets are necessary to determine the sensitivity of the boreal forest biome to potential climatic changes and potential biophysical feedbacks on climate. A considerable volume of remotely-sensed and supporting field data were acquired by numerous researchers to meet this objective. By design, remote sensing and modeling were considered critical components for scaling efforts, extending point measurements from flux towers and field sites over larger spatial and longer temporal scales. A major focus of the BOREAS follow-on program is concerned with integrating the diverse remotely sensed and ground-based data sets to address specific questions such as carbon dynamics at local to regional scales. The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) has the potential of contributing to BOREAS through: (1) accurate retrieved apparent surface reflectance; (2) improved landcover classification; and (3) direct assessment of biochemical/biophysical information such as canopy liquid water and chlorophyll concentration through pigment fits. In this paper, we present initial products for major flux tower sites including: (1) surface reflectance of dominant cover types; (2) a land-cover classification developed using spectral mixture analysis (SMA) and Multiple Endmember Spectral Mixture Analysis (MESMA); and (3) liquid water maps. Our goal is to compare these land-cover maps to existing maps and to incorporate AVIRIS image products into models of photosynthetic flux.

  4. Mapping the Moho with seismic surface waves: A review, resolution analysis, and recommended inversion strategies

    NASA Astrophysics Data System (ADS)

    Lebedev, Sergei; Adam, Joanne M.-C.; Meier, Thomas

    2013-12-01

    The strong sensitivity of seismic surface waves to the Moho is evident from a mere visual inspection of their dispersion curves or waveforms. Rayleigh and Love waves have been used to study the Earth's crust since the early days of modern seismology. Yet, strong trade-offs between the Moho depth and crustal and mantle structure in surface-wave inversions prompted doubts regarding their capacity to resolve the Moho. Here, we review surface-wave studies of the Moho, with a focus on early work, and then use model-space mapping to establish the waves' sensitivity to the Moho depth and the resolution of their inversion for it. If seismic wavespeeds within the crust and upper mantle are known, then Moho-depth variations of a few kilometres produce large (> 1%) perturbations in phase velocities. However, in inversions of surface-wave data with no a priori information (wavespeeds not known), strong Moho-depth/shear-speed trade-offs will mask ~ 90% of the Moho-depth signal, with remaining phase-velocity perturbations ~ 0.1% only. In order to resolve the Moho with surface waves alone, errors in the data must thus be small (up to ~ 0.2% for resolving continental Moho). With larger errors, Moho-depth resolution is not warranted and depends on error distribution with period. An effective strategy for the inversion of surface-wave data alone for the Moho depth is to, first, constrain the crustal and upper-mantle structure by inversion in a broad period range and then determine the Moho depth in inversion in a narrow period range most sensitive to it, with the first-step results used as reference. Prior information on crustal and mantle structure reduces the trade-offs and thus enables resolving the Moho depth with noisier data; such information should be used whenever available. Joint analysis or inversion of surface-wave and other data (receiver functions, topography, gravity) can reduce uncertainties further and facilitate Moho mapping.

  5. Using ground-based geophysics to rapidly and accurately map sub-surface acidity

    NASA Astrophysics Data System (ADS)

    Wong, Vanessa; Triantafilis, John; Johnston, Scott; Nhan, Terence; Page, Donald; Wege, Richard; Hirst, Phillip; Slavich, Peter

    2013-04-01

    Globally, large areas of coastal and estuarine floodplains are underlain by sulfidic sediments and acid sulfate soils (ASS). These soils can be environmentally hazardous due to their high acidity and large pool of potentially mobile metals. The floodplains are characterised by high spatial and temporal heterogeneity. On coastal floodplains, ASS are of moderate to high salinity, with salts derived mainly from either connate marine sources or oxidation of biogenic sulfides and the subsequent increases in soluble ions (e.g. SO42-) and acidity that follow oxidation. Enhanced acidity also increases the mobilisation of pH-sensitive trace metals such as Fe, Al, Mn, Zn and Ni and contributes to increasing apparent salinity. Ground-based geophysics using electromagnetic (EM) induction techniques have been used successfully and extensively to rapidly map soils for salinity management and precision agriculture. EM induction techniques measure apparent soil electrical conductivity (ECa), which is a function of salinity, clay content, water content, soil mineralogy and temperature to determine the spatial distribution of sub-surface conductivity. In this study, we used ECa as a proxy to map the surface and sub-surface spatial distribution of ASS and associated acidic groundwater. Three EM instruments were used, EM38, DUALEM-421 and EM34, which focus on different depth layers, in a survey of a coastal floodplain in eastern Australia. The EM surveys were calibrated with limited soil sampling and analysis (pH, EC, soluble and exchangeable salts and metals, particle size and titratable actual acidity (TAA)). Using fuzzy k-means clustering analysis, the EM38 and elevation data, from a digital elevation model, clearly identified three classes in the near-surface (0-2m) layers: i) levee soils, ii) fluvial sediment capping and iii) ASS (Fig. 4). Increasing the number of classes did not alter the classes identified. Joint inversion of the DUALEM-421 and EM34 data also identified

  6. Map showing the potentiometric surface of the Magothy Aquifer in southern Maryland, September 1979

    USGS Publications Warehouse

    Mack, Frederick K.; Wheeler, J.C.; Curtin, Stephen E.

    1980-01-01

    This map is based on measurements made on a network of 77 observation wells in southern Maryland. Highest levels of the potentiometric surface, 63 to 67 feet above sea level, were measured near the outcrop or subcrop of the aquifer in topographically high areas of Anne Arundel and Prince Georges Counties. The surface slopes to the southeast to about 5 feet above sea level along much of the western shore of the Chesapeake Bay. Four separate, distinct, and extensive cones of depression have developed in the surface around the well fields of the city of Annapolis, Broadneck, town of Waldorf, and Chalk Point. Several square miles of each cone are below sea level and in localized areas at Chalk Point and Waldorf, the surface is 40 to 50 feet below sea level. The network of wells was developed as part of the cooperative program between the U.S. Geological Survey, the Maryland Geological Survey, and the Maryland Energy and Coastal Zone Administration. (USGS)

  7. Mapping surface soil moisture using an aircraft-based passive microwave instrument: algorithm and example

    NASA Astrophysics Data System (ADS)

    Jackson, T. J.; Le Vine, David E.

    1996-10-01

    Microwave remote sensing at L-band (21 cm wavelength) can provide a direct measurement of the surface soil moisture for a range of cover conditions and within reasonable error bounds. Surface soil moisture observations are rare and, therefore, the use of these data in hydrology and other disciplines has not been fully explored or developed. Without satellite-based observing systems, the only way to collect these data in large-scale studies is with an aircraft platform. Recently, aircraft systems such as the push broom microwave radiometer (PBMR) and the electronically scanned thinned array radiometer (ESTAR) have been developed to facilitate such investigations. In addition, field experiments have attempted to collect the passive microwave data as part of an integrated set of hydrologic data. One of the most ambitious of these investigations was the Washita'92 experiment. Preliminary analysis of these data has shown that the microwave observations are indicative of deterministic spatial and temporal variations in the surface soil moisture. Users of these data should be aware of a number of issues related to using aircraft-based systems and practical approaches to applying soil moisture estimation algorithms to large data sets. This paper outlines the process of mapping surface soil moisture from an aircraft-based passive microwave radiometer system for the Washita'92 experiment.

  8. Hydrography change detection: the usefulness of surface channels derived From LiDAR DEMs for updating mapped hydrography

    USGS Publications Warehouse

    Poppenga, Sandra K.; Gesch, Dean B.; Worstell, Bruce B.

    2013-01-01

    The 1:24,000-scale high-resolution National Hydrography Dataset (NHD) mapped hydrography flow lines require regular updating because land surface conditions that affect surface channel drainage change over time. Historically, NHD flow lines were created by digitizing surface water information from aerial photography and paper maps. Using these same methods to update nationwide NHD flow lines is costly and inefficient; furthermore, these methods result in hydrography that lacks the horizontal and vertical accuracy needed for fully integrated datasets useful for mapping and scientific investigations. Effective methods for improving mapped hydrography employ change detection analysis of surface channels derived from light detection and ranging (LiDAR) digital elevation models (DEMs) and NHD flow lines. In this article, we describe the usefulness of surface channels derived from LiDAR DEMs for hydrography change detection to derive spatially accurate and time-relevant mapped hydrography. The methods employ analyses of horizontal and vertical differences between LiDAR-derived surface channels and NHD flow lines to define candidate locations of hydrography change. These methods alleviate the need to analyze and update the nationwide NHD for time relevant hydrography, and provide an avenue for updating the dataset where change has occurred.

  9. Quantitative Mapping of Surface Texture on the Northern Polar Residual Cap of Mars

    NASA Astrophysics Data System (ADS)

    Milkovich, S. M.; Byrne, S.; Russell, P. S.

    2010-12-01

    The northern polar residual cap (NPRC) of Mars is a water ice deposit with a rough surface made up of pits, knobs, and linear depressions on scales of tens of meters [1]. This roughness manifests as a series of bright and dark patches in visible images. Spectral data indicate that the surface of the NPRC is composed of large-grained (and therefore old) water ice. Due to the presence of this old ice, it is thought that the NPRC is in a current state of net loss of material [2]. The NPRC provides a link between the current martian climate and the historical climate recorded within the layers of the underlying north polar layered deposits. By characterizing and mapping the variations in surface texture of the NPRC, we seek to understand what factors (distance from the pole, GCM and mesoscale wind direction predictions, etc) are currently at work in resurfacing the deposit, and may have been at work in shaping the layers below. Maps of NPRC texture wavelength and orientation are being produced from HiRISE images. Two-dimensional Fourier analysis is performed upon a 256 meter x 256 meter region (corresponding to 512 x 512 pixels in 0.5 cm/pxl images, or 1024 x 1024 pixels in 0.25 cm/pxl images) within each image analyzed. The dominant wavelength of the resulting peak power spectrum corresponds to the average size of a pit-knob pair in the image, and so is a proxy for the scale of the surface roughness. The orientation of the surface roughness (i.e., the orientation of a chain of pits and mounds) is measured from a narrow range of wavelengths encompassing the dominant wavelength. We will report on how the dominant wavelengths and orientations of this surface texture vary with location and what that implies for the processes currently shaping this landscape. [1] P. C. Thomas et al, Nature 404, 161-164, 2000 [2]Y. Langevin et al, Science 307, 5715, 1581-1584, 2005.

  10. Evaluation of a Moderate Resolution, Satellite-Based Impervious Surface Map Using an Independent, High-Resolution Validation Dataset

    EPA Science Inventory

    Given the relatively high cost of mapping impervious surfaces at regional scales, substantial effort is being expended in the development of moderate-resolution, satellite-based methods for estimating impervious surface area (ISA). To rigorously assess the accuracy of these data ...

  11. Vectorial mapping of noncollinear antiferromagnetic structure of semiconducting FeSe surface with spin-polarized scanning tunneling microscopy

    SciTech Connect

    Zhang, K. F.; Yang, Fang; Song, Y. R.; Zhang, Xiaole; Chen, Xianfeng; Liu, Canhua; Qian, Dong; Gao, C. L. Jia, Jin-Feng; Luo, Weidong

    2016-02-08

    Antiferromagnetic semiconductors gain increasing interest due to their possible application in spintronics. Using spin polarized scanning tunneling microscopy operating in a vector field, we mapped the noncollinear antiferromagnetic spin structure of a semiconducting hexagonal FeSe surface on the atomic scale. The surface possesses an in-plane compensated Néel structure which is further confirmed by first-principles calculations.

  12. Atmospheric Drivers of Greenland Surface Melt Revealed by Self-Organizing Maps

    NASA Technical Reports Server (NTRS)

    Mioduszewski, J. R.; Rennermalm, A. K.; Hammann, A.; Tedesco, M.; Noble, E. U.; Stroeve, J. C.; Mote, T. L.

    2016-01-01

    Recent acceleration in surface melt on the Greenland ice sheet (GrIS) has occurred concurrently with a rapidly warming Arctic and has been connected to persistent, anomalous atmospheric circulation patterns over Greenland. To identify synoptic setups favoring enhanced GrIS surface melt and their decadal changes, we develop a summer Arctic synoptic climatology by employing self-organizing maps. These are applied to daily 500 hPa geopotential height fields obtained from the Modern Era Retrospective Analysis for Research and Applications reanalysis, 1979-2014. Particular circulation regimes are related to meteorological conditions and GrIS surface melt estimated with outputs from the Modèle Atmosphérique Régional. Our results demonstrate that the largest positive melt anomalies occur in concert with positive height anomalies near Greenland associated with wind, temperature, and humidity patterns indicative of strong meridional transport of heat and moisture. We find an increased frequency in a 500 hPa ridge over Greenland coinciding with a 63% increase in GrIS melt between the 1979-1988 and 2005-2014 periods, with 75.0% of surface melt changes attributed to thermodynamics, 17% to dynamics, and 8.0% to a combination. We also confirm that the 2007-2012 time period has the largest dynamic forcing relative of any period but also demonstrate that increased surface energy fluxes, temperature, and moisture separate from dynamic changes contributed more to melt even during this period. This implies that GrIS surface melt is likely to continue to increase in response to an ever warmer future Arctic, regardless of future atmospheric circulation patterns.

  13. The surface of crystalline basement, Great Valley and Sierra Nevada, California: A digital map database

    USGS Publications Warehouse

    Wentworth, Carl M.; Fisher, G. Reid; Levine, Paia; Jachens, Robert C.

    1995-01-01

    Crystalline basement in central California extends westward from the exposed Sierra Nevada beneath the sedimentary fill of the Great Valley and under the eastern edge of the Coast Ranges at mid-crustal depth. The surface of this basement is defined from three types of control: in the Sierra Nevada from the topography itself, beneath the eastern two thirds of the Great Valley in considerable detail from numerous wells drilled for oil and gas, and beneath the western San Joaquin Valley in less detail from seismic reflection and refraction profiles. Together, these data demonstrate that the surface of crystalline rock is continuous from the exposed rock in the mountains to the top of high-velocity rock buried deep beneath the eastern front of the southern Coast Ranges. This report presents a compilation of data through 1985 that define the surface of this crystalline basement, a contour map of the surface, and the lithology of the basement rock sampled by many of the wells. The compilation was begun as part of the investigation of the 1983 Coalinga earthquake, and was subsequently converted to digital form and extended to the whole of the Great Valley and Sierra Nevada. The main purpose was to explore and document the shape and continuity of the basement surface and to determine the relation of the surface to the tectonic wedge hypothesis (Wentworth and others, 1984; Wentworth and Zoback, 1989). Available basement samples from wells - principally the thin-section collection of May and Hewitt (1948) preserved by the California Academy of Sciences - were also reexamined by cooperating petrologists in an effort to distinguish wells that bottomed in ophiolitic rocks.

  14. A next generation altimeter for mapping the sea surface height variability: opportunities and challenges

    NASA Astrophysics Data System (ADS)

    Fu, Lee-Lueng; Morrow, Rosemary

    2016-07-01

    The global observations of the sea surface height (SSH) have revolutionized oceanography since the beginning of precision radar altimetry in the early 1990s. For the first time we have continuous records of SSH with spatial and temporal sampling for detecting the global mean sea level rise, the waxing and waning of El Niño, and the ocean circulation from gyres to ocean eddies. The limit of spatial resolution of the present constellation of radar altimeters in mapping SSH variability is approaching 100 km (in wavelength) with 3 or more simultaneous altimetric satellites in orbit. At scales shorter than 100 km, the circulation contains substantial amount of kinetic energy in currents, eddies and fronts that are responsible for the stirring and mixing of the ocean, especially from the vertical exchange of the upper ocean with the deep. A mission currently in development will use the technique of radar interferometry for making high-resolution measurement of the height of water over the ocean as well as on land. It is called Surface Water and Ocean Topography (SWOT), which is a joint mission of US NASA and French CNES, with contributions from Canada and UK. SWOT promises the detection of SSH at scales approaching 15 km, depending on the sea state. SWOT will make SSH measurement over a swath of 120 km with a nadir gap of 20 km in a 21-day repeat orbit. A conventional radar altimeter will provide measurement along the nadir. This is an exploratory mission with applications in oceanography and hydrology. The increased spatial resolution offers an opportunity to study ocean surface processes to address important questions about the ocean circulation. However, the limited temporal sampling poses challenges to map the evolution of the ocean variability that changes rapidly at the small scales. The measurement technique and the development of the mission will be presented with emphasis on its science program with outlook on the opportunities and challenges.

  15. Revised potentiometric-surface map, Yucca Mountain and vicinity, Nevada; Water-resources investigations report 93-4000

    SciTech Connect

    Ervin, E.M.; Luckey, R.R.; Burkhardt, D.J.

    1994-05-01

    This report presents a revised potentiometric-surface map based mainly on the 1988 average water levels at Yucca Mountain and the nearby vicinity extending from Crater Flat to Jackass Flats. Discussion includes an explanation of the revised potentiometric-surface map, an examination of yearly trends in the water levels, and adjustments for temperature and density effects in the deeper wells. Report scope focuses on the potentiometric surface of the uppermost saturated zone in the Tertiary volcanic rocks at Yucca Mountain. Some information, related to the underlying Paleozoic carbonate aquifer, pertinent to the volcanic flow system, is presented.

  16. Vertical and lateral force mapping on the Si(111)-(7×7) surface by dynamic force microscopy

    NASA Astrophysics Data System (ADS)

    Sugimoto, Yoshiaki; Namikawa, Takashi; Miki, Koutaro; Abe, Masayuki; Morita, Seizo

    2008-05-01

    The topographic image of dynamic force microscopy (DFM) keeping the frequency shift (Δfz) constant at tiny cantilever oscillation amplitudes corresponds to the constant-vertical force (Fz) gradient surface, while the interpretation becomes complicated at larger oscillation amplitudes. We discuss how Fz and the potential energy (U) act on the tip during DFM topographic scan at various cantilever oscillation amplitudes by measuring the Δfz map on the Si(111)-(7×7) surface at room temperature. The Δfz map is numerically converted into Fz and U maps. DFM topographic curves at various cantilever oscillation amplitudes are numerically derived by using the experimentally obtained Fz map. In addition, we discuss how the lateral force (Fx) acts on the tip at various tip-surface distances on various surface sites by an Fx map converted from a U map. The positions at which Fx becomes zero are identified as U minimum sites, such as the top of adatom sites, and U maximum sites (equilibrium positions of Fx ), such as the center positions among three center adatoms. The tip deviated from these sites is then laterally attracted toward the U minimum sites. It is also demonstrated that lateral force microscopy performed at 1Å cantilever oscillation enables direct measurement of the lateral force gradient by numerically deriving the frequency shift (Δfx) caused by Fx .

  17. Mars Surface Mineralogic Diversity and Mineral Mixtures Mapping Using CRISM Data and the Tetracorder Spectral Mapping System

    NASA Astrophysics Data System (ADS)

    Clark, R. N.; Swayze, G. A.; Murchie, S. L.; Seelos, F. P., IV; Seelos, K. D.; Viviano-Beck, C.; Bishop, J. L.

    2015-12-01

    The search for minerals and other materials from the wealth of imaging spectroscopy data being returned from Mars poses a formidable task. Most recent mapping has required human intensive massaging/filtering of image cubes and mapping by parameters. The new CRISM Map-projected Targeted Reduced Data Record (MTRDR) image cubes enable a new level of sophistication in detection and mapping of materials. We use a new version of Tetracorder that has a more sophisticated expert system for the identification and mapping of materials in CRISM data, including curved continuum removal that permits more robust detection of weak spectral features embedded in larger features. The use of spectral feature fitting algorithms and curved continua enable subtle changes in mineralogy to be detected, including weak hydroxyl and carbonate features in the presence of strong >2 micron pyroxene absorptions, and organics and carbonates in the presence of the strong curvature from the 3-micron water band so prevalent on Mars. In mapping numerous CRISM scenes to date we find interesting mineralogic diversity expressed in the position and shape of the 1.9-micron water absorption, ranging from ~1.91 microns in many clays to ~1.93 microns in sulfates and may be an indicator of these minerals when the OH features are too weak to observe. All scenes mapped so far show the presence of the 1.9-micron water in various band positions. Another mineral found to be extensive is prehnite and mixtures of prehnite with chlorite and/or serpentine. Prehnite, Ca2Al(AlSi3O10)(OH)2, is a secondary or hydrothermal mineral in veins and cavities in mafic volcanic rocks and a product of low-grade metamorphism. Other minerals mapped include the clino-orthopyroxene series, clay minerals, sulfates, olivine, magnetite, hematite and goethite grain sizes, other Fe2+ and Fe3+ minerals, and H2O and CO2 ice. These diverse mineralogies could guide present and future landing missions to geologically interesting areas.

  18. Evaluation Model for Pavement Surface Distress on 3d Point Clouds from Mobile Mapping System

    NASA Astrophysics Data System (ADS)

    Aoki, K.; Yamamoto, K.; Shimamura, H.

    2012-07-01

    This paper proposes a methodology to evaluate the pavement surface distress for maintenance planning of road pavement using 3D point clouds from Mobile Mapping System (MMS). The issue on maintenance planning of road pavement requires scheduled rehabilitation activities for damaged pavement sections to keep high level of services. The importance of this performance-based infrastructure asset management on actual inspection data is globally recognized. Inspection methodology of road pavement surface, a semi-automatic measurement system utilizing inspection vehicles for measuring surface deterioration indexes, such as cracking, rutting and IRI, have already been introduced and capable of continuously archiving the pavement performance data. However, any scheduled inspection using automatic measurement vehicle needs much cost according to the instruments' specification or inspection interval. Therefore, implementation of road maintenance work, especially for the local government, is difficult considering costeffectiveness. Based on this background, in this research, the methodologies for a simplified evaluation for pavement surface and assessment of damaged pavement section are proposed using 3D point clouds data to build urban 3D modelling. The simplified evaluation results of road surface were able to provide useful information for road administrator to find out the pavement section for a detailed examination and for an immediate repair work. In particular, the regularity of enumeration of 3D point clouds was evaluated using Chow-test and F-test model by extracting the section where the structural change of a coordinate value was remarkably achieved. Finally, the validity of the current methodology was investigated by conducting a case study dealing with the actual inspection data of the local roads.

  19. Mapping the near-surface electrical conductivity with DEMETER satellite VLF data

    NASA Astrophysics Data System (ADS)

    Leye, P.; Tarits, P.

    2012-12-01

    Electromagnetic methods in geophysics are useful tools in hydrology and environmental studies. They provide maps of the near-surface electrical conductivity with depth. The well known Very Low Frequency (VLF) sounding technique is revisited in this study with the emphasis on applications using the anthropogenic VLF wave recorded by satellites. The source is the electromagnetic (EM) signal transmitted in the 15 - 20 kHz frequency band by several VLF station located on the Earth surface. The micro-satellite DEMETER (CNES - France) measured the electric and magnetic fields in this frequency range at 700 km altitude. The ICE \\citep{Berthelier2006456} and IMSC \\citep{Parrot2006441} sensors on-board the aircraft measured respectively and simultaneously the electric (E) and magnetic (B) component of the EM field. Theoretical calculations \\citep{Wait2} have shown how this field depended on near-surface properties for earth surface and aircraft measurements. Here we investigate for the first time the modeling of these VLF waves measured at satellite altitudes taking into account the effect of the ionosphere. We show that the theoretical EM field is consistent with the measurements by the satellite. The results suggest that the DEMETER data may be used to study the Earth near-surface properties. We study the relationship between the EM impedance (the ratio between the tangential component E and B EM field) and the Earth conductivity. The ratio has the advantage of being independent on the antenna's current moment. We compare theoretical and observed impedances as a function of the Earth conductivity.

  20. Mapping a near surface variable geologic regime using an integrated geophysical approach

    SciTech Connect

    Rogers, N.T.; Sandberg, S.K.; Miller, P.; Powell, G.

    1997-10-01

    An integrated geophysical approach involving seismic, electromagnetic, and electrical methods was employed to map fluvial, colluvial and bedrock geology, to delineate bedrock channels, and to determine fracture and joint orientations that may influence migration of petroleum hydrocarbons at the Glenrock Oil Seep. Both P (primary)-wave and S (shear)-wave seismic refraction techniques were used to map the bedrock surface topography, bedrock minima, stratigraphic boundaries, and possible structure. S-wave data were preferred because of better vertical resolution due to the combination of slower velocities and lower frequency wave train. Azimuthal resistivity/EP (induced polarization) and azimuthal electromagnetics were used to determine fracture orientations and groundwater flow directions. Terrain conductivity was used to map the fluvial sedimentary sequences (e.g., paleochannel and overbank deposits) in the North Platte River floodplain. Conductivity measurements were also used to estimate bedrock depth and to assist in the placement and recording parameters of the azimuthal soundings. The geophysical investigation indicated that groundwater flow pathways were controlled by the fluvial paleochannels and bedrock erosional features. Primary groundwater flow direction in the bedrock and colluvial sediments was determined from the azimuthal measurements and confirmed by drilling to be N20-40W along the measured strike of the bedrock and joint orientations. Joint/fracture orientations were measured at N20-40W and N10-30E from the azimuthal data and confirmed from measurements at a bedrock outcrop south of the site. The bedrock has an apparent N10E anisotropy in the seismic velocity profiles on the old refinery property that closely match that of measured joint/fracture orientations and may have a minor effect on groundwater flow.

  1. Map showing the potentiometric surface of the Magothy Aquifer in southern Maryland, September 1981

    USGS Publications Warehouse

    Mack, F.K.; Wheeler, J.C.; Curtin, S.E.

    1982-01-01

    The map is based on measurements from a network of 83 observation wells cased to the Magothy aquifer. Highest levels of the potentiometric surface, 59 to 60 feet above sea level, were measured near the outcrop-subcrop of the aquifer in topographically high areas of Anne Arundel and Prince Georges Counties. The surface slopes to the southeast to above sea level along much of the western shore of Chesapeake Bay. Three separate, distinct, and extensive cones of depression have developed in the potentiometric surface around the well fields of the city of Annapolis-Broadneck Peninsula area, town of Waldorf, and Chalk Point. Several square miles of each cone are below sea level, and, in some areas at Chalk Point and Waldorf, the cone is 40 to 50 feet below sea level. The network of wells was developed as part of the cooperative program between the U.S. Geological Survey, the Maryland Geological Survey, and the Maryland Energy and Coastal Zone Administration. (USGS)

  2. An analytic mapping of oligomer potential energy surfaces to an effective Frenkel model.

    PubMed

    Binder, Robert; Römer, Sarah; Wahl, Jan; Burghardt, Irene

    2014-07-07

    While the use of Frenkel-type models for semiconducting polymer assemblies and related molecular aggregates is well established, the direct parametrization of such models based on electronic structure data is attempted less frequently. In this work, we develop a systematic mapping procedure which is adapted to J-type and H-type homo-aggregate systems. The procedure is based upon the analytic solution of an inverse eigenvalue problem for an effective Frenkel Hamiltonian with nearest-neighbor couplings. Vibronic interactions are included for both site-local and site-correlated modes. For illustration, an application is presented to the excited-state ab initio potential energy surfaces (PESs) of an oligothiophene octamer. The procedure performs a pointwise mapping of the PESs of oligomers of arbitrary chain length n, provided that the electronic ground state and any two of the n lowest adiabatic states of the excitonic manifold of interest are known. These three states are reproduced exactly by the procedure while the remaining n - 2 states of the excitonic manifold can be predicted. Explicit conditions are derived permitting to verify whether a given data set is compatible with the effective Frenkel model under study.

  3. An analytic mapping of oligomer potential energy surfaces to an effective Frenkel model

    SciTech Connect

    Binder, Robert; Römer, Sarah E-mail: burghardt@chemie.uni-frankfurt.de; Wahl, Jan; Burghardt, Irene E-mail: burghardt@chemie.uni-frankfurt.de

    2014-07-07

    While the use of Frenkel-type models for semiconducting polymer assemblies and related molecular aggregates is well established, the direct parametrization of such models based on electronic structure data is attempted less frequently. In this work, we develop a systematic mapping procedure which is adapted to J-type and H-type homo-aggregate systems. The procedure is based upon the analytic solution of an inverse eigenvalue problem for an effective Frenkel Hamiltonian with nearest-neighbor couplings. Vibronic interactions are included for both site-local and site-correlated modes. For illustration, an application is presented to the excited-state ab initio potential energy surfaces (PESs) of an oligothiophene octamer. The procedure performs a pointwise mapping of the PESs of oligomers of arbitrary chain length n, provided that the electronic ground state and any two of the n lowest adiabatic states of the excitonic manifold of interest are known. These three states are reproduced exactly by the procedure while the remaining n − 2 states of the excitonic manifold can be predicted. Explicit conditions are derived permitting to verify whether a given data set is compatible with the effective Frenkel model under study.

  4. A Global Map of Coherent M2 Internal Tide Surface Elevations

    NASA Astrophysics Data System (ADS)

    Ray, R. D.; Zaron, E. D.

    2014-12-01

    Satellite altimetry reveals small surface waves, with elevations of order 1 cm or smaller, associated with internal tides in the deep ocean. The global satellite data provide an unprecedented picture of such waves, potentially yielding much information about the ocean interior. Accurate knowledge of these waves is also needed for de-tiding altimetry in certain sensitive applications, including the future SWOT mission. Several approaches have been initiated recently to map these tiny waves, usually with some reliance on hydrographic information (e.g., recent work by Dushaw et al., 2011). Here we explore the feasibility of a purely empirical approach which avoids assumptions about stratification or modal wavelengths. A global elevation map is constructed based on tidal analysis of Topex/Poseidon, Jason, ERS-2, Envisat and GFO data. Small (order 5 mm) residuals, with wavelengths much longer than the baroclinic tide, appear unless now-standard along-track high-pass filters are applied, but filtering is shown to cause serious loss of information for east-west propagating waves (given typical track patterns). The technique is probably infeasible for S2 because of Envisat's and ERS's sun-synchronous orbits. Independent data from Cryosat-2 is used to validate the results. Applying our internal-tide 'correction' to Cryosat-2 data confirms a small reduction in variance in expected locations of significant internal tides.

  5. Validation of Spaceborne Radar Surface Water Mapping with Optical sUAS Images

    NASA Astrophysics Data System (ADS)

    Li-Chee-Ming, J.; Murnaghan, K.; Sherman, D.; Poncos, V.; Brisco, B.; Armenakis, C.

    2015-08-01

    The Canada Centre for Remote Sensing (CCRS) has over 40 years of experience with airborne and spaceborne sensors and is now starting to use small Unmanned Aerial Systems (sUAS) to validate products from large coverage area sensors and create new methodologies for very high resolution products. Wetlands have several functions including water storage and retention which can reduce flooding and provide continuous flow for hydroelectric generation and irrigation for agriculture. Synthetic Aperture Radar is well suited as a tool for monitoring surface water by supplying acquisitions irrespective of cloud cover or time of day. Wetlands can be subdivided into three classes: open water, flooded vegetation and upland which can vary seasonally with time and water level changes. RADARSAT-2 data from the Wide-Ultra Fine, Spotlight and Fine Quad-Pol modes has been used to map the open water in the Peace-Athabasca Delta, Alberta using intensity thresholding. We also use spotlight modes for higher resolution and the fully polarimetric mode (FQ) for polarimetric decomposition. Validation of these products will be done using a low altitude flying sUAS to generate optical georeferenced images. This project provides methodologies which could be used for flood mapping as well as ecological monitoring.

  6. Salt Repository Project site study plan for surface geological mapping: Revision 1, December 22, 1987

    SciTech Connect

    Not Available

    1988-03-01

    This site study plan describes the Surface Geological Mapping field activities to be conducted during early stages of Site Characterization for the Deaf Smith County Site, Texas. The field program has been designed to provide data useful in addressing information and design data needs resulting from Federal/State/local regulatory requirements and repository program requirements. Air and ground surveys and an extensive literature search will be conducted to map areas within and hear proposed nuclear waste repository site in the Deaf Smith County. Findings from this study may identify additional areas requiring further investigation, for which a new site study plan will be prepared. The Salt Repository Project (SRP) Networks specify the schedule under which the program will operate. The Technical and Field Services Contractor (TFSC) is responsible for conducting the field program. Data will be handled and reported in accordance with established SRP procedures. A quality assurance program will be utilized to assure that activities affecting quality are performed correctly and the appropriate documentation is maintained. 27 refs., 13 figs., 5 tabs.

  7. Mapping surface energy balance components by combining landsat thematic mapper and ground-based meteorological data

    USGS Publications Warehouse

    Moran, M.S.; Jackson, R. D.; Raymond, L.H.; Gay, L.W.; Slater, P.N.

    1989-01-01

    Surface energy balance components were evaluated by combining satellite-based spectral data with on-site measurements of solar irradiance, air temperature, wind speed, and vapor pressure. Maps of latent heat flux density (??E) and net radiant flux density (Rn) were produced using Landsat Thematic Mapper (TM) data for three dates: 23 July 1985, 5 April 1986, and 24 June 1986. On each date, a Bowen-ratio apparatus, located in a vegetated field, was used to measure ??E and Rn at a point within the field. Estimates of ??E and Rn were also obtained using radiometers aboard an aircraft flown at 150 m above ground level. The TM-based estimates differed from the Bowen-ratio and aircraft-based estimates by less than 12 % over mature fields of cotton, wheat, and alfalfa, where ??E and Rn ranged from 400 to 700 Wm-2. ?? 1989.

  8. Field studies in support of Nimbus-E surface composition mapping radiometer

    NASA Technical Reports Server (NTRS)

    Lyon, R. J. P.; Green, A. A.

    1973-01-01

    If the outputs of the two channels are spacially registered and combined to generate a third variable which reflects the differences between the two outputs, then this variable can then be redisplayed in image form and its magnitude should be relatable to the silica content of the rocks imaged. Two methods were proposed for generating this third variable, the first is to take the difference in apparent temperature between the two channels and the second is to ratio the voltage outputs of the two channels. The responses of the two channel high resolution surface composition mapping radiometer and the thermal channels of the MSDS scanner were calculated from data recorded with the NASA IR pallet and simulate the output of these systems had they been flying over the same targets as the IR pallet.

  9. Mapping cellular hierarchy by single cell analysis of the cell surface repertoire

    PubMed Central

    Guo, Guoji; Luc, Sidinh; Marco, Eugenio; Lin, Ta-Wei; Peng, Cong; Kerenyi, Marc A.; Beyaz, Semir; Kim, Woojin; Xu, Jian; Das, Partha Pratim; Neff, Tobias; Zou, Keyong; Yuan, Guo-Cheng; Orkin, Stuart H.

    2013-01-01

    SUMMARY Stem cell differentiation pathways are most often studied at the population level, whereas critical decisions are executed at the level of single cells. We have established a highly multiplexed, quantitative PCR assay to profile in an unbiased manner a panel of all commonly used cell surface markers (280 genes) from individual cells. With this method we analyzed over 1500 single cells throughout the mouse hematopoietic system, and illustrate its utility for revealing important biological insights. The comprehensive single cell dataset permits mapping of the mouse hematopoietic stem cell (HSC) differentiation hierarchy by computational lineage progression analysis. Further profiling of 180 intracellular regulators enabled construction of a genetic network to assign the earliest differentiation event during hematopoietic lineage specification. Analysis of acute myeloid leukemia elicited by MLL-AF9 uncovered a distinct cellular hierarchy containing two independent self-renewing lineages with different clonal activities. The strategy has broad applicability in other cellular systems. PMID:24035353

  10. Maps showing sedimentary basins, surface thermal maturity, and indications of petroleum in the Central Alaska Province

    USGS Publications Warehouse

    Troutman, Sandra M.; Stanley, Richard G.

    2003-01-01

    This publication includes two maps (at 1:2,500,000 scale) and a pamphlet that describe sedimentary basins, surface thermal maturity, and 95 reported occurrences of petroleum in natural seeps, wells, and rock outcrops in central Alaska. No commercial petroleum production has been obtained from central Alaska, in contrast to the prolific deposits of oil and gas that have been found and developed in northern Alaska and the Cook Inlet region. Nevertheless, confirmed indications of petroleum in central Alaska include (1) natural seeps of methane gas on the Yukon Delta; (2) occurrences of methane gas in wells in the Bethel, Kotzebue, Nenana, Northway, and Yukon Flats basins; (3) oil and methane gas in seeps and wells in Norton Sound; (4) small quantities of liquid and solid hydrocarbons associated with mercury ore in the Kuskokwim Mountains; (5) oil shale and numerous occurrences of bitumen in the Kandik area; and (6) tasmanite, a form of oil shale, in the uplands north of Yukon Flats.

  11. Detailed mapping of surface units on Mars with HRSC color data

    NASA Astrophysics Data System (ADS)

    Combe, J.-Ph.; Wendt, L.; McCord, T. B.; Neukum, G.

    2008-09-01

    Introduction: Making use of HRSC color data Mapping outcrops of clays, sulfates and ferric oxides are basis information to derive the climatic, tectonic and volcanic evolution of Mars, especially the episodes related to the presence of liquid water. The challenge is to resolve spatially the outcrops and to distinguish these components from the globally-driven deposits like the iron oxide-rich bright red dust and the basaltic dark sands. The High Resolution Stereo Camera (HRSC) onboard Mars-Express has five color filters in the visible and near infrared that are designed for visual interpretation and mapping various surface units [1]. It provides also information on the topography at scale smaller than a pixel (roughness) thanks to the different geometry of observation for each color channel. The HRSC dataset is the only one that combines global coverage, 200 m/pixel spatial resolution or better and filtering colors of light. The present abstract is a work in progress (to be submitted to Planetary and Space Science) that shows the potential and limitations of HRSC color data as visual support and as multispectral images. Various methods are described from the most simple to more complex ones in order to demonstrate how to make use of the spectra, because of the specific steps of processing they require [2-4]. The objective is to broaden the popularity of HRSC color data, as they could be used more widely by the scientific community. Results prove that imaging spectrometry and HRSC color data complement each other for mapping outcrops types. Example regions of interest HRSC is theoretically sensitive to materials with absorption features in the visible and near-infrared up to 1 μm. Therefore, oxide-rich red dust and basalts (pyroxenes) can be mapped, as well as very bright components like water ice [5, 6]. Possible detection of other materials still has to be demonstrated. We first explore regions where unusual mineralogy appears clearly from spectral data. Hematite

  12. ST-T isointegral analysis of exercise stress body surface mapping for identifying ischemic areas in patients with angina pectoris

    SciTech Connect

    Nakajima, T.; Kawakubo, K.; Toda, I.; Mashima, S.; Ohtake, T.; Iio, M.; Sugimoto, T.

    1988-05-01

    ST-T isointegral analysis of body surface mapping was used in an attempt to localize ischemic areas on exercise tests. In 28 patients with angina pectoris and 10 healthy subjects, body surface potential was recorded with 87 leads, and ST isopotential and ST-T isointegral maps were constructed. In all 10 healthy subjects, the basic pattern of the ST-T isointegral map showed no significant change after exercise. In 23 of 28 patients with angina pectoris (82%), alterations in the ST-T isointegral map after exercise were observed. They were divided into four types (anterior, inferoposterior, lateral, and global) according to the distribution of negative values, which were well correlated with the extent of ischemic area determined by thallium myocardial scintigraphy and coronary angiography. The postexercise ST-T isointegral map was normalized after administration of nitroglycerin in four of five patients. In five patients (18%) who did not show abnormalities on the postexercise ST-T isointegral map, the magnitude of maximal ST depression was significantly smaller than that observed in the other 23 patients with angina pectoris (0.14 vs 0.23 mV on the average, p less than 0.05). It was concluded that the exercise test with ST-T isointegral mapping is a new method for noninvasive detection of location and severity of ischemic regions.

  13. Computerized mappings of the cerebral cortex: a multiresolution flattening method and a surface-based coordinate system

    NASA Technical Reports Server (NTRS)

    Drury, H. A.; Van Essen, D. C.; Anderson, C. H.; Lee, C. W.; Coogan, T. A.; Lewis, J. W.

    1996-01-01

    We present a new method for generating two-dimensional maps of the cerebral cortex. Our computerized, two-stage flattening method takes as its input any well-defined representation of a surface within the three-dimensional cortex. The first stage rapidly converts this surface to a topologically correct two-dimensional map, without regard for the amount of distortion introduced. The second stage reduces distortions using a multiresolution strategy that makes gross shape changes on a coarsely sampled map and further shape refinements on progressively finer resolution maps. We demonstrate the utility of this approach by creating flat maps of the entire cerebral cortex in the macaque monkey and by displaying various types of experimental data on such maps. We also introduce a surface-based coordinate system that has advantages over conventional stereotaxic coordinates and is relevant to studies of cortical organization in humans as well as non-human primates. Together, these methods provide an improved basis for quantitative studies of individual variability in cortical organization.

  14. Soil depth mapping using seismic surface waves: Evaluation on eroded loess covered hillslopes

    NASA Astrophysics Data System (ADS)

    Bernardie, Severine; Samyn, Kevin; Cerdan, Olivier; Grandjean, Gilles

    2010-05-01

    The purposes of the multidisciplinary DIGISOIL project are the integration and improvement of in situ and proximal technologies for the assessment of soil properties and soil degradation indicators. Foreseen developments concern sensor technologies, data processing and their integration to applications of (digital) soil mapping (DSM). Among available techniques, the seismic one is, in this study, particularly tested for characterising soil vulnerability to erosion. The spectral analysis of surface waves (SASW) method is an in situ seismic technique used for evaluation of the stiffnesses (G) and associated depth in layered systems. A profile of Rayleigh wave velocity versus frequency, i.e., the dispersion curve, is calculated from each recorded seismogram before to be inverted to obtain the vertical profile of shear wave velocity Vs. Then, the soil stiffness can easily be calculated from the shear velocity if the material density is estimated, and the soil stiffness as a function of depth can be obtained. This last information can be a good indicator to identify the soil bedrock limit. SASW measurements adapted to soil characterisation is proposed in the DIGISOIL project, as it produces in an easy and quick way a 2D map of the soil. This system was tested for the digital mapping of the depth of loamy material in a catchment of the European loess belt. The validation of this methodology has been performed with the realisation of several acquisitions along the seismic profiles: - Several boreholes were drilled until the bedrock, permitting to get the geological features of the soil and the depth of the bedrock; - Several laboratory measurements of various parameters were done on samples taken from the boreholes at various depths, such as dry density, solid density, and water content; - Dynamic penetration tests were also conducted along the seismic profile, until the bedrock is attained. Some empirical correlations between the parameters measured with laboratory tests

  15. Global mapping of the elemental composition of the Moon surface with SELENE GRS.

    NASA Astrophysics Data System (ADS)

    D'Uston, C.; Hasebe, N.

    2007-08-01

    .) over the entire lunar surface. The results will be highly accurate and will provide important new clues with respect to understanding the origin and evolution of the moon. The observations will contribute to lunar resource exploration, especially for water existence. Water is very essential for human activity in a lunar platform in the future and local supply of water is necessary for the sake of cost performance. GRS can identify gamma rays from hydrogen and can map hydrogen.

  16. Mapping and characterization of non-polar permanent shadows on the lunar surface

    NASA Astrophysics Data System (ADS)

    McGovern, J. Andrew; Bussey, D. Benjamin; Greenhagen, Benjamin T.; Paige, David A.; Cahill, Joshua T. S.; Spudis, Paul D.

    2013-03-01

    We present the first globally complete inventory of permanent shadows on the lunar surface that are detectable with the current global instrument datasets, including discovery of regions with persistent shadows over geologic time periods as close to the equator as ±58° of latitude. These results were obtained through application of a ray tracing technique to the latest global topographic datasets from the Lunar Reconnaissance Orbiter. Our analysis reveals that 13,361 km2 of surface in the northern hemisphere and 17,698 km2 in the southern hemisphere are permanently shadowed. We present maps showing the locations of all the permanent shadows detectable using these datasets then turn our focus toward the permanent shadows farthest from the poles. Each permanent shadow on the equator side of ±65° of latitude is shown in detail. Surface brightness temperature data derived from the Diviner mid-infrared radiometer on board the Lunar Reconnaissance Orbiter have been analyzed for four of these locations and found to have mid-day temperatures 75-120 K less than nearby comparison locations that experience direct daytime illumination. In some cases the permanently shadowed locations have nighttime temperatures 10-25 K lower than surroundings. The temperature results support our finding that these non-polar craters are permanently shadowed. The surface brightness temperature results also raise interesting questions about their ability to cold trap volatiles. Discovery of these non-polar permanently shadowed regions increases possible locations of water resources and high priority exploration targets on the Moon.

  17. Guided asteroid deflection by kinetic impact: Mapping keyholes to an asteroid's surface

    NASA Astrophysics Data System (ADS)

    Chesley, S.; Farnocchia, D.

    2014-07-01

    range from around 1 for a porous, compressible body producing negligible ejecta, to 2 when the ejecta momentum matches the spacecraft momentum, and as high as 5--10 for rocky bodies that produce large, high-velocity ejecta fragments. If the impactor hits the centerpoint of a spherical asteroid the momentum of the escaping ejecta directly adds to the momentum of the impacting asteroid, but if the impact is oblique then the ejecta and spacecraft momenta are added to the asteroid in vector sum. This suggests the possibility that for a given intercept trajectory the asteroid deflection could include guidance by targeting an oblique impact that could steer the asteroid Δ V to a more optimal direction that is different from the relative velocity direction of the spacecraft. An oblique impact decreases the net Δ V magnitude, and yet could significantly increase the net deflection at the time of the threatening Earth encounter. We use asteroid (101955) Bennu, which is the target of the OSIRIS-REx asteroid sample return mission and which has a series of potential Earth impacts in the years from 2175--2196, as an example to demonstrate the effectiveness of the oblique impact. These future potential impacts will occur if the asteroid passes through one of a series of keyholes when the asteroid passes the Earth at roughly the lunar distance from the Earth in 2135. To study the Bennu deflection problem we simulate a hypervelocity spacecraft impact on Bennu in March 2021, after the OSIRIS-REx mission is complete. In our example, the spacecraft arrives from approximately the sunward direction, and targeting ahead or behind the center of the asteroid allows non-negligible transverse accelerations for modest values of β. A given impact location on the asteroid surface yields a given Δ V vector, and our approach starts by mapping the net Δ V components on the surface for an assumed value of β. Knowing the mapping from impact location to Δ V and also the mapping from Δ V to the

  18. Mathematical modeling of temperature mapping over skin surface and its implementation in thermal disease diagnostics.

    PubMed

    Deng, Zhong-Shan; Liu, Jing

    2004-09-01

    In non-invasive thermal diagnostics, accurate correlations between the thermal image on skin surface and interior human pathophysiology are often desired, which require general solutions for the bioheat equation. In this study, the Monte Carlo method was implemented to solve the transient three-dimensional bio-heat transfer problem with non-linear boundary conditions (simultaneously with convection, radiation and evaporation) and space-dependent thermal physiological parameters. Detailed computations indicated that the thermal states of biological bodies, reflecting physiological conditions, could be correlated to the temperature or heat flux mapping recorded at the skin surface. The effect of the skin emissivity and humidity, the convective heat transfer coefficient, the relative humidity and temperature of the surrounding air, the metabolic rate and blood perfusion rate in the tumor, and the tumor size and number on the sensitivity of thermography are comprehensively investigated. Moreover, several thermal criteria for disease diagnostic were proposed based on statistical principles. Implementations of this study for the clinical thermal diagnostics are discussed.

  19. Mapping the tRNA binding site on the surface of human DNMT2 methyltransferase.

    PubMed

    Jurkowski, Tomasz P; Shanmugam, Raghuvaran; Helm, Mark; Jeltsch, Albert

    2012-06-05

    The DNMT2 enzyme methylates tRNA-Asp at position C38. Because there is no tRNA-Dnmt2 cocrystal structure available, we have mapped the tRNA binding site of DNMT2 by systematically mutating surface-exposed lysine and arginine residues to alanine and studying the tRNA methylation activity and binding of the corresponding variants. After mutating 20 lysine and arginine residues, we identified eight of them that caused large (>4-fold) decreases in catalytic activity. These residues cluster within and next to a surface cleft in the protein, which is large enough to accommodate the tRNA anticodon loop and stem. This cleft is located next to the binding pocket for the cofactor S-adenosyl-L-methionine, and the catalytic residues of DNMT2 are positioned at its walls or bottom. Many of the variants with strongly reduced catalytic activity showed only a weak loss of tRNA binding or even bound better to tRNA than wild-type DNMT2, which suggests that the enzyme induces some conformational changes in the tRNA in the transition state of the methyl group transfer reaction. Manual placement of tRNA into the structure suggests that DNMT2 mainly interacts with the anticodon stem and loop.

  20. Surface mapping of field-induced piezoelectric strain at elevated temperature employing full-field interferometry.

    PubMed

    Stevenson, Tim; Quast, Tatjana; Bartl, Guido; Schmitz-Kempen, Thorsten; Weaver, Paul M

    2015-01-01

    Piezoelectric actuators and sensors are widely used for flow control valves, including diesel injectors, ultrasound generation, optical positioning, printing, pumps, and locks. Degradation and failure of material and electrical properties at high temperature typically limits these applications to operating temperatures below 200°C, based on the ubiquitous Pb(Zr,Ti)O3 ceramic. There are, however, many applications in sectors such as automotive, aerospace, energy and process control, and oil and gas, where the ability to operate at higher temperatures would open up new markets for piezoelectric actuation. Presented here is a review of recent progress and initial results toward a European effort to develop measurement techniques to characterize high-temperature materials. Full-field, multi-wavelength absolute length interferometry has, for the first time, been used to map the electric-field-induced piezoelectric strain across the surface of a PZT ceramic. The recorded variation as a function of temperature has been evaluated against a newly developed commercial single-beam system. Conventional interferometry allows measurement of the converse piezoelectric effect with high precision and resolution, but is often limited to a single point, average measurement and to limited sample environments because of optical aberrations in varying atmospheres. Here, the full-field technique allows the entire surface to be analyzed for strain and, in a bespoke sample chamber, for elevated temperatures.

  1. Mapping of upper electronic reaction surfaces by tuned laser photolysis and by absorption and emission spectroscopies

    SciTech Connect

    Morgan, M.A.

    1989-07-01

    Potential energy surfaces for photorotamerization of two intramolecularly hydrogen-bonded molecules, o-hydroxybenzaldehyde (OHBA) and methyl salicylate (MS), isolated in cryogenic matrices have been spectroscopically mapped. In addition, the external heavy atom effect of krypton and xenon matrices on the coupling between the S{sub 1} and T{sub 1} surfaces of 4-(dimethylamino)benzonitrile has been examined. Heavy atom matrices are known to increase rates of spin-forbidden processes. The phosphorescence intensity of DMABN increases in krypton and xenon matrices, while the fluorescence intensity, and phosphorescence and fluorescence lifetimes, decrease. These effects are interpreted in terms of a model in which the phosphorescence rate constant increases 300-fold in xenon compared to argon, while the rate constants for intersystem crossing and nonradiative relaxation from the triplet state increase by factors of less than 5. Lifetime measurements in argon matrices doped with heavy atoms indicate that even one heavy atom neighbor has a significant effect on both singlet and triplet lifetimes. 78 refs., 35 figs., 15 tabs.

  2. Raman mapping analysis for removal of surface secondary phases of CZTS films using chemical etching

    NASA Astrophysics Data System (ADS)

    Wei, Zhengfei; Newman, Michael J.; Tsoi, Wing C.; Watson, Trystan M.

    2016-09-01

    Raman spectroscopy has been widely used as a non-destructive surface characterization method for the Cu2ZnSnS4 (CZTS) thin films. Secondary phases, which often co-exist with CZTS, are detrimental to the device performance. In this work, removal of the secondary phases using sodium sulfide (Na2S) aqueous solution etching in various time durations was investigated. Raman scattering mapping provides a direct visualization of phase distribution in CZTS-based materials on a relatively large scale (1 mm × 10 mm). Both as-grown and etched CZTS absorber layers were examined by Raman spectroscopy with a 532 nm excitation laser light in the range of 50-500 cm-1. A clear reduction of the secondary phases (mainly SnS) at the surface after etching was confirmed by Raman spectroscopy and scanning electron microscopy. Room temperature photoluminescence (PL) reveals a pronounced correlation between the amount of secondary phases and photoluminescence peak position. The PL spectra of the regions with more Sn-rich secondary phases show clearly a shift to high wavelength of the peak position, in comparison with regions with less Sn-rich secondary phases. These observed PL changes could be due to Sn-rich defects which may cause recombination processes.

  3. Euro-Maps 3D- A Transnational, High-Resolution Digital Surface Model For Europe

    NASA Astrophysics Data System (ADS)

    Uttenthaler, A.; Barner, F.; Hass, T.; Makiola, J.; d'Angelo, P.; Reinartz, P.; Carl, S.; Steiner, K.

    2013-12-01

    Euro-Maps 3D is a homogeneous 5 m spaced digital surface model (DSM) semi-automatically derived by Euromap from 2.5 m in-flight stereo data provided by the Indian IRS-P5 Cartosat-1 satellite. This new and innovative product has been developed in close co- operation with the Remote Sensing Technology Institute (IMF) of the German Aerospace Center (DLR) and is being jointly exploited. The very detailed and accurate representation of the surface is achieved by using a sophisticated and well adapted algorithm implemented on the basis of the Semi-Global Matching approach. In addition, the final product includes detailed flanking information consisting of several pixel-based quality and traceability layers also including an ortho layer. The product is believed to provide maximum accuracy and transparency. The DSM product meets and exceeds HRE80 qualification standards. The DSM product will be made available transnational in a homogeneous quality for most parts of Europe, North Africa and Turkey by Euromap step-by-step. Other areas around the world are processed on demand.

  4. Toward mapping surface deformation in three dimensions using InSAR

    USGS Publications Warehouse

    Wright, Tim J.; Parsons, Barry E.; Lu, Zhong

    2004-01-01

    One of the limitations of deformation measurements made with interferometric synthetic aperture radar (InSAR) is that an interferogram only measures one component of the surface deformation-in the satellite's line of sight. We investigate strategies for mapping surface deformation in three dimensions by using multiple interferograms, with different imaging geometries. Geometries for both current and future missions are evaluated, and their abilities to resolve the displacement vector arc compared. The north component is always the most difficult to determine using data from near-polar orbiting satellites. However, a satellite with an inclination of about 60??/120?? would enable all three components to be well resolved. We attempt to resolve the 3D displacements for the 23 October 2002 Nenana Mountain (Alaska) Earthquake. The north component's error is much larger than the signal, but proxies for eastward and vertical motion can be determined if the north component is assumed negligible. Inversions of hypothetical coseismic interferograms demonstrate that earthquake model parameters can be well recovered from two interferograms, acquired on ascending and descending tracks. Copyright 2004 by the American Geophysical Union.

  5. Point contact tunneling spectroscopy apparatus for large scale mapping of surface superconducting properties

    SciTech Connect

    Groll, Nickolas; Pellin, Michael J.; Zasadzinksi, John F.; Proslier, Thomas

    2015-09-15

    We describe the design and testing of a point contact tunneling spectroscopy device that can measure material surface superconducting properties (i.e., the superconducting gap Δ and the critical temperature T{sub C}) and density of states over large surface areas with size up to mm{sup 2}. The tip lateral (X,Y) motion, mounted on a (X,Y,Z) piezo-stage, was calibrated on a patterned substrate consisting of Nb lines sputtered on a gold film using both normal (Al) and superconducting (PbSn) tips at 1.5 K. The tip vertical (Z) motion control enables some adjustment of the tip-sample junction resistance that can be measured over 7 orders of magnitudes from a quasi-ohmic regime (few hundred Ω) to the tunnel regime (from tens of kΩ up to few GΩ). The low noise electronic and LabVIEW program interface are also presented. The point contact regime and the large-scale motion capabilities are of particular interest for mapping and testing the superconducting properties of macroscopic scale superconductor-based devices.

  6. Summary of revised potentiometric-surface map for Yucca Mountain and vicinity, Nevada

    USGS Publications Warehouse

    Ervin, E.M.; Luckey, R.R.; Burkhardt, D.J.

    1993-01-01

    The revised map for the potentiometric surface of the uppermost saturated zone in Tertiary volcanic rocks at Yucca Mountain, Nevada, is based mainly on 1988 water levels. Refinement of the water-level corrections has increased understanding of the area immediately east-southeast and hydrologically downgradient of Yucca Mountain. This small-gradient area is a nearly horizontal surface which corresponds to the likely direction of ground-water flow from Yucca Mountain - east-southeast. To the west of Yucca Mountain, water levels are approximately 45 m higher than those in the small-gradient area, and to the east of the northern part of Yucca Mountain water levels are approximately 300 m higher than those in the small-gradient area. Water levels are higher to the west of Yucca Mountain apparently because of a barrier to ground-water flow formed by the Solitario Canyon fault and a splay of the fault, and water levels are higher to the north apparently because of a semi-perched ground-water system.

  7. Automated mapping of impervious surfaces in urban and suburban areas: Linear spectral unmixing of high spatial resolution imagery

    NASA Astrophysics Data System (ADS)

    Yang, Jian; He, Yuhong

    2017-02-01

    Quantifying impervious surfaces in urban and suburban areas is a key step toward a sustainable urban planning and management strategy. With the availability of fine-scale remote sensing imagery, automated mapping of impervious surfaces has attracted growing attention. However, the vast majority of existing studies have selected pixel-based and object-based methods for impervious surface mapping, with few adopting sub-pixel analysis of high spatial resolution imagery. This research makes use of a vegetation-bright impervious-dark impervious linear spectral mixture model to characterize urban and suburban surface components. A WorldView-3 image acquired on May 9th, 2015 is analyzed for its potential in automated unmixing of meaningful surface materials for two urban subsets and one suburban subset in Toronto, ON, Canada. Given the wide distribution of shadows in urban areas, the linear spectral unmixing is implemented in non-shadowed and shadowed areas separately for the two urban subsets. The results indicate that the accuracy of impervious surface mapping in suburban areas reaches up to 86.99%, much higher than the accuracies in urban areas (80.03% and 79.67%). Despite its merits in mapping accuracy and automation, the application of our proposed vegetation-bright impervious-dark impervious model to map impervious surfaces is limited due to the absence of soil component. To further extend the operational transferability of our proposed method, especially for the areas where plenty of bare soils exist during urbanization or reclamation, it is still of great necessity to mask out bare soils by automated classification prior to the implementation of linear spectral unmixing.

  8. Map showing how the potentiometric surface of the Magothy Aquifer of August 1980 differed from the potentiometric surface of September 1977, in southern Maryland

    USGS Publications Warehouse

    Mack, Frederick K.; Wheeler, J.C.; Curtin, Stephen E.

    1982-01-01

    The map is based on the differences between two sets of water-level measurements made in 65 observation wells. One set was made in 1977, a relatively dry year, and the other set was made in 1980, another relatively dry year. The map shows that the potentiometric surface was higher in 1980, by as much as 9 feet, than it was in 1977, in a band a few miles wide near the outcrop and subcrop areas of the aquifer in northern Prince Georges County and central Anne Arundel County. In the remainder of the map area, the 1980 potentiometric surface was lower than it had been in 1977, with declines as great as 20 feet measured in well fields at Waldorf and Chalk Point. The network of observation wells was developed and is operated and maintained as part of the cooperative program between the U.S. Geological Survey and agencies of the Maryland Department of Natural Resources. (USGS)

  9. Near-surface gas mapping studies of salt geologic features at Weeks Island and other sites

    SciTech Connect

    Molecke, M.A.; Carney, K.R.; Autin, W.J.; Overton, E.B.

    1996-10-01

    Field sampling and rapid gas analysis techniques were used to survey near-surface soil gases for geotechnical diagnostic purposes at the Weeks Island Strategic Petroleum Reserve (SPR) site and other salt dome locations in southern Louisiana. This report presents the complete data, results and interpretations obtained during 1995. Weeks Island 1994 gas survey results are also briefly summarized; this earlier study did not find a definitive correlation between sinkhole No. 1 and soil gases. During 1995, several hundred soil gas samples were obtained and analyzed in the field by gas chromatography, for profiling low concentrations and gas anomalies at ppm to percent levels. The target gases included hydrogen, methane, ethane and ethylene. To supplement the field data, additional gas samples were collected at various site locations for laboratory analysis of target gases at ppb levels. Gases in the near-surface soil originate predominantly from the oil, from petrogenic sources within the salt, or from surface microbial activity. Surveys were conducted across two Weeks Island sinkholes, several mapped anomalous zones in the salt, and over the SPR repository site and its perimeter. Samples were also taken at other south Louisiana salt dome locations for comparative purposes. Notable results from these studies are that elevated levels of hydrogen and methane (1) were positively associated with anomalous gassy or shear zones in the salt dome(s) and (2) are also associated with suspected salt fracture (dilatant) zones over the edges of the SPR repository. Significantly elevated areas of hydrogen, methane, plus some ethane, were found over anomalous shear zones in the salt, particularly in a location over high pressure gas pockets in the salt, identified in the mine prior to SPR operations. Limited stable isotope ratio analyses, SIRA, were also conducted and determined that methane samples were of petrogenic origin, not biogenic.

  10. Multifractal and Singularity Maps of soil surface moisture distribution derived from 2D image analysis.

    NASA Astrophysics Data System (ADS)

    Cumbrera, Ramiro; Millán, Humberto; Martín-Sotoca, Juan Jose; Pérez Soto, Luis; Sanchez, Maria Elena; Tarquis, Ana Maria

    2016-04-01

    methods for mapping geochemical anomalies caused by buried sources and for predicting undiscovered mineral deposits in covered areas. Journal of Geochemical Exploration, 122, 55-70. Cumbrera, R., Ana M. Tarquis, Gabriel Gascó, Humberto Millán (2012) Fractal scaling of apparent soil moisture estimated from vertical planes of Vertisol pit images. Journal of Hydrology (452-453), 205-212. Martin Sotoca; J.J. Antonio Saa-Requejo, Juan Grau and Ana M. Tarquis (2016). Segmentation of singularity maps in the context of soil porosity. Geophysical Research Abstracts, 18, EGU2016-11402. Millán, H., Cumbrera, R. and Ana M. Tarquis (2016) Multifractal and Levy-stable statistics of soil surface moisture distribution derived from 2D image analysis. Applied Mathematical Modelling, 40(3), 2384-2395.

  11. A Fine-Resolution Radar for Mapping Near-Surface Isochronous Layers

    NASA Astrophysics Data System (ADS)

    Rink, T. P.; Kanagaratnam, P.; Braaten, D.; Zimmerman, K.; Akins, T.; Gogineni, S.

    2005-12-01

    Information on the spatial and temporal variation of snow accumulation is required for interpreting satellite-based radar and laser surface elevation measurements made by CryoSAT and ICESAT altimeters. Current methods of using ice cores and analyzing snow pit stratigraphy is time consuming and prone to errors in spatial representation due to the sparse sampling. Remote sensing methods that can map near-surface internal layers for estimating spatial and temporal variation are required. To accomplish this, we developed a 12-18 GHz FMCW radar to map near-surface layers with 3 cm vertical resolution to a depth of about 10 m. We developed the system to be mobile and self-contained so that spatial variability of the accumulation over a large area can be characterized. The fine resolution of this radar is achieved by its wide bandwidth and by illuminating the target area with a plane-wave, which is implemented using an offset-fed parabolic reflector. Traditional wide-beamwidth antennas are susceptible to spherical wave scattering from off-vertical targets that can potentially mask weaker reflections from internal layers. The radar features a fast transmit waveform synthesizer implemented using a voltage controlled oscillator (VCO) and a phase-locked loop (PLL) using a linear chirp as the reference. The highly linear reference chirp was generated by a direct digital synthesis (DDS) waveform generator and compared against the instantaneous output of the VCO to create a highly linear 12 to 18 GHz transmit chirp. The waveform synthesizer can be swept from 12 to 18 GHz in 500 microseconds. The antenna was mounted on a sled and the radar system was integrated with the antenna feed. We designed and built the sled with a gimbaled antenna mount and sensing control system to ensure that the antenna points at nadir. The radar system was successfully tested at the Summit camp, Greenland, in July 2005. We collected a large amount of data from various locations around Summit camp. The

  12. Color Shaded-Relief and Surface-Classification Maps of the Fish Creek Area, Harrison Bay Quadrangle, Northern Alaska

    USGS Publications Warehouse

    Mars, John L.; Garrity, Christopher P.; Houseknecht, David W.; Amoroso, Lee; Meares, Donald C.

    2007-01-01

    Introduction The northeastern part of the National Petroleum Reserve in Alaska (NPRA) has become an area of active petroleum exploration during the past five years. Recent leasing and exploration drilling in the NPRA requires the U.S. Bureau of Land Management (BLM) to manage and monitor a variety of surface activities that include seismic surveying, exploration drilling, oil-field development drilling, construction of oil-production facilities, and construction of pipelines and access roads. BLM evaluates a variety of permit applications, environmental impact studies, and other documents that require rapid compilation and analysis of data pertaining to surface and subsurface geology, hydrology, and biology. In addition, BLM must monitor these activities and assess their impacts on the natural environment. Timely and accurate completion of these land-management tasks requires elevation, hydrologic, geologic, petroleum-activity, and cadastral data, all integrated in digital formats at a higher resolution than is currently available in nondigital (paper) formats. To support these land-management tasks, a series of maps was generated from remotely sensed data in an area of high petroleum-industry activity (fig. 1). The maps cover an area from approximately latitude 70?00' N. to 70?30' N. and from longitude 151?00' W. to 153?10' W. The area includes the Alpine oil field in the east, the Husky Inigok exploration well (site of a landing strip) in the west, many of the exploration wells drilled in NPRA since 2000, and the route of a proposed pipeline to carry oil from discovery wells in NPRA to the Alpine oil field. This map area is referred to as the 'Fish Creek area' after a creek that flows through the region. The map series includes (1) a color shaded-relief map based on 5-m-resolution data (sheet 1), (2) a surface-classification map based on 30-m-resolution data (sheet 2), and (3) a 5-m-resolution shaded relief-surface classification map that combines the shaded

  13. The effects of AVIRIS atmospheric calibration methodology on identification and quantitative mapping of surface mineralogy, Drum Mountains, Utah

    NASA Technical Reports Server (NTRS)

    Kruse, Fred A.; Dwyer, John L.

    1993-01-01

    The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) measures reflected light in 224 contiguous spectra bands in the 0.4 to 2.45 micron region of the electromagnetic spectrum. Numerous studies have used these data for mineralogic identification and mapping based on the presence of diagnostic spectral features. Quantitative mapping requires conversion of the AVIRIS data to physical units (usually reflectance) so that analysis results can be compared and validated with field and laboratory measurements. This study evaluated two different AVIRIS calibration techniques to ground reflectance: an empirically-based method and an atmospheric model based method to determine their effects on quantitative scientific analyses. Expert system analysis and linear spectral unmixing were applied to both calibrated data sets to determine the effect of the calibration on the mineral identification and quantitative mapping results. Comparison of the image-map results and image reflectance spectra indicate that the model-based calibrated data can be used with automated mapping techniques to produce accurate maps showing the spatial distribution and abundance of surface mineralogy. This has positive implications for future operational mapping using AVIRIS or similar imaging spectrometer data sets without requiring a priori knowledge.

  14. Global Distribution of Shallow Water on Mars: Neutron Mapping of Summer-Time Surface by HEND/Odyssey

    NASA Technical Reports Server (NTRS)

    Mitrofanov, I. G.; Litvak, M. L.; Kozyrev, A. S.; Sanin, A. B.; Tretyakov, V. I.; Boynton, W.; Hamara, D.; Shinohara, C.; Saunders, R. S.; Drake, D.

    2003-01-01

    Orbital mapping of induced neutrons and gamma-rays by Odyssey has recently successfully proven the applicability of nuclear methods for studying of the elementary composition of Martian upper-most subsurface. In particular, the suite of Gamma-Ray Spectrometer (GRS) has discovered the presence of large water-ice rich regions southward and northward on Mars. The data of neutron mapping of summer-time surface are presented below from the Russian High Energy Neutron Spectrometer (HEND), which is a part of GRS suite. These maps represent the content of water in the soil for summer season at Southern and Northern hemispheres, when the winter deposit of CO2 is absent on the surface. The seasonal evolution of CO2 coverage on Mars is the subject of the complementary paper.

  15. Advances in soil mapping: Mapping quartz content of soil surface using airborne hyperspectral remote sensing in the longwave-infrared region

    NASA Astrophysics Data System (ADS)

    Weksler, Shahar; Notesco, Gila; Ben-Dor, Eyal

    2016-04-01

    Hyperspectral remote sensing in the longwave-infrared (LWIR) spectral region has proven to be a new and efficient tool for mineral mapping (Adar et al. 2013). Minerals which are featureless in the visible, near-infrared and shortwave-infrared regions, e.g., quartz, have a unique fingerprint in the LWIR region (8-12 μm). This spectral region adds to the optical region in which several important minerals can be characterized with significant features (e.g., clay). Accordingly, using airborne hyperspectral remote-sensing data in the LWIR region is an important and practical means of classifying and quantifying minerals. Day and night airborne data, acquired by the AisaOWL sensor over Nitzana National Park in Israel, were used to demonstrate how LWIR region data can be used to map quartz content on the soil surface in a pixel-by-pixel process. The LWIR radiance image is composed of the surface emissivity (and hence the surface's chemical and physical properties), the radiant temperature (according to the Plank equation) and the atmospheric attenuation (which is different during the day and at night). In this work, we show that it is possible to separate surface emissivity, temperature and atmospheric attenuation by using the radiance measured from a vicarious calibration site which was found to be distinctive for the atmospheric contribution. Applying the spectrum of this area as a gain factor to each pixel in the image reduced the atmospheric effects while emphasizing the mineralogical features. Based on this finding and using the same vicarious calibration site used by Notesco et al. (2015), we further studied the possibility of mapping quartz in an area outside the vicarious calibration site. The resulting emissivity image of Nitzana soils (100 km away from the vicarious calibration site) enabled quantifying the quartz in each pixel and mapping its abundance. The day and night images showed a similar quartz distribution, thereby validating the methodology and

  16. A first look at the application of signal extraction techniques to the analysis of body surface potential maps

    NASA Technical Reports Server (NTRS)

    Weinstein, S. B.; Mcneel, M. L.; Matthews, E.; Fischmann, E. J.

    1976-01-01

    Partial body surface potential maps from both normal subjects and subjects with independently diagnosed myocardial infarcts are visually compared from superimposed plots. A correlation test is devised to distinguish the two groups, with the reference waveform determined by means of a gradient-search algorithm. The results are encouraging, and suggest further investigation of these techniques as a future diagnostic tool.

  17. Global 30m 2000-2014 Surface Water Dynamics Map Derived from All Landsat 5, 7, and 8

    NASA Astrophysics Data System (ADS)

    Hudson, A.; Hansen, M.

    2015-12-01

    Water is critical for human life, agriculture, and ecosystems. A better understanding of where it is and how it is changing will enable better management of this valuable resource and guide protection of sensitive ecological areas. Global water maps have typically been representations of surface water at one given time. However, there is both seasonal and interannual variability: rivers meander, lakes disappear, floods arise. To address this ephemeral nature of water, in this study University of Maryland has developed a method that analyzes every Landsat 5, 7, and 8 scene from 1999-2015 to produce global seasonal maps (Winter, Spring, Summer, Fall) of surface water dynamics from 2000-2014. Each Landsat scene is automatically classified into land, water, cloud, haze, shadow, and snow via a decision tree algorithm. The land and water observations are aggregated per pixel into percent occurrence of water in a 3 year moving window for each meteorological season. These annual water percentages form a curve for each season that is discretized into a continuous 3 band RGB map. Frequency of water observation and type of surface water change (loss, gain, peak, or dip) is clearly seen through brightness and hue respectively. Additional data layers include: the year the change began, peak year, minimum year, and the year the change process ended. Currently these maps have been created for 18 1°x1° test tiles scattered around the world, and a portion of the September-November map over Bangladesh is shown below. The entire Landsat archive from 1999-2015 will be processed through a partnership with Google Earth Engine to complete the global product in the coming months. In areas where there is sufficient satellite data density (e.g. the United States), this project could be expanded to 1984-2015. This study provides both scientific researchers and the public an understandable, temporally rich, and globally consistent map showing surface water changes over time.

  18. High-precision geologic mapping to evaluate the potential for seismic surface rupture at TA-55, Los Alamos National Laboratory

    SciTech Connect

    Gardner, J.N.; Lavine, A.; Vaniman, D.; WoldeGabriel, G.

    1998-06-01

    In this report the authors document results of high-precision geologic mapping in the vicinity of TA-55 that has been done to identify parts of the southern portion of the Rendija Canyon Fault, or any other faults, with the potential for seismic surface rupture. To assess the potential for surface rupture at TA-55, an area of approximately 3 square miles that includes the Los Alamos County Landfill and Twomile, Mortandad, and Sandia Canyons has been mapped in detail. Map units are mostly cooling or flow units within the Tshirege Member (1.2 Ma) of the Bandelier Tuff. Stratigraphic markers that are useful for determining offsets in the map area include a distinct welding break at or near the cooling Unit 2-Unit 3 contact, and the Unit 3-Unit 4 contact. At the County Landfill the contact between the Tshirege Member of the Bandelier Tuff and overlying Quaternary alluvium has also been mapped. The mapping indicates that there is no faulting in the near-surface directly below TA-55, and that the closest fault is about 1500 feet west of the Plutonium Facility. Faulting is more abundant on the western edge of the map area, west of TA-48 in uppermost Mortandad Canyon, upper Sandia Canyon, and at the County Landfill. Measured vertical offsets on the faults range from 1 to 8 feet on mapped Bandelier Tuff contacts. Faulting exposed at the Los Alamos County Landfill has deformed a zone over 1000 feet wide, and has a net vertical down-to-the-west displacement of at least 15 feet in the Bandelier Tuff. Individual faults at the landfill have from less than 1 foot to greater than 15 feet of vertical offset on the Bandelier Tuff. Most faults in the landfill trend N-S, N20W, or N45E. Results of the mapping indicate that the Rendija Canyon Fault does not continue directly south to TA-55. At present, the authors have insufficient data to connect faulting they have mapped to areas of known faulting to the north or south of the study area.

  19. Multi-elemental surface mapping and analysis of carbonaceous shale by laser-induced breakdown spectroscopy

    NASA Astrophysics Data System (ADS)

    Xu, Tao; Liu, Jie; Shi, Qi; He, Yi; Niu, Guanghui; Duan, Yixiang

    2016-01-01

    Gas shale is one of the important unconventional hydrocarbon source rocks, whose composition, such as mineral components and redox sensitive trace elements, has been proved as important geochemical proxies playing essential roles in indicating the gas potential and gas productivity in recent geological researches. Fast and accurate measurements for the shale composition, especially those with spatial resolution, will reveal rich information for the understanding and evaluation of gas shale reservoirs. In this paper, we demonstrated the potentiality as well as feasibility of laser-induced breakdown spectroscopy as an effective technique to perform spectrochemical analysis for shale samples. In case of the bulk analysis of pressed shale pellet, spectral analysis of the plasma emission revealed high sensitivity of LIBS for major, minor and even trace elements. More than 356 lines emitted by 19 different elements can be found. Among these species, redox sensitive trace elements such as V, Cr, and Ni were detected with high signal-to-ratios. Two-dimensional surface micro-analysis for the concerned major or minor elements with strong emissions was then applied to the smoothed shale slab. Local thermodynamic equilibrium for the plasma was first verified with a line profile point-by-point on the sample surface, the matrix effect was then assessed as negligible by the extracted electron density and temperature of the plasmas induced at each position on the same profile. Concentration mappings for the major elements of Si, Al, Fe, Ca, Mg, Na and K were finally constructed with their measured relative variations of line emission intensities. The distribution and correlations of these elements in concentration may reflect changes of shale mineral components with respected to the variations of the depositional environments and provide an important clue in identifying sedimentary processes when combined with other geological or geochemical evidences. These results well

  20. Use of sequence-bounding surfaces for correlation and mapping in nonmarine, Incised-Valley reservoirs

    SciTech Connect

    Leckie, D.A.; Vanbeselaere, N.

    1995-11-01

    One of the problems with the application of sequence stratigraphy to nonmarine sediments is the use of effective surfaces for correlations. This case study from the Mannville Group of southern Saskatchewan demonstrates how major, regional bounding surfaces can be identified and correlated to produce a suite of maps that can be used for exploration purposes. In southern Saskatchewan, Cretaceous Mannville sediments, termed the Pense, Cantuar, and Success (S2) formations, overlie Jurassic S1 and older deposits. The interval, which is up to 100 m thick, was deposited over 40 to 50 m.y. and is riddled with unconformities and weathered horizons. Detailed stratigraphic correlations using well logs are difficult, imprecise, and highly suspect unless corroborated by core control. Jurassic Success S1 sediment was deposited in a restricted shallow-marine environment. The S2 was deposited as a sheet of quartzose, braided fluvial sandstone that unconformably cuts into the S1. The overlying Cantuar Formation consists of dominantly lithic sandstone, siltstone, and shale overlying a basal quartzose unit. The base of the Cantuar Formation has a high local relief and in places has eroded long, wide valleys into the Success and older Jurassic strata. The valleys were hundreds of kilometers long and up to 74 in deep. Remnants of the Success sediment are preserved as isolated, buried cuestas on the margins of the valley walls. Cantuar sediments represent the infill of an extensive valley system that took millions of years to fill. The fill was from meandering streams with abundant paleosols, shallow lacustrine, and splay deposits. The top of the Cantuar Formation is represented by chert and quartzose sandstones deposited in a north-south-trending estuarine system with several tributaries. Several play types, which are dominantly stratigraphic, have been identified and are related to the valley incision, valley fill, and preserved erosional cuesta remnants.

  1. Self-organizing adaptive map: autonomous learning of curves and surfaces from point samples.

    PubMed

    Piastra, Marco

    2013-05-01

    Competitive Hebbian Learning (CHL) (Martinetz, 1993) is a simple and elegant method for estimating the topology of a manifold from point samples. The method has been adopted in a number of self-organizing networks described in the literature and has given rise to related studies in the fields of geometry and computational topology. Recent results from these fields have shown that a faithful reconstruction can be obtained using the CHL method only for curves and surfaces. Within these limitations, these findings constitute a basis for defining a CHL-based, growing self-organizing network that produces a faithful reconstruction of an input manifold. The SOAM (Self-Organizing Adaptive Map) algorithm adapts its local structure autonomously in such a way that it can match the features of the manifold being learned. The adaptation process is driven by the defects arising when the network structure is inadequate, which cause a growth in the density of units. Regions of the network undergo a phase transition and change their behavior whenever a simple, local condition of topological regularity is met. The phase transition is eventually completed across the entire structure and the adaptation process terminates. In specific conditions, the structure thus obtained is homeomorphic to the input manifold. During the adaptation process, the network also has the capability to focus on the acquisition of input point samples in critical regions, with a substantial increase in efficiency. The behavior of the network has been assessed experimentally with typical data sets for surface reconstruction, including suboptimal conditions, e.g. with undersampling and noise.

  2. Mid-infrared thermal imaging for an effective mapping of surface materials and sub-surface detachments in mural paintings: integration of thermography and thermal quasi-reflectography

    NASA Astrophysics Data System (ADS)

    Daffara, C.; Parisotto, S.; Mariotti, P. I.

    2015-06-01

    Cultural Heritage is discovering how precious is thermal analysis as a tool to improve the restoration, thanks to its ability to inspect hidden details. In this work a novel dual mode imaging approach, based on the integration of thermography and thermal quasi-reflectography (TQR) in the mid-IR is demonstrated for an effective mapping of surface materials and of sub-surface detachments in mural painting. The tool was validated through a unique application: the "Monocromo" by Leonardo da Vinci in Italy. The dual mode acquisition provided two spatially aligned dataset: the TQR image and the thermal sequence. Main steps of the workflow included: 1) TQR analysis to map surface features and 2) to estimate the emissivity; 3) projection of the TQR frame on reference orthophoto and TQR mosaicking; 4) thermography analysis to map detachments; 5) use TQR to solve spatial referencing and mosaicking for the thermal-processed frames. Referencing of thermal images in the visible is a difficult aspect of the thermography technique that the dual mode approach allows to solve in effective way. We finally obtained the TQR and the thermal maps spatially referenced to the mural painting, thus providing the restorer a valuable tool for the restoration of the detachments.

  3. PLUTO AND CHARON WITH THE HUBBLE SPACE TELESCOPE. II. RESOLVING CHANGES ON PLUTO'S SURFACE AND A MAP FOR CHARON

    SciTech Connect

    Buie, Marc W.; Young, Eliot F.; Young, Leslie A.; Stern, S. Alan; Grundy, William M. E-mail: efy@boulder.swri.edu E-mail: alan@boulder.swri.edu

    2010-03-15

    We present new imaging of the surface of Pluto and Charon obtained during 2002-2003 with the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) instrument. Using these data, we construct two-color albedo maps for the surfaces of both Pluto and Charon. Similar mapping techniques are used to re-process HST/Faint Object Camera (FOC) images taken in 1994. The FOC data provide information in the ultraviolet and blue wavelengths that show a marked trend of UV-bright material toward the sunlit pole. The ACS data are taken at two optical wavelengths and show widespread albedo and color variegation on the surface of Pluto and hint at a latitudinal albedo trend on Charon. The ACS data also provide evidence for a decreasing albedo for Pluto at blue (435 nm) wavelengths, while the green (555 nm) data are consistent with a static surface over the one-year period of data collection. We use the two maps to synthesize a true visual color map of Pluto's surface and investigate trends in color. The mid- to high-latitude region on the sunlit pole is, on average, more neutral in color and generally higher albedo than the rest of the surface. Brighter surfaces also tend to be more neutral in color and show minimal color variations. The darker regions show considerable color diversity arguing that there must be a range of compositional units in the dark regions. Color variations are weak when sorted by longitude. These data are also used to constrain astrometric corrections that enable more accurate orbit fitting, both for the heliocentric orbit of the barycenter and the orbit of Pluto and Charon about their barycenter.

  4. Scanning probe acceleration microscopy (SPAM) in fluids: Mapping mechanical properties of surfaces at the nanoscale

    PubMed Central

    Legleiter, Justin; Park, Matthew; Cusick, Brian; Kowalewski, Tomasz

    2006-01-01

    One of the major thrusts in proximal probe techniques is combination of imaging capabilities with simultaneous measurements of physical properties. In tapping mode atomic force microscopy (TMAFM), the most straightforward way to accomplish this goal is to reconstruct the time-resolved force interaction between the tip and surface. These tip–sample forces can be used to detect interactions (e.g., binding sites) and map material properties with nanoscale spatial resolution. Here, we describe a previously unreported approach, which we refer to as scanning probe acceleration microscopy (SPAM), in which the TMAFM cantilever acts as an accelerometer to extract tip–sample forces during imaging. This method utilizes the second derivative of the deflection signal to recover the tip acceleration trajectory. The challenge in such an approach is that with real, noisy data, the second derivative of the signal is strongly dominated by the noise. This problem is solved by taking advantage of the fact that most of the information about the deflection trajectory is contained in the higher harmonics, making it possible to filter the signal by “comb” filtering, i.e., by taking its Fourier transform and inverting it while selectively retaining only the intensities at integer harmonic frequencies. Such a comb filtering method works particularly well in fluid TMAFM because of the highly distorted character of the deflection signal. Numerical simulations and in situ TMAFM experiments on supported lipid bilayer patches on mica are reported to demonstrate the validity of this approach. PMID:16551751

  5. Multi-pollutant surface objective analyses and mapping of air quality health index over North America.

    PubMed

    Robichaud, Alain; Ménard, Richard; Zaïtseva, Yulia; Anselmo, David

    2016-01-01

    Air quality, like weather, can affect everyone, but responses differ depending on the sensitivity and health condition of a given individual. To help protect exposed populations, many countries have put in place real-time air quality nowcasting and forecasting capabilities. We present in this paper an optimal combination of air quality measurements and model outputs and show that it leads to significant improvements in the spatial representativeness of air quality. The product is referred to as multi-pollutant surface objective analyses (MPSOAs). Moreover, based on MPSOA, a geographical mapping of the Canadian Air Quality Health Index (AQHI) is also presented which provides users (policy makers, public, air quality forecasters, and epidemiologists) with a more accurate picture of the health risk anytime and anywhere in Canada and the USA. Since pollutants can also behave as passive atmospheric tracers, they provide information about transport and dispersion and, hence, reveal synoptic and regional meteorological phenomena. MPSOA could also be used to build air pollution climatology, compute local and national trends in air quality, and detect systematic biases in numerical air quality (AQ) models. Finally, initializing AQ models at regular time intervals with MPSOA can produce more accurate air quality forecasts. It is for these reasons that the Canadian Meteorological Centre (CMC) in collaboration with the Air Quality Research Division (AQRD) of Environment Canada has recently implemented MPSOA in their daily operations.

  6. An airborne robotic platform for mapping thermal structure in surface water bodies

    NASA Astrophysics Data System (ADS)

    Thompson, S. E.; Chung, M.; Detweiler, C.; Ore, J. P.

    2015-12-01

    The significance of thermal heterogeneities in small surface water bodies as drivers of mixing and for habitat provision is increasingly recognized, yet obtaining three-dimensionally resolved observations of the thermal structure of lakes and rivers remains challenging. For relatively shallow water bodies, observations of water temperature from aerial platforms are attractive: they do not require shoreline access, they can be quickly and easily deployed and redeployed, facilitating repeated sampling, and they can rapidly move between measurement locations, allowing multiple measurements to be made during single flights. However, they are also subject to well-known limitations including payload, flight duration and operability, and their effectiveness as a mobile platform for thermal sensing is still poorly characterized. In this talk, I will introduce an aerial thermal sensing platform that enables water temperature measurements to be made and spatially located throughout a water column, and present preliminary results from initial field experiments comparing in-situ temperature observations to those made from the UAS platform. The results highlight the potential scalability of the platform to provide high-resolution 3D thermal mapping of a ~1 ha lake in 2-3 flights (circa 1 hour), sufficient to resolve diurnal variations. Operability constraints and key needs for further development are also identified.

  7. Scanning probe acceleration microscopy (SPAM) in fluids: Mapping mechanical properties of surfaces at the nanoscale

    NASA Astrophysics Data System (ADS)

    Legleiter, Justin; Park, Matthew; Cusick, Brian; Kowalewski, Tomasz

    2006-03-01

    One of the major thrusts in proximal probe techniques is combination of imaging capabilities with simultaneous measurements of physical properties. In tapping mode atomic force microscopy (TMAFM), the most straightforward way to accomplish this goal is to reconstruct the time-resolved force interaction between the tip and surface. These tip-sample forces can be used to detect interactions (e.g., binding sites) and map material properties with nanoscale spatial resolution. Here, we describe a previously unreported approach, which we refer to as scanning probe acceleration microscopy (SPAM), in which the TMAFM cantilever acts as an accelerometer to extract tip-sample forces during imaging. This method utilizes the second derivative of the deflection signal to recover the tip acceleration trajectory. The challenge in such an approach is that with real, noisy data, the second derivative of the signal is strongly dominated by the noise. This problem is solved by taking advantage of the fact that most of the information about the deflection trajectory is contained in the higher harmonics, making it possible to filter the signal by “comb” filtering, i.e., by taking its Fourier transform and inverting it while selectively retaining only the intensities at integer harmonic frequencies. Such a comb filtering method works particularly well in fluid TMAFM because of the highly distorted character of the deflection signal. Numerical simulations and in situ TMAFM experiments on supported lipid bilayer patches on mica are reported to demonstrate the validity of this approach.

  8. Scanning probe acceleration microscopy (SPAM) in fluids: mapping mechanical properties of surfaces at the nanoscale.

    PubMed

    Legleiter, Justin; Park, Matthew; Cusick, Brian; Kowalewski, Tomasz

    2006-03-28

    One of the major thrusts in proximal probe techniques is combination of imaging capabilities with simultaneous measurements of physical properties. In tapping mode atomic force microscopy (TMAFM), the most straightforward way to accomplish this goal is to reconstruct the time-resolved force interaction between the tip and surface. These tip-sample forces can be used to detect interactions (e.g., binding sites) and map material properties with nanoscale spatial resolution. Here, we describe a previously unreported approach, which we refer to as scanning probe acceleration microscopy (SPAM), in which the TMAFM cantilever acts as an accelerometer to extract tip-sample forces during imaging. This method utilizes the second derivative of the deflection signal to recover the tip acceleration trajectory. The challenge in such an approach is that with real, noisy data, the second derivative of the signal is strongly dominated by the noise. This problem is solved by taking advantage of the fact that most of the information about the deflection trajectory is contained in the higher harmonics, making it possible to filter the signal by "comb" filtering, i.e., by taking its Fourier transform and inverting it while selectively retaining only the intensities at integer harmonic frequencies. Such a comb filtering method works particularly well in fluid TMAFM because of the highly distorted character of the deflection signal. Numerical simulations and in situ TMAFM experiments on supported lipid bilayer patches on mica are reported to demonstrate the validity of this approach.

  9. Experimental investigation of free surface vortices and definition of gas entrainment occurrence maps

    NASA Astrophysics Data System (ADS)

    Caruso, G.; Cristofano, L.; Nobili, M.; Vitale Di Maio, D.

    2014-04-01

    For the future development of Generation IV nuclear reactors, both safety and economic targets have to be achieved. In order to increase, at the same time, the power density generation and the safety features, a huge R&D effort is still required. Referring especially to Liquid Metal Cooled Fast Reactors, much attention is placed on Gas Entrainment (GE) phenomena, which could cause unlikely positive reactivity insertion accident. The GETS experimental facility (Gas Entrainment Test Section), especially aimed at studying the free surface vortices occurrence, has been built in the thermal-hydraulics laboratory of the DIAEE. The main purpose of this facility is to identify the most important parameters affecting the whirlpools formation and evolution. Experimental tests and preliminary observations have been performed. Different vortex behaviours related to different experimental conditions have been identified and presented in the present paper. 2D occurrence maps as function of different dimensionless groups (Reynolds, Froude and Weber numbers and H* = H/d ratio) have been defined. In the present paper, the results of a first experimental campaign, carried out with tap water, are discussed.

  10. Global mapping of Lithosphere/Asthenosphere Boundary from surface wave tomography

    NASA Astrophysics Data System (ADS)

    Burgos, G.; Montagner, J.; Beucler, E.; Trampert, J.; Ritzwoller, M. H.; Capdeville, Y.; Shapiro, N. M.

    2010-12-01

    The coupling between rigid lithosphere and the weaker underlying asthenosphere is a key point of Plate Tectonics and Mantle dynamics. The characterization of the properties of the Lithosphere/Asthenosphere Boundary (LAB) is essential for understanding the Upper Mantle. Recent studies, using receiver functions for example, provide local constraints. In this study a global view by surface wave tomography is given. A large amount of data from different groups (Harvard, Boulder, Utrecht, Paris) has been collected. There are more than 100,000 phase and group velocicties measurements on the fundamental mode of Rayleigh and Love waves. This global scale dataset in the period range 15s-200s, enables us to investigate the LAB with an approximative lateral resolution of 500km. The regionalization of the path-averaged velocities is performed to extract isotropic and azimuthally anisotropic terms of local velocities. First we derive our own crustal model (taking account of topography-bathymetry, sediments and crustal thickness) by a MonteCarlo inversion with the shorter periods of the data. Second, to estimate the LAB properties and obtain a global map, we choose a very simple parameter space ajusted with the larger periods of the data. We report here a good correlation between oceanic inverted LAB depth (~45km average) and ocean floor age, in the sense of the classical thickening of oceanic lithosphere. The determination of LAB beneath continents is more difficult, shallower depths (~90km average) are found in comparison with heat flux studies.

  11. Capacitive ECG system with direct access to standard leads and body surface potential mapping.

    PubMed

    Oehler, Martin; Schilling, Meinhard; Esperer, Hans Dieter

    2009-12-01

    Capacitive electrodes provide the same access to the human electrocardiogram (ECG) as galvanic electrodes, but without the need of direct electrical skin contact and even through layers of clothing. Thus, potential artifacts as a result of poor electrode contact to the skin are avoided and preparation time is significantly reduced. Our system integrates such capacitive electrodes in a 15 sensor array, which is combined with a Tablet PC. This integrated lightweight ECG system (cECG) is easy to place on the chest wall and allows for simultaneous recordings of 14 ECG channels, even if the patient is slightly dressed, e.g., with a t-shirt. In this paper, we present preliminary results on the performance of the cECG regarding the capability of recording body surface potential maps (BSPMs) and obtaining reconstructed standard ECG leads including Einthoven, Goldberger and, with some limitations, Wilson leads. All signals were measured having the subject lie in a supine position and wear a cotton shirt. Signal quality and diagnostic ECG information of the extracted leads are compared with standard ECG measurements. The results show a very close correlation between both types of ECG measurements. It is concluded that the cECG lends itself to rapid screening in clinically unstable patients.

  12. Spatial Mapping of Pyocyanin in Pseudomonas Aeruginosa Bacterial Communities Using Surface Enhanced Raman Scattering.

    PubMed

    Polisetti, Sneha; Baig, Nameera F; Morales-Soto, Nydia; Shrout, Joshua D; Bohn, Paul W

    2017-02-01

    Surface enhanced Raman spectroscopy (SERS) imaging was used in conjunction with principal component analysis (PCA) for the in situ spatiotemporal mapping of the virulence factor pyocyanin in communities of the pathogenic bacterium Pseudomonas aeruginosa. The combination of SERS imaging and PCA analysis provides a robust method for the characterization of heterogeneous biological systems while circumventing issues associated with interference from sample autofluorescence and low reproducibility of SERS signals. The production of pyocyanin is found to depend both on the growth carbon source and on the specific strain of P. aeruginosa studied. A cystic fibrosis lung isolate strain of P. aeruginosa synthesizes and secretes pyocyanin when grown with glucose and glutamate, while the laboratory strain exhibits detectable production of pyocyanin only when grown with glutamate as the source of carbon. Pyocyanin production in the laboratory strain grown with glucose was below the limit of detection of SERS. In addition, the combination of SERS imaging and PCA can elucidate subtle differences in the molecular composition of biofilms. PCA loading plots from the clinical isolate exhibit features corresponding to vibrational bands of carbohydrates, which represent the mucoid biofilm matrix specific to that isolate, features that are not seen in the PCA loading plots of the laboratory strain.

  13. Mapping surface currents from HF radar radial velocity measurements using optimal interpolation

    NASA Astrophysics Data System (ADS)

    Kim, Sung Yong; Terrill, Eric J.; Cornuelle, Bruce D.

    2008-10-01

    An optimal interpolation (OI) method to compute surface vector current fields from radial velocity measurements derived from high-frequency (HF) radars is presented. The method assumes a smooth spatial covariance relationship between neighboring vector currents, in contrast to the more commonly used un-weighted least-squares fitting (UWLS) method, which assumes a constant vector velocity within a defined search radius. This OI method can directly compute any quantities linearly related to the radial velocities, such as vector currents and dynamic quantities (divergence and vorticity) as well as the uncertainties of those respective fields. The OI method is found to be more stable than the UWLS method and reduces spurious vector solutions near the baselines between HF radar installations. The OI method produces a covariance of the uncertainty of the estimated vector current fields. Three nondimensional uncertainty indices are introduced to characterize the uncertainty of the vector current at a point, representing an ellipse with directional characteristics. The vector current estimation using the OI method eliminates the need for multiple mapping steps and optimally fills intermittent coverage gaps. The effects of angular interpolation of radial velocities, a commonly used step in the preprocessing of radial velocity data prior to vector current computation in the UWLS method, are presented.

  14. Preliminary lithogeochemical map showing near-surface rock types in the Chesapeake Bay watershed, Virginia and Maryland

    USGS Publications Warehouse

    Peper, John D.; McCartan, Lucy B.; Horton, J. Wright; Reddy, James E.

    2001-01-01

    and aspects of ground and surface water chemistry could help to refine the lithogeochemical classification, and this map. The testing could also improve the usefulness of the map for assessing aquifer reactivity and the transport properties of reactive contaminants such as acid rain, and nitrate from agricultural sources, in the Chesapeake Bay watershed.

  15. High spatial resolution mapping of surface plasmon resonance modes in single and aggregated gold nanoparticles assembled on DNA strands

    PubMed Central

    2013-01-01

    Abstract We present the mapping of the full plasmonic mode spectrum for single and aggregated gold nanoparticles linked through DNA strands to a silicon nitride substrate. A comprehensive analysis of the electron energy loss spectroscopy images maps was performed on nanoparticles standing alone, dimers, and clusters of nanoparticles. The experimental results were confirmed by numerical calculations using the Mie theory and Gans-Mie theory for solving Maxwell's equations. Both bright and dark surface plasmon modes have been unveiled. PACS 78.67.Bf; 61.46.Df; 87.64.Ee PMID:23890222

  16. The abandoned surface mining sites in the Czech Republic: mapping and creating a database with a GIS web application

    NASA Astrophysics Data System (ADS)

    Pokorný, Richard; Tereza Peterková, Marie

    2016-05-01

    Based on the vectorization of the 55-volume book series the Quarry Inventories of the Czechoslovak Republic/Czechoslovak Socialist Republic, published in the years 1932-1961, a new comprehensive database was built comprising 9958 surface mining sites of raw materials, which were active in the first half of the 20th century. The mapped area covers 40.9 % of the territory of the Czech Republic. For the purposes of visualization, a map application, the Quarry Inventories Online, was created that enables the data visualization.

  17. Response Surface Mapping of Neurobehavioral Performance: Testing the Feasibility of Split Sleep Schedules for Space Operations.

    PubMed

    Mollicone, Daniel J; Van Dongen, Hans P A; Rogers, Naomi L; Dinges, David F

    2008-01-01

    The demands of sustaining high levels of neurobehavioral performance during space operations necessitate precise scheduling of sleep opportunities in order to best preserve optimal performance. We report here the results of the first split-sleep, dose-response experiment involving a range of sleep/wake scenarios with chronically reduced nocturnal sleep, augmented with a diurnal nap. To characterize performance over all combinations of split sleep in the range studied, we used response surface mapping methodology. Waking neurobehavioral performance was studied in N=90 subjects each assigned to one of 18 sleep regimens consisting of a restricted nocturnal anchor sleep period and a diurnal nap. Psychomotor vigilance task performance and subjective assessments of sleepiness were found to be primarily a function of total time in bed per 24 h regardless of how sleep was divided among nocturnal anchor sleep and diurnal nap periods. Digit symbol substitution task performance was also found to be primarily a function of total time in bed per 24 h; however, accounting for nocturnal sleep duration and nap duration separately provided a small but significant enhancement in the variance explained. The results suggest that reductions in total daily sleep result in a near-linear accumulation of impairment regardless of whether sleep is scheduled as a consolidated nocturnal sleep period or split into a nocturnal anchor sleep period and a diurnal nap. Thus, split sleep schedules are feasible and can be used to enhance the flexibility of sleep/work schedules for space operations involving restricted nocturnal sleep due to mission-critical task scheduling. These results are generally applicable to any continuous industrial operation that involves sleep restriction, night operations, and shift work.

  18. Automated mapping of sub-pixel impervious surface area from landsat imagery

    NASA Astrophysics Data System (ADS)

    Kamphaus, Benjamin D.

    The past few decades have seen rapid, global urbanization. Remotely sensed imagery is the best source of information about the extent of urbanization, but extracting urban extent from remotely sensed imagery is often an intensive, supervised task for analysts to perform. This project presents a fully automated method to extract impervious surface area (ISA), an important component of urban expansion, from Landsat TM and similar sensors. These moderate resolution sensors have a multi-decade collection archive, sub-monthly revisit rate and have served as a model for other national and commercial programs. The unsupervised methodology proposed herein, termed the PEEL process (pre-processing, endmember extraction and labeling), is an SMA (spectral mixture analysis) technique that uses as inputs endmembers that have been labeled by a SVM (support vector machine) classification through the fusion of the PanTex GLCM-based texture measure and endmembers drawn from the SMACC (sequential maximum angle convex cone) algorithm. Labels are provided to endmembers with an overall accuracy of 94% across 13 Landsat scenes from different sensor types and of several regions and urban forms. Multiple unmixing methods are tested, with BNMESMA (brightness normalized multiple endmember spectral mixture analysis) performing the best with a RMSE of 0.276. Caution is given regarding the value of RMSE as a metric for comparing method accuracy and more detailed error metrics are introduced. The method is shown as a viable template for mapping ISA across multiple scenes and as a useful framework for analyzing large archives of imagery with a common, automatable methodology.

  19. Response Surface Mapping of Neurobehavioral Performance: Testing the Feasibility of Split Sleep Schedules for Space Operations

    PubMed Central

    Mollicone, Daniel J.; Van Dongen, Hans P.A.; Rogers, Naomi L.; Dinges, David F.

    2008-01-01

    The demands of sustaining high levels of neurobehavioral performance during space operations necessitate precise scheduling of sleep opportunities in order to best preserve optimal performance. We report here the results of the first split-sleep, dose-response experiment involving a range of sleep/wake scenarios with chronically reduced nocturnal sleep, augmented with a diurnal nap. To characterize performance over all combinations of split sleep in the range studied, we used response surface mapping methodology. Waking neurobehavioral performance was studied in N=90 subjects each assigned to one of 18 sleep regimens consisting of a restricted nocturnal anchor sleep period and a diurnal nap. Psychomotor vigilance task performance and subjective assessments of sleepiness were found to be primarily a function of total time in bed per 24 h regardless of how sleep was divided among nocturnal anchor sleep and diurnal nap periods. Digit symbol substitution task performance was also found to be primarily a function of total time in bed per 24 h; however, accounting for nocturnal sleep duration and nap duration separately provided a small but significant enhancement in the variance explained. The results suggest that reductions in total daily sleep result in a near-linear accumulation of impairment regardless of whether sleep is scheduled as a consolidated nocturnal sleep period or split into a nocturnal anchor sleep period and a diurnal nap. Thus, split sleep schedules are feasible and can be used to enhance the flexibility of sleep/work schedules for space operations involving restricted nocturnal sleep due to mission-critical task scheduling. These results are generally applicable to any continuous industrial operation that involves sleep restriction, night operations, and shift work. PMID:19194521

  20. Response surface mapping of neurobehavioral performance: Testing the feasibility of split sleep schedules for space operations

    NASA Astrophysics Data System (ADS)

    Mollicone, Daniel J.; Van Dongen, Hans P. A.; Rogers, Naomi L.; Dinges, David F.

    The demands of sustaining high levels of neurobehavioral performance during space operations necessitate precise scheduling of sleep opportunities in order to best preserve optimal performance. We report here the results of the first split sleep, dose-response experiment involving a range of sleep/wake scenarios with chronically reduced nocturnal sleep, augmented with a diurnal nap. To characterize performance over all combinations of split sleep in the range studied, we used response surface mapping methodology. Waking neurobehavioral performance was studied in N=90 subjects each assigned to one of 18 sleep regimens consisting of a restricted nocturnal anchor sleep period and a diurnal nap. Psychomotor vigilance task performance and subjective assessments of sleepiness were found to be primarily a function of total time in bed per 24 h regardless of how sleep was divided among nocturnal anchor sleep and diurnal nap periods. Digit symbol substitution task performance was also found to be primarily a function of total time in bed per 24 h; however, accounting for nocturnal sleep duration and nap duration separately provided a small but significant enhancement in the variance explained. The results suggest that reductions in total daily sleep result in a near-linear accumulation of impairment regardless of whether sleep is scheduled as a consolidated nocturnal sleep period or split into a nocturnal anchor sleep period and a diurnal nap. Thus, split sleep schedules are feasible and can be used to enhance the flexibility of sleep/work schedules for space operations involving restricted nocturnal sleep due to mission-critical task scheduling. These results are generally applicable to any continuous industrial operation that involves sleep restriction, night operations, and shift work.

  1. Airborne mapping of earth-atmosphere exchange processes and remote sensing of surface characteristics over heterogeneous areas

    SciTech Connect

    Schuepp, P.H.; Ogunjemiyo, S.; Mitic, C.M.

    1996-10-01

    Given the spatial heterogeneity of much of the biosphere, and the difficulty in establishing representative observation points at the surface, airborne flux observations coupled with airborne and satellite-based remote sensing plays an increasing role in the description of surface-atmosphere exchange processes. Our paper summarizes flux mapping procedures based on low level airborne sampling by the Canadian Twin Otter research aircraft, over three ecosystems with different degrees of spatial heterogeneity (grassland, mixed agricultural land and boreal forest). Observations show that the degree to which flux maps for heat, moisture and trace gases are correlated, among themselves and with maps of radiometrically observable surface features, cannot be generalized. This means that, wherever possible, algorithms for the prediction of surface-atmosphere exchange processes based on remote sensing observations should be developed for - and tested in - each structurally different ecosystem. The flexibility of deployment of aircraft serves well, both for the gathering of data to develop such algorithms, as well as for their testing at scales that integrate over an adequate sample of the various components that constitute a spatially heterogeneous ecosystem. 23 refs., 4 figs.

  2. SU-E-J-193: Application of Surface Mapping in Detecting Swallowing for Head-&-Neck Cancer

    SciTech Connect

    Cao, D; Xie, X; Mehta, V; Shepard, D

    2015-06-15

    Purpose: Recent evidence is emerging that long term swallowing function may be improved after radiotherapy for head-&-neck cancer if doses are limited to certain swallowing structures. Immobilization of patients with head-&-neck cancer is typically done with a mask. This mask, however, doesn’t limit patient swallowing. Patient voluntary or involuntary swallowing may introduce significant tumor motion, which can lead to suboptimal delivery. In this study, we have examined the feasibility of using surface mapping technology to detect patient swallowing during treatment and evaluated its magnitude. Methods: The C-RAD Catalyst system was used to detect the patient surface map. A volunteer lying on the couch was used to simulate the patient under treatment. A virtual marker was placed near the throat and was used to monitor the swallowing action. The target motion calculated by the Catalyst system through deformable registration was also collected. Two treatment isocenters, one placed close to the throat and the other placed posterior to the base-of-tongue, were used to check the sensitivity of surface mapping technique. Results: When the patient’s throat is not in the shadow of the patient’s chest, the Catalyst system can clearly identify the swallowing motion. In our tests, the vertical motion of the skin can reach to about 5mm. The calculated target motion can reach up to 1 cm. The magnitude of this calculated target motion is more dramatic when the plan isocenter is closer to the skin surface, which suggests that the Catalyst motion tracking technique is more sensitive to the swallowing motion with a shallower isocenter. Conclusion: Surface mapping can clearly identify patient swallowing during radiation treatment. This information can be used to evaluate the dosimetric impact of the involuntary swallowing. It may also be used to potentially gate head-&-neck radiation treatments. A prospective IRB approved study is currently enrolling patients in our

  3. Sea surface velocities from visible and infrared multispectral atmospheric mapping sensor imagery

    NASA Technical Reports Server (NTRS)

    Pope, P. A.; Emery, W. J.; Radebaugh, M.

    1992-01-01

    High resolution (100 m), sequential Multispectral Atmospheric Mapping Sensor (MAMS) images were used in a study to calculate advective surface velocities using the Maximum Cross Correlation (MCC) technique. Radiance and brightness temperature gradient magnitude images were formed from visible (0.48 microns) and infrared (11.12 microns) image pairs, respectively, of Chandeleur Sound, which is a shallow body of water northeast of the Mississippi delta, at 145546 GMT and 170701 GMT on 30 Mar. 1989. The gradient magnitude images enhanced the surface water feature boundaries, and a lower cutoff on the gradient magnitudes calculated allowed the undesirable sunglare and backscatter gradients in the visible images, and the water vapor absorption gradients in the infrared images, to be reduced in strength. Requiring high (greater than 0.4) maximum cross correlation coefficients and spatial coherence of the vector field aided in the selection of an optimal template size of 10 x 10 pixels (first image) and search limit of 20 pixels (second image) to use in the MCC technique. Use of these optimum input parameters to the MCC algorithm, and high correlation and spatial coherence filtering of the resulting velocity field from the MCC calculation yielded a clustered velocity distribution over the visible and infrared gradient images. The velocity field calculated from the visible gradient image pair agreed well with a subjective analysis of the motion, but the velocity field from the infrared gradient image pair did not. This was attributed to the changing shapes of the gradient features, their nonuniqueness, and large displacements relative to the mean distance between them. These problems implied a lower repeat time for the imagery was needed in order to improve the velocity field derived from gradient imagery. Suggestions are given for optimizing the repeat time of sequential imagery when using the MCC method for motion studies. Applying the MCC method to the infrared

  4. Using dose-surface maps to predict radiation-induced rectal bleeding: a neural network approach

    NASA Astrophysics Data System (ADS)

    Buettner, Florian; Gulliford, Sarah L.; Webb, Steve; Partridge, Mike

    2009-09-01

    The incidence of late-toxicities after radiotherapy can be modelled based on the dose delivered to the organ under consideration. Most predictive models reduce the dose distribution to a set of dose-volume parameters and do not take the spatial distribution of the dose into account. The aim of this study was to develop a classifier predicting radiation-induced rectal bleeding using all available information on the dose to the rectal wall. The dose was projected on a two-dimensional dose-surface map (DSM) by virtual rectum-unfolding. These DSMs were used as inputs for a classification method based on locally connected neural networks. In contrast to fully connected conventional neural nets, locally connected nets take the topology of the input into account. In order to train the nets, data from 329 patients from the RT01 trial (ISRCTN 47772397) were split into ten roughly equal parts. By using nine of these parts as a training set and the remaining part as an independent test set, a ten-fold cross-validation was performed. Ensemble learning was used and 250 nets were built from randomly selected patients from the training set. Out of these 250 nets, an ensemble of expert nets was chosen. The performances of the full ensemble and of the expert ensemble were quantified by using receiver-operator-characteristic (ROC) curves. In order to quantify the predictive power of the shape, ensembles of fully connected conventional neural nets based on dose-surface histograms (DSHs) were generated and their performances were quantified. The expert ensembles performed better than or equally as well as the full ensembles. The area under the ROC curve for the DSM-based expert ensemble was 0.64. The area under the ROC curve for the DSH-based expert ensemble equalled 0.59. This difference in performance indicates that not only volumetric, but also morphological aspects of the dose distribution are correlated to rectal bleeding after radiotherapy. Thus, the shape of the dose

  5. Real-Time Two-Dimensional Mapping of Relative Local Surface Temperatures with a Thin-Film Sensor Array

    PubMed Central

    Li, Gang; Wang, Zhenhai; Mao, Xinyu; Zhang, Yinghuang; Huo, Xiaoye; Liu, Haixiao; Xu, Shengyong

    2016-01-01

    Dynamic mapping of an object’s local temperature distribution may offer valuable information for failure analysis, system control and improvement. In this letter we present a computerized measurement system which is equipped with a hybrid, low-noise mechanical-electrical multiplexer for real-time two-dimensional (2D) mapping of surface temperatures. We demonstrate the performance of the system on a device embedded with 32 pieces of built-in Cr-Pt thin-film thermocouples arranged in a 4 × 8 matrix. The system can display a continuous 2D mapping movie of relative temperatures with a time interval around 1 s. This technique may find applications in a variety of practical devices and systems. PMID:27347969

  6. Mapping surface tidal currents and Changjiang plume in the East China Sea from Geostationary Ocean Color Imager

    NASA Astrophysics Data System (ADS)

    Hu, Zifeng; Wang, Dong-Ping; Pan, Delu; He, Xianqiang; Miyazawa, Yasumasa; Bai, Yan; Wang, Difeng; Gong, Fang

    2016-03-01

    The spatial pattern of the semidiurnal M2 tidal currents in the East China Sea (ECS) is mapped from the Geostationary Ocean Color Imager (GOCI), taking advantage of the satellite's unique 8 hourly local daytime sequential images. The GOCI-derived surface M2 tidal currents are validated with a comprehensive set of twenty-eight surface drifters and four mooring observations. The agreement is outstanding with the error variance less than 10% of the total variance. The gridded GOCI-derived tidal currents are also in good agreement with the Oregon State University (OSU) high-resolution regional tidal model of the China Seas. The detided mean flow shows a strong Changjiang plume extending hundreds of kilometers offshore, in agreement with the concurrent satellite sea surface temperature (SST) and sea surface salinity (SSS) distributions. The observed surface currents are compared with the daily mean flows derived from the Japan Coastal Ocean Predictability Experiment (JCOPE2). The model results are consistent with the observations, showing the sensitivity of Changjiang plume to wind forcing. The study clearly demonstrates the utility of geostationary satellite in mapping the surface currents over a wide (˜400 km), tidally dominated continental shelf.

  7. World Map Showing Surface and Subsurface Distribution, and Lithologic Character of Middle and Late Neoproterozoic Rocks

    USGS Publications Warehouse

    Stewart, John H.

    2007-01-01

    INTRODUCTION The map was prepared to outline the basic information on where Neoproterozoic rocks are present in the World, and of the lithologic character of these rocks. The information provides a better understanding of major Neoproterozoic tectonic subdivisions useful in paleogeographic and plate tectonic reconstructions. The time frame of the map is within the middle and late Neoproterozoic from approximately 870 to 540 Ma and is after widespread Mesoproterozoic Grenville-age collisional events that are considered to have formed the hypothetical supercontinent of Rodinia. Much of the time represented by the map is interpreted to be during the fragmentation of Rodinia. The recognition of Neoproterozoic rocks is commonly difficult because of limited isotopic or paloeontological dating. Thus, some rocks shown on the map could be older or younger than the age indicated. However, at the scale of the map the the problem may be minor. Enough information seems to be available to indicate the general age of the rocks. Many of the successions contain diamictite deposits considered to be glaciogenic and dated as middle or late Neoproterozoic. These deposits thus show a rough correlation of middle and late Neoproterozoic rocks of the world. The map is a Richardson map projection, except for Antarctica which is a polar projection. The map was prepared from about 650 references, shown in the text linked below under 'Sources of Information', used to outline distribution patterns, determine rock types, and provide information on the regional and local geologic framework of the rocks. The focus of the references is on the geologic information needed to prepare the map. Other information, such as plate tectonic reconstructions or paleomagnetic studies is generally not included. The 'Sources of Information' lists references alphabetically for each of 14 regions. In brackets is a code for each area. These codes provide help in locating the specific regions in the references.

  8. Visualization and mapping of neurosurgical functional brain data onto a 3-D MR-based model of the brain surface.

    PubMed

    Modayur, B R; Prothero, J; Rosse, C; Jakobovits, R; Brinkley, J F

    1996-01-01

    The Human Brain Project was initiated with the goal of developing methods for managing and sharing information about the brain. As a prototype Human Brain Project application we are developing a system for organizing, visualizing, integrating and sharing information about human language function. The goal of the brain mapping component of our work, described in this article, is to generate the 3D location and extent of cortical language sites with respect to a uniform, 3D patient coordinate system. The language sites of individual patients can then be combined with or related to other patient data in terms of a Talairach, surface-based, or other deformable coordinate systems. Language site mapping is done by visually comparing an intraoperative photograph with the rendered image (from MRI data). The techniques outlined in this article have been utilized to map cortical language sites of six patients. Preliminary results point to the adequacy of our volume visualizations for language mapping. The strength of the visualization scheme lies in the combination of interactive segmentation with volume and surface visualization. We are now in the process of acquiring more patient data to further validate the usefulness of our method.

  9. Surface Temperature Mapping of the University of Northern Iowa Campus Using High Resolution Thermal Infrared Aerial Imageries

    PubMed Central

    Savelyev, Alexander; Sugumaran, Ramanathan

    2008-01-01

    The goal of this project was to map the surface temperature of the University of Northern Iowa campus using high-resolution thermal infrared aerial imageries. A thermal camera with a spectral bandwidth of 3.0-5.0 μm was flown at the average altitude of 600 m, achieving ground resolution of 29 cm. Ground control data was used to construct the pixel- to-temperature conversion model, which was later used to produce temperature maps of the entire campus and also for validation of the model. The temperature map then was used to assess the building rooftop conditions and steam line faults in the study area. Assessment of the temperature map revealed a number of building structures that may be subject to insulation improvement due to their high surface temperatures leaks. Several hot spots were also identified on the campus for steam pipelines faults. High-resolution thermal infrared imagery proved highly effective tool for precise heat anomaly detection on the campus, and it can be used by university facility services for effective future maintenance of buildings and grounds. PMID:27873800

  10. Rapid quantitative chemical mapping of surfaces with sub-2 nm resolution.

    PubMed

    Lai, Chia-Yun; Perri, Saverio; Santos, Sergio; Garcia, Ricardo; Chiesa, Matteo

    2016-05-05

    We present a theory that exploits four observables in bimodal atomic force microscopy to produce maps of the Hamaker constant H. The quantitative H maps may be employed by the broader community to directly interpret the high resolution of standard bimodal AFM images as chemical maps while simultaneously quantifying chemistry in the non-contact regime. We further provide a simple methodology to optimize a range of operational parameters for which H is in the closest agreement with the Lifshitz theory in order to (1) simplify data acquisition and (2) generalize the methodology to any set of cantilever-sample systems.

  11. Topographic mapping of trans-cranial magnetic stimulation data on surface rendered MR images of the brain.

    PubMed

    Singh, K D; Hamdy, S; Aziz, Q; Thompson, D G

    1997-10-01

    We present a method for the coregistration and topographic mapping of trans-cranial magnetic stimulation (TCMS) data on surface rendered images of the cortex, derived from Magnetic Resonance Images (MRI). We describe the TCMS procedure and the methods used to locate the TCM stimulation sites in the MRI coordinate system, and the algorithms needed to depict the TCMS distribution as a pseudocolour contour map on the cortical surface. The methods are validated using TCMS data from the hand (thenar) and leg (tibialis muscle). The methods used correctly depict the expected motor representations of each of these areas and we therefore propose that this technique may be used as a functional imaging tool in the investigation of cortical function in both normals and patients.

  12. Development of a Silicon Drift Detector Array: An X-Ray Fluorescence Spectrometer for Remote Surface Mapping

    NASA Technical Reports Server (NTRS)

    Gaskin, Jessica A.; Carini, Gabriella A.; Wei, Chen; Elsner, Ronald F.; Kramer, Georgiana; De Geronimo, Gianluigi; Keister, Jeffrey W.; Zheng, Li; Ramsey, Brian D.; Rehak, Pavel; Siddons, D. Peter

    2009-01-01

    Over the past three years NASA Marshall Space Flight Center has been collaborating with Brookhaven National Laboratory to develop a modular Silicon Drift Detector (SDD) X-Ray Spectrometer (XRS) intended for fine surface mapping of the light elements of the moon. The value of fluorescence spectrometry for surface element mapping is underlined by the fact that the technique has recently been employed by three lunar orbiter missions; Kaguya, Chandrayaan-1, and Chang e. The SDD-XRS instrument we have been developing can operate at a low energy threshold (i.e. is capable of detecting Carbon), comparable energy resolution to Kaguya (<150 eV at 5.9 keV) and an order of magnitude lower power requirement, making much higher sensitivities possible. Furthermore, the intrinsic radiation resistance of the SDD makes it useful even in radiation-harsh environments such as that of Jupiter and its surrounding moons.

  13. Mapping the Potential for Eolian Surface Activity in Grasslands of the High Plains using Landsat Images

    NASA Technical Reports Server (NTRS)

    Gutmann, Ethan Dain

    2002-01-01

    There are over 100,000 square kilometers of eolian sand dunes and sand sheets in the High Plains of the central United States. These land-forms may be unstable and may reactivate again as a result of land-use, climate change, or natural climatic variability. The main goal of this thesis was to develop a model that could be used to map an estimate of future dune activity. Multi-temporal calibrated Landsats 5 Thematic Mapper (TM) and 7 Enhanced Thematic Map per Plus (ETM+) NDVI imagery were used in conjunction with the CENTURY vegetation model to correlate vegetation cover to climatic variability. This allows the creation of a predicted vegetation map which, combined with current wind and soil data, was used to create a potential sand transport map for range land in the High Plains under drought conditions.

  14. Hydrogeological Mapping and Hydrological Process Modelling for understanding the interaction of surface runoff and infiltration in a karstic catchment

    NASA Astrophysics Data System (ADS)

    Stadler, Hermann; Reszler, Christian; Komma, Jürgen; Poltnig, Walter; Strobl, Elmar; Blöschl, Günter

    2013-04-01

    This paper presents a study at the interface hydrogeology - hydrology, concerning mapping of surface runoff generation areas in a karstic catchment. The governing processes range from surface runoff with subsequent infiltration to direct infiltration and further deep percolation into different karst conduits. The aim is to identify areas with a potential of surface erosion and thus, identify the hazard of solute/contaminant input into the karst system during aestival thundershowers, which can affect water quality at springs draining the karst massif. According to hydrogeological methods the emphasis of the study are field investigations based on hydrogeological mapping and field measurements in order to gain extensive knowledge about processes and their spatial distribution in the catchment to establish a site specific Dominant Process Concept (DPC). Based on the hydrogeological map, which describes the lithological units relating to their hydrogeological classification, mapping focuses on the following attributes of the overlaying loose material/debris and soils: (i) infiltration capability, (ii) soil depth (as a measure for storage capacity), and (iii) potential surface flow length. Detailed mapping is performed in the reference area, where a variety of data are acquired, such as soil grain size distribution, soil moisture through TDR measurements at characteristic points, etc. The reference area borders both end-members of the dominant surface runoff processes as described above. Geomorphologic analyses based on a 1m resolution Laserscan assist in allocating sinks and flow accumulation paths in the catchment. By a regionalisation model, developed and calibrated based on the results in the reference areas, the process disposition is transposed onto the whole study area. In a further step, a hydrological model will be set up, where model structure and parameters are identified based on above described working steps and following the DPC. The model will be

  15. Mapping molecular conformation and orientation of polyimide surfaces for homeotropicliquid crystal alignment by nonlinear optical spectroscopy

    NASA Astrophysics Data System (ADS)

    Oh-E, Masahito; Yokoyama, Hiroshi; Kim, Doseok

    2004-05-01

    Surface-specific sum-frequency vibrational spectroscopy and second-harmonic generation were used to study the structures of polyimide (PI) surfaces for homeotropic liquid crystal (LC) alignment and the molecular orientation of LC adsobates on these surfaces. The imide ring was perpendicular to the surface with one of CO bonds protruding out of the surface and the other pointing into the bulk rather than flat on the surface. The ester CO bond in the side chain was sticking out of the surface with a tilt angle of about 45° 55° from the surface normal, indicating that the rigid side chain core was, more or less, along the surface normal. The part of alkyl chain on the top of the side chain followed the orientation of the side chain core and protruded out of the surface with some gauche defects. The cyano biphenyl LC molecules were adsorbed on the PI preferentially with the terminal cyano group facing the PI surface.

  16. Recombinant mussel adhesive protein fp-5 (MAP fp-5) as a bulk bioadhesive and surface coating material.

    PubMed

    Choi, Yoo Seong; Kang, Dong Gyun; Lim, Seonghye; Yang, Yun Jung; Kim, Chang Sup; Cha, Hyung Joon

    2011-08-01

    Mussel adhesive proteins (MAPs) attach to all types of inorganic and organic surfaces, even in wet environments. MAP of type 5 (fp-5), in particular, has been considered as a key adhesive material. However, the low availability of fp-5 has hampered its biochemical characterization and practical applications. Here, soluble recombinant fp-5 is mass-produced in Escherichia coli. Tyrosinase-modified recombinant fp-5 showed ∼1.11 MPa adhesive shear strength, which is the first report of a bulk-scale adhesive force measurement for purified recombinant of natural MAP type. Surface coatings were also performed through simple dip-coating of various objects. In addition, complex coacervate using recombinant fp-5 and hyaluronic acid was prepared as an efficient adhesive formulation, which greatly improved the bulk adhesive strength. Collectively, it is expected that this work will enhance basic understanding of mussel adhesion and that recombinant fp-5 can be successfully used as a realistic bulk-scale bioadhesive and an efficient surface coating material.

  17. Surface Ruptures and Building Damage of the 2003 Bam, Iran, Earthquake Mapped by Satellite Synthetic Aperture Radar Interferometric Correlation

    NASA Technical Reports Server (NTRS)

    Fielding, Eric J.; Talebian, M.; Rosen, P. A.; Nazari, H.; Jackson, J. A.; Ghorashi, M.; Walker, R.

    2005-01-01

    We use the interferometric correlation from Envisat synthetic aperture radar (SAR) images to map the details of the surface ruptures related to the 26 December 2003 earthquake that devastated Bam, Iran. The main strike-slip fault rupture south of the city of Bam has a series of four segments with left steps shown by a narrow line of low correlation in the coseismic interferogram. This also has a clear expression in the field because of the net extension across the fault. Just south of the city limits, the surface strain becomes distributed over a width of about 500 m, probably because of a thicker layer of soft sedimentary material.

  18. Rapid quantitative chemical mapping of surfaces with sub-2 nm resolution

    NASA Astrophysics Data System (ADS)

    Lai, Chia-Yun; Perri, Saverio; Santos, Sergio; Garcia, Ricardo; Chiesa, Matteo

    2016-05-01

    We present a theory that exploits four observables in bimodal atomic force microscopy to produce maps of the Hamaker constant H. The quantitative H maps may be employed by the broader community to directly interpret the high resolution of standard bimodal AFM images as chemical maps while simultaneously quantifying chemistry in the non-contact regime. We further provide a simple methodology to optimize a range of operational parameters for which H is in the closest agreement with the Lifshitz theory in order to (1) simplify data acquisition and (2) generalize the methodology to any set of cantilever-sample systems.We present a theory that exploits four observables in bimodal atomic force microscopy to produce maps of the Hamaker constant H. The quantitative H maps may be employed by the broader community to directly interpret the high resolution of standard bimodal AFM images as chemical maps while simultaneously quantifying chemistry in the non-contact regime. We further provide a simple methodology to optimize a range of operational parameters for which H is in the closest agreement with the Lifshitz theory in order to (1) simplify data acquisition and (2) generalize the methodology to any set of cantilever-sample systems. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr00496b

  19. Synergistic use of optical and InSAR data for urban impervious surface mapping: A case study in Hong Kong

    USGS Publications Warehouse

    Jiang, L.; Liao, M.; Lin, H.; Yang, L.

    2009-01-01

    A wide range of urban ecosystem studies, including urban hydrology, urban climate, land use planning and watershed resource management, require accurate and up‐to‐date geospatial data of urban impervious surfaces. In this study, the potential of the synergistic use of optical and InSAR data in urban impervious surface mapping at the sub‐pixel level was investigated. A case study in Hong Kong was conducted for this purpose by applying a classification and regression tree (CART) algorithm to SPOT 5 multispectral imagery and ERS‐2 SAR data. Validated by reference data derived from high‐resolution colour‐infrared (CIR) aerial photographs, our results show that the addition of InSAR feature information can improve the estimation of impervious surface percentage (ISP) in comparison with using SPOT imagery alone. The improvement is especially notable in separating urban impervious surface from the vacant land/bare ground, which has been a difficult task in ISP modelling with optical remote sensing data. In addition, the results demonstrate the potential to map urban impervious surface by using InSAR data alone. This allows frequent monitoring of world's cities located in cloud‐prone and rainy areas.

  20. Surface current patterns in the northern Adriatic extracted from high-frequency radar data using self-organizing map analysis

    NASA Astrophysics Data System (ADS)

    Mihanović, Hrvoje; Cosoli, Simone; Vilibić, Ivica; Ivanković, Damir; Dadić, Vlado; GačIć, Miroslav

    2011-08-01

    A network of high-frequency (HF) radars was installed in the northern Adriatic in the second half of 2007, aimed to measure surface currents in the framework of the North Adriatic Surface Current Mapping (NASCUM) project. This study includes a detailed analysis of current measurements from February to August 2008, a period in which three radars were simultaneously operational. Current patterns and temporal evolutions of different physical processes were extracted by using self-organizing map (SOM) analysis. The analysis focused on subtidal frequency band and extracted 12 different circulation patterns on a 4 × 3 rectangular SOM grid. The SOM was also applied on a joint data set that included contemporaneous surface wind data obtained from the operational hydrostatic mesoscale meteorological model ALADIN/HR. The strongest currents were recorded during energetic bora episodes, being recognized by several current patterns and having the characteristic downwind flow with magnitudes exceeding 35 cm/s at some grid points. Another characteristic wind, the sirocco, was represented by three current patterns, while the remaining current structures were attributed to weak winds and the residual thermohaline circulation. A strong resemblance has been found between SOM patterns extracted from HF radar data only and from combined HF radar and wind data sets, revealing the predominant wind influence to the surface circulation structures and their temporal changes in the northern Adriatic. These results show the SOM analysis being a valuable tool for extracting characteristic surface current patterns and forcing functions.

  1. Mapping land water and energy balance relations through conditional sampling of remote sensing estimates of atmospheric forcing and surface states

    NASA Astrophysics Data System (ADS)

    Farhadi, Leila; Entekhabi, Dara; Salvucci, Guido

    2016-04-01

    In this study, we develop and apply a mapping estimation capability for key unknown parameters that link the surface water and energy balance equations. The method is applied to the Gourma region in West Africa. The accuracy of the estimation method at point scale was previously examined using flux tower data. In this study, the capability is scaled to be applicable with remotely sensed data products and hence allow mapping. Parameters of the system are estimated through a process that links atmospheric forcing (precipitation and incident radiation), surface states, and unknown parameters. Based on conditional averaging of land surface temperature and moisture states, respectively, a single objective function is posed that measures moisture and temperature-dependent errors solely in terms of observed forcings and surface states. This objective function is minimized with respect to parameters to identify evapotranspiration and drainage models and estimate water and energy balance flux components. The uncertainty of the estimated parameters (and associated statistical confidence limits) is obtained through the inverse of Hessian of the objective function, which is an approximation of the covariance matrix. This calibration-free method is applied to the mesoscale region of Gourma in West Africa using multiplatform remote sensing data. The retrievals are verified against tower-flux field site data and physiographic characteristics of the region. The focus is to find the functional form of the evaporative fraction dependence on soil moisture, a key closure function for surface and subsurface heat and moisture dynamics, using remote sensing data.

  2. Mapping surface disturbance of energy-related infrastructure in southwest Wyoming--An assessment of methods

    USGS Publications Warehouse

    Germaine, Stephen S.; O'Donnell, Michael S.; Aldridge, Cameron L.; Baer, Lori; Fancher, Tammy; McBeth, Jamie; McDougal, Robert R.; Waltermire, Robert; Bowen, Zachary H.; Diffendorfer, James; Garman, Steven; Hanson, Leanne

    2012-01-01

    We evaluated how well three leading information-extraction software programs (eCognition, Feature Analyst, Feature Extraction) and manual hand digitization interpreted information from remotely sensed imagery of a visually complex gas field in Wyoming. Specifically, we compared how each mapped the area of and classified the disturbance features present on each of three remotely sensed images, including 30-meter-resolution Landsat, 10-meter-resolution SPOT (Satellite Pour l'Observation de la Terre), and 0.6-meter resolution pan-sharpened QuickBird scenes. Feature Extraction mapped the spatial area of disturbance features most accurately on the Landsat and QuickBird imagery, while hand digitization was most accurate on the SPOT imagery. Footprint non-overlap error was smallest on the Feature Analyst map of the Landsat imagery, the hand digitization map of the SPOT imagery, and the Feature Extraction map of the QuickBird imagery. When evaluating feature classification success against a set of ground-truthed control points, Feature Analyst, Feature Extraction, and hand digitization classified features with similar success on the QuickBird and SPOT imagery, while eCognition classified features poorly relative to the other methods. All maps derived from Landsat imagery classified disturbance features poorly. Using the hand digitized QuickBird data as a reference and making pixel-by-pixel comparisons, Feature Extraction classified features best overall on the QuickBird imagery, and Feature Analyst classified features best overall on the SPOT and Landsat imagery. Based on the entire suite of tasks we evaluated, Feature Extraction performed best overall on the Landsat and QuickBird imagery, while hand digitization performed best overall on the SPOT imagery, and eCognition performed worst overall on all three images. Error rates for both area measurements and feature classification were prohibitively high on Landsat imagery, while QuickBird was time and cost prohibitive for

  3. Hydrated salt minerals on Europa's Surface from the Galileo near-infrared mapping spectrometer (NIMS) investigation

    USGS Publications Warehouse

    McCord, T.B.; Hansen, G.B.; Matson, D.L.; Johnson, T.V.; Crowley, J.K.; Fanale, F.P.; Carlson, R.W.; Smythe, W.D.; Martin, P.D.; Hibbitts, C.A.; Granahan, J.C.; Ocampo, A.

    1999-01-01

    We reported evidence of heavily hydrated salt minerals present over large areas of Europa's surface from analysis of reflectance spectra returned by the Galileo mission near infrared mapping spectrometer (NIMS) [McCord et al., 1997a, b, 1998a, b]. Here we elaborate on this earlier evidence, present spatial distributions of these minerals, examine alternate water-ice interpretations, expand on our hydrated-salts interpretation, consider salt mineral stability on Europa, and discuss the implications. Extensive well-defined areas on Europa show distinct, asymmetric water-related absorption bands in the 1 to 2.5-??m region. Radiative transfer modeling of water ice involving different particle sizes and layers at Europa temperatures does not reproduce the distinctive Europa water bands. However, ice near its melting temperature, such as in terrestrial environments, does have some characteristics of the Europa spectrum. Alternatively, some classes of heavily hydrated minerals do exhibit such water bands. Among plausible materials, heavily hydrated salt minerals, such as magnesium and sodium sulfates, sodium carbonate and their mixtures, are preferred. All Europa spectral features are present in some salt minerals and a very good match to the Europa spectrum can be achieved by mixing several salt spectra. However, no single or mix of salt mineral spectra from the limited library available has so far been found to perfectly match the Europa spectrum in every detail. The material is concentrated at the lineaments and in chaotic terrain, which are technically disrupted areas on the trailing side. Since the spectrum of the material on Europa is nearly the same everywhere so-far studied, the salt or salt-mixture composition may be nearly uniform. This suggests similar sources and processes over at least a near-hemispheric scale. This would suggest that an extensive subsurface ocean containing dissolved salts is the source, and several possible mechanisms for deposit

  4. Mapping surface-atmosphere exchange by using environmental response function for both turbulent and storage eddy-covariance fluxes

    NASA Astrophysics Data System (ADS)

    Xu, K.; Metzger, S.; Desai, A. R.

    2015-12-01

    Eddy-covariance and profile measurements are widely used to develop and test parameterizations of land-atmosphere interactions in earth system models. However, a fundamental challenge for these comparisons lies in the scale mismatch: Observations represent temporally varying and small source areas (100-101 km2), while simulations produce temporally regular, regional-scale grids (102-103 km2). The environmental response function (ERF) method provides a promising link through unveiling the regional flux field underlying the observed surface-atmosphere exchange. This is achieved by relating sub-hourly turbulent fluxes to meteorological forcings and surface properties, and utilizing the resulting relationships for spatio-temporal mapping. However, a new challenge arises: At sub-hourly time scales, surface-atmosphere exchange is rarely resolved completely by the turbulent flux alone. Specifically in the case of taller towers, storage beneath the turbulent flux measurement height can comprise a substantial amount of the actual surface-atmosphere exchange. Here, we show how temporally resolved maps of heat, water and carbon net ecosystem exchange can be produced by applying ERF to turbulent and storage flux. For this purpose, eddy-covariance and profile observations from the 447 m tall AmeriFlux Park Falls WLEF tower in Wisconsin, USA are used. To construct the coupled ERF, eddy-covariance and profile observations are related to surface properties using a flux and a scalar concentration source-area model, respectively. Through superposition, we demonstrate enhanced performance in mapping observed net ecosystem exchange, and the potential to also diagnose advective contributions. These advances promise significant improvements for model-data comparison, assimilation and model building.

  5. MODELING THE ANOMALY OF SURFACE NUMBER DENSITIES OF GALAXIES ON THE GALACTIC EXTINCTION MAP DUE TO THEIR FIR EMISSION CONTAMINATION

    SciTech Connect

    Kashiwagi, Toshiya; Suto, Yasushi; Taruya, Atsushi; Yahata, Kazuhiro; Kayo, Issha; Nishimichi, Takahiro

    2015-02-01

    The most widely used Galactic extinction map is constructed assuming that the observed far-infrared (FIR) fluxes come entirely from Galactic dust. According to the earlier suggestion by Yahata et al., we consider how FIR emission of galaxies affects the SFD map. We first compute the surface number density of Sloan Digital Sky Survey (SDSS) DR7 galaxies as a function of the r-band extinction, A {sub r,} {sub SFD}. We confirm that the surface densities of those galaxies positively correlate with A {sub r,} {sub SFD} for A {sub r,} {sub SFD} < 0.1, as first discovered by Yahata et al. for SDSS DR4 galaxies. Next we construct an analytical model to compute the surface density of galaxies, taking into account the contamination of their FIR emission. We adopt a log-normal probability distribution for the ratio of 100 μm and r-band luminosities of each galaxy, y ≡ (νL){sub 100} {sub μm}/(νL) {sub r}. Then we search for the mean and rms values of y that fit the observed anomaly, using the analytical model. The required values to reproduce the anomaly are roughly consistent with those measured from the stacking analysis of SDSS galaxies. Due to the limitation of our statistical modeling, we are not yet able to remove the FIR contamination of galaxies from the extinction map. Nevertheless, the agreement with the model prediction suggests that the FIR emission of galaxies is mainly responsible for the observed anomaly. Whereas the corresponding systematic error in the Galactic extinction map is 0.1-1 mmag, it is directly correlated with galaxy clustering and thus needs to be carefully examined in precision cosmology.

  6. Effects of new MODIS land cover map replacement in a regional climate model on surface temperature and humidity

    NASA Astrophysics Data System (ADS)

    Yucel, I.

    This study investigates the extent to which utilizing 1-km new the Moderate-resolution Imaging-Spectroradiometer (MODIS) land use data in the Pennsylvania State University/NCAR's MM5 coupled with Oregon State University (OSU) provides an improved regional diagnosis of near-surface atmospheric state variables as well as characteristics of the planetary boundary layer (PBL). Those variables are strongly influenced by the energy, matter and momentum exchange between the land surface and the atmosphere. MODIS data provides not only a detailed spatial distribution of vegetation, but also a delineation between water bodies and land surface for MM5 high-resolution applications. Advances in remote sensing technology allow MODIS to collect higher-quality data than previous sensors, yielding the most detailed land cover classification maps to date. The new maps are better because the quality of MODIS data is much higher than the National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiometer (AVHRR). The default 25-category United States Geological Survey (USGS) land cover classification in MM5 was produced using data acquired in from 1992-1993 by AVHRR. Parameter sets of 17-category MODIS land use dataset are determined by making close match between MODIS, USGS and SIB categories to use in OSU land-surface model. 1-km Land-Water Mask (LWM) data is also derived from this new data as an input to MM5. When the MM5 horizontal grid increment is larger than 1-km (4-km and 12-km in current study), the dominant vegetation type in each grid box is selected to represent the ``grid level'' vegetation characteristics. The MODIS data consider the influence of detailed picture of the distribution of Earth's ecosystems in the surface energy and water budget and hence the evolution of the boundary layer. The impact on the near-surface temperature and humidity is given by making comparison between model and observations at selected land surface types.

  7. Mapping Porosity Structure Offshore Torrey Pines State Natural Reserve and Del Mar, California Using a Surface Towed EM System

    NASA Astrophysics Data System (ADS)

    Martin, Thomas Patrick

    Controlled source electromagnetic methods have been used in exploration of the offshore environment for over 50 years to map the resistivity structure of the earth. Developments in both instrumentation and computational power have lead to many advancements that have led to discoveries and insights about the subsurface. One of these advancements has been the development of towed EM acquisition systems. One system the Marine EM Lab at Scripps Institution of Oceanography has developed is a shallow water system, named Porpoise, can be used in water depths as shallow as 5m. In May of 2014, a one day field test of this new shallow water acquisition system took place offshore of Del Mar and Torrey Pines State Natural Reserve, California. The data from this field test corresponds with previous interpretations of paleochannels directly offshore modern day San Dieguito and Soledad Valley river outflows. With resistivity data, it is possible to indirectly map porosity in the near surface and to map geological features. The data dense and economical operation of the Porpoise acquisition system can be used to map resistivity and indirectly porosity in a variety of shallow water marine environments. This field test proves the viability and limitations of the Porpoise system.

  8. Map showing general chemical quality of surface water in the Kaiparowits coal-basin area, Utah

    USGS Publications Warehouse

    Price, Don

    1979-01-01

    This is one of a series of maps that describe the geology and related natural resources in the Kaiparowits coal-basin area, Utah Published sources of water-quality data used in the preparation of this map included Iorns, Hembree, Phoenix, and Oakland (1964), Goode (1966, 1969), U.S. Bureau of Land Management (1976), and U.S. Geological Survey (1961-75). Sources of unpublished data include the U.S. Bureau of Reclamation and the Southeastern Utah Association of Governments. Some of the unpublished data was provided by Vaughn Hansen Associates of Salt Lake City, Utah, whose assistance is gratefully acknowledged.

  9. Integration Over Curves and Surfaces Defined by the Closest Point Mapping

    DTIC Science & Technology

    2015-04-01

    paper provides simple formulations for integrating over manifolds of codimensions one, or two in R3 , when the manifolds are described by functions...level set. Now suppose that ∂Ω is a smooth hypersurface in R3 and assume that x is suffi- ciently close to Ω so that the closest point mapping x∗ = P∂Ω(x...closest point mapping ∂P∂Ω ∂x ; namely, ˆ ∂Ω v(x(s))ds = ˆ R3 v(P∂Ω(x))δ(d∂Ω(x)) 2∏ j=1 σj(x)dx. To motivate the new approach using singular values, we

  10. Method for detecting surface motions and mapping small terrestrial or planetary surface deformations with synthetic aperture radar

    NASA Technical Reports Server (NTRS)

    Gabriel, Andrew K. (Inventor); Goldstein, Richard M. (Inventor); Zebker, Howard A. (Inventor)

    1990-01-01

    A technique based on synthetic aperture radar (SAR) interferometry is used to measure very small (1 cm or less) surface deformations with good resolution (10 m) over large areas (50 km). It can be used for accurate measurements of many geophysical phenomena, including swelling and buckling in fault zones, residual, vertical and lateral displacements from seismic events, and prevolcanic swelling. Two SAR images are made of a scene by two spaced antennas and a difference interferogram of the scene is made. After unwrapping phases of pixels of the difference interferogram, surface motion or deformation changes of the surface are observed. A second interferogram of the same scene is made from a different pair of images, at least one of which is made after some elapsed time. The second interferogram is then compared with the first interferogram to detect changes in line of sight position of pixels. By resolving line of sight observations into their vector components in other sets of interferograms along at least one other direction, lateral motions may be recovered in their entirety. Since in general, the SAR images are made from flight tracks that are separated, it is not possible to distinguish surface changes from the parallax caused by topography. However, a third image may be used to remove the topography and leave only the surface changes.

  11. Molecular-scale investigations of structures and surface charge distribution of surfactant aggregates by three-dimensional force mapping

    SciTech Connect

    Suzuki, Kazuhiro; Oyabu, Noriaki; Matsushige, Kazumi; Yamada, Hirofumi; Kobayashi, Kei

    2014-02-07

    Surface charges on nanoscale structures in liquids, such as biomolecules and nano-micelles, play an essentially important role in their structural stability as well as their chemical activities. These structures interact with each other through electric double layers (EDLs) formed by the counter ions in electrolyte solution. Although static-mode atomic force microscopy (AFM) including colloidal-probe AFM is a powerful technique for surface charge density measurements and EDL analysis on a submicron scale in liquids, precise surface charge density analysis with single-nanometer resolution has not been made because of its limitation of the resolution and the detection sensitivity. Here we demonstrate molecular-scale surface charge measurements of self-assembled micellar structures, molecular hemicylinders of sodium dodecyl sulfate (SDS), by three-dimensional (3D) force mapping based on frequency modulation AFM. The SDS hemicylindrical structures with a diameter of 4.8 nm on a graphite surface were clearly imaged. We have succeeded in visualizing 3D EDL forces on the SDS hemicylinder surfaces and obtaining the molecular-scale charge density for the first time. The results showed that the surface charge on the trench regions between the hemicylinders was much smaller than that on the hemicylinder tops. The method can be applied to a wide variety of local charge distribution studies, such as spatial charge variation on a single protein molecule.

  12. Usefulness of ventricular endocardial electric reconstruction from body surface potential maps to noninvasively localize ventricular ectopic activity in patients

    NASA Astrophysics Data System (ADS)

    Lai, Dakun; Sun, Jian; Li, Yigang; He, Bin

    2013-06-01

    As radio frequency (RF) catheter ablation becomes increasingly prevalent in the management of ventricular arrhythmia in patients, an accurate and rapid determination of the arrhythmogenic site is of important clinical interest. The aim of this study was to test the hypothesis that the inversely reconstructed ventricular endocardial current density distribution from body surface potential maps (BSPMs) can localize the regions critical for maintenance of a ventricular ectopic activity. Patients with isolated and monomorphic premature ventricular contractions (PVCs) were investigated by noninvasive BSPMs and subsequent invasive catheter mapping and ablation. Equivalent current density (CD) reconstruction (CDR) during symptomatic PVCs was obtained on the endocardial ventricular surface in six patients (four men, two women, years 23-77), and the origin of the spontaneous ectopic activity was localized at the location of the maximum CD value. Compared with the last (successful) ablation site (LAS), the mean and standard deviation of localization error of the CDR approach were 13.8 and 1.3 mm, respectively. In comparison, the distance between the LASs and the estimated locations of an equivalent single moving dipole in the heart was 25.5 ± 5.5 mm. The obtained CD distribution of activated sources extending from the catheter ablation site also showed a high consistency with the invasively recorded electroanatomical maps. The noninvasively reconstructed endocardial CD distribution is suitable to predict a region of interest containing or close to arrhythmia source, which may have the potential to guide RF catheter ablation.

  13. Use of a satellite-derived land cover map to estimate transport of radiocaesium to surface waters.

    PubMed

    Smith, J T; Howard, D C; Wright, S M; Naylor, C; Brookes, A M; Hilton, J; Howard, B J

    1998-01-08

    During the weeks to months after the deposition of radioactive fallout, the initial concentration of radioactivity in rivers and lakes declines as a result of flushing and removal to bottom sediments. In the long-term, however, radioactivity in the water body can remain at significant levels as a result of secondary contamination processes. In particular, it is known that soils contaminated by long-lived radionuclides such as 137Cs and 90Sr provide a significant source to surface waters over a period of years after fallout. Using The Land Cover Map of Great Britain, a satellite-derived land cover map as a surrogate indicator of soil type, we have related catchment land cover type to long-term 137Cs activity concentrations in 27 lakes in Cumbria, UK. The study has shown that satellite-derived maps could be used to indicate areas vulnerable to high long-term 137Cs transport to surface waters in the event of a nuclear accident. In these Cumbrian lakes, it appears that residual 137Cs levels are determined by transfers of 137Cs from contaminated catchments rather than within-lake processes. Only three of the cover types, open shrub moor, bog and dense shrub moor, as identified by the satellite, are needed to explain over 90% of the variation in long-term 137Cs activity concentrations in the lakes, and these have been shown to correlate spatially with occurrence of organic soils.

  14. Mapping of Proteomic Composition on the Surfaces of Bacillus spores by Atomic Force Microscopy-based Immunolabeling

    SciTech Connect

    Plomp, M; Malkin, A J

    2008-06-02

    Atomic force microscopy provides a unique capability to image high-resolution architecture and structural dynamics of pathogens (e.g. viruses, bacteria and bacterial spores) at near molecular resolution in native conditions. Further development of atomic force microscopy in order to enable the correlation of pathogen protein surface structures with specific gene products is essential to understand the mechanisms of the pathogen life cycle. We have applied an AFM-based immunolabeling technique for the proteomic mapping of macromolecular structures through the visualization of the binding of antibodies, conjugated with nanogold particles, to specific epitopes on Bacillus spore surfaces. This information is generated while simultaneously acquiring the surface morphology of the pathogen. The immunospecificity of this labeling method was established through the utilization of specific polyclonal and monoclonal antibodies that target spore coat and exosporium epitopes of Bacillus atrophaeus and Bacillus anthracis spores.

  15. Reciprocal space XRD mapping with varied incident angle as a probe of structure variation within surface depth

    SciTech Connect

    Yang, Qiguang; Williams, Frances; Zhao, Xin; Reece, Charles E.; Krishnan, Mahadevan

    2013-09-01

    In this study, we used a differential-depth X-Ray diffraction Reciprocal Spacing Mapping (XRD RSM) technique to investigate the crystal quality of a variety of SRF-relevant Nb film and bulk materials. By choosing different X-ray probing depths, the RSM study successfully revealed evolution the of materials microstructure after different materials processes, such as energetic condensation or surface polishing. The RSM data clearly measured the materials crystal quality at different thickness. Through a novel differential-depth RSM technique, this study found: I. for a heteroepitaxy Nb film Nb(100)/MgO(100), the film thickening process, via a cathodic arc-discharge Nb ion deposition, created a near-perfect single crystal Nb on the surfaces top-layer; II. for a mechanically polished single-crystal bulk Nb material, the microstructure on the top surface layer is more disordered than that in-grain.

  16. Mapping of proteomic composition on the surfaces of bacillus spores by atomic force microscopy-based immunolabeling.

    PubMed

    Plomp, Marco; Malkin, Alexander J

    2009-01-06

    Atomic force microscopy (AFM) provides a unique capability to image high-resolution architecture and structural dynamics of pathogens (e.g., viruses, bacteria, and bacterial spores) at near-molecular resolution in native conditions. Further development of atomic force microscopy to enable the correlation of pathogen protein surface structures with specific gene products is essential to understand the mechanisms of the pathogen life cycle. We applied an AFM-based immunolabeling technique for the proteomic mapping of macromolecular structures through the visualization of the binding of antibodies, conjugated with nanogold particles, to specific epitopes on Bacillus spore surfaces. This information is generated while simultaneously acquiring the surface morphology of the pathogen. The immunospecificity of this labeling method was established through the utilization of specific polyclonal and monoclonal antibodies that target spore coat and exosporium epitopes of Bacillus atrophaeus and Bacillus anthracis spores.

  17. Feasibility of correlation mapping optical coherence tomography (cmOCT) for anti-spoof sub-surface fingerprinting.

    PubMed

    Zam, Azhar; Dsouza, Roshan; Subhash, Hrebesh M; O'Connell, Marie-Louise; Enfield, Joey; Larin, Kirill; Leahy, Martin J

    2013-09-01

    We propose the use of correlation mapping optical coherence tomography (cmOCT) to deliver additional biometrics associated with the finger that could complement existing fingerprint technology for law enforcement applications. The current study extends the existing fingerprint paradigm by measuring additional biometrics associated with sub-surface finger tissue such as sub-surface fingerprints, sweat glands, and the pattern of the capillary bed to yield a user-friendly cost effective and anti-spoof multi-mode biometric solution associated with the finger. To our knowledge no other method has been able to capture sub-surface fingerprint, papillary pattern and horizontal vessel pattern in a single scan or to show the correspondence between these patterns in live adult human fingertip. Unlike many current technologies this approach incorporates 'liveness' testing by default. The ultimate output is a biometric module which is difficult to defeat and complements fingerprint scanners that currently are used in border control and law enforcement applications.

  18. Downscaling of Land Surface Temperature Maps in the Texas High Plains with TsHARP Method

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High spatial resolution daily evapotranspiration (ET) maps would significantly improve assessing crop water requirements in arid and semi-arid regions of the world such as Texas High Plains (THP) where water demand exceeds supply for irrigation. Remote sensing-based models that use energy balance eq...

  19. Surface Energy Balance Based Evapotranspiration Mapping in the Texas High Plains.

    PubMed

    Gowda, Prasanna H; Chávez, José L; Howell, Terry A; Marek, Thomas H; New, Leon L

    2008-08-28

    Agriculture on the Texas High Plains (THP) uses approximately 89% of groundwater withdrawals from the Ogallala Aquifer. Consequently, groundwater levels are declining faster than the recharge rate. Therefore, efficient agricultural water use is essential for economic viability and sustainability of the THP. Accurate regional evapotranspiration (ET) maps would provide valuable information on actual crop water use. In this study, METRIC (Mapping Evapotranspiration at High Resolution using Internalized Calibration), a remote sensing based ET algorithm, was evaluated for mapping ET in the THP. Two Landsat 5 Thematic Mapper images acquired on 27 June (DOY 178) and 29 July (DOY 210) 2005 were used for this purpose. The performance of the ET model was evaluated by comparing the predicted daily ET with values derived from soil moisture budget at four commercial agricultural fields. Daily ET estimates resulted with a prediction error of 12.7±8.1% (mean bias error ± root mean square error) on DOY 178 and -4.7±9.4% on DOY 210 when compared with ET derived from measured soil moisture through the soil water balance. These results are good considering the prevailing advective conditions in the THP. METRIC have the potential to be used for mapping regional ET in the THP region. However, more evaluation is needed under different agroclimatological conditions.

  20. Surface Energy Balance Based Evapotranspiration Mapping in the Texas High Plains

    PubMed Central

    Gowda, Prasanna H.; Chávez, José L.; Howell, Terry A.; Marek, Thomas H.; New, Leon L.

    2008-01-01

    Agriculture on the Texas High Plains (THP) uses approximately 89% of groundwater withdrawals from the Ogallala Aquifer. Consequently, groundwater levels are declining faster than the recharge rate. Therefore, efficient agricultural water use is essential for economic viability and sustainability of the THP. Accurate regional evapotranspiration (ET) maps would provide valuable information on actual crop water use. In this study, METRIC (Mapping Evapotranspiration at High Resolution using Internalized Calibration), a remote sensing based ET algorithm, was evaluated for mapping ET in the THP. Two Landsat 5 Thematic Mapper images acquired on 27 June (DOY 178) and 29 July (DOY 210) 2005 were used for this purpose. The performance of the ET model was evaluated by comparing the predicted daily ET with values derived from soil moisture budget at four commercial agricultural fields. Daily ET estimates resulted with a prediction error of 12.7±8.1% (mean bias error ± root mean square error) on DOY 178 and -4.7±9.4% on DOY 210 when compared with ET derived from measured soil moisture through the soil water balance. These results are good considering the prevailing advective conditions in the THP. METRIC have the potential to be used for mapping regional ET in the THP region. However, more evaluation is needed under different agroclimatological conditions. PMID:27873809

  1. Rapid Semi-Quantitative Surface Mapping of Airborne-Dispersed Chemicals Using Mass Spectrometry

    EPA Science Inventory

    Chemicals can be dispersed accidentally, deliberately, or by weather-related events. Rapid mapping of contaminant distributions is necessary to assess exposure risks and to plan remediation, when needed. Ten pulverized aspirin or NoDozTM tablets containing caffeine wer...

  2. Developed Design for Humeral Head Replacement Using 3D Surface Mapping

    NASA Astrophysics Data System (ADS)

    Salah, H. R.

    2014-12-01

    Assessment of dimensional and geometrical data on the humeral head replacement (HHR) objects is essential for solving the relevant designing problems in the physics of reverse engineering (RE). In this work, 2D-assessment for human humerus was performed using the computed tomography (CT) technique within the RE plan, after which the 2D images of humeral objects were converted into 3D images. The conversion was successful and indicated a clear difference in the 2D and 3D estimates of sizes and geometry of the humerus. The authors have analyzed and confirmed experimentally the statistical information on the relevant anatomical objects. The results of finite-element simulation of the compressive stresses affecting the geometry of 3D surface mapping were analyzed using SolidWorks software. For developing the biomechanical design of an HHR object suitable biomaterials were selected, and different metal-based biomaterials are discussed as applied at various loads. New methodology is presented for the size estimation of humeral head - both anatomical and artificial - in 3D-shape. A detailed interpretation is given for the results of CT D-measurements. Izmēru un ģeometrisko datu novērtējums, kas attiecas uz pleca kaula galviņas nomaiņas (PKGN) objektiem, nepieciešams, lai risinātu virkni reversīvās inženierijas (RI) problēmu. Šajā darbā cilvēka pleca kaula galviņas divdimensiju novērtējums tika veikts ar datortomogrāfijas palīdzību (RI) ietvaros, un pēc tam objekta divdimensiju attēlojums tika pārveidots trīsdimensiju. Pārveidojums bija sekmīgs, parādot pleca kaula galviņas izmēru un ģeometrijas atšķirības starp 2D un 3D novērtējumiem. Autori izanalizēja un eksperimentāli apstiprināja statistisko informāciju pēc dotā veida anatomiskiem objektiem. Saspiešanas sasprindzinājumi, kuri ietekmē trīsdimensiju virsmas attēlojuma ģeometriju, tika analizēti ar gala-elementu simulācijas metodi, lietojot programmu Solid

  3. Potential of EnMAP spaceborne imaging spectroscopy for the prediction of common surface soil properties and expected accuracy

    NASA Astrophysics Data System (ADS)

    Chabrillat, Sabine; Foerster, Saskia; Steinberg, Andreas; Stevens, Antoine; Segl, Karl

    2016-04-01

    There is a renewed awareness of the finite nature of the world's soil resources, growing concern about soil security, and significant uncertainties about the carrying capacity of the planet. As a consequence, soil scientists are being challenged to provide regular assessments of soil conditions from local through to global scales. However, only a few countries have the necessary survey and monitoring programs to meet these new needs and existing global data sets are out-of-date. A particular issue is the clear demand for a new area-wide regional to global coverage with accurate, up-to-date, and spatially referenced soil information as expressed by the modeling scientific community, farmers and land users, and policy and decision makers. Soil spectroscopy from remote sensing observations based on studies from the laboratory scale to the airborne scale has been shown to be a proven method for the quantitative prediction of key soil surface properties in local areas for exposed soils in appropriate surface conditions such as low vegetation cover and low water content. With the upcoming launch of the next generation of hyperspectral satellite sensors in the next 3 to 5 years (EnMAP, HISUI, PRISMA, SHALOM), a great potential for the global mapping and monitoring of soil properties is appearing. Nevertheless, the capabilities to extend the soil properties current spectral modeling from local to regional scales are still to be demonstrated using robust methods. In particular, three central questions are at the forefront of research nowadays: a) methodological developments toward improved algorithms and operational tools for the extraction of soil properties, b) up scaling from the laboratory into space domain, and c) demonstration of the potential of upcoming satellite systems and expected accuracy of soil maps. In this study, airborne imaging spectroscopy data from several test sites are used to simulate EnMAP satellite images at 30 m scale. Then, different soil

  4. Multivariate Tensor-based Morphometry on Surfaces: Application to Mapping Ventricular Abnormalities in HIV/AIDS

    PubMed Central

    Wang, Yalin; Zhang, Jie; Gutman, Boris; Chan, Tony F.; Becker, James T.; Aizenstein, Howard J.; Lopez, Oscar L.; Tamburo, Robert J.; Toga, Arthur W.; Thompson, Paul M.

    2010-01-01

    Here we developed a new method, called multivariate tensor-based surface morphometry (TBM), and applied it to study lateral ventricular surface differences associated with HIV/AIDS. Using concepts from differential geometry and the theory of differential forms, we created mathematical structures known as holomorphic one-forms, to obtain an efficient and accurate conformal parameterization of the lateral ventricular surfaces in the brain. The new meshing approach also provides a natural way to register anatomical surfaces across subjects, and improves on prior methods as it handles surfaces that branch and join at complex 3D junctions. To analyze anatomical differences, we computed new statistics from the Riemannian surface metrics - these retain multivariate information on local surface geometry. We applied this framework to analyze lateral ventricular surface morphometry in 3D MRI data from 11 subjects with HIV/AIDS and 8 healthy controls. Our method detected a 3D profile of surface abnormalities even in this small sample. Multivariate statistics on the local tensors gave better effect sizes for detecting group differences, relative to other TBM-based methods including analysis of the Jacobian determinant, the largest and smallest eigenvalues of the surface metric, and the pair of eigenvalues of the Jacobian matrix. The resulting analysis pipeline may improve the power of surface-based morphometry studies of the brain. PMID:19900560

  5. Expert system designed to assist in the interpretation and evaluation of thoracic surface maps produced by high-resolution electrocardiography

    SciTech Connect

    Johnson, J.K.

    1988-01-01

    An expert system is an artificial intelligence program that relies on a knowledge base composed of information derived from an expert and is designed to perform a difficult task. The system is usually domain specific and provides an interactive consultation with the user in problem solving. High-resolution electrocardiography is a technique for acquiring information about the heart's electrical activity with the use of multilead electrodes. Thoracic surface maps are presented at precise intervals during the depolarization/repolarization stages of a heartbeat. Cardiologists have determined methods for relating the thoracic maps to the actual tissue condition of the heart giving a basis for diagnoses. This work shows the anatomy of the heart, techniques for measuring that activity, and in detail, the techniques used with High Resolution Electrocardiography. The field of artificial intelligence is explored with an emphasis on expert systems. An expert system developed to diagnose the HRE record is presented.

  6. Potentiometric-surface map of water in the Judith River Formation in the Northern Great Plains area of Montana

    USGS Publications Warehouse

    Levings, Gary W.

    1982-01-01

    The potentiometric surface of the Judith River Formation is mapped at a scale of 1:1,000,000. The map is one of a series produced as part of a regional study of aquifers of Cenozoic and Mesozoic age in the northern Great Plains of Montana. The contour interval is 200 feet. Water in the Judith River Formation occurs under water-table and artesian conditions. The direction of regional ground-water movement is from west to east. Water is discharged from the Judith River Formation to the Milk River from near Havre, Montana, to Malta and to the Missouri River south of the Bearpaw and Little Rocky Mountains. The average discharge from 236 wells is about 10 gallons per minute, and the specific capacity of 186 wells averages 0.66 gallon per minute per foot of drawdown. (USGS)

  7. Statistical mapping of zones of focused groundwater/surface-water exchange using fiber-optic distributed temperature sensing

    USGS Publications Warehouse

    Mwakanyamale, Kisa; Day-Lewis, Frederick D.; Slater, Lee D.

    2013-01-01

    Fiber-optic distributed temperature sensing (FO-DTS) increasingly is used to map zones of focused groundwater/surface-water exchange (GWSWE). Previous studies of GWSWE using FO-DTS involved identification of zones of focused GWSWE based on arbitrary cutoffs of FO-DTS time-series statistics (e.g., variance, cross-correlation between temperature and stage, or spectral power). New approaches are needed to extract more quantitative information from large, complex FO-DTS data sets while concurrently providing an assessment of uncertainty associated with mapping zones of focused GSWSE. Toward this end, we present a strategy combining discriminant analysis (DA) and spectral analysis (SA). We demonstrate the approach using field experimental data from a reach of the Columbia River adjacent to the Hanford 300 Area site. Results of the combined SA/DA approach are shown to be superior to previous results from qualitative interpretation of FO-DTS spectra alone.

  8. Mapping paddy rice planting areas through time series analysis of MODIS land surface temperature and vegetation index data

    NASA Astrophysics Data System (ADS)

    Zhang, Geli; Xiao, Xiangming; Dong, Jinwei; Kou, Weili; Jin, Cui; Qin, Yuanwei; Zhou, Yuting; Wang, Jie; Menarguez, Michael Angelo; Biradar, Chandrashekhar

    2015-08-01

    Knowledge of the area and spatial distribution of paddy rice is important for assessment of food security, management of water resources, and estimation of greenhouse gas (methane) emissions. Paddy rice agriculture has expanded rapidly in northeastern China in the last decade, but there are no updated maps of paddy rice fields in the region. Existing algorithms for identifying paddy rice fields are based on the unique physical features of paddy rice during the flooding and transplanting phases and use vegetation indices that are sensitive to the dynamics of the canopy and surface water content. However, the flooding phenomena in high latitude area could also be from spring snowmelt flooding. We used land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor to determine the temporal window of flooding and rice transplantation over a year to improve the existing phenology-based approach. Other land cover types (e.g., evergreen vegetation, permanent water bodies, and sparse vegetation) with potential influences on paddy rice identification were removed (masked out) due to their different temporal profiles. The accuracy assessment using high-resolution images showed that the resultant MODIS-derived paddy rice map of northeastern China in 2010 had a high accuracy (producer and user accuracies of 92% and 96%, respectively). The MODIS-based map also had a comparable accuracy to the 2010 Landsat-based National Land Cover Dataset (NLCD) of China in terms of both area and spatial pattern. This study demonstrated that our improved algorithm by using both thermal and optical MODIS data, provides a robust, simple and automated approach to identify and map paddy rice fields in temperate and cold temperate zones, the northern frontier of rice planting.

  9. Mapping paddy rice planting areas through time series analysis of MODIS land surface temperature and vegetation index data

    PubMed Central

    Zhang, Geli; Xiao, Xiangming; Dong, Jinwei; Kou, Weili; Jin, Cui; Qin, Yuanwei; Zhou, Yuting; Wang, Jie; Menarguez, Michael Angelo; Biradar, Chandrashekhar

    2016-01-01

    Knowledge of the area and spatial distribution of paddy rice is important for assessment of food security, management of water resources, and estimation of greenhouse gas (methane) emissions. Paddy rice agriculture has expanded rapidly in northeastern China in the last decade, but there are no updated maps of paddy rice fields in the region. Existing algorithms for identifying paddy rice fields are based on the unique physical features of paddy rice during the flooding and transplanting phases and use vegetation indices that are sensitive to the dynamics of the canopy and surface water content. However, the flooding phenomena in high latitude area could also be from spring snowmelt flooding. We used land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor to determine the temporal window of flooding and rice transplantation over a year to improve the existing phenology-based approach. Other land cover types (e.g., evergreen vegetation, permanent water bodies, and sparse vegetation) with potential influences on paddy rice identification were removed (masked out) due to their different temporal profiles. The accuracy assessment using high-resolution images showed that the resultant MODIS-derived paddy rice map of northeastern China in 2010 had a high accuracy (producer and user accuracies of 92% and 96%, respectively). The MODIS-based map also had a comparable accuracy to the 2010 Landsat-based National Land Cover Dataset (NLCD) of China in terms of both area and spatial pattern. This study demonstrated that our improved algorithm by using both thermal and optical MODIS data, provides a robust, simple and automated approach to identify and map paddy rice fields in temperate and cold temperate zones, the northern frontier of rice planting. PMID:27667901

  10. Estimation and Mapping of the Winter-Time Increase of the Water Ice Amount in the Martian Surface Soil Based on the TES TI Seasonal Variations Analysis

    NASA Astrophysics Data System (ADS)

    Kuzmin, R. O.; Zabalueva, E. V.; Christensen, P. R.

    2008-03-01

    In the work we presents the preliminary results of new method for estimation and global mapping of the winter-time increase of the water ice in the martian surface soil based on the TES TI data analysis.

  11. C-band RISAT-1 imagery for geospatial mapping of cryospheric surface features in the Antarctic environment

    NASA Astrophysics Data System (ADS)

    Jawak, Shridhar D.; Panditrao, Satej N.; Luis, Alvarinho J.

    2016-05-01

    Cryospheric surface feature classification is one of the widely used applications in the field of polar remote sensing. Precise surface feature maps derived from remotely sensed imageries are the major requirement for many geoscientific applications in polar regions. The present study explores the capabilities of C-band dual polarimetric (HH & HV) SAR imagery from Indian Radar Imaging Satellite (RISAT-1) for land cryospheric surface feature mapping. The study areas selected for the present task were Larsemann Hills and Schirmacher Oasis, East Antarctica. RISAT-1 Fine Resolution STRIPMAP (FRS-1) mode data with 3-m spatial resolution was used in the present research attempt. In order to provide additional context to the amount of information in dual polarized RISAT-1 SAR data, a band HH+HV was introduced to make use of the original two polarizations. In addition to the data calibration, transformed divergence (TD) procedure was performed for class separability analysis to evaluate the quality of the statistics before image classification. For most of the class pairs the TD values were comparable, which indicated that the classes have good separability. Fuzzy and Artificial Neural Network classifiers were implemented and accuracy was checked. Nonparametric classifier Support Vector Machine (SVM) was also used to classify RISAT-1 data with an optimized polarization combination into three land-cover classes consisting of sea ice/snow/ice, rocks/landmass, and lakes/waterbodies. This study demonstrates that C-band FRS1 image mode data from the RISAT-1 mission can be exploited to identify, map and monitor land cover features in the polar regions, even during dark winter period. For better landcover classification and analysis, hybrid polarimetric data (cFRS-1 mode) from RISAT-1, which incorporates phase information, unlike the dual-pol linear (HH, HV) can be used for obtaining better polarization signatures.

  12. Including Faults Detected By Near-Surface Seismic Methods in the USGS National Seismic Hazard Maps - Some Restrictions Apply

    NASA Astrophysics Data System (ADS)

    Williams, R. A.; Haller, K. M.

    2014-12-01

    Every 6 years, the USGS updates the National Seismic Hazard Maps (new version released July 2014) that are intended to help society reduce risk from earthquakes. These maps affect hundreds of billions of dollars in construction costs each year as they are used to develop seismic-design criteria of buildings, bridges, highways, railroads, and provide data for risk assessment that help determine insurance rates. Seismic source characterization, an essential component of hazard model development, ranges from detailed trench excavations across faults at the ground surface to less detailed analysis of broad regions defined mainly on the basis of historical seismicity. Though it is a priority for the USGS to discover new Quaternary fault sources, the discovered faults only become a part of the hazard model if there are corresponding constraints on their geometry (length and depth extent) and slip-rate (or recurrence interval). When combined with fault geometry and slip-rate constraints, near-surface seismic studies that detect young (Quaternary) faults have become important parts of the hazard source model. Examples of seismic imaging studies with significant hazard impact include the Southern Whidbey Island fault, Washington; Santa Monica fault, San Andreas fault, and Palos Verdes fault zone, California; and Commerce fault, Missouri. There are many more faults in the hazard model in the western U.S. than in the expansive region east of the Rocky Mountains due to the higher rate of tectonic deformation, frequent surface-rupturing earthquakes and, in some cases, lower erosion rates. However, the recent increase in earthquakes in the central U.S. has revealed previously unknown faults for which we need additional constraints before we can include them in the seismic hazard maps. Some of these new faults may be opportunities for seismic imaging studies to provide basic data on location, dip, style of faulting, and recurrence.

  13. Scanning Electron Microscope Mapping System Developed for Detecting Surface Defects in Fatigue Specimens

    NASA Technical Reports Server (NTRS)

    Bonacuse, Peter J.; Kantzos, Peter T.

    2002-01-01

    An automated two-degree-of-freedom specimen positioning stage has been developed at the NASA Glenn Research Center to map and monitor defects in fatigue specimens. This system expedites the examination of the entire gauge section of fatigue specimens so that defects can be found using scanning electron microscopy (SEM). Translation and rotation stages are driven by microprocessor-based controllers that are, in turn, interfaced to a computer running custom-designed software. This system is currently being used to find and record the location of ceramic inclusions in powder metallurgy materials. The mapped inclusions are periodically examined during interrupted fatigue experiments. The number of cycles to initiate cracks from these inclusions and the rate of growth of initiated cracks can then be quantified. This information is necessary to quantify the effect of this type of defect on the durability of powder metallurgy materials. This system was developed with support of the Ultra Safe program.

  14. Mapping wetlands and surface water in the Prairie Pothole Region of North America: Chapter 16

    USGS Publications Warehouse

    Rover, Jennifer R.; Mushet, David M.

    2015-01-01

    The Prairie Pothole Region (PPR) is one of the most highly productive wetland regions in the world. Prairie Pothole wetlands serve as a primary feeding and breeding habitat for more than one-half of North America’s waterfowl population, as well as a variety of songbirds, waterbirds, shorebirds, and other wildlife. During the last century, extensive land conversions from grassland with wetlands to cultivated cropland and grazed pastureland segmented and reduced wetland habitat. Inventorying and characterizing remaining wetland habitat is critical for the management of wetland ecosystem services. Remote sensing technologies are often utilized for mapping and monitoring wetlands. This chapter presents background specific to the PPR and discusses approaches employed in mapping its wetlands before presenting a case study.

  15. Geomorphologic mapping of titan's polar terrains: Constraining surface processes and landscape evolution

    NASA Astrophysics Data System (ADS)

    Birch, S. P. D.; Hayes, A. G.; Dietrich, W. E.; Howard, A. D.; Bristow, C. S.; Malaska, M. J.; Moore, J. M.; Mastrogiuseppe, M.; Hofgartner, J. D.; Williams, D. A.; White, O. L.; Soderblom, J. M.; Barnes, J. W.; Turtle, E. P.; Lunine, J. I.; Wood, C. A.; Neish, C. D.; Kirk, R. L.; Stofan, E. R.; Lorenz, R. D.; Lopes, R. M. C.

    2017-01-01

    We present a geomorphologic map of Titan's polar terrains. The map was generated from a combination of Cassini Synthetic Aperture Radar (SAR) and Imaging Science Subsystem imaging products, as well as altimetry, SARTopo and radargrammetry topographic datasets. In combining imagery with topographic data, our geomorphologic map reveals a stratigraphic sequence from which we infer process interactions between units. In mapping both polar regions with the same geomorphologic units, we conclude that processes that formed the terrains of the north polar region also acted to form the landscape we observe at the south. Uniform, SAR-dark plains are interpreted as sedimentary deposits, and are bounded by moderately dissected uplands. These plains contain the highest density of filled and empty lake depressions, and canyons. These units unconformably overlay a basement rock that outcrops as mountains and SAR-bright dissected terrains at various elevations across both poles. All these units are then superposed by surficial units that slope towards the seas, suggestive of subsequent overland transport of sediment. From estimates of the depths of the embedded empty depressions and canyons that drain into the seas, the SAR-dark plains must be >600 m thick in places, though the thickness may vary across the poles. At the lowest elevations of each polar region, there are large seas, which are currently liquid methane/ethane filled at the north and empty at the south. The large plains deposits and the surrounding hillslopes may represent remnant landforms that are a result of previously vast polar oceans, where larger liquid bodies may have allowed for a sustained accumulation of soluble and insoluble sediments, potentially forming layered sedimentary deposits. Coupled with vertical crustal movements, the resulting layers would be of varying solubilities and erosional resistances, allowing formation of the complex landscape that we observe today.

  16. Simultaneous Mapping of Titan's Atmospheric and Surface Properties Through the Massive Inversion of Cassini/VIMS Data

    NASA Astrophysics Data System (ADS)

    Rodriguez, S.; Maltagliati, L.; Appéré, T.; Vincendon, M.; Douté, S.; Le Mouelic, S.; Rannou, P.; Sotin, C.; Barnes, J. W.; Coustenis, A.; Brown, R. H.

    2014-12-01

    A radiative transfer solver (i.e. SHDOM) is the most powerful tool to extract simultaneous information of the atmosphere and the surface of Titan from the hyperspectral data of the VIMS imaging spectrometer onboard Cassini. However, the sheer amount of data (~40000 VIMS cubes containing several millions of spectra since the beginning of the mission) makes this approach too demanding in computational time. In our analysis we use a radiative transfer model to create look-up tables for different values of the model's parameters (geometry of the observation, surface albedo, aerosols opacity). We employ up-to-date information on gaseous spectral coefficients, aerosols' optical properties and Titan's climatology. These look-up tables, appropriately interpolated, are then used to minimize the observations and create simultaneous maps of surface albedo at the wavelengths of Titan's spectral windows and of aerosols opacity. This approach allows the gain of a factor of several thousands in computational time and thus, for the first time, a truly massive treatment of VIMS data. This capacity of processing full mapping quickly will consent to monitor closely the global and local seasonal evolution of the atmosphere and the surface. We will present the results of our method applied to some cases of interest. We will analyze several hyperspectral images of the Huygens landing site and show the comparison of our results with observations of other Cassini instruments. We will also investigate regions that have been observed multiple times at different Cassini flybys with different observational conditions, as the T13/T17 mosaic of the Atzlan area. The perspectives for atmospheric and surface seasonal monitoring will be highlighted.

  17. AN ACCURACY ASSESSMENT OF MULTIPLE MID-ATLANTIC SUB-PIXEL IMPERVIOUS SURFACE MAPS

    EPA Science Inventory

    Anthropogenic impervious surfaces have an important relationship with non-point source pollution (NPS) in urban watersheds. The amount of impervious surface area in a watershed is a key indicator of landscape change. As a single variable, it serves to integrate a number of conc...

  18. Fluorescent stereo microscopy for 3D surface profilometry and deformation mapping.

    PubMed

    Hu, Zhenxing; Luo, Huiyang; Du, Yingjie; Lu, Hongbing

    2013-05-20

    Recently, mechanobiology has received increased attention. For investigation of biofilm and cellular tissue, measurements of the surface topography and deformation in real-time are a pre-requisite for understanding the growth mechanisms. In this paper, a novel three-dimensional (3D) fluorescent microscopic method for surface profilometry and deformation measurements is developed. In this technique a pair of cameras are connected to a binocular fluorescent microscope to acquire micrographs from two different viewing angles of a sample surface doped or sprayed with fluorescent microparticles. Digital image correlation technique is used to search for matching points in the pairing fluorescence micrographs. After calibration of the system, the 3D surface topography is reconstructed from the pair of planar images. When the deformed surface topography is compared with undeformed topography using fluorescent microparticles for movement tracking of individual material points, the full field deformation of the surface is determined. The technique is demonstrated on topography measurement of a biofilm, and also on surface deformation measurement of the biofilm during growth. The use of 3D imaging of the fluorescent microparticles eliminates the formation of bright parts in an image caused by specular reflections. The technique is appropriate for non-contact, full-field and real-time 3D surface profilometry and deformation measurements of materials and structures at the microscale.

  19. Sensitivity of thermal inertia calculations to variations in environmental factors. [in mapping of Earth's surface by remote sensing

    NASA Technical Reports Server (NTRS)

    Kahle, A. B.; Alley, R. E.; Schieldge, J. P.

    1984-01-01

    The sensitivity of thermal inertia (TI) calculations to errors in the measurement or parameterization of a number of environmental factors is considered here. The factors include effects of radiative transfer in the atmosphere, surface albedo and emissivity, variations in surface turbulent heat flux density, cloud cover, vegetative cover, and topography. The error analysis is based upon data from the Heat Capacity Mapping Mission (HCMM) satellite for July 1978 at three separate test sites in the deserts of the western United States. Results show that typical errors in atmospheric radiative transfer, cloud cover, and vegetative cover can individually cause root-mean-square (RMS) errors of about 10 percent (with atmospheric effects sometimes as large as 30-40 percent) in HCMM-derived thermal inertia images of 20,000-200,000 pixels.

  20. Advances in Shallow-Water, High-Resolution Seafloor Mapping: Integrating an Autonomous Surface Vessel (ASV) Into Nearshore Geophysical Studies

    NASA Astrophysics Data System (ADS)

    Denny, J. F.; O'Brien, T. F.; Bergeron, E.; Twichell, D.; Worley, C. R.; Danforth, W. W.; Andrews, B. A.; Irwin, B.

    2006-12-01

    The U.S. Geological Survey (USGS) has been heavily involved in geological mapping of the seafloor since the 1970s. Early mapping efforts such as GLORIA provided broad-scale imagery of deep waters (depths > 400 meters) within the Exclusive Economic Zone (EEZ). In the early 1990's, the USGS research emphasis shifted from deep- to shallow-water environments (inner continental shelf, nearshore, estuaries) to address pertinent coastal issues such as erosion, sediment availability, sediment transport, vulnerability of coastal areas to natural and anthropogenic hazards, and resource management. Geologic framework mapping in these shallow- water environments has provided valuable data used to 1) define modern sediment distribution and thickness, 2) determine underlying stratigraphic and structural controls on shoreline behavior, and 3) enable onshore-to- offshore geologic mapping within the coastal zone when coupled with subaerial techniques such as GPR and topographic LIDAR. Research in nearshore areas presents technological challenges due to the dynamics of the environment, high volume of data collected, and the geophysical limitations of operating in very shallow water. In 2004, the USGS, in collaboration with NOAA's Coastal Services Center, began a multi-year seafloor mapping effort to better define oyster habitats within Apalachicola Bay, Florida, a shallow water estuary along the northern Gulf of Mexico. The bay poses a technological challenge due to its shallow depths (< 4-m) and high turbidity that prohibits the use of bathymetric LIDAR. To address this extreme shallow water setting, the USGS incorporated an Autonomous Surface Vessel (ASV) into seafloor mapping operations, in June 2006. The ASV is configured with a chirp sub-bottom profiler (4 24 kHz), dual-frequency chirp sidescan-sonar (100/500 kHz), single-beam echosounder (235 kHz), and forward-looking digital camera, and will be used to delineate the distribution and thickness of surficial sediment, presence

  1. The control network of Rhea. [surface feature coordinates for satellite mapping

    NASA Technical Reports Server (NTRS)

    Davies, M. E.; Katayama, F. Y.

    1983-01-01

    A control network of the Saturnian satellite Rhea has been established photogrammetrically from pictures taken by the two Voyager spacecraft. Coordinates of 288 control points on Rhea have been computed and listed; some of these are identified on the preliminary U.S. Geological Survey map of Rhea and many of the control point features have been named. Pixel measurements of these points were made on 81 Voyager 1 and 3 Voyager 2 pictures. The longitude system on Rhea is defined by the crater Tore; the 340 deg meridian passes through the center of this crater. The mean radius of Rhea has been determined at 764 + or - 4 km.

  2. Mapping the Atmospheric and Surface Properties of Titan by the Massive Inversion of Cassini/VIMS Spectra

    NASA Astrophysics Data System (ADS)

    Maltagliati, Luca; Rodriguez, Sébastien; Appéré, Thomas; Vincendon, Mathieu; Douté, Sylvain; LeMouelic, Stéphane; Rannou, Pascal; Sotin, Christophe; Barnes, Jason W.; Coustenis, Athena; Brown, Robert H.

    2014-11-01

    Since the beginning of the Cassini mission, the imaging spectrometer VIMS has acquired ~40000 hyperspectral images of Titan containing several millions of spectra. Such a huge amount of data cannot be analyzed with a radiative transfer solver like SHDOM because of computational limits. Nevertheless, such a solver is the most suited tool to extract simultaneous information of the atmosphere and the surface of Titan from VIMS datacubes. We have developed a method of analyzing VIMS data that consents to use the power of a RT model without the inconvenience of long computational times, by the creation of look-up tables for different values of the RT model's parameters (geometry of the observation, surface albedo, aerosols opacity). We employ up-to-date information on gaseous spectral coefficients, aerosols’ optical properties and Titan’s climatology. These look-up tables, appropriately interpolated, are then used to minimize the observations and create simultaneous maps of aerosols opacity and of surface albedo (at the wavelengths of Titan’s spectral windows). This method lowers the computational time by a factor of several thousands and thus, for the first time, a truly massive treatment of VIMS data. In this paper we present the results of our method applied to the area of the Huygens landing site and their comparison with the results of other Cassini instruments. We also show the retrieved maps of a region observed multiple times at different Cassini flybys with different observational conditions, as the T13/T17 mosaic of the Atzlan area. The perspectives for atmospheric and surface seasonal monitoring are highlighted.

  3. Using Image Pro Plus Software to Develop Particle Mapping on Genesis Solar Wind Collector Surfaces

    NASA Astrophysics Data System (ADS)

    Rodriguez, M. C.; Allton, J. H.; Burkett, P. J.

    2012-03-01

    The Genesis curatorial facility at JSC provides optical analysis of collector array surfaces as cleaning steps progress in an updated master cleaning plan coordinated by the Genesis mission PI Don Burnett.

  4. High-resolution mapping of global surface water and its long-term changes.

    PubMed

    Pekel, Jean-François; Cottam, Andrew; Gorelick, Noel; Belward, Alan S

    2016-12-15

    The location and persistence of surface water (inland and coastal) is both affected by climate and human activity and affects climate, biological diversity and human wellbeing. Global data sets documenting surface water location and seasonality have been produced from inventories and national descriptions, statistical extrapolation of regional data and satellite imagery, but measuring long-term changes at high resolution remains a challenge. Here, using three million Landsat satellite images, we quantify changes in global surface water over the past 32 years at 30-metre resolution. We record the months and years when water was present, where occurrence changed and what form changes took in terms of seasonality and persistence. Between 1984 and 2015 permanent surface water has disappeared from an area of almost 90,000 square kilometres, roughly equivalent to that of Lake Superior, though new permanent bodies of surface water covering 184,000 square kilometres have formed elsewhere. All continental regions show a net increase in permanent water, except Oceania, which has a fractional (one per cent) net loss. Much of the increase is from reservoir filling, although climate change is also implicated. Loss is more geographically concentrated than gain. Over 70 per cent of global net permanent water loss occurred in the Middle East and Central Asia, linked to drought and human actions including river diversion or damming and unregulated withdrawal. Losses in Australia and the USA linked to long-term droughts are also evident. This globally consistent, validated data set shows that impacts of climate change and climate oscillations on surface water occurrence can be measured and that evidence can be gathered to show how surface water is altered by human activities. We anticipate that this freely available data will improve the modelling of surface forcing, provide evidence of state and change in wetland ecotones (the transition areas between biomes), and inform water

  5. High-resolution mapping of global surface water and its long-term changes

    NASA Astrophysics Data System (ADS)

    Pekel, Jean-François; Cottam, Andrew; Gorelick, Noel; Belward, Alan S.

    2016-12-01

    The location and persistence of surface water (inland and coastal) is both affected by climate and human activity and affects climate, biological diversity and human wellbeing. Global data sets documenting surface water location and seasonality have been produced from inventories and national descriptions, statistical extrapolation of regional data and satellite imagery, but measuring long-term changes at high resolution remains a challenge. Here, using three million Landsat satellite images, we quantify changes in global surface water over the past 32 years at 30-metre resolution. We record the months and years when water was present, where occurrence changed and what form changes took in terms of seasonality and persistence. Between 1984 and 2015 permanent surface water has disappeared from an area of almost 90,000 square kilometres, roughly equivalent to that of Lake Superior, though new permanent bodies of surface water covering 184,000 square kilometres have formed elsewhere. All continental regions show a net increase in permanent water, except Oceania, which has a fractional (one per cent) net loss. Much of the increase is from reservoir filling, although climate change is also implicated. Loss is more geographically concentrated than gain. Over 70 per cent of global net permanent water loss occurred in the Middle East and Central Asia, linked to drought and human actions including river diversion or damming and unregulated withdrawal. Losses in Australia and the USA linked to long-term droughts are also evident. This globally consistent, validated data set shows that impacts of climate change and climate oscillations on surface water occurrence can be measured and that evidence can be gathered to show how surface water is altered by human activities. We anticipate that this freely available data will improve the modelling of surface forcing, provide evidence of state and change in wetland ecotones (the transition areas between biomes), and inform water

  6. Adhesion force mapping on wood by atomic force microscopy: influence of surface roughness and tip geometry.

    PubMed

    Jin, X; Kasal, B

    2016-10-01

    This study attempts to address the interpretation of atomic force microscopy (AFM) adhesion force measurements conducted on the heterogeneous rough surface of wood and natural fibre materials. The influences of wood surface roughness, tip geometry and wear on the adhesion force distribution are examined by cyclic measurements conducted on wood surface under dry inert conditions. It was found that both the variation of tip and surface roughness of wood can widen the distribution of adhesion forces, which are essential for data interpretation. When a common Si AFM tip with nanometre size is used, the influence of tip wear can be significant. Therefore, control experiments should take the sequence of measurements into consideration, e.g. repeated experiments with used tip. In comparison, colloidal tips provide highly reproducible results. Similar average values but different distributions are shown for the adhesion measured on two major components of wood surface (cell wall and lumen). Evidence supports the hypothesis that the difference of the adhesion force distribution on these two locations was mainly induced by their surface roughness.

  7. Adhesion force mapping on wood by atomic force microscopy: influence of surface roughness and tip geometry

    NASA Astrophysics Data System (ADS)

    Jin, X.; Kasal, B.

    2016-10-01

    This study attempts to address the interpretation of atomic force microscopy (AFM) adhesion force measurements conducted on the heterogeneous rough surface of wood and natural fibre materials. The influences of wood surface roughness, tip geometry and wear on the adhesion force distribution are examined by cyclic measurements conducted on wood surface under dry inert conditions. It was found that both the variation of tip and surface roughness of wood can widen the distribution of adhesion forces, which are essential for data interpretation. When a common Si AFM tip with nanometre size is used, the influence of tip wear can be significant. Therefore, control experiments should take the sequence of measurements into consideration, e.g. repeated experiments with used tip. In comparison, colloidal tips provide highly reproducible results. Similar average values but different distributions are shown for the adhesion measured on two major components of wood surface (cell wall and lumen). Evidence supports the hypothesis that the difference of the adhesion force distribution on these two locations was mainly induced by their surface roughness.

  8. Adhesion force mapping on wood by atomic force microscopy: influence of surface roughness and tip geometry

    PubMed Central

    Kasal, B.

    2016-01-01

    This study attempts to address the interpretation of atomic force microscopy (AFM) adhesion force measurements conducted on the heterogeneous rough surface of wood and natural fibre materials. The influences of wood surface roughness, tip geometry and wear on the adhesion force distribution are examined by cyclic measurements conducted on wood surface under dry inert conditions. It was found that both the variation of tip and surface roughness of wood can widen the distribution of adhesion forces, which are essential for data interpretation. When a common Si AFM tip with nanometre size is used, the influence of tip wear can be significant. Therefore, control experiments should take the sequence of measurements into consideration, e.g. repeated experiments with used tip. In comparison, colloidal tips provide highly reproducible results. Similar average values but different distributions are shown for the adhesion measured on two major components of wood surface (cell wall and lumen). Evidence supports the hypothesis that the difference of the adhesion force distribution on these two locations was mainly induced by their surface roughness. PMID:27853541

  9. Temporal and spatial mapping of surface albedo and atmospheric dust opacity on Mars

    NASA Technical Reports Server (NTRS)

    Lee, S. W.; Clancy, R. T.; Gladstone, G. R.

    1993-01-01

    The Mariner 9 and Viking provided abundant evidence that eolian processes are active over much of the surface of Mars. Past studies have demonstrated that variations in regional albedo and wind-streak patterns are indicative of sediment transport through a region, while thermal inertia data (derived from the Viking Infrared Thermal Mapper (IRTM) dataset) are indicative of the degree of surface mantling by dust deposits. The visual and thermal data are therefore diagnostic of whether net erosion or deposition of dust-storm fallout is taking place currently and whether such processes have been active in a region over the long term. These previous investigations, however, have not attempted to correct for the effects of atmospheric dust loading on observations of the martian surface, so quantitative studies of current sediment transport rates have included large errors due to uncertainty in the magnitude of this 'atmospheric component' of the observations. We have developed a radiative transfer model that allows the atmospheric dust opacity to be determined from IRTM thermal observations. Corrections for the effects of atmospheric dust loading on observations of surface albedo can also be modeled. This approach to determining 'dust-corrected surface albedo' incorporates the atmospheric dust opacity, the single-scattering albedo and particle phase function of atmospheric dust, and the bidirectional reflectance of the surface, and it accounts for variable lighting and viewing geometry.

  10. Surface invasive cleavage assay on a maskless light-directed diamond DNA microarray for genome-wide human SNP mapping.

    PubMed

    Nie, Bei; Yang, Min; Fu, Weiling; Liang, Zhiqing

    2015-07-07

    The surface invasive cleavage assay, because of its innate accuracy and ability for self-signal amplification, provides a potential route for the mapping of hundreds of thousands of human SNP sites. However, its performance on a high density DNA array has not yet been established, due to the unusual "hairpin" probe design on the microarray and the lack of chemical stability of commercially available substrates. Here we present an applicable method to implement a nanocrystalline diamond thin film as an alternative substrate for fabricating an addressable DNA array using maskless light-directed photochemistry, producing the most chemically stable and biocompatible system for genetic analysis and enzymatic reactions. The surface invasive cleavage reaction, followed by degenerated primer ligation and post-rolling circle amplification is consecutively performed on the addressable diamond DNA array, accurately mapping SNP sites from PCR-amplified human genomic target DNA. Furthermore, a specially-designed DNA array containing dual probes in the same pixel is fabricated by following a reverse light-directed DNA synthesis protocol. This essentially enables us to decipher thousands of SNP alleles in a single-pot reaction by the simple addition of enzyme, target and reaction buffers.

  11. Calculating High Resolution CWSI Maps for Entire Growing Season of a Cultivated Barley Field with UAV-Collected Surface Temperatures.

    NASA Astrophysics Data System (ADS)

    Hoffmann, H.; Jensen, R.; Nieto Solana, H.; Friborg, T.; Thomsen, A.

    2015-12-01

    With agriculture as the largest consumer of freshwater and an overall increasing pressure on water resources, developing more efficient irrigation systems is important. Combining the crop water stress index (CWSI) with unmanned aerial vehicles (UAVs) enables detection of which specific areas within a cultivated field that requires irrigation to ensure healthy growing plants. In this study remotely sensed, high resolution surface temperatures are collected with a thermal camera onboard an UAV. Temperatures are used to calculate spatially distributed, high resolution CWSI maps over a barley field during growing seasons 2014 and 2015. In early stages of the barley growing season, surface temperatures are an ensemble of both soil and canopy temperatures. Canopy temperatures are extracted using leaf area index and the two source energy balance modelling scheme. This approach enables CWSI calculations for homogeneous and evenly distributed crops (such as barley) during early as well as late stages of a growing season. CWSI maps are calculated using both an empirical and an analytical approach and are compared and validated against modelled canopy conductance and transpiration rates.

  12. Mapping of Synaptic-Neuronal Impairment on the Brain Surface through Fluctuation Analysis

    SciTech Connect

    Musha, Toshimitsu; Kurachi, Takayoshi; Suzuki, Naohoro; Kosugi, Yukio

    2005-08-25

    Increase of demented population year by year is becoming a serious social problem to be solved urgently. The most effective way to block this increase is in its early detection by means of an inexpensive, non-invasive, sensitive, reliable and easy-to-operate diagnosis method. We have developed a method satisfying these requirements by using scalp potential fluctuations. We have collected 21ch EEG and SPECT data of 25 very mild Alzheimer's disease (AD) (MMSE=26{+-}1.8), moderately severe AD (MMSE=15.3{+-}6.4) and age-matched normal controls. As AD progresses, local synaptic-neuronal activity becomes abnormal, either more unstable or more inactive than in normal state. Such abnormality is detected in terms of normalized power variance (NPV) of a scalp potential recorded with a scalp electrode. The z-score is defined by z = ((NPV of a subject) - (mean NPV of normal subjects))/(standard deviation of NPV of normal subjects). Correlation of a measured z-score map with the mean z-score map for AD patients characterizes likelihood to AD, in terms of which AD is discriminated from normal with 75% of true positive and 25% false negative probability. By introducing two thresholds, we have 90% of true positive and 10% of false negative discrimination.

  13. Mapping of Synaptic-Neuronal Impairment on the Brain Surface through Fluctuation Analysis

    NASA Astrophysics Data System (ADS)

    Musha, Toshimitsu; Kurachi, Takayoshi; Suzuki, Naohoro; Kosugi, Yukio

    2005-08-01

    Increase of demented population year by year is becoming a serious social problem to be solved urgently. The most effective way to block this increase is in its early detection by means of an inexpensive, non-invasive, sensitive, reliable and easy-to-operate diagnosis method. We have developed a method satisfying these requirements by using scalp potential fluctuations. We have collected 21ch EEG and SPECT data of 25 very mild Alzheimer's disease (AD) (MMSE=26±1.8), moderately severe AD (MMSE=15.3±6.4) and age-matched normal controls. As AD progresses, local synaptic-neuronal activity becomes abnormal, either more unstable or more inactive than in normal state. Such abnormality is detected in terms of normalized power variance (NPV) of a scalp potential recorded with a scalp electrode. The z-score is defined by z = ((NPV of a subject) — (mean NPV of normal subjects))/(standard deviation of NPV of normal subjects). Correlation of a measured z-score map with the mean z-score map for AD patients characterizes likelihood to AD, in terms of which AD is discriminated from normal with 75% of true positive and 25% false negative probability. By introducing two thresholds, we have 90% of true positive and 10% of false negative discrimination.

  14. An unusual MAP kinase is required for efficient penetration of the plant surface by Ustilago maydis

    PubMed Central

    Brachmann, Andreas; Schirawski, Jan; Müller, Philip; Kahmann, Regine

    2003-01-01

    In Ustilago maydis, pathogenic development is controlled by a heterodimer of the two homeodomain proteins bW and bE. We have identified by RNA fingerprinting a b-regulated gene, kpp6, which encodes an unusual MAP kinase. Kpp6 is similar to a number of other fungal MAP kinases involved in mating and pathogenicity, but contains an additional N-terminal domain unrelated to other proteins. Transcription of the kpp6 gene yields two transcripts differing in length, but encoding proteins of identical mass. One transcript is upregulated by the bW/bE heterodimer, while the other is induced after pheromone stimulation. kpp6 deletion mutants are attenuated in pathogenicity. kpp6T355A,Y357F mutants carrying a non-activatable allele of kpp6 are more severely compromised in pathogenesis. These strains can still form appressoria, but are defective in the subsequent penetration of the plant cuticle. Kpp6 is expressed during all stages of the sexual life cycle except mature spores. We speculate that Kpp6 may respond to a plant signal and regulate the genes necessary for efficient penetration of plant tissue. PMID:12727886

  15. An unusual MAP kinase is required for efficient penetration of the plant surface by Ustilago maydis.

    PubMed

    Brachmann, Andreas; Schirawski, Jan; Müller, Philip; Kahmann, Regine

    2003-05-01

    In Ustilago maydis, pathogenic development is controlled by a heterodimer of the two homeodomain proteins bW and bE. We have identified by RNA fingerprinting a b-regulated gene, kpp6, which encodes an unusual MAP kinase. Kpp6 is similar to a number of other fungal MAP kinases involved in mating and pathogenicity, but contains an additional N-terminal domain unrelated to other proteins. Transcription of the kpp6 gene yields two transcripts differing in length, but encoding proteins of identical mass. One transcript is upregulated by the bW/bE heterodimer, while the other is induced after pheromone stimulation. kpp6 deletion mutants are attenuated in pathogenicity. kpp6(T355A,Y357F) mutants carrying a non-activatable allele of kpp6 are more severely compromised in pathogenesis. These strains can still form appressoria, but are defective in the subsequent penetration of the plant cuticle. Kpp6 is expressed during all stages of the sexual life cycle except mature spores. We speculate that Kpp6 may respond to a plant signal and regulate the genes necessary for efficient penetration of plant tissue.

  16. Dust transport over the eastern Mediterranean derived from Total Ozone Mapping Spectrometer, Aerosol Robotic Network, and surface measurements

    NASA Astrophysics Data System (ADS)

    Kalivitis, N.; Gerasopoulos, E.; Vrekoussis, M.; Kouvarakis, G.; Kubilay, N.; Hatzianastassiou, N.; Vardavas, I.; Mihalopoulos, N.

    2007-02-01

    Multiyear surface PM10 measurements performed on Crete Island, Greece, have been used in conjunction with satellite (Total Ozone Mapping Spectrometer (TOMS)) and ground-based remote sensing measurements (Aerosol Robotic Network (AERONET)) to enhance our understanding of the evolution of mineral dust events over the eastern Mediterranean. An analysis of southerly air masses at altitudes of 1000 and 3000 m over a 5 year period (2000-2005), showed that dust can potentially arrive over Crete, either simultaneously in the lower free troposphere and inside the boundary layer (vertical extended transport (VET)) or initially into the free troposphere with the heavier particles gradually being scavenged inside the boundary layer (free troposphere transport (FTT)). Both pathways present significant seasonal variations but on an annual basis contribute almost equally to the dust transport in the area. During VET the aerosol index (AI) derived from TOMS was significantly correlated with surface PM10, and in general AI was found to be adequate for the characterization of dust loadings over the eastern Mediterranean on a climatological basis. A significant covariance between PM10 and AOT was observed during VET as well, indicating that AOT levels from AERONET may be estimated by PM10 levels at the surface. Surface measurements are thus crucial for the validation of remote sensing measurements and hence are a powerful tool for the investigation of the impact of aerosols on climate.

  17. Effects of Surface Albedo on Smoke Detection Through Geostationary Satellite Imagery in the Hazard Mapping System (HMS)

    NASA Astrophysics Data System (ADS)

    Salemi, A.; Ruminski, M. G.

    2012-12-01

    The Satellite Analysis Branch (SAB) of NOAA/NESDIS uses geostationary and polar orbiting satellite imagery to identify fires and smoke throughout the continental United States. The fires and smoke are analyzed daily on the Hazard Mapping System (HMS) and made available via the internet in various formats. Analysis of smoke plumes generated from wildfires, agricultural and prescribe burns is performed with single channel visible imagery primarily from NOAA's Geostationary Operational Environmental Satellite (GOES) animations. Identification of smoke in visible imagery is complicated by the presence of clouds, the viewing angle produced by the sun, smoke, satellite geometry, and the surface albedo of the ground below the smoke among other factors. This study investigates the role of surface albedo in smoke detection. LIght Detection And Ranging (LIDAR) instruments are capable of detecting smoke and other aerosols. Through the use of ground and space based LIDAR systems in areas of varying albedo a relationship between the subjective analyst drawn smoke plumes versus those detected by LIDAR is established. The ability to detect smoke over regions of higher albedo (brighter surface, such as grassland, scrub and desert) is diminished compared to regions of lower albedo (darker surface, such as forest and water). Users of the HMS smoke product need to be aware of this limitation in smoke detection in areas of higher albedo.

  18. Real-Time and in Situ Monitoring of Pesticide Penetration in Edible Leaves by Surface-Enhanced Raman Scattering Mapping.

    PubMed

    Yang, Tianxi; Zhang, Zhiyun; Zhao, Bin; Hou, Ruyan; Kinchla, Amanda; Clark, John M; He, Lili

    2016-05-17

    Understanding of the penetration behaviors of pesticides in fresh produce is of great significance for effectively applying pesticides and minimizing pesticide residues in food. There is lack, however, of an effective method that can measure pesticide penetration. Herein, we developed a novel method for real-time and in situ monitoring of pesticide penetration behaviors in spinach leaves based on surface-enhanced Raman scattering (SERS) mapping. Taking advantage of penetrative gold nanoparticles (AuNPs) as probes to enhance the internalized pesticide signals in situ, we have successfully obtained the internal signals from thiabendazole, a systemic pesticide, following its penetration into spinach leaves after removing surface pesticide residues. Comparatively, ferbam, a nonsystemic pesticide, did not show internal signals after removing surface pesticide residues, demonstrating its nonsystemic behavior. In both cases, if the surface pesticides were not removed, copenetration of both AuNPs and pesticides was observed. These results demonstrate a successful application of SERS as an effective method for measuring pesticides penetration in fresh produce in situ. The information obtained could provide useful guidance for effective and safe applications of pesticides on plants.

  19. Images as embedding maps and minimal surfaces: Movies, color, and volumetric medical images

    SciTech Connect

    Kimmel, R.; Malladi, R.; Sochen, N.

    1997-02-01

    A general geometrical framework for image processing is presented. The authors consider intensity images as surfaces in the (x,I) space. The image is thereby a two dimensional surface in three dimensional space for gray level images. The new formulation unifies many classical schemes, algorithms, and measures via choices of parameters in a {open_quote}master{close_quotes} geometrical measure. More important, it is a simple and efficient tool for the design of natural schemes for image enhancement, segmentation, and scale space. Here the authors give the basic motivation and apply the scheme to enhance images. They present the concept of an image as a surface in dimensions higher than the three dimensional intuitive space. This will help them handle movies, color, and volumetric medical images.

  20. Chemical force mapping of phosphate and carbon on acid-modified tapioca starch surface.

    PubMed

    Wuttisela, Karntarat; Triampo, Wannapong; Triampo, Darapond

    2009-01-01

    Surface chemical microstructure of hydrochloric acid hydrolyzed tapioca starch producing different amylose:amylopectin (Am:Ap) ratios were studied with scanning chemical force microscopy (CFM). The chemical force probes were functionalized of two types with -OH (phosphate specific) and -CH3 (carbon specific). Lateral force trace-minus-retrace (TMR) images from -OH and -CH3 probes revealed changes in the phosphate domains and the carbon backbone for the varying acid hydrolyzed tapioca starch compared to that of the native tapioca starch. Scanning electron micrographs (SEM) showed different degree of the granule surface disruption before and after hydrolysis. The exterior structures of the acid hydrolyzed starch granules were chemically investigated with CFM to study the relationships of the surface molecular structures and the Am:Ap ratios.

  1. Martian Surface NIR Spectral Modeling for Ice Cloud Optical Depth Retrievals using CRISM Mapping Data

    NASA Astrophysics Data System (ADS)

    Klassen, D. R.

    2011-10-01

    One goal in the study of Mars is to understand its water cycle and the total water budget. As part of this, I am working on trying to measure water ice content in Martian clouds. The catch is that in order to measure the water abundance in clouds using near-infrared (NIR) spectra, one must know the surface spectrum, since it is an input for radiative transfer modeling—but to get the surface spectrum, one must be able to remove the effects of the atmosphere and aerosols. I will present four primary methods of modeling away the surface in order to retrieve the ice cloud (and dust) optical depth and compare and contrast them for both ease-of-use and apparent accuracy.

  2. A Digital Map From External Forcing to the Final Surface Warming Pattern and its Seasonal Cycle

    NASA Astrophysics Data System (ADS)

    Cai, M.

    2015-12-01

    Historically, only the thermodynamic processes (e.g., water vapor, cloud, surface albedo, and atmospheric lapse rate) that directly influence the top of the atmosphere (TOA) radiative energy flux balance are considered in climate feedback analysis. One of my recent research areas is to develop a new framework for climate feedback analysis that explicitly takes into consideration not only the thermodynamic processes that the directly influence the TOA radiative energy flux balance but also the local dynamical (e.g., evaporation, surface sensible heat flux, vertical convections etc) and non-local dynamical (large-scale horizontal energy transport) processes in aiming to explain the warming asymmetry between high and low latitudes, between ocean and land, and between the surface and atmosphere. In the last 5-6 years, we have developed a coupled atmosphere-surface climate feedback-response analysis method (CFRAM) as a new framework for estimating climate feedback and sensitivity in coupled general circulation models with a full physical parameterization package. In the CFRAM, the isolation of partial temperature changes due to an external forcing alone or an individual feedback is achieved by solving the linearized infrared radiation transfer model subject to individual energy flux perturbations (external or due to feedbacks). The partial temperature changes are addable and their sum is equal to the (total) temperature change (in the linear sense). The CFRAM is used to isolate the partial temperature changes due to the external forcing, due to water vapor feedback, clouds, surface albedo, local vertical convection, and non-local atmospheric dynamical feedbacks, as well as oceanic heat storage. It has been shown that seasonal variations in the cloud feedback, surface albedo feedback, and ocean heat storage/dynamics feedback, directly caused by the strong annual cycle of insolation, contribute primarily to the large seasonal variation of polar warming. Furthermore, the

  3. Mapping Surface Cover Parameters Using Aggregation Rules and Remotely Sensed Cover Classes. Version 1.9

    NASA Technical Reports Server (NTRS)

    Arain, Altaf M.; Shuttleworth, W. James; Yang, Z-Liang; Michaud, Jene; Dolman, Johannes

    1997-01-01

    A coupled model, which combines the Biosphere-Atmosphere Transfer Scheme (BATS) with an advanced atmospheric boundary-layer model, was used to validate hypothetical aggregation rules for BATS-specific surface cover parameters. The model was initialized and tested with observations from the Anglo-Brazilian Amazonian Climate Observational Study and used to simulate surface fluxes for rain forest and pasture mixes at a site near Manaus in Brazil. The aggregation rules are shown to estimate parameters which give area-average surface fluxes similar to those calculated with explicit representation of forest and pasture patches for a range of meteorological and surface conditions relevant to this site, but the agreement deteriorates somewhat when there are large patch-to-patch differences in soil moisture. The aggregation rules, validated as above, were then applied to remotely sensed 1 km land cover data set to obtain grid-average values of BATS vegetation parameters for 2.8 deg x 2.8 deg and 1 deg x 1 deg grids within the conterminous United States. There are significant differences in key vegetation parameters (aerodynamic roughness length, albedo, leaf area index, and stomatal resistance) when aggregate parameters are compared to parameters for the single, dominant cover within the grid. However, the surface energy fluxes calculated by stand-alone BATS with the 2-year forcing, data from the International Satellite Land Surface Climatology Project (ISLSCP) CDROM were reasonably similar using aggregate-vegetation parameters and dominant-cover parameters, but there were some significant differences, particularly in the western USA.

  4. Microscopic calculation of interacting boson model parameters by potential-energy surface mapping

    SciTech Connect

    Bentley, I.; Frauendorf, S.

    2011-06-15

    A coherent state technique is used to generate an interacting boson model (IBM) Hamiltonian energy surface which is adjusted to match a mean-field energy surface. This technique allows the calculation of IBM Hamiltonian parameters, prediction of properties of low-lying collective states, as well as the generation of probability distributions of various shapes in the ground state of transitional nuclei, the last two of which are of astrophysical interest. The results for krypton, molybdenum, palladium, cadmium, gadolinium, dysprosium, and erbium nuclei are compared with experiment.

  5. Surface Circulation in the Iroise Sea (W. Brittany) from High Resolution HF Radar Mapping

    DTIC Science & Technology

    2013-01-01

    surface, Weber and Barrick (1977) slightly modified this relationship accounting for all types of the surface gravity waves. Broche et al. (1983) provided...f0∫2π0 f kE f ; θð Þdf dθ; ðA2Þ with f the wave frequency, k the wavenumber and E(f,θ) the sea sur- face elevation spectrum. Uss writes as ( Broche et...161–182. Broche , P., De Maistre, J.C., Forget, P., 1983. Mesure par radar décamétrique cohérent des courants superficiels engendrés par le vent

  6. "True" color surface anatomy: mapping the Visible Human to patient-specific CT data.

    PubMed

    Kerr, J P; Knapp, D; Frake, B; Sellberg, M

    2000-01-01

    The mapping of "true" color and texture information into traditional medical imaging modality data can add considerable information and aid in diagnostics. One of the goals of this work has been to create CT color lookup tables for all visually well-defined structures in the Visible Human male cryosection data set which then can be used to color patient-specific CT data. The primary goal has been to develop a method for stripping textures from a volumetric data set for polygonal models and non-uniform rational B-spline (NURBS) models generated from a volumetric data set. It is believed that these methods can eventually be used to provide clinicians with 3D models with physiologically accurate color textures.

  7. Multi-dimensional super-resolution imaging enables surface hydrophobicity mapping

    PubMed Central

    Bongiovanni, Marie N.; Godet, Julien; Horrocks, Mathew H.; Tosatto, Laura; Carr, Alexander R.; Wirthensohn, David C.; Ranasinghe, Rohan T.; Lee, Ji-Eun; Ponjavic, Aleks; Fritz, Joelle V.; Dobson, Christopher M.; Klenerman, David; Lee, Steven F.

    2016-01-01

    Super-resolution microscopy allows biological systems to be studied at the nanoscale, but has been restricted to providing only positional information. Here, we show that it is possible to perform multi-dimensional super-resolution imaging to determine both the position and the environmental properties of single-molecule fluorescent emitters. The method presented here exploits the solvatochromic and fluorogenic properties of nile red to extract both the emission spectrum and the position of each dye molecule simultaneously enabling mapping of the hydrophobicity of biological structures. We validated this by studying synthetic lipid vesicles of known composition. We then applied both to super-resolve the hydrophobicity of amyloid aggregates implicated in neurodegenerative diseases, and the hydrophobic changes in mammalian cell membranes. Our technique is easily implemented by inserting a transmission diffraction grating into the optical path of a localization-based super-resolution microscope, enabling all the information to be extracted simultaneously from a single image plane. PMID:27929085

  8. Multi-dimensional super-resolution imaging enables surface hydrophobicity mapping

    NASA Astrophysics Data System (ADS)

    Bongiovanni, Marie N.; Godet, Julien; Horrocks, Mathew H.; Tosatto, Laura; Carr, Alexander R.; Wirthensohn, David C.; Ranasinghe, Rohan T.; Lee, Ji-Eun; Ponjavic, Aleks; Fritz, Joelle V.; Dobson, Christopher M.; Klenerman, David; Lee, Steven F.

    2016-12-01

    Super-resolution microscopy allows biological systems to be studied at the nanoscale, but has been restricted to providing only positional information. Here, we show that it is possible to perform multi-dimensional super-resolution imaging to determine both the position and the environmental properties of single-molecule fluorescent emitters. The method presented here exploits the solvatochromic and fluorogenic properties of nile red to extract both the emission spectrum and the position of each dye molecule simultaneously enabling mapping of the hydrophobicity of biological structures. We validated this by studying synthetic lipid vesicles of known composition. We then applied both to super-resolve the hydrophobicity of amyloid aggregates implicated in neurodegenerative diseases, and the hydrophobic changes in mammalian cell membranes. Our technique is easily implemented by inserting a transmission diffraction grating into the optical path of a localization-based super-resolution microscope, enabling all the information to be extracted simultaneously from a single image plane.

  9. Determining mean thickness of the oxide layer by mapping the surface of a silicon sphere.

    PubMed

    Zhang, Jitao; Li, Yan; Wu, Xuejian; Luo, Zhiyong; Wei, Haoyun

    2010-03-29

    To determine Avogadro constant with a relative uncertainty of better than 2 x 10(-8), the mean thickness of the oxide layer grown non-uniformly on the silicon sphere should be determined with about 0.1 nm uncertainty. An effective and flexible mapping strategy is proposed, which is insensitive to the angle resolution of the sphere-rotating mechanism. In this method, a sphere-rotating mechanism is associated with spectroscopic ellipsometer to determine the distribution of the layer, and a weighted mean method based on equal-area projection theory is applied to estimate the mean thickness. The spectroscopic ellipsometer is calibrated by X-ray reflectivity method. Within 12 hours, eight hundred positions on the silicon sphere are measured twice. The mean thickness is determined to be 4.23 nm with an uncertainty of 0.13 nm, which is in the acceptable level for the Avogadro project.

  10. Youngstown MAP, Ohio. Revised Uniform Summary of Surface Weather Observations (RUSSWO). Parts A-F.

    DTIC Science & Technology

    1982-05-10

    9497 95.6 95.6 96.1 96.1 96.6 96.6 - 3 E2.4 70.8 74.8 A07 83.6 88.2 9103 93.7 93.7 96.03 97ol 97.1 97.6 97.6 98.1 98.1 a 200 52.4 70.8 74.8 807 83.6...n MAP nb - 7 A __; I S ’ATIOS STATION NAME - -/t. PAGE 2 T..p. WET BULB TEMPERATURE DEPRESSION (F) TOTAL TOTAL (F) 0 I .2 3-4 S- 6 7-. 9.10 111𔃽.1

  11. Monthly Maps of Sea Surface Height in the North Atlantic and Zonal Indices for the Gulf Stream Using TOPEX/Poseidon Altimeter Data

    NASA Technical Reports Server (NTRS)

    Singh, Sandipa; Kelly, Kathryn A.

    1997-01-01

    Monthly Maps of sea surface height are constructed for the North Atlantic Ocean using TOPEX/Poseidon altimeter data. Mean sea surface height is reconstructed using a weighted combination of historical, hydrographic data and a synthetic mean obtained by fitting a Gaussian model of the Gulf Stream jet to altimeter data. The resultant mean shows increased resolution over the hydrographic mean, and incorporates recirculation information that is absent in the synthetic mean. Monthly maps, obtained by adding the mean field to altimeter sea surface height residuals, are used to derive a set of zonal indices that describe the annual cycle of meandering as well as position and strength of the Gulf Stream.

  12. RAPID SPATIAL MAPPING OF CHEMICALS DISPERSED ACROSS SURFACES USING AN AUTOSAMPLER/DART/TOFMS

    EPA Science Inventory

    Rapid identification and semi-quantitation of chemicals spatially dispersed and

    deposited on surfaces by accidental, deliberate, or weather-related events requires analysis of

    hundreds of samples, usually obtained by sampling with wipes. Hand-held devices used on-si...

  13. Mapping the surface-exposed regions of papaya mosaic virus nanoparticles.

    PubMed

    Rioux, Gervais; Majeau, Nathalie; Leclerc, Denis

    2012-06-01

    In general, the structure of the papaya mosaic virus (PapMV) and other members of the potexviruses is poorly understood. Production of PapMV coat proteins in a bacterial expression system and their self-assembly in vitro into nanoparticles is a very useful tool to study the structure of this virus. Using recombinant PapMV nanoparticles that are similar in shape and appearance to the plant virus, we evaluated surface-exposed regions by two different methods, immunoblot assay and chemical modification with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide or diethyl-pyrocarbonate followed by mass spectrometry. Three regions were targeted by the two techniques. The N- and C-termini were shown to be surfaced exposed as expected. However, the region 125-136 was revealed for the first time as the major surface-exposed region of the nanoparticles. The presence of linear peptides at the surface was finally confirmed using antibodies directed to those peptides. It is likely that region 125-136 plays a key role in the lifecycle of PapMV and other members of the potexvirus group.

  14. A novel method for more accurately mapping the surface temperature of ultrasonic transducers.

    PubMed

    Axell, Richard G; Hopper, Richard H; Jarritt, Peter H; Oxley, Chris H

    2011-10-01

    This paper introduces a novel method for measuring the surface temperature of ultrasound transducer membranes and compares it with two standard measurement techniques. The surface temperature rise was measured as defined in the IEC Standard 60601-2-37. The measurement techniques were (i) thermocouple, (ii) thermal camera and (iii) novel infra-red (IR) "micro-sensor." Peak transducer surface measurements taken with the thermocouple and thermal camera were -3.7 ± 0.7 (95% CI)°C and -4.3 ± 1.8 (95% CI)°C, respectively, within the limits of the IEC Standard. Measurements taken with the novel IR micro-sensor exceeded these limits by 3.3 ± 0.9 (95% CI)°C. The ambiguity between our novel method and the standard techniques could have direct patient safety implications because the IR micro-sensor measurements were beyond set limits. The spatial resolution of the measurement technique is not well defined in the IEC Standard and this has to be taken into consideration when selecting which measurement technique is used to determine the maximum surface temperature.

  15. Evaluation of Surface Energy Balance models for mapping evapotranspiration using very high resolution airborne remote sensing data

    NASA Astrophysics Data System (ADS)

    Paul, George

    Agriculture is the largest (90%) consumer of all fresh water in the world. The consumptive use of water by vegetation represented by the process evapotranspiration (ET) has a vital role in the dynamics of water, carbon and energy fluxes of the biosphere. Consequently, mapping ET is essential for making water a sustainable resource and also for monitoring ecosystem response to water stress and changing climate. Over the past three decades, numerous thermal remote sensing based ET mapping algorithms were developed and these have brought a significant theoretical and technical advancement in the spatial modeling of ET. Though these algorithms provided a robust, economical, and efficient tool for ET estimations at field and regional scales, yet the uncertainties in flux estimations were large, making evaluation a difficult task. The main objective of this study was to evaluate and improve the performance of widely used remote sensing based energy balance models, namely: the Surface Energy Balance Algorithm for Land (SEBAL), Mapping Evapotranspiration at high Resolution and with Internalized Calibration (METRIC), and Surface Energy Balance System (SEBS). Data used in this study was collected as part of a multi-disciplinary and multi-institutional field campaign BEAREX (Bushland Evapotranspiration and Agricultural Remote Sensing Experiment) that was conducted during 2007 and 2008 summer cropping seasons at the USDA-ARS Conservation and Production Research Laboratory (CPRL) in Bushland, Texas. Seventeen high resolution remote sensing images taken from multispectral sensors onboard aircraft and field measurements of the agro-meteorological variables from the campaign were used for model evaluation and improvement. Overall relative error measured in terms of mean absolute percent difference (MAPD) for instantaneous ET (mm h -1) were 22.7%, 23.2%, and 12.6% for SEBAL, METRIC, and SEBS, respectively. SEBAL and METRIC performances for irrigated fields representing higher ET

  16. Sea surface temperature of the coastal zones of France. Heat Capacity Mapping Mission (HCMM)

    NASA Technical Reports Server (NTRS)

    Deschamps, P. Y.; Frouin, R.; Cassanet, G.; Verger, F. (Principal Investigator)

    1979-01-01

    The author has identified the following significant results. HCMM data analysis shows some mesoscale features which were previously expected to occur: summer coastal upwellings in the Gulf of Lions, tidal fronts bordering the English Channel, and cooler surface waters at the continental shelf break. The analysis of the spectral variance density spectra show that the interpretation of the data usually is limited by the HCMM radiometric performance (noise levels) at wavenumbers below 5 km in the oceanic areas; from this analysis it may also be concluded that a decrease of the radiometric noise level down to 0.1 k against an increase of the ground resolution up to 2 km would give a better optimum of the radiometric performances in the oceanic areas. HCMM data appear to be useful for analysis of the sea surface temperature field, particularly in the very coastal area by profiting from the ground resolution of 500 m.

  17. Mesoscale Near-Surface Wind Speed Variability Mapping with Synthetic Aperture Radar.

    PubMed

    Young, George; Sikora, Todd; Winstead, Nathaniel

    2008-11-05

    Operationally-significant wind speed variability is often observed within synthetic aperture radar-derived wind speed (SDWS) images of the sea surface. This paper is meant as a first step towards automated distinguishing of meteorological phenomena responsible for such variability. In doing so, the research presented in this paper tests feature extraction and pixel aggregation techniques focused on mesoscale variability of SDWS. A sample of twenty eight SDWS images possessing varying degrees of near-surface wind speed variability were selected to serve as case studies. Gaussian high- and low-pass, local entropy, and local standard deviation filters performed well for the feature extraction portion of the research while principle component analysis of the filtered data performed well for the pixel aggregation. The findings suggest recommendations for future research.

  18. Mapping polarization induced surface band bending on the Rashba semiconductor BiTeI

    NASA Astrophysics Data System (ADS)

    Butler, Christopher John; Yang, Hung-Hsiang; Hong, Jhen-Yong; Hsu, Shih-Hao; Sankar, Raman; Lu, Chun-I.; Lu, Hsin-Yu; Yang, Kui-Hon Ou; Shiu, Hung-Wei; Chen, Chia-Hao; Kaun, Chao-Cheng; Shu, Guo-Jiun; Chou, Fang-Cheng; Lin, Minn-Tsong

    2014-06-01

    Surfaces of semiconductors with strong spin-orbit coupling are of great interest for use in spintronic devices exploiting the Rashba effect. BiTeI features large Rashba-type spin splitting in both valence and conduction bands. Either can be shifted towards the Fermi level by surface band bending induced by the two possible polar terminations, making Rashba spin-split electron or hole bands electronically accessible. Here we demonstrate the first real-space microscopic identification of each termination with a multi-technique experimental approach. Using spatially resolved tunnelling spectroscopy across the lateral boundary between the two terminations, a previously speculated on p-n junction-like discontinuity in electronic structure at the lateral boundary is confirmed experimentally. These findings realize an important step towards the exploitation of the unique behaviour of the Rashba semiconductor BiTeI for new device concepts in spintronics.

  19. Eddy covariance mapping and quantification of surface CO2 leakage fluxes

    SciTech Connect

    Lewicki, J.L.; Hilley, G.E.

    2009-08-01

    We present eddy covariance measurements of net CO{sub 2} flux (F{sub c}) made during a controlled release of CO{sub 2} (0.3 t d{sup -1} from 9 July to 7 August 2008) from a horizontal well {approx}100 m in length and {approx}2.5 m in depth located in an agricultural field in Bozeman, MT. We isolated fluxes arising from the release (F{sub cr}) by subtracting fluxes corresponding to a model for net ecosystem exchange from F{sub c}. A least-squares inversion of 611 F{sub cr} and corresponding modeled footprint functions recovered the location, length, and magnitude of the surface CO{sub 2} flux leakage signal, although high wavenumber details of the signal were poorly resolved. The estimated total surface CO{sub 2} leakage rate (0.32 t d{sup ?1}) was within 7% of the release rate.

  20. Mapping polarization induced surface band bending on the Rashba semiconductor BiTeI

    PubMed Central

    Butler, Christopher John; Yang, Hung-Hsiang; Hong, Jhen-Yong; Hsu, Shih-Hao; Sankar, Raman; Lu, Chun-I; Lu, Hsin-Yu; Yang, Kui-Hon Ou; Shiu, Hung-Wei; Chen, Chia-Hao; Kaun, Chao-Cheng; Shu, Guo-Jiun; Chou, Fang-Cheng; Lin, Minn-Tsong

    2014-01-01

    Surfaces of semiconductors with strong spin-orbit coupling are of great interest for use in spintronic devices exploiting the Rashba effect. BiTeI features large Rashba-type spin splitting in both valence and conduction bands. Either can be shifted towards the Fermi level by surface band bending induced by the two possible polar terminations, making Rashba spin-split electron or hole bands electronically accessible. Here we demonstrate the first real-space microscopic identification of each termination with a multi-technique experimental approach. Using spatially resolved tunnelling spectroscopy across the lateral boundary between the two terminations, a previously speculated on p-n junction-like discontinuity in electronic structure at the lateral boundary is confirmed experimentally. These findings realize an important step towards the exploitation of the unique behaviour of the Rashba semiconductor BiTeI for new device concepts in spintronics. PMID:24898943

  1. Mapping polarization induced surface band bending on the Rashba semiconductor BiTeI.

    PubMed

    Butler, Christopher John; Yang, Hung-Hsiang; Hong, Jhen-Yong; Hsu, Shih-Hao; Sankar, Raman; Lu, Chun-I; Lu, Hsin-Yu; Yang, Kui-Hon Ou; Shiu, Hung-Wei; Chen, Chia-Hao; Kaun, Chao-Cheng; Shu, Guo-Jiun; Chou, Fang-Cheng; Lin, Minn-Tsong

    2014-06-05

    Surfaces of semiconductors with strong spin-orbit coupling are of great interest for use in spintronic devices exploiting the Rashba effect. BiTeI features large Rashba-type spin splitting in both valence and conduction bands. Either can be shifted towards the Fermi level by surface band bending induced by the two possible polar terminations, making Rashba spin-split electron or hole bands electronically accessible. Here we demonstrate the first real-space microscopic identification of each termination with a multi-technique experimental approach. Using spatially resolved tunnelling spectroscopy across the lateral boundary between the two terminations, a previously speculated on p-n junction-like discontinuity in electronic structure at the lateral boundary is confirmed experimentally. These findings realize an important step towards the exploitation of the unique behaviour of the Rashba semiconductor BiTeI for new device concepts in spintronics.

  2. Topography and Mechanical Property Mapping of International Simple Glass Surfaces with Atomic Force Microscopy

    SciTech Connect

    Pierce, Eric M

    2014-01-01

    Quantitative Nanomechanical Peak Force (PF-QNM) TappingModeTM atomic force microscopy measurements are presented for the first time on polished glass surfaces. The PF-QNM technique allows for topography and mechanical property information to be measured simultaneously at each pixel. Results for the international simple glass which represents a simplified version of SON68 glass suggests an average Young s modulus of 78.8 15.1 GPa is within the experimental error of the modulus measured for SON68 glass (83.6 2 GPa) with conventional approaches. Application of the PF-QNM technique will be extended to in situ glass corrosion experiments with the goal of gaining atomic-scale insights into altered layer development by exploiting the mechanical property differences that exist between silica gel (e.g., altered layer) and pristine glass surface.

  3. Mapping the internal recognition surface of an octanuclear coordination cage using guest libraries.

    PubMed

    Turega, Simon; Cullen, William; Whitehead, Martina; Hunter, Christopher A; Ward, Michael D

    2014-06-11

    Size and shape criteria for guest binding inside the cavity of an octanuclear cubic coordination cage in water have been established using a new fluorescence displacement assay to quantify guest binding. For aliphatic cyclic ketones of increasing size (from C5 to C11), there is a linear relationship between ΔG for guest binding and the guest's surface area: the change in ΔG for binding is 0.3 kJ mol(-1) Å(-2), corresponding to 5 kJ mol(-1) for each additional CH2 group in the guest, in good agreement with expectations based on hydrophobic desolvation. The highest association constant is K = 1.2 × 10(6) M(-1) for cycloundecanone, whose volume is approximately 50% of the cavity volume; for larger C12 and C13 cyclic ketones, the association constant progressively decreases as the guests become too large. For a series of C10 aliphatic ketones differing in shape but not size, ΔG for guest binding showed no correlation with surface area. These guests are close to the volume limit of the cavity (cf. Rebek's 55% rule), so the association constant is sensitive to shape complementarity, with small changes in guest structure resulting in large changes in binding affinity. The most flexible members of this series (linear aliphatic ketones) did not bind, whereas the more preorganized cyclic ketones all have association constants of 10(4)-10(5) M(-1). A crystal structure of the cage·cycloundecanone complex shows that the guest carbonyl oxygen is directed into a binding pocket defined by a convergent set of CH groups, which act as weak hydrogen-bond donors, and also shows close contacts between the exterior surface of the disc-shaped guest and the interior surface of the pseudospherical cage cavity despite the slight mismatch in shape.

  4. Mapping land surface emissivity from NDVI: Application to European, African, and South American areas

    SciTech Connect

    Valor, E.; Caselles, V.

    1996-09-01

    Temperature is an important magnitude for many environmental models: (1) energy and matter exchange between atmosphere and surface, (2) weather prediction, (3) global ocean circulation, (4) climatic change, etc. Several methods have been developed to obtain surface emissivity from satellite data. In this way the authors propose a theoretical model that relates the emissivity to the NDVI (normalized difference vegetation index) of a given surface and explains the experimental behavior observed by van de Griend and Owe. They can use it to obtain the emissivity in any thermal channel, but in this work they have focused on the 10.5- to 12.5-{micro}m region, where most thermal sensors on board satellites work at present.The model is applicable to areas with several soil and vegetation types an where the vegetation cover changes. From the theoretical model the authors have developed an operational methodology to obtain the effective emissivity combining satellite images and field measurements.The error of the methodology ranges from 0.5% (due to the experimental limitations of the field methods) to 2% (considering the case in which they have no information about the studied area). To check the general validity of the model, the authors have validated and applied it in different atmospheric environments and in areas with a different degree of roughness, i.e., from midlatitude (France, Argentina) to tropical (Sahel, Botswana) atmospheres, and from flat (La Mancha, Spain) to rough (Valencia, Spain) surfaces, and they have obtained an error of estimate of 0.6% on the emissivity.

  5. Mapping Ocean Surface Topography with a Synthetic-Aperture Interferometry Radar

    NASA Technical Reports Server (NTRS)

    Fu, Lee-Lueng; Rodriguez, Ernesto

    2006-01-01

    We propose to apply the technique of synthetic aperture radar interferometry to the measurement of ocean surface topography at spatial resolution approaching 1 km. The measurement will have wide ranging applications in oceanography, hydrology. and marine geophysics. The oceanographic and related societal applications are briefly discussed in the paper. To meet the requirements for oceanographic applications, the instrument must be flown in an orbit with proper sampling of ocean tides.

  6. Mapping the downwelling atmospheric radiation at the Earth's surface: A research strategy

    NASA Technical Reports Server (NTRS)

    Raschke, E.

    1986-01-01

    A strategy is presented along with background material for determining downward atmospheric radiation at the Earth's surface on a regional scale but over the entire globe, using available information on the temperature and humidity of the air near the ground and at cloud base altitudes. Most of these parameters can be inferred from satellite radiance measurements. Careful validation of the derived radiances will be required using ground-based direct measurements of radiances, to avoid systematic biases of these derived field quantities.

  7. Combining a Spatial Model and Demand Forecasts to Map Future Surface Coal Mining in Appalachia.

    PubMed

    Strager, Michael P; Strager, Jacquelyn M; Evans, Jeffrey S; Dunscomb, Judy K; Kreps, Brad J; Maxwell, Aaron E

    2015-01-01

    Predicting the locations of future surface coal mining in Appalachia is challenging for a number of reasons. Economic and regulatory factors impact the coal mining industry and forecasts of future coal production do not specifically predict changes in location of future coal production. With the potential environmental impacts from surface coal mining, prediction of the location of future activity would be valuable to decision makers. The goal of this study was to provide a method for predicting future surface coal mining extents under changing economic and regulatory forecasts through the year 2035. This was accomplished by integrating a spatial model with production demand forecasts to predict (1 km2) gridded cell size land cover change. Combining these two inputs was possible with a ratio which linked coal extraction quantities to a unit area extent. The result was a spatial distribution of probabilities allocated over forecasted demand for the Appalachian region including northern, central, southern, and eastern Illinois coal regions. The results can be used to better plan for land use alterations and potential cumulative impacts.

  8. Combining a Spatial Model and Demand Forecasts to Map Future Surface Coal Mining in Appalachia

    PubMed Central

    Strager, Michael P.; Strager, Jacquelyn M.; Evans, Jeffrey S.; Dunscomb, Judy K.; Kreps, Brad J.; Maxwell, Aaron E.

    2015-01-01

    Predicting the locations of future surface coal mining in Appalachia is challenging for a number of reasons. Economic and regulatory factors impact the coal mining industry and forecasts of future coal production do not specifically predict changes in location of future coal production. With the potential environmental impacts from surface coal mining, prediction of the location of future activity would be valuable to decision makers. The goal of this study was to provide a method for predicting future surface coal mining extents under changing economic and regulatory forecasts through the year 2035. This was accomplished by integrating a spatial model with production demand forecasts to predict (1 km2) gridded cell size land cover change. Combining these two inputs was possible with a ratio which linked coal extraction quantities to a unit area extent. The result was a spatial distribution of probabilities allocated over forecasted demand for the Appalachian region including northern, central, southern, and eastern Illinois coal regions. The results can be used to better plan for land use alterations and potential cumulative impacts. PMID:26090883

  9. Surface circulation in the Iroise Sea (western Brittany) derived from high resolution current mapping by HF radars

    NASA Astrophysics Data System (ADS)

    Sentchev, Alexei; Forget, Philippe; Barbin, Yves; Marié, Louis; Ardhuin, Fabrice

    2010-05-01

    The use of high frequency radar (HFR) systems for near-real-time coastal ocean monitoring necessities that short time scale motions of the radar-derived velocities are better understood. While the ocean radar systems are able to describe coastal flow patterns with unprecedented details, the data they produce are often too sparse or gappy for applications such as the identification of coherent structures and fronts or understanding transport and mixing processes. In this study, we address two challenges. First, we report results from the HF radar system (WERA) which is routinely operating since 2006 on the western Brittany coast to monitor surface circulation in the Iroise Sea, over an area extending up to 100 km offshore. To obtain more reliable records of vector current fields at high space and time resolution, the Multiple Signal Classification (MUSIC) direction finding algorithm is employed in conjunction with the variational interpolation (2dVar) of radar-derived velocities. This provides surface current maps at 1 km spacing and time resolution of 20 min. Removing the influence of the sea state on radar-derived current measurements is discussed and performed on some data sequences. Second, we examine in deep continuous 2d velocity records for a number of periods, exploring the different modes of variability of surface currents in the region. Given the extent, duration, and resolution of surface current velocity measurements, new quantitative insights from various time series and spatial analysis on higher frequency kinematics will be discussed. By better characterizing the full spectrum of flow regimes that contribute to the surface currents and their shears, a more complete picture of the circulation in the Iroise Sea can be obtained.

  10. Documentation for emergency condition mapping of Decorated historic surfaces at the Caid Residence, the Kasbah of Taourirt (Ouarzazate, Morocco)

    NASA Astrophysics Data System (ADS)

    Percy, K.; Ouimet, C.; Ward, S.; Santana Quintero, M.; Cancino, C.; Wong, L.; Marcus, B.; Whittaker, S.; Boussalh, M.

    2015-08-01

    As it is broadly understood, recording serves as a basis for the diagnosis, treatment and preservation of historic places and contributes to record our built cultural heritage for posterity. This work is not a stand-alone practice but a part of the overall conservation process of cultural heritage at imminent risk of irreversible damage. Recording of heritage places should be directly related to the needs, skills and the technology that are available to the end users that are responsible for the management and care of these sites. They should be selected in a way that the future managers of these sites can also access and use the data collected. This paper explains an innovative heritage recording approach applied by the Getty Conservation Institute (GCI) and Carleton Immersive Media Studio (CIMS) in the documentation of historic decorated surfaces at the Caïd Residence, located at Tighermt (Kasbah) Taourirt in Ouarzazate, Morocco; as part of a collaborative project between the GCI and the Centre de Conservation et Réhabilitation du Patrimoine Architectural des Zones Atlasiques et Sub-Atlasiques (CERKAS) to rehabilitate the entire architectural ensemble. The selected recording techniques were used for the rapid mapping of conditions of the decorated surfaces at the Caïd Residence using international standards. The resulting work is being used by GCI staff, consultants and CERKAS team to conduct emergency stabilization and protection measures for these important decorated surfaces.

  11. Mapping of Bare Soil Surface Parameters (Moisture, Roughness, Texture) from one TerraSAR-X Radar Configuration

    NASA Astrophysics Data System (ADS)

    Zribi, Mehrez; Gorrab, Azza; Baghdadi, Nicolas; Chabaane, Zohra Lili

    2016-08-01

    In this paper, surface bare soil parameters (moisture, roughness and texture) mapping was carried out in central Tunisia (North Africa) using one TerraSAR-X radar configuration (one incidence angle, one polarization). Firstly, we analyzed statistically the relationships between TerraSAR-X backscattering signals function of soil moisture and different roughness parameters (the root mean square height Hrms, the Zs and the Zg parameters) at 36° and HH polarization. Results have shown a high sensitivity of real radar data to all soil parameters. Then, we proposed an algorithm combing the TerraSAR-X images with different continuous thetaprobe measurements for the retrieval of surface soil moisture. Empirical relationship was established between the mean moisture values retrieved from the SAR images and the percentage of clay over 36 test fields. Validation of the proposed approach was carried out over a second set of 34 fields, showing that highly accurate clay estimations can be achieved. Finally, for spatial and temporal surface roughness estimation, we proposed empirical relationships between radar and soil roughness parameters (Hrms and Zg parameters). The proposed model was calibrated over 39 test fields, and then validated over 40 other plots.

  12. Curie isotherm map of Scotia Arc from near surface magnetic anomaly data

    NASA Astrophysics Data System (ADS)

    Catalán, Manuel

    2016-04-01

    The opening of the Drake Passage, situated between South America and Antarctica, represents the final stage of the fragmentation of Gondwana supercontinent. It led to the Scotia Arc formation, bordering the Scotia Sea, which is surrounded by fragments of the former continental connection. It is currently composed of Scotia and Sandwich Plates. Shackleton Fracture Zone constitutes its sinistral transpressive western boundary and it is a key structure that accommodates former Phoenix and Scotia Plates' differential movement. The formation of the Drake Passage and the Scotia Sea is considered of great importance to ocean circulation, as it allows the establishment of the Antarctic Circumpolar Current that isolated the Antarctic continent, with strong implications for climate and global changes. Thermal structure of the Earth's crust is one of the main parameters controlling geodynamic processes. There is few information regarding heat flow values on Scotia arc. These values are mainly located in its westernmost, southern and easternmost part, which are not enough to extract conclusions regarding lithospheric thickness variations and asthenospheric flow. Taking advantage of the World Digital Magnetic Anomaly Map Project's compilation we have extracted magnetic anomaly data which fall inside the Scotia Arc and surrounding areas. This magnetic anomaly picture provides the best representation of magnetic properties to date. We propose to use spectral methods on this regional magnetic compilation to obtain depth to the bottom of magnetic sources as a proxy to infer Curie depth and heat flow distribution in the Scotia Sea.

  13. Surface analysis and mechanical behaviour mapping of vertically aligned CNT forest array through nanoindentation

    NASA Astrophysics Data System (ADS)

    Koumoulos, Elias P.; Charitidis, C. A.

    2017-02-01

    Carbon nanotube (CNT) based architectures have increased the scientific interest owning to their exceptional performance rendering them promising candidates for advanced industrial applications in the nanotechnology field. Despite individual CNTs being considered as one of the most known strong materials, much less is known about other CNT forms, such as CNT arrays, in terms of their mechanical performance (integrity). In this work, thermal chemical vapor deposition (CVD) method is employed to produce vertically aligned multiwall (VA-MW) CNT carpets. Their structural properties were studied by means of scanning electron microscopy (SEM), X-Ray diffraction (XRD) and Raman spectroscopy, while their hydrophobic behavior was investigated via contact angle measurements. The resistance to indentation deformation of VA-MWCNT carpets was investigated through nanoindentation technique. The synthesized VA-MWCNTs carpets consisted of well-aligned MWCNTs. Static contact angle measurements were performed with water and glycerol, revealing a rather super-hydrophobic behavior. The structural analysis, hydrophobic behavior and indentation response of VA-MWCNTs carpets synthesized via CVD method are clearly demonstrated. Additionally, cycle indentation load-depth curve was applied and hysteresis loops were observed in the indenter loading-unloading cycle due to the local stress distribution. Hardness (as resistance to applied load) and modulus mapping, at 200 nm of displacement for a grid of 70 μm2 is presented. Through trajection, the resistance is clearly divided in 2 regions, namely the MWCNT probing and the in-between area MWCNT - MWCNT interface.

  14. Mapping Deep Low Velocity Zones in Alaskan Arctic Coastal Permafrost using Seismic Surface Waves

    NASA Astrophysics Data System (ADS)

    Dou, S.; Ajo Franklin, J. B.; Dreger, D. S.

    2012-12-01

    Permafrost degradation may be an important amplifier of climate change; Thawing of near-surface sediments holds the potential of increasing greenhouse gas emissions due to microbial decomposition of preserved organic carbon. Recently, the characterization of "deep" carbon pools (several meters below the surface) in circumpolar frozen ground has increased the estimated amount of soil carbon to three times higher than what was previously thought. It is therefore potentially important to include the characteristics and processes of deeper permafrost strata (on the orders of a few to tens of meters below surface) in climate models for improving future predictions of accessible carbon and climate feedbacks. This extension is particularly relevant if deeper formations are not completely frozen and may harbor on-going microbial activity despite sub-zero temperatures. Unfortunately, the characterization of deep permafrost systems is non-trivial; logistics and drilling constraints often limit direct characterization to relatively shallow units. Geophysical measurements, either surface or airborne, are often the most effective tools for evaluating these regions. Of the available geophysical techniques, the analysis of seismic surface waves (e.g. MASW) has several unique advantages, mainly the ability to provide field-scale information with good depth resolution as well as penetration (10s to 100s of m with small portable sources). Surface wave methods are also able to resolve low velocity regions, a class of features that is difficult to characterize using traditional P-wave refraction methods. As part of the Department of Energy (DOE) Next-Generation Ecosystem Experiments (NGEE-Arctic) project, we conducted a three-day seismic field survey (May 12 - 14, 2012) at the Barrow Environmental Observatory, which is located within the Alaskan Arctic Coastal Plain. Even though permafrost at the study site is continuous, ice-rich and thick (>= 350m), our Multichannel Analysis of

  15. Geologic mapping of near-surface sediments in the northern Mississippi Embayment, McCracken County, KY

    SciTech Connect

    Sexton, Joshua L; Fryar, Alan E; Greb, s F

    2006-04-01

    POSTER: The Jackson Purchase region of western Kentucky consists of Coastal Plain sediments near the northern margin of the Mississippi Embayment. Within this region is the Paducah Gaseous Diffusion Plant (PGDP), a uranium enrichment facility operated by the US Department of Energy. At PGDP, a Superfund site, soil and groundwater studies have provided subsurface lithologic data from hundreds of monitoring wells and borings. Despite preliminary efforts by various contractors, these data have not been utilized to develop detailed stratigraphic correlations of sedimentary units across the study area. In addition, sedimentary exposures along streams in the vicinityof PGDP have not been systematically described beyond the relatively simple geologic quadrangle maps published by the US Geological Survey in 1966-67. This study integrates lithologic logs, other previous site investigation data, and outcrop mapping to provide a compilation of near-surface lithologic and stratigraphic data for the PGDP area. A database of borehole data compiled during this study has been provided to PGDP for future research and archival.

  16. Three-body Coulomb problem probed by mapping the Bethe surface in ionizing ion-atom collisions.

    PubMed

    Moshammer, R; Perumal, A; Schulz, M; Rodríguez, V D; Kollmus, H; Mann, R; Hagmann, S; Ullrich, J

    2001-11-26

    The three-body Coulomb problem has been explored in kinematically complete experiments on single ionization of helium by 100 MeV/u C(6+) and 3.6 MeV/u Au(53+) impact. Low-energy electron emission ( E(e)<150 eV) as a function of the projectile deflection theta(p) (momentum transfer), i.e., the Bethe surface [15], has been mapped with Delta theta(p)+/-25 nanoradian resolution at extremely large perturbations ( 3.6 MeV/u Au(53+)) where single ionization occurs at impact parameters of typically 10 times the He K-shell radius. The experimental data are not in agreement with state-of-the-art continuum distorted wave-eikonal initial state theory.

  17. Near-surface mapping using SH-wave and P-wave seismic land-streamer data acquisition in Illinois, U.S

    USGS Publications Warehouse

    Pugin, Andre J.M.; Larson, T.H.; Sargent, S.L.; McBride, J.H.; Bexfield, C.E.

    2004-01-01

    SH-wave and P-wave high-resolution seismic reflection combined with land-streamer technology provide 3D regional maps of geologic formations that can be associated with aquifers and aquitards. Examples for three study areas are considered to demonstrate this. In these areas, reflection profiling detected near-surface faulting and mapped a buried glacial valley and its aquifers in two settings. The resulting seismic data can be used directly to constrain hydrogeologic modeling of shallow aquifers.

  18. Global land surface albedo maps from MODIS using the Google Earth Engine

    NASA Astrophysics Data System (ADS)

    Mitraka, Zina; Benas, Nikolaos; Gorelick, Noel; Chrysoulakis, Nektarios

    2016-04-01

    The land surface albedo (LSA) is a critical physical variable, which influences the Earth's climate by affecting the energy budget and distribution in the Earth-atmosphere system. Its role is highly significant in both global and local scales; hence, LSA measurements provide a quantitative means for better constraining global and regional scale climate modelling efforts. The Moderate Resolution Imaging Spectroradiometer (MODIS) sensor, on board NASA's Terra and Aqua platforms, provides the parameters needed for the computation of LSA on an 8-day temporal scale and a variety of spatial scales (ranging between 0.5 - 5 km). This dataset was used here for the LSA estimation and its changes over the study area at 0.5 km spatial resolution. More specifically, the MODIS albedo product was used, which includes both the directional-hemispherical surface reflectance (black-sky albedo) and the bi-hemispherical surface reflectance (white-sky albedo). The LSA was estimated for the whole globe on an 8-day basis for the whole time period covered by MODIS acquisitions (i.e. 2000 until today). To estimate LSA from black-sky and white-sky albedos, the fraction of the diffused radiation is needed, a function of the Aerosol Optical Thickness (AOT). Required AOT information was acquired from the MODIS AOT product at 1̊ × 1̊ spatial resolution. Since LSA also depends on solar zenith angle (SZA), 8-day mean LSA values were computed as averages of corresponding LSA values for representative SZAs covering the 24-hour day. The estimated LSA was analysed in terms of both spatial and seasonal characteristics, while LSA changes during the period examined were assessed. All computation were performed using the Google Earth Engine (GEE). The GEE provided access to all the MODIS products needed for the analysis without the need of searching or downloading. Moreover, the combination of MODIS products in both temporal and spatial terms was fast and effecting using the GEE API (Application

  19. A three dimensional Dirichlet-to-Neumann map for surface waves over topography

    NASA Astrophysics Data System (ADS)

    Nachbin, Andre; Andrade, David

    2016-11-01

    We consider three dimensional surface water waves in the potential theory regime. The bottom topography can have a quite general profile. In the case of linear waves the Dirichlet-to-Neumann operator is formulated in a matrix decomposition form. Computational simulations illustrate the performance of the method. Two dimensional periodic bottom variations are considered in both the Bragg resonance regime as well as the rapidly varying (homogenized) regime. In the three-dimensional case we use the Luneburg lens-shaped submerged mound, which promotes the focusing of the underlying rays. FAPERJ Cientistas do Nosso Estado Grant 102917/2011 and ANP/PRH-32.

  20. Mapping ground surface deformation using temporarily coherent point SAR interferometry: Application to Los Angeles Basin

    USGS Publications Warehouse

    Zhang, L.; Lu, Zhiming; Ding, X.; Jung, H.-S.; Feng, G.; Lee, C.-W.

    2012-01-01

    Multi-temporal interferometric synthetic aperture radar (InSAR) is an effective tool to detect long-term seismotectonic motions by reducing the atmospheric artifacts, thereby providing more precise deformation signal. The commonly used approaches such as persistent scatterer InSAR (PSInSAR) and small baseline subset (SBAS) algorithms need to resolve the phase ambiguities in interferogram stacks either by searching a predefined solution space or by sparse phase unwrapping methods; however the efficiency and the success of phase unwrapping cannot be guaranteed. We present here an alternative approach - temporarily coherent point (TCP) InSAR (TCPInSAR) - to estimate the long term deformation rate without the need of phase unwrapping. The proposed approach has a series of innovations including TCP identification, TCP network and TCP least squares estimator. We apply the proposed method to the Los Angeles Basin in southern California where structurally active faults are believed capable of generating damaging earthquakes. The analysis is based on 55 interferograms from 32 ERS-1/2 images acquired during Oct. 1995 and Dec. 2000. To evaluate the performance of TCPInSAR on a small set of observations, a test with half of interferometric pairs is also performed. The retrieved TCPInSAR measurements have been validated by a comparison with GPS observations from Southern California Integrated GPS Network. Our result presents a similar deformation pattern as shown in past InSAR studies but with a smaller average standard deviation (4.6. mm) compared with GPS observations, indicating that TCPInSAR is a promising alternative for efficiently mapping ground deformation even from a relatively smaller set of interferograms. ?? 2011.

  1. Pole Photogrammetry with AN Action Camera for Fast and Accurate Surface Mapping

    NASA Astrophysics Data System (ADS)

    Gonçalves, J. A.; Moutinho, O. F.; Rodrigues, A. C.

    2016-06-01

    High resolution and high accuracy terrain mapping can provide height change detection for studies of erosion, subsidence or land slip. A UAV flying at a low altitude above the ground, with a compact camera, acquires images with resolution appropriate for these change detections. However, there may be situations where different approaches may be needed, either because higher resolution is required or the operation of a drone is not possible. Pole photogrammetry, where a camera is mounted on a pole, pointing to the ground, is an alternative. This paper describes a very simple system of this kind, created for topographic change detection, based on an action camera. These cameras have high quality and very flexible image capture. Although radial distortion is normally high, it can be treated in an auto-calibration process. The system is composed by a light aluminium pole, 4 meters long, with a 12 megapixel GoPro camera. Average ground sampling distance at the image centre is 2.3 mm. The user moves along a path, taking successive photos, with a time lapse of 0.5 or 1 second, and adjusting the speed in order to have an appropriate overlap, with enough redundancy for 3D coordinate extraction. Marked ground control points are surveyed with GNSS for precise georeferencing of the DSM and orthoimage that are created by structure from motion processing software. An average vertical accuracy of 1 cm could be achieved, which is enough for many applications, for example for soil erosion. The GNSS survey in RTK mode with permanent stations is now very fast (5 seconds per point), which results, together with the image collection, in a very fast field work. If an improved accuracy is needed, since image resolution is 1/4 cm, it can be achieved using a total station for the control point survey, although the field work time increases.

  2. A Tetrahedron-Based Endmember Selection Approach for Urban Impervious Surface Mapping

    PubMed Central

    Wang, Wei; Yao, Xinfeng; Zhai, Junpeng; Ji, Minhe

    2014-01-01

    The pixel purity index (PPI) and two-dimensional (2-D) scatter plots are two popular techniques for endmember extraction in remote sensing spectral mixture analysis, yet both suffer from one major drawback, that is, the selection of a final set of endmembers has to endure a cumbersome process of iterative visual inspection and human intervention, especially when a spectrally-complex urban scene is involved. Within the conceptual framework of a V-H-L-S (vegetation-high albedo-low albedo-soil) model, which is expanded from the classic V-I-S (vegetation-impervious surface-soil) model, a tetrahedron-based endmember selection approach combined with a multi-objective optimization genetic algorithm (MOGA) was designed to identify urban endmembers from multispectral imagery. The tetrahedron defining the enclosing volume of MNF-transformed pixels in a three-dimensional (3-D) space was algorithmically sought, so that the tetrahedral vertices can ideally match the four components of the adopted model. A case study with Landsat Enhanced Thematic Mapper Plus (ETM+) satellite imagery in Shanghai, China was conducted to verify the validity of the method. The method performance was compared with those of the traditional PPI and 2-D scatter plots approaches. The results indicated that the tetrahedron-based endmember selection approach performed better in both accuracy and ease of identification for urban surface endmembers owing to the 3-D visualization analysis and use of the MOGA. PMID:24892938

  3. A tetrahedron-based endmember selection approach for urban impervious surface mapping.

    PubMed

    Wang, Wei; Yao, Xinfeng; Zhai, Junpeng; Ji, Minhe

    2014-01-01

    The pixel purity index (PPI) and two-dimensional (2-D) scatter plots are two popular techniques for endmember extraction in remote sensing spectral mixture analysis, yet both suffer from one major drawback, that is, the selection of a final set of endmembers has to endure a cumbersome process of iterative visual inspection and human intervention, especially when a spectrally-complex urban scene is involved. Within the conceptual framework of a V-H-L-S (vegetation-high albedo-low albedo-soil) model, which is expanded from the classic V-I-S (vegetation-impervious surface-soil) model, a tetrahedron-based endmember selection approach combined with a multi-objective optimization genetic algorithm (MOGA) was designed to identify urban endmembers from multispectral imagery. The tetrahedron defining the enclosing volume of MNF-transformed pixels in a three-dimensional (3-D) space was algorithmically sought, so that the tetrahedral vertices can ideally match the four components of the adopted model. A case study with Landsat Enhanced Thematic Mapper Plus (ETM+) satellite imagery in Shanghai, China was conducted to verify the validity of the method. The method performance was compared with those of the traditional PPI and 2-D scatter plots approaches. The results indicated that the tetrahedron-based endmember selection approach performed better in both accuracy and ease of identification for urban surface endmembers owing to the 3-D visualization analysis and use of the MOGA.

  4. Neutron-induced gamma-ray spectroscopy: simulations for chemical mapping of planetary surfaces

    SciTech Connect

    Brueckner, J.; Waenke, H.; Reedy, R.C.

    1986-01-01

    Cosmic rays interact with the surface of a planetary body and produce a cascade of secondary particles, such as neutrons. Neutron-induced scattering and capture reactions play an important role in the production of discrete gamma-ray lines that can be measured by a gamma-ray spectrometer on board of an orbiting spacecraft. These data can be used to determine the concentration of many elements in the surface of a planetary body, which provides clues to its bulk composition and in turn to its origin and evolution. To investigate the gamma rays made by neutron interactions, thin targets were irradiated with neutrons having energies from 14 MeV to 0.025 eV. By means of foil activation technique the ratio of epithermal to thermal neutrons was determined to be similar to that in the Moon. Gamma rays emitted by the targets and the surrounding material were detected by a high-resolution germanium detector in the energy range of 0.1 to 8 MeV. Most of the gamma-ray lines that are expected to be used for planetary gamma-ray spectroscopy were found in the recorded spectra and the principal lines in these spectra are presented. 58 refs., 7 figs., 9 tabs.

  5. Simulation experiments for gamma-ray mapping of planetary surfaces: Scattering of high-energy neutrons

    NASA Technical Reports Server (NTRS)

    Brueckner, J.; Englert, P.; Reedy, R. C.; Waenke, H.

    1986-01-01

    The concentration and distribution of certain elements in surface layers of planetary objects specify constraints on models of their origin and evolution. This information can be obtained by means of remote sensing gamma-ray spectroscopy, as planned for a number of future space missions, i.e., Mars, Moon, asteroids, and comets. To investigate the gamma-rays made by interactions of neutrons with matter, thin targets of different composition were placed between a neutron-source and a high-resolution germanium spectrometer. Gamma-rays in the range of 0.1 to 8 MeV were accumulated. In one set of experiments a 14-MeV neutron generator using the T(d,n) reaction as neutron-source was placed in a small room. Scattering in surrounding walls produced a spectrum of neutron energies from 14 MeV down to thermal. This complex neutron-source induced mainly neutron-capture lines and only a few scattering lines. As a result of the set-up, there was a considerable background of discrete lines from surrounding materials. A similar situation exists under planetary exploration conditions: gamma-rays are induced in the planetary surface as well as in the spacecraft. To investigate the contribution of neutrons with higher energies, an experiment for the measurement of prompt gamma radiation was set up at the end of a beam-line of an isochronous cyclotron.

  6. Image system for three dimensional, 360 DEGREE, time sequence surface mapping of moving objects

    DOEpatents

    Lu, Shin-Yee

    1998-01-01

    A three-dimensional motion camera system comprises a light projector placed between two synchronous video cameras all focused on an object-of-interest. The light projector shines a sharp pattern of vertical lines (Ronchi ruling) on the object-of-interest that appear to be bent differently to each camera by virtue of the surface shape of the object-of-interest and the relative geometry of the cameras, light projector and object-of-interest Each video frame is captured in a computer memory and analyzed. Since the relative geometry is known and the system pre-calibrated, the unknown three-dimensional shape of the object-of-interest can be solved for by matching the intersections of the projected light lines with orthogonal epipolar lines corresponding to horizontal rows in the video camera frames. A surface reconstruction is made and displayed on a monitor screen. For 360.degree. all around coverage of theobject-of-interest, two additional sets of light projectors and corresponding cameras are distributed about 120.degree. apart from one another.

  7. Image system for three dimensional, 360{degree}, time sequence surface mapping of moving objects

    DOEpatents

    Lu, S.Y.

    1998-12-22

    A three-dimensional motion camera system comprises a light projector placed between two synchronous video cameras all focused on an object-of-interest. The light projector shines a sharp pattern of vertical lines (Ronchi ruling) on the object-of-interest that appear to be bent differently to each camera by virtue of the surface shape of the object-of-interest and the relative geometry of the cameras, light projector and object-of-interest. Each video frame is captured in a computer memory and analyzed. Since the relative geometry is known and the system pre-calibrated, the unknown three-dimensional shape of the object-of-interest can be solved for by matching the intersections of the projected light lines with orthogonal epipolar lines corresponding to horizontal rows in the video camera frames. A surface reconstruction is made and displayed on a monitor screen. For 360{degree} all around coverage of the object-of-interest, two additional sets of light projectors and corresponding cameras are distributed about 120{degree} apart from one another. 20 figs.

  8. Mapping the environmental risk potential on surface water of pesticide contamination in the Prosecco's vineyard terraced landscape

    NASA Astrophysics Data System (ADS)

    Pizarro, Patricia; Ferrarese, Francesco; Loddo, Donato; Eugenio Pappalardo, Salvatore; Varotto, Mauro

    2016-04-01

    Intensive cropping systems today represent a paramount issue in terms of environmental impacts, since agricultural pollutants can constitute a potential threat to surface water, non-target organisms and aquatic ecosystems. Levels of pesticide concentrations in surface waters are indeed unquestionably correlated to crop and soil management practices at field-scale. Due to the numerous applications of pesticides required, orchards and vineyards can represent relevant non-point sources for pesticide contamination of water bodies, mainly prompted by soil erosion, surface runoff and spray drift. To reduce risks of pesticide contamination of surface water, the Directive 2009/128/CET imposed the local implementation of agricultural good practices and mitigation actions such as the use of vegetative buffer filter strips and hedgerows along river and pond banks. However, implementation of mitigation actions is often difficult, especially in extremely fragmented agricultural landscapes characterized by a complex territorial matrix set up on urban sprawling, frequent surface water bodies, important geomorphological processes and protected natural areas. Typically, such landscape matrix is well represented by the, Prosecco-DOCG vineyards area (NE of Italy, Province of Treviso) which lays on hogback hills of conglomerate, marls and sandstone that ranges between 50 and 500 m asl. Moreover such vineyards landscape is characterized by traditional and non-traditional agricultural terraces The general aim of this paper is to identify areas of surface water bodies with high potential risk of pesticide contamination from surrounding vineyards in the 735 ha of Lierza river basin (Refrontolo, TV), one of the most representative terraced landscape of the Prosecco-DOCG area. Specific aims are i) mapping terraced Prosecco-DOCG vineyards, ii) classifying potential risk from pesticide of the different areas. Remote sensing technologies such as four bands aerial photos (RGB+NIR) and Light

  9. Road-mapping the Way Forward for Sentinel-3 Topography Mission SAR-Mode waveform Retracking over water surfaces

    NASA Astrophysics Data System (ADS)

    Benveniste, Jérôme; Gommenginger, Christine; Dinardo, Salvatore; Martin-Puig, MCristina; Lucas, Bruno Manuel; Cotton, David; Ray, Chris

    2012-07-01

    In the framework of the ESA SAMOSA Project (SAR Altimetry Studies and Applications over Ocean, Coastal zones and Inland waters), innovative physically based models have been developed for near-nadir ocean altimetric waveforms in SAR-Mode and subsequently implemented in prototype ocean SAR retrackers. In this paper, we present the approach used to date within SAMOSA and the heritage behind the latest SAMOSA2 model. The SAMOSA2 model offers a complete description of SAR altimeter Echoes from ocean surfaces, expressed in the form of maps of reflected power in delay and Doppler space. SAMOSA2 is able to account for an elliptical antenna pattern, mispointing errors in elevation and azimuth, errors in range cell migration correction, surface scattering pattern, non-linear ocean wave statistics and spherical Earth surface effects. SAMOSA2 addresses some of the known limitations of the earlier SAMOSA1 model, in particular with regards to sensitivity to mispointing. Due to its truly comprehensive character, the full SAMOSA2 model is a complicated semi-analytical formulation that still relies on some numerical integrations. The need for numerical integrations negatively impacts the computation time and raises problems of numerical stability once implemented operationally in a re-tracker scheme. This has potentially serious implications that could prevent future implementation of SAMOSA2 in operational re-tracker schemes for future SAR altimeters. However, since the ultimate goal of the SAMOSA project is to deliver to the Sentinel-3 Surface Topography Mission Product and Algorithm Development (S-3 STM PAD) a Detailed Processing Model of a SAR ocean waveform re-tracker based on the best SAMOSA model to operationally retrack Sentinel-3 STM SAR-Mode L1b waveforms, the need for the full mathematical complexity of the SAMOSA2 model is currently being evaluated. With this in mind, the SAMOSA team is assessing a number of simplifications that can transform the SAMOSA2 model into an

  10. Hydrogeology, groundwater levels, and generalized potentiometric-surface map of the Green River Basin lower Tertiary aquifer system, 2010–14, in the northern Green River structural basin

    USGS Publications Warehouse

    Bartos, Timothy T.; Hallberg, Laura L.; Miller, Cheryl E.

    2015-07-14

    The groundwater-level measurements were used to construct a generalized potentiometric-surface map of the Green River Basin lower Tertiary aquifer system. Groundwater-level altitudes measured in nonflowing and flowing wells used to construct the potentiometric-surface map ranged from 6,451 to 7,307 feet (excluding four unmeasured flowing wells used for contour construction purposes). The potentiometric-surface map indicates that groundwater in the study area generally moves from north to south, but this pattern of flow is altered locally by groundwater divides, groundwater discharge to the Green River, and possibly to a tributary river (Big Sandy River) and two reservoirs (Fontenelle and Big Sandy Reservoirs).

  11. Multispectral mapping of the lunar surface using ground-based telescopes

    NASA Technical Reports Server (NTRS)

    Mccord, T. B.; Feierberg, M. A.; Pieters, C.

    1976-01-01

    Images of the lunar surface were obtained at several wavelengths using a silicon vidicon imaging system and ground-based telescopes. These images were recorded and processed in digital form so that quantitative information was preserved. The photometric precision of the images is shown to be better than 1%. Ratio images calculated by dividing images obtained at two wavelengths (0.40/0.56 and 0.95/0.56 microns) are presented for about 50% of the lunar frontside. Spatial resolution is about 2 km at the subearth point. A complex of distinct units is evident in the images. Earlier work with the reflectance spectrum of lunar materials indicates that, for the most part, these units are compositionally distinct.

  12. Surface Current Density Mapping for Identification of Gastric Slow Wave Propagation

    PubMed Central

    Bradshaw, L. A.; Cheng, L. K.; Richards, W. O.; Pullan, A. J.

    2009-01-01

    The magnetogastrogram records clinically relevant parameters of the electrical slow wave of the stomach noninvasively. Besides slow wave frequency, gastric slow wave propagation 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 propagation velocity of the gastric slow wave. 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 propagation velocity, more detailed information about spatial variations in propagation velocity requires higher density magnetometer arrays. Finally, the method is validated with simultaneous MGG and serosal EMG measurements in a porcine subject. PMID:19403355

  13. Chemical Schemes for Surface Modification of Icy Satellites: A Road Map

    NASA Technical Reports Server (NTRS)

    Delitsky, Mona L.; Lane, Arthur L.

    1997-01-01

    The icy Galilean satellites of Jupiter are subject to magnetospheric plasma ion bombardment, which induces chemical changes within the ice. The possible detection of CO2 on the surface of Ganymede by the Galileo spacecraft makes for a more complicated chemistry and increases the number of chemical compounds that may then be present. We outline chemical schemes for the irradiation of pure and mixed ices H2O/CO2 and suggest species which observers may detect on Europa, Ganymede, and Callisto, such as C3O2, H2CO3, H2O2, CO3, HO2, CO, H2CO, CH2CO, as well as K2O, KOH, and SO3, from plasma implantation. Column abundances of compounds in the ice are calculated using a specified energy input and G values (yield per 100 eV).

  14. Retinotopic Maps, Spatial Tuning, and Locations of Human Visual Areas in Surface Coordinates Characterized with Multifocal and Blocked fMRI Designs

    PubMed Central

    Henriksson, Linda; Karvonen, Juha; Salminen-Vaparanta, Niina; Railo, Henry; Vanni, Simo

    2012-01-01

    The localization of visual areas in the human cortex is typically based on mapping the retinotopic organization with functional magnetic resonance imaging (fMRI). The most common approach is to encode the response phase for a slowly moving visual stimulus and to present the result on an individual's reconstructed cortical surface. The main aims of this study were to develop complementary general linear model (GLM)-based retinotopic mapping methods and to characterize the inter-individual variability of the visual area positions on the cortical surface. We studied 15 subjects with two methods: a 24-region multifocal checkerboard stimulus and a blocked presentation of object stimuli at different visual field locations. The retinotopic maps were based on weighted averaging of the GLM parameter estimates for the stimulus regions. In addition to localizing visual areas, both methods could be used to localize multiple retinotopic regions-of-interest. The two methods yielded consistent retinotopic maps in the visual areas V1, V2, V3, hV4, and V3AB. In the higher-level areas IPS0, VO1, LO1, LO2, TO1, and TO2, retinotopy could only be mapped with the blocked stimulus presentation. The gradual widening of spatial tuning and an increase in the responses to stimuli in the ipsilateral visual field along the hierarchy of visual areas likely reflected the increase in the average receptive field size. Finally, after registration to Freesurfer's surface-based atlas of the human cerebral cortex, we calculated the mean and variability of the visual area positions in the spherical surface-based coordinate system and generated probability maps of the visual areas on the average cortical surface. The inter-individual variability in the area locations decreased when the midpoints were calculated along the spherical cortical surface compared with volumetric coordinates. These results can facilitate both analysis of individual functional anatomy and comparisons of visual cortex topology

  15. Multi-Wavelength, Multi-Beam, and Polarization-Sensitive Laser Transmitter for Surface Mapping

    NASA Technical Reports Server (NTRS)

    Yu, Anthony W.; Ramos-Izquierdo, Luis; Harding, David; Huss, Tim

    2011-01-01

    A multi-beam, multi-color, polarized laser transmitter has been developed for mapping applications. It uses commercial off-the-shelf components for a lowcost approach for a ruggedized laser suitable for field deployment. The laser transmitter design is capable of delivering dual wavelengths, multiple beams on each wavelength with equal (or variable) intensities per beam, and a welldefined state of polarization. This laser transmitter has been flown on several airborne campaigns for the Slope Imaging Multi-Polarization Photon Counting Lidar (SIMPL) instrument, and at the time of this reporting is at a technology readiness level of between 5 and 6. The laser is a 1,064-nm microchip high-repetition-rate laser emitting energy of about 8 microjoules per pulse. The beam was frequency-doubled to 532 nm using a KTP (KTiOPO4) nonlinear crystal [other nonlinear crystals such as LBO (LiB3O5) or periodically poled lithium niobiate can be used as well, depending on the conversion efficiency requirements], and the conversion efficiency was approximately 30 percent. The KTP was under temperature control using a thermoelectric cooler and a feedback monitoring thermistor. The dual-wavelength beams were then spectrally separated and each color went through its own optical path, which consisted of a beam-shaping lens, quarterwave plate (QWP), and a birefringent crystal (in this case, a calcite crystal, but others such as vanadate can be used). The QWP and calcite crystal set was used to convert the laser beams from a linearly polarized state to circularly polarized light, which when injected into a calcite crystal, will spatially separate the circularly polarized light into the two linear polarized components. The spatial separation of the two linearly polarized components is determined by the length of the crystal. A second set of QWP and calcite then further separated the two beams into four. Additional sets of QWP and calcite can be used to further split the beams into multiple

  16. Specific Conductivity Synoptic Surveys to Map Groundwater-Surface Water Discharges in a Lowland River

    NASA Astrophysics Data System (ADS)

    Pai, H.; Villamizar, S. R.; Harmon, T. C.

    2014-12-01

    Quantifying distributed groundwater-surface water (GW-SW) discharges at the watershed scale is a challenging but important aspect of tracking nonpoint-source pollutants and their potential impacts on riverine water quality. This work analyzes high spatiotemporal longitudinal river sampling along a 38 km reach of the lower Merced River (LMR) in California's San Joaquin River (SJR) watershed and estimates GW-SW discharges using a simple discretized mixing model. The LMR flow is dam-controlled upstream and has several distributed surface discharges from SW diversions, SW canal inputs, and potential GW discharges influenced by the surrounding agricultural and municipal landscapes. We collected longitudinal datasets covering a wide range of flows (1.3 to 150 m3/s), sampling georeferenced water specific conductance (SC) at intervals of less than 1 minute. Whole-reach gradients of SW specific conductance (SC), representing GW-SW salinity loading (mS/cm/river km), decreased in proportion to the flow and stage, indicating either (1) a simple dilution effect or (2) reduced GW-SW discharges due to a reduced GW-SW hydraulic gradient at higher stages. With respect to distributed discharges, local gradients were significant (p < 0.05), with estimated local salinity loads varying from -0.4 to 8.9 mS/cm/river km for the LMR conditions. Using local groundwater salinity estimates, we inverted a discretized mixing model to estimate distributed groundwater fluxes. Summation of the fluxes agreed well with stream gage estimates. However, local flux estimates were nonuniform, with mid-reach values consistently increasing to a maximum value at intermediate stream flows, then decreasing for greater flows. Causes for this behavior remain uncertain but may be due to one or more of the following: (1) uncertainty in the groundwater salinity data, (2) salinity reduction in the hyporheic zone (e.g., denitrification), and (3) access to preferential GW-SW flowpaths at intermediate flows and stages

  17. Experimental Approach to Controllably Vary Protein Oxidation While Minimizing Electrode Adsorption for Boron-Doped Diamond Electrochemical Surface Mapping Applications

    SciTech Connect

    McClintock, Carlee; Hettich, Robert {Bob} L

    2013-01-01

    Oxidative protein surface mapping has become a powerful approach for measuring the solvent accessibility of folded protein structures. A variety of techniques exist for generating the key reagent hydroxyl radicals for these measurements; however, many of these approaches require use of radioactive sources or caustic oxidizing chemicals. The purpose of this research was to evaluate and optimize the use of boron-doped diamond (BDD) electrochemistry as a highly accessible tool for producing hydroxyl radicals as a means to induce a controllable level of oxidation on a range of intact proteins. These experiments utilize a relatively high flow rates to reduce protein residence time inside the electrochemical flow chamber, along with a unique cell activation approach to improve control over the intact protein oxidation yield. Studies were conducted to evaluate the level of protein adsorption onto the electrode surface. This report demonstrates a robust protocol for the use of BDD electrochemistry and high performance LC-MS/MS as a high-throughput experimental pipeline for probing higher order protein structure, and illustrates how it is complementary to predictive computational modeling efforts.

  18. Bias correction of global and regional simulated daily precipitation and surface mean temperature over Southeast Asia using quantile mapping method

    NASA Astrophysics Data System (ADS)

    Ngai, Sheau Tieh; Tangang, Fredolin; Juneng, Liew

    2017-02-01

    A trend preserving quantile mapping (QM) method was applied to adjust the biases of the global and regional climate models (GCM and RCMs) simulated daily precipitation and surface mean temperature over Southeast Asia regions based on APHRODITE dataset. Output from four different RCMs as well as their driving GCM in CORDEX-EA archive were corrected to examine the added value of RCMs dynamical downscaling in the context of bias adjustment. The result shows that the RCM biases are comparable to that of the GCM biases. In some instances, RCMs amplified the GCM biases. Generally, QM method substantially improves the biases for both precipitation and temperature. However, the bias adjustment method works better for surface mean temperature and less so for daily precipitation. The large inter-models variability is reduced remarkably after bias adjustment. Overall, study indicates no strong evident that RCMs downscaling as an immediate step before bias correction provides additional improvement to the sub-regional climate compared to the correction directly carried out on their forcing GCM.

  19. Axial Surface Mapping of Wrinkle Ridges on Solis Planum, Mars from MOLA Topography: Constraints on Subsurface Blind Thrust Geometry

    NASA Technical Reports Server (NTRS)

    Vidal, A.; Mueller, K.; Golombek, M. P.

    2003-01-01

    We undertook axial surface mapping of selected wrinkle ridges on Solis Planum, Mars in order to assess the subsurface geometry of blind thrusts proposed to exist beneath them. This work builds on previous work that defined structural families of wrinkle ridges based on their surface morphology in this region. Although a growing consensus exists for models of wrinkle ridge kinematics and mechanics, a number of current problems remain. These include the origin of topographic offset across the edges of wrinkle ridges, the relationship between broad arches and superposed ridges, the origin of smaller wrinkles, and perhaps most importantly, the trajectory of blind thrusts that underlie wrinkle ridges and accommodate shortening at deeper crustal levels. We are particularly interested in defining the depths at which blind thrusts flatten under wrinkle ridges in order to provide constraints on the brittle-ductile transition during Early Hesperian time. We also seek to test whether wrinkle ridges on Solis Planum develop above reactivated faults or newly formed ones.

  20. Localization of the site of origin of reentrant arrhythmia from body surface potential maps: a model study

    NASA Astrophysics Data System (ADS)

    Liu, Chenguang; Li, Guanglin; He, Bin

    2005-04-01

    We have developed a model-based imaging approach to estimate the site of origin of reentrant arrhythmia from body surface potential maps (BSPMs), with the aid of a cardiac arrhythmia model. The reentry was successfully simulated and maintained in the cardiac model, and the simulated ECG waveforms over the body surface corresponding to a maintained reentry have evident characteristics of ventricular tachycardia. The performance of the inverse imaging approach was evaluated by computer simulations. The present simulation results show that an averaged localization error of about 1.5 mm, when 5% Gaussian white noise was added to the BSPMs, was detected. The effects of the heart-torso geometry uncertainty on the localization were also initially assessed and the simulation results suggest that no significant influence was observed when 10% torso geometry uncertainty or 10 mm heart position shifting was considered. The present simulation study suggests the feasibility of localizing the site of origin of reentrant arrhythmia from non-invasive BSPMs, with the aid of a cardiac arrhythmia model.

  1. Deciphering the stepwise binding mode of HRG1β to HER3 by surface plasmon resonance and interaction map.

    PubMed

    Peess, Carmen; von Proff, Leopold; Goller, Sabine; Andersson, Karl; Gerg, Michael; Malmqvist, Magnus; Bossenmaier, Birgit; Schräml, Michael

    2015-01-01

    For the development of efficient anti-cancer therapeutics against the HER receptor family it is indispensable to understand the mechanistic model of the HER receptor activation upon ligand binding. Due to its high complexity the binding mode of Heregulin 1 beta (HRG1β) with its receptor HER3 is so far not understood. Analysis of the interaction of HRG1β with surface immobilized HER3 extracellular domain by time-resolved Surface Plasmon Resonance (SPR) was so far not interpretable using any regular analysis method as the interaction was highly complex. Here, we show that Interaction Map (IM) made it possible to shed light on this interaction. IM allowed deciphering the rate limiting kinetic contributions from complex SPR sensorgrams and thereby enabling the extraction of discrete kinetic rate components from the apparently heterogeneous interactions. We could resolve details from the complex avidity-driven binding mode of HRG1β with HER3 by using a combination of SPR and IM data. Our findings contribute to the general understanding that a major conformational change of HER3 during its activation is induced by a complex sequential HRG1β docking mode.

  2. US EPA 2012 Air Quality Fused Surface for the Conterminous U.S. Map Service

    EPA Pesticide Factsheets

    This web service contains a polygon layer that depicts fused air quality predictions for 2012 for census tracts in the conterminous United States. Fused air quality predictions (for ozone and PM2.5) are modeled using a Bayesian space-time downscaling fusion model approach described in a series of three published journal papers: 1) (Berrocal, V., Gelfand, A. E. and Holland, D. M. (2012). Space-time fusion under error in computer model output: an application to modeling air quality. Biometrics 68, 837-848; 2) Berrocal, V., Gelfand, A. E. and Holland, D. M. (2010). A bivariate space-time downscaler under space and time misalignment. The Annals of Applied Statistics 4, 1942-1975; and 3) Berrocal, V., Gelfand, A. E., and Holland, D. M. (2010). A spatio-temporal downscaler for output from numerical models. J. of Agricultural, Biological,and Environmental Statistics 15, 176-197) is used to provide daily, predictive PM2.5 (daily average) and O3 (daily 8-hr maximum) surfaces for 2012. Summer (O3) and annual (PM2.5) means calculated and published. The downscaling fusion model uses both air quality monitoring data from the National Air Monitoring Stations/State and Local Air Monitoring Stations (NAMS/SLAMS) and numerical output from the Models-3/Community Multiscale Air Quality (CMAQ). Currently, predictions at the US census tract centroid locations within the 12 km CMAQ domain are archived. Predictions at the CMAQ grid cell centroids, or any desired set of locations co

  3. COCMP Surface Current Mapping Reveals Eddy and Upwelling Jet off Cape Mendocino

    NASA Astrophysics Data System (ADS)

    Crawford, G. B.; Halle, C.; Largier, J.; Stone, S.

    2008-12-01

    Ocean surface currents are now being measured continuously over a roughly 2000 km stretch of the western US continental shelf from south of Tijuana, Mexico to the Columbia River. A long-standing gap in this coverage was finally filled on August 12, 2008, with the installation of a long-range Seasonde radar system at Shelter Cove, California (as a part of California's COCMP project). During its first three weeks of operation, this radar has revealed a large (~170 km diameter), stable, anticyclonic eddy southwest of Cape Mendocino in this poorly studied region. Upwelling-favorable winds appear to create an upwelling jet along the eastern edge of the eddy, leading to maximum daily-averaged current speeds up to 80 cm/s, and MODIS-derived chlorophyll concentrations up to 30 mg/m3 in the jet (compared to ~1 mg/m3 in the eddy center). AVHRR data reveal SST differences between the jet and the eddy center of 1.5 to 2.5 °C during these 3 weeks. These complex circulation structures modify water pathways and may interrupt nutrient delivery to locations farther south. We discuss the spatial and temporal evolution of these features.

  4. High resolution synoptic salinity mapping to identify groundwater--surface water discharges in lowland rivers.

    PubMed

    Pai, Henry; Villamizar, Sandra R; Harmon, Thomas C

    2015-04-21

    Quantifying distributed lateral groundwater contributions to surface water (GW-SW discharges) is a key aspect of tracking nonpoint-source pollution (NPSP) within a watershed. In this study, we characterized distributed GW-SW discharges and associated salt loading using elevated GW specific conductance (SC) as a tracer along a 38 km reach of the Lower Merced River in Central California. High resolution longitudinal surveys for multiple flows (1.3-150 m(3) s(-1)) revealed river SC gradients that mainly decreased with increasing flow, suggesting a dilution effect and/or reduced GW-SW discharges due to hydraulic gradient reductions. However, exceptions occurred (gradients increasing with increasing flow), pointing to complex spatiotemporal influences on GW-SW dynamics. The surveys revealed detailed variability in salinity gradients, from which we estimated distributed GW-SW discharge and salt loading using a simple mixing model. Modeled cumulative GW discharges for two surveys unaffected by ungauged SW discharges were comparable in magnitude to differential gauging-based discharge estimates and prior GW-SW studies along the same river reach. Ungauged lateral inlets and sparse GW data limited the study, and argue for enhancing monitoring efforts. Our approach provides a rapid and economical method for characterizing NPSP for gaining rivers in the context of integrated watershed modeling and management.

  5. Mapping Dust Input to the Global Ocean using Thorium Isotope Measurements in Surface Sediments

    NASA Astrophysics Data System (ADS)

    Kienast, S. S.; Winckler, G.; Lippold, J.; Mahowald, N. M.

    2012-12-01

    Dust input into the ocean-atmosphere system has significant ramifications for biogeochemical cycles and global climate. Thorium-232, sometimes referred to as primordial Thorium, is the longest lived (1.4 1010 yrs) isotope in the U-Th decay chain. It is greatly enriched in upper continental crust compared to oceanic crust and mid-ocean ridge basalt (MORB) like volcanogenic material. In remote areas of the ocean, away from hemipelagic sources of continental material, it is assumed to be of aeolian origin. In conjunction with 230Th-flux normalization, 232Th measurements are thus becoming a promising new proxy for dust accumulation in the present and past ocean. Here, we present a pilot data compilation of previously published 230Th-normalized fluxes of 232Th from a large set of surface sediments originating from the equatorial Pacific, equatorial Atlantic, Southern Ocean, and other areas, complemented by unpublished data. We compare these 232Th fluxes with estimates of present day dust accumulation derived from a coupled atmosphere, land, ocean, and sea-ice model (CCSM-SMOB1). There is excellent agreement between sedimentary and model derived dust fluxes in e.g. the equatorial Atlantic and eastern equatorial Pacific. In the western equatorial Pacific, we observe differences between the sedimentary 232Th record and model estimates. Potential reasons for these discrepancies, and implications for the use of 232Th as dust proxy will be discussed. 1Mahowald et al. . J. Geosphys.Res.111, 2006

  6. High-resolution topography along surface rupture of the 16 October 1999 Hector Mine, California (Mw 7.1) from airborne laser swath mapping

    USGS Publications Warehouse

    Hudnutt, K.W.; Borsa, A.; Glennie, C.; Minster, J.-B.

    2002-01-01

    In order to document surface rupture associated with the Hector Mine earthquake, in particular, the area of maximum slip and the deformed surface of Lavic Lake playa, we acquired high-resolution data using relatively new topographic-mapping methods. We performed a raster-laser scan of the main surface breaks along the entire rupture zone, as well as along an unruptured portion of the Bullion fault. The image of the ground surface produced by this method is highly detailed, comparable to that obtained when geologists make particularly detailed site maps for geomorphic or paleoseismic studies. In this case, however, for the first time after a surface-rupturing earthquake, the detailed mapping is along the entire fault zone rather than being confined to selected sites. These data are geodetically referenced, using the Global Positioning System, thus enabling more accurate mapping of the rupture traces. In addition, digital photographs taken along the same flight lines can be overlaid onto the precise topographic data, improving terrain visualization. We demonstrate the potential of these techniques for measuring fault-slip vectors.

  7. Surface Map Traffic Intent Displays and Net-Centric Data-link Communications for NextGen

    NASA Technical Reports Server (NTRS)

    Shelton, Kevin J.; Prinzel, Lawrence J., III; Jones, Denise R.; Allamandola, Angela S.; Arthur, Jarvis J., III; Bailey, Randall E.

    2009-01-01

    By 2025, U.S. air traffic is predicted to increase three fold and may strain the current air traffic management system, which may not be able to accommodate this growth. In response to this challenge, a revolutionary new concept has been proposed for U.S. aviation operations, termed the Next Generation Air Transportation System or "NextGen". Many key capabilities are being identified to enable NextGen, including the use of data-link communications. Because NextGen represents a radically different approach to air traffic management and requires a dramatic shift in the tasks, roles, and responsibilities for the flight deck, there are numerous research issues and challenges that must be overcome to ensure a safe, sustainable air transportation system. Flight deck display and crew-vehicle interaction concepts are being developed that proactively investigate and overcome potential technology and safety barriers that might otherwise constrain the full realization of NextGen. The paper describes simulation research, conducted at National Aeronautics and Space Administration (NASA) Langley Research Center, examining data-link communications and traffic intent data during envisioned four-dimensional trajectory (4DT)-based and equivalent visual (EV) surface operations. Overall, the results suggest that controller pilot data-link communications (CPDLC) with the use of mandatory pilot read-back of all clearances significantly enhanced situation awareness for 4DT and EV surface operations. The depiction of graphical traffic state and intent information on the surface map display further enhanced off-nominal detection and pilot qualitative reports of safety and awareness.

  8. Mapping the land surface for global atmosphere-biosphere models: Toward continuous distributions of vegetation's functional properties

    NASA Astrophysics Data System (ADS)

    Defries, Ruth S.; Field, Christopher B.; Fung, Inez; Justice, Christopher O.; Los, Sietse; Matson, Pamela A.; Matthews, Elaine; Mooney, Harold A.; Potter, Christopher S.; Prentice, Katharine; Sellers, Piers J.; Townshend, John R. G.; Tucker, Compton J.; Ustin, Susan L.; Vitousek, Peter M.

    1995-10-01

    Global land surface characteristics are important boundary conditions for global models that describe exchanges of water, energy, and carbon dioxide between the atmosphere and biosphere. Existing data sets of global land cover are based on classification schemes that characterize each grid cell as a discrete vegetation type. Consequently, parameter fields derived from these data sets are dependent on the particular scheme and the number of vegetation types it includes. The functional controls on exchanges of water, energy, and carbon dioxide between the atmosphere and biosphere are now well enough understood that it is increasingly feasible to model these exchanges using a small number of vegetation characteristics that either are related to or closely related to the functional controls. Ideally, these characteristics would be mapped as continuous distributions to capture mixtures and gradients in vegetation within the cell size of the model. While such an approach makes it more difficult to build models from detailed observations at a small number of sites, it increases the potential for capturing functionally important variation within, as well as between, vegetation types. Globally, the vegetation characteristics that appear to be most important in controlling fluxes of water, energy, and carbon dioxide include (1) growth form (tree, shrub, herb), (2) seasonality of woody vegetation (deciduous, evergreen), (3) leaf type (broadleaf, coniferous), (4) photosynthetic pathway of nonwoody vegetation (C3, C4), (5) longevity (annual, perennial), and (6) type and intensity of disturbance (e.g., cultivation, fire history). Many of these characteristics can be obtained through remote sensing, though some require ground-based information. The minimum number and the identity of the required land surface characteristics almost certainly vary with the intended objective, but the philosophy of driving models with continuous distributions of a small number of land surface

  9. Evaluation of a moderate resolution, satellite-based impervious surface map using an independent, high-resolution validation data set

    USGS Publications Warehouse

    Jones, J.W.; Jarnagin, T.

    2009-01-01

    Given the relatively high cost of mapping impervious surfaces at regional scales, substantial effort is being expended in the development of moderate-resolution, satellite-based methods for estimating impervious surface area (ISA). To rigorously assess the accuracy of these data products high quality, independently derived validation data are needed. High-resolution data were collected across a gradient of development within the Mid-Atlantic region to assess the accuracy of National Land Cover Data (NLCD) Landsat-based ISA estimates. Absolute error (satellite predicted area - "reference area") and relative error [satellite (predicted area - "reference area")/ "reference area"] were calculated for each of 240 sample regions that are each more than 15 Landsat pixels on a side. The ability to compile and examine ancillary data in a geographic information system environment provided for evaluation of both validation and NLCD data and afforded efficient exploration of observed errors. In a minority of cases, errors could be explained by temporal discontinuities between the date of satellite image capture and validation source data in rapidly changing places. In others, errors were created by vegetation cover over impervious surfaces and by other factors that bias the satellite processing algorithms. On average in the Mid-Atlantic region, the NLCD product underestimates ISA by approximately 5%. While the error range varies between 2 and 8%, this underestimation occurs regardless of development intensity. Through such analyses the errors, strengths, and weakness