Science.gov

Sample records for continuum intensity distribution

  1. On the continuum intensity distribution of the solar photosphere

    NASA Astrophysics Data System (ADS)

    Wedemeyer-Böhm, S.; Rouppe van der Voort, L.

    2009-08-01

    Context: For many years, there seemed to be significant differences between the continuum intensity distributions derived from observations and simulations of the solar photosphere. Aims: In order to settle the discussion on these apparent discrepancies, we present a detailed comparison between simulations and seeing-free observations that takes into account the crucial influence of instrumental image degradation. Methods: We use a set of images of quiet Sun granulation taken in the blue, green and red continuum bands of the Broadband Filter Imager of the Solar Optical Telescope (SOT) onboard Hinode. The images are deconvolved with point spread functions (PSF) that account for non-ideal contributions due to instrumental stray-light and imperfections. In addition, synthetic intensity images are degraded with the corresponding PSFs. The results are compared with respect to spatial power spectra, intensity histograms, and the centre-to-limb variation of the intensity contrast. Results: The intensity distribution of SOT granulation images is broadest for the blue continuum at disc-centre and narrows towards the limb and for longer wavelengths. The distributions are relatively symmetric close to the limb but exhibit a growing asymmetry towards disc-centre. The intensity contrast, which is connected to the width of the distribution, is found to be (12.8 ± 0.5)%, (8.3 ± 0.4)%, and (6.2 ± 0.2)% at disc-centre for blue, green, and red continuum, respectively. Removing the influence of the PSF unveils much broader intensity distributions with a secondary component that is otherwise only visible as an asymmetry between the darker and brighter than average part of the distribution. The contrast values increase to (26.7 ± 1.3)%, (19.4 ± 1.4)%, and (16.6 ± 0.7)% for blue, green, and red continuum, respectively. The power spectral density of the images exhibits a pronounced peak at spatial scales characteristic for the granulation pattern and a steep decrease towards

  2. The solar continuum intensity distribution. Settling the conflict between observations and simulations

    NASA Astrophysics Data System (ADS)

    Wedemeyer-Böhm, S.; Rouppe van der Voort, L.

    For many years, there seemed to be significant differences between the continuum intensity distributions derived from observations and simulations of the solar photosphere. In order to settle the discussion on these apparent discrepancies, we present a detailed comparison between simulations and seeing-free observations that takes into account the crucial influence of instrumental image degradation. We use a set of images of quiet Sun granulation taken in the blue, green and red continuum bands of the Broadband Filter Imager of the Solar Optical Telescope (SOT) onboard Hinode. The images are deconvolved with Point Spread Functions (PSF) that account for non-ideal contributions due to instrumental stray-light and imperfections. In addition, synthetic intensity images are degraded with the corresponding PSFs. The results are compared with respect to spatial power spectra, intensity histograms, and the centre-to-limb variation of the intensity contrast. The observational findings are well matched with corresponding synthetic observables from three-dimensional radiation (magneto-)hydrodynamic simulations. We conclude that the intensity contrast of the solar continuum intensity is higher than usually derived from ground-based observations and is well reproduced by modern numerical simulations. Properly accounting for image degradation effects is of crucial importance for comparisons between observations and numerical models. It finally settles the traditionally perceived conflict between observations and simulations.

  3. LOGNORMAL INTENSITY DISTRIBUTION OF THE FAR-ULTRAVIOLET CONTINUUM BACKGROUND SHORTWARD OF Ly{alpha}

    SciTech Connect

    Seon, Kwang-Il

    2013-07-20

    The diffuse far-ultraviolet (FUV) continuum radiation 'longward' of Ly{alpha} (1216 A) is well known to correlate with the dust emission at 100 {mu}m. However, it has been claimed that the FUV continuum background 'shortward' of Ly{alpha} shows very weak or no correlation with the 100 {mu}m emission. In this paper, the observational data of the diffuse FUV radiation by the Far Ultraviolet Spectroscopic Explorer (FUSE) are reexamined in order to investigate the correlation between the diffuse FUV radiation shortward of Ly{alpha} and the 100 {mu}m emission. Large fluctuations were confirmed in the linear-linear correlation plots, but good correlations were found in the log-log plots. The large fluctuations in the linear-linear plots, and thus poor correlations, between the FUV and 100 {mu}m intensities were attributed to the lognormal property of the FUV intensity distribution. The standard deviation of the intensity distribution of the FUV radiation shortward of Ly{alpha} was found to be {sigma}{sub logI} = 0.16-0.25. The result is consistent with that obtained not only for the FUV radiation longward of 1216 A but also with the dust column density measurements of various molecular clouds. This implies that most of the diffuse FUV radiation shortward of Ly{alpha} is dust-scattered light in the turbulent interstellar medium. The diffuse FUV data obtained from the Voyager missions were also investigated. However, much wider random fluctuations were found compared with the FUSE data, which is most likely due to the systematic difficulties in data reduction of the Voyager data.

  4. Precompound nucleon angular distributions in the continuum

    SciTech Connect

    Blann, M.; Scobel, W.; Plechaty, E.

    1985-08-01

    Angular distributions for nucleon induced reactions (incident energies 14 to 90 MeV) leading to precompound nucleon emission in the continuum (emitted particle energies 9-70 MeV) are calculated based on nucleon-nucleon scattering kinematics for an incident nucleon on a Fermi gas. Analytic expressions due to Kikuchi and Kawai are used for the single scattering kernel. The geometry dependent hybrid model is used to generate the differential cross sections for first, second, etc. order scattering, these weightings being used to fold the single scattering kernel. Results are found to reproduce all experimental angular distributions quite well at angles in the 20/sup 0/ to 90/sup 0/ range. Ad-hoc modifications to approximate quantal effects and Coulomb deflections are explored, but the results do not seem to offer a consistent means of reproducing back angle yields, and give generally poorer results at very forward angles.

  5. Characterizing the radio continuum emission from intense starburst galaxies

    NASA Astrophysics Data System (ADS)

    Galvin, T. J.; Seymour, N.; Filipović, M. D.; Tothill, N. F. H.; Marvil, J.; Drouart, G.; Symeonidis, M.; Huynh, M. T.

    2016-09-01

    The intrinsic thermal (free-free) and non-thermal (synchrotron) emission components that comprise the radio continuum of galaxies represent unique, dust-free measures of star formation rates (SFR). Such high SFR galaxies will dominate the deepest current and future radio surveys. We disentangle the thermal and non-thermal emission components of the radio continuum of six ultraluminous infrared galaxies (LFIR > 1012.5 L⊙) at redshifts of 0.2 ≤ z ≤ 0.5 and 22 IR selected galaxies. Radio data over a wide frequency range (0.8 < ν < 10 GHz) are fitted with a star-forming galaxy model comprising of thermal and non-thermal components. The luminosities of both radio continuum components are strongly correlated to the 60 μm luminosity across many orders of magnitude (consistent with the far-IR to radio correlation). We demonstrate that the spectral index of the radio continuum spectral energy distribution is a useful proxy for the thermal fraction. We also find that there is an increase in mean and scatter of the thermal fraction with FIR to radio luminosity ratio which could be influenced by different time-scales of the thermal and non-thermal emission mechanisms.

  6. Angular distribution and polarization of the continuum emission in anisotropic plasmas

    NASA Astrophysics Data System (ADS)

    Lamoureux, M.; Jacquet, L.; Pratt, R. H.

    1989-06-01

    This study illustrates the interest of continuum spectra resolved in angle and polarization for investigating the anisotropy of a plasma. After discussing the validity of two types of relatively simple atomic bremsstrahlung cross sections, we establish easily usable expressions for the continuum emissivity coefficients (emission due to bremsstrahlung and direct radiative recombination) appropriate for electron distributions of a plasma with toroidal symmetry. In the example of a tokamak plasma, the distribution functions for the superthermal electrons were obtained from a Monte Carlo code. The simulated and experimental spectra (measured only in one direction of observation and with no polarization resolution) are in good agreement. The theoretical evaluations show the interest of more detailed measurements. The predicted dependence of the intensity of radiation on the direction of observation and the predicted polarization are large, and they would be a good means to probe the evaluation of the electron distributions in detail and, more generally, to diagnose the anisotropy of the free electrons in plasmas.

  7. Continuum Intensity and Magnetic Field Relationship in Sunspots

    NASA Astrophysics Data System (ADS)

    Leonard, Trevor W.; Choudhary, D. P.

    2007-05-01

    The brightness (I) and magnetic field (B) distributions (I-B relationship) of sunspots are closely related. Several previous studies show that the relationship depends on the spot size, disk position, life time, and phase of the solar cycle in which it appears. The I-B relationship might also change from cycle to cycle. Many of the previous studies were conducted by single position measurements over the spot. Here, we present the results of a study of the I-B relationship using a uniform set of imaging observations of about 272 sunspots over the last two solar cycles at the San Fernando Observatory. The corresponding full disk magnetograms are from MDI-SOHO. The first result to be presented is the I-B relationship of sunspots. The second result is from an examination of the linear part of the I-B relationship, which shows that larger spots have a stiffer dependency compared to small spots. Another such dependency is more pronounced for the spots with a large umbra-penumbra ratio. Furthermore, the spots closer to the disk center have a stiffer I-B slope compared to the spots situated towards the limb. Finally, we explore the I-B properties of spots in relation to their corresponding solar hemispheres, as a function of their evolution history, dependence on their magnetic polarity, and any dependency on solar cycle. This work was partially supported by Cottrell College Science Award CC6496.

  8. The continuum intensity as a function of magnetic field. II. Local magnetic flux and convective flows

    NASA Astrophysics Data System (ADS)

    Kobel, P.; Solanki, S. K.; Borrero, J. M.

    2012-06-01

    Context. To deepen our understanding of the role of small-scale magnetic fields in active regions (ARs) and in the quiet Sun (QS) on the solar irradiance, it is fundamental to investigate the physical processes underlying their continuum brightness. Previous results showed that magnetic elements in the QS reach larger continuum intensities than in ARs at disk center, but left this difference unexplained. Aims: We use Hinode/SP disk center data to study the influence of the local amount of magnetic flux on the vigour of the convective flows and the continuum intensity contrasts. Methods: The apparent (i.e. averaged over a pixel) longitudinal field strength and line-of-sight (LOS) plasma velocity were retrieved by means of Milne-Eddington inversions (VFISV code). We analyzed a series of boxes taken over AR plages and the QS, to determine how the continuum intensity contrast of magnetic elements, the amplitude of the vertical flows and the box-averaged contrast were affected by the mean longitudinal field strength in the box (which scales with the total unsigned flux in the box). Results: Both the continuum brightness of the magnetic elements and the dispersion of the LOS velocities anti-correlate with the mean longitudinal field strength. This can be attributed to the "magnetic patches" (here defined as areas where the longitudinal field strength is above 100 G) carrying most of the flux in the boxes. There the velocity amplitude and the spatial scale of convection are reduced. Due to this hampered convective transport, these patches appear darker than their surroundings. Consequently, the average brightness of a box decreases as the the patches occupy a larger fraction of it and the amount of embedded flux thereby increases. Conclusions: Our results suggest that as the magnetic flux increases locally (e.g. from weak network to strong plage), the heating of the magnetic elements is reduced by the intermediate of a more suppressed convective energy transport within

  9. High angular resolution absolute intensity of the solar continuum from 1400 to 1790 A.

    NASA Technical Reports Server (NTRS)

    Brueckner, G. E.; Moe, O. K.

    1972-01-01

    Absolute intensities of the solar UV continuum from 1400 to 1790 A have been measured from rocket spectra taken on August 13, 1970. The spectra had an angular resolution of 2 arc sec by 1 arc min, and the pointing accuracy of the instrument was plus or minus 2 arc sec. This permits us to study the center-to-limb variation of the intensity with a spatial resolution of 2 arc sec. Four positions on the solar disk have been studied corresponding to values of cos theta = 0.12, 0.22, 0.28 and 0.72, where theta is the heliocentric position angle. The measurements give higher values for the intensity than recent photoelectric measurement, but are in good agreement with the intensities of Widing et al.

  10. The relationship between the carbon monoxide intensity and the radio continuum emission in spiral galaxies

    NASA Technical Reports Server (NTRS)

    Adler, David S.; Lo, K. Y.; Allen, Ronald J.

    1991-01-01

    The relationship between the velocity-integrated CO emission and the nonthermal radio continuum brightness in the disks of normal spiral galaxies is examined on a variety of length scales. On a global scale, the total CO intensity correlates strongly with the total radio continuum flux density for a sample of 31 galaxies. On scales of about 2 kpc or more in the disk of individual galaxies, it is found that the ratio I(CO)/T(20) remains fairly constant over the entire disk as well as from galaxy to galaxy. For the eight spirals in the sample, the disk-averaged values of I(CO)/T(20) range from 0.6-2.4, with the average over all eight galaxies being 1.3 +/- 0.6. It is concluded that what these various length scales actually trace are differences in the primary heating mechanism of the gas in the beam. The observed relationship between CO and nonthermal radio continuum emission can be explained by assuming that molecular gas in galactic disks is heated primarily by cosmic rays. The observed relationship is used to show that the brightness of synchrotron emission is proportional to n(cr) exp 0.4 - 0.9 in galactic disks.

  11. Generation of High-Order Harmonic Continuum Supporting Single Attosecond Pulse in Argon Driven by Intense 7 fs Laser Pulse

    NASA Astrophysics Data System (ADS)

    Zheng, Y. H.; Xiong, H.; Peng, Y.; Xu, H.; Yang, X.; Zeng, Z. N.; Chen, X. W.; Li, R. X.; Zeng, H. P.; Xu, Z. Z.

    High-order harmonic continuum in the cutoff is demonstrated with an argon gas cell driven by 0.4 mJ/7 fs (FWHM) ultrashort intense laser pulse. We find that the spectral structure, the modulation depth and the continuum bandwidth of the high-order harmonic spectra vary when the carrier-envelope phase (CEP) of driving laser pulse is stabilized at different values. At some CEP values, a continuous spectrum of <17% modulation depth and 10 eV continuum bandwidth is achieved, supporting a transform-limited 300 attosecond single pulse in time domain.

  12. The spatial distribution of ultraviolet line and continuum emission in Herbig-Haro objects

    NASA Technical Reports Server (NTRS)

    Lee, M. G.; Boehm, K. H.; Temple, S. D.; Raga, A. C.; Mateo, M. L.

    1988-01-01

    Archival IUE data and monochromatic CCD images in the optical range are used to compare the spatial distribution of UV and optical emission in HH 1, HH 2, HH 24, HH 32, HH 43, and HH 47. For all six objects, the observed UV radiation is shown to originate in the objects themselves. The results indicate that the C IV and semiforbidden emission-line regions are small. Although the continuum in the IUE short-wavelength range displays a distribution that is broader than that of any measured line emission in the UV or optical range, the continuum distribution in the IUE long-wavelength range is quite narrow.

  13. Distributed Storage Systems for Data Intensive Computing

    SciTech Connect

    Vazhkudai, Sudharshan S; Butt, Ali R; Ma, Xiaosong

    2012-01-01

    In this chapter, the authors present an overview of the utility of distributed storage systems in supporting modern applications that are increasingly becoming data intensive. Their coverage of distributed storage systems is based on the requirements imposed by data intensive computing and not a mere summary of storage systems. To this end, they delve into several aspects of supporting data-intensive analysis, such as data staging, offloading, checkpointing, and end-user access to terabytes of data, and illustrate the use of novel techniques and methodologies for realizing distributed storage systems therein. The data deluge from scientific experiments, observations, and simulations is affecting all of the aforementioned day-to-day operations in data-intensive computing. Modern distributed storage systems employ techniques that can help improve application performance, alleviate I/O bandwidth bottleneck, mask failures, and improve data availability. They present key guiding principles involved in the construction of such storage systems, associated tradeoffs, design, and architecture, all with an eye toward addressing challenges of data-intensive scientific applications. They highlight the concepts involved using several case studies of state-of-the-art storage systems that are currently available in the data-intensive computing landscape.

  14. Direct extraction of intense-field-induced polarization in the continuum on the attosecond time scale from transient absorption

    NASA Astrophysics Data System (ADS)

    Li, X.; Haxton, D. J.; Gaarde, M. B.; Schafer, K. J.; McCurdy, C. W.

    2016-02-01

    A procedure is suggested for using transient absorption spectroscopy above the ionization threshold to measure the polarization of the continuum induced by an intense optical pulse. In this way transient absorption measurement can be used to probe subfemtosecond intense field dynamics in atoms and molecules. The method is based on an approximation to the dependence of these spectra on time delay between an attosecond XUV probe pulse and an intense pump pulse that is tested over a wide range of intensities and time delays by all-electrons-active calculations using the multiconfiguration time-dependent Hartree-Fock method in the case of neon.

  15. Scale invariance of continuum size distribution upon irreversible growth of surface islands

    NASA Astrophysics Data System (ADS)

    Dubrovskii, V. G.; Sokolova, Zh. V.

    2015-06-01

    The continuum kinetic equation for irreversible heterogeneous growth of a surface island is ana-lyzed given a special form of the dependence of capture coefficient σ on size s and coverage of the surface Θ. It is shown that, if σ( s, Θ) = α(Θ)( a + s)β, the function α(Θ) is arbitrary, and 0 ≤ β ≤ 1, then the solutions of the continuum equation of the first order satisfy the hypothesis about the scale invariance of the size distribu-tion (scaling) in a single exceptional case—at ≤ = 1. The obtained results testify about the presence of a fun-damental relation of the scaling and linearity of the dependence σ( s). Problems about associations of distri-bution functions in continuum and discrete growth models and about application of the obtained solutions for modeling and interpretation of experimental data in different systems are discussed.

  16. Aspects of disordered eating continuum in elite high-intensity sports.

    PubMed

    Sundgot-Borgen, J; Torstveit, M K

    2010-10-01

    Dieting is an important risk factor for disordered eating and eating disorders. Disordered eating occurs on a continuum from dieting and restrictive eating, abnormal eating behavior, and finally clinical eating disorders. The prevalence of eating disorders is increased in elite athletes and for this group the cause of starting to diet is related to (a) perception of the paradigm of appearance in the specific sport, (b) perceived performance improvements, and (c) sociocultural pressures for thinness or an "ideal" body. Athletes most at risk for disordered eating are those involved in sports emphasizing a thin body size/shape, a high power-to-weight ratio, and/or sports utilizing weight categories, such as in some high-intensity sports. In addition to dieting, personality factors, pressure to lose weight, frequent weight cycling, early start of sport-specific training, overtraining, injuries, and unfortunate coaching behavior, are important risk factors. To prevent disordered eating and eating disorders, the athletes have to practice healthy eating, and the medical staff of teams and parents must be able to recognize symptoms indicating risk for eating disorders. Coaches and leaders must accept that disordered eating can be a problem in the athletic community and that openness regarding this challenge is important. PMID:20840569

  17. Spectrophotometry of Wolf-Rayet stars. I - Continuum energy distributions

    NASA Technical Reports Server (NTRS)

    Morris, Patrick W.; Brownsberger, Kenneth R.; Conti, Peter S.; Massey, Philip; Vacca, William D.

    1993-01-01

    All available low-resolution IUE spectra are assembled for Galactic, LMC, and SMC W-R stars and are merged with ground-based optical and NIR spectra in order to collate in a systematic fashion the shapes of these energy distributions over the wavelength range 0.1-1 micron. They can be consistently fitted by a power law of the form F(lambda) is approximately equal to lambda exp -alpha over the range 1500-9000 A to derive color excesses E(B-V) and spectral indices by removing the 2175-A interstellar absorption feature. The WN star color excesses derived are found to be in good agreement with those of Schmutz and Vacca (1991) and Koesterke et al. (1991). Significant heterogeneity in spectral index values was generally seen with any given subtype, but the groups consisting of the combined set of Galactic and LMC W-R stars, the separate WN and WC sequences, and the Galactic and LMC W-R stars all showed a striking and consistent Gaussian-like frequency distribution of values.

  18. IUE observations of a luminous M supergiant that exhibits intense continuum in the far ultraviolet

    NASA Technical Reports Server (NTRS)

    Michalitsianos, A. G.; Kafatos, M.; Hobbs, R. W.

    1980-01-01

    Observations of the late type M supergiant TV Gem (M1Iab) reveal strong UV continuum between 1200 A and 3200 A. The continuum is essentially featureless with the exception of a number of broad absorption features in the short wavelength spectra range. An absorption feature centered around 1400 A could be due to Si IV absorption found typically in spectra of middle B type stars. UV emission from this star is unexpected because earlier ground-based observations give no indication of a possible association with an early companion or circumstellar ionized nebulosity. A B9 or A1 III - IV type star approximately 2to 3 magnitudes fainter than the M star could explain the level of UV continuum observed, but a fully self consistent explanation that includes the B-V color index of TV Gem is not as yet possible. The continuum flux dependence with wavelength in the UV spectral range could be attributed to a high energy source such as an accretion disc. It is suggested TV Gem is a good candidate for HEAO-2 (Einstein) satellite observations because a high energy object in close proximity to the M star would likely be a source of soft X-ray emission.

  19. Center-to-limb variation of intensity and polarization in continuum spectra of FGK stars for spherical atmospheres

    NASA Astrophysics Data System (ADS)

    Kostogryz, N. M.; Milic, I.; Berdyugina, S. V.; Hauschildt, P. H.

    2016-02-01

    Aims: One of the necessary parameters needed for the interpretation of the light curves of transiting exoplanets or eclipsing binary stars (as well as interferometric measurements of a star or microlensing events) is how the intensity and polarization of light changes from the center to the limb of a star. Scattering and absorption processes in the stellar atmosphere affect both the center-to-limb variation of intensity (CLVI) and polarization (CLVP). In this paper, we present a study of the CLVI and CLVP in continuum spectra, taking into consideration the different contributions of scattering and absorption opacity for a variety of spectral type stars with spherical atmospheres. Methods: We solve the radiative transfer equation for polarized light in the presence of a continuum scattering, taking into consideration the spherical model of a stellar atmosphere. To cross-check our results, we developed two independent codes that are based on Feautrier and short characteristics methods, respectively, Results: We calculate the center-to-limb variation of intensity (CLVI) and polarization (CLVP) in continuum for the Phoenix grid of spherical stellar model atmospheres for a range of effective temperatures (4000-7000 K), gravities (log g = 1.0-5.5), and wavelengths (4000-7000 Å), which are tabulated and available at the CDS. In addition, we present several tests of our codes and compare our calculations for the solar atmosphere with published photometric and polarimetric measurements. We also show that our two codes provide similar results in all considered cases. Conclusions: For sub-giant and dwarf stars (log g = 3.0-4.5), the lower gravity and lower effective temperature of a star lead to higher limb polarization of the star. For giant and supergiant stars (log g = 1.0-2.5), the highest effective temperature yields the largest polarization. By decreasing the effective temperature of a star down to 4500-5500 K (depending on log g), the limb polarization decreases and

  20. Differential responding without differential reinforcement: Intensity difference, continuum position, and reinforcement density effects

    PubMed Central

    Raslear, Thomas G.

    1981-01-01

    The response rates of five groups of rats were observed during exposure to different intensities of a four kilohertz tone within a two-component multiple schedule of nondifferential reinforcement. Response rates were found to be higher during the multiple schedule component which contained the higher intensity tone. Larger differences in response rates between the two multiple schedule components occurred with greater intensity separations (30 versus 20 decibels). At the 30 decibel separation a low absolute magnitude produced larger response rate differences than a high absolute magnitude, while at the 20 decibel separation a high absolute magnitude produced larger response rate differences. Increases in reinforcement density were accompanied by decreases in response rate differences between high and low intensity components only when over-all response rates also increased. PMID:16812202

  1. Functional profiling and distribution of the forest soil bacterial communities along the soil mycorrhizosphere continuum.

    PubMed

    Uroz, S; Courty, P E; Pierrat, J C; Peter, M; Buée, M; Turpault, M P; Garbaye, J; Frey-Klett, P

    2013-08-01

    An ectomycorrhiza is a multitrophic association between a tree root, an ectomycorrhizal fungus, free-living fungi and the associated bacterial communities. Enzymatic activities of ectomycorrhizal root tips are therefore result of the contribution from different partners of the symbiotic organ. However, the functional potential of the fungus-associated bacterial communities remains unknown. In this study, a collection of 80 bacterial strains randomly selected and isolated from a soil-ectomycorrhiza continuum (oak-Scleroderma citrinum ectomycorrhizas, the ectomycorrhizosphere and the surrounding bulk soil) were characterized. All the bacterial isolates were identified by partial 16S rRNA gene sequences as members of the genera Burkholderia, Collimonas, Dyella, Mesorhizobium, Pseudomonas, Rhizobium and Sphingomonas. The bacterial strains were then assayed for β-xylosidase, β-glucosidase, N-acetyl-hexosaminidase, β-glucuronidase, cellobiohydrolase, phosphomonoesterase, leucine-aminopeptidase and laccase activities, chitin solubilization and auxin production. Using these bioassays, we demonstrated significant differences in the functional distribution of the bacterial communities living in the different compartments of the soil-ectomycorrhiza continuum. The surrounding bulk soil was significantly enriched in bacterial isolates capable of hydrolysing cellobiose and N-acetylglucosamine. In contrast, the ectomycorrhizosphere appeared significantly enriched in bacterial isolates capable of hydrolysing glucopyranoside and chitin. Notably, chitinase and laccase activities were found only in bacterial isolates belonging to the Collimonas and Pseudomonas genera. Overall, the results suggest that the ectomycorrhizal fungi favour specific bacterial communities with contrasting functional characteristics from the surrounding soil. PMID:23455431

  2. 14 CFR 25.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... light distribution and intensities. (a) General. The intensities prescribed in this section must be provided by new equipment with light covers and color filters in place. Intensities must be determined with... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Position light distribution and...

  3. 14 CFR 29.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Position light distribution and intensities. (a) General. The intensities prescribed in this section must be provided by new equipment with light covers and color filters in place. Intensities must be... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Position light distribution and...

  4. 14 CFR 27.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... light distribution and intensities. (a) General. the intensities prescribed in this section must be provided by new equipment with light covers and color filters in place. Intensities must be determined with... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Position light distribution and...

  5. 14 CFR 25.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... light distribution and intensities. (a) General. The intensities prescribed in this section must be provided by new equipment with light covers and color filters in place. Intensities must be determined with... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Position light distribution and...

  6. 14 CFR 27.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... light distribution and intensities. (a) General. the intensities prescribed in this section must be provided by new equipment with light covers and color filters in place. Intensities must be determined with... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Position light distribution and...

  7. Hydrogen transport in solids with traps in the case of continuum distribution of detrapping energies

    NASA Astrophysics Data System (ADS)

    Krasheninnikov, S. I.; Marenkov, E. D.; Smirnov, R. D.; Pisarev, A. A.

    2014-04-01

    Tritium retention in the first wall material is one of the key issues in the performance of future fusion reactors. Transport of hydrogenic species in these materials is most commonly treated as diffusion affected by trapping/detrapping processes. Usually only several trap types differing in their activation energies of hydrogen release are considered (up to three types in the TMAP7 code). We suggest that in some cases (e.g. highly damaged or disordered media) the hydrogen trapping/detrapping process is better characterized by a continuum distribution of traps over their detrapping energies. Within a random walk model we show that this assumption leads to qualitative changes in hydrogen transport in solids. Using this model we explain experimental findings on temporal dependence of deuterium outgassing from tokamaks, first wall.

  8. 14 CFR 23.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Equipment Lights § 23.1389 Position light distribution and intensities. (a) General. The intensities prescribed in this section must be provided by new equipment with each light cover and color filter in place... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Position light distribution and...

  9. 14 CFR 23.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Equipment Lights § 23.1389 Position light distribution and intensities. (a) General. The intensities prescribed in this section must be provided by new equipment with each light cover and color filter in place... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Position light distribution and...

  10. Disparities in the Population Distribution of African American and Non-Hispanic White Smokers along the Quitting Continuum

    ERIC Educational Resources Information Center

    Trinidad, Dennis R.; Xie, Bin; Fagan, Pebbles; Pulvers, Kim; Romero, Devan R.; Blanco, Lyzette; Sakuma, Kari-Lyn K.

    2015-01-01

    Purpose: To examine disparities and changes over time in the population-level distribution of smokers along a cigarette quitting continuum among African American smokers compared with non-Hispanic Whites. Methods: Secondary data analyses of the 1999, 2002, 2005, and 2008 California Tobacco Surveys (CTS). The CTS are large, random-digit-dialed,…

  11. Quantum beat oscillations in the two-color-photoionization continuum of neon and their dependence on the intensity of the ionizing laser pulse

    SciTech Connect

    Geiseler, Henning; Rottke, Horst; Steinmeyer, Guenter; Sandner, Wolfgang

    2011-09-15

    We investigate quantum beat oscillations in the photoionization continuum of Ne atoms that are photoionized by absorption of two photons via a group of excited bound states using ultrashort extreme ultraviolet and infrared laser pulses. The extreme ultraviolet pulse starts an excited-state wave packet that is photoionized by a high-intensity infrared pulse after a variable time delay. We analyze the continuum quantum beats from this two-step photoionization process and their dependence on the photoelectron kinetic energy. We find a pronounced dependence of the quantum beat amplitudes on the photoelectron kinetic energy. The dependence changes significantly with the applied infrared laser-pulse intensity. The experimental results are in good qualitative agreement with a model calculation that is adapted to the experimental situation. It accounts for the intensity dependence of the quantum beat structure through the coupling of the excited-state wave packet to other bound Ne states induced by the high-intensity infrared laser pulse.

  12. Numerical evaluation of the intensity transport equation for well-known wavefronts and intensity distributions

    NASA Astrophysics Data System (ADS)

    Campos-García, Manuel; Granados-Agustín, Fermín.; Cornejo-Rodríguez, Alejandro; Estrada-Molina, Amilcar; Avendaño-Alejo, Maximino; Moreno-Oliva, Víctor Iván.

    2013-11-01

    In order to obtain a clearer interpretation of the Intensity Transport Equation (ITE), in this work, we propose an algorithm to solve it for some particular wavefronts and its corresponding intensity distributions. By simulating intensity distributions in some planes, the ITE is turns into a Poisson equation with Neumann boundary conditions. The Poisson equation is solved by means of the iterative algorithm SOR (Simultaneous Over-Relaxation).

  13. Planck Early Results. XV. Spectral Energy Distributions and Radio Continuum Spectra of Northern Extragalactic Radio Sources

    NASA Technical Reports Server (NTRS)

    Aatrokoski, J.; Ade, P. A. R.; Aghanim, N.; Aller, H. D.; Aller, M. F.; Angelakis, E.; Amaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Balbi, A.; Banday, A. J.; Barreiro, R. B.; Bartlett, J. G.; Battaner, E.; Benabed, K.; Benoit, A.; Berdyugin, A.; Bernard, J. P.; Bersanelli, M.; Bhatia, R.; Bonaldi, A.; Bonavera, L.; Gehrels, N.

    2011-01-01

    Spectral energy distributions (SEDs) and radio continuum spectra are presented for a northern sample of 104 extragalactic radio sources. based on the Planck Early Release Compact Source Catalogue (ERCSC) and simultaneous multi frequency data. The nine Planck frequencies, from 30 to 857 GHz, are complemented by a set of simultaneous observations ranging from radio to gamma-rays. This is the first extensive frequency coverage in the radio and millimetre domains for an essentially complete sample of extragalactic radio sources, and it shows how the individual shocks, each in their own phase of development, shape the radio spectra as they move in the relativistic jet. The SEDs presented in this paper were fitted with second and third degree polynomials to estimate the frequencies of the synchrotron and inverse Compton (IC) peaks, and the spectral indices of low and high frequency radio data, including the Planck ERCSC data, were calculated. SED modelling methods are discussed, with an emphasis on proper. physical modelling of the synchrotron bump using multiple components. Planck ERCSC data also suggest that the original accelerated electron energy spectrum could be much harder than commonly thought, with power-law index around 1.5 instead of the canonical 2.5. The implications of this are discussed for the acceleration mechanisms effective in blazar shock. Furthermore in many cases the Planck data indicate that gamma-ray emission must originate in the same shocks that produce the radio emission.

  14. Intensity Distribution of the Solar Transition Region

    NASA Technical Reports Server (NTRS)

    Fisher, George H.

    1999-01-01

    The objective of this research project was to use high resolution spectroscopic observations from the SUMER instrument on SOHO to study the structure of the solar transition region. Our focus in this grant was to study the structure of the transition region in a small active region, and compare it to similar observations we made of the quiet Sun. We also used SXT and EIT data to constrain the coronal and transition region emission measure distribution.

  15. The continuum intensity as a function of magnetic field. I. Active region and quiet Sun magnetic elements

    NASA Astrophysics Data System (ADS)

    Kobel, P.; Solanki, S. K.; Borrero, J. M.

    2011-07-01

    Context. Small-scale magnetic fields are major contributors to the solar irradiance variations. Hence, the continuum intensity contrast of magnetic elements in the quiet Sun (QS) network and in active region (AR) plage is an essential quantity that needs to be measured reliably. Aims: By using Hinode/SP disk center data at a constant, high spatial resolution, we aim at updating results of earlier ground-based studies of contrast vs. magnetogram signal, and to look for systematic differences between AR plages and QS network. Methods: The field strength, filling factor and inclination of the field was retrieved by means of a Milne-Eddington inversion (VFISV code). As in earlier studies, we then performed a pixel-by-pixel study of 630.2 nm continuum contrast vs. apparent (i.e. averaged over a pixel) longitudinal magnetic field over large fields of view in ARs and in the QS. Results: The continuum contrast of magnetic elements reaches larger values in the QS (on average 3.7%) than in ARs (on average 1.3%). This could not be attributed to any systematic difference in the chosen contrast references, so that it mainly reflects an intrinsic brightness difference. The larger contrasts in the QS are in agreement with earlier, lower resolution results, although our values are larger due to our better spatial resolution. At Hinode's spatial resolution, moreover, the relationship between contrast and apparent longitudinal field strength exhibits a peak at around 700 G in both the QS and ARs, whereas earlier lower resolution studies only found a peak in the QS and a monotonic decrease in ARs. We attribute this discrepancy both to our careful removal of the pores and their close surroundings affected by the telescope diffraction, as well as to the enhanced spatial resolution and very low scattered light of the Hinode Solar Optical Telescope. We verified that the magnetic elements producing the peak in the contrast curve are rather vertical in the AR and in the QS, so that the

  16. Diffuse gamma radiation. [intensity, energy spectrum and spatial distribution from SAS 2 observations

    NASA Technical Reports Server (NTRS)

    Fichtel, C. E.; Simpson, G. A.; Thompson, D. J.

    1978-01-01

    Results are reported for an investigation of the intensity, energy spectrum, and spatial distribution of the diffuse gamma radiation detected by SAS 2 away from the galactic plane in the energy range above 35 MeV. The gamma-ray data are compared with relevant data obtained at other wavelengths, including 21-cm emission, radio continuum radiation, and the limited UV and radio information on local molecular hydrogen. It is found that there are two quite distinct components to the diffuse radiation, one of which shows a good correlation with the galactic matter distribution and continuum radiation, while the other has a much steeper energy spectrum and appears to be isotropic at least on a coarse scale. The galactic component is interpreted in terms of its implications for both local and more distant regions of the Galaxy. The apparently isotropic radiation is discussed partly with regard to the constraints placed on possible models by the steep energy spectrum, the observed intensity, and an upper limit on the anisotropy.

  17. Distribution characteristics of the intensity and extreme intensity of tropical cyclones influencing China

    NASA Astrophysics Data System (ADS)

    Zheng, Yongguang; Chen, Jiong; Tao, Zuyu

    2014-06-01

    To address the deficiency of climatological research on tropical cyclones (TCs) influencing China, we analyze the distributions of TCs with different intensities in the region, based on the best-track TC data for 1949-2011 provided by the Shanghai Typhoon Institute. We also present the distributions of 50- and 100-yr return-period TCs with different intensities using the Gumbel probability distribution. The results show that TCs with different intensities exert distinctive effects on various regions of China and its surrounding waters. The extreme intensity distributions of TCs over these different regions also differ. Super and severe typhoons mainly influence Taiwan Island and coastal areas of Fujian and Zhejiang provinces, while typhoons and TCs with lower intensities influence South China most frequently. The probable maximum TC intensity (PMTI) with 50- and 100-yr return periods influencing Taiwan Island is below 890 hPa; the PMTI with a 50-yr return period influencing the coastal areas of Fujian and Zhejiang provinces is less than 910 hPa, and that with a 100-yr return period is less than 900 hPa; the PMTI with a 50-yr return period influencing the coastal areas of Hainan, Guangdong, and the northern part of the South China Sea is lower than 930 hPa, and that with a 100-yr return period is less than 920 hPa. The results provide a useful reference for the estimation of extreme TC intensities over different regions of China.

  18. Predicting the distribution of intensive poultry farming in Thailand

    PubMed Central

    Van Boeckel, Thomas P; Thanapongtharm, Weerapong; Robinson, Timothy; D’Aietti, Laura; Gilbert, Marius

    2012-01-01

    Intensification of animal production can be an important factor in the emergence of infectious diseases because changes in production structure influence disease transmission patterns. In 2004 and 2005, Thailand was subject to two highly pathogenic avian influenza epidemic waves and large surveys were conducted of the poultry sector, providing detailed spatial data on various poultry types. This study analysed these data with the aim of establishing the distributions of extensive and intensive poultry farms, based on the number of birds per holder. Once poultry data were disaggregated into these two production systems, they were analysed in relation to anthropogenic factors using simultaneous autoregressive models. Intensive chicken production was clustered around the capital city of Bangkok and close to the main consumption and export centres. Intensively-raised ducks, mainly free-grazing, showed a distinct pattern with the highest densities distributed in a large area located in the floodplain of the Chao Phraya River. Accessibility to Bangkok, the percentage of irrigated areas and human population density were the most important predictors explaining the geographical distribution of intensively-raised poultry. The distribution of extensive poultry showed a higher predictability. Extensive poultry farms were distributed more homogeneously across the country and their distribution was best predicted by human population density. PMID:22323841

  19. Vibrational intensity distributions in the photoelectron spectrum of hydrogen

    NASA Technical Reports Server (NTRS)

    Gardner, J. L.; Samson, J. A. R.

    1975-01-01

    The intensity distribution over the H2(+) vibrational levels up to a quantum number of 15 was measured for H2 photoelectron spectra at a photon wavelength of 584 A. The data show reasonable agreement with recent calculations only in the quantum number of 0 through 8. The higher levels are populated significantly lower than predicted by theory.

  20. Rapid intensification and the bimodal distribution of tropical cyclone intensity.

    PubMed

    Lee, Chia-Ying; Tippett, Michael K; Sobel, Adam H; Camargo, Suzana J

    2016-01-01

    The severity of a tropical cyclone (TC) is often summarized by its lifetime maximum intensity (LMI), and the climatological LMI distribution is a fundamental feature of the climate system. The distinctive bimodality of the LMI distribution means that major storms (LMI >96 kt) are not very rare compared with less intense storms. Rapid intensification (RI) is the dramatic strengthening of a TC in a short time, and is notoriously difficult to forecast or simulate. Here we show that the bimodality of the LMI distribution reflects two types of storms: those that undergo RI during their lifetime (RI storms) and those that do not (non-RI storms). The vast majority (79%) of major storms are RI storms. Few non-RI storms (6%) become major storms. While the importance of RI has been recognized in weather forecasting, our results demonstrate that RI also plays a crucial role in the TC climatology. PMID:26838056

  1. Rapid intensification and the bimodal distribution of tropical cyclone intensity

    PubMed Central

    Lee, Chia-Ying; Tippett, Michael K.; Sobel, Adam H.; Camargo, Suzana J.

    2016-01-01

    The severity of a tropical cyclone (TC) is often summarized by its lifetime maximum intensity (LMI), and the climatological LMI distribution is a fundamental feature of the climate system. The distinctive bimodality of the LMI distribution means that major storms (LMI >96 kt) are not very rare compared with less intense storms. Rapid intensification (RI) is the dramatic strengthening of a TC in a short time, and is notoriously difficult to forecast or simulate. Here we show that the bimodality of the LMI distribution reflects two types of storms: those that undergo RI during their lifetime (RI storms) and those that do not (non-RI storms). The vast majority (79%) of major storms are RI storms. Few non-RI storms (6%) become major storms. While the importance of RI has been recognized in weather forecasting, our results demonstrate that RI also plays a crucial role in the TC climatology. PMID:26838056

  2. Rapid intensification and the bimodal distribution of tropical cyclone intensity

    NASA Astrophysics Data System (ADS)

    Lee, Chia-Ying; Tippett, Michael K.; Sobel, Adam H.; Camargo, Suzana J.

    2016-02-01

    The severity of a tropical cyclone (TC) is often summarized by its lifetime maximum intensity (LMI), and the climatological LMI distribution is a fundamental feature of the climate system. The distinctive bimodality of the LMI distribution means that major storms (LMI >96 kt) are not very rare compared with less intense storms. Rapid intensification (RI) is the dramatic strengthening of a TC in a short time, and is notoriously difficult to forecast or simulate. Here we show that the bimodality of the LMI distribution reflects two types of storms: those that undergo RI during their lifetime (RI storms) and those that do not (non-RI storms). The vast majority (79%) of major storms are RI storms. Few non-RI storms (6%) become major storms. While the importance of RI has been recognized in weather forecasting, our results demonstrate that RI also plays a crucial role in the TC climatology.

  3. Derivation of the Star Formation Intensity Distribution from Empirical Laws

    NASA Astrophysics Data System (ADS)

    Thompson, R. I.

    2002-12-01

    The star formation intensity distribution function, first presented by Lanzetta and his colleagues, has received significant attention both as a constraint on models of galaxy formation and as a correction for star formation missed by surface brightness dimming at high redshift. This talk demonstrates that the distribution at a redshift of 1, where it is well measured, can be matched with well known empirical laws. In particular the Schmidt law with a roll off of star formation at a critical density, a Schechter distribution of galaxy masses, and the assumption that star formation occurs in exponential disks suffices to derive the distribution with reasonable values for the adjustable parameters. Using values of the parameters at high z that are consistent with the hierarchical models of galaxy formation shows the possible evolution of the distribution with redshift.

  4. Empirical model for variation of the continuum emission in the upper atmosphere. 2. Infrared components

    NASA Astrophysics Data System (ADS)

    Semenov, A. I.; Shefov, N. N.; Medvedeva, I. V.

    2014-09-01

    The absolute integral intensity of the IR components of the continuum emission is calculated from the laboratory velocities of photochemical reactions between NO and nonexcited and excited O3 molecules. The vertical intensity distribution of the continuous radiation spectrum of the upper atmosphere (continuum) in the IR area spans a range of heights of the middle atmosphere from 10 to 15 km. A comparison of the calculated values of the continuum intensity with the results of its spectrophotometric surface measurements in the near-IR spectrum allowed refinement of the coefficient of velocity of the NO-ozone reaction responsible for origination of the continuum emission in the IR spectrum range.

  5. A comparison of the radial distribution of molecular gas and non-thermal radio continuum in spiral disks

    NASA Technical Reports Server (NTRS)

    Devereux, Nicholas A.; Young, J. S.

    1990-01-01

    The present study includes 65 spiral galaxies selected from the Five College Radio Astronomy Observatory (FCRAO) Extragalactic CO Survey for which the major axis distributions of CO emission and 1.49 GHz radio continuum emission are well determined. The radial distribution of the CO emission has been measured with the FCRAO at positions along the major axis that are spaced by one half power beam width (HPBW) (45 seconds). The radial profile of the 1.49 GHz radio continuum emission was constructed by determining the radio emission at the location of the CO measurements from the 1.49 GHz maps of Condon (1987). Large, greater than a factor of ten, radially decreasing gradients in the star formation efficiency are observed for a small percentage, approx. 10 percent, of the spirals in this sample. The majority of spirals, however, are associated with small gradients in the star formation efficiency that do not systematically increase or decrease with radius. That the star formation efficiency does not systematically decrease with radius tends to argue against a global dynamical mechanism, such as a spiral density wave, for being the dominant mechanism triggering disk star formation for the majority of spirals in this sample. The results tend to support the view that the star formation in spiral disks is dominated by a local process that depends more on the molecular cloud properties than the dynamical structure of a galaxy.

  6. Centralized vs. Distributed PACS for Intensive Care Units

    NASA Astrophysics Data System (ADS)

    Cho, Paul S.; Huang, H. K.; Tillisch, Jan

    1989-05-01

    One clinical environment which can immediately benefit from the implementation of a radiologic PACS is the intensive care unit (ICU). Our previous study has demonstrated the feasibility and timeliness of routine image transmission to an ICU. In anticipation of future expansion of this service, we have investigated two different models for a hospital-wide ICU PACS. These models included a centralized and a distributed processing PACS configuration. Their comparison indicated that although the distributed model offers some major advantages over the centralized model, the latter may hold a rightful place in the inter-departmental service, especially if the cost issue is a critical factor.

  7. Near field light intensity distribution analysis in bimodal polymer waveguide

    NASA Astrophysics Data System (ADS)

    Herzog, T.; Gut, K.

    2015-12-01

    The paper presents analysis of light intensity distribution and sensitivity in differential interferometer based on bimodal polymer waveguide. Key part is analysis of optimal waveguide layer thickness in structure SiO2/SU-8/H2O for maximum bulk refractive index sensitivity. The paper presents new approach to detecting phase difference between modes through registrations only part of energy propagating in the waveguide. Additionally in this paper the analysis of changes in light distribution when energy in modes is not equal were performed.

  8. Bayesian localization microscopy based on intensity distribution of fluorophores.

    PubMed

    Xu, Fan; Zhang, Mingshu; Liu, Zhiyong; Xu, Pingyong; Zhang, Fa

    2015-03-01

    Super-resolution microscopy techniques have overcome the limit of optical diffraction. Recently, the Bayesian analysis of Bleaching and Blinking data (3B) method has emerged as an important tool to obtain super-resolution fluorescence images. 3B uses the change in information caused by adding or removing fluorophores in the cell to fit the data. When adding a new fluorophore, 3B selects a random initial position, optimizes this position and then determines its reliability. However, the fluorophores are not evenly distributed in the entire image region, and the fluorescence intensity at a given position positively correlates with the probability of observing a fluorophore at this position. In this paper, we present a Bayesian analysis of Bleaching and Blinking microscopy method based on fluorescence intensity distribution (FID3B). We utilize the intensity distribution to select more reliable positions as the initial positions of fluorophores. This approach can improve the reconstruction results and significantly reduce the computational time. We validate the performance of our method using both simulated data and experimental data from cellular structures. The results confirm the effectiveness of our method. PMID:25672498

  9. Improved Empirical Models of Plasmaspheric Hiss Intensity and Spectral Distribution

    NASA Astrophysics Data System (ADS)

    Spasojevic, M.; Shprits, Y.; Orlova, K.

    2015-12-01

    Plasmaspheric hiss is a whistler mode emission that permeates the Earth's plasmasphere and is a significant driver of energetic electron losses through cyclotron-resonant pitch angle scattering. The EMFISIS instrument on the Van Allen Probes mission provides vastly improved measurements of the hiss wave environment including continuous measurements of the wave magnetic field cross-spectral matrix and enhanced low frequency coverage. Here, we develop empirical models of hiss wave intensity and spectral distribution using two years of Van Allen Probes data. First, we describe the construction of the hiss database. Then, we compare the hiss spectral distribution and integrated wave amplitude obtained from Van Allen Probes to those previous extracted from the CRRES mission. We present new models of the hiss frequency distribution that extend to lower frequency than conventional models of hiss. Next, we develop a multiple regression model of the average hiss magnetic field intensity as a function of Kp, L, magnetic latitude and magnetic local time. We use the full regression model to explore general trends in the data and use insights from the model to develop a simplified model of wave intensity for straightforward inclusion in quasi-linear diffusion calculations of electron scattering rates.

  10. Statistical Continuum Theory for the Effective Conductivity of Fiber Filled Polymer Composites: Effect of Orientation Distribution and Aspect Ratio

    SciTech Connect

    Mikdam, Amed; Makradi, A.; Ahzi, Said; Garmestani, Hamid; Li, Dongsheng; Remond, Y.

    2010-03-01

    Effective conductivity of polymer composites, filled with conducting fibers such as carbon nanotubes, is studied using statistical continuum theory. The fiber orientation distribution in the matrix plays a very important role on their effective properties. To take into account their orientation, shape and distribution, two-point and three-point probability distribution functions are used. The effect of fibers orientation is illustrated by comparing the effective conductivity of microstructures with oriented and non-oriented fibers. The randomly oriented fibers result in an isotropic effective conductivity. The increased fiber orientation distribution can lead to higher anisotropy in conductivity. The effect of fiber’s aspect ratio on the effective conductivity is studied by comparing microstructures with varying degrees of fiber orientation distribution. Results show that the increase in anisotropy leads to higher conductivity in the maximum fiber orientation distribution direction and lower conductivity in the transverse direction. These results are in agreement with various models from the literature that show the increase of the aspect ratio of fibers improves the electrical and thermal conductivity.

  11. Photometer for measuring intensity and rhodopsin distributions in intact eyes

    NASA Astrophysics Data System (ADS)

    Williams, Theodore P.; Webbers, Jacob P. P.

    1995-09-01

    We describe a photometer that measures light transmitted through excised eyes. The instrument, an ocular transmission photometer, employs sensitive single photon-counting techniques, and its usefulness has been tested by the study of the absorbance of rhodopsin in retinal rod cells in situ. We find that absorbances of rat rods agree well with those predicted by microspectrophotometry without making corrections for cellular mosaics. Additional tests of the ocular transmission photometer show that (a) the instrument is sensitive to subtle differences in rhodopsin absorbance, known to exist in specific locations in the rat retina, and (b) using the rate of rhodopsin bleaching as the measure of intensity, we can determine the intensity distribution at several locations across the rat retina.

  12. Subarcsecond observations of NGC 7538 IRS 1: Continuum distribution and dynamics of molecular gas

    SciTech Connect

    Zhu, Lei; Shi, Hui; Zhao, Jun-Hui; Wright, M. C. H.; Sandell, Göran; Wu, Yue-Fang; Brogan, Crystal; Corder, Stuartt

    2013-12-10

    We report new results based on the analysis of the Submillimeter Array (SMA) and Combined Array for Research in Millimeter-wave Astronomy (CARMA) observations of NGC 7538 IRS 1 at 1.3 and 3.4 mm with subarcsecond resolutions. With angular resolutions ∼0.''7, the SMA and CARMA observations show that the continuum emission at 1.3 and 3.4 mm from the hyper-compact H II region IRS 1 is dominated by a compact source with a tail-like extended structure to the southwest of IRS 1. With a CARMA B-array image at 1.3 mm convolved to 0.''1, we resolve the hyper-compact H II region into two components: an unresolved hyper-compact core, and a north-south extension with linear sizes of <270 AU and ∼2000 AU, respectively. The fine structure observed with CARMA is in good agreement with the previous Very Large Array results at centimeter wavelengths, suggesting that the hyper-compact H II region at the center of IRS 1 is associated with an ionized bipolar outflow. We image the molecular lines OCS(19-18) and CH{sub 3}CN(12-11) as well as {sup 13}CO(2-1) surrounding IRS 1, showing a velocity gradient along the southwest-northeast direction. The spectral line profiles in {sup 13}CO(2-1), CO(2-1), and HCN(1-0) observed toward IRS 1 show broad redshifted absorption, providing evidence for gas infall with rates in the range of 3-10 × 10{sup –3} M {sub ☉} yr{sup –1} inferred from our observations.

  13. Proposal for direct measurement of intense-field induced polarization in the continuum on the attosecond time scale using transient absorption

    NASA Astrophysics Data System (ADS)

    McCurdy, C. William; Haxton, Daniel; Li, Xuan

    2015-05-01

    A procedure is proposed for using transient absorption spectroscopy above the ionization threshold to measure the polarization of the continuum induced by an intense optical pulse. In this way transient absorption measurement can be used to probe sub-femtosecond intense field dynamics in atoms and molecules and extract the high frequency polarization that plays a central role in high harmonic generation. The method is based on a robust approximation to the dependence of these spectra on time-delay between an attosecond XUV probe pulse and an intense pump pulse that is verified over a wide range of intensities and time delays by all-electrons-active calculations using the Multiconfiguration Time-Dependent Hartree Fock method. To demonstrate the extraction of the field-induced polarization, we study the transient absorption spectrum of atomic Neon. Work at LBNL supported by USDOE, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division, and work at UC Davis supported by USDOE grant No. DESC0007182.

  14. UV intensity distributions of the quiet Sun observed with Sunrise

    NASA Astrophysics Data System (ADS)

    Hirzberger, Johann; Feller, A.; Riethmueller, T.; Borrero, J. M.; Schüssler, M.; Barthol, P.; Berkefeld, T.; Gandorfer, A.; Knoelker, M.; Martínez Pillet, V.; Schmidt, W.; Solanki, S.; Title, A.

    High resolution solar images in the near UV have been obtained with the Solar UV Filtergraph (SUFI) onboard the Sunrise balloon borne observatory, amongst others in wavelength regions not accessible from the ground. We present intensity distributions of the quiet Sun at different heliocentric angles, from disk center to the solar limb. These results, obtained in spectral windows at 214 nm, 313 nm (OH band), 388 nm (CN band) and 396.7 nm (CaIIH), represent an important validation of numerical models of the solar photosphere and are, thus, fundamental ingredients for our understanding of the thermal processes in the solar surface region.

  15. Stochastic equations for continuum and determination of hydraulic drag coefficients for smooth flat plate and smooth round tube with taking into account intensity and scale of turbulent flow

    NASA Astrophysics Data System (ADS)

    Dmitrenko, Artur V.

    2016-07-01

    The stochastic equations of continuum are used for determining the hydraulic drag coefficients. As a result, the formulas for the hydraulic drag coefficients dependent on the turbulence intensity and scale instead of only on the Reynolds number are proposed for the classic flows of an incompressible fluid along a smooth flat plate and a round smooth tube. It is shown that the new expressions for the classical drag coefficients, which depend only on the Reynolds number, should be obtained from these new general formulas if to use the well-known experimental data for the initial turbulence. It is found that the limitations of classical empirical and semiempirical formulas for the hydraulic drag coefficients and their deviation from the experimental data depend on different parameters of initial fluctuations in the flow for different experiments in a wide range of Reynolds numbers. On the basis of these new dependencies, it is possible to explain that the differences between the experimental results for the fixed Reynolds number are caused by the difference in the values of flow fluctuations for each experiment instead of only due to the systematic error in the processing of experiments. Accordingly, the obtained general dependencies for the smooth flat plate and the smooth round tube can serve as the basis for clarifying the results of experiments and the experimental formulas, which used for continuum flows in different devices.

  16. A Novel Microsensor for Measuring Angular Distribution of Radiative Intensity.

    PubMed

    Murphy, Thomas E; Pilorz, Stuart; Prufert-Bebout, Leslie; Bebout, Brad

    2015-01-01

    This article presents the design, construction and characterization of a novel type of light probe for measuring the angular radiance distribution of light fields. The differential acceptance angle (DAA) probe can resolve the directionality of a light field in environments with steep light gradients, such as microbial mats, without the need to remove, reorient, and reinsert the probe, a clear advantage over prior techniques. The probe consists of an inner irradiance sensor inside a concentric, moveable light-absorbing sheath. The radiative intensity in a specific zenith direction can be calculated by comparing the irradiance onto the sensor at different acceptance angles. We used this probe to measure the angular radiance distribution of two sample light fields, and observed good agreement with a conventional radiance probe. The DAA probe will aid researchers in understanding light transfer physics in dense microbial communities and expedite validation of numerical radiative transfer models for these environments. PMID:25763775

  17. Continuum radiation at Uranus

    SciTech Connect

    Kurth, W.S.; Gurnett, D.A. ); Desch, M.D. )

    1990-02-01

    Uranus has proven to be a radio source of remarkable complexity with as many as six distinctly different types of emission. One Uranian radio emission which has thus far escaped attention is an analog of continuum radiation at Earth, Jupiter, and Saturn. The emission is found to be propagating in the ordinary mode in the range of one to a few kHz on the inbound leg of the Voyager 2 encounter, shortly after the magnetopause crossing. The continuum radiation spectrum at Uranus also includes bands with frequencies as high as 12 kHz or greater on both the inbound and outbound legs. The Uranian continuum radiation is notably weak, making it more like that detected at Saturn than the extremely intense Jovian continuum radiation. The Uranian emission shows some evidence for narrow-band components lying in the same frequency regime as the continuum, completing the analogy with the other planets, which also show narrow-band components superimposed on the continuum spectrum. The authors argue that the low intensity of the Uranian continuum is most likely related to the lack of a density cavity within the Uranian magnetosphere that is deep relative to the solar wind plasma density.

  18. 14 CFR 23.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... intensities in the horizontal plane, minimum intensities in any vertical plane, and maximum intensities in...) Intensities in the horizontal plane. Each intensity in the horizontal plane (the plane containing the longitudinal axis of the airplane and perpendicular to the plane of symmetry of the airplane) must equal...

  19. 14 CFR 23.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... intensities in the horizontal plane, minimum intensities in any vertical plane, and maximum intensities in...) Intensities in the horizontal plane. Each intensity in the horizontal plane (the plane containing the longitudinal axis of the airplane and perpendicular to the plane of symmetry of the airplane) must equal...

  20. Memory intensive functional architecture for distributed computer control systems

    SciTech Connect

    Dimmler, D.G.

    1983-10-01

    A memory-intensive functional architectue for distributed data-acquisition, monitoring, and control systems with large numbers of nodes has been conceptually developed and applied in several large-scale and some smaller systems. This discussion concentrates on: (1) the basic architecture; (2) recent expansions of the architecture which now become feasible in view of the rapidly developing component technologies in microprocessors and functional large-scale integration circuits; and (3) implementation of some key hardware and software structures and one system implementation which is a system for performing control and data acquisition of a neutron spectrometer at the Brookhaven High Flux Beam Reactor. The spectrometer is equipped with a large-area position-sensitive neutron detector.

  1. Dependence of the continuum energy distribution of T Tauri stars on the location of the temperature minimum

    NASA Astrophysics Data System (ADS)

    Calvet, N.

    1981-12-01

    The influence of the position of the temperature minimum on the continuum flux produced by theoretical models of T Tauri stars is investigated. In particular, continuum fluxes for models with similar temperature profiles which differ in the position of the temperature minimum are calculated. Assumed temperature profiles are presented and the transfer and equilibrium equations for a 5-level plus continuum representation for the hydrogen atom is solved using the complete linearization scheme of Auer and Mihalas (1969). This calculation gives the electron density and departure coefficients for the first five levels of the hydrogen atom, which are then used to calculate non-LTE source functions for the continuum produced by these levels. The resulting continuum fluxes are shown and discussed. It is concluded that the discrepancy between theoretical models and observations in the blue and UV regions of the spectrum found in Calvet (1981) cannot be diminished by changing the location of the temperature minimum.

  2. 14 CFR 27.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... minimum intensities in the horizontal plane, minimum intensities in any vertical plane, and maximum...: (1) Intensities in the horizontal plane. Each intensity in the horizontal plane (the plane containing the longitudinal axis of the rotorcraft and perpendicular to the plane of symmetry of the...

  3. 14 CFR 25.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... minimum intensities in the horizontal plane, minimum intensities in any vertical plane, and maximum...: (1) Intensities in the horizontal plane. Each intensity in the horizontal plane (the plane containing the longitudinal axis of the airplane and perpendicular to the plane of symmetry of the airplane)...

  4. 14 CFR 25.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... intensities in overlapping beams, within dihedral angles L, R, and A, and must meet the following requirements... in overlaps may be used with main beam intensities substantially greater than the minima specified in §§ 25.1391 and 25.1393 if the overlap intensities in relation to the main beam intensities do...

  5. 14 CFR 27.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... intensities in overlapping beams, within dihedral angles L, R, and A, and must meet the following requirements... overlaps may be used with main beam intensities substantially greater than the minima specified in §§ 27.1391 and 27.1393, if the overlap intensities in relation to the main beam intensities do not...

  6. 14 CFR 29.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... maximum intensities in overlapping beams, within dihedral angles, L, R, and A, and must meet the following... overlaps may be used with the use of main beam intensities substantially greater than the minima specified in §§ 29.1391 and 29.1393 if the overlap intensities in relation to the main beam intensities do...

  7. 14 CFR 29.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... maximum intensities in overlapping beams, within dihedral angles, L, R, and A, and must meet the following... overlaps may be used with the use of main beam intensities substantially greater than the minima specified in §§ 29.1391 and 29.1393 if the overlap intensities in relation to the main beam intensities do...

  8. 14 CFR 29.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... maximum intensities in overlapping beams, within dihedral angles, L, R, and A, and must meet the following... overlaps may be used with the use of main beam intensities substantially greater than the minima specified in §§ 29.1391 and 29.1393 if the overlap intensities in relation to the main beam intensities do...

  9. 14 CFR 29.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... maximum intensities in overlapping beams, within dihedral angles, L, R, and A, and must meet the following... overlaps may be used with the use of main beam intensities substantially greater than the minima specified in §§ 29.1391 and 29.1393 if the overlap intensities in relation to the main beam intensities do...

  10. 14 CFR 27.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... intensities in overlapping beams, within dihedral angles L, R, and A, and must meet the following requirements... overlaps may be used with main beam intensities substantially greater than the minima specified in §§ 27.1391 and 27.1393, if the overlap intensities in relation to the main beam intensities do not...

  11. 14 CFR 25.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... intensities in overlapping beams, within dihedral angles L, R, and A, and must meet the following requirements... in overlaps may be used with main beam intensities substantially greater than the minima specified in §§ 25.1391 and 25.1393 if the overlap intensities in relation to the main beam intensities do...

  12. Can vesicle size distributions assess eruption intensity during volcanic activity?

    NASA Astrophysics Data System (ADS)

    LaRue, A.; Baker, D. R.; Polacci, M.; Allard, P.; Sodini, N.

    2013-10-01

    We studied three-dimensional (3-D) vesicle size distributions by X-ray microtomography in scoria collected during the relatively quiescent Phase II of the April-May 2010 eruption at Eyjafjallajökull volcano, Iceland. Our goal was to compare cumulative vesicle size distributions (VSDs) measured in these samples with those found in Stromboli volcano, Italy. Stromboli was chosen because its VSDs are well-characterized and show a correlation with eruption intensity: typical Strombolian activity produces VSDs with power-law exponents near 1, whereas larger and more energetic vulcanian-type explosions and Plinian eruptions produce VSDs with power-law exponents near 1.5. The first hypothesis to be tested was whether or not the samples studied in this work would contain VSDs similar to normal Strombolian products, display higher power-law exponents, or be described by exponential functions. Before making this comparison, we tested a second hypothesis, which was that the magma-water interactions in the Eyjafjallajökull eruption might have a significant effect on the VSDs. We performed 1 bar bubble-growth experiments in which the samples were inundated with water and compared them to similar control experiments without water inundation. No significant differences between the VSDs of the two sets of experiments were found, and the second hypothesis is not supported by the experimental evidence. The Phase II Eyjafjallajökull VSDs are described by power-law exponents of ~0.8, typical of normal Strombolian eruptions, and support the first hypothesis. The comparable VSDs and behavior of Phase II of the Eyjafjallajökull 2010 eruption to Stromboli are interpreted to be a reflection of similar conduit systems in both volcanoes that are being constantly fed by the ascent of mingled/mixed magma from depth. Such behavior implies that continued activity during Phase II of the Eyjafjallajökull eruption could be expected and would have been predicted, had our VSDs been measured in

  13. Can vesicle size distributions predict eruption intensity during volcanic activity?

    NASA Astrophysics Data System (ADS)

    LaRue, A.; Baker, D. R.; Polacci, M.; Allard, P.; Sodini, N.

    2013-06-01

    We studied three-dimensional (3-D) vesicle size distributions by X-ray microtomography in scoria collected during the relatively quiescent Phase II of the 2010 eruption at Eyjafjallajökull volcano, Iceland. Our goal was to compare the vesicle size distributions (VSDs) measured in these samples with those found in Stromboli volcano, Italy. Stromboli was chosen because its VSDs are well-characterized and show a correlation with eruption intensity: typical Strombolian activity produces VSDs with power-law exponents near 1, whereas larger and more energetic Vulcanian-type explosions and Plinian eruptions produce VSDs with power-law exponents near 1.5. The hypothesis to be tested was whether or not the samples studied in this work would contain VSDs similar to normal Strombolian products, display higher power-law exponents, or be described by exponential functions. Before making this comparison we tested the hypothesis that the phreatomagmatic nature of the Eyjafjallajökull eruption might have a significant effect on the VSDs. We performed 1 atm bubble-growth experiments in which the samples were inundated with water and compared them to similar, control, experiments without water inundation. No significant differences between the VSDs of the two sets of experiments were found, and the hypothesis is not supported by the experimental evidence; therefore, VSDs of magmatic and phreatomagmatic eruptions can be directly compared. The Phase II Eyjafjallajökull VSDs are described by power law exponents of ~ 0.8, typical of normal Strombolian eruptions. The comparable VSDs and behavior of Phase II of the Eyjafjallajökull 2010 eruption to Stromboli are interpreted to be a reflection of similar conduit systems in both volcanoes that are being constantly fed by the ascent of deep magma that mixes with resident magma at shallow depths. Such behavior implies that continued activity during Phase II of the Eyjafjallajökull eruption could be expected and would have been predicted

  14. Intensity distribution analysis of cathodoluminescence using the energy loss distribution of electrons.

    PubMed

    Fukuta, Masahiro; Inami, Wataru; Ono, Atsushi; Kawata, Yoshimasa

    2016-01-01

    We present an intensity distribution analysis of cathodoluminescence (CL) excited with a focused electron beam in a luminescent thin film. The energy loss distribution is applied to the developed analysis method in order to determine the arrangement of the dipole locations along the path of the electron traveling in the film. Propagating light emitted from each dipole is analyzed with the finite-difference time-domain (FDTD) method. CL distribution near the film surface is evaluated as a nanometric light source. It is found that a light source with 30 nm widths is generated in the film by the focused electron beam. We also discuss the accuracy of the developed analysis method by comparison with experimental results. The analysis results are brought into good agreement with the experimental results by introducing the energy loss distribution. PMID:26550930

  15. 14 CFR 23.1389 - Position light distribution and intensities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... overlapping beams, within dihedral angles L, R, and A, and must meet the following requirements: (1... with main beam intensities substantially greater than the minima specified in §§ 23.1391 and 23.1393, if the overlap intensities in relation to the main beam intensities do not adversely affect...

  16. Molecular above-threshold-ionization angular distributions with attosecond bichromatic intense XUV laser pulses

    NASA Astrophysics Data System (ADS)

    Yuan, Kai-Jun; Bandrauk, André D.

    2012-01-01

    Angular distributions of molecular above-threshold ionization (MATI) in bichromatic attosecond extreme ultraviolet (XUV) linear polarization laser pulses have been theoretically investigated. Multiphoton ionization in a prealigned molecular ion H2+ produces clear MATI spectra which show a forward-backward asymmetry in angular and momentum distributions which is critically sensitive to the carrier envelope phase (CEP) φ, the time delay Δτ between the two laser pulses, and the photoelectron kinetic energies Ee. The features of the asymmetry in MATI angular distributions are described well by multiphoton perturbative ionization models. Phase differences of continuum electron wave functions can be extracted from the CEP φ and time delay Δτ dependent ionization asymmetry ratio created by interfering multiphoton ionization pathways. At large internuclear distances MATI angular distributions exhibit more complex features due to laser-induced electron diffraction where continuum electron wavelengths are less than the internuclear distance.

  17. Truncated Thermal Equilibrium Distribution for Intense Beam Propagation

    SciTech Connect

    Ronald C. Davidson; Hong Qin; Steven M. Lund

    2003-02-26

    An intense charged-particle beam with directed kinetic energy ({lambda}{sub b}-1)m{sub b}c{sup 2} propagates in the z-direction through an applied focusing field with transverse focusing force modeled by F{sub foc} = -{lambda}{sub b}m{sub b}{omega}{sub beta}{sup 2} {perpendicular} x {perpendicular} in the smooth focusing approximation. This paper examines properties of the axisymmetric, truncated thermal equilibrium distribution F(sub)b(r,p perpendicular) = A exp (-H Perpendicular/T perpendicular (sub)b) = (H perpendicular-E(sub)b), where A, T perpendicular (sub)b, and E (sub)b are positive constants, and H perpendicular is the Hamiltonian for transverse particle motion. The equilibrium profiles for beam number density, n(sub)b(r) = * d{sup 2}pF(sub)b(r,p perpendicular), and transverse temperature, T perpendicular (sub)b(r) = * d{sup 2}p(p{sup 2} perpendicular/2 lambda (sbu)bm (sub)b)F(sub)b(r,p perpendicular), are calculated self-consistently including space-charge effects. Several properties of the equilibrium profiles are noteworthy. For example, the beam has a sharp outer edge radius r(sub)b with n(sub)b(r greater than or equal to rb) = 0, where r(sub)b depends on the value of E(sub)b/T (sub)perpendicular(sub)b. In addition, unlike the choice of a semi-Gaussian distribution, F{sup SG}(sub)b = A exp (-p{sup 2}(sub)perpendicular/2lambda(sub)bm(sub)bTperpendicular(sub)b) = (r-r(sub)b), the truncated thermal equilibrium distribution F(sub)b(r,p) depends on (r,p) only through the single-particle constant of the motion Hperpendiuclar and is therefore a true steady-state solution (*/*t = 0) of the nonlinear Vlasov-Maxwell equations.

  18. Nonlinear continuum growth model of multiscale reliefs as applied to rigorous analysis of multilayer short-wave scattering intensity. I. Gratings

    PubMed Central

    Goray, Leonid; Lubov, Maxim

    2013-01-01

    It is shown that taking into proper account certain terms in the nonlinear continuum equation of thin-film growth makes it applicable to the simulation of the surface of multilayer gratings with large boundary profile heights and/or gradient jumps. The proposed model describes smoothing and displacement of Mo/Si and Al/Zr boundaries of gratings grown on Si substrates with a blazed groove profile by magnetron sputtering and ion-beam deposition. Computer simulation of the growth of multilayer Mo/Si and Al/Zr gratings has been conducted. Absolute diffraction efficiencies of Mo/Si and Al/Zr gratings in the extreme UV range have been found within the framework of boundary integral equations applied to the calculated boundary profiles. It has been demonstrated that the integrated approach to the calculation of boundary profiles and of the intensity of short-wave scattering by multilayer gratings developed here opens up a way to perform studies comparable in accuracy to measurements with synchrotron radiation, at least for known materials and growth techniques. PMID:24046500

  19. Nonlinear continuum growth model of multiscale reliefs as applied to rigorous analysis of multilayer short-wave scattering intensity. I. Gratings.

    PubMed

    Goray, Leonid; Lubov, Maxim

    2013-08-01

    It is shown that taking into proper account certain terms in the nonlinear continuum equation of thin-film growth makes it applicable to the simulation of the surface of multilayer gratings with large boundary profile heights and/or gradient jumps. The proposed model describes smoothing and displacement of Mo/Si and Al/Zr boundaries of gratings grown on Si substrates with a blazed groove profile by magnetron sputtering and ion-beam deposition. Computer simulation of the growth of multilayer Mo/Si and Al/Zr gratings has been conducted. Absolute diffraction efficiencies of Mo/Si and Al/Zr gratings in the extreme UV range have been found within the framework of boundary integral equations applied to the calculated boundary profiles. It has been demonstrated that the integrated approach to the calculation of boundary profiles and of the intensity of short-wave scattering by multilayer gratings developed here opens up a way to perform studies comparable in accuracy to measurements with synchrotron radiation, at least for known materials and growth techniques. PMID:24046500

  20. The use of distributed temperature sensing technology for monitoring wildland fire intensity and distribution.

    NASA Astrophysics Data System (ADS)

    Ochoa, C. G.; Cram, D.; Hatch, C. E.; Tyler, S. W.

    2014-12-01

    Distributed temperature sensing (DTS) technology offers a viable alternative for accurately measuring wildland fire intensity and distribution in real time applications. We conducted an experiment to test the use of DTS as an alternative technology to monitor prescribed fire temperatures in real time and across a broad spatial scale. The custom fiber-optic cable consisted of three fiber optic lines buffered by polyamide, copper, and polyvinyl chloride, respectively, each armored in a stainless steel tube backfilled with Nitrogen gas. The 150 m long cable was deployed in three different 20 by 26 m experimental plots of short-grass rangeland in central New Mexico. Cable was arranged to maximize coverage of the experimental plots and allow cross-comparison between two main parallel straight-line sections approximately 8 m apart. A DTS system recorded fire temperatures every three seconds and integrated every one meter. A series of five thermocouples attached to a datalogger were placed at selected locations along the cable and also recorded temperature data every three seconds on each fiber. Results indicate that in general there is good agreement between thermocouple-measured and DTS-measured temperatures. A close match in temperature between DTS and thermocouples was particularly observed during the rising limb but not so much during the decline. The metal armoring of the fiber-optic cable remained hot longer than the thermocouples after the flames had passed. The relatively short-duration, high-intensity, prescribed burn fire in each plot resulted in temperatures reaching up to 450 degrees Celsius. In addition, DTS data allow for illustration of the irregular nature of flame speed and travel path across the rangeland grasses, a phenomenon that was impossible to quantify without the use of this tool. This study adds to the understanding of using DTS as a new alternative tool for better characterizing wildland fire intensity, distribution and travel patterns, and

  1. The Spatial Intensity Distribution of the UV Light in HH Objects. Revisited

    NASA Technical Reports Server (NTRS)

    Moro-Martin, A.; Noriego-Crespo, A.; Boehm, K.-H.; Raga, A. C.

    1996-01-01

    Simple kinematical bow shock models have successfylly explained many of the observed features in Herbig-Haro objects. It is shown that similar models can be applied to the spatial intensity distribution of the UV lines observed by IUE. Archival IUE spectra have been used for the HH 1, HH 2(H+A'), HH 2(G+B), HH 24A, HH 32A, HH 43(A+B+C), and HH 47A objects where the brightest UV lines (C IV (lambda)1549,Si III(lambda)1891, C III] (lambda)1909, C II] (lambda)2326, MgII (lambda)2799) were studied, as well as the UV continuum (modeled by the hydrogen two-photon contiuum). The quality of the IUE data is rather limited due to the broad point spread function and the low signal-to-noise, and therefore the models were degraded to make them comparable to the observations. The physical parameters used in the models were obtained from previous optical studies and varied accordingly to match the observations, but within the known uncertainties. The objects were modeled by a single bow shock model (i.e., HH 1, HH 24A, HH 32A, and HH 47A) or the superposition of two (i.e., HH 2(H+A') and HH 2(G+B) or more (i.e., HH 43(A+B+C)) of them. The idea was to take into account the complexity of the morphology of these objects, and the contribution to the UV light from diffrent condensations within the IUE aperature.

  2. Interferometric coherence measurement and radio frequency noise characterization of the 1.3 μm femtosecond intense Stokes continuum from a TZDW source

    NASA Astrophysics Data System (ADS)

    Yao, Yuhong; Knox, Wayne H.

    2015-02-01

    Photonic crystal fiber (PCF) with two closely spaced zero dispersion wavelengths (TZDW) offers a unique route to efficient energy transfer to two spectrally localized continua beyond either side of the ZDWs, which we have employed in previous work for mid-IR difference frequency generation and speckle-free red-green-blue generation. In this manuscript, we report the interferometric coherence characterization and radio frequency (RF) noise measurements of the Stokes side TZDW component. With a custom-built 1.3 W, 1035 nm, 40 MHz, 240 fs Yb:fiber chirped pulse amplifier as the pump source, we use 12 cm of commercially available TZDW PCF to excite the dual narrow-band continua from which the Stokes pulse is filtered out with a 1180 nm long wave pass filter. We achieve 0.8 to 3 nJ of narrow-band pulses within the spectral range of 1200 - 1315 nm at an average power conversion efficiency of 33%. Employing an un-balanced Michelson interferometer, measured mutual spectral coherence of the Stokes pulse is in excess of 0.76 with pump Soliton order as high as N ~70. Its measured RF noise spectrum at the first harmonic of the laser repetition rate shows less than 8 dBc/Hz increase in relative intensity noise (RIN) compared to that of the power amplifier, which is consistent with reported studies employing sub-100 fs pulses from relatively low noise oscillators. In contrast to the broadband continuum from a single ZDW PCF wherein severe de-coherence is found with pumping at high soliton order and longer pump pulse width, the reported TZDW fiber source shows preservation of intensity stability and phase coherence against variation in pump pulse parameters, which not only attests to the stability of our reported method for mid-IR generation, but also shows promising potential towards an all-fiber, efficient and low noise ultrafast source that can be helpful for applications such as biomedical deep-tissue imaging.

  3. THE 3-5 {mu}m SPECTRUM OF NGC 1068 AT HIGH ANGULAR RESOLUTION: DISTRIBUTION OF EMISSION AND ABSORPTION FEATURES ACROSS THE NUCLEAR CONTINUUM SOURCE

    SciTech Connect

    Geballe, T. R.; Mason, R. E.; Rodriguez-Ardila, A.; Axon, D. J.

    2009-08-20

    We report moderate resolution 3-5 {mu}m spectroscopy of the nucleus of NGC 1068 obtained at 0.''3 (20 pc) resolution with the spectrograph slit aligned approximately along the ionization cones of the active galactic nucleus. The deconvolved full width at half-maximum of the nuclear continuum source in this direction is 0.''3. Four coronal lines of widely different excitations were detected; the intensity of each peaks near radio knot C, approximately 0.''3 north of the infrared continuum peak, where the radio jet changes direction. Together with the broadened line profiles observed near that location, this suggests that shock ionization is the dominant excitation mechanism of the coronal lines. The depth of the 3.4 {mu}m hydrocarbon absorption is maximum at and just south of the continuum peak, similar to the 10 {mu}m silicate absorption. That and the similar and rapid variations of the optical depths of both features across the nucleus suggest that substantial portions of both arise in a dusty environment just in front of the continuum source(s). A new and tighter limit is set on the column density of CO. Although clumpy models of the dust screen might explain the shallowness of the silicate feature, the presence of the 3.4 {mu}m feature and the absence of CO are strongly reminiscent of Galactic diffuse cloud environments and a consistent explanation for them and the observed silicate feature is found if all three phenomena occur in such an environment, existing as close as 10 pc to the central engine.

  4. Software architecture for large scale, distributed, data-intensive systems

    NASA Technical Reports Server (NTRS)

    Mattmann, Chris A.; Medvidovic, Nenad; Ramirez, Paul M.

    2004-01-01

    This paper presents our experience with OODT, a novel software architectual style, and middlware-based implementation for data-intensive systems. To date, OODT has been successfully evaluated in several different science domains including Cancer Research with the National Cancer Institute (NCI), and Planetary Science with NASA's Planetary Data System (PDS).

  5. LIGHT INTENSITY AFFECTS DISTRIBUTION OF ATTACKING PSEUDACTEON CURVATUS (DIPTERA: PHORIDAE) IN A LABORATORY REARING SYSTEM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Distribution of attacking phorid flies (Pseudacteon curvatus Borgmeier) in a laboratory rearing system was tested for dependence on light intensity under 2 different light regimes. Light intensity (range, approx. 220-340 Lux) influenced fly distribution in light regime 1; in the second light regime...

  6. Continuum Nanofluidics.

    PubMed

    Hansen, Jesper S; Dyre, Jeppe C; Daivis, Peter; Todd, Billy D; Bruus, Henrik

    2015-12-15

    This paper introduces the fundamental continuum theory governing momentum transport in isotropic nanofluidic systems. The theory is an extension of the classical Navier-Stokes equation, and includes coupling between translational and rotational degrees of freedom as well as nonlocal response functions that incorporate spatial correlations. The continuum theory is compared with molecular dynamics simulation data for both relaxation processes and fluid flows, showing excellent agreement on the nanometer length scale. We also present practical tools to estimate when the extended theory should be used. It is shown that in the wall-fluid region the fluid molecules align with the wall, and in this region the isotropic model may fail and a full anisotropic description is necessary. PMID:26457405

  7. Data intensive high energy physics analysis in a distributed cloud

    NASA Astrophysics Data System (ADS)

    Charbonneau, A.; Agarwal, A.; Anderson, M.; Armstrong, P.; Fransham, K.; Gable, I.; Harris, D.; Impey, R.; Leavett-Brown, C.; Paterson, M.; Podaima, W.; Sobie, R. J.; Vliet, M.

    2012-02-01

    We show that distributed Infrastructure-as-a-Service (IaaS) compute clouds can be effectively used for the analysis of high energy physics data. We have designed a distributed cloud system that works with any application using large input data sets requiring a high throughput computing environment. The system uses IaaS-enabled science and commercial clusters in Canada and the United States. We describe the process in which a user prepares an analysis virtual machine (VM) and submits batch jobs to a central scheduler. The system boots the user-specific VM on one of the IaaS clouds, runs the jobs and returns the output to the user. The user application accesses a central database for calibration data during the execution of the application. Similarly, the data is located in a central location and streamed by the running application. The system can easily run one hundred simultaneous jobs in an efficient manner and should scale to many hundreds and possibly thousands of user jobs.

  8. Computationally intensive econometrics using a distributed matrix-programming language.

    PubMed

    Doornik, Jurgen A; Hendry, David F; Shephard, Neil

    2002-06-15

    This paper reviews the need for powerful computing facilities in econometrics, focusing on concrete problems which arise in financial economics and in macroeconomics. We argue that the profession is being held back by the lack of easy-to-use generic software which is able to exploit the availability of cheap clusters of distributed computers. Our response is to extend, in a number of directions, the well-known matrix-programming interpreted language Ox developed by the first author. We note three possible levels of extensions: (i) Ox with parallelization explicit in the Ox code; (ii) Ox with a parallelized run-time library; and (iii) Ox with a parallelized interpreter. This paper studies and implements the first case, emphasizing the need for deterministic computing in science. We give examples in the context of financial economics and time-series modelling. PMID:12804277

  9. Precipitation intensity probability distribution modelling for hydrological and construction design purposes

    NASA Astrophysics Data System (ADS)

    Koshinchanov, Georgy; Dimitrov, Dobri

    2008-11-01

    The characteristics of rainfall intensity are important for many purposes, including design of sewage and drainage systems, tuning flood warning procedures, etc. Those estimates are usually statistical estimates of the intensity of precipitation realized for certain period of time (e.g. 5, 10 min., etc) with different return period (e.g. 20, 100 years, etc). The traditional approach in evaluating the mentioned precipitation intensities is to process the pluviometer's records and fit probability distribution to samples of intensities valid for certain locations ore regions. Those estimates further become part of the state regulations to be used for various economic activities. Two problems occur using the mentioned approach: 1. Due to various factors the climate conditions are changed and the precipitation intensity estimates need regular update; 2. As far as the extremes of the probability distribution are of particular importance for the practice, the methodology of the distribution fitting needs specific attention to those parts of the distribution. The aim of this paper is to make review of the existing methodologies for processing the intensive rainfalls and to refresh some of the statistical estimates for the studied areas. The methodologies used in Bulgaria for analyzing the intensive rainfalls and produce relevant statistical estimates: The method of the maximum intensity, used in the National Institute of Meteorology and Hydrology to process and decode the pluviometer's records, followed by distribution fitting for each precipitation duration period; As the above, but with separate modeling of probability distribution for the middle and high probability quantiles. Method is similar to the first one, but with a threshold of 0,36 mm/min of intensity; Another method proposed by the Russian hydrologist G. A. Aleksiev for regionalization of estimates over some territory, improved and adapted by S. Gerasimov for Bulgaria; Next method is considering only the

  10. From Discrete 1 to 10 Towards Continuous 0 to 10: The Continuum Approach to Estimating the Distribution of Happiness in a Nation.

    PubMed

    Kalmijn, Wim

    2013-01-01

    Happiness is often measured in surveys using responses to a single question with a limited number of response options, such as 'very happy', 'fairly happy' and 'not too happy'. There is much variety in the wording and number of response options used, which limits comparability across surveys. To solve this problem, descriptive statistics of the discrete distribution in the sample are often transformed to a common discrete secondary scale, mostly ranging from 0 to 10. In an earlier publication we proposed a method for estimating statistics of the corresponding continuous distribution in the population (Kalmijn 2010). In the present paper we extend this method to questions using numerical response scales. The application of this 'continuum approach' to results obtained using the often used 1-10 numerical scale can make these comparable to those obtained on the basis of verbal response scales. PMID:23329860

  11. Numerical research of two-dimension temperature distribution in bio-tissue induced by pulse laser and continuum laser based on FEM

    NASA Astrophysics Data System (ADS)

    Shan, Ning; Zhan, Renjun; Cui, Heping

    2013-09-01

    Laser has several advantages, such as strong anti-interference ability, quick speed, high power, agility and precision. It is widely applied in military and medicine fields. When laser acts on human body, biological tissue of human body will appear the phenomenon of ablation and carbonization and solidification. In order to effectively defend excess damage by laser, the thermal effect research of skin tissue should be carried out. The heating rate and thermal damage area should be studied. In the paper, thermal energy production and thermal exchange loss used in living tissue is analyzed. The rule of thermal transfer that is irradiated by high power laser is discussed. The model of two dimensional skin tissues is built. The two dimensional transient temperature distribution generated by laser irradiation in bio-tissue is numerical simulated using finite element method. The temperature change trend generated by pulse laser and continuum laser in different radial length and axial depth bio-tissue are studied respectively. The results show that FEM method can reflect the photothermal conversion of bio-tissue exactly. Temperature is the highest in the local tissue by laser irradiated directly. The highest temperature decreases along with increasing radial length and axial depth. The highest temperature rise generated by pulse laser is more than continuum laser's. The highest temperature generated by pulse laser is not monotone increasing but is oscillation trend. The highest temperature generated by continuum laser is monotone increasing. The temperature rise mainly occurs in exodermis and derma. The temperature rise is not very significant in fat acid lining.

  12. On the theory of intensity distributions of tornadoes and other low pressure systems

    NASA Astrophysics Data System (ADS)

    Schielicke, Lisa; Névir, Peter

    Approaching from a theoretical point of view, this work presents a theory which unifies intensity distributions of different low pressure systems, based on an energy of displacement. Resulting from a generalized Boltzmann distribution, the expression of this energy of displacement is obtained by radial integration over the forces which are in balance with the pressure gradient force in the horizontal equation of motion. A scale analysis helps to find out which balance of forces prevail. According to the prevailing balances, the expression of the energy of displacement differs for various depressions. Investigating the system at the moment of maximum intensity, the energy of displacement can be interpreted as the work that has to be done to generate and finally eliminate the pressure anomaly, respectively. By choosing the appropriate balance of forces, number-intensity (energy of displacement) distributions show exponential behavior with the same decay rate β for tornadoes and cyclones, if tropical and extra-tropical cyclones are investigated together. The decay rate is related to a characteristic (universal) scale of the energy of displacement which has approximately the value Eu = β- 1 ≈ 1000 m 2s - 2 . In consequence, while the different balances of forces cause the scales of velocity, the energy of displacement scale seems to be universal for all low pressure systems. Additionally, if intensity is expressed as lifetime minimum pressure, the number-intensity (pressure) distributions should be power law distributed. Moreover, this work points out that the choice of the physical quantity which represents the intensity is important concerning the behavior of intensity distributions. Various expressions of the intensity like velocity, kinetic energy, energy of displacement and pressure are possible, but lead to different behavior of the distributions.

  13. The near wall TIRFM measurement of nano-tracer's statistical intensity distribution (SID) and determining the base intensity I0

    NASA Astrophysics Data System (ADS)

    Zheng, Xu; LNM Team

    2015-11-01

    The total internal reflection fluorescence microscopy (TIRFM) is an evanescent-wave-based technique for measuring nanoparticle dynamics very close to wall. The intensity of the evanescent wave decays exponentially (i.e. I(z) =I0exp(z/zp)) , which can provide information of the tracer particle position not just parallel but also normal to wall. However, considering the z information is encoded in tracer intensity, it is critical to determine the base intensity I0. In this study, we will first establish a model to describe the statistical intensity distribution (SID) of the nano-tracers observed in the evanescent field inspired by the works of Huang et al. A different function of particle-wall interaction and a term of the influence of the objective focal plane thickness are introduced in the present SID method. Then, TIRFM experiments are performed to measure the histogram of SID. The experimental histogram of SID is then fitted by the theoretical curve to determine I0 which is the only one fit parameter. By near wall velocity measurement, we will show that the SID method has a very high precision in determining I0 and the vertical z position of every nanotracer. Further tests show that the PDF of nano-tracers can reveal more information about how nanoparticles interact with the charged solid wall. This provides a promising method to detect the physical properties near interface.

  14. Effect of angular spread on the intensity distribution of arbitrarily shaped electron beams

    SciTech Connect

    Mohan, R.; Chui, C.S.; Fontenla, D.; Han, K.; Ballon, D.

    1988-03-01

    Knowledge of the relative intensity distribution at the patient's surface is essential for pencil beam calculations of three-dimensional dose distributions for arbitrarily shaped electron beams. To calculate the relative intensity distribution, the spatial spread resulting from angular spread is convolved with a two-dimensional step function whose shape corresponds to the applicator aperture. Two different approaches to obtain angular spread or the equivalent spatial spread are investigated. In the first method, the pencil beam angular spread is assumed to be Gaussian in shape. The angular spread constants (sigma theta) are then obtained from the slopes of measured intensity profiles. In the second method, the angular spread, in the form of an array of numerical values, is obtained by the deconvolution of measured intensity profiles. After obtaining the angular spread, the calculation for convolution is done in a number of parallel planes normal to the central axis at various distances from the electron collimator. Intensity at any arbitrary point in space is computed by interpolating between intensity distributions in adjacent planes on either side of the point. The effects of variations in angular spread as a function of field size for two treatment machines, one with a scanned electron beam and the other with a scattering foil, have been studied. The consequences of assuming angular spread to be of Gaussian shape are also examined. The electron intensity calculation techniques described in this paper apply primarily to methods of dose calculations that employ pencil beams generated using Monte Carlo simulations.

  15. ENERGY DISTRIBUTION OF TWO-ELECTRON IONIZATION OF HELIUM IN AN INTENSE LASER FIELD.

    SciTech Connect

    LAFON,R.; CHALOUPKA,J.L.; SHEEHY,B.; DIMAURO,L.F.; PAUL,P.M.; AGOSTINI,P.; KULANDER,K.C.

    2000-09-24

    It is well known that a neutral atom interacting with a strong laser field will ionize at sufficiently high intensity even for photon energies well below the ionization threshold. When the required number of photons becomes very large, this process is best described by the suppression of the Coulomb barrier by the laser's oscillating electric field, allowing the electron to tunnel into the continuum. As the laser intensity is increased, more tightly bound electrons may be successively liberated by this mechanism. Such a sequential multiple ionization, long accepted as a reasonable approach to the formidable problem of a multielectron atom interacting nonperturbatively with an intense electromagnetic field, provides fair estimates of the various charge state appearance intensities while the tunneling rates are in excellent agreement with single ionization yields. However, more accurate measurements revealed systematic and very large deviations from the tunneling rates: near appearance intensity under standard experimental conditions, the observed double ion yield is several orders of magnitude larger than predicted by the sequential rate. It soon became clear that electrons could not be considered as independent and that electron-electron correlation had to be taken into account. Dynamic correlations have been considered in several theories. First qualitatively in the shakeoff model; then empirically through the e-2e cross-section in the quantum/classical three-step model (tunnel ionization, acceleration by the oscillating electric field and e-2e recollision with the ion); recently through the so-called intense field many-body-S-matrix theory and a purely empirical model of collective tunnel ionization. The validity of these ideas has been examined using numerical models. The measurement of total ion yields over a dynamic range exceeding ten orders of magnitude, a major breakthrough made possible by the availability of high-repetition rate lasers at the beginning of

  16. Intensity Distribution of Laser Induced Plasma Generated at Different Ambient Gas Preassure

    NASA Astrophysics Data System (ADS)

    Sarmiento, Rafael; Cabanzo, Rafael; Mejia-Ospino, Enrique

    2008-04-01

    In this work, intensity distributions of laser induced plasmas have been measured by emission with two-dimensional spatial resolution and temporal resolution. The plasmas have been generated on the surfaces of steel samples at different pressures of air and argon, in the ranges from l*10-6 to 680 Torr. We compare the features of the intensity spatial and temporal distribution in the two ambient studied here. We observed that the maxima values of intensity are obtained when the pressure is maxima. The features of intensity distribution show a significant change with the ambient and gas pressure. Also, we have measured how change the size of the plasma plume with the pressure at two different ambient.

  17. Note: On the wavelength dependence of the intensity calibration factor of extreme ultraviolet spectrometer determined with profile measurement of bremsstrahlung continuum

    SciTech Connect

    Yamaguchi, N.; Morita, S.; Dong, C. F.; Goto, M.; Maezawa, H.; Miyauchi, H.

    2015-06-15

    The absolute calibration factor of extreme ultraviolet spectroscopic instrument which has recently been determined from absolute radiation profile measurement of bremsstrahlung continuum has been investigated by comparing the calculated diffraction efficiency of grating. An overall tendency of the wavelength dependence of the calibration factor from 40 Å to 500 Å can be reproduced by that of the grating efficiency, especially the agreement between the measured calibration factor and the calculated grating efficiency has been found to be fairly good for the wavelength range 200 Å-500 Å.

  18. Static analysis of possible emittance growth of intense charged particle beams with thermal equilibrium distribution

    SciTech Connect

    Kikuchi, Takashi; Horioka, Kazuhiko

    2009-05-15

    Possible emittance growths of intense, nonuniform beams during a transport in a focusing channel are derived as a function of nonlinear field energy and space charge tune depression factors. The nonlinear field energy of the beam with thermal equilibrium distribution is estimated by considering the particle distribution across the cross section of the beam. The results show that the possible emittance growth can be suppressed by keeping the beam particle in thermal equilibrium distribution during the beam transport.

  19. Angular distribution anisotropy of fragments ejected from methyl iodide clusters: Dependence on fs laser intensity

    NASA Astrophysics Data System (ADS)

    Karras, G.; Kosmidis, C.

    2010-10-01

    The angular distribution of the fragment ions ejected from the interaction of methyl iodide clusters with 20 fs strong laser pulses is studied by means of a mass spectrometer. Three types of angular distributions, one isotropic and two anisotropic, have been observed and their dependence on the laser intensity has been studied. There is strong evidence that the ions exhibiting anisotropic angular distribution with a maximum in the direction parallel to the laser polarization vector are produced via an electron impact ionization process.

  20. A two-parameter exponential rainfall depth-intensity distribution applied to runoff and erosion modelling

    NASA Astrophysics Data System (ADS)

    van Dijk, A. I. J. M.; Meesters, A. G. C. A.; Schellekens, J.; Bruijnzeel, L. A.

    2005-01-01

    Most runoff and erosion models require rainfall intensity data of high temporal resolution, which restricts their application and predictive potential. In this paper, a simple exponential rainfall depth-intensity distribution (ERDID) was tested, involving only two storm characteristics that are easily calculated from rainfall intensity measurements: rainfall depth ( P) and depth-averaged rainfall intensity ( Ř). This distribution fitted well to tipping bucket rainfall intensity measurements during 30 storms of 33-81 mm in West Java, Indonesia. The ERDID was used to derive analytical expressions for the hydrological model variables of two commonly used erosion models, i.e. the 'R' factor in RUSLE and normalised soil loss in GUEST. The ERDID-based expressions reproduced hydrological variables for the 30 storms with high accuracy for both models (mean difference of ±4-17% for individual storms and between -2 and 14% on aggregate). A comparison of results obtained with the original (high temporal resolution) measurements and data resampled into 5-min intervals shows that resampling had a significant effect on calculations with the original models (cumulative values were decreased by 2-26%). In some cases the use of ERDID-based expressions with distribution parameters calculated from resampled data partially corrected this underestimation. The proposed rainfall depth-intensity distribution combines physically meaningful, clearly defined variables with theoretical simplicity and high descriptive accuracy and so provides a good scope for further application in runoff and erosion modelling.

  1. Intensity Distribution of the 2011 Mw5.8 Mineral, Virginia, Earthquake

    NASA Astrophysics Data System (ADS)

    Hough, S. E.

    2011-12-01

    The Intensity distribution collected by the USGS ``Did You Feel It?'' Web site for the Mw5.8 Mineral, Virginia, earthquake, is unprecedented in its spatial richness, with over 133,000 responses received during the first week. This data can be used to investigate the nature of wave propagation and site response along the East Coast. The earthquake is further valuable as a calibration event to compare against the intensity distributions of key historical earthquakes. The distribution of intensities is consistent with earlier suggestions that wave propagation is more efficient along the (SW-NE) strike of the prevailing tectonic fabric than across it. Several small earthquakes in New York and Quebec, with magnitudes ranging from 1.8 to 3.4, appear to be remotely triggered earthquakes. I explore the statistical significance of the apparent rate increase at regional distances, but note that the distribution of inferred triggered earthquakes is roughly consistent with stronger shaking towards the northeast. The earliest remote event occurred approximately 9 hours after the mainshock; 15 located events with magnitudes 1.6-3.4 occurred in New York state and Quebec, Canada, within the first 5 days. Considering the distribution of intensities, I calculate modified Mercalli intensity residuals relative to a smooth, azimuthally-isotropic decay curve. The distribution of residuals further provides clear evidence for significant site response, for example along Chesapeake Bay and Delaware Bay, with intensities amplified by as much as two MMI units. Significant amplification is also suggested for parts of Washington DC, east of Capitol Hill. At large distances mainshock shaking was felt at many locations at distances up to 1000 km, and some locations as far as approx 1500 km. The radius of the felt distribution is roughly comparable to that of the 1895 Charleston, MO, earthquake, suggesting comparable magnitudes for the two events. I also consider the intensity distribution of the

  2. HOT ELECTRON ENERGY DISTRIBUTIONS FROM ULTRA-INTENSE LASER SOLID INTERACTIONS

    SciTech Connect

    Chen, H; Wilks, S C; Kruer, W L; Moon, S; Patel, N; Patel, P K; Shepherd, R; Snavely, R

    2005-12-08

    We present experimental data of electron energy distributions from ultra-intense (>10{sup 19} W/cm{sup 2}) laser-solid interactions using the Rutherford Appleton Laboratory Vulcan petawatt laser. These measurements were made using a CCD-based magnetic spectrometer. We present details on the distinct effective temperatures that were obtained for a wide variety of targets as a function of laser intensity. It is found that as the intensity increases from 10{sup 17} W/cm{sup 2} to 10{sup 19} W/cm{sup 2}, a 0.4 dependence on the laser intensity is found. Between 10{sup 19} W/cm{sup 2} and 10{sup 20} W/cm{sup 2}, a gradual rolling off of temperature with intensity is observed.

  3. Mapping the continuous reciprocal space intensity distribution of X-ray serial crystallography

    PubMed Central

    Yefanov, Oleksandr; Gati, Cornelius; Bourenkov, Gleb; Kirian, Richard A.; White, Thomas A.; Spence, John C. H.; Chapman, Henry N.; Barty, Anton

    2014-01-01

    Serial crystallography using X-ray free-electron lasers enables the collection of tens of thousands of measurements from an equal number of individual crystals, each of which can be smaller than 1 µm in size. This manuscript describes an alternative way of handling diffraction data recorded by serial femtosecond crystallography, by mapping the diffracted intensities into three-dimensional reciprocal space rather than integrating each image in two dimensions as in the classical approach. We call this procedure ‘three-dimensional merging’. This procedure retains information about asymmetry in Bragg peaks and diffracted intensities between Bragg spots. This intensity distribution can be used to extract reflection intensities for structure determination and opens up novel avenues for post-refinement, while observed intensity between Bragg peaks and peak asymmetry are of potential use in novel direct phasing strategies. PMID:24914160

  4. Sound radiation from an infinite elastic cylinder with dual-wave propagation-intensity distributions

    NASA Technical Reports Server (NTRS)

    Fuller, C. R.

    1988-01-01

    The radiation of sound from an elastic cylindrical shell filled with fluid and supporting multiwave propagation is studied analytically. Combinations of supersonic and subsonic shell waves are considered. The radiated field is mapped by using acoustic intensity vectors evaluated at various locations. Both time averaged and instantaneous intensity are investigated. The acoustic intensity is seen to vary markedly with axial distance down the cylinder. The effect is shown to be associated with cross terms in the intensity relations, and its magnitude and location to depend upon the relative phase and amplitudes of individual waves. Subsonic shell waves are demonstrated to interact strongly with supersonic shell waves to cause a large modification in the radiated intensity distributions near the shell surface.

  5. Intensity modulation and direct detection quantum key distribution based on quantum noise

    NASA Astrophysics Data System (ADS)

    Ikuta, Takuya; Inoue, Kyo

    2016-01-01

    Quantum key distribution (QKD) has been studied for achieving perfectly secure cryptography based on quantum mechanics. This paper presents a novel QKD scheme that is based on an intensity-modulation and direct-detection system. Two slightly intensity-modulated pulses are sent from a transmitter, and a receiver determines key bits from the directly detected intensity. We analyzed the system performance for two typical eavesdropping methods, a beam splitting attack and an intercept-resend attack, with an assumption that the transmitting and receiving devices are fully trusted. Our brief analysis showed that short- or middle-range QKD systems are achievable with a simple setup.

  6. A precise Boltzmann distribution law for the fluorescence intensity ratio of two thermally coupled levels

    NASA Astrophysics Data System (ADS)

    Qin, Feng; Zhao, Hua; Cai, Wei; Zhang, Zhiguo; Cao, Wenwu

    2016-06-01

    Noncontact monitoring temperature is very important in modern medicine, science, and technologies. The fluorescence intensity ratio (FIR) technique based on the Boltzmann distribution law exhibits excellent application potential, but the observed FIR deviates from the Boltzmann distribution law in the low temperature range. We propose a fluorescence intensity ratio relation FIR* = ηFIR by introducing a quantity η representing thermal population degree, which can be obtained from measured fluorescence decay curves of the upper emitting level. Using Eu3+ as an example, the method is confirmed that the deviated FIR is able to be corrected and return to follow the Boltzmann law.

  7. Second-order Compton-Getting effect on arbitrary intensity distribution

    NASA Technical Reports Server (NTRS)

    Ng, C. K.

    1985-01-01

    Theoretical studies of energetic particles in space are often referred to a special frame of reference. To compare theory with experiment, one has to transform the particle distribution from the special frame to the observer's frame, or vice versa. Various methods have been derived to obtain the directional distribution in the comoving frame from the directional fluxes measured on a spacecraft. These methods have become progressively complicated as increasingly detailed directional particle data become available. A set of 2nd order correct formulae for the transformation of an arbitrary differential intensity distribution, expressed as a series of spherical harmonics, between any two frames in constant relative motion is presented. These formulae greatly simplify the complicated procedures currently in use for the determination of the differential intensity distribution in a comoving frame.

  8. Resonance and non-resonance effect of continuum states of 6Li on elastic scattering angular distributions

    NASA Astrophysics Data System (ADS)

    Gómez Camacho, A.

    2016-07-01

    CDCC calculations of elastic scattering angular distributions for reactions of the weakly bound projectile 6Li with targets 28Si and 58Ni at energies around the Coulomb barrier are presented. Special emphasis is given to account for the effect of couplings from 6Li resonance states l = 2, J π = 3+, 2+, 1+. Similarly, the effect produced by non-resonant state couplings is studied. The convergent calculations are carried out with global α-target and d-target interactions. The calculated elastic scattering angular distributions are in general in good agreement with the measurements for the systems considered in this work. It is found that the calculations with only resonance states are very similar to that with all couplings (resonance+non-resonance). So, the absence of these states have a strong effect on elastic scattering (non-resonance states calculation). It is shown that the effects increase as the collision energy increases. An interpretation of the strength of the different effects is given in terms of the polarization potentials that emerge from the different couplings.

  9. Integral-moment analysis of the BATSE gamma-ray burst intensity distribution

    NASA Technical Reports Server (NTRS)

    Horack, John M.; Emslie, A. Gordon

    1994-01-01

    We have applied the technique of integral-moment analysis to the intensity distribution of the first 260 gamma-ray bursts observed by the Burst and Transient Source Experiment (BATSE) on the Compton Gamma Ray Observatory. This technique provides direct measurement of properties such as the mean, variance, and skewness of the convolved luminosity-number density distribution, as well as associated uncertainties. Using this method, one obtains insight into the nature of the source distributions unavailable through computation of traditional single parameters such as V/V(sub max)). If the luminosity function of the gamma-ray bursts is strongly peaked, giving bursts only a narrow range of luminosities, these results are then direct probes of the radial distribution of sources, regardless of whether the bursts are a local phenomenon, are distributed in a galactic halo, or are at cosmological distances. Accordingly, an integral-moment analysis of the intensity distribution of the gamma-ray bursts provides for the most complete analytic description of the source distribution available from the data, and offers the most comprehensive test of the compatibility of a given hypothesized distribution with observation.

  10. Analysis of equi-intensity curves and NU distribution of EAS

    NASA Technical Reports Server (NTRS)

    Tanahashi, G.

    1985-01-01

    The distribution of the number of muons in extensive air showers (EAS) and the equi-intensity curves of EAS are analyzed on the basis of Monte Carlo simulation of various cosmic ray composition and the interaction models. Problems in the two best combined models are discussed.

  11. Enhanced Intensity Distribution Analysis of the Rotational-Vibrational Spectrum of HCl

    ERIC Educational Resources Information Center

    Fetterolf, Monty L.

    2007-01-01

    The use of generated intensity distributions as overlays on the HCl rotational-vibrational FTIR spectrum is presented as an effective method to integrate lab work into the physical chemistry lecture. The overlays that best match the actual HCl spectrum are generated using a pre-exponential factor of 2J+2.

  12. THE COLUMN DENSITY DISTRIBUTION AND CONTINUUM OPACITY OF THE INTERGALACTIC AND CIRCUMGALACTIC MEDIUM AT REDSHIFT (z) = 2.4

    SciTech Connect

    Rudie, Gwen C.; Steidel, Charles C.; Shapley, Alice E.; Pettini, Max

    2013-06-01

    We present new high-precision measurements of the opacity of the intergalactic and circumgalactic medium (IGM; CGM) at (z) = 2.4. Using Voigt profile fits to the full Ly{alpha} and Ly{beta} forests in 15 high-resolution high-S/N spectra of hyperluminous QSOs, we make the first statistically robust measurement of the frequency of absorbers with H I column densities 14{approx}< log (N{sub H{sub I}}/cm{sup -2}){approx}<17.2. We also present the first measurements of the frequency distribution of H I absorbers in the volume surrounding high-z galaxies (the CGM, 300 pkpc), finding that the incidence of absorbers in the CGM is much higher than in the IGM. In agreement with Rudie et al., we find that there are fractionally more high-N{sub H{sub I}} absorbers than low-N{sub H{sub I}} absorbers in the CGM compared to the IGM, leading to a shallower power law fit to the CGM frequency distribution. We use these new measurements to calculate the total opacity of the IGM and CGM to hydrogen-ionizing photons, finding significantly higher opacity than most previous studies, especially from absorbers with log (N{sub H{sub I}}/cm{sup -2}) < 17.2. Reproducing the opacity measured in our data as well as the incidence of absorbers with log (N{sub H{sub I}}/cm{sup -2})>17.2 requires a broken power law parameterization of the frequency distribution with a break near N{sub H{sub I}} Almost-Equal-To 10{sup 15} cm{sup -2}. We compute new estimates of the mean free path ({lambda}{sub mfp}) to hydrogen-ionizing photons at z{sub em} = 2.4, finding {lambda}{sub mfp} = 147 {+-} 15 Mpc when considering only IGM opacity. If instead, we consider photons emanating from a high-z star-forming galaxy and account for the local excess opacity due to the surrounding CGM of the galaxy itself, the mean free path is reduced to {lambda}{sub mfp} = 121 {+-} 15 Mpc. These {lambda}{sub mfp} measurements are smaller than recent estimates and should inform future studies of the metagalactic UV background and of

  13. Energy distribution of fast electrons accelerated by high intensity laser pulse depending on laser pulse duration

    NASA Astrophysics Data System (ADS)

    Kojima, Sadaoki; Arikawa, Yasunobu; Morace, Alessio; Hata, Masayasu; Nagatomo, Hideo; Ozaki, Tetsuo; Sakata, Shohei; Lee, Seung Ho; Matsuo, Kazuki; Farley Law, King Fai; Tosaki, Shota; Yogo, Akifumi; Johzaki, Tomoyuki; Sunahara, Atsushi; Sakagami, Hitoshi; Nakai, Mitsuo; Nishimura, Hiroaki; Shiraga, Hiroyuki; Fujioka, Shinsuke; Azechi, Hiroshi

    2016-05-01

    The dependence of high-energy electron generation on the pulse duration of a high intensity LFEX laser was experimentally investigated. The LFEX laser (λ = 1.054 and intensity = 2.5 – 3 x 1018 W/cm2) pulses were focused on a 1 mm3 gold cubic block after reducing the intensities of the foot pulse and pedestal by using a plasma mirror. The full width at half maximum (FWHM) duration of the intense laser pulse could be set to either 1.2 ps or 4 ps by temporally stacking four beams of the LFEX laser, for which the slope temperature of the high-energy electron distribution was 0.7 MeV and 1.4 MeV, respectively. The slope temperature increment cannot be explained without considering pulse duration effects on fast electron generation.

  14. Re-estimating the epicenter of the 1927 Jericho earthquake using spatial distribution of intensity data

    NASA Astrophysics Data System (ADS)

    Zohar, Motti; Marco, Shmuel

    2012-07-01

    We present a new approach for re-estimating an epicenter of historical earthquake using the spatial distribution of intensity data. We use macroseismic data related to the 1927 Jericho earthquake since this is the first strong earthquake recorded by modern seismographs and is also well documented by historical evidence and reports. The epicenter is located in two sequential steps: (1) Correction of previously-evaluated seismic intensities in accordance with the local site-attributes: construction quality, topographic slope, groundwater level, and surface geology; (2) Spatial correlation of these intensities with a logarithmic variant of the epicentral distance. The resulted location (approximated to 35.5°/31.8°) is consistent with the seismogram-based location calculated by Avni et al. (2002) and also of Ben Menahem et al. (1976) with a spatial error of 50 km. The proposed method suggests an additional approach to the formers based mainly upon spatial analysis of intensity data.

  15. Reconstruction evaluation of intensity ratio distribution for extraction of absorber information in homogeneous scattering medium

    NASA Astrophysics Data System (ADS)

    Yamaoki, Toshihiko; Matoba, Osamu

    2016-02-01

    To extract effectively the absorber information embedded in a homogeneous scattering medium in the transmission geometry, a method of taking the ratio of the output intensity in a measured medium to that in a reference medium is evaluated. The reference medium is a virtual one with the same scattering coefficient distribution as that of the measured medium, but with a uniform absorption coefficient distribution. Numerical results show that the proposed method can enhance the output signal by extracting the ballistic-like component. We also apply a backprojection method to reconstruct the single absorber using many pairs of input and output intensity ratio distributions. The reconstruction position error and the quantitative measurement of absorption coefficient are discussed.

  16. A Network-Aware Distributed Storage Cache for Data Intensive Environments

    SciTech Connect

    Tierney, B.L.; Lee, J.R.; Johnston, W.E.; Crowley, B.; Holding, M.

    1999-12-23

    Modern scientific computing involves organizing, moving, visualizing, and analyzing massive amounts of data at multiple sites around the world. The technologies, the middleware services, and the architectures that are used to build useful high-speed, wide area distributed systems, constitute the field of data intensive computing. In this paper the authors describe an architecture for data intensive applications where they use a high-speed distributed data cache as a common element for all of the sources and sinks of data. This cache-based approach provides standard interfaces to a large, application-oriented, distributed, on-line, transient storage system. They describe their implementation of this cache, how they have made it network aware, and how they do dynamic load balancing based on the current network conditions. They also show large increases in application throughput by access to knowledge of the network conditions.

  17. Water and solute distributions in the soil/saprolite continuum under on-site wastewater disposal systems

    SciTech Connect

    Surbrugg, J.E.

    1992-01-01

    The expansion of housing developments in rural areas of North Carolina has created an increasing need to identify suitable soil and saprolite for on-site wastewater disposal. Physical, chemical, and hydraulic characteristics of soil and saprolite were assessed at three operating on-site wastewater disposal systems in the Piedmont region of North Carolina. The distribution patterns of selected inorganic wastewater chemicals, soil pH, and soil electrical conductivity (EC) were determined within the drainfields at all three sites. Chemical concentrations of NH[sub 4]-N, NO[sub 3]-N, NO[sub 3]-N, Ca, Mg, Na, K, and Cl in the drainfield soils were compared to background concentrations in similar soils outside each drainfield. The hydraulic performance was evaluated. Soil particle size was an important soil physical property influencing water movement, especially in the deeper C (saprolite) horizon. Specific surface area appeared to be related to CEC and inferred the possibility for limited attenuation of wastewater pollutants in coarse-textured saprolite. Lower concentrations of some inorganic chemicals in the drainfield soils were related to leaching of cations and anions by the wastewater and the low soil CEC. Significantly higher concentrations of some chemicals were found in one drainfield, presumably because of a low hydraulic conductivity in the clayey textured Bt and BC horizons, reduced nitrification rates, and higher wastewater chemical concentrations. On-site wastewater disposal systems installed in soils that are shallow to saprolite appear to function properly in treating wastewater when the soil and saprolite horizons have suitable soil textures, CEC's, and hydraulic conductivities.

  18. Drop size distributions and kinetic energy rates in variable intensity rainfall

    NASA Astrophysics Data System (ADS)

    Assouline, Shmuel

    2016-04-01

    Temporal variability in rainfall intensity reflects on the drop size distribution (DSD), and affects the rainfall kinetic energy during the event. Smith et al. (2009) reported on 1-min interval rainfall intensity and corresponding DSD variability during a storm on the 22/7/06 at Princeton, NJ. They reported also on DSDs characteristics of heavy convective rainfall events during the whole summer. Applying the DSD model of Assouline and Mualem (1997), it is shown that: (a) a similar relationship between the mean drop size and the rainfall intensity characterized the local rainfall at both the seasonal and the single storm scale; (b) using the mean drop size as a scaling factor of the DSD removes the rainfall intensity dependence at the intrastorm scale, providing a powerful tool to deal with temporal variability of rainfall rates during rainfall events. For a storm characterized by a given temporal variability of intensities, three different ways of evaluating kinetic energy per unit mass or time were applied. By comparison to estimates accounting for rainfall temporal variability and related full DSDs, representing the storm by mean intensity and drop diameter tends to overestimate kinetic energy for low intensities and underestimate it for the higher ones. The relative error for the kinetic energy per unit of mass is ±45% and shifts from negative to positive sign for I>25 mm/h. For the kinetic energy per unit of time, the relative error ranges from -100% to +210% and changes sign for I>45 mm/h. When temporal variation of intensity is accounted for but drops are characterized by their mean values instead of the full DSD, kinetic energy is underestimated by 20% on average. Consequently, accounting for temporal variability in rainfall intensity during a storm has a notable impact on the erosive power of the rainfall.

  19. Kilometric Continuum Radiation

    NASA Technical Reports Server (NTRS)

    Green, James L.; Boardsen, Scott

    2006-01-01

    Kilometric continuum (KC) is the high frequency component (approximately 100 kHz to approximately 800 kHz) of nonthermal continuum (NTC). Unlike the lower frequency portion of NTC (approximately 5 kHz to approximately 100 kHz) whose source is around the dawn sector, the source of KC occurs at all magnetic local times. The latitudinal beaming of KC as observed by GEOTAIL is, for most events, restricted to plus or minus 15 degrees magnetic latitude. KC has been observed during periods of both low and strong geomagnetic activity, with no significant correlation of wave intensity with K(sub p), index. However statistically the maximum observed frequency of KC emission tends to increase with K(sub p) index, the effect is more pronounced around solar maximum, but is also detected near solar minimum. There is strong evidence that the source region of KC is from the equatorial plasmapause during periods when a portion of the plasmapause moves significantly inwards from its nominal position. Case studies have shown that KC emissions are nearly always associated with plasmaspheric notches, shoulders, and tails. There is a recent focus on trying to understand the banded frequency structure of this emission and its relationship to plasmaspheric density ducts and irregularities in the source region.

  20. A calculation model for primary intensity distributions from cylindrically symmetric x-ray lenses

    NASA Astrophysics Data System (ADS)

    Hristov, Dimitre; Maltz, Jonathan

    2008-02-01

    A calculation model for the quantitative prediction of primary intensity fluence distributions obtained by the Bragg diffraction focusing of kilovoltage radiation by cylindrical x-ray lenses is presented. The mathematical formalism describes primary intensity distributions from cylindrically-symmetric x-ray lenses, with a planar isotropic radiation source located in a plane perpendicular to the lens axis. The presence of attenuating medium inserted between the lens and the lens focus is accounted for by energy-dependent attenuation. The influence of radiation scattered within the media is ignored. Intensity patterns are modeled under the assumption that photons that are not interacting with the lens are blocked out at any point of interest. The main characteristics of the proposed calculation procedure are that (i) the application of vector formalism allows universal treatment of all cylindrical lenses without the need of explicit geometric constructs; (ii) intensity distributions resulting from x-ray diffraction are described by a 3D generalization of the mosaic spread concept; (iii) the calculation model can be immediately coupled to x-ray diffraction simulation packages such as XOP and Shadow. Numerical simulations based on this model are to facilitate the design of focused orthovoltage treatment (FOT) systems employing cylindrical x-ray lenses, by providing insight about the influence of the x-ray source and lens parameters on quantities of dosimetric interest to radiation therapy.

  1. Near-infrared distributed feedback solgel lasers by intensity modulation and polarization modulation.

    PubMed

    Wang, Jun; Dong, Hongxing; Fan, Jintai; Li, Rihong; Zhang, Long; Wong, King Y

    2011-11-20

    Near-infrared distributed feedback (DFB) laser actions of Oxazine 725 dye in zirconia thin films and in silica bulks were investigated. Intensity modulation and polarization modulation were used to generate the DFB lasing. Wideband tuning of the output wavelength was achieved by varying the period of the modulation generated by a nanosecond Nd:YAG laser at 532 nm. Tuning ranges were 716-778 nm and 724-813 nm for the thin film lasers and the bulk lasers, respectively. The laser output showed different polarization characteristics and threshold energy variation when the feedback mechanism was changed from intensity modulation to polarization modulation. PMID:22108883

  2. Molecular photoelectron angular distributions with intense attosecond circularly polarized UV laser pulses

    NASA Astrophysics Data System (ADS)

    Yuan, Kai-Jun; Chelkowski, Szczepan; Bandrauk, André D.

    2014-01-01

    We investigate effects of intermediate resonant electronic states on molecular photoelectron angular distributions (MPADs) by intense circularly polarized attosecond UV laser pulses. Simulations are performed on aligned H2+ by numerically solving the corresponding three dimensional time dependent Schrödinger equations. MPADs exhibit signature of rotations, which is shown to be critically sensitive to the symmetry of the intermediate resonant electronic state and the pulse intensity. This sensitivity is attributed to the coherent population transfer in the initial and intermediate resonant states, thus suggesting a method to control molecular photoionization on attosecond time scale.

  3. Tennis Play Intensity Distribution and Relation with Aerobic Fitness in Competitive Players.

    PubMed

    Baiget, Ernest; Fernández-Fernández, Jaime; Iglesias, Xavier; Rodríguez, Ferran A

    2015-01-01

    The aims of this study were (i) to describe the relative intensity of simulated tennis play based on the cumulative time spent in three metabolic intensity zones, and (ii) to determine the relationships between this play intensity distribution and the aerobic fitness of a group of competitive players. 20 male players of advanced to elite level (ITN) performed an incremental on-court specific endurance tennis test to exhaustion to determine maximal oxygen uptake (VO2max) and the first and second ventilatory thresholds (VT1, VT2). Ventilatory and gas exchange parameters were monitored using a telemetric portable gas analyser (K4 b2, Cosmed, Rome, Italy). Two weeks later the participants played a simulated tennis set against an opponent of similar level. Intensity zones (1: low, 2: moderate, and 3: high) were delimited by the individual VO2 values corresponding to VT1 and VT2, and expressed as percentage of maximum VO2 and heart rate. When expressed relative to VO2max, percentage of playing time in zone 1 (77 ± 25%) was significantly higher (p < 0.001) than in zone 2 (20 ± 21%) and zone 3 (3 ± 5%). Moderate to high positive correlations were found between VT1, VT2 and VO2max, and the percentage of playing time spent in zone 1 (r = 0.68-0.75), as well as low to high inverse correlations between the metabolic variables and the percentage of time spent in zone 2 and 3 (r = -0.49-0.75). Players with better aerobic fitness play at relatively lower intensities. We conclude that players spent more than 75% of the time in their low-intensity zone, with less than 25% of the time spent at moderate to high intensities. Aerobic fitness appears to determine the metabolic intensity that players can sustain throughout the game. PMID:26098638

  4. Tennis Play Intensity Distribution and Relation with Aerobic Fitness in Competitive Players

    PubMed Central

    Baiget, Ernest; Fernández-Fernández, Jaime; Iglesias, Xavier; Rodríguez, Ferran A.

    2015-01-01

    The aims of this study were (i) to describe the relative intensity of simulated tennis play based on the cumulative time spent in three metabolic intensity zones, and (ii) to determine the relationships between this play intensity distribution and the aerobic fitness of a group of competitive players. 20 male players of advanced to elite level (ITN) performed an incremental on-court specific endurance tennis test to exhaustion to determine maximal oxygen uptake (VO2max) and the first and second ventilatory thresholds (VT1, VT2). Ventilatory and gas exchange parameters were monitored using a telemetric portable gas analyser (K4 b2, Cosmed, Rome, Italy). Two weeks later the participants played a simulated tennis set against an opponent of similar level. Intensity zones (1: low, 2: moderate, and 3: high) were delimited by the individual VO2 values corresponding to VT1 and VT2, and expressed as percentage of maximum VO2 and heart rate. When expressed relative to VO2max, percentage of playing time in zone 1 (77 ± 25%) was significantly higher (p < 0.001) than in zone 2 (20 ± 21%) and zone 3 (3 ± 5%). Moderate to high positive correlations were found between VT1, VT2 and VO2max, and the percentage of playing time spent in zone 1 (r = 0.68–0.75), as well as low to high inverse correlations between the metabolic variables and the percentage of time spent in zone 2 and 3 (r = -0.49–0.75). Players with better aerobic fitness play at relatively lower intensities. We conclude that players spent more than 75% of the time in their low-intensity zone, with less than 25% of the time spent at moderate to high intensities. Aerobic fitness appears to determine the metabolic intensity that players can sustain throughout the game. PMID:26098638

  5. Transfrontier macroseismic data exchange in NW Europe: examples of non-circular intensity distributions

    NASA Astrophysics Data System (ADS)

    Van Noten, Koen; Lecocq, Thomas; Hinzen, Klaus-G.; Sira, Christophe; Camelbeeck, Thierry

    2016-04-01

    Macroseismic data acquisition recently received a strong increase in interest due to public crowdsourcing through internet-based inquiries and real-time smartphone applications. Macroseismic analysis of felt earthquakes is important as the perception of people can be used to detect local/regional site effects in areas without instrumentation. We will demonstrate how post-processing macroseismic data improves the quality of real-time intensity evaluation of new events. Instead of using the classic DYFI representation in which internet intensities are averaged per community, we, first, geocoded all individual responses and structure the model area into 100 km2grid cells. Second, the average intensity of all answers within a grid cell is calculated. The resulting macroseismic grid cell distribution shows a less subjective and more homogeneous intensity distribution than the classical irregular community distribution and helps to improve the calculation of intensity attenuation functions. In this presentation, the 'Did You Feel It' (DYFI) macroseismic data of several >M4, e.g. the 2002 ML 4.9 Alsdorf and 2011 ML 4.3 Goch (Germany) and the 2015 ML 4.1 Ramsgate (UK), earthquakes felt in Belgium, Germany, The Netherlands, France, Luxemburg and UK are analysed. Integration of transfrontier DYFI data of the ROB-BNS, KNMI, BCSF and BGS networks results in a particular non-circular, distribution of the macroseismic data in which the felt area for all these examples extends significantly more in E-W than N-S direction. This intensity distribution cannot be explained by geometrical amplitude attenuation alone, but rather illustrates a low-pass filtering effect due to the south-to-north increasing thickness of cover sediments above the London-Brabant Massif. For the studied M4 to M5 earthquakes, the thick sediments attenuate seismic energy at higher frequencies and consequently less people feel the vibrations at the surface. This example of successful macroseismic data exchange

  6. A coordinate transformation method for calculating the 3D light intensity distribution in ICF hohlraum

    NASA Astrophysics Data System (ADS)

    Lin, Zhili; Li, Xiaoyan; Zhao, Kuixia; Chen, Xudong; Chen, Mingyu; Pu, Jixiong

    2016-06-01

    For an inertial confinement fusion (ICF) system, the light intensity distribution in the hohlraum is key to the initial plasma excitation and later laser-plasma interaction process. Based on the concept of coordinate transformation of spatial points and vector, we present a robust method with a detailed procedure that makes the calculation of the three dimensional (3D) light intensity distribution in hohlraum easily. The method is intuitive but powerful enough to solve the complex cases of random number of laser beams with arbitrary polarization states and incidence angles. Its application is exemplified in the Shenguang III Facility (SG-III) that verifies its effectiveness and it is useful for guiding the design of hohlraum structure parameter.

  7. The intensity distribution of hollow Gaussian beams focused by a lens with spherical aberration

    NASA Astrophysics Data System (ADS)

    Alkelly, Abdu A.; Al-Nadary, H.; Alhijry, Ibraheem A.

    2011-01-01

    We developed an expression that describes the hollow Gaussian beams (HGBs) passing through a spherically aberrated lens by using the Collins formula. The radial intensity distribution in both spherical aberration SA free lens, lens that exhibits relatively large in both positive spherical aberration PSA, and negative spherical aberration NSA is calculated. Numerical calculations are made and the results show that the PSA and NSA have a strong influence on the intensity distribution especially at the focus. The study showed remarkable results for which there is no hollow Gaussian beam at a large NSA along the optical axis at the focus. In addition, we found that the DSS, and wr of focused hollow Gaussian beams in the focal region depend not only on the beam radius, and beam order; but also on the spherical aberration.

  8. Molecular above-threshold-ionization angular distributions with intense circularly polarized attosecond XUV laser pulses

    NASA Astrophysics Data System (ADS)

    Yuan, Kai-Jun; Bandrauk, André D.

    2012-05-01

    Photoionization of aligned and fixed nuclei three-dimensional H2+ and two-dimensional H2 by intense circularly polarized attosecond extreme ultraviolet laser pulses is investigated from numerical solutions of the time-dependent Schrödinger equation. Molecular above-threshold-ionization angular distributions are found to be rotated with respect to the two laser perpendicular polarizations or, equivalently the symmetry axes of the molecule. The angle of rotation is critically sensitive to laser wavelength λ, photoelectron energy Een, and molecular internuclear distance R. The correlated interaction of the two electrons in H2 is shown to also influence such angular distribution rotations in different electronic states.

  9. Acoustic energy density distribution and sound intensity vector field inside coupled spaces.

    PubMed

    Meissner, Mirosław

    2012-07-01

    In this paper, the modal expansion method supported by a computer implementation has been used to predict steady-state distributions of the potential and kinetic energy densities, and the active and reactive sound intensities inside two coupled enclosures. The numerical study was dedicated to low-frequency room responses. Calculation results have shown that the distribution of energetic quantities in coupled spaces is strongly influenced by the modal localization. Appropriate descriptors of the localization effect were introduced to identify localized modes. As was evidenced by numerical data, the characteristic objects in the active intensity field are vortices positioned irregularly inside the room. It was found that vortex centers lie exactly on the lines corresponding to zeros of the eigenfunction for a dominant mode. Finally, an impact of the wall impedance on the quantitative relationship between the active and reactive intensities was analyzed and it was concluded that for very small sound damping the behavior of the sound intensity inside the room space is essentially only oscillatory. PMID:22779472

  10. Intensity and absorbed-power distribution in a cylindrical solar-pumped dye laser

    NASA Technical Reports Server (NTRS)

    Williams, M. D.

    1984-01-01

    The internal intensity and absorbed-power distribution of a simplified hypothetical dye laser of cylindrical geometry is calculated. Total absorbed power is also calculated and compared with laboratory measurements of lasing-threshold energy deposition in a dye cell to determine the suitability of solar radiation as a pump source or, alternatively, what modifications, if any, are necessary to the hypothetical system for solar pumping.

  11. Submillimeter Continuum Observations of Comets

    NASA Technical Reports Server (NTRS)

    Jewitt, David

    1998-01-01

    The aim of this proposal was to study the submillimeter continuum emission from comets. The study was based mainly on the exploitation of the world's leading submillimeter telescope, the JCMT (James Clerk Maxwell Telescope) on Mauna Kea. Submillimeter wavelengths provide a unique view of cometary physics for one main reason. The cometary size distribution is such that the scattering cross-section is dominated by small dust grains, while the mass is dominated by the largest particles. Submillimeter continuum radiation samples cometary particles much larger than those sampled by more common observations at shorter (optical and infrared) wavelengths and therefore provides a nearly direct measure of the cometary dust mass.

  12. THE GREAT OBSERVATORIES ORIGINS DEEP SURVEY: CONSTRAINTS ON THE LYMAN CONTINUUM ESCAPE FRACTION DISTRIBUTION OF LYMAN-BREAK GALAXIES AT 3.4 < z < 4.5

    SciTech Connect

    Vanzella, E.; Nonino, M.; Fontanot, F.; Cristiani, S.; Tozzi, P.; Giavalisco, M.; Inoue, A. K.; Grazian, A.; Giallongo, E.; Boutsia, K.; Fontana, A.; Pentericci, L.; Dickinson, M.; Stern, D.; Ferguson, H.; Spinrad, H.; Rosati, P.

    2010-12-10

    We use ultra-deep ultraviolet VLT/VIMOS intermediate-band and VLT/FORS1 narrowband imaging in the GOODS Southern field to derive limits on the distribution of the escape fraction (f{sub esc}) of ionizing radiation for L {>=} L*{sub z=3} Lyman-break galaxies (LBGs) at redshift 3.4-4.5. Only one LBG, at redshift z = 3.795, is detected in its Lyman continuum (LyC; S/N {approx_equal} 5.5), the highest redshift galaxy currently known with a direct detection. Its ultraviolet morphology is quite compact (R{sub eff} = 0.8 kpc physical). Three out of seven active galactic nuclei are also detected in their LyC, including one at redshift z = 3.951 and z{sub 850} = 26.1. From stacked data (LBGs), we set an upper limit to the average f{sub esc} in the range 5%-20%, depending on how the data are selected (e.g., by magnitude and/or redshift). We undertake extensive Monte Carlo simulations that take into account intergalactic attenuation, stellar population synthesis models, dust extinction, and photometric noise in order to explore the moments of the distribution of the escaping radiation. Various distributions (exponential, log-normal, and Gaussian) are explored. We find that the median f{sub esc} is lower than {approx_equal}6% with an 84% percentile limit not larger than 20%. If this result remains valid for fainter LBGs down to current observational limits, then the LBG population might be not sufficient to account for the entire photoionization budget at the redshifts considered here, with the exact details dependent upon the assumed ionizing background and QSO contribution thereto. It is possible that f{sub esc} depends on the UV luminosity of the galaxies, with fainter galaxies having higher f{sub esc}, and estimates of f{sub esc} from a sample of faint LBGs from HUDF (i{sub 775} {<=}28.5) are in broad quantitative agreement with such a scenario.

  13. Impact of Hydrologic Variability on Nutrient Age Distribution in Intensively Managed Landscapes

    NASA Astrophysics Data System (ADS)

    Kumar, P.; Woo, D. K.

    2014-12-01

    The distribution, concentration, and transport of nutrients in agricultural landscapes are of significant societal concern. Our interests in reactive nitrogen and the nitrogen cycle have shifted from increasing the efficiency of nitrogen delivery to target crop species to decreasing environmental damage caused by intensive agricultural practices. Enhancing the reactive nitrogen use efficiency to increase food production to meet future demand inevitably contributes to an increase in the reactive nitrogen load in the ecosystem, and damaging the environment. However, due to the complexity of the nitrogen cycle, the dynamics of nitrogen in soils and its interactions with ecohydrological processes at the watershed and regional scales are not well understood to enable adequate remedial measures. To unravel the complexity of this dynamics we have developed a model for characterizing the nitrogen age (elapsed time) distribution. The goal of our study is to develop and analyze the dynamics of nitrogen in the context of age and transit times resulting from advection, mixing, and production/destruction processes; evaluate the effects of micro-topographic variability on the nitrogen age distributions; and investigate how the temporal dynamics of the nitrogen age distribution are affected by changes in the variability of climate drivers. Our study is performed for the Upper Sangamon River Basin in the Critical Zone Observatory for Intensively Managed Landscapes (IML-CZO).

  14. Photoionization branching ratios and vibrational intensity distribution for N2, CO; and CO2 between 53 and 75 nm

    NASA Technical Reports Server (NTRS)

    Samson, J. A. R.; Gardner, J. L.

    1973-01-01

    The probability of radiation producing ions in specific electronic and vibrational levels was documented. For example, when a narrow band-pass of solar ionizing photons is incident on an atmospheric species it is now possible to describe, accurately, how the radiant energy is shared among the various electronic states of the ions produced. The molecules studied were N2, CO, and CO2. These molecules were photoionized by radiation between 53 and 75 nm. The effects of autoionization are discussed and continuum vibrational intensities are tabulated and compared with theoretical Franck-Condon factors where available. The branching ratios and partial cross sections for ionization into various electronic states are tabulated.

  15. Income Disparities and the Global Distribution of Intensively Farmed Chicken and Pigs

    PubMed Central

    Gilbert, Marius; Conchedda, Giulia; Van Boeckel, Thomas P.; Cinardi, Giuseppina; Linard, Catherine; Nicolas, Gaëlle; Thanapongtharm, Weerapong; D'Aietti, Laura; Wint, William; Newman, Scott H.; Robinson, Timothy P.

    2015-01-01

    The rapid transformation of the livestock sector in recent decades brought concerns on its impact on greenhouse gas emissions, disruptions to nitrogen and phosphorous cycles and on land use change, particularly deforestation for production of feed crops. Animal and human health are increasingly interlinked through emerging infectious diseases, zoonoses, and antimicrobial resistance. In many developing countries, the rapidity of change has also had social impacts with increased risk of marginalisation of smallholder farmers. However, both the impacts and benefits of livestock farming often differ between extensive (backyard farming mostly for home-consumption) and intensive, commercial production systems (larger herd or flock size, higher investments in inputs, a tendency towards market-orientation). A density of 10,000 chickens per km2 has different environmental, epidemiological and societal implications if these birds are raised by 1,000 individual households or in a single industrial unit. Here, we introduce a novel relationship that links the national proportion of extensively raised animals to the gross domestic product (GDP) per capita (in purchasing power parity). This relationship is modelled and used together with the global distribution of rural population to disaggregate existing 10 km resolution global maps of chicken and pig distributions into extensive and intensive systems. Our results highlight countries and regions where extensive and intensive chicken and pig production systems are most important. We discuss the sources of uncertainties, the modelling assumptions and ways in which this approach could be developed to forecast future trajectories of intensification. PMID:26230336

  16. Income Disparities and the Global Distribution of Intensively Farmed Chicken and Pigs.

    PubMed

    Gilbert, Marius; Conchedda, Giulia; Van Boeckel, Thomas P; Cinardi, Giuseppina; Linard, Catherine; Nicolas, Gaëlle; Thanapongtharm, Weerapong; D'Aietti, Laura; Wint, William; Newman, Scott H; Robinson, Timothy P

    2015-01-01

    The rapid transformation of the livestock sector in recent decades brought concerns on its impact on greenhouse gas emissions, disruptions to nitrogen and phosphorous cycles and on land use change, particularly deforestation for production of feed crops. Animal and human health are increasingly interlinked through emerging infectious diseases, zoonoses, and antimicrobial resistance. In many developing countries, the rapidity of change has also had social impacts with increased risk of marginalisation of smallholder farmers. However, both the impacts and benefits of livestock farming often differ between extensive (backyard farming mostly for home-consumption) and intensive, commercial production systems (larger herd or flock size, higher investments in inputs, a tendency towards market-orientation). A density of 10,000 chickens per km2 has different environmental, epidemiological and societal implications if these birds are raised by 1,000 individual households or in a single industrial unit. Here, we introduce a novel relationship that links the national proportion of extensively raised animals to the gross domestic product (GDP) per capita (in purchasing power parity). This relationship is modelled and used together with the global distribution of rural population to disaggregate existing 10 km resolution global maps of chicken and pig distributions into extensive and intensive systems. Our results highlight countries and regions where extensive and intensive chicken and pig production systems are most important. We discuss the sources of uncertainties, the modelling assumptions and ways in which this approach could be developed to forecast future trajectories of intensification. PMID:26230336

  17. Experimental verification of a model describing the intensity distribution from a single mode optical fiber

    SciTech Connect

    Moro, Erik A; Puckett, Anthony D; Todd, Michael D

    2011-01-24

    The intensity distribution of a transmission from a single mode optical fiber is often approximated using a Gaussian-shaped curve. While this approximation is useful for some applications such as fiber alignment, it does not accurately describe transmission behavior off the axis of propagation. In this paper, another model is presented, which describes the intensity distribution of the transmission from a single mode optical fiber. A simple experimental setup is used to verify the model's accuracy, and agreement between model and experiment is established both on and off the axis of propagation. Displacement sensor designs based on the extrinsic optical lever architecture are presented. The behavior of the transmission off the axis of propagation dictates the performance of sensor architectures where large lateral offsets (25-1500 {micro}m) exist between transmitting and receiving fibers. The practical implications of modeling accuracy over this lateral offset region are discussed as they relate to the development of high-performance intensity modulated optical displacement sensors. In particular, the sensitivity, linearity, resolution, and displacement range of a sensor are functions of the relative positioning of the sensor's transmitting and receiving fibers. Sensor architectures with high combinations of sensitivity and displacement range are discussed. It is concluded that the utility of the accurate model is in its predicative capability and that this research could lead to an improved methodology for high-performance sensor design.

  18. Impacts of Fog Characteristics, Forward Illumination, and Warning Beacon Intensity Distribution on Roadway Hazard Visibility

    PubMed Central

    2016-01-01

    Warning beacons are critical for the safety of transportation, construction, and utility workers. These devices need to produce sufficient luminous intensity to be visible without creating glare to drivers. Published standards for the photometric performance of warning beacons do not address their performance in conditions of reduced visibility such as fog. Under such conditions light emitted in directions other than toward approaching drivers can create scattered light that makes workers and other hazards less visible. Simulations of visibility of hazards under varying conditions of fog density, forward vehicle lighting, warning beacon luminous intensity, and intensity distribution were performed to assess their impacts on visual performance by drivers. Each of these factors can influence the ability of drivers to detect and identify workers and hazards along the roadway in work zones. Based on the results, it would be reasonable to specify maximum limits on the luminous intensity of warning beacons in directions that are unlikely to be seen by drivers along the roadway, limits which are not included in published performance specifications. PMID:27314058

  19. The training intensity distribution among well-trained and elite endurance athletes

    PubMed Central

    Stöggl, Thomas L.; Sperlich, Billy

    2015-01-01

    Researchers have retrospectively analyzed the training intensity distribution (TID) of nationally and internationally competitive athletes in different endurance disciplines to determine the optimal volume and intensity for maximal adaptation. The majority of studies present a “pyramidal” TID with a high proportion of high volume, low intensity training (HVLIT). Some world-class athletes appear to adopt a so-called “polarized” TID (i.e., significant % of HVLIT and high-intensity training) during certain phases of the season. However, emerging prospective randomized controlled studies have demonstrated superior responses of variables related to endurance when applying a polarized TID in well-trained and recreational individuals when compared with a TID that emphasizes HVLIT or threshold training. The aims of the present review are to: (1) summarize the main responses of retrospective and prospective studies exploring TID; (2) provide a systematic overview on TIDs during preparation, pre-competition, and competition phases in different endurance disciplines and performance levels; (3) address whether one TID has demonstrated greater efficacy than another; and (4) highlight research gaps in an effort to direct future scientific studies. PMID:26578968

  20. Impacts of Fog Characteristics, Forward Illumination, and Warning Beacon Intensity Distribution on Roadway Hazard Visibility.

    PubMed

    Bullough, John D; Rea, Mark S

    2016-01-01

    Warning beacons are critical for the safety of transportation, construction, and utility workers. These devices need to produce sufficient luminous intensity to be visible without creating glare to drivers. Published standards for the photometric performance of warning beacons do not address their performance in conditions of reduced visibility such as fog. Under such conditions light emitted in directions other than toward approaching drivers can create scattered light that makes workers and other hazards less visible. Simulations of visibility of hazards under varying conditions of fog density, forward vehicle lighting, warning beacon luminous intensity, and intensity distribution were performed to assess their impacts on visual performance by drivers. Each of these factors can influence the ability of drivers to detect and identify workers and hazards along the roadway in work zones. Based on the results, it would be reasonable to specify maximum limits on the luminous intensity of warning beacons in directions that are unlikely to be seen by drivers along the roadway, limits which are not included in published performance specifications. PMID:27314058

  1. Mapping the energy distribution of SERRS hot spots from anti-Stokes to Stokes intensity ratios.

    PubMed

    dos Santos, Diego P; Temperini, Marcia L A; Brolo, Alexandre G

    2012-08-15

    The anomalies in the anti-Stokes to Stokes intensity ratios in single-molecule surface-enhanced resonance Raman scattering were investigated. Brilliant green and crystal violet dyes were the molecular probes, and the experiments were carried out on an electrochemically activated Ag surface. The results allowed new insights into the origin of these anomalies and led to a new method to confirm the single-molecule regime in surface-enhanced Raman scattering. Moreover, a methodology to estimate the distribution of resonance energies that contributed to the imbalance in the anti-Stokes to Stokes intensity ratios at the electromagnetic hot spots was proposed. This method allowed the local plasmonic resonance energies on the metallic surface to be spatially mapped. PMID:22804227

  2. The enhanced measurement-device-independent quantum key distribution with two-intensity decoy states

    NASA Astrophysics Data System (ADS)

    Zhu, Jian-Rong; Zhu, Feng; Zhou, Xing-Yu; Wang, Qin

    2016-06-01

    We put forward a new scheme for implementing the measurement-device-independent quantum key distribution (QKD) with weak coherent source, while using only two different intensities. In the new scheme, we insert a beam splitter and a local detector at both Alice's and Bob's side, and then all the triggering and non-triggering signals could be employed to process parameter estimations, resulting in very precise estimations for the two-single-photon contributions. Besides, we compare its behavior with two other often used methods, i.e., the conventional standard three-intensity decoy-state measurement-device-independent QKD and the passive measurement-device-independent QKD. Through numerical simulations, we demonstrate that our new approach can exhibit outstanding characteristics not only in the secure transmission distance, but also in the final key generation rate.

  3. Rotations of molecular photoelectron angular distributions with intense ultrashort circularly polarized attosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Yuan, Kai-Jun; Chelkowski, Szczepan; Bandrauk, André D.

    2013-04-01

    Molecular photoelectron angular distributions (MPADs) by intense (I0 ⩾ 1014 W/cm2) circularly polarized ultrashort, few cycle (attosecond) ultraviolet laser pulses are presented from numerical solutions of time dependent Schrödinger equations. For the aligned molecular ion H_2^+, the MPADs exhibit rotations with respect to the polarization and molecular symmetry axes which are determined by the symmetry of the initial electronics states. It is also found that the rotation angle of MPADs is insensitive to the pulse intensity. We attribute these effects to the asymmetry between the parallel and perpendicular (to the molecular axis) polarization photoionization. Influence of the molecular alignment and ionizing pulse ellipticity on the rotation of MPADs is also shown to allow control of the nonsymmetric ionization.

  4. HOT ELECTRON ENERGY DISTRIBUTIONS FROM ULTRA-INTENSE LASER SOLID INTERACTIONS

    SciTech Connect

    Chen, H; Wilks, S C; Kruer, W; Patel, P; Shepherd, R

    2008-10-08

    Measurements of electron energy distributions from ultra-intense (>10{sup 19} W/cm{sup 2}) laser-solid interactions using an electron spectrometer are presented. These measurements were performed on the Vulcan petawatt laser at Rutherford Appleton Laboratory and the Callisto laser at Lawrence Livermore National Laboratory. The effective hot electron temperatures (T{sub hot}) have been measured for laser intensities (I{lambda}{sup 2}) from 10{sup 18} W/cm{sup 2} {micro}m{sup 2} to 10{sup 21} W/cm{sup 2} {micro}m{sup 2} for the first time, and T{sub hot} is found to increase as (I{lambda}{sup 2}){sup 0.34} {+-} 0.4. This scaling agrees well with the empirical scaling published by Beg et al. (1997), and is explained by a simple physical model that gives good agreement with experimental results and particle-in-cell simulations.

  5. Correlation of Red Blood Cell Aggregate Size with Transmitted Light Intensity Distributions

    NASA Astrophysics Data System (ADS)

    Hitt, Darren L.

    1998-11-01

    Under sufficiently low shear rates, such as those encountered in the microcirculation, human red blood cells are known to form aggregate structures (`rouleaux'). These aggregates may range in size from a simple chain containing only a few cells to complex three-dimensional structures containing tens of cells. Previous studies have attempted to characterize the aggregate size by examining the spatial distribution of transmitted light intensity resulting from transillumination of the blood flow. For experiments performed in vitro and in vivo, spectral analysis of the transmitted light intensities has shown that the presence of aggregates in the flow can linked with an increase in the spectral power at small wavenumbers. The magnitudes of the affected wavenumbers correspond to structures considerably larger than individual cells. A precise numerical correlation, however, is difficult to establish. In this work, computer simulations of aggregating blood flow are used along with statistical considerations in an attempt to better correlate the observed spectral trends with actual aggregate size.

  6. The Interannual Stability of Cumulative Frequency Distributions for Convective System Size and Intensity

    NASA Technical Reports Server (NTRS)

    Mohr, Karen I.; Molinari, John; Thorncroft, Chris D,

    2010-01-01

    The characteristics of convective system populations in West Africa and the western Pacific tropical cyclone basin were analyzed to investigate whether interannual variability in convective activity in tropical continental and oceanic environments is driven by variations in the number of events during the wet season or by favoring large and/or intense convective systems. Convective systems were defined from TRMM data as a cluster of pixels with an 85 GHz polarization-corrected brightness temperature below 255 K and with an area at least 64 km 2. The study database consisted of convective systems in West Africa from May Sep for 1998-2007 and in the western Pacific from May Nov 1998-2007. Annual cumulative frequency distributions for system minimum brightness temperature and system area were constructed for both regions. For both regions, there were no statistically significant differences among the annual curves for system minimum brightness temperature. There were two groups of system area curves, split by the TRMM altitude boost in 2001. Within each set, there was no statistically significant interannual variability. Sub-setting the database revealed some sensitivity in distribution shape to the size of the sampling area, length of sample period, and climate zone. From a regional perspective, the stability of the cumulative frequency distributions implied that the probability that a convective system would attain a particular size or intensity does not change interannually. Variability in the number of convective events appeared to be more important in determining whether a year is wetter or drier than normal.

  7. Intensity and polarization of light scattered by size distributions of randomly oriented nonspherical particles

    NASA Technical Reports Server (NTRS)

    Mishchenko, M. I.; Travis, L. D.

    1993-01-01

    Calculations of light scattering by small particles are important in many diverse fields of science and engineering. In many cases of practical interest, scattering particles are nonspherical and are distributed over sizes and orientations. However, accurate light scattering computations for ensembles of nonspherical particles are difficult and time-consuming, and the literature in which such calculations are reported is rather scarce. In this paper, the T-matrix approach, as extended recently to randomly oriented particles, is used to calculate rigorously light scattering by size distributions of randomly oriented axially symmetric particles. To model the variation of particle sizes in real ensembles, we use a power law distribution typical of some terrestrial aerosols. Contour plots of intensity and degree of linear polarization for polydisperse prolate and oblate spheroids of different aspect ratios and effective equivalent-sphere size parameters from 0 to 10 are calculated and compared with calculations for equivalent spheres. The angular scattering behavior of nonspherical polydispersions is found to be greatly different from that of spheres, while the scattering properties of oblate and prolate spheroids of the same aspect ratio are similar. With increasing particle size, both intensity and polarization become more shape-dependent. In general, nonspherical particles are stronger side scatterers and weaker backscatterers than equivalent spheres. With increasing aspect ratio of nonspherical particles polarization tends to be predominantly positive. Possible effects of particle nonsphericity on optical remote sensing of atmospheric aerosols are discussed.

  8. Mercury distribution in a mangrove tidal creek affected by intensive shrimp farming.

    PubMed

    Costa, B G B; Soares, T M; Torres, R F; Lacerda, L D

    2013-05-01

    In this study, the Hg distributions in water and sediments from a mangrove creek that receives intensive shrimp farming effluents were determined. The average dissolved and particulate Hg concentrations in the water varied from 3.1 to 9.2 ng L(-1) and from 4.4 to 9.4 ng L(-1), respectively. However, the Hg concentrations in the suspended particulate matter and the bottom sediments varied from 95.4 to 115.7 ng g(-1) and from 1.6 to 10.3 ng g(-1), respectively. A Ward quadratic distance cluster analysis based on the Hg concentrations and hydro- and geochemical parameters (oxygen, salinity, temperature, pH, and organic matter and aluminum content) showed the effects of shrimp farming effluents on the Hg distribution pattern. Furthermore, these results were supported by the Hg distribution in the sediment cores. This study emphasizes the necessity of including Hg as a potential pollutant when monitoring the environmental impacts of intensive shrimp farming. PMID:23370694

  9. Effect of Air-Sea coupling on the Frequency Distribution of Intense Tropical Cyclones over the Northwestern Pacific

    NASA Astrophysics Data System (ADS)

    Ogata, Tomomichi; Mizuta, Ryo; Adachi, Yukimasa; Murakami, Hiroyuki; Ose, Tomomaki

    2016-04-01

    Effect of air-sea coupling on the frequency distribution of intense tropical cyclones (TCs) over the northwestern Pacific (NWP) region is investigated using an atmosphere and ocean coupled general circulation model (AOGCM). Monthly varying flux adjustment enables AOGCM to simulate both subseasonal air-sea interaction and realistic seasonal to interannual SST variability. The maximum of intense TC distribution around 20-30°N in the AGCM shifts equatorward in the AOGCM due to the air-sea coupling. Hence AOGCM reduces northward intense TC distribution bias seen in AGCM. Over the NWP, AOGCM-simulated SST variability is large around 20-30°N where the warm mixed layer becomes shallower rapidly. Active entrainment from subsurface water over this region causes stronger SST cooling and hence TC intensity decreases. These results suggest that air-sea coupling characterized by subsurface oceanic condition causes more realistic distribution of intense TCs over the NWP.

  10. Effect of air-sea coupling on the frequency distribution of intense tropical cyclones over the northwestern Pacific

    NASA Astrophysics Data System (ADS)

    Ogata, Tomomichi; Mizuta, Ryo; Adachi, Yukimasa; Murakami, Hiroyuki; Ose, Tomoaki

    2015-12-01

    Effect of air-sea coupling on the frequency distribution of intense tropical cyclones (TCs) over the northwestern Pacific (NWP) region is investigated using an atmosphere and ocean coupled general circulation model (AOGCM). Monthly varying flux adjustment enables AOGCM to simulate both subseasonal air-sea interaction and realistic seasonal to interannual sea surface temperature (SST) variability. The maximum of intense TC distribution around 20-30°N in the AGCM shifts equatorward in the AOGCM due to the air-sea coupling. Hence, AOGCM reduces northward intense TC distribution bias seen in AGCM. Over the NWP, AOGCM-simulated SST variability is large around 20-30°N where the warm mixed layer becomes shallower rapidly. Active entrainment from subsurface water over this region causes stronger SST cooling, and hence, TC intensity decreases. These results suggest that air-sea coupling characterized by subsurface oceanic condition causes more realistic distribution of intense TCs over the NWP.

  11. Molecular photoelectron momentum distributions by intense orthogonally polarized attosecond ultraviolet laser pulses

    NASA Astrophysics Data System (ADS)

    Yuan, Kai-Jun; Chelkowski, Szczepan; Bandrauk, André D.

    2015-10-01

    We study molecular photoelectron momentum distributions (MPMDs) of aligned H2+ by intense orthogonally polarized attosecond ultraviolet laser pulses. Photoionization is simulated by numerically solving corresponding three-dimensional time dependent Schrödinger equations with static nuclei. It is found that altering pulse phases ϕ varies the structure of MPMDs, which is attributed to the interference effect between orthogonal polarization ionizations. The phase ϕ dependent MPMDs are also a function of molecular alignment and pulse wavelengths. Altering the symmetry of initial electronic states offers the possibility of imaging molecular orbitals by orthogonal polarization attosecond MPMDs.

  12. Target micro-displacement measurement by a "comb" structure of intensity distribution in laser plasma propulsion

    NASA Astrophysics Data System (ADS)

    Zheng, Z. Y.; Zhang, S. Q.; Gao, L.; Gao, H.

    2015-05-01

    A "comb" structure of beam intensity distribution is designed and achieved to measure a target displacement of micrometer level in laser plasma propulsion. Base on the "comb" structure, the target displacement generated by nanosecond laser ablation solid target is measured and discussed. It is found that the "comb" structure is more suitable for a thin film target with a velocity lower than tens of millimeters per second. Combing with a light-electric monitor, the `comb' structure can be used to measure a large range velocity.

  13. Continuum emission in the 1980 July 1 solar flare

    NASA Technical Reports Server (NTRS)

    Zirin, H.; Neidig, D. F.

    1981-01-01

    Comparison of continuum measurements of the July 1, 1980 flare at Big Bear Solar Observatory and Sacramento Peak Observatory show strong blue emission kernels with the ratio of Balmer continuum (Bac):3862 A continuum:continuum above 4275 A to be about 10:5:1. The blue continuum at 3862 A is too strong to be explained by unresolved lines. The Bac intensity was 2.5 times the photosphere and the strongest 3826 A continuum was 2 times the photosphere. The brightest continuum kernel occurred late in the flare, after the hard X-ray peak and related in time to an isolated peak in the 2.2 MeV line, suggesting that that continuum was excited by protons above 20 MeV.

  14. Predicting photoemission intensities and angular distributions with real-time density-functional theory

    NASA Astrophysics Data System (ADS)

    Dauth, M.; Kümmel, S.

    2016-02-01

    Photoemission spectroscopy is one of the most frequently used tools for characterizing the electronic structure of condensed matter systems. We discuss a scheme for simulating photoemission from finite systems based on time-dependent density-functional theory. It allows for the first-principles calculation of relative electron binding energies, ionization cross sections, and anisotropy parameters. We extract these photoemission spectroscopy observables from Kohn-Sham orbitals propagated in real time. We demonstrate that the approach is capable of estimating photoemission intensities, i.e., peak heights. It can also reliably predict the angular distribution of photoelectrons. For the example of benzene we contrast calculated angular distribution anisotropy parameters to experimental reference data. Self-interaction free Kohn-Sham theory yields meaningful outer valence single-particle states in the right energetic order. We discuss how to properly choose the complex absorbing potential that is used in the simulations.

  15. Continuum radiation in planetary magnetospheres

    NASA Technical Reports Server (NTRS)

    Kurth, W. S.

    1991-01-01

    With the completion of the Voyager tour of the outer planets, radio and plasma wave instruments have executed the first survey of the wave spectra of Earth, Jupiter, Saturn, Uranus, and Neptune. One of the most notable conclusions of this survey is that there is a great deal of qualitative similarity in both the plasma wave and radio wave spectra from one magnetosphere to the next. In particular, in spite of detailed differences, most of the radio emissions at each of the planets have been tentatively classified into two primary categories. First, the most intense emissions are generally associated with the cyclotron maser instability. Second, a class of weaker emissions can be found at each of the magnetospheres which appears to be the result of conversion from intense electrostatic emissions at the upper hybrid resonance frequency into (primarily) ordinary mode radio emission. It is this second category, often referred to as nonthermal continuum radiation, which we will discuss in this review. We review the characteristics of the continuum spectrum at each of the planets, discuss the source region and direct observations of the generation of the emissions where available, and briefly describe the theories for the generation of the emissions. Over the past few years evidence has increased that the linear mode conversion of electrostatic waves into the ordinary mode can account for at least some of the continuum radiation observed. There is no definitive evidence which precludes the possibility that a nonlinear mechanism may also be important.

  16. The Suicide Prevention Continuum

    PubMed Central

    Caldwell, Dawn

    2010-01-01

    The suicide prevention continuum illustrates a practical approach to the complex issue of suicide prevention. The continuum evolved from discussions with two Aboriginal communities in Atlantic Canada about suicide and the different types of interventions available. The continuum offers a framework and reference tool to differentiate between the different stages of suicide risk. It illustrates where the Aboriginal Community Youth Resilience Network (ACYRN) fits into suicide prevention and how it contributes to prevention knowledge, capacity building, and policy development. PMID:20835376

  17. Derivation from first principles of the statistical distribution of the mass peak intensities of MS data.

    PubMed

    Ipsen, Andreas

    2015-02-01

    Despite the widespread use of mass spectrometry (MS) in a broad range of disciplines, the nature of MS data remains very poorly understood, and this places important constraints on the quality of MS data analysis as well as on the effectiveness of MS instrument design. In the following, a procedure for calculating the statistical distribution of the mass peak intensity for MS instruments that use analog-to-digital converters (ADCs) and electron multipliers is presented. It is demonstrated that the physical processes underlying the data-generation process, from the generation of the ions to the signal induced at the detector, and on to the digitization of the resulting voltage pulse, result in data that can be well-approximated by a Gaussian distribution whose mean and variance are determined by physically meaningful instrumental parameters. This allows for a very precise understanding of the signal-to-noise ratio of mass peak intensities and suggests novel ways of improving it. Moreover, it is a prerequisite for being able to address virtually all data analytical problems in downstream analyses in a statistically rigorous manner. The model is validated with experimental data. PMID:25620060

  18. Vertical distribution of precipitation particles in Baiu frontal stratiform intense rainfall around Okinawa Island, Japan

    NASA Astrophysics Data System (ADS)

    Oue, M.; Ohigashi, T.; Tsuboki, K.; Nakakita, E.

    2015-06-01

    The vertical distribution of precipitation particles in an intensely precipitating stratiform cloud associated with the Baiu front around Okinawa Island was observed. X-band polarimetric radar, disdrometer, and hydrometeor videosonde data were used to examine the precipitation processes. The cloud top was approximately 12 km above sea level, as convection was depressed while stratiform regions developed near Okinawa Island. In the rain region below 3 km, the mean median volume diameter of the raindrop size distribution (DSD) estimated from the radar variables was 1.55 mm, and the mean normalized intercept parameter was 104.12 mm-1 m-3 with a mean radar reflectivity of 40.5 dBZe. The DSD indicates that the stratiform precipitation was characterized by higher number concentrations of smaller drops than observed previously in convective cells in a Baiu frontal convective precipitation region around Okinawa Island. The DSD also suggests the presence of larger raindrops than in convective cells embedded in a Baiu frontal stratiform precipitation region around Okinawa Island. In the ice region at 5-6 km, just above the melting layer and 6 km below the cloud top, the differential reflectivity and specific differential phase showed positive values, and videosonde measurements revealed that the number concentration of column-, plate-, and capped-column-like crystals (maximum dimensions of ≥0.1 mm) was 112 L-1. The high number concentration of these crystals contributed to the intense stratiform rainfall associated with the Baiu front.

  19. The role of precipitation type, intensity, and spatial distribution in source water quality after wildfire

    USGS Publications Warehouse

    Murphy, Sheila F.; Writer, Jeffrey H.; McCleskey, R. Blaine; Martin, Deborah A.

    2015-01-01

    Storms following wildfires are known to impair drinking water supplies in the southwestern United States, yet our understanding of the role of precipitation in post-wildfire water quality is far from complete. We quantitatively assessed water-quality impacts of different hydrologic events in the Colorado Front Range and found that for a three-year period, substantial hydrologic and geochemical responses downstream of a burned area were primarily driven by convective storms with a 30 min rainfall intensity >10 mm h−1. These storms, which typically occur several times each year in July–September, are often small in area, short-lived, and highly variable in intensity and geographic distribution. Thus, a rain gage network with high temporal resolution and spatial density, together with high-resolution stream sampling, are required to adequately characterize post-wildfire responses. We measured total suspended sediment, dissolved organic carbon (DOC), nitrate, and manganese concentrations that were 10–156 times higher downstream of a burned area compared to upstream during relatively common (50% annual exceedance probability) rainstorms, and water quality was sufficiently impaired to pose water-treatment concerns. Short-term water-quality impairment was driven primarily by increased surface runoff during higher intensity convective storms that caused erosion in the burned area and transport of sediment and chemical constituents to streams. Annual sediment yields downstream of the burned area were controlled by storm events and subsequent remobilization, whereas DOC yields were closely linked to annual runoff and thus were more dependent on interannual variation in spring runoff. Nitrate yields were highest in the third year post-wildfire. Results from this study quantitatively demonstrate that water quality can be altered for several years after wildfire. Because the southwestern US is prone to wildfires and high-intensity rain storms, the role of storms in post

  20. The role of precipitation type, intensity, and spatial distribution in source water quality after wildfire

    NASA Astrophysics Data System (ADS)

    Murphy, Sheila F.; Writer, Jeffrey H.; Blaine McCleskey, R.; Martin, Deborah A.

    2015-08-01

    Storms following wildfires are known to impair drinking water supplies in the southwestern United States, yet our understanding of the role of precipitation in post-wildfire water quality is far from complete. We quantitatively assessed water-quality impacts of different hydrologic events in the Colorado Front Range and found that for a three-year period, substantial hydrologic and geochemical responses downstream of a burned area were primarily driven by convective storms with a 30 min rainfall intensity >10 mm h-1. These storms, which typically occur several times each year in July-September, are often small in area, short-lived, and highly variable in intensity and geographic distribution. Thus, a rain gage network with high temporal resolution and spatial density, together with high-resolution stream sampling, are required to adequately characterize post-wildfire responses. We measured total suspended sediment, dissolved organic carbon (DOC), nitrate, and manganese concentrations that were 10-156 times higher downstream of a burned area compared to upstream during relatively common (50% annual exceedance probability) rainstorms, and water quality was sufficiently impaired to pose water-treatment concerns. Short-term water-quality impairment was driven primarily by increased surface runoff during higher intensity convective storms that caused erosion in the burned area and transport of sediment and chemical constituents to streams. Annual sediment yields downstream of the burned area were controlled by storm events and subsequent remobilization, whereas DOC yields were closely linked to annual runoff and thus were more dependent on interannual variation in spring runoff. Nitrate yields were highest in the third year post-wildfire. Results from this study quantitatively demonstrate that water quality can be altered for several years after wildfire. Because the southwestern US is prone to wildfires and high-intensity rain storms, the role of storms in post

  1. Interpolating Non-Parametric Distributions of Hourly Rainfall Intensities Using Random Mixing

    NASA Astrophysics Data System (ADS)

    Mosthaf, Tobias; Bárdossy, András; Hörning, Sebastian

    2015-04-01

    The correct spatial interpolation of hourly rainfall intensity distributions is of great importance for stochastical rainfall models. Poorly interpolated distributions may lead to over- or underestimation of rainfall and consequently to wrong estimates of following applications, like hydrological or hydraulic models. By analyzing the spatial relation of empirical rainfall distribution functions, a persistent order of the quantile values over a wide range of non-exceedance probabilities is observed. As the order remains similar, the interpolation weights of quantile values for one certain non-exceedance probability can be applied to the other probabilities. This assumption enables the use of kernel smoothed distribution functions for interpolation purposes. Comparing the order of hourly quantile values over different gauges with the order of their daily quantile values for equal probabilities, results in high correlations. The hourly quantile values also show high correlations with elevation. The incorporation of these two covariates into the interpolation is therefore tested. As only positive interpolation weights for the quantile values assure a monotonically increasing distribution function, the use of geostatistical methods like kriging is problematic. Employing kriging with external drift to incorporate secondary information is not applicable. Nonetheless, it would be fruitful to make use of covariates. To overcome this shortcoming, a new random mixing approach of spatial random fields is applied. Within the mixing process hourly quantile values are considered as equality constraints and correlations with elevation values are included as relationship constraints. To profit from the dependence of daily quantile values, distribution functions of daily gauges are used to set up lower equal and greater equal constraints at their locations. In this way the denser daily gauge network can be included in the interpolation of the hourly distribution functions. The

  2. Total Absorption Gamma-ray Spectrometer (TAGS) Intensity Distributions from INL's Gamma-Ray Spectrometry Center

    DOE Data Explorer

    Greenwood, R. E.

    A 252Cf fission-product source and the INL on-line isotope separator were used to supply isotope-separated fission-product nuclides to a total absorption -ray spectrometer. This spectrometer consisted of a large (25.4-cm diameter x 30.5-cm long) NaI(Tl) detector with a 20.3-cm deep axial well in which is placed a 300-mm2 x 1.0-mm Si detector. The spectra from the NaI(Tl) detector are collected both in the singles mode and in coincidence with the B-events detected in the Si detector. Ideally, this detector would sum all the energy of the B- rays in each cascade following the population of daughter level by B- decay, so that the event could be directly associated with a particular daughter level. However, there are losses of energy from attenuation of the rays before they reach the detector, transmission of rays through the detector, escape of secondary photons from Compton scattering, escape of rays through the detector well, internal conversion, etc., and the measured spectra are thus more complicated than the ideal case and the analysis is more complex. Analysis methods have been developed to simulate all of these processes and thus provide a direct measure of the B- intensity distribution as a function of the excitation energy in the daughter nucleus. These data yield more accurate information on the B- distribution than conventional decay-scheme studies for complex decay schemes with large decay energies, because in the latter there are generally many unobserved and observed but unplaced rays. The TAGS data have been analyzed and published [R. E. Greenwood et al., Nucl Instr. and metho. A390(1997)] for 40 fission product-nuclides to determine the B- intensity distributions. [Copied from the TAGS page at http://www.inl.gov/gammaray/spectrometry/tags.shtml]. Those values are listed on this page for quick reference.

  3. The Interannual Stability of Cumulative Frequency Distributions for Convective System Size and Intensity

    NASA Technical Reports Server (NTRS)

    Mohr, Karen I.; Molinari, John; Thorncroft, Chris

    2009-01-01

    The characteristics of convective system populations in West Africa and the western Pacific tropical cyclone basin were analyzed to investigate whether interannual variability in convective activity in tropical continental and oceanic environments is driven by variations in the number of events during the wet season or by favoring large and/or intense convective systems. Convective systems were defined from Tropical Rainfall Measuring Mission (TRMM) data as a cluster of pixels with an 85-GHz polarization-corrected brightness temperature below 255 K and with an area of at least 64 square kilometers. The study database consisted of convective systems in West Africa from May to September 1998-2007, and in the western Pacific from May to November 1998-2007. Annual cumulative frequency distributions for system minimum brightness temperature and system area were constructed for both regions. For both regions, there were no statistically significant differences between the annual curves for system minimum brightness temperature. There were two groups of system area curves, split by the TRMM altitude boost in 2001. Within each set, there was no statistically significant interannual variability. Subsetting the database revealed some sensitivity in distribution shape to the size of the sampling area, the length of the sample period, and the climate zone. From a regional perspective, the stability of the cumulative frequency distributions implied that the probability that a convective system would attain a particular size or intensity does not change interannually. Variability in the number of convective events appeared to be more important in determining whether a year is either wetter or drier than normal.

  4. Atmosphere-Ocean Coupling Effect on Intense Tropical Cyclone Distribution and its Future Change with 60 km-AOGCM

    PubMed Central

    Ogata, Tomomichi; Mizuta, Ryo; Adachi, Yukimasa; Murakami, Hiroyuki; Ose, Tomoaki

    2016-01-01

    Atmosphere-ocean coupling effect on the frequency distribution of tropical cyclones (TCs) and its future change is studied using an atmosphere and ocean coupled general circulation model (AOGCM). In the present climate simulation, the atmosphere-ocean coupling in the AOGCM improves biases in the AGCM such as the poleward shift of the maximum of intense TC distribution in the Northern Hemisphere and too many intense TCs in the Southern Hemisphere. Particularly, subsurface cold water plays a key role to reduce these AGCM biases of intense TC distribution. Besides, the future change of intense TC distribution is significantly different between AOGCM and AGCM despite the same monthly SST. In the north Atlantic, subsurface warming causes larger increase in frequency of intense TCs in AOGCM than that in AGCM. Such subsurface warming in AOGCM also acts to alter large decrease of intense TC in AGCM to no significant change in AOGCM over the southwestern Indian Ocean. These results suggest that atmosphere-ocean coupling characterized by subsurface oceanic structure is responsible for more realistic intense TC distribution in the current climate simulation and gives significant impacts on its future projection. PMID:27418240

  5. Atmosphere-Ocean Coupling Effect on Intense Tropical Cyclone Distribution and its Future Change with 60 km-AOGCM

    NASA Astrophysics Data System (ADS)

    Ogata, Tomomichi; Mizuta, Ryo; Adachi, Yukimasa; Murakami, Hiroyuki; Ose, Tomoaki

    2016-07-01

    Atmosphere-ocean coupling effect on the frequency distribution of tropical cyclones (TCs) and its future change is studied using an atmosphere and ocean coupled general circulation model (AOGCM). In the present climate simulation, the atmosphere-ocean coupling in the AOGCM improves biases in the AGCM such as the poleward shift of the maximum of intense TC distribution in the Northern Hemisphere and too many intense TCs in the Southern Hemisphere. Particularly, subsurface cold water plays a key role to reduce these AGCM biases of intense TC distribution. Besides, the future change of intense TC distribution is significantly different between AOGCM and AGCM despite the same monthly SST. In the north Atlantic, subsurface warming causes larger increase in frequency of intense TCs in AOGCM than that in AGCM. Such subsurface warming in AOGCM also acts to alter large decrease of intense TC in AGCM to no significant change in AOGCM over the southwestern Indian Ocean. These results suggest that atmosphere-ocean coupling characterized by subsurface oceanic structure is responsible for more realistic intense TC distribution in the current climate simulation and gives significant impacts on its future projection.

  6. Atmosphere-Ocean Coupling Effect on Intense Tropical Cyclone Distribution and its Future Change with 60 km-AOGCM.

    PubMed

    Ogata, Tomomichi; Mizuta, Ryo; Adachi, Yukimasa; Murakami, Hiroyuki; Ose, Tomoaki

    2016-01-01

    Atmosphere-ocean coupling effect on the frequency distribution of tropical cyclones (TCs) and its future change is studied using an atmosphere and ocean coupled general circulation model (AOGCM). In the present climate simulation, the atmosphere-ocean coupling in the AOGCM improves biases in the AGCM such as the poleward shift of the maximum of intense TC distribution in the Northern Hemisphere and too many intense TCs in the Southern Hemisphere. Particularly, subsurface cold water plays a key role to reduce these AGCM biases of intense TC distribution. Besides, the future change of intense TC distribution is significantly different between AOGCM and AGCM despite the same monthly SST. In the north Atlantic, subsurface warming causes larger increase in frequency of intense TCs in AOGCM than that in AGCM. Such subsurface warming in AOGCM also acts to alter large decrease of intense TC in AGCM to no significant change in AOGCM over the southwestern Indian Ocean. These results suggest that atmosphere-ocean coupling characterized by subsurface oceanic structure is responsible for more realistic intense TC distribution in the current climate simulation and gives significant impacts on its future projection. PMID:27418240

  7. The Intensity Distribution of Faint Gamma-Ray Bursts Detected with BATSE

    NASA Technical Reports Server (NTRS)

    Kommers, Jefferson M.; Lewin, Walter H. G.; Kouveliotou, Chryssa; VanParadijs, Jan; Pendleton, Geoffrey N.; Meegan, Charles A.; Fishman, Gerald J.

    2000-01-01

    We have recently completed a search of 6 years of archival BATSE data for gamma-ray bursts (GRBS) that were too faint to activate the real-time burst detection system running on board the spacecraft. These "nontriggered" bursts can be combined with the "triggered" bursts detected on board to produce a GRB intensity distribution that reaches peak fluxes a factor of approximately 2 lower than could be studied previously. The value of the statistic (in Euclidean space) for the bursts we detect is 0.177 plus or minus 0.006. This surprisingly low value is obtained because we detected very few bursts on the 4.096 s and 8.192 s timescales (where most bursts have their highest signal-to-noise ratio) that were not already detected on the 1.024 s timescale. If allowance is made for a power-law distribution of intrinsic peak luminosities, the extended peak flux distribution is consistent with models in which the redshift distribution of the gamma-ray burst rate approximately traces the star formation history of the universe. We argue that this class of models is preferred over those in which the burst rate is independent of redshift. We use the peak flux distribution to derive a limit of 10% (99% confidence) on the fraction of the total burst rate that could be contributed by a spatially homogeneous (in Euclidean space) subpopulation of burst sources, such as type lb/c supernovae. These results lend support to the conclusions of previous studies predicting that relatively few faint "classical" GRBs will be found below the BATSE onboard detection threshold.

  8. "Caught in the Continuum"

    ERIC Educational Resources Information Center

    Nisbet, Jan

    2004-01-01

    This article presents a critical review of Steve Taylor's Caught in the Continuum. Steve Taylor describes the flawed thinking associated with the "least restrictive environment" (LRE) principle and the related continuum model of human services that linked severity of disability with segregation, and required improvements in skills as a…

  9. The star formation rate intensity distribution function—. Comparison of observations with hierarchical galaxy formation

    NASA Astrophysics Data System (ADS)

    Barkana, Rennan

    2002-09-01

    Recently, Lanzetta et al. [ApJ (2002) in press] have measured the distribution of star formation rate intensity in galaxies at various redshifts. This data set has a number of advantages relative to galaxy luminosity functions; the effect of surface-brightness dimming on the selection function is simpler to understand, and this data set also probes the size distribution of galactic disks. We predict this function using semi-analytic models of hierarchical galaxy formation in a ΛCDM cosmology. We show that the basic trends found in the data follow naturally from the redshift evolution of dark matter halos. The data are consistent with a constant efficiency of turning gas into stars in galaxies, with a best-fit value of 2%, where dust obscuration is neglected; equivalently, the data are consistent with a cosmic star formation rate which is constant to within a factor of two at all redshifts above two. However, the practical ability to use this kind of distribution to measure the total cosmic star formation rate is limited by the predicted shape of an approximate power law with a smoothly varying power, without a sharp break.

  10. Angular intensity distribution of a molecular oxygen beam scattered from a graphite surface.

    PubMed

    Oh, Junepyo; Kondo, Takahiro; Arakawa, Keitaro; Saito, Yoshihiko; Hayes, W W; Manson, J R; Nakamura, Junji

    2011-06-30

    The scattering of the oxygen molecule from a graphite surface has been studied using a molecular beam scattering technique. The angular intensity distributions of scattered oxygen molecules were measured at incident energies from 291 to 614 meV with surface temperatures from 150 to 500 K. Every observed distribution has a single peak at a larger final angle than the specular angle of 45° which indicates that the normal component of the translation energy of the oxygen molecule is lost by the collision with the graphite surface. The amount of the energy loss by the collision has been roughly estimated as about 30-41% based on the assumption of the tangential momentum conservation during the collision. The distributions have also been analyzed with two theoretical models, the hard cubes model and the smooth surface model. These results indicate that the scattering is dominated by a single collision event of the particle with a flat surface having a large effective mass. The derived effective mass of the graphite surface for the incoming oxygen is 9-12 times heavier than that of a single carbon atom, suggesting a large cooperative motion of the carbon atoms in the topmost graphene layer. PMID:21446680

  11. Periodic amplitude variations in Jovian continuum radiation

    NASA Astrophysics Data System (ADS)

    Kurth, W. S.; Gurnett, D. A.; Scarf, F. L.

    1986-12-01

    An analysis of periodic variations in the amplitude of continuum radiation near 3 kHz trapped in the Jovian magnetosphere shows structure with periods near both 5 and 10 horus. Contrary to a plausible initial idea, the continuum amplitudes are not organized by the position of the observer relative to the dense plasma sheet. Instead, there seem to be perferred orientations of system III longitude with respect to the direction to the sun which account for the peaks. This implies a clocklike modulation of the continuum radiation intensity as opposed to a searchlight effect. The importance of the dipole longitude solar wind alignment to the amplitude of the continuum radiation implies that the source region of the radiation is near the magnetopause and may indirectly tie the generation of the radio waves to the clocklike modulation of energetic electron fluxes from Jupiter.

  12. Numerical model for light propagation and light intensity distribution inside coated fused silica capillaries

    NASA Astrophysics Data System (ADS)

    Piasecki, Tomasz; Macka, Mirek; Paull, Brett; Brabazon, Dermot

    2011-07-01

    Numerical simulations of light propagation through capillaries have been reported to a limited extent in the literature for uses such as flow-cell design. These have been restricted to prediction of light path for very specific cases to date. In this paper, a new numerical model of light propagation through multi-walled cylindrical systems, to represent coated and uncoated capillaries is presented. This model allows for light ray paths and light intensity distribution within the capillary to be predicted. Macro-scale (using PMMA and PC cylinders) and micro-scale (using PTFE coated fused silica capillaries) experiments were conducted to validate the model's accuracy. These experimental validations have shown encouragingly good agreement between theoretical predictions and measured results, which could allow for optimisation of associated regions for monolith synthesis and use in fluidic chromatography, optical detection systems and flow cells for capillary electrophoresis and flow injection analysis.

  13. Distribution of temperature elevation caused by moving high-intensity focused ultrasound transducer

    NASA Astrophysics Data System (ADS)

    Kim, Jungsoon; Jung, Jihee; Kim, Moojoon; Ha, Kanglyeol; Lee, Eunghwa; Lee, Ilkwon

    2015-07-01

    Ultrasonic thermal treatment for dermatology has been developed using a small high-intensity focused ultrasound (HIFU) transducer. The transducer moves horizontally at a constant while it emits focused ultrasound because the treatment needs a high-temperature area in skin tissue over a wide range of depths. In this paper, a tissue-mimicking phantom made of carrageenan and a thermochromic film were adopted to examine the temperature distribution in the phantom noninvasively when the focused ultrasound was irradiated from the moving transducer. The dependence of the high-temperature area on the irradiated acoustic energy and on the movement interval of the HIFU was analyzed experimentally. The results will be useful in ensuring safety and estimating the remedial value of the treatment.

  14. Hydrogen Balmer alpha intensity distributions and line profiles from multiple scattering theory using realistic geocoronal models

    NASA Technical Reports Server (NTRS)

    Anderson, D. E., Jr.; Meier, R. R.; Hodges, R. R., Jr.; Tinsley, B. A.

    1987-01-01

    The H Balmer alpha nightglow is investigated by using Monte Carlo models of asymmetric geocoronal atomic hydrogen distributions as input to a radiative transfer model of solar Lyman-beta radiation in the thermosphere and atmosphere. It is shown that it is essential to include multiple scattering of Lyman-beta radiation in the interpretation of Balmer alpha airglow data. Observations of diurnal variation in the Balmer alpha airglow showing slightly greater intensities in the morning relative to evening are consistent with theory. No evidence is found for anything other than a single sinusoidal diurnal variation of exobase density. Dramatic changes in effective temperature derived from the observed Balmer alpha line profiles are expected on the basis of changing illumination conditions in the thermosphere and exosphere as different regions of the sky are scanned.

  15. A Distributed Network for Intensive Longitudinal Monitoring in Metastatic Triple-Negative Breast Cancer

    PubMed Central

    Blau, C. Anthony; Ramirez, Arturo B.; Blau, Sibel; Pritchard, Colin C.; Dorschner, Michael O.; Schmechel, Stephen C.; Martins, Timothy J.; Mahen, Elisabeth M.; Burton, Kimberly A.; Komashko, Vitalina M.; Radenbaugh, Amie J.; Dougherty, Katy; Thomas, Anju; Miller, Christopher P.; Annis, James; Fromm, Jonathan R.; Song, Chaozhong; Chang, Elizabeth; Howard, Kellie; Austin, Sharon; Schmidt, Rodney A.; Linenberger, Michael L.; Becker, Pamela S.; Senecal, Francis M.; Mecham, Brigham H.; Lee, Su-In; Madan, Anup; Ronen, Roy; Dutkowski, Janusz; Heimfeld, Shelly; Wood, Brent L.; Stilwell, Jackie L.; Kaldjian, Eric P.; Haussler, David; Zhu, Jingchun

    2016-01-01

    Accelerating cancer research is expected to require new types of clinical trials. This report describes the Intensive Trial of OMics in Cancer (ITOMIC) and a participant with triple-negative breast cancer metastatic to bone, who had markedly elevated circulating tumor cells (CTCs) that were monitored 48 times over 9 months. A total of 32 researchers from 14 institutions were engaged in the patient’s evaluation; 20 researchers had no prior involvement in patient care and 18 were recruited specifically for this patient. Whole-exome sequencing of 3 bone marrow samples demonstrated a novel ROS1 variant that was estimated to be present in most or all tumor cells. After an initial response to cisplatin, a hypothesis of crizotinib sensitivity was disproven. Leukapheresis followed by partial CTC enrichment allowed for the development of a differential high-throughput drug screen and demonstrated sensitivity to investigational BH3-mimetic inhibitors of BCL-2 that could not be tested in the patient because requests to the pharmaceutical sponsors were denied. The number and size of CTC clusters correlated with clinical status and eventually death. Focusing the expertise of a distributed network of investigators on an intensively monitored patient with cancer can generate high-resolution views of the natural history of cancer and suggest new opportunities for therapy. Optimization requires access to investigational drugs. PMID:26733551

  16. A Distributed Network for Intensive Longitudinal Monitoring in Metastatic Triple-Negative Breast Cancer.

    PubMed

    Blau, C Anthony; Ramirez, Arturo B; Blau, Sibel; Pritchard, Colin C; Dorschner, Michael O; Schmechel, Stephen C; Martins, Timothy J; Mahen, Elisabeth M; Burton, Kimberly A; Komashko, Vitalina M; Radenbaugh, Amie J; Dougherty, Katy; Thomas, Anju; Miller, Christopher P; Annis, James; Fromm, Jonathan R; Song, Chaozhong; Chang, Elizabeth; Howard, Kellie; Austin, Sharon; Schmidt, Rodney A; Linenberger, Michael L; Becker, Pamela S; Senecal, Francis M; Mecham, Brigham H; Lee, Su-In; Madan, Anup; Ronen, Roy; Dutkowski, Janusz; Heimfeld, Shelly; Wood, Brent L; Stilwell, Jackie L; Kaldjian, Eric P; Haussler, David; Zhu, Jingchun

    2016-01-01

    Accelerating cancer research is expected to require new types of clinical trials. This report describes the Intensive Trial of OMics in Cancer (ITOMIC) and a participant with triple-negative breast cancer metastatic to bone, who had markedly elevated circulating tumor cells (CTCs) that were monitored 48 times over 9 months. A total of 32 researchers from 14 institutions were engaged in the patient's evaluation; 20 researchers had no prior involvement in patient care and 18 were recruited specifically for this patient. Whole-exome sequencing of 3 bone marrow samples demonstrated a novel ROS1 variant that was estimated to be present in most or all tumor cells. After an initial response to cisplatin, a hypothesis of crizotinib sensitivity was disproven. Leukapheresis followed by partial CTC enrichment allowed for the development of a differential high-throughput drug screen and demonstrated sensitivity to investigational BH3-mimetic inhibitors of BCL-2 that could not be tested in the patient because requests to the pharmaceutical sponsors were denied. The number and size of CTC clusters correlated with clinical status and eventually death. Focusing the expertise of a distributed network of investigators on an intensively monitored patient with cancer can generate high-resolution views of the natural history of cancer and suggest new opportunities for therapy. Optimization requires access to investigational drugs. PMID:26733551

  17. Universally-composable finite-key analysis for efficient four-intensity decoy-state quantum key distribution

    NASA Astrophysics Data System (ADS)

    Jiang, Haodong; Gao, Ming; Yan, Bao; Wang, Weilong; Ma, Zhi

    2016-04-01

    We propose an efficient four-intensity decoy-state BB84 protocol and derive concise security bounds for this protocol with the universally composable finite-key analysis method. Comparing with the efficient three-intensity protocol, we find that our efficient four-intensity protocol can increase the secret key rate by at least 30%. Particularly, this increasing rate of secret key rate will be raised as the transmission distance increases. At a large transmission distance, our efficient four-intensity protocol can improve the performance of quantum key distribution profoundly.

  18. Predicting Distribution and Inter-Annual Variability of Tropical Cyclone Intensity from a Stochastic, Multiple-Linear Regression Model

    NASA Astrophysics Data System (ADS)

    Lee, C. Y.; Tippett, M. K.; Sobel, A. H.; Camargo, S. J.

    2014-12-01

    We are working towards the development of a new statistical-dynamical downscaling system to study the influence of climate on tropical cyclones (TCs). The first step is development of an appropriate model for TC intensity as a function of environmental variables. We approach this issue with a stochastic model consisting of a multiple linear regression model (MLR) for 12-hour intensity forecasts as a deterministic component, and a random error generator as a stochastic component. Similar to the operational Statistical Hurricane Intensity Prediction Scheme (SHIPS), MLR relates the surrounding environment to storm intensity, but with only essential predictors calculated from monthly-mean NCEP reanalysis fields (potential intensity, shear, etc.) and from persistence. The deterministic MLR is developed with data from 1981-1999 and tested with data from 2000-2012 for the Atlantic, Eastern North Pacific, Western North Pacific, Indian Ocean, and Southern Hemisphere basins. While the global MLR's skill is comparable to that of the operational statistical models (e.g., SHIPS), the distribution of the predicted maximum intensity from deterministic results has a systematic low bias compared to observations; the deterministic MLR creates almost no storms with intensities greater than 100 kt. The deterministic MLR can be significantly improved by adding the stochastic component, based on the distribution of random forecasting errors from the deterministic model compared to the training data. This stochastic component may be thought of as representing the component of TC intensification that is not linearly related to the environmental variables. We find that in order for the stochastic model to accurately capture the observed distribution of maximum storm intensities, the stochastic component must be auto-correlated across 12-hour time steps. This presentation also includes a detailed discussion of the distributions of other TC-intensity related quantities, as well as the inter

  19. Generation of Initial Kinetic Distributions for Simulation of Long-Pulse Charged Particle Beams with High Space-Charge intensity

    SciTech Connect

    Lund, Steven M.; Kikuchi, Takashi; Davidson, Ronald C.

    2007-04-03

    Self-consistent Vlasov-Poisson simulations of beams with high space-charge intensity often require specification of initial phase-space distributions that reflect properties of a beam that is well adapted to the transport channel--both in terms of low-order rms (envelope) properties as well as the higher-order phase-space structure. Here, we first review broad classes of kinetic distributions commonly in use as initial Vlasov distributions in simulations of unbunched or weakly bunched beams with intense space-charge fields including: the Kapchinskij-Vladimirskij (KV) equilibrium, continuous-focusing equilibria with specific detailed examples, and various non-equilibrium distributions, such as the semi-Gaussian distribution and distributions formed from specified functions of linear-field Courant-Snyder invariants. Important practical details necessary to specify these distributions in terms of usual accelerator inputs are presented in a unified format. Building on this presentation, a new class of approximate initial kinetic distributions are constructed using transformations that preserve linear-focusing single-particle Courant-Snyder invariants to map initial continuous-focusing equilibrium distributions to a form more appropriate for non-continuous focusing channels. Self-consistent particle-in-cell simulations are employed to show that the approximate initial distributions generated in this manner are better adapted to the focusing channels for beams with high space-charge intensity. This improved capability enables simulation applications that more precisely probe intrinsic stability properties and machine performance.

  20. Generation of initial Vlasov distributions for simulation of charged particle beams with high space-charge intensity

    SciTech Connect

    Lund, S M; Kikuchi, T; Davidson, R C

    2007-04-12

    Self-consistent Vlasov simulations of beams with high space-charge intensity often require specification of initial phase-space distributions that reflect properties of a beam that is well adapted to the transport channel, both in terms of low-order rms (envelope) properties as well as the higher-order phase-space structure. Here, we first review broad classes of distributions commonly in use as initial Vlasov distributions in simulations of beams with intense space-charge fields including: the Kapchinskij-Vladimirskij (KV) equilibrium, continuous-focusing equilibria with specific detailed examples, and various non-equilibrium distributions, such as the semi-Gaussian distribution and distributions formed from specified functions of linear-field Courant-Snyder invariants. Important practical details necessary to specify these distributions in terms of usual accelerator inputs are presented in a unified format. Building on this presentation, a new class of approximate initial distributions are constructed using transformations that preserve linear-focusing single-particle Courant-Snyder invariants to map initial continuous-focusing equilibrium distributions to a form more appropriate for non-continuous focusing channels. Self-consistent particle-in-cell simulations are employed to show that the approximate initial distributions generated in this manner are better adapted to the focusing channels for beams with high space-charge intensity. This improved capability enables simulation applications that more precisely probe intrinsic stability properties and machine performance.

  1. Tsunami source parameters estimated from slip distribution and their relation to tsunami intensity

    NASA Astrophysics Data System (ADS)

    Bolshakova, Anna; Nosov, Mikhail; Kolesov, Sergey

    2015-04-01

    Estimation of the level of tsunami hazard on the basis of earthquake moment magnitude often fails. The most important reason for this is that tsunamis are related to earthquakes in a complex and ambiguous way. In order to reveal a measure of tsunamigenic potential of an earthquake that would be better than moment magnitude of earthquake we introduce a set of tsunami source parameters that can be calculated from co-seismic ocean-bottom deformation and bathymetry. We consider more than two hundred ocean-bottom earthquakes (1923-2014) those for which detailed slip distribution data (Finite Fault Model) are available on USGS, UCSB, Caltech, and eQuake-RC sites. Making use of the Okada formulae the vector fields of co-seismic deformation of ocean bottom are estimated from the slip distribution data. Taking into account bathymetry (GEBCO_08) we determine tsunami source parameters such as double amplitude of bottom deformation, displaced water volume, potential energy of initial elevation, etc. The tsunami source parameters are examined as a function of earthquake moment magnitude. The contribution of horisontal component of ocean bottom deformation to tsunami generation is investigated. We analyse the Soloviev-Imamura tsunami intensity as a function of tsunami source parameters. The possibility of usage of tsunami source parameters instead of moment magnitude in tsunami warning is discussed. This work was supported by the Russian Foundation for Basic Research, project 14-05-31295

  2. Electron-momentum distributions and photoelectron spectra of atoms driven by an intense spatially inhomogeneous field

    NASA Astrophysics Data System (ADS)

    Ciappina, M. F.; Pérez-Hernández, J. A.; Shaaran, T.; Roso, L.; Lewenstein, M.

    2013-06-01

    We use the three-dimensional time-dependent Schrödinger equation (3 D-TDSE) to calculate angular electron momentum distributions and photoelectron spectra of atoms driven by spatially inhomogeneous fields. An example for such inhomogeneous fields is the locally enhanced field induced by resonant plasmons, appearing at surfaces of metallic nanoparticles, nanotips, and gold bow-tie shaped nanostructures. Our studies show that the inhomogeneity of the laser electric field plays an important role on the above-threshold ionization process in the tunneling regime, causing significant modifications on the electron momentum distributions and photoelectron spectra, while its effects in the multiphoton regime appear to be negligible. Indeed, through the tunneling above-threshold ionization (ATI) process, one can obtain higher energy electrons as well as a high degree of asymmetry in the momentum space map. In this study we consider near infrared laser fields with intensities in the mid- 1014 W/cm2 range and we use a linear approximation to describe their spatial dependence. We show that in this case it is possible to drive electrons with energies in the near-keV regime. Furthermore, we study how the carrier envelope phase influences the emission of ATI photoelectrons for few-cycle pulses. Our quantum mechanical calculations are fully supported by their classical counterparts.

  3. Spatial Intensity Distribution Analysis Reveals Abnormal Oligomerization of Proteins in Single Cells.

    PubMed

    Godin, Antoine G; Rappaz, Benjamin; Potvin-Trottier, Laurent; Kennedy, Timothy E; De Koninck, Yves; Wiseman, Paul W

    2015-08-18

    Knowledge of membrane receptor organization is essential for understanding the initial steps in cell signaling and trafficking mechanisms, but quantitative analysis of receptor interactions at the single-cell level and in different cellular compartments has remained highly challenging. To achieve this, we apply a quantitative image analysis technique-spatial intensity distribution analysis (SpIDA)-that can measure fluorescent particle concentrations and oligomerization states within different subcellular compartments in live cells. An important technical challenge faced by fluorescence microscopy-based measurement of oligomerization is the fidelity of receptor labeling. In practice, imperfect labeling biases the distribution of oligomeric states measured within an aggregated system. We extend SpIDA to enable analysis of high-order oligomers from fluorescence microscopy images, by including a probability weighted correction algorithm for nonemitting labels. We demonstrated that this fraction of nonemitting probes could be estimated in single cells using SpIDA measurements on model systems with known oligomerization state. Previously, this artifact was measured using single-step photobleaching. This approach was validated using computer-simulated data and the imperfect labeling was quantified in cells with ion channels of known oligomer subunit count. It was then applied to quantify the oligomerization states in different cell compartments of the proteolipid protein (PLP) expressed in COS-7 cells. Expression of a mutant PLP linked to impaired trafficking resulted in the detection of PLP tetramers that persist in the endoplasmic reticulum, while no difference was measured at the membrane between the distributions of wild-type and mutated PLPs. Our results demonstrate that SpIDA allows measurement of protein oligomerization in different compartments of intact cells, even when fractional mislabeling occurs as well as photobleaching during the imaging process, and

  4. Assessment the Trend of Inequality in the Distribution of Intensive Care Beds in Iran: Using GINI Index

    PubMed Central

    Meskarpour-Amiri, Mohammad; Mehdizadeh, Parisa; Barouni, Mohsen; Dopeykar, Nooredin; Ramezanian, Maryam

    2014-01-01

    Background and Aim: While most of the published researches have reported the amount of inequity in geographical distribution of important health resources, only a small number of studies have focused on the trend of inequality in the distribution of these resources. The purpose of this study was to determine the trend of inequality in the distribution of intensive care beds in Iran during 2010 to 2012 by using the Gini coefficient. Methods: This is a cross-sectional research conducted in 2013. The changes over three years (2010 to 2012) were calculated by Gini coefficient to investigate the trend of inequality in geographical distribution of intensive care beds (CCU, ICU and NICU). Results: The Gini coefficient for CCU beds was calculated as 0.02, 0.04 and 0.06 in 2010, 2011 and 2012, respectively. The Gini coefficient for ICU beds was calculated as 0.03, 0.05 and 0.05 in 2010, 2011 and 2012, respectively. Also, the Gini coefficient for NICU bed was calculated as 0.02, 0.03 and 0.04 in 2010, 2011 and 2012, respectively. Conclusion: Regarding to Gini coefficient, the trend of inequality was increased in the distribution of intensive care beds in Iran. Particularly, the inequalities in distribution of CCU beds were significantly increased during past years. In fact, if this trend of inequality continues, the distribution of intensive care beds will be extremely unequal in the next five years in Iran. PMID:25363104

  5. Kernel Continuum Regression.

    PubMed

    Lee, Myung Hee; Liu, Yufeng

    2013-12-01

    The continuum regression technique provides an appealing regression framework connecting ordinary least squares, partial least squares and principal component regression in one family. It offers some insight on the underlying regression model for a given application. Moreover, it helps to provide deep understanding of various regression techniques. Despite the useful framework, however, the current development on continuum regression is only for linear regression. In many applications, nonlinear regression is necessary. The extension of continuum regression from linear models to nonlinear models using kernel learning is considered. The proposed kernel continuum regression technique is quite general and can handle very flexible regression model estimation. An efficient algorithm is developed for fast implementation. Numerical examples have demonstrated the usefulness of the proposed technique. PMID:24058224

  6. Modeling the neutral hydrogen distribution in the post-reionization Universe: intensity mapping

    SciTech Connect

    Villaescusa-Navarro, Francisco; Viel, Matteo; Datta, Kanan K.; Choudhury, T. Roy E-mail: viel@oats.inaf.it E-mail: tirth@ncra.tifr.res.in

    2014-09-01

    We model the distribution of neutral hydrogen (HI) in the post-reionization era and investigate its detectability in 21 cm intensity mapping with future radio telescopes like the Square Kilometer array (SKA). We rely on high resolution hydrodynamical N-body simulations that have a state-of-the-art treatment of the low density photoionized gas in the inter-galactic medium (IGM). The HI is assigned a-posteriori to the gas particles following two different approaches: a halo-based method in which HI is assigned only to gas particles residing within dark matter halos; a particle-based method that assigns HI to all gas particles using a prescription based on the physical properties of the particles. The HI statistical properties are then compared to the observational properties of Damped Lyman-α Absorbers (DLAs) and of lower column density systems and reasonable good agreement is found for all the cases. Among the halo-based method, we further consider two different schemes that aim at reproducing the observed properties of DLAs by distributing HI inside halos: one of this results in a much higher bias for DLAs, in agreement with recent observations, which boosts the 21 cm power spectrum by a factor ∼ 4 with respect to the other recipe. Furthermore, we quantify the contribution of HI in the diffuse IGM to both Ω{sub HI} and the HI power spectrum finding to be subdominant in both cases. We compute the 21 cm power spectrum from the simulated HI distribution and calculate the expected signal for both SKA1-mid and SKA1-low configurations at 2.4 ≤ z ≤ 4. We find that SKA will be able to detect the 21 cm power spectrum, in the non-linear regime, up to k ∼ 1 h/Mpc for SKA1-mid and k ∼ 5 h/Mpc for SKA1-low with 100 hours of observations. We also investigate the perspective of imaging the HI distribution. Our findings indicate that SKA1-low could detect the most massive HI peaks with a signal to noise ratio (SNR) higher than 5 for an observation time of about 1000

  7. Statistical distribution of the optical intensity obtained using a Gaussian Schell model for space-to-ground link laser communications

    NASA Astrophysics Data System (ADS)

    Li, Mengnan; Tan, Liying; Ma, Jing; Yu, Siyuan; Yang, Qingbo; Wu, Jiajie

    2016-05-01

    Based on the characteristics of the laser device and the inevitable error of the processing technique, a laser beam emitted from a communication terminal can be represented by the Gaussian Schell model (GSM). In space-to-ground link laser communications, the optical intensity is affected by the source coherence parameter and the zenith angle. With full consideration of these two parameters, the statistical distribution model of the optical intensity with a GSM laser in both downlink and uplink is derived. The simulation results indicate that increasing the source coherence parameter has an effect on the statistical distribution of the optical intensity; this effect is highly similar to the effect of a larger zenith angle. The optical intensity invariably degrades with increasing source coherence parameter or zenith angle. The results of this work can promote the improvement of the redundancy design of a laser communication receiver system.

  8. A distributed model for slope stability analysis using radar detected rainfall intensity

    NASA Astrophysics Data System (ADS)

    Leoni, L.; Rossi, G.; Catani, F.

    2009-04-01

    The term shallow landslides is widely used in literature to describe a slope movement of limited size that mainly develops in soils up to a maximum of a few meters. Shallow landslides are usually triggered by heavy rainfall because, as the water starts to infiltrate in the soil, the pore-water pressure increases so that the shear strength of the soil is reduced leading to slope failure. We have developed a distributed hydrological-geotechnical model for the forecasting of the temporal and spatial distribution of shallow landslides to be used as a warning system for civil protection purpose. The model uses radar detected rainfall intensity as the input for the hydrological simulation of the infiltration. Using the rainfall pattern detected by the radar is in fact possible to dynamically control the redistribution of groundwater pressure associated with transient infiltration of rain so as to infer the slope stability of the studied area. The model deals with both saturated and unsaturated conditions taking into account the effect of soil suction when the soil is not completely saturated. Two pilot sites have been chosen to develop and test this model: the Armea basin (Liguria, Italy) and the Ischia Island (Campania, Italy). In recent years several severe rainstorms have occurred in both these areas. In at least two cases these have triggered numerous shallow landslides that have caused victims and damaged roads, buildings and agricultural activities. In its current stage, the basic basin-scale model applied for predicting the probable location of shallow landslides involves several stand-alone components. The solution suggested by Iverson for the Richards equation is used to estimate the transient groundwater pressure head distribution according to radar detected rainfall intensity. A soil depth prediction scheme and a limit-equilibrium infinite slope stability algorithm are used to calculate the distributed factor of safety (FS) at different depths and to record

  9. The tracking performance of distributed recoverable flight control systems subject to high intensity radiated fields

    NASA Astrophysics Data System (ADS)

    Wang, Rui

    It is known that high intensity radiated fields (HIRF) can produce upsets in digital electronics, and thereby degrade the performance of digital flight control systems. Such upsets, either from natural or man-made sources, can change data values on digital buses and memory and affect CPU instruction execution. HIRF environments are also known to trigger common-mode faults, affecting nearly-simultaneously multiple fault containment regions, and hence reducing the benefits of n-modular redundancy and other fault-tolerant computing techniques. Thus, it is important to develop models which describe the integration of the embedded digital system, where the control law is implemented, as well as the dynamics of the closed-loop system. In this dissertation, theoretical tools are presented to analyze the relationship between the design choices for a class of distributed recoverable computing platforms and the tracking performance degradation of a digital flight control system implemented on such a platform while operating in a HIRF environment. Specifically, a tractable hybrid performance model is developed for a digital flight control system implemented on a computing platform inspired largely by the NASA family of fault-tolerant, reconfigurable computer architectures known as SPIDER (scalable processor-independent design for enhanced reliability). The focus will be on the SPIDER implementation, which uses the computer communication system known as ROBUS-2 (reliable optical bus). A physical HIRF experiment was conducted at the NASA Langley Research Center in order to validate the theoretical tracking performance degradation predictions for a distributed Boeing 747 flight control system subject to a HIRF environment. An extrapolation of these results for scenarios that could not be physically tested is also presented.

  10. Real Distribution of the Coronal Green Line Intensity and Modelling Study of Galactic Cosmic Ray Propagation

    NASA Astrophysics Data System (ADS)

    Gushchina, R. T.; Alania, M. V.; Gil, A.; Iskra, K.; Siluszyk, M.

    2003-07-01

    transport equation of galactic cosmic rays (GCR) has been numerically solved for different qA>0 (1996) and qA<0 (1987) epochs assuming that free path of GCR scattering in the interplanetary space is controlled by the Sun's coronal green line intensity (CGLI). We found some distinctions in the distribution of the expected heliolatitudinal gradients of GCR for two and three dimensional interplanetary magnetic field. INTRODUCTION. modulation of GCR in the interplanetary space is generally determined by four processesdiffusion, convection, drift and energy change of GCR particles due to interaction with the solar wind. The joint effect of all above mentioned processes result the 11year variation of GCR. In papers [1-3] are assumed that the general reason of the 11-year variation of GCR in the energy range more than 1 GeV is different structure of the irregularities of the IMF in the maxima and minima epochs of solar activity (SA) caused the radical changes of the dependence of diffusion coefficient on the rigidity of GCR particles. EXPERIMENTAL DATA AND METHOD OF INVESTIGATION. experimental data of sunspot numbers, sunspots' areas and CGLI (λ = 5303˚) show a considerable changes during the 11-year cycle of SA, while e.g. A the changes of the solar wind velocity are not so noticeable [4, 5]. An attempt to take into account influences of the real distributions of the sunspot's areas and the Sun's CGLI on the modulation of GCR considering delay time of the phenomena in the interplanetary space with respect to the processes on the Sun have been undertaken in papers [6-8]. One of parameters of SA contentiously observed on the Earth is the Sun's CGLI. One can suppose that a modulation of GCR by some means is controlled by the changes of the CGLI; particularly there is assumed that a scattering free path of GCR transport is related with the

  11. Characterization and control of peak intensity distribution at the focus of a spatiotemporally focused femtosecond laser beam.

    PubMed

    He, Fei; Zeng, Bin; Chu, Wei; Ni, Jielei; Sugioka, Koji; Cheng, Ya; Durfee, Charles G

    2014-04-21

    We report on experimental examination of two-photon fluorescence excitation (TPFE) at the focus of a spatially chirped femtosecond laser beam, which reveals an unexpected tilted peak intensity distribution in the focal spot. Our theoretical calculation shows that the tilting of the peak intensity distribution originates from the fact that along the optical axis of objective lens, the spatiotemporally focused pulse reaches its shortest duration exactly at the focal plane. However, when moving away from the optical axis along the direction of spatial chirp of the incident pulse, the pulse reaches its shortest duration either before or after the focal plane, depending on whether the pulse duration is measured above or below the optical axis as well as the sign of the spatial chirp. The tilting of the peak intensity distribution in the focal spot of the spatiotemporally focused femtosecond laser beam can play important roles in applications such as femtosecond laser micromachining and bio-imaging. PMID:24787858

  12. Intensity distribution of Fizeau fringes in transmission with the real path of the interfered multiple-beams

    NASA Astrophysics Data System (ADS)

    Ramadan, W. A.

    2014-07-01

    In this paper, a theory is presented to estimate the intensity distribution of Fizeau fringes in transmission. In this theory the real path of the interfered light beams, through the wedge interferometer, has been considered. Interference of multiple beams has been estimated up to 12 beams considering the phase and amplitude for each beam. The summation of these waves has been done using the vector summation theory. The numerical construction of Fizeau fringes in space has been calculated considering the superposition of different number of beams. The influence of the wedge angle, number of the interfered beams and the wedge gap on the intensity distribution has been investigated. The most interesting observation in this study is the intensity distribution in different planes above the interferometer in both calculated and experimental Fizeau fringes using a He-Ne laser. Some experimental interferograms have been illustrated to confirm the validity of the proposed theory.

  13. OBSERVATION OF THE FAR-ULTRAVIOLET CONTINUUM BACKGROUND WITH SPEAR/FIMS

    SciTech Connect

    Seon, Kwang-Il; Han, Wonyong; Shinn, Jongho; Kim, Il-Joong; Edelstein, Jerry; Korpela, Eric; Witt, Adolf; Min, Kyoung-Wook; Park, Jae-Woo

    2011-10-01

    We present the general properties of the far-ultraviolet (FUV; 1370-1710 A) continuum background over most of the sky, obtained with the Spectroscopy of Plasma Evolution from Astrophysical Radiation (SPEAR) instrument (also known as FIMS), flown aboard the STSAT-1 satellite mission. We find that the diffuse FUV continuum intensity is well correlated with N{sub HI}, 100 {mu}m, and H{alpha} intensities but anti-correlated with soft X-ray intensity. The correlation of the diffuse background with the direct stellar flux is weaker than the correlation with other parameters. The continuum spectra are relatively flat. However, a weak softening of the FUV spectra toward some sight lines, mostly at high Galactic latitudes, is found not only in direct stellar but also in diffuse background spectra. The diffuse background is relatively softer than the direct stellar spectrum. We also find that the diffuse FUV background averaged over the sky has a bit softer spectrum compared to direct stellar radiation. A map of the ratio of 1370-1520 A to 1560-1710 A band intensity shows that the sky is divided into roughly two parts. However, this map shows a lot of patchy structures on small scales. The spatial variation of the hardness ratio seems to be largely determined by the longitudinal distribution of OB-type stars in the Galactic plane. A correlation of the hardness ratio with the FUV intensity is found at high intensities but an anti-correlation is found at low intensities. We also find evidence that the FUV intensity distribution is log-normal in nature.

  14. Solar Intensity Distributing and Convolving Optic (SIDCO) Concept for the CLARREO Reflected Solar Imaging Spectrometer (RSIS)

    NASA Astrophysics Data System (ADS)

    Matthews, G.; Itt Geospatial Systems Climate Calibration Group

    2010-12-01

    The CLARREO mission has outlined some preliminary requirements for a space based spectrometer to measure visible to near infra-red Earth albedo with a 0.3% absolute accuracy, 0.1%/decade calibration stability and a 10km footprint size at nadir. It is well known that some Earth viewing optics undergo significant degradation at solar wavelengths when in orbit which is not directly detectable using onboard calibration sources. This makes the requirements for CLARREO very challenging, requiring the development of new instrumental concepts in order to meet the goals required. A new type of telescope system is hence proposed that uses raster scan data from the Sun as its primary calibration metric. The 10-5 attenuation necessary for Earth viewing optics to view the Sun directly is achieved using the new concept of a Solar Intensity Distributing and Convolving Optic (SIDCO), whose degradation itself is monitored to very high accuracy and precision. The proposed instrument requires no more moving parts or gimbals than those used on the long running CERES instruments. It also provides redundancy in order to continue benchmark albedo measurements even during the instruments solar calibration periods. Such redundancy also allows continual monitoring of the incoming solar spectrum.

  15. Characterization of the fast electrons distribution produced in a high intensity laser target interaction

    NASA Astrophysics Data System (ADS)

    Westover, B.; Chen, C. D.; Patel, P. K.; McLean, H.; Beg, F. N.

    2014-03-01

    Experiments on the Titan laser (˜150 J, 0.7 ps, 2 × 1020 W cm-2) at the Lawrence Livermore National Laboratory were carried out in order to study the properties of fast electrons produced by high-intensity, short pulse laser interacting with matter under conditions relevant to Fast Ignition. Bremsstrahlung x-rays produced by these fast electrons were measured by a set of compact filter-stack based x-ray detectors placed at three angles with respect to the target. The measured bremsstrahlung signal allows a characterization of the fast electron beam spectrum, conversion efficiency of laser energy into fast electron kinetic energy and angular distribution. A Monte Carlo code Integrated Tiger Series was used to model the bremsstrahlung signal and infer a laser to fast electron conversion efficiency of 30%, an electron slope temperature of about 2.2 MeV, and a mean divergence angle of 39°. Simulations were also performed with the hybrid transport code ZUMA which includes fields in the target. In this case, a conversion efficiency of laser energy to fast electron energy of 34% and a slope temperature between 1.5 MeV and 4 MeV depending on the angle between the target normal direction and the measuring spectrometer are found. The observed temperature of the bremsstrahlung spectrum, and therefore the inferred electron spectrum are found to be angle dependent.

  16. Characterization of the fast electrons distribution produced in a high intensity laser target interaction

    SciTech Connect

    Westover, B.; Chen, C. D.; Patel, P. K.; McLean, H.; Beg, F. N.

    2014-03-15

    Experiments on the Titan laser (∼150 J, 0.7 ps, 2 × 10{sup 20} W cm{sup −2}) at the Lawrence Livermore National Laboratory were carried out in order to study the properties of fast electrons produced by high-intensity, short pulse laser interacting with matter under conditions relevant to Fast Ignition. Bremsstrahlung x-rays produced by these fast electrons were measured by a set of compact filter-stack based x-ray detectors placed at three angles with respect to the target. The measured bremsstrahlung signal allows a characterization of the fast electron beam spectrum, conversion efficiency of laser energy into fast electron kinetic energy and angular distribution. A Monte Carlo code Integrated Tiger Series was used to model the bremsstrahlung signal and infer a laser to fast electron conversion efficiency of 30%, an electron slope temperature of about 2.2 MeV, and a mean divergence angle of 39°. Simulations were also performed with the hybrid transport code ZUMA which includes fields in the target. In this case, a conversion efficiency of laser energy to fast electron energy of 34% and a slope temperature between 1.5 MeV and 4 MeV depending on the angle between the target normal direction and the measuring spectrometer are found. The observed temperature of the bremsstrahlung spectrum, and therefore the inferred electron spectrum are found to be angle dependent.

  17. Local influence of south-east France topography and land cover on the distribution and characteristics of intense rainfall cells

    NASA Astrophysics Data System (ADS)

    Renard, Florent

    2016-01-01

    The Greater Lyon area is strongly built up, grouping 58 communes and a population of 1.3 million in approximately 500 km2. The flood risk is high as the territory is crossed by two large watercourses and by streams with torrential flow. Floods may also occur in case of runoff after heavy rain or because of a rise in the groundwater level. The whole territory can therefore be affected, and it is necessary to possess in-depth knowledge of the depths, causes and consequences of rainfall to achieve better management of precipitation in urban areas and to reduce flood risk. This study is thus focused on the effects of topography and land cover on the occurrence, intensity and area of intense rainfall cells. They are identified by local radar meteorology (C-band) combined with a processing algorithm running in a geographic information system (GIS) which identified 109,979 weighted mean centres of them in a sample composed of the five most intense rainfall events from 2001 to 2005. First, analysis of spatial distribution at an overall scale is performed, completed by study at a more detailed scale. The results show that the distribution of high-intensity rainfall cells is spread in cluster form. Subsequently, comparison of intense rainfall cells with the topography shows that cell density is closely linked with land slope but that, above all, urbanised zones feature nearly twice as many rainfall cells as farm land or forest, with more intense intensity.

  18. Spectral evolution of non-thermal electron distributions in intense radiation fields

    NASA Astrophysics Data System (ADS)

    Manolakou, K.; Horns, D.; Kirk, J. G.

    2007-11-01

    Context: Models of many astrophysical gamma-ray sources assume they contain a homogeneous distribution of electrons that are injected as a power law in energy and evolve by interacting with radiation fields, magnetic fields, and particles in the source and by escaping. This problem is particularly complicated if the radiation fields have higher energy density than the magnetic field and are sufficiently energetic that inverse Compton scattering is not limited to the Thomson regime. Aims: We present a simple, time-dependent, semi-analytical solution to the electron kinetic equation that treats both continuous and impulsive injection, cooling via synchrotron and inverse Compton radiation (taking Klein-Nishina effects into account), and energy-dependent particle escape. We used this solution to calculate the temporal evolution of the multi-wavelength spectrum of systems where energetic electrons cool in intense photon fields. Methods: The kinetic equation for an arbitrary, time-dependent source function is solved by the method of Laplace transformations. Using an approximate expression for the energy-loss rate that takes synchrotron and inverse Compton losses into account, including Klein-Nishina effects for scattering off an isotropic photon field with either a power-law or black-body distribution, we find explicit expressions for the cooling time and escape probability of individual electrons. This enables the full, time-dependent solution to be reduced to a single quadrature. From the electron distribution, we then construct the time-dependent, multi-wavelength emission spectrum. Results: We compare our solutions with several limiting cases and discuss the general appearance and temporal behaviour of spectral features (i.e., cooling breaks, bumps, etc.). As a specific example, we model the broad-band energy spectrum of the open stellar association Westerlund-2 at different times of its evolution, and compare it with observations. The model calculation matches the

  19. The Aquatic Systems Continuum

    NASA Astrophysics Data System (ADS)

    Winter, T. C.

    2004-12-01

    The Aquatic Systems Continuum is a proposed framework for interrelating the physical, chemical, and biological characteristics of aquatic ecosystems. The continuum can be represented by a three-dimensional matrix that relates aquatic ecosystems to their position within hydrologic flow paths (x-axis, a spatial dimension) and their response to climate variability (y-axis). The z-axis describes the structure of biological communities as they relate to the hydrological conditions defined by the x and y axes. The concept is an extension of the Wetland Continuum that was derived from field studies of a prairie pothole wetland complex in North Dakota. At that site, the hydrologic continuum in space is defined by ground-water flow systems. The wetlands are surface-water expressions of larger ground-water watersheds, in which wetlands serve recharge, flow-through, and discharge functions with respect to ground water. The water balance of the wetlands is dominated by precipitation and evaporation. However, the interaction of the wetlands with ground water, although a small part of their water budget, provides the primary control on delivery of major solutes to and from the wetlands. Having monitored these wetlands for more than 25 years, during which time the site had a complete range of climate conditions from drought to deluge, the response of the aquatic communities to a wide variety of climate conditions has been well documented. The Aquatic Systems Continuum extends the model provided by the Wetland Continuum to include rivers and their interaction with ground water. As a result, both ground water and surface water are used to describe terrestrial water flows for all types of aquatic ecosystems. By using the Aquatic Systems Continuum to describe the hydrologic flow paths in all types of terrain, including exchange with atmospheric water, it is possible to design studies, monitoring programs, and management plans for nearly any type of aquatic ecosystem.

  20. A comparison of intensity modulated x-ray therapy to intensity modulated proton therapy for the delivery of non-uniform dose distributions

    NASA Astrophysics Data System (ADS)

    Flynn, Ryan

    2007-12-01

    The distribution of biological characteristics such as clonogen density, proliferation, and hypoxia throughout tumors is generally non-uniform, therefore it follows that the optimal dose prescriptions should also be non-uniform and tumor-specific. Advances in intensity modulated x-ray therapy (IMXT) technology have made the delivery of custom-made non-uniform dose distributions possible in practice. Intensity modulated proton therapy (IMPT) has the potential to deliver non-uniform dose distributions as well, while significantly reducing normal tissue and organ at risk dose relative to IMXT. In this work, a specialized treatment planning system was developed for the purpose of optimizing and comparing biologically based IMXT and IMPT plans. The IMXT systems of step-and-shoot (IMXT-SAS) and helical tomotherapy (IMXT-HT) and the IMPT systems of intensity modulated spot scanning (IMPT-SS) and distal gradient tracking (IMPT-DGT), were simulated. A thorough phantom study was conducted in which several subvolumes, which were contained within a base tumor region, were boosted or avoided with IMXT and IMPT. Different boosting situations were simulated by varying the size, proximity, and the doses prescribed to the subvolumes, and the size of the phantom. IMXT and IMPT were also compared for a whole brain radiation therapy (WBRT) case, in which a brain metastasis was simultaneously boosted and the hippocampus was avoided. Finally, IMXT and IMPT dose distributions were compared for the case of non-uniform dose prescription in a head and neck cancer patient that was based on PET imaging with the Cu(II)-diacetyl-bis(N4-methylthiosemicarbazone (Cu-ATSM) hypoxia marker. The non-uniform dose distributions within the tumor region were comparable for IMXT and IMPT. IMPT, however, was capable of delivering the same non-uniform dose distributions within a tumor using a 180° arc as for a full 360° rotation, which resulted in the reduction of normal tissue integral dose by a factor of

  1. Determination of Stress Intensity Factor Distributions for "Interface" Cracks in Incompressible, Dissimilar Materials

    NASA Technical Reports Server (NTRS)

    Smith, C. W.

    1997-01-01

    The present study was undertaken in order to develop test methods and procedures for measuring the variation of the stress intensity factor through the thickness in bimaterial specimens containing cracks within and parallel to the bond line using the frozen stress photoelastic method. Since stress freezing materials are incompressible above critical temperature, and since thick plates are to be employed which tend to produce a state of plane strain near the crack tip, the interface near tip fracture equations reduce to the classic form for homogeneous materials. Moreover, zero thickness interfaces do not exist when materials are bonded together. It was decided early on that it would be important to insure a uniform straight and accurate crack tip region through the thickness of the body to reduce scatter in the SIF distribution through the thickness. It was also observed that rubberlike materials which were desired to be modeled exhibited significant tip blunting prior to crack extension and that some blunting of the tip would provide a more realistic model. It should be noted that, in normal stress freezing photoelastic work, it is considered good practice to avoid utilizing data near bond lines in photoelastic models due to the bond line stresses which inevitably develop when two parts are bonded together. Thus, the present study involves certain exploratory aspects in deviating from standard practice in stress freezing work. With the above ideas in mind, several different test methods were investigated and are described in the following sections and appendices. The geometry selected for the program was a thick, edge cracked specimen containing a bond line.

  2. Tropical Cyclone Lightning Distribution and Its Relationship to Convection and Intensity Change

    NASA Technical Reports Server (NTRS)

    Rodgers, Edward; Wienman, James; Pierce, Harold; Olson, William

    2000-01-01

    The long distance National Lightning Detection Network (NLDN) was used to monitor the distribution of lightning strokes in various 1998 and 1999 western North Atlantic tropical cyclones. These ground-based lightning observations together with the Defense Meteorological Satellite Program (DMSP) Special Sensor Microwave/Imager (SSM/I) and the Tropical Rain Mapping Mission (TRMM) Microwave Instrument (TMI) derived convective rain rates were used to monitor the propagation of electrically charged convective rain bands aid to qualitatively estimate intensification. An example of the lightning analyses was performed on hurricane George between 25-28 September, 1998 when the system left Key West and moved towards the Louisiana coast. During this period of time, George's maximum winds increased from 38 to 45 meters per second on 25 September and then remained steady state until it made landfall. Time-radius displays of the lightning strokes indicated that the greatest number of lightning strokes occurred within the outer core region (greater than 165 km) with little or no lightning strokes at radii less than 165 km. The trend in these lightning strokes decreased as George move into the Gulf of Mexico and showed no inward propagation. The lack inward propagating lightning strokes with time indicated that there was no evidence that an eye wall replacement was occurring that could alter George's intensity. Since George was steady state at this time, this result is not surprising. Time-azimuth displays of lightning strokes in an annulus whose outer and inner radii were respectively, 222 and 333 km from George's center were also constructed. A result from this analysis indicated that the maximum number of strokes occurred in the forward and rear right quadrant when George was over the Gulf of Mexico. This result is, consistent with the aircraft and satellite observations of maximum rainfall.

  3. Impact of Urbanization on Precipitation Distribution and Intensity over Lake Victoria Basin

    NASA Astrophysics Data System (ADS)

    Gudoshava, M.; Semazzi, F. H. M.

    2014-12-01

    In this study, sensitivity simulations on the impact of rapid urbanization over Lake Victoria Basin in East Africa were done using a Regional Climate Model (RegCM4.4-rc29) with the Hostetler lake model activated. The simulations were done for the rainy seasons that is the long rains (March-April-May) and short rains (October-November-December). Africa is projected to have a surge in urbanization with an approximate rate of 590% in 2030 over their 2000 levels. The Northern part of Lake Victoria Basin and some parts of Rwanda and Burundi are amongst the regions with high urbanization projections. Simulations were done with the land cover for 2000 and the projected 2030 urbanization levels. The results showed that increasing the urban fraction over the northern part of the basin modified the physical parameters such as albedo, moisture and surface energy fluxes, aerodynamic roughness and surface emissivity, thereby altering the precipitation distribution, intensity and frequency in the region. The change in the physical parameters gave a response of an average increase in temperature of approximately 2oC over the urbanized region. A strong convergence zone was formed over the urbanized region and thereby accelerating the lake-breeze front towards the urbanized region center. Precipitation in the urbanized region and regions immediate to the area increased by approximately 4mm/day, while drying up the southern (non-urbanized) side of the basin. The drying up of the southern side of the basin could be a result of divergent flow and subsidence that suppresses vertical development of storms.

  4. Examining the Psychosis Continuum

    PubMed Central

    DeRosse, Pamela; Karlsgodt, Katherine H.

    2015-01-01

    The notion that psychosis may exist on a continuum with normal experience has been proposed in multiple forms throughout the history of psychiatry. However, in recent years there has been an exponential increase in efforts aimed at elucidating what has been termed the ‘psychosis continuum’. The present review seeks to summarize some of the more basic characteristics of this continuum and to present some of the recent findings that provide support for its validity. While there is still considerable work to be done, the emerging data holds considerable promise for advancing our understanding of both risk and resilience to psychiatric disorders characterized by psychosis. PMID:26052479

  5. Cosmic ray intensity distribution perpendicular to solar equatorial plane at 1 A.U. during 1978-83

    NASA Technical Reports Server (NTRS)

    Pathak, S. P.; Agrawal, S. P.; Shrivastava, P. K.; Yadav, R. S.

    1985-01-01

    The distribution of cosmic ray intensity perpendicular to solar equatorial plane, was investigated by using its yearly variation with respect to the heliolatitudinal position of the Earth, for the two intervals 1978 to 1980 and 1981 to 1983. The monthly mean values of two high latitude stations along with the solar and geomagnetic indices are used to derive the cosmic ray intensity distribution free from the changes due to variation in solar activity. The correction is found to be significant only during the interval 1976 to 1980. The results indicate a significant linear increase in cosmic ray intensity from north to south of solar equator, contrary to that observed during 1973 to 1975. No symmetrical gradients are found during the period of study, in agreement with earlier results.

  6. Quantum-mechanical analysis of the intensity distribution in spectra of resonant Raman scattering spectra of aqueous solutions of tyrosine

    NASA Astrophysics Data System (ADS)

    Burova, T. G.; Shcherbakov, R. S.

    2016-05-01

    Quantum-mechanical calculations of the intensity distribution in the resonant Raman scattering spectra of aqueous solutions of tyrosine excited by laser radiation with wavelengths of 244, 229, 218, 200, and 193 nm, as well as in the nonresonant Raman scattering spectrum excited at a wavelength of 488 nm, are performed. Satisfactory agreement is achieved between the calculation results and the experimental data. It is shown that the changes in the intensity distribution observed in the spectra with a change in the excitation wavelength from 244 to 193 nm correlate with the determined changes in the contribution made by excited electronic states into the scattering tensor components. It is noted that it is necessary to take into account the Herzberg-Teller effect and that the number of excited electronic states taken into account considerably affects the calculated relative intensities of lines. The possibility of existence of several tyrosine conformers in aqueous solution at room temperature is shown.

  7. Continuum capture in the three-body problem

    SciTech Connect

    Sellin, I A

    1980-01-01

    The three-body problem, especially the problem of electron capture to the continuum in heavy particle collisions is reviewed. Major topics covered include: second born-induced asymmetry in electron capture to the continuum; historical context, links to other tests of atomic scattering theory; experiments characterizing the velocity distribution of ECC electrons; other atomic physics tests of high velocity Born expansions; atom capture; capture by positrons; and pion capture to the continuum. (GHT)

  8. Evolution dynamics of charge state distribution in neon interaction with x-ray pulses of variant intensities and durations

    NASA Astrophysics Data System (ADS)

    Gao, Cheng; Zeng, Jiaolong; Yuan, Jianmin

    2015-03-01

    The level population and charge state distribution (CSD) of the neon atomic system interacting with x-ray pulses of variant intensities and durations at a central photon energy of 1110 eV are investigated by solving the time-dependent rate equations. The laser beam has a circular spot size with a Gaussian intensity pattern and the time history of the intensity is represented by Gaussian distribution in time. As an example, the CSD as a function of time is given at different distances from the spot center for an x-ray beam of intensity 1.5 × 1017 W/cm2 and duration 75 fs (fs) for a spot size of 1 μm (full width at half maximum). The final CSD after averaging over the space and time is compared with a recent experiment and good agreement is found between the theory and experiment. Then systematic investigations are carried out to study the evolution of CSD with a wide range of intensity from 1.0 × 1015 W/cm2 to 1.0 × 1019 W/cm2 and duration from 30 fs to 100 fs. The results show that at intensities lower than 1.0 × 1015 W/cm2, the CSD shows a typical physical picture of weak x-ray photoionization of the neutral atomic neon. At higher intensity, i.e., larger than 5.0 × 1016 W/cm2, the dominant ionization stages are Ne7+ and Ne8+, while the fractions of ions in the Ne3+-Ne6+ stages are low for all laser durations and intensities.

  9. LETTER TO THE EDITOR: Distortion of molecular electron density distributions by an intense laser field: dissociative ionization of ?

    NASA Astrophysics Data System (ADS)

    Vijayalakshmi, K.; Bhardwaj, V. R.; Safvan, C. P.; Mathur, D.

    1997-05-01

    The interaction of a tetrahedral molecule (carbon tetrachloride) with intense, 532 nm, 35 ps, 0953-4075/30/10/003/img2 linearly polarized, laser fields is explored theoretically and experimentally. Distortions caused by the laser field in the molecular electron density distributions are computed in an approximate fashion using quantum-chemical techniques. A comparative experimental study is performed of the dissociative ionization of 0953-4075/30/10/003/img3 in such an intense laser field and also by electron impact. Significant differences are observed and attempts are made to explore the possibility that these can be explained using field-distorted electron density distributions. Angular distributions of the 0953-4075/30/10/003/img4 fragment ion have also been measured and show a pronounced anisotropy with the ion signal being detected mainly along the direction of the laser's polarization axis.

  10. The Continuum of Listening

    ERIC Educational Resources Information Center

    Rud, A. G.; Garrison, Jim

    2007-01-01

    The distinction between "apophatic" and "cataphatic" listening is defined and analyzed. "Apophatic" listening is more or less devoid of cognitivist claims, whereas "cataphatic" listening involves cognition and questioning. Many of the papers in this volume are discussed along the continuum determined by these two types of listening.…

  11. Teacher Education: A Continuum.

    ERIC Educational Resources Information Center

    Momentum, 1990

    1990-01-01

    This document is a theme issue of the journal "Momentum", devoted to the topic "Teacher Education: A Continuum." It contains 15 articles in the central section and 7 articles in a special section subtitled "The Multicultural Challenge." The following articles on the central theme are presented: (1) "Closing the Gap" concerns fusing the college and…

  12. The Creativity Continuum

    ERIC Educational Resources Information Center

    Walling, Donovan R.

    2009-01-01

    Children are innately creative, and the youngest often are the most original because they have yet to be influenced by the creativity of others. One way to think of creative expression is as a continuum. At one end is originality, or the creation of something wholly new, "original." At the other end is replication, or the re-creation of something…

  13. Extragalactic continuum sources.

    NASA Astrophysics Data System (ADS)

    Valtaoja, E.

    1989-09-01

    As with most other high-frequency radio telescopes, continuum work occupies only a small fraction - currently about 5% - of SEST's total time. The importance of these observations in increasing our understanding of quasars and other extragalactic sources is, however, large.

  14. Studies on light intensity distribution inside an open pond photo-bioreactor.

    PubMed

    Pandey, Ramakant; Sahu, Akhilesh; K K, Vasumathi; M, Premalatha

    2015-08-01

    Light intensity profiles inside an open tank were studied using ANSYS Fluent. Experiments were performed by taking Scenedesmus arcuatus, green microalgae at three different concentrations under actual sunlight conditions. Absorption of light intensity at different depths was measured experimentally. The results generated from CFD simulations were compared with the experimental results and the cornet model. It has been found that there is a good agreement between the light intensity profile obtained from the CFD simulation and that calculated using the Cornet's model. Light intensity profiles at different depths were calculated using CFD simulation by varying the dimensions of the tank. The effect of wall reflectivity, diffuse fraction and scattering phase function on light profile in side open tank are also studied using CFD simulation. PMID:25868715

  15. Intensity distribution and isoseismal maps for the Nisqually, Washington, earthquake of 28 February 2001

    USGS Publications Warehouse

    Dewey, James W.; Hopper, Margaret G.; Wald, David J.; Quitoriano, Vincent; Adams, Elizabeth R.

    2002-01-01

    We present isoseismal maps, macroseismic intensities, and community summaries of damage for the MW=6.8 Nisqually, Washington, earthquake of 28 February, 2001. For many communities, two types of macroseismic intensity are assigned, the traditional U.S. Geological Survey Modified Mercalli Intensities (USGS MMI) and a type of intensity newly introduced with this paper, the USGS Reviewed Community Internet Intensity (RCII). For most communities, the RCII is a reviewed version of the Community Internet Intensity (CII) of Wald and others (1999). For some communities, RCII is assigned from such non-CII sources as press reports, engineering reports, and field reconnaissance observations. We summarize differences between procedures used to assign RCII and USGS MMI, and we show that the two types of intensity are nonetheless very similar for the Nisqually earthquake. We do not see evidence for systematic differences between RCII and USGS MMI that would approach one intensity unit, at any level of shaking, but we document a tendency for the RCII to be slightly lower than MMI in regions of low intensity and slightly higher than MMI in regions of high intensity. The highest RCII calculated for the Nisqually earthquake is 7.6, calculated for zip code 98134, which includes the ?south of downtown? (Sodo) area of Seattle and Harbor Island. By comparison, we assigned a traditional USGS MMI 8 to the Sodo area of Seattle. In all, RCII of 6.5 and higher were assigned to 58 zip-code regions. At the lowest intensities, the Nisqually earthquake was felt over an area of approximately 350,000 square km (approximately 135,000 square miles) in Washington, Oregon, Idaho, Montana, and southern British Columbia, Canada. On the basis of macroseismic effects, we infer that shaking in the southern Puget Sound region was somewhat less for the 2001 Nisqually earthquake than for the Puget Sound earthquake of April 13, 1949, which had nearly the same hypocenter and magnitude. Allowing for differences

  16. A Scheduling Algorithm for the Distributed Student Registration System in Transaction-Intensive Environment

    ERIC Educational Resources Information Center

    Li, Wenhao

    2011-01-01

    Distributed workflow technology has been widely used in modern education and e-business systems. Distributed web applications have shown cross-domain and cooperative characteristics to meet the need of current distributed workflow applications. In this paper, the author proposes a dynamic and adaptive scheduling algorithm PCSA (Pre-Calculated…

  17. Generalized Kapchinskij-Vladimirskij Distribution and Envelope Equation for High-intensity Beams in a Coupled Transverse Focusing Lattice

    SciTech Connect

    Hong Qin, Moses Chung, and Ronald C. Davidson

    2009-11-20

    In an uncoupled lattice, the Kapchinskij-Vladimirskij (KV) distribution function first analyzed in 1959 is the only known exact solution of the nonlinear Vlasov-Maxwell equations for high- intensity beams including self-fields in a self-consistent manner. The KV solution is generalized here to high-intensity beams in a coupled transverse lattice using the recently developed generalized Courant-Snyder invariant for coupled transverse dynamics. This solution projects to a rotating, pulsating elliptical beam in transverse configuration space, determined by the generalized matrix envelope equation.

  18. Wide-Area Mapping of 155 Micron Continuum Emission from the Orion Molecular Cloud Complex

    NASA Astrophysics Data System (ADS)

    Arimura, Seikoh; Shibai, Hiroshi; Teshima, Takafumi; Nakagawa, Takao; Narita, Masanao; Makiuti, Shin'itirou; Doi, Yasuo; Verma, Ram Prakash; Ghosh, Swarna Kanti; Rengarajan, Thinnian Naganathan; Tanaka, Makoto; Okuda, Haruyuki

    2004-02-01

    We present the results of a wide-area mapping of the far-infrared continuum emission toward the Orion complex by using a Japanese balloon-borne telescope. The 155-μm continuum emission was detected over a region of 1.5 deg2 around the KL nebula with 3‧ resolution similar to that of the IRAS 100-μm map. Assuming a single-temperature model of the thermal equilibrium dust, maps of the temperature and the optical thickness were derived from the 155-μm intensity and the IRAS 100-μm intensity. The derived dust temperature is 5-15K lower and the derived dust optical depth is 5-300 times larger than those derived from the IRAS 60 and 100-μm intensities due to the significant contribution of the statistically heated very small grains to the IRAS 60-μm intensity. The optical-thickness distribution shows a filamentary dust ridge that has a 1°.5 extent in the north-south direction and well resembles the Integral-Shaped Filament (ISF) molecular gas distribution. The gas-to-dust ratio derived from the CO molecular gas distribution along the ISF is in the range 30-200, which may be interpreted as being an effect of CO depletion due to the photodissociation and/or the freezing on dust grains.

  19. The fluorescence intermittency for quantum dots is not power-law distributed: a luminescence intensity resolved approach.

    PubMed

    Schmidt, Robert; Krasselt, Cornelius; Göhler, Clemens; von Borczyskowski, Christian

    2014-04-22

    The photoluminescence (PL) of single emitters like semiconductor quantum dots (QDs) shows PL intermittency, often called blinking. We explore the PL intensities of single CdSe/ZnS QDs in polystyrene (PS), on polyvenylalcohol (PVA), and on silicon oxide (SiOx) by the change-point analysis (CPA). By this, we relate results from the macrotime (sub-ms to 1000 s) and the microtime (0.1-100 ns) range to discrete PL intensities. We conclude that the intensity selected "on"-times in the ms range correspond to only a few (discrete) switching times, while the PL decays in the ns range are multiexponential even with respect to the same selected PL intensity. Both types of relaxation processes depend systematically on the PL intensity in course of a blinking time trace. The overall distribution of on-times does not follow a power law contrary to what has often been reported but can be compiled into 3-4 characteristic on-times. The results can be explained by the recently suggested multiple recombination centers model. Additionally, we can identify a well-defined QD state with a very low PL intensity above the noise level, which we assign to the strongly quenched exciton state. We describe our findings by a model of a hierarchical sequence of hole and electron trapping. Blinking events are the consequence of slow switching processes among these states and depend on the physicochemical properties of the heterogeneous nanointerface of the QDs. PMID:24580107

  20. Unexpected spatial intensity distributions and onset timing of solar electron events observed by closely spaced STEREO spacecraft

    NASA Astrophysics Data System (ADS)

    Klassen, A.; Dresing, N.; Gómez-Herrero, R.; Heber, B.; Müller-Mellin, R.

    2016-09-01

    We present multi-spacecraft observations of four solar electron events using measurements from the Solar Electron Proton Telescope (SEPT) and the Electron Proton Helium INstrument (EPHIN) on board the STEREO and SOHO spacecraft, respectively, occurring between 11 October 2013 and 1 August 2014, during the approaching superior conjunction period of the two STEREO spacecraft. At this time the longitudinal separation angle between STEREO-A (STA) and STEREO-B (STB) was less than 72°. The parent particle sources (flares) of the four investigated events were situated close to, in between, or to the west of the STEREO's magnetic footpoints. The STEREO measurements revealed a strong difference in electron peak intensities (factor ≤12) showing unexpected intensity distributions at 1 AU, although the two spacecraft had nominally nearly the same angular magnetic footpoint separation from the flaring active region (AR) or their magnetic footpoints were both situated eastwards from the parent particle source. Furthermore, the events detected by the two STEREO imply a strongly unexpected onset timing with respect to each other: the spacecraft magnetically best connected to the flare detected a later arrival of electrons than the other one. This leads us to suggest the concept of a rippled peak intensity distribution at 1 AU formed by narrow peaks (fingers) superposed on a quasi-uniform Gaussian distribution. Additionally, two of the four investigated solar energetic particle (SEP) events show a so-called circumsolar distribution and their characteristics make it plausible to suggest a two-component particle injection scenario forming an unusual, non-uniform intensity distribution at 1 AU.

  1. Determination of plume temperature distribution based on the ratios of the radiation intensities of multiple CO2 lines

    NASA Astrophysics Data System (ADS)

    Cieszczyk, S.

    2015-05-01

    New inversion scheme for gas temperature distribution retrieval utilized CO2 spectrum between 2350 cm-1 and 2400 cm-1 is proposed. Inversion model is build base on neural networks. Considered spectral remote sensing method is commonly used for industrial and environmental monitoring. It is a passive single-ended sensor technique in which radiation intensity emerging from a studied object is analyzed. Quantitative investigation of heated gas radiation emission to determine temperature and gas mixture by infrared spectroscopy requires two components apart from optical radiation sensor. First appropriate spectral database and second efficient inversion techniques. In this study calculation of one-dimensional radiative transfer equation have been used for simulation of spectral radiation intensity. To increase quality of retrieval a spectrum preprocessing and feature extraction method is applied. Simulated spectra were parameterized and expressed as ratios of intensities of multiple rotational lines. Each neural network estimates temperature (NN response) at one point on studied path basing on given spectrum (NN input).

  2. Enhancing a Distributed Rainfall Intensity for Flood Analysis within a GIS Framework in an Urban Area (Kajang Flood)

    NASA Astrophysics Data System (ADS)

    Salleh, S. H. M.; Sidek, L. M.

    2016-03-01

    The town of Kajang has experienced major flood events in previous decades since 1970s. Due to Eastern and Western Monsoon seasons in Malaysia, Kajang has potential to face with number of flood events. One of the critical elements in flood analysis is rainfall distribution. Therefore, flood studies need to have an optimum cognition of rainfall distribution as main input. In this study, HEC GeoHMS model was used in GIS (Geographic Information System) for Sungai Jeluh catchment (Kajang) due to estimation (visualization) of distributed rainfall in Kajang. In comparison with conventional methods, which they produced rainfall in lumped mode (e.g. Thiessen’s polygon), HEC GeoHMS visualized and tabulate a full distribution of rainfall for each small part (pixel of map) in a case study. HEC GeoHMS model for Sungai Jeluh has been set up by feeding high resolution of spatial and temporal resolution data (precipitation). Result of this study shows that rainfall by high intensity is distributed near urban area (downtown) in comparison with upstream which involved with less rainfall intensity.

  3. Outer coronal structure and relative intensity distribution observed during the total solar eclipse on March 9, 1997 in Mohe.

    NASA Astrophysics Data System (ADS)

    Li, Qiusha; Zhang, Bairong

    With a simple video-collecting system, the total solar eclipse on March 9, 1997 has been observed by using Panasonic NV-S88OEN video camera in Mohe. After analyzing the yellow (by adding a GG11 filter) and white coronal observation data, the outer coronal structure and relative intensity distribution outside 1.5 Rsun have been found during the solar minima.

  4. Conductivity of continuum percolating systems

    NASA Astrophysics Data System (ADS)

    Stenull, Olaf; Janssen, Hans-Karl

    2001-11-01

    We study the conductivity of a class of disordered continuum systems represented by the Swiss-cheese model, where the conducting medium is the space between randomly placed spherical holes, near the percolation threshold. This model can be mapped onto a bond percolation model where the conductance σ of randomly occupied bonds is drawn from a probability distribution of the form σ-a. Employing the methods of renormalized field theory we show to arbitrary order in ɛ expansion that the critical conductivity exponent of the Swiss-cheese model is given by tSC(a)=(d-2)ν+max[φ,(1-a)-1], where d is the spatial dimension and ν and φ denote the critical exponents for the percolation correlation length and resistance, respectively. Our result confirms a conjecture that is based on the ``nodes, links, and blobs'' picture of percolation clusters.

  5. Distribution of secondary particles intensities over Earth's surface: Effect of the geomagnetic field

    NASA Astrophysics Data System (ADS)

    Bobik, P.; Kudela, K.; Pastircak, B.; Santangelo, A.; Bertaina, M.; Shinozaki, K.; Fenu, F.; Szabelski, J.; Urbar, J.

    2012-10-01

    We use the CORSIKA package (Heck et al., 1998) and AMS-01 flight data (Alcaraz et al., 2000) to evaluate the distribution of secondary particles in the Earth atmosphere. Distribution covers all longitudes and latitudes of STS-91 Space Shuttle flight trajectory to Mir Space Station. Moreover distribution covers all depth in the atmosphere in the evaluated area. We show distributions for e-, e+, μ+, μ-, gammas, hadrons and Cherenkov light from primary protons and helium component of cosmic rays flux. Our results compare favorably with other estimates made by different techniques. We also estimate an UV light production (300-400 nm) by electron component of secondaries at the top of the atmosphere and at ISS orbit.

  6. Stress distributions and stress intensity factors in ceramic roller bearing rings

    NASA Astrophysics Data System (ADS)

    Müller, W. H.

    1995-06-01

    A method is presented which allows to compute the stress intensity factors (SIFs) of a ceramic roller bearing ring with a surface flaw. First, the stresses due to mechanical loads applied to the surfaces of the undamaged ring are computed, using Michell's expression for Airy's stress function in polar coordinates ([l]). Second, the stress intensity factors of the flaw are obtained using Tada's additivity principle ([2]), namely by integration of the point force solution for the SIF of a surface crack with the aforementioned stresses as input parameter. To illustrate the procedure, the special case of a ring with a surface flaw which is loaded by six equidistantly spaced cylindrical rollers will be studied numerically.

  7. Initial assessment of the intensity distribution of the 2011 Mw5.8 Mineral, Virginia, earthquake

    USGS Publications Warehouse

    Hough, Susan E.

    2012-01-01

    The intensity data collected by the U.S. Geological Survey (USGS) "Did You Feel It?" (DYFI) Website (USGS, DYFI; http://earthquake.usgs.gov/earthquakes/dyfi/events/se/082311a/us/index.html, last accessed Sept 2011) for the Mw5.8 Mineral, Virginia, earthquake, are unprecedented in their spatial richness and geographical extent. More than 133,000 responses were received during the first week following the earthquake. Although intensity data have traditionally been regarded as imprecise and generally suspect (e.g., Hough 2000), there is a growing appreciation for the potential utility of spatially rich, systematically determined DYFI data to address key questions in earthquake ground-motions science (Atkinson and Wald, 2007; Hauksson et al., 2008).

  8. Inferring local competition intensity from patch size distributions: a test using biological soil crusts

    USGS Publications Warehouse

    Bowker, Matthew A.; Maestre, Fernando T.

    2012-01-01

    Dryland vegetation is inherently patchy. This patchiness goes on to impact ecology, hydrology, and biogeochemistry. Recently, researchers have proposed that dryland vegetation patch sizes follow a power law which is due to local plant facilitation. It is unknown what patch size distribution prevails when competition predominates over facilitation, or if such a pattern could be used to detect competition. We investigated this question in an alternative vegetation type, mosses and lichens of biological soil crusts, which exhibit a smaller scale patch-interpatch configuration. This micro-vegetation is characterized by competition for space. We proposed that multiplicative effects of genetics, environment and competition should result in a log-normal patch size distribution. When testing the prevalence of log-normal versus power law patch size distributions, we found that the log-normal was the better distribution in 53% of cases and a reasonable fit in 83%. In contrast, the power law was better in 39% of cases, and in 8% of instances both distributions fit equally well. We further hypothesized that the log-normal distribution parameters would be predictably influenced by competition strength. There was qualitative agreement between one of the distribution's parameters (μ) and a novel intransitive (lacking a 'best' competitor) competition index, suggesting that as intransitivity increases, patch sizes decrease. The correlation of μ with other competition indicators based on spatial segregation of species (the C-score) depended on aridity. In less arid sites, μ was negatively correlated with the C-score (suggesting smaller patches under stronger competition), while positive correlations (suggesting larger patches under stronger competition) were observed at more arid sites. We propose that this is due to an increasing prevalence of competition transitivity as aridity increases. These findings broaden the emerging theory surrounding dryland patch size distributions

  9. Observations of angular distributions of low energy electron intensities over the auroral zones with Ariel 4

    NASA Technical Reports Server (NTRS)

    Craven, J. D.; Frank, L. A.

    1975-01-01

    The electron intensities considered are within the energy range from 244 eV to 10.8 keV. The measurements were made at an altitude of about 570 km over the local-evening sector of the auroral zone. Aspects of instrumentation are discussed along with details regarding the observations, energy-time spectrograms, the signature of the plasma sheet, and inverted V events. The initial results reported provide new information concerning auroral acceleration mechanisms.

  10. Inversion of photometric He+ (30.4 nm) intensities to obtain He+ distributions

    NASA Astrophysics Data System (ADS)

    Garrido, Dante E.; Smith, Roger W.; Marsh, C. A.; Christensen, Andrew B.; Chakrabarti, Supriya

    1993-07-01

    Radiation at He(superscript +) at 30.4 nm, which is emitted close to the Earth, comes from three distinct regions; the ionosphere, the plasmasphere and the polar cap. Published observational data on He(superscript +) 30.4 nm have shown that the intensities from polar regions are relatively smaller than the other regions. Polar emissions are believed to be due to resonant scattering of ion outflow in sunlight. A 1982 rocket flight from Poker Flat, Alaska has shown that line-of-sight 30.4 nm emission rates are relatively strong in the direction of the pole. Since the roll of the rocket afforded many different observing directions, we have used the variety of viewing geometries to extract ionospheric source densities from the photometric intensity data. We have assumed that the He(superscript +) densities vary with distance along dipole field lines according to a particular functional form, and then we proceeded to extract the source densities by a matrix inversion method. The results give density variations over a range of latitudes including samples from each of the regions mentioned above. The method obtains good fits of the observed profiles of intensity versus observation angle.

  11. The Response Continuum

    SciTech Connect

    Caltagirone, Sergio; Frincke, Deborah A.

    2005-06-17

    Active response is a sequence of actions per- formed speci¯cally to mitigate a detected threat. Response decisions always follow detection: a decision to take `no ac- tion' remains a response decision. However, active response is a complex subject that has received insu±cient formal attention. To facilitate discussion, this paper provides a framework that proposes a common de¯nition, describes the role of response and the major issues surrounding response choices, and ¯nally, provides a model for the process of re- sponse. This provides a common starting point for discus- sion of the full response continuum as an integral part of contemporary computer security.

  12. ISO continuum observations of quasars at z=1-4. I. Spectral energy distributions of quasars from the UV to far-infrared

    NASA Astrophysics Data System (ADS)

    Oyabu, S.; Kawara, K.; Tsuzuki, Y.; Sofue, Y.; Sato, Y.; Okuda, H.; Taniguchi, Y.; Shibai, H.; Gabriel, C.; Hasegawa, T.; Nishihara, E.

    2001-01-01

    Eight luminous quasars with -30 < MB < -27 at z = 1.4-3.7 have been observed in the mid- and far-infrared using ISO. All the quasars have been detected in the mid-infrared bands of ISOCAM, while no far-infrared detections have been made with ISOPHOT. SEDs (Spectral Energy Distributions) from the UV to far-infrared have been obtained while supplementing ISO observations with photometry in the optical and near-infrared made from the ground within 17 months. The SEDs are compared with the MED (Mean spectral Energy Distributions) of low-redshift quasars with -27 < MB < -22. It is shown that our far-infrared observations were limited by confusion noise due to crowded sources. The observations reported here were made with ISO, an ESA project with instruments funded by ESA member states (especially the PI countries: France, Germany, The Netherlands, and the UK) and with the participation of ISAS and NASA, and with the facilities at the Cerro Tololo Inter-american Observatory (CTIO), NOAO, which is operated by AURA, Inc., under contract with NSF, at the Kiso Observatory, which is operated by Institute of Astronomy, the University of Tokyo, and at the Okayama Astrophysical Observatory, the National Astronomical Observatory of Japan.

  13. Formation of a conical distribution and intense ion heating in the presence of hydrogen cyclotron waves

    NASA Astrophysics Data System (ADS)

    Okuda, H.; Ashour-Abdalla, M.

    1981-07-01

    In the considered investigation, it is assumed that the field aligned currents are responsible for producing electrostatic harmonic cyclotron waves (EHC). Using a one-dimensional simulation model in which the electron velocity distribution is maintained by a constant injection of the initial distribution, it is shown that, in contrast to earlier initial value simulations, EHC waves grow to a large amplitude, resulting in the formation of an anisotropic ion velocity distribution. Both the heating rate and the anisotropy are in reasonable agreement with the quasi-linear theory, taking into account the cyclotron resonance. The results show that the saturation is due to the combined effects of wave induced diffusion in an electron velocity space and the heating of ions perpendicularly. Both these effects reduce the growth rate.

  14. Compression of femtosecond pulses with a Gaussian temporal and spatial intensity distribution

    SciTech Connect

    Mironov, S Yu; Lozhkarev, V V; Khazanov, E A; Mourou, G

    2013-08-31

    The possibility of using the cubic self-action effect of intense radiation for the additional time compression of Gaussian beams with a quasi-uniform cross section is investigated. The ability to recompress 30-fs Gaussian pulses down to 14 fs (16 fs) with the heterogeneity of less than 1.5 fs (2 fs) on the spatial scale, which corresponds to the energy level 63% (86%) of the beam, is theoretically demonstrated at the B-integral of ∼3. (control of laser radiation parameters)

  15. Investigation on the Influence of Different Laser Beam Intensity Distributions on Keyhole Geometry During Laser Welding

    NASA Astrophysics Data System (ADS)

    Volpp, J.

    An analytical quasi-static model of the keyhole during laser deep penetration welding is introduced. This model is used to calculate the keyhole geometry depending on spatial laser beam intensity. Keyhole shapes can be found solving the energy and pressure equations. All necessary physical effects like Fresnel and plasma absorption, heat conduction and vaporization are implemented in the model. For evaluation a Gaussian and a top hat beam profile were used. Experimental measurements of the keyhole shape using copper inlays in aluminum base material show good agreement with the results of the modeling.

  16. Validation of clinical activity tracking system in Intensive Care Unit to assess nurse workload distribution.

    PubMed

    Peng Guo; Yeong Shiong Chiew; Shaw, Geoff; Chase, Geoff

    2015-08-01

    Therapeutic Intervention Score System (TISS-28) and the Nursing Activities Score (NAS) are common used to evaluate nursing workload in the Intensive Care Unit (ICU). However, they require experienced researchers to perform, are subject to user bias and experience, and are labor intensive, which all exclude regular use. A Clinical Activities Tracking System (CATS) was developed to evaluate bedside nursing activities automatically. This paper presents the validation of this system in quantifying bedside nursing activities. A total of 30 hours (1 hour/day) of nursing activities were manually recorded by trained researcher. The manually recorded total time spent on bedside nursing activities (Atime) was compared with time recorded using CATS (Ctime). A high correlation was found between Atime and Ctime with R = 0.882, and thus the actual time spent in nursing activity can be estimated using a first order polynomial function. In this study, it was found that the median Atime between 7 am-10 pm is 1.4-1.5 times higher than nursing activities at 10 pm-7 am. Results showed that CATS was able to provide unique and high information on patient bedside nursing activities. PMID:26736298

  17. Modification of the velocity distribution of H(2) molecules in a supersonic beam by intense pulsed optical gradients.

    PubMed

    Ramirez-Serrano, Jaime; Strecker, Kevin E; Chandler, David W

    2006-07-01

    We report the acceleration and deceleration of H(2) molecules in a supersonic molecular beam by means of its interaction with an intense optical gradient from a nanosecond far-off-resonant optical pulse. The strong optical gradients are formed in the interference pattern of two intense optical pulses at 532 nm. The velocity distribution of the molecular beam, before and after the applied optical pulse, is measured by a velocity-mapped ion imaging technique. Changes in velocity up to 202 m s(-1)+/- 61 m s(-1) are observed in a molecular beam initially travelling at a mean speed of 563 m s(-1). We report the dependence of this change in velocity with the strength of the optical gradient applied. PMID:16880911

  18. Classification of knowledge-intensive organizations

    NASA Astrophysics Data System (ADS)

    Marquart, Edward J.

    Managing knowledge workers in knowledge-intensive organizations has become important because knowledge itself is emerging as a primary sustainable competitive advantage. This dissertation traces the development of two important items related to knowledge-intensive organizations. First, it documents a careful study of the literature which allows for the construction of a Knowledge-Intensity Continuum. This continuum then forms the basis for the development of a Knowledge-Intensity Assessment survey instrument which allows an organization to be placed along this continuum. A cross-section of research, consulting, and manufacturing organizations was surveyed using this instrument. The findings provided evidence that supports the validity of the Knowledge-Intensity Continuum. Additionally, onsite interviews provided evidence that the Knowledge-Intensity Assessment survey can be used as a tool to locate any organization on this continuum. Using this survey to clearly identify knowledge-intensive organizations will allow for further research into effective management systems for knowledge workers in these organizations.

  19. A methodology to study multiple sclerosis (MS) based on distributions of standardized intensities in segmented tissue regions

    NASA Astrophysics Data System (ADS)

    Lei, T.; Udupa, J. K.; Odhner, D.; Mishra, S.; Wu, G.; Schwartz, E.; Ying, G.-S.; Iwanaga, T.; Desiderio, L.; Balcer, L.

    2006-03-01

    This paper presents (1) an improved hierarchical method for segmenting the component tissue regions in fast spin echo T2 and PD images of the brain of Multiple Sclerosis (MS) patients, and (2) a methodology to characterize the disease utilizing the distributions of standardized T2 and PD intensities in the segmented tissue regions. First, the background intensity inhomogeneities are corrected and the intensity scales are standardized for all acquired images. The segmentation method imposes a feedback-like procedure on our previously developed hierarchical brain tissue segmentation method. With gradually simplified patterns in images and stronger evidences, pathological objects are recognized and segmented in an interplay fashion. After the brain parenchymal (BP) mask is generated, an under-estimated gray matter mask (uGM) and an over-estimated white matter mask (oWM) are created. Pure WM (PWM) and lesion (LS) masks are extracted from the all-inclusive oWM mask. By feedback, accurate GM and WM masks are subsequently formed. Finally, partial volume regions of GM and WM as well as Dirty WM (DWM) masks are generated. Intensity histograms and their parameters (peak height, peak location, and 25th, 50th and 75th percentile values) are computed for both T2 and PD images within each tissue region. Tissue volumes are also estimated. Spearman correlation coefficient rank test is then utilized to assess if there exists a trend between clinical states and the image-based parameters. This image analysis method has been applied to a data set consisting of 60 patients with MS and 20 normal controls. LS related parameters and clinical Extended Disability Status Scale (EDSS) scores demonstrate modest correlations. Almost every intensity-based parameter shows statistical difference between normal control and patient groups with a level better than 5%. These results can be utilized to monitor disease progression in MS.

  20. Atmospheric velocity spectral width measurements using the statistical distribution of pulsed CO2 lidar return signal intensities

    NASA Technical Reports Server (NTRS)

    Ancellet, Gerard M.; Menzies, Robert T.; Grant, William B.

    1989-01-01

    A pulsed CO2 lidar with coherent detection has been used to measure the correlation time of backscatter from an ensemble of atmospheric aerosol particles which are illuminated by the pulsed radiation. The correlation time of the backscatter of the return signal, which is directly related to the velocity spectral width, can be used to study the velocity structure constant of atmospheric turbulence and wind shear. Various techniques for correlation time measurement are discussed, and several measurement results are presented for the technique using the information contained in the statistical distribution of a set of lidar return signal intensities.

  1. Models of Uranium continuum radio emission

    NASA Technical Reports Server (NTRS)

    Romig, Joseph H.; Evans, David R.; Sawyer, Constance B.; Schweitzer, Andrea E.; Warwick, James W.

    1987-01-01

    Uranium continuum radio emission detected by the Voyager 2 Planetary Radio Astronomy experiment during the January 1986 encounter is considered. The continuum emissions comprised four components (equatorial emissions, anomaly emissions, strong nightside emissions, and weak nightside emissions) associated with different sources. The equatorial emissions appeared most prominently during the days before closest approach and extended from 40 kHz or below to about 120 kHz. The anomaly emissions were seen about 12 hours before closest approach and extended to about 250 kHz. The agreement found between Miranda's phase and strong radio emission at 20.4 kHz, just after closest approach, suggests intense dynamic activity on the Miranda L shell.

  2. High-Intensity Radiated Field Fault-Injection Experiment for a Fault-Tolerant Distributed Communication System

    NASA Technical Reports Server (NTRS)

    Yates, Amy M.; Torres-Pomales, Wilfredo; Malekpour, Mahyar R.; Gonzalez, Oscar R.; Gray, W. Steven

    2010-01-01

    Safety-critical distributed flight control systems require robustness in the presence of faults. In general, these systems consist of a number of input/output (I/O) and computation nodes interacting through a fault-tolerant data communication system. The communication system transfers sensor data and control commands and can handle most faults under typical operating conditions. However, the performance of the closed-loop system can be adversely affected as a result of operating in harsh environments. In particular, High-Intensity Radiated Field (HIRF) environments have the potential to cause random fault manifestations in individual avionic components and to generate simultaneous system-wide communication faults that overwhelm existing fault management mechanisms. This paper presents the design of an experiment conducted at the NASA Langley Research Center's HIRF Laboratory to statistically characterize the faults that a HIRF environment can trigger on a single node of a distributed flight control system.

  3. Decreased plasma albumin concentration results in increased volume of distribution and decreased elimination of midazolam in intensive care patients.

    PubMed

    Vree, T B; Shimoda, M; Driessen, J J; Guelen, P J; Janssen, T J; Termond, E F; van Dalen, R; Hafkenscheid, J C; Dirksen, M S

    1989-11-01

    The pharmacokinetic parameters of 16 patients in the intensive care unit, sedated with midazolam, were evaluated. A large variation was observed in the plasma concentration of midazolam and between the plasma concentration of midazolam and its metabolite 1-hydroxymethylmidazolam glucuronide. The plasma albumin concentration governs the volume of distribution of midazolam. Decreased plasma albumin concentration (25 gm/L) results in an increased volume of distribution and a decreased elimination rate of midazolam. The observed plasma concentration ratio between the parent drug and its metabolite 1-hydroxymethylmidazolam glucuronide is governed by the variables of protein binding, the metabolic rate of midazolam, and the renal clearance of the glucuronide metabolite itself (which can be considered as a measure of the kidney function of the patient). PMID:2582710

  4. Intensity-modulated linear-frequency-modulated continuous-wave lidar for distributed media: fundamentals of technique.

    PubMed

    Batet, Oscar; Dios, Federico; Comeron, Adolfo; Agishev, Ravil

    2010-06-10

    We analyze the intensity-modulation frequency-modulated continuous-wave (FMCW) technique for lidar remote sensing in the context of its application to distributed media. The goal of the technique is the reproduction of the sounded-medium profile along the emission path. A conceptual analysis is carried out to show the problems the basic version of the method presents for this application. The principal point is the appearance of a bandpass filtering effect, which seems to hinder its use in this context. A modified version of the technique is proposed to overcome this problem. A number of computer simulations confirm the ability of the modified FMCW technique to sound distributed media. PMID:20539357

  5. Angular distribution in two-photon double ionization of helium by intense attosecond soft-x-ray pulses

    NASA Astrophysics Data System (ADS)

    Barna, Imre F.; Wang, Jianyi; Burgdörfer, Joachim

    2006-02-01

    We investigate two-photon double ionization of helium by intense (≈1015W/cm2) ultrashort (≈300as) soft-x-ray pulses (E=91.6eV) . The time-dependent two-electron Schrödinger equation is solved using a coupled channel method. We show that for ultrashort pulses the angular distribution of ejected electrons depends on the pulse duration and provides insight into the role of electron correlations in the two-electron photoemission process. The angular distribution at energies near the “independent-electron” peaks is close to dipolar while it acquires in the “valley” of correlated emission a significant quadrupolar component within a few hundred attoseconds.

  6. Temperature distribution in biotissues under cw low-intensity laser irradiation

    NASA Astrophysics Data System (ADS)

    Yakunin, Alexander N.; Scherbakov, Yury N.; Tuchin, Valery V.; Utz, Sergei R.; Yaroslavsky, Ilya V.

    1992-08-01

    The Monte Carlo method of statistical simulations was used to evaluate the effects of anisotropic scattering and refractive index mismatch at the boundaries of the medium on light and temperature distribution in the multilayered biotissues during laser irradiation. The influence of optical parameters of multilayered tissue on its stationary thermal response was examined by using an adaptive version of finite element solution of the heat conduction equation. Calculations were performed for two models of human skin and adjacent tissues for visible (five layer model) and UV (three layer model) ranges of wavelengths. The topic of this paper is especially pertinent to laser percutaneous irradiation of blood and laser PUVA therapy.

  7. Evaluation of gafchromic EBT film for intensity modulated radiation therapy dose distribution verification

    PubMed Central

    Sankar, A.; Kurup, P. G. Goplakrishna; Murali, V.; Ayyangar, Komanduri M.; Nehru, R. Mothilal; Velmurugan, J.

    2006-01-01

    This work was undertaken with the intention of investigating the possibility of clinical use of commercially available self-developing radiochromic film – Gafchromic EBT film – for IMRT dose verification. The dose response curves were generated for the films using VXR-16 film scanner. The results obtained with EBT films were compared with the results of Kodak EDR2 films. It was found that the EBT film has a linear response between the dose ranges of 0 and 600 cGy. The dose-related characteristics of the EBT film, like post-irradiation color growth with time, film uniformity and effect of scanning orientation, were studied. There is up to 8.6% increase in the color density between 2 and 40 h after irradiation. There was a considerable variation, up to 8.5%, in the film uniformity over its sensitive region. The quantitative difference between calculated and measured dose distributions was analyzed using Gamma index with the tolerance of 3% dose difference and 3 mm distance agreement. EDR2 films showed good and consistent results with the calculated dose distribution, whereas the results obtained using EBT were inconsistent. The variation in the film uniformity limits the use of EBT film for conventional large field IMRT verification. For IMRT of smaller field size (4.5 × 4.5 cm), the results obtained with EBT were comparable with results of EDR2 films. PMID:21206669

  8. Spatiotemporal dynamics of continuum neural fields

    NASA Astrophysics Data System (ADS)

    Bressloff, Paul C.

    2012-01-01

    We survey recent analytical approaches to studying the spatiotemporal dynamics of continuum neural fields. Neural fields model the large-scale dynamics of spatially structured biological neural networks in terms of nonlinear integrodifferential equations whose associated integral kernels represent the spatial distribution of neuronal synaptic connections. They provide an important example of spatially extended excitable systems with nonlocal interactions and exhibit a wide range of spatially coherent dynamics including traveling waves oscillations and Turing-like patterns.

  9. Continuous Exercise but Not High Intensity Interval Training Improves Fat Distribution in Overweight Adults

    PubMed Central

    Keating, Shelley E.; Machan, Elizabeth A.; O'Connor, Helen T.; Gerofi, James A.; Sainsbury, Amanda; Caterson, Ian D.; Johnson, Nathan A.

    2014-01-01

    Objective. The purpose of this study was to assess the effect of high intensity interval training (HIIT) versus continuous aerobic exercise training (CONT) or placebo (PLA) on body composition by randomized controlled design. Methods. Work capacity and body composition (dual-energy X-ray absorptiometry) were measured before and after 12 weeks of intervention in 38 previously inactive overweight adults. Results. There was a significant group × time interaction for change in work capacity (P < 0.001), which increased significantly in CONT (23.8 ± 3.0%) and HIIT (22.3 ± 3.5%) but not PLA (3.1 ± 5.0%). There was a near-significant main effect for percentage trunk fat, with trunk fat reducing in CONT by 3.1 ± 1.6% and in PLA by 1.1 ± 0.4%, but not in HIIT (increase of 0.7 ± 1.0%) (P = 0.07). There was a significant reduction in android fat percentage in CONT (2.7 ± 1.3%) and PLA (1.4 ± 0.8%) but not HIIT (increase of 0.8 ± 0.7%) (P = 0.04). Conclusion. These data suggest that HIIT may be advocated as a time-efficient strategy for eliciting comparable fitness benefits to traditional continuous exercise in inactive, overweight adults. However, in this population HIIT does not confer the same benefit to body fat levels as continuous exercise training. PMID:24669314

  10. Bloodstream infections in intensive care unit patients: distribution and antibiotic resistance of bacteria

    PubMed Central

    Russotto, Vincenzo; Cortegiani, Andrea; Graziano, Giorgio; Saporito, Laura; Raineri, Santi Maurizio; Mammina, Caterina; Giarratano, Antonino

    2015-01-01

    Bloodstream infections (BSIs) are among the leading infections in critically ill patients. The case-fatality rate associated with BSIs in patients admitted to intensive care units (ICUs) reaches 35%–50%. The emergence and diffusion of bacteria with resistance to antibiotics is a global health problem. Multidrug-resistant bacteria were detected in 50.7% of patients with BSIs in a recently published international observational study, with methicillin resistance detected in 48% of Staphylococcus aureus strains, carbapenem resistance detected in 69% of Acinetobacter spp., in 38% of Klebsiella pneumoniae, and in 37% of Pseudomonas spp. Prior hospitalization and antibiotic exposure have been identified as risk factors for infections caused by resistant bacteria in different studies. Patients with BSIs caused by resistant strains showed an increased risk of mortality, which may be explained by a higher incidence of inappropriate empirical therapy in different studies. The molecular genetic characterization of resistant bacteria allows the understanding of the most common mechanisms underlying their resistance and the adoption of surveillance measures. Knowledge of epidemiology, risk factors, mechanisms of resistance, and outcomes of BSIs caused by resistant bacteria may have a major influence on global management of ICU patients. The aim of this review is to provide the clinician an update on BSIs caused by resistant bacteria in ICU patients. PMID:26300651