Science.gov

Sample records for piezometric surface mapping

  1. A method for aquifer and piezometric surface mapping with a cone penetrometer

    SciTech Connect

    Aggarwal, P.K.; Burton, J.C.; Meyer, W.T.; Stefano, J.E.

    1994-04-01

    The electronic cone penetrometer (ECPT) is increasingly being used for environmental characterization of hazardous waste sites, especially to delineate subsurface lithology and to obtain samples of groundwater. A potentially powerful use of the ECPT is the mapping of subsurface hydrostratigraphic features and aquifer piezometric surface(s) by using measurements of pore pressure. Most published studies on the use of the ECPT have been limited to shallow sand-clay sequences and indicate only limited success in hydrogeologic characterization. In this paper, we discuss a method for delineating the depth and thicknesses of unsaturated and saturated zones on the basis of the nature and rate of pore pressure dissipation. We have used this method to depths of 110 ft at several sites underlaid by clay-sand or weathered shale-limestone sequences. The equilibrium pore pressures in the saturated zone should ideally indicate the depth of the water table or aquifer piezometric surface; however, our data indicate that an apparent equilibrium value for pore pressures may be obtained that may be lower or higher than the true value, depending on the composition and grain size of the material in the aquifer, the depth of the dissipation test within the saturated zone, and the history of use of the porous filter in the cone penetrometer assembly. Consequently, the data on dissipation must be carefully calibrated and tested with measurements in a monitoring well before the data are used to determine piezometric surfaces.

  2. NIMS Ganymede Surface Map

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Galileo has eyes that can see more than ours can. By looking at what we call the infrared wavelengths, the NIMS (Near Infrared Mapping Spectrometer) instrument can determine what type and size of material is on the surface of a moon. Here, 3 images of Ganymede are shown.

    Left: Voyager's camera.

    Middle: NIMS, showing water ice on the surface. Dark is less water, bright is more.

    Right: NIMS, showing the locations of minerals in red, and the size of ice grains in shades of blue.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov.

  3. Mapping stellar surface features

    SciTech Connect

    Noah, P.V.

    1987-01-01

    New photometric and spectroscopic observations of the RS Canum Venaticorum binaries Sigma Geminorum and UX Arietis are reported along with details of the Doppler-imaging program SPOTPROF. The observations suggest that the starspot activity on Sigma Gem has decreased to 0.05 magnitude in two years. A photometric spot model for September 1984 to January 1985 found that a single spot covering 2% of the surface and 1000 K cooler than the surrounding photosphere could model the light variations. Equivalent-width observations contemporaneous with the photometric observations did not show any significant variations. Line-profile models from SPOTPROF predict that the variation of the equivalent width of the 6393 A Fe I line should be approx. 1mA. Photometric observations of UX Ari from January 1984 to March 1985 show an 0.3 magnitude variation indicating a large spot group must cover the surface. Contemporaneous spectroscopic observations show asymmetric line profiles. The Doppler imaging and the photometric light-curve models were used in an iterative method to describe the stellar surface-spot distribution and successfully model both the photometric and the spectroscopic variations.

  4. Mapping products of Titan's surface

    USGS Publications Warehouse

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

    2009-01-01

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

  5. Vesta surface thermal properties map

    USGS Publications Warehouse

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

    2014-01-01

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

  6. Piezometric response in shallow bedrock at CB1: Implications for runoff generation and landsliding

    NASA Astrophysics Data System (ADS)

    Montgomery, David R.; Dietrich, William E.; Heffner, John T.

    2002-12-01

    Experimental observations comparing two steep unchanneled valleys in the Oregon Coast Range, one intensively instrumented (CB1) and the other monitored for runoff but which produced a debris flow (CB2), shed light on the mechanisms of shallow flow in bedrock, its interaction with the vadose zone, and its role in generating landslides. Previous work at CB1 led to the proposal that during storms pulses of rainfall transmit pressure waves through the vadose zone and down to the saturated zone to create rapid pore pressure response and runoff [, 1998]. Here, we document the associated rapid pore pressure response in the shallow fractured bedrock that underlies these colluvium-mantled sites and examine its influence on the generation of storm flow, seasonal variations in base flow, and slope stability in the overlying colluvial soil. Our observations document rapid piezometric response in the shallow bedrock and a substantial contribution of shallow fracture flow to both storm flow and seasonal variations in base flow. Saturated hydraulic conductivity in the colluvial soil decreases with depth below the ground surface, but the conductivity of the near-surface bedrock displays no depth dependence and varies over five orders of magnitude. Analysis of runoff intensity and duration in a series of storms that did and did not trigger debris flows in the surrounding area shows that the landslide inducing storms had the greatest intensity over durations similar to those predicted by a simple model of piezometric response. During a monitored storm in February 1992, the channel head at the base of the neighboring CB2 site failed as a debris flow. Automated piezometric measurements document that the CB2 debris flow initiated several hours after peak discharge, coincident with localized development of upward spikes of pressure head from near-surface bedrock into the overlying colluvial soil in CB1. Artesian flow observed exfiltrating from bedrock fractures on the failure surfaces

  7. On selecting a body surface mapping procedure.

    PubMed

    Hoekema, R; Uijen, G J; van Oosterom, A

    1999-04-01

    Throughout the world, various procedures related to body surface mapping have evolved. The large differences in these procedures make multicenter studies difficult. This paper discusses the problems involved in selecting the number of leads, lead placement, and map format. Methods are highlighted that have been developed for pooling of the data as obtained by different centers. Recommendations are included to newcomers in the field. (The work stems from an international study, the Noninvasive Evaluation of the Myocardium, a study group sponsored by the European Commission, which has as one of its objectives the standardization of body surface mapping procedures.)

  8. Absorption mapping for characterization of glass surfaces.

    PubMed

    Commandré, M; Roche, P; Borgogno, J P; Albrand, G

    1995-05-01

    The surface quality of bare substrates and preparation procedures take on an important role in optical coating performances. The most commonly used techniques of characterization generally give information about roughness and local defects. A photothermal deflection technique is used for mapping surface absorption of fused-silica and glass substrates. We show that absorption mapping gives specific information on surface contamination of bare substrates. We present experimental results concerning substrates prepared by different cleaning and polishing techniques. We show that highly polished surfaces lead to the lowest values of residual surface absorption. Moreover the cleaning behavior of surfaces of multicomponent glasses and their optical performance in terms of absorption are proved to be different from those of fused silica.

  9. COMPLETE SURFACE MAPPING OF ICF SHELLS

    SciTech Connect

    STEPHENS,R.B; OLSON,D; HUANG,H; GIBSON,J.B

    2003-06-01

    OAK-B135 Inertial confinement fusion shells have previously been evaluated on the basis of microscopic examination for local defects and limited surface profiling to represent their average fluctuation power. Since defects are local, and don't always have visible edges, this approach both misses some important fluctuations and doesn't properly represent the spatially dependent surface fluctuation power. they have taken the first step toward correcting this problem by demonstrating the capability to completely map the surface of a NIF shell with the resolution to account for all modes. This allows complete accounting of all the surface fluctuations. In the future this capability could be used for valuable shells to generate a complete r({theta},{psi}) surface map for accurate 3-D modeling of a shot.

  10. Complete Surface Mapping of ICF Shells

    SciTech Connect

    Stephens, R.B.; Olson, D.; Huang, H.; Gibson, J.B.

    2004-03-15

    Inertial confinement fusion shells have previously been evaluated on the basis of microscopic examination for local defects and limited surface profiling to represent their average fluctuation power. Since defects are local, and don't always have visible edges, this approach both misses some important fluctuations and doesn't properly represent the spatially dependent surface fluctuation power. We have taken the first step toward correcting this problem by demonstrating the capability to completely map the surface of a NIF shell with the resolution to account for all modes. This allows complete accounting of all the surface fluctuations. In the future this capability could be used for valuable shells to generate a complete r({theta}, {phi}) surface map for accurate 3-D modeling of a shot.

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

    NASA Astrophysics Data System (ADS)

    Christensen, W.; Fogg, G. E.

    2010-12-01

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

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

    NASA Astrophysics Data System (ADS)

    Mechergui, M. Mohamed; Henda Saoudi, Mme

    2016-04-01

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

  13. Shadows for bump-mapped surfaces

    SciTech Connect

    Max, N.L.

    1985-11-05

    Bump mapping produces realistic shading by perturbing normal vectors to a surface, but does not show the shadows that the bumps cast on nearby parts of the same surface. In this paper, these shadows are found from precomputed tables of horizon angles, listing, for each position entry, the elevation of the horizon in a sampled collection of directions. These tables are made for bumps on a standard flat surface, and then a transformation is developed so that the same tables can be used for an arbitrary curved parameterized surface patch. This necessitates a new method for scaling the bump size to the patch size. 7 refs., 8 figs.

  14. Impervious surface mapping with Quickbird imagery

    PubMed Central

    Lu, Dengsheng; Hetrick, Scott; Moran, Emilio

    2010-01-01

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

  15. High Resolution Camera for Mapping Titan Surface

    NASA Technical Reports Server (NTRS)

    Reinhardt, Bianca

    2011-01-01

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

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

    USGS Publications Warehouse

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

    2010-01-01

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

  17. Fermi surface mapping: Techniques and visualization

    SciTech Connect

    Rotenberg, E.; Denlinger, J. D.; Kevan, S. D.; Goodman, K. W.; Tobin, J. G.; Mankey, G. J.

    1997-04-01

    Angle-resolved photoemission (ARP) of valence bands is a mature technique that has achieved spectacular success in band-mapping metals, semiconductors, and insulators. The purpose of the present study was the development of experimental and analytical techniques in ARP which take advantage of third generation light sources. Here the authors studied the relatively simple Cu surface in preparation for other metals. Copper and related metals themselves are of current interest, especially due to its role as an interlayer in spin valves and other magnetic heterostructures. A major goal of this study was the development of a systematic technique to quickly (i.e. in a few hours of synchrotron beamtime) measure the FS and separate it into bulk and surface FS`s. Often, one needs to avoid bulk features altogether, which one can achieve by carefully mapping their locations in k-space. The authors will also show how they systematically map Fermi surfaces throughout large volumes of k-space, and, by processing the resulting volume data sets, provide intuitive pictures of FS`s, both bulk and surface.

  18. GIS Surface Effects Map Archive, Nevada Test Site, Nevada

    SciTech Connect

    Grasso, Dennis N.

    2003-08-28

    The GIS Surface Effects Map Archive contains a comprehensive collection of maps showing the surface effects produced by underground nuclear testing at the Nevada Test Site. From 1951 to 1992, scientists with the U.S. Geological Survey and agencies of the U.S. Department of Energy used field and aerial-photo mapping techniques to painstakingly map such surface effects as collapse sinks, craters, cracks, fractures, faults, and pressure ridges. Shortly after each test, a complex surface effects map was produced. Of the more than 920 underground detonations conducted at the Nevada Test Site, 688 were mapped for surface effects. This archive preserves these original maps in digital format. A Geographic Information System (GIS) was used to digitally reproduce each original, hand-drawn surface effects map and to assemble these maps into the digital data sets of this archive. The archive was designed to allow easy access to the maps, while preserving the original maps for perpetuity. Users can query the detonation sites database; prepare, view, and print individual or composite maps; and perform various types of scientific analysis and management tasks. Spatial analyses and queries can be performed on detonation sites and related surface effects in conjunction with other chronological, geographical, geological, or hydrological information via links to external maps and databases. This browser interface provides information about the archive, the history of surface effects mapping at the Nevada Test Site, the methods used to produce the digital surface effects maps, and links to published reports, data tables, and maps. Location maps show testing areas, operational areas, and detonation sites. Demonstration maps illustrate the methods used to produce the digital surface effects maps and exhibit some of the characteristics and uses for these data. Use the links below to view and print individual surface effects maps, retrieve information about the detonations and types of

  19. Charge heterogeneity of surfaces: mapping and effects on surface forces.

    PubMed

    Drelich, Jaroslaw; Wang, Yu U

    2011-07-11

    The DLVO theory treats the total interaction force between two surfaces in a liquid medium as an arithmetic sum of two components: Lifshitz-van der Waals and electric double layer forces. Despite the success of the DLVO model developed for homogeneous surfaces, a vast majority of surfaces of particles and materials in technological systems are of a heterogeneous nature with a mosaic structure composed of microscopic and sub-microscopic domains of different surface characteristics. In such systems, the heterogeneity of the surface can be more important than the average surface character. Attractions can be stronger, by orders of magnitude, than would be expected from the classical mean-field DLVO model when area-averaged surface charge or potential is employed. Heterogeneity also introduces anisotropy of interactions into colloidal systems, vastly ignored in the past. To detect surface heterogeneities, analytical tools which provide accurate and spatially resolved information about material surface chemistry and potential - particularly at microscopic and sub-microscopic resolutions - are needed. Atomic force microscopy (AFM) offers the opportunity to locally probe not only changes in material surface characteristic but also charges of heterogeneous surfaces through measurements of force-distance curves in electrolyte solutions. Both diffuse-layer charge densities and potentials can be calculated by fitting the experimental data with a DLVO theoretical model. The surface charge characteristics of the heterogeneous substrate as recorded by AFM allow the charge variation to be mapped. Based on the obtained information, computer modeling and simulation can be performed to study the interactions among an ensemble of heterogeneous particles and their collective motions. In this paper, the diffuse-layer charge mapping by the AFM technique is briefly reviewed, and a new Diffuse Interface Field Approach to colloid modeling and simulation is briefly discussed.

  20. Surface charge mapping with a nanopipette.

    PubMed

    McKelvey, Kim; Kinnear, Sophie L; Perry, David; Momotenko, Dmitry; Unwin, Patrick R

    2014-10-01

    Nanopipettes are emerging as simple but powerful tools for probing chemistry at the nanoscale. In this contribution the use of nanopipettes for simultaneous surface charge mapping and topographical imaging is demonstrated, using a scanning ion conductance microscopy (SICM) format. When a nanopipette is positioned close to a surface in electrolyte solution, the direct ion current (DC), driven by an applied bias between a quasi-reference counter electrode (QRCE) in the nanopipette and a second QRCE in the bulk solution, is sensitive to surface charge. The charge sensitivity arises because the diffuse double layers at the nanopipette and the surface interact, creating a perm-selective region which becomes increasingly significant at low ionic strengths (10 mM 1:1 aqueous electrolyte herein). This leads to a polarity-dependent ion current and surface-induced rectification as the bias is varied. Using distance-modulated SICM, which induces an alternating ion current component (AC) by periodically modulating the distance between the nanopipette and the surface, the effect of surface charge on the DC and AC is explored and rationalized. The impact of surface charge on the AC phase (with respect to the driving sinusoidal signal) is highlighted in particular; this quantity shows a shift that is highly sensitive to interfacial charge and provides the basis for visualizing charge simultaneously with topography. The studies herein highlight the use of nanopipettes for functional imaging with applications from cell biology to materials characterization where understanding surface charge is of key importance. They also provide a framework for the design of SICM experiments, which may be convoluted by topographical and surface charge effects, especially for small nanopipettes.

  1. Dawn Maps the Surface Composition of Vesta

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

  2. Protein Flexibility in Docking and Surface Mapping

    PubMed Central

    Lexa, Katrina W.; Carlson, Heather A.

    2012-01-01

    Structure-based drug design has become an essential tool for rapid lead discovery and optimization. As available structural information has increased, researchers have become increasingly aware of the importance of protein flexibility for accurate description of the native state. Typical protein–ligand docking efforts still rely on a single rigid receptor, which is an incomplete representation of potential binding conformations of the protein. These rigid docking efforts typically show the best performance rates between 50 and 75%, while fully flexible docking methods can enhance pose prediction up to 80–95%. This review examines the current toolbox for flexible protein–ligand docking and receptor surface mapping. Present limitations and possibilities for future development are discussed. PMID:22569329

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

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

  4. Anomalous increases in piezometric levels in advance of longwall mining subsidence

    USGS Publications Warehouse

    Booth, C.J.; Curtiss, A.M.; DeMaris, P.J.; Van Roosendaal, D. J.

    1999-01-01

    The typical initial piezometric response to longwall undermining is a decline in head due to the opening of fractures and bedding planes during early subsidence. However, in studies over two active longwall mines in southern Illinois, temporary rises in head just before subsidence were observed in piezometers constructed in low-permeability units. Although the initial phase of subsidence is considered dilational, these head increases indicate compressional effects that raise pore-water pressures. Possible mechanisms are shear stresses at the leading edge of subsidence or transmission of stress related to dewatering of underlying permeable units.

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

    NASA Technical Reports Server (NTRS)

    Rasor, N. S.

    1966-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Chiba, T.; Hasi, B.

    2016-06-01

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

  7. Surface-material maps of Viking landing sites on Mars

    NASA Technical Reports Server (NTRS)

    Moore, H. J.; Keller, J. M.

    1991-01-01

    Researchers mapped the surface materials at the Viking landing sites on Mars to gain a better understanding of the materials and rock populations at the sites and to provide information for future exploration. The maps extent to about 9 m in front of each lander and are about 15 m wide - an area comparable to the area of a pixel in high resolution Viking Orbiter images. The maps are divided into the near and far fields. Data for the near fields are from 1/10 scale maps, umpublished maps, and lander images. Data for the far fields are from 1/20 scale contour maps, contoured lander camera mosaics, and lander images. Rocks are located on these maps using stereometric measurements and the contour maps. Frequency size distribution of rocks and the responses of soil-like materials to erosion by engine exhausts during landings are discussed.

  8. Surface-material maps of Viking landing sites on Mars

    NASA Astrophysics Data System (ADS)

    Moore, H. J.; Keller, J. M.

    1991-06-01

    Researchers mapped the surface materials at the Viking landing sites on Mars to gain a better understanding of the materials and rock populations at the sites and to provide information for future exploration. The maps extent to about 9 m in front of each lander and are about 15 m wide - an area comparable to the area of a pixel in high resolution Viking Orbiter images. The maps are divided into the near and far fields. Data for the near fields are from 1/10 scale maps, umpublished maps, and lander images. Data for the far fields are from 1/20 scale contour maps, contoured lander camera mosaics, and lander images. Rocks are located on these maps using stereometric measurements and the contour maps. Frequency size distribution of rocks and the responses of soil-like materials to erosion by engine exhausts during landings are discussed.

  9. Direct Mapping of Hippocampal Surfaces with Intrinsic Shape Context

    PubMed Central

    Shi, Yonggang; Thompson, Paul M.; de Zubicaray, Greig I.; Rose, Stephen E.; Tu, Zhuowen; Dinov, Ivo; Toga, Arthur W.

    2007-01-01

    We propose in this paper a new method for the mapping of hippocampal (HC) surfaces to establish correspondences between points on HC surfaces and enable localized HC shape analysis. A novel geometric feature, the intrinsic shape context, is defined to capture the global characteristics of the HC shapes. Based on this intrinsic feature, an automatic algorithm is developed to detect a set of landmark curves that are stable across population. The direct map between a source and target HC surface is then solved as the minimizer of a harmonic energy function defined on the source surface with landmark constraints. For numerical solutions, we compute the map with the approach of solving partial differential equations on implicit surfaces. The direct mapping method has the following properties: 1) it has the advantage of being automatic; 2) it is invariant to the pose of HC shapes. In our experiments, we apply the direct mapping method to study temporal changes of HC asymmetry in Alzheimer disease (AD) using HC surfaces from 12 AD patients and 14 normal controls. Our results show that the AD group has a different trend in temporal changes of HC asymmetry than the group of normal controls. We also demonstrate the flexibility of the direct mapping method by applying it to construct spherical maps of HC surfaces. Spherical harmonics (SPHARM) analysis is then applied and it confirms our results about temporal changes of HC asymmetry in AD. PMID:17625918

  10. A New Perspective on Surface Weather Maps

    ERIC Educational Resources Information Center

    Meyer, Steve

    2006-01-01

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

  11. Global Energetic Neutral Atom Map of the Lunar Surface

    NASA Astrophysics Data System (ADS)

    Vorburger, Audrey; Wurz, Peter; Barabash, Stas; Wieser, Martin; Futaana, Yoshifumi; Lue, Charles; Holmström, Mats; Bhardwaj, Anil; Dhanya, Mb; Asamura, Kazushi

    2013-04-01

    Until recently, it was tacitly assumed that the solar wind ions that impinge onto the lunar surface are almost completely absorbed ( < 1% reflection). This assumption has been invalidated by recent observations made by IBEX and SARA/Chandrayaan-1, which showed an average global energetic neutral atom (ENA) albedo of 10% - 20% (e.g. McComas et al. [GRL 2009] and Wieser et al. [PSS, 2009]). Having analysed all available measurements from the Chandrayaan-1 Energetic Neutral Analyzer (SARA/CENA), we present two global ENA maps of the lunar surface. The low energy map contains ENAs in the energy range (7 eV - 169 eV) and the high energy map contains ENAs in the energy range (169 eV - 3.5 keV). Together, the maps contain all ENAs within SARA/CENA's complete energy range (7 eV - 3.5 keV). The maps cover ~82% of the lunar surface, with almost complete coverage of the lunar farside. In the high energy part of the lunar ENA map several magnetic anomalies can be identified, whereas in the low energy part only the large magnetic anomaly associated with the South Pole-Aitken basin is clearly observed. By comparing SARA/CENA ENA maps to different lunar magnetic field maps, we found that they correlate better with the surface crustal magnetic field map than with the map showing the magnetic field at an altitude of 30 km. This implies that the main interaction between the solar wind plasma and the Moon occurs close to surface. Our high energy ENA map exhibits a strong anti-correlation with the map showing the flux of lunar deflected protons (Lue et al. [GRL 2011]) and appears to be an inverted image thereof. In addition, features in the ENA maps correlate with albedo features of swirls in the South Pole-Aitken basin. No obvious correlation with either the lunar topography or lunar geology map was found. The strength of ENA imaging together with ion reflection imaging lies in the fact that details of solar wind interaction with surfaces in the presence of electric and magnetic

  12. Vesta Mineralogy: VIR maps Vesta's surface

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

  13. Mapping surface disturbance from wind farms

    NASA Astrophysics Data System (ADS)

    Diffendorfer, James E.

    2013-04-01

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

  14. Compositional Mapping of Europa's Surface with SUDA

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  15. How to Map Space Weathering on an Asteroid Surface

    NASA Astrophysics Data System (ADS)

    Clark, B. E.; Barucci, M. A.; Merlin, F.; Lantz, C.; Campins, H.; Fornasier, S.; Dotto, E.; Lauretta, D. S.

    2015-11-01

    Our OSIRIS-REx space weathering map of asteroid 101955 Bennu will be an expression of the probability that each surface facet exhibits space weathering. To each surface facet, we will assign a ranking in: slope, band depth, albedo, and context.

  16. Brain surface maps from 3-D medical images

    NASA Astrophysics Data System (ADS)

    Lu, Jiuhuai; Hansen, Eric W.; Gazzaniga, Michael S.

    1991-06-01

    The anatomic and functional localization of brain lesions for neurologic diagnosis and brain surgery is facilitated by labeling the cortical surface in 3D images. This paper presents a method which extracts cortical contours from magnetic resonance (MR) image series and then produces a planar surface map which preserves important anatomic features. The resultant map may be used for manual anatomic localization as well as for further automatic labeling. Outer contours are determined on MR cross-sectional images by following the clear boundaries between gray matter and cerebral-spinal fluid, skipping over sulci. Carrying this contour below the surface by shrinking it along its normal produces an inner contour that alternately intercepts gray matter (sulci) and white matter along its length. This procedure is applied to every section in the set, and the image (grayscale) values along the inner contours are radially projected and interpolated onto a semi-cylindrical surface with axis normal to the slices and large enough to cover the whole brain. A planar map of the cortical surface results by flattening this cylindrical surface. The projection from inner contour to cylindrical surface is unique in the sense that different points on the inner contour correspond to different points on the cylindrical surface. As the outer contours are readily obtained by automatic segmentation, cortical maps can be made directly from an MR series.

  17. Mapping the surface charge distribution of amyloid fibril

    NASA Astrophysics Data System (ADS)

    Lee, Gyudo; Lee, Wonseok; Lee, Hyungbeen; Woo Lee, Sang; Sung Yoon, Dae; Eom, Kilho; Kwon, Taeyun

    2012-07-01

    It is of high importance to measure and map the surface charge distribution of amyloids, since electrostatic interaction between amyloidogenic proteins and biomolecules plays a vital role in amyloidogenesis. In this work, we have measured and mapped the surface charge distributions of amyloids (i.e., β-lactoglobulin fibril) using Kelvin probe force microscopy. It is shown that the surface charge distribution is highly dependent on the conformation of amyloids (e.g., the helical pitch of amyloid fibrils) as well as the pH of a solvent.

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

    USGS Publications Warehouse

    Hagens, A.; Doveton, J.H.

    1991-01-01

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

  19. [Ventricular activation sequence estimated by body surface isochrone map].

    PubMed

    Hayashi, H; Ishikawa, T; Takami, K; Kojima, H; Yabe, S; Ohsugi, S; Miyachi, K; Sotobata, I

    1985-06-01

    This study was performed to evaluate the usefulness of the body surface isochrone map (VAT map) for identifying the ventricular activation sequence, and it was correlated with the isopotential map. Subjects consisted of 42 normal healthy adults, 18 patients with artificial ventricular pacemakers, and 100 patients with ventricular premature beats (VPB). The sites of pacemaker implantations were the right ventricular endocardial apex (nine cases), right ventricular epicardial apex (five cases), right ventricular inflow tract (one case), left ventricular epicardial apex (one case), and posterior base of the left ventricle via the coronary sinus (two cases). An isopotential map was recorded by the mapper HPM-6500 (Chunichi-Denshi Co.) on the basis of an 87 unipolar lead ECG, and a VAT isochrone map was drawn by a minicomputer. The normal VAT map was classified by type according to alignment of isochrone lines, and their frequency was 57.1% for type A, 16.7% for type B, and 26.2% for type C. In the VAT map of ventricular pacing, the body surface area of initial isochrone lines represented well the sites of pacemaker stimuli. In the VAT map of VPB, the sites of origin of VPB agreed well with those as determined by the previous study using an isopotential map. The density of the isochrone lines suggested the mode of conduction via the specialized conduction system or ventricular muscle. The VAT map is a very useful diagnostic method to predict the ventricular activation sequence more directly in a single sheet of the map. PMID:2419457

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

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

  1. Monotone Sobolev Mappings of Planar Domains and Surfaces

    NASA Astrophysics Data System (ADS)

    Iwaniec, Tadeusz; Onninen, Jani

    2016-01-01

    An approximation theorem of Youngs (Duke Math J 15, 87-94, 1948) asserts that a continuous map between compact oriented topological 2-manifolds (surfaces) is monotone if and only if it is a uniform limit of homeomorphisms. Analogous approximation of Sobolev mappings is at the very heart of Geometric Function Theory (GFT) and Nonlinear Elasticity (NE). In both theories the mappings in question arise naturally as weak limits of energy-minimizing sequences of homeomorphisms. As a result of this, the energy-minimal mappings turn out to be monotone. In the present paper we show that, conversely, monotone mappings in the Sobolev space { {W}^{1,p} , 1 < p < ∞}, are none other than { {W}^{1,p} }-weak (also strong) limits of homeomorphisms. In fact, these are limits of diffeomorphisms. By way of illustration, we establish the existence of traction free energy-minimal deformations for p -harmonic type energy integrals.

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

    USGS Publications Warehouse

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

    2013-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Young, Eliot; Soderblom, Jason; Barnes, Jason

    2016-06-01

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

  4. Multi-Beam Surface Lidar for Lunar and Planetary Mapping

    NASA Technical Reports Server (NTRS)

    Bufton, Jack L.; Garvin, James B.

    1998-01-01

    Surface lidar techniques are now being demonstrated in low Earth orbit with a single beam of pulsed laser radiation at 1064 nm that profiles the vertical structure of Earth surface landforms along the nadir track of a spacecraft. In addition, a profiling laser altimeter, called MOLA, is operating in elliptical Martian orbit and returning surface topography data. These instruments form the basis for suggesting an improved lidar instrument that employs multiple beams for extension of sensor capabilities toward the goal of true, 3-dimensional mapping of the Moon or other similar planetary surfaces. In general the lidar waveform acquired with digitization of a laser echo can be used for laser distance measurement (i.e. range-to-the-surface) by time-of-flight measurement and for surface slope and shape measurements by examining the detailed lidar waveform. This is particularly effective when the intended target is the lunar surface or another planetary body free of any atmosphere. The width of the distorted return pulse is a first order measure of the surface incidence angle, a combination of surface slope and laser beam pointing. Assuming an independent and absolute (with respect to inertial space) measurement of laser beam pointing on the spacecraft, it is possible to derive a surface slope with-respect-to the mean planetary surface or its equipotential gravity surface. Higher-order laser pulse distortions can be interpreted in terms of the vertical relief of the surface or reflectivity variations within the area of the laser beam footprint on the surface.

  5. Morphology and surface mapping. [surface properties of lunar rocks

    NASA Technical Reports Server (NTRS)

    Marvin, U. B.

    1974-01-01

    Of the many boulders photographed at the Apollo 17 site, boulder 1 from Station 2 is unique in having a strongly developed foliation. Resistant layers form four steeply inclined ridges separated by joint planes or by deeply eroded beds of softer materials. A prominent cleavage, or set of cross joints, is oriented almost normal to the foliation. The cleavage is expressed as subparallel cracks, some of which are open fissures. The entire surface of the boulder is rough and studded by dark colored knobs ranging in diameter from 1 to 15 cm. It is a polymict breccia containing at least one type of rock that has not been recognized in any other lunar sample, and it records an unusual minor element distribution and magnetic history.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

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

    2016-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-08-01

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

  9. Surface-enhanced hyper-Raman and Raman hyperspectral mapping.

    PubMed

    Gühlke, Marina; Heiner, Zsuzsanna; Kneipp, Janina

    2016-06-01

    We investigate distributions of crystal violet and malachite green on plasmonic surfaces by principal component analysis (PCA) imaging of surface-enhanced hyper-Raman scattering (SEHRS) data. As a two-photon excited Raman scattering process, SEHRS provides chemical structure information based on molecular vibrations, but follows different selection rules than the normal, one-photon excited surface-enhanced Raman scattering (SERS). Therefore, simultaneous hyperspectral mapping using SEHRS excited at 1064 nm and SERS excited at 532 nm improves spatially resolved multivariate discrimination based on complementary vibrational information. The possibility to map distributions of the structurally similar dyes crystal violet and malachite green demonstrates the potential of this approach for multiplex imaging of complex systems. PMID:27166200

  10. Mapping global land surface albedo from NOAA AVHRR

    NASA Astrophysics Data System (ADS)

    Csiszar, I.; Gutman, G.

    1999-03-01

    A set of algorithms is combined for a simple derivation of land surface albedo from measurements of reflected visible and near-infrared radiation made by the advanced very high resolution radiometer (AVHRR) onboard the National Oceanic and Atmospheric Administration (NOAA) polar orbiting satellites. The system consists of a narrowband-to-broadband conversion and bidirectional correction at the top of the atmosphere and an atmospheric correction. We demonstrate the results with 1 month worth of data from the NOAA National Environmental Satellite, Data, and Information Service (NESDIS) global vegetation index (GVI) weekly data set and the NOAA/NASA Pathfinder Atmosphere (PATMOS) project daily data. Error analysis of the methodology indicates that the surface albedo can be retrieved with 10-15% relative accuracy. Monthly albedo maps derived from September 1989 GVI and PATMOS data agree well except for small discrepancies attributed mainly to different preprocessing and residual atmospheric effects. A 5-year mean September map derived from the GVI multiannual time series is consistent with that derived from low-resolution Earth Radiation Budget Experiment data as well as with a September map compiled from ground observations and used in many numerical weather and climate models. Instantaneous GVI-derived albedos were found to be consistent with surface albedo measurements over various surface types. The discrepancies found can be attributed to differences in areal coverage and representativeness of the satellite and ground data. The present pilot study is a prototype for a routine real-time production of high-resolution global surface albedo maps from NOAA AVHRR Global Area Coverage (GAC) data.

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

    SciTech Connect

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

    1992-11-01

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

  12. Robotic Radionuclide Inspection and Mapping of Surface Contamination On Building Surfaces

    SciTech Connect

    Mauer, G.F.; Kawa, Ch.

    2007-07-01

    The mapping of localized regions of radionuclide contamination in a building can be a time consuming and costly task. Humans moving hand-held radiation detectors over the target areas are subject to fatigue. A contamination map based on manual surveys can contain significant operator-induced inaccuracies. A Fanuc M16i light industrial robot has been configured for installation on a mobile aerial work platform, such as a tall forklift. When positioned in front of a surface, the robot can map the radiation levels over a surface area of up to 2 m by 2 m. The robot's end effector is a commercial alpha-beta radiation sensor, augmented with range and collision avoidance sensors to ensure operational safety as well as to maintain a constant gap between surface and radiation sensors. A graphical user interface guides the robot operator to position the robot at the desired wall segments, and to select an area for surveying. After the operator has entered the required parameters, the custom surveying software plans the scan sequence, alerts of any potential problems, such as unreachable singularities, and creates a contamination map of the surveyed region. Maps of multiple regions can be combined into a single map of the entire region. The survey data are stored in a data base file. In addition to automated surface scans, operators can manually select regions for further inspection, as well as control the end effector motion manually. In comparison to manual contamination surveys, the robotic approach is more accurate, reliable, and faster. (authors)

  13. Diffeomorphic Metric Surface Mapping in Superior Temporal Gyrus

    PubMed Central

    Vaillant, Marc; Qiu, Anqi; Glaunès, Joan; Miller, Michael I.

    2011-01-01

    This paper describes the application of large deformation diffeomorphic metric mapping to cortical surfaces based on the shape and geometric properties of subregions of the superior temporal gyrus in the human brain. The anatomical surfaces of the cortex are represented as triangulated meshes. The diffeomorphic matching algorithm is implemented by defining a norm between the triangulated meshes, based on the algorithms of Vaillant and Glaunès. The diffeomorphic correspondence is defined as a flow of the extrinsic three dimensional coordinates containing the cortical surface that registers the initial and target geometry by minimizing the norm. The methods are demonstrated in 40 high resolution MRI cortical surfaces of planum temporale (PT) constructed from subsets of the superior temporal gyrus (STG). The effectiveness of the algorithm is demonstrated via the Euclidean positional distance, distance of normal vectors, and curvature before and after the surface matching as well as the comparison with a landmark matching algorithm. The results demonstrate that both the positional and shape variability of the anatomical configurations are being represented by the diffeomorphic maps. PMID:17185000

  14. A desktop GIS approach to topographic mapping of surface saturation

    NASA Astrophysics Data System (ADS)

    Garroway, K.; Hopkinson, C.; Jamieson, R.; Boxall, J.

    2009-05-01

    Agricultural watersheds are generally highly modified environments. Accurately modelling topographic features in these environments can be difficult due to surface modifications inherent to agricultural practice, this was addressed by collecting high resolution topographic data. Airborne Laser Scanning (ALS) is a remote sensing technique whereby high resolution and high accuracy elevation data is collected throughout a landscape. In March of 2006 an ALS dataset was collected in the Thomas Brook Watershed located in Annapolis Valley, Nova Scotia. This data was collected over the watershed for high resolution modelling. Multiple topographic indices including topographic position index, topographic wetness index, slope gradient, curvature, and catchment area were modelled using 1m, 5m, and 10m DEM resolutions. The models were then compared to ground sampled soil surface moisture data that were collected during the 2006 and 2007 field seasons. A Student's T- test revealed that the topographic models agreed with the theories of surface wetness prediction, although the direct correlation between the models and the ground data was weak. A landform classification algorithm was augmented to incorporate the topographic models based on the theories of surface wetness prediction and a surface saturation map was generated. Tests revealed that the 5m DEM resolution yielded the most accurate results when compared directly to the surficial sampled surface moisture data. It was shown that the Surface Saturation Landform Classification algorithm can be used to predict zones of surface moisture throughout an agricultural watershed.

  15. Surface-based mapping of gene expression and probabilistic expression maps in the mouse cortex.

    PubMed

    Ng, Lydia; Lau, Chris; Sunkin, Susan M; Bernard, Amy; Chakravarty, M Mallar; Lein, Ed S; Jones, Allan R; Hawrylycz, Michael

    2010-02-01

    The Allen Brain Atlas (ABA, www.brain-map.org) is a genome wide, spatially registered collection of cellular resolution in situ hybridization gene expression image data of the C57Bl/6J mouse brain. Derived from the ABA, the Anatomic Gene Expression Atlas (AGEA, http://mouse.brain-map.org/agea) has demonstrated both laminar and areal spatial gene expression correlations in the mouse cortex. While the mouse cortex is lissencephalic, its curvature and substantial bending in boundary areas renders it difficult to visualize and analyze laminar versus areal effects in a rectilinear coordinate framework. In context of human and non-human primate cortex, surface-based representation has proven useful for understanding relative locations of laminar, columnar, and areal features. In this paper, we describe a methodology for constructing surface-based flatmaps of the mouse cortex that enables mapping of gene expression data from individual genes in the ABA, or probabilistic expression maps from the AGEA, to identify and visualize genetic relationships between layers and areas. PMID:19818854

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

    PubMed

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

    2012-09-20

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

  17. Probing and Mapping Electrode Surfaces in Solid Oxide Fuel Cells

    PubMed Central

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

    2012-01-01

    Solid oxide fuel cells (SOFCs) are potentially the most efficient and cost-effective solution to utilization of a wide variety of fuels beyond hydrogen 1-7. The performance of SOFCs and the rates of many chemical and energy transformation processes in energy storage and conversion devices in general are limited primarily by charge and mass transfer along electrode surfaces and across interfaces. Unfortunately, the mechanistic understanding of these processes is still lacking, due largely to the difficulty of characterizing these processes under in situ conditions. This knowledge gap is a chief obstacle to SOFC commercialization. The development of tools for probing and mapping surface chemistries relevant to electrode reactions is vital to unraveling the mechanisms of surface processes and to achieving rational design of new electrode materials for more efficient energy storage and conversion2. Among the relatively few in situ surface analysis methods, Raman spectroscopy can be performed even with high temperatures and harsh atmospheres, making it ideal for characterizing chemical processes relevant to SOFC anode performance and degradation8-12. It can also be used alongside electrochemical measurements, potentially allowing direct correlation of electrochemistry to surface chemistry in an operating cell. Proper in situ Raman mapping measurements would be useful for pin-pointing important anode reaction mechanisms because of its sensitivity to the relevant species, including anode performance degradation through carbon deposition8, 10, 13, 14 ("coking") and sulfur poisoning11, 15 and the manner in which surface modifications stave off this degradation16. The current work demonstrates significant progress towards this capability. In addition, the family of scanning probe microscopy (SPM) techniques provides a special approach to interrogate the electrode surface with nanoscale resolution. Besides the surface topography that is routinely collected by AFM and STM

  18. Mapping permeability over the surface of the Earth

    USGS Publications Warehouse

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

    2011-01-01

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

  19. Mapping permeability over the surface of the Earth

    USGS Publications Warehouse

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

    2011-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

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

  1. Mapping surface charge density with a scanning nanopipette

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

    Characterisation of the surface charge density (SCD) is important in interface and colloid science, and especially local variations in SCD of biological samples are of keen interest. The surface charge of lipid bilayers governs the uptake of charged particles and guides cell-cell interactions. As the electrostatic potential is screened by high physiological salt concentrations, direct probing of the potential can only be performed at a sub nanometer distance; therefore it was impossible to directly measure the SCD under physiological conditions. Yet the charged surface attracts counter ions leading to an enhanced ionic concentration near the surface, creating a measurable surface conductivity. In this study we measure SCD using a scanning ion-conductance microscope (SICM) setup, where the electrolyte current through a nanopipette is monitored as the pipette is positioned in the vicinity of the sample. We investigate the current dependency of SCD and pipette potential using numerical solutions to Poisson and Nernst-Planck equations and characterise a complex system governed by a multitude of factors such as pipette size, geometry and charge. We then propose an imaging method and prove its feasibility by mapping the surface charge density of phase separated lipid bilayers.

  2. [Mapping sensitivity of surface waters to acidification in China].

    PubMed

    Ye, Xuemei; Hao, Jiming; Duan, Lei; Zhou, Zhongping

    2002-01-30

    Acidification of surface waters can be decided by some environmental factors, such as soil's buffering capacity, neutralization capacity of bedrock to acid deposition and types of land use, among which the most important factor is the soil's resistance to acidification. Therefore, information about soils, geology and land use can be used to predict the regional occurrence of acidification surface waters under different flows. In this paper, information and data about Chinese soils, geology and land use types were collected to determine and to map the sensitivity of surface waters to acidification. Results showed that in China, most surface waters were not sensitive to acidification. The few most sensitive surface waters were located in the north part of Northeastern China, accounting for 2.67% of all the country land. It was the combined results of strongly acidified ortho podzolic soil, acidified bedrock and coniferous forest. Surface waters which were not very sensitive to acidification were distributed both in the region of dark brown forest soil in Northeastern China and in the ferralsol and yellow-brown earth area in Southern China, occupying 15.2% of all the country land. The other surface waters which distributed on 82.11% of all the country land were not sensitive to acidification at all. Most in the Northern China because of the high resistance of soils to acidification and the others were in the Southern China where calcareous soils and agricultural lands were widely distributed. Since soils were quite resistant to acid, acidification of surface waters of large area will not likely occur in the southern region of China suffering from heavy acid deposition in the near future. Nevertheless, the acid deposition in Northern China should be controlled as soon as possible in case that acidified surface waters will be found there.

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

    USGS Publications Warehouse

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

    1998-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  5. SMOS sea surface salinity maps of the Arctic Ocean

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  6. Raman mapping of intact biofilms on stainless steel surfaces

    NASA Astrophysics Data System (ADS)

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

    2016-05-01

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

  7. Surface Towed CSEM Systems for Shallow Water Mapping

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  8. CosmoQuest: A software platform for surface feature mapping

    NASA Astrophysics Data System (ADS)

    Gay, Pamela

    2016-07-01

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

  9. Mapping cardiac surface mechanics with structured light imaging

    PubMed Central

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

    2012-01-01

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

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

    PubMed

    Voronovich, Alexander G; Penland, Cécile

    2011-05-01

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

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

    USGS Publications Warehouse

    Leake, Stanley A.

    2006-01-01

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

  12. Local cortical surface complexity maps from spherical harmonic reconstructions.

    PubMed

    Yotter, Rachel A; Nenadic, Igor; Ziegler, Gabriel; Thompson, Paul M; Gaser, Christian

    2011-06-01

    Altered cortical surface complexity and gyrification differences may be a potentially sensitive marker for several neurodevelopmental disorders. We propose to use spherical harmonic (SPH) constructions to measure cortical surface folding complexity. First, we demonstrate that the complexity measure is accurate, by applying our SPH approach and the more traditional box-counting method to von Koch fractal surfaces with known fractal dimension (FD) values. The SPH approach is then applied to study complexity differences between 87 patients with DSM-IV schizophrenia (with stable psychopathology and treated with antipsychotic medication; 48 male/39 female; mean age=35.5 years, SD=11.0) and 108 matched healthy controls (68 male/40 female; mean age=32.1 years, SD=10.0). The global FD for the right hemisphere in the schizophrenia group was significantly reduced. Regionally, reduced complexity was also found in temporal, frontal, and cingulate regions in the right hemisphere, and temporal and prefrontal regions in the left hemisphere. These results are discussed in terms of previously published findings. Finally, the anatomical implications of a reduced FD are highlighted through comparison of two subjects with vastly different complexity maps.

  13. Heat capacity mapping mission. [satellite for earth surface temperature measurement

    NASA Technical Reports Server (NTRS)

    Price, J. C.

    1978-01-01

    A Heat Capacity Mapping Mission (HCMM), part of a series of Applications Explorers Missions, is designed to provide data on surface heating as a response to solar energy input. The data is obtained by a two channel scanning radiometer, with one channel covering the visible and near-IR band between 0.5 and 1.1 micrometers, and the other covering the thermal-IR between 10.5 and 12.5 micrometers. The temperature range covered lies between 260 and 340 K, in 0.3 deg steps, with an accuracy at 280 K of plus or minus 0.5 K. Nominal altitude is 620 km, with a ground swath 700 km wide.

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

    NASA Astrophysics Data System (ADS)

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

    2016-05-01

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

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

    USGS Publications Warehouse

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

    1993-01-01

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

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

    SciTech Connect

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

    1994-12-01

    The revised potentiometric-surface map presented in this report updates earlier maps of the Yucca Mountain area using mainly 1988 average water levels. Because of refinements in the corrections to the water-level measurements, these water levels have increased accuracy and precision over older values. The small-gradient area to the southeast of Yucca Mountain is contoured with a 0.25-meter interval and ranges in water-level altitude from 728.5 to 73 1.0 meters. Other areas with different water levels, to the north and west of Yucca Mountain, are illustrated with shaded patterns. The potentiometric surface can be divided into three regions: (1) A small-gradient area to the southeast of Yucca Mountain, which may be explained by flow through high-transmissivity rocks or low ground-water flux through the area; (2) A moderate-gradient area, on the western side of Yucca Mountain, where the water-level altitude ranges from 775 to 780 meters, and appears to be impeded by the Solitario Canyon Fault and a splay of that fault; and (3) A large-gradient area, to the north-northeast of Yucca Mountain, where water level altitude ranges from 738 to 1,035 meters, possibly as a result of a semi-perched groundwater system. Water levels from wells at Yucca Mountain were examined for yearly trends using linear least-squares regression. Data from five wells exhibited trends which were statistically significant, but some of those may be a result of slow equilibration of the water level from drilling in less permeable rocks. Adjustments for temperature and density changes in the deep wells with long fluid columns were attempted, but some of the adjusted data did not fit the surrounding data and, thus, were not used.

  17. Deformable structure registration of bladder through surface mapping.

    PubMed

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

    2006-06-01

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

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

    SciTech Connect

    Reedy, R.C.

    1990-01-01

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

  19. Mapping photosynthetically available radiation at the sea surface using GOCI

    NASA Astrophysics Data System (ADS)

    Choi, Jongkuk; Kim, Jihye; Yang, Hyun; Moon, Jeong-Eon; Frouin, Robert

    2016-04-01

    Photosynthetically available radiation (PAR) controls the composition of marine ecosystem by affecting the growth of phytoplankton, thus estimating PAR at the ocean surface accurately is important to understand the marine ecological environment. Although many studies have been attempted to estimate PAR employing ocean colour satellite data since 2003, previous studies using data from the polar orbit systems had spatial and temporal limitations to estimate accurate daily PAR. Here, we estimate daily PAR from Geostationary Ocean Colour Imager (GOCI) which collects data eight times a day at an hour interval in daytime and compare it with in-situ measurement and MODIS-based daily PAR. The algorithm we developed in this study, employed GOCI visible bands (centred at (412, 443, 490, 555, 660, 680 nm) which belongs to the range of PAR by calculating albedo at the layer of clouds and the sea surface to estimate daily PAR. The resultant value was validated by comparing the in-situ measurements acquired from an ocean research station, Socheongcho between February and May 2015, which showed a similar pattern with somewhat GOCI-base PAR's overestimations. The comparison with the results from MODIS, a polar orbit system showed that a good agreement with each other was illustrated at clear sky conditions, while MODIS showed some over- or underestimations at cloudy conditions with irregular patterns. This study shows that GOCI can estimate effectively the daily PAR with its advantages of acquiring data more frequently than other polar orbit ocean colour satellites by reducing the uncertainties induced by insufficient images to map the daily PAR at ocean surface.

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

    PubMed Central

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

    2007-01-01

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

  1. Cancer Risk Map for the Surface of Mars

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Cohen, Barbara A.

    2014-01-01

    Lunar Flashlight is an exciting new mission concept in preformulation studies for NASA's Advanced Exploration Systems (AES) by a team from the Jet Propulsion Laboratory, UCLA, and Marshall Space Flight Center. This innovative, low-cost concept will map the lunar south pole for volatiles and demonstrate several technological firsts, including being the first CubeSat to reach the Moon, the first mission to use an 80 m2 solar sail, and the first mission to use a solar sail as a reflector for science observations. The Lunar Flashlight mission spacecraft maneuvers to its lunar polar orbit and uses its solar sail as a mirror to reflect 50 kW of sunlight down into shaded polar regions, while the on-board spectrometer measures surface reflection and composition. The Lunar Flashlight 6U spacecraft has heritage elements from multiple cubesat systems. The deployable solar sail/reflector is based on previous solar sail experiments, scaled up for this mission. The mission will demonstrate a path where 6U CubeSats could, at dramatically lower cost than previously thought possible, explore, locate and estimate size and composition of ice deposits on the Moon. Locating ice deposits in the Moon's permanently shadowed craters addresses one of NASA's Strategic Knowledge Gaps (SKGs) to detect composition, quantity, distribution, form of water/H species and other volatiles associated with lunar cold traps. Polar volatile data collected by Lunar Flashlight could then ensure that targets for more expensive lander- and rover-borne measurements would include volatiles in sufficient quantity and near enough to the surface to be operationally useful.

  3. Sub-surface minority carrier lifetime mapping in photovoltaic materials

    NASA Astrophysics Data System (ADS)

    Schuck, P. James

    2014-03-01

    The minority carrier lifetime is considered one of the most critical and variable parameters in photovoltaic materials. However, accurately measuring its value is one of the great challenges in evaluating unconventional semiconductor materials for PV applications. I will describe our two-photon time-resolved photoluminescence decay measurements, which allow us to decouple surface and bulk recombination processes even in unpassivated samples. We demonstrate how the traditional one-photon technique can underestimate the bulk lifetime in a CdTe crystal by 10X and show that two-photon excitation more-accurately measures the bulk lifetime. I will finish by discussing how this technique enables the generation of three-dimensional minority carrier lifetime and charge collection efficiency maps that will be useful in identifying efficiency bottlenecks for new and conventional (e.g. CdTe & CIGS) thin film PV materials. Other Authors: Edward S. Barnard1, Eric T. Hoke2, Shaul Aloni1, Craig H. Peters2, Brian E. Hardin2; 1 The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley CA; 2 PLANT PV Inc. Oakland CA.

  4. Navigating the airport surface: Electronic vs. paper maps

    NASA Technical Reports Server (NTRS)

    Batson, Vernon M.; Harris, Randall L., Sr.; Hunt, Patricia J.

    1994-01-01

    Recent advances in the Differential Global Positioning System (DGPS) and ground/aircraft data-links provide a basis for the generation of an accurate cockpit navigational map display including data-linked ATC-cleared ground routes. Such an electronic map may have the potential to improve pilots' situation awareness and taxi performance and thereby lessen runway incursions. The objective of this simulator study was to assess the potential improvements in these areas when using an advanced electronic map (compared to using today's paper map) under two outside scene visibility levels. Results showed average taxi speed increased under both good and poor visibilities, by as much as 24 percent, due in part to eliminating the time used for orientation with the paper map. Pilots made only one-third as many errors as well and commented that they believed that the electronic map gave them better awareness.

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

    NASA Technical Reports Server (NTRS)

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

    2014-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

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

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

    SciTech Connect

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

    1991-04-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

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

  10. Mapping Resources Potential of the Lunar Surface for Human Exploration

    NASA Astrophysics Data System (ADS)

    Garvin, James

    2005-07-01

    We propose to use the ACS/HRC to delineate UV through visible color units at three test sites on the lunar surface for the purpose of identifying localized areas enriched in potential resources, including TiO2. This pathfinding experiment will make use of HST's unique high resolution imaging capabilities in the near UV. We will observe the Apollo 15 and 17 sites to establish an empirical calibration against sampled lunar soils. We will then observe the Aristarchus Plateau in search of regions enriched in TiO2 at levels that could permit in situ resources utilization activities that support sustained human exploration. Precision mapping of TiO2 abundance and other chemical proxies by virtue of HST's high angular resolution in near UV wavelengths will extend lower resolution Visible-NIR results obtained from orbit by Clementine, and set the stage for future orbital surveys later in the decade. Understanding whether there are lunar near-side sites with adequate resource potential to target human "sorties" and related robotic precursor missions represents an important decision point in NASA's implementation of the President's Vision for Space Exploration. The proposed HST ACS/HRC test data directly support near-term engineering trades associated with the optimal location for the first human return missions to the Moon. No past, current, or planned future lunar orbiting spacecraft will have the ability to investigate the near UV aspects of the lunar spectrum at such scales { 50m}, so the results of the proposed HST observations are unique and relevant to NASA's mission.

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

    NASA Technical Reports Server (NTRS)

    Sidick, Erkin

    2012-01-01

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

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

    SciTech Connect

    Bechtel Nevada

    2005-08-01

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

  13. Note: Molecular diffusivity in a small pore zeolite measured by a variable pressure (piezometric) uptake method

    NASA Astrophysics Data System (ADS)

    Wang, Fei; Kobayashi, Yasukazu; Muhammad, Usman; Wang, Dezheng; Wang, Yao

    2016-03-01

    The use of numerical analysis to solve the diffusion equation in the uptake method allowed the measurement of molecular diffusivity in a zeolite with a variable pressure around it. The diffusivity was obtained from the data in the measurement of the adsorption isotherm, which means that the diffusivity measurement now needs neither a special instrument nor procedure. The diffusivities of all the gases are readily available from the measurement of their adsorption isotherms and these data include how the diffusivity changes versus adsorbed concentration. The modeling introduced can also be used for a zeolite with a surface barrier.

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

    NASA Technical Reports Server (NTRS)

    Paine, Jeffery G.

    2003-01-01

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

  15. Ray mapping approach for the efficient design of continuous freeform surfaces.

    PubMed

    Bösel, Christoph; Gross, Herbert

    2016-06-27

    The efficient design of continuous freeform surfaces, which maps a given light source to an arbitrary target illumination pattern, remains a challenging problem and is considered here for collimated input beams. A common approach are ray-mapping methods, where first a ray mapping between the source and the irradiance distribution on the target plane is calculated and in a subsequent step the surface is constructed. The challenging aspect of this approach is to find an integrable mapping ensuring a continuous surface. Based on the law of reflection/refraction and an integrability condition, we derive a general condition for the surface and ray mapping for a collimated input beam. It is shown that in a small-angle approximation a proper mapping can be calculated via optimal mass transport - a mathematical framework for the calculation of a mapping between two positive density functions. We show that the surface can be constructed by solving a linear advection Eq. with appropriate boundary conditions. The results imply that the optimal mass transport mapping is approximately integrable over a wide range of distances between the freeform and the target plane and offer an efficient way to construct the surface by solving standard integrals. The efficiency is demonstrated by applying it to two challenging design examples, which shows the ability of the presented approach to handle target illumination patterns with steep irradiance gradients and numerous gray levels. PMID:27410583

  16. Mapping

    ERIC Educational Resources Information Center

    Kinney, Douglas M.; McIntosh, Willard L.

    1978-01-01

    Geologic mapping in the United States increased by about one-quarter in the past year. Examinations of mapping trends were in the following categories: (1) Mapping at scales of 1:100, 000; (2) Metric-scale base maps; (3) International mapping, and (4) Planetary mapping. (MA)

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

    SciTech Connect

    Bechtel Nevada

    2005-08-01

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

  18. Surface and atmosphere parameter maps from earth-orbiting radiometers

    NASA Technical Reports Server (NTRS)

    Gloersen, P.

    1976-01-01

    Earlier studies have shown that an earth-orbiting electrically scanned microwave radiometer (ESMR) is capable of inferring the extent, concentration, and age of sea ice; the extent, concentration, and thickness of lake ice; rainfall rates over oceans; surface wind speeds over open water; particle size distribution in the deep snow cover of continental ice sheets; and soil moisture content in unvegetated fields. Most other features of the surface of the earth and its atmosphere require multispectral imaging techniques to unscramble the combined contributions of the atmosphere and the surface. Multispectral extraction of surface parameters is analyzed on the basis of a pertinent equation in terms of the observed brightness temperature, the emissivity of the surface which depends on wavelength and various parameters, the sensible temperature of the surface, and the total atmospheric opacity which is also wavelength dependent. Implementation of the multispectral technique is examined. Properties of the surface of the earth and its atmosphere to be determined from a scanning multichannel microwave radiometer are tabulated.

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

    NASA Technical Reports Server (NTRS)

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

    1998-01-01

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

  20. Functional and structural mapping of human cerebral cortex: Solutions are in the surfaces

    PubMed Central

    Van Essen, David C.; Drury, Heather A.; Joshi, Sarang; Miller, Michael I.

    1998-01-01

    The human cerebral cortex is notorious for the depth and irregularity of its convolutions and for its variability from one individual to the next. These complexities of cortical geography have been a chronic impediment to studies of functional specialization in the cortex. In this report, we discuss ways to compensate for the convolutions by using a combination of strategies whose common denominator involves explicit reconstructions of the cortical surface. Surface-based visualization involves reconstructing cortical surfaces and displaying them, along with associated experimental data, in various complementary formats (including three-dimensional native configurations, two-dimensional slices, extensively smoothed surfaces, ellipsoidal representations, and cortical flat maps). Generating these representations for the cortex of the Visible Man leads to a surface-based atlas that has important advantages over conventional stereotaxic atlases as a substrate for displaying and analyzing large amounts of experimental data. We illustrate this by showing the relationship between functionally specialized regions and topographically organized areas in human visual cortex. Surface-based warping allows data to be mapped from individual hemispheres to a surface-based atlas while respecting surface topology, improving registration of identifiable landmarks, and minimizing unwanted distortions. Surface-based warping also can aid in comparisons between species, which we illustrate by warping a macaque flat map to match the shape of a human flat map. Collectively, these approaches will allow more refined analyses of commonalities as well as individual differences in the functional organization of primate cerebral cortex. PMID:9448242

  1. Surface Emissivity Maps for Satellite Retrieval of the Longwave Radiation Budget

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

    This paper presents a brief description of the procedure used to produce global surface emissivity maps for the broadband LW, the 8-12 micrometer window, and 12 narrow LW bands. For a detailed description of the methodology and the input data, the reader is referred to Wilber et al. (1999). These maps are based on a time-independent surface type map published by the IGBP, and laboratory measurements of spectral reflectances of surface materials. These maps represent a first attempt to characterize emissivity based on surface types, and many improvements to the methodology presented here are already underway. Effects of viewing zenith angle and sea state on the emissivity of ocean surface (Smith et al. 1996, Wu and Smith 1997, Masuda et al. 1988) will be taken into account. Measurements form ASTER and MODIS will be incorporated as they become available. Seasonal variation of emissivity based on changes in the characteristics of vegetation will be considered, and the variability of emissivity of barren land areas will be accounted for with the use of Zobler World Soil Maps (Zobler 1986). The current maps have been made available to the scientific community from the web site: http://tanalo.larc.nasa.gov:8080/surf_htmls/ SARB_surf.html

  2. Optical and electrical mappings of surface plasmon cavity modes

    NASA Astrophysics Data System (ADS)

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

    2014-04-01

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

  3. Mapping Surface Temperature on Biological Tissues by Infrared Thermography

    NASA Astrophysics Data System (ADS)

    Gnyawali, Surya; Chen, Yichao; Bartels, Kenneth; Wicksted, James; Chen, Wei

    2007-03-01

    In this paper, non-contact and noninvasive infrared thermography in the measurement of skin temperature on a mice model during dye-enhanced laser-tumor treatment coupled with the immunological response is explored. Mice with mammary tumors are injected with light absorption enhancing dye (indocyanine green, ICG) and immunoadjuvant (glycated chitosan, GC) prior to laser light (805 nm) irradiation through optical fiber. Using an infrared temperature probe, images are acquired and analyzed to determine surface temperature measurements. Simulations of the surface temperature measurements are conducted using a Monte Carlo finite difference method. The simulation results are in good agreement with the thermography measurements.

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

    NASA Technical Reports Server (NTRS)

    Sidick, Erkin

    2012-01-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    USGS Publications Warehouse

    Falcone, J.A.; Gomez, R.

    2005-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2012-01-01

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

  8. Multispectral mapping of the lunar surface using groundbased telescopes

    NASA Technical Reports Server (NTRS)

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

    1976-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Fu, Lee-Lueng; Rodriquez, Ernesto

    2006-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Spruce, Joe; Berglund, Judith; Davis, Bruce

    2006-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

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

  12. Comet 67P: surface temperature maps as derived by Rosetta/VIRTIS in the early Mapping phase

    NASA Astrophysics Data System (ADS)

    Tosi, Federico; Capria, Maria Teresa; Capaccioni, Fabrizio; Filacchione, Gianrico; De Sanctis, Maria Cristina; Erard, Stéphane; Leyrat, Cedric; Bockelee-Morvan, Dominique; Kuehrt, Ekkehard

    2014-11-01

    We show spatially-resolved temperature maps of comet 67P/Churyumov-Gerasimenko, main target of the ESA Rosetta spacecraft, as obtained from infrared hyperspectral images acquired by the VIRTIS imaging spectrometer onboard the Rosetta Orbiter in the early Mapping phase carried out in August 2014.VIRTIS infrared spectra in the range longward of about 4 μm are affected by the thermal emission of the comet, hence the measured radiance in that spectral region can be used to determine surface temperatures and spectral emissivities by means of temperature-retrieval algorithms.The VIRTIS instrument onboard Rosetta is not sensitive to physical temperatures on the nightside of the comet, where the signal is considerably low. Typically, ~170 K is the minimum temperature that allows one to retrieve surface temperatures while preserving small formal errors (<1 K on retrieved temperatures). On the other hand, for a given local solar time (LST), the maximum temperature depends on the solar incidence angle and on surface properties such as thermal inertia and albedo.Here we show surface temperature maps of comet 67P at a spatial resolution of 20-25 m/px, and under variable phase angles, illumination conditions, and heliocentric distances (spanning the range from 3.62 to 3.45 AU). We focus both on regional maps and on peculiar sites of interest seen at the local scale, with a special emphasis on the expected location of the landing site.The availability of spatially-resolved, accurate temperature observations, significantly spaced out in local solar time, provides clues to the physical structure of specific surface units, which complements the mineralogical investigation based on imaging spectroscopy data collected at shorter wavelengths.AcknowledgementsThis work is supported by the Italian Space Agency (ASI), ASI-INAF Contract n. I/024/12/0. We acknowledge funding from the French Space Agency (CNES) and the German Aerospace Center (DLR). Support of the Rosetta and VIRTIS Science

  13. Mapping.

    ERIC Educational Resources Information Center

    Kinney, Douglas M.; McIntosh, Willard L.

    1979-01-01

    The area of geological mapping in the United States in 1978 increased greatly over that reported in 1977; state geological maps were added for California, Idaho, Nevada, and Alaska last year. (Author/BB)

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

    SciTech Connect

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

    1992-10-01

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

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

    SciTech Connect

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

    1992-10-01

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

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

    USGS Publications Warehouse

    Haeussler, Peter J.

    2009-01-01

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

  17. Near-field mapping of three-dimensional surface charge poles for hybridized plasmon modes

    NASA Astrophysics Data System (ADS)

    Huang, Yu; Ringe, Emilie; Hou, Mengjing; Ma, Lingwei; Zhang, Zhengjun

    2015-10-01

    We describe a new computational approach to mapping three-dimensional (3D) surface charge poles and thus to determine complicated and hybridized plasmon modes in metallic nanostructures via finite element method (FEM) calculations. 3D surface charge distributions at the near-field resonance energies are calculated directly using Gauss' law. For a nanosphere dimer, we demonstrate that higher-order hybridized plasmon modes can be addressed clearly. As an improvement to conventional mapping approaches, this new approach provides a better understanding of comprehensive physical image of plasmonic systems necessary for fundamental studies and spectroscopy applications.

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

    NASA Technical Reports Server (NTRS)

    Anderson, Eric

    2016-01-01

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

  19. Effect of surface topography in the generation of chemical maps by laser-induced plasma spectroscopy

    NASA Astrophysics Data System (ADS)

    Lopez-Quintas, I.; Piñon, V.; Mateo, M. P.; Nicolas, G.

    2012-09-01

    The development of technologically advanced materials is propelling the improvement of surface analytical techniques. In particular, the composition and hence the properties of most of these new materials are spatial dependent. Between the techniques able to provide chemical spatial information, laser-induced plasma spectroscopy known also as laser-induced breakdown spectroscopy (LIBS) is a very promising analytical technique. During the last decade, LIBS was successfully applied to the analysis of surfaces and the generation of chemical maps of heterogeneous materials. In the LIBS analysis, several experimental factors including surface topography must be taken into account. In this work, the influence of surface roughness in LIBS signal during the point analysis and acquisition of chemical maps was studied. For this purpose, samples of stainless steel with different surface finishes were prepared and analyzed by LIBS. In order to characterize the different surfaces, confocal microscopy images were obtained. Afterwards, both topographic and spectroscopic information were combined to show the relationship between them. Additionally, in order to reveal the effect of surface topography in the acquisition of chemical maps, a three dimensional analysis of a sample exhibiting two different finishes was carried out.

  20. Characterizing arid region alluvial fan surface roughness with airborne laser swath mapping digital topographic data

    NASA Astrophysics Data System (ADS)

    Frankel, Kurt L.; Dolan, James F.

    2007-06-01

    Range-front alluvial fan deposition in arid environments is episodic and results in multiple fan surfaces and ages. These distinct landforms are often defined by descriptions of their surface morphology, desert varnish accumulation, clast rubification, desert pavement formation, soil development, and stratigraphy. Although quantifying surface roughness differences between alluvial fan units has proven to be difficult in the past, high-resolution airborne laser swath mapping (ALSM) digital topographic data are now providing researchers with an opportunity to study topography in unprecedented detail. Here we use ALSM data to calculate surface roughness on two alluvial fans in northern Death Valley, California. We define surface roughness as the standard deviation of slope in a 5-m by 5-m moving window. Comparison of surface roughness values between mapped fan surfaces shows that each unit is statistically unique at the 99% confidence level. Furthermore, there is an obvious smoothing trend from the presently active channel to a deposit with cosmogenic 10Be and 36Cl surface exposure ages of ˜70 ka. Beyond 70 ka, alluvial landforms become progressively rougher with age. These data suggest that alluvial fans in arid regions smooth out with time until a threshold is crossed where roughness increases at greater wavelength with age as a result of surface runoff and headward tributary incision into the oldest surfaces.

  1. Occupancy mapping and surface reconstruction using local Gaussian processes with Kinect sensors.

    PubMed

    Kim, Soohwan; Kim, Jonghyuk

    2013-10-01

    Although RGB-D sensors have been successfully applied to visual SLAM and surface reconstruction, most of the applications aim at visualization. In this paper, we propose a noble method of building continuous occupancy maps and reconstructing surfaces in a single framework for both navigation and visualization. Particularly, we apply a Bayesian nonparametric approach, Gaussian process classification, to occupancy mapping. However, it suffers from high-computational complexity of O(n(3))+O(n(2)m), where n and m are the numbers of training and test data, respectively, limiting its use for large-scale mapping with huge training data, which is common with high-resolution RGB-D sensors. Therefore, we partition both training and test data with a coarse-to-fine clustering method and apply Gaussian processes to each local clusters. In addition, we consider Gaussian processes as implicit functions, and thus extract iso-surfaces from the scalar fields, continuous occupancy maps, using marching cubes. By doing that, we are able to build two types of map representations within a single framework of Gaussian processes. Experimental results with 2-D simulated data show that the accuracy of our approximated method is comparable to previous work, while the computational time is dramatically reduced. We also demonstrate our method with 3-D real data to show its feasibility in large-scale environments. PMID:23893758

  2. Mapping lipid and detergent molecules at the surface of membrane proteins.

    PubMed

    Cogdell, Richard J; Gardiner, Alastair T; Roszak, Aleksander W; Stončius, Sigitas; Kočovský, Pavel; Isaacs, Neil W

    2011-06-01

    Electron-density maps for the crystal structures of membrane proteins often show features suggesting binding of lipids and/or detergent molecules on the hydrophobic surface, but usually it is difficult to identify the bound molecules. In our studies, heavy-atom-labelled phospholipids and detergents have been used to unequivocally identify these binding sites at the surfaces of test membrane proteins, the reaction centres from Rhodobacter sphaeroides and Blastochloris viridis. The generality of this method is discussed in the present article.

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

    USGS Publications Warehouse

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

    2016-01-01

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

  4. Large Deformation Multiresolution Diffeomorphic Metric Mapping for Multiresolution Cortical Surfaces: A Coarse-to-Fine Approach.

    PubMed

    Tan, Mingzhen; Qiu, Anqi

    2016-09-01

    Brain surface registration is an important tool for characterizing cortical anatomical variations and understanding their roles in normal cortical development and psychiatric diseases. However, surface registration remains challenging due to complicated cortical anatomy and its large differences across individuals. In this paper, we propose a fast coarse-to-fine algorithm for surface registration by adapting the large diffeomorphic deformation metric mapping (LDDMM) framework for surface mapping and show improvements in speed and accuracy via a multiresolution analysis of surface meshes and the construction of multiresolution diffeomorphic transformations. The proposed method constructs a family of multiresolution meshes that are used as natural sparse priors of the cortical morphology. At varying resolutions, these meshes act as anchor points where the parameterization of multiresolution deformation vector fields can be supported, allowing the construction of a bundle of multiresolution deformation fields, each originating from a different resolution. Using a coarse-to-fine approach, we show a potential reduction in computation cost along with improvements in sulcal alignment when compared with LDDMM surface mapping. PMID:27254865

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

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2005-01-01

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

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

    PubMed

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

    2015-01-01

    Numerous studies have investigated the direct retrieval of soil properties, including soil texture, using remotely sensed images. However, few have considered how soil properties influence dynamic changes in remote images or how soil processes affect the characteristics of the spectrum. This study investigated a new method for mapping regional soil texture based on the hypothesis that the rate of change of land surface temperature is related to soil texture, given the assumption of similar starting soil moisture conditions. The study area was a typical flat area in the Yangtze-Huai River Plain, East China. We used the widely available land surface temperature product of MODIS as the main data source. We analyzed the relationships between the content of different particle soil size fractions at the soil surface and land surface day temperature, night temperature and diurnal temperature range (DTR) during three selected time periods. These periods occurred after rainfalls and between the previous harvest and the subsequent autumn sowing in 2004, 2007 and 2008. Then, linear regression models were developed between the land surface DTR and sand (> 0.05 mm), clay (< 0.001 mm) and physical clay (< 0.01 mm) contents. The models for each day were used to estimate soil texture. The spatial distribution of soil texture from the studied area was mapped based on the model with the minimum RMSE. A validation dataset produced error estimates for the predicted maps of sand, clay and physical clay, expressed as RMSE of 10.69%, 4.57%, and 12.99%, respectively. The absolute error of the predictions is largely influenced by variations in land cover. Additionally, the maps produced by the models illustrate the natural spatial continuity of soil texture. This study demonstrates the potential for digitally mapping regional soil texture variations in flat areas using readily available MODIS data. PMID:26090852

  8. Mapping Carrier Dynamics on Material Surfaces in Space and Time using Scanning Ultrafast Electron Microscopy.

    PubMed

    Sun, Jingya; Adhikari, Aniruddha; Shaheen, Basamat S; Yang, Haoze; Mohammed, Omar F

    2016-03-17

    Selectively capturing the ultrafast dynamics of charge carriers on materials surfaces and at interfaces is crucial to the design of solar cells and optoelectronic devices. Despite extensive research efforts over the past few decades, information and understanding about surface-dynamical processes, including carrier trapping and recombination remains extremely limited. A key challenge is to selectively map such dynamic processes, a capability that is hitherto impractical by time-resolved laser techniques, which are limited by the laser's relatively large penetration depth and consequently these techniques record mainly bulk information. Such surface dynamics can only be mapped in real space and time by applying four-dimensional (4D) scanning ultrafast electron microscopy (S-UEM), which records snapshots of materials surfaces with nanometer spatial and subpicosecond temporal resolutions. In this method, the secondary electron (SE) signal emitted from the sample's surface is extremely sensitive to the surface dynamics and is detected in real time. In several unique applications, we spatially and temporally visualize the SE energy gain and loss, the charge carrier dynamics on the surface of InGaN nanowires and CdSe single crystal and its powder film. We also discuss the mechanisms for the observed dynamics, which will be the foundation for future potential applications of S-UEM to a wide range of studies on material surfaces and device interfaces.

  9. Globalland30 Mapping Capacity of Land Surface Water in Thessaly, Greece

    NASA Astrophysics Data System (ADS)

    Manakos, Ioannis; Chatzopoulos-Vouzoglanis, Konstantinos; Petrou, Zisis I.; Filchev, Lachezar; Apostolakis, Antonis

    2015-01-01

    The National Geomatics Center of China (NGCC) produced Global Land Cover (GlobalLand30) maps with 30 m spatial resolution for the years 2000 and 2009-2010, responding to the need for harmonized, accurate, and high-resolution global land cover data. This study aims to assess the mapping accuracy of the land surface water layer of GlobalLand30 for 2009-2010. A representative Mediterranean region, situated in Greece, is considered as the case study area, with 2009 as the reference year. The assessment is realized through an object-based comparison of the GlobalLand30 water layer with the ground truth and visually interpreted data from the Hellenic Cadastre fine spatial resolution (0.5 m) orthophoto map layer. GlobCover 2009, GlobCorine 2009, and GLCNMO 2008 corresponding thematic layers are utilized to show and quantify the progress brought along with the increment of the spatial resolution, from 500 m to 300 m and finally to 30 m with the newly produced GlobalLand30 maps. GlobalLand30 detected land surface water areas show a 91.9% overlap with the reference data, while the coarser resolution products are restricted to lower accuracies. Validation is extended to the drainage network elements, i.e., rivers and streams, where GlobalLand30 outperforms the other global map products, as well.

  10. A triangulation-invariant method for anisotropic geodesic map computation on surface meshes.

    PubMed

    Yoo, Sang Wook; Seong, Joon-Kyung; Sung, Min-Hyuk; Shin, Sung Yo; Cohen, Elaine

    2012-10-01

    This paper addresses the problem of computing the geodesic distance map from a given set of source vertices to all other vertices on a surface mesh using an anisotropic distance metric. Formulating this problem as an equivalent control theoretic problem with Hamilton-Jacobi-Bellman partial differential equations, we present a framework for computing an anisotropic geodesic map using a curvature-based speed function. An ordered upwind method (OUM)-based solver for these equations is available for unstructured planar meshes. We adopt this OUM-based solver for surface meshes and present a triangulation-invariant method for the solver. Our basic idea is to explore proximity among the vertices on a surface while locally following the characteristic direction at each vertex. We also propose two speed functions based on classical curvature tensors and show that the resulting anisotropic geodesic maps reflect surface geometry well through several experiments, including isocontour generation, offset curve computation, medial axis extraction, and ridge/valley curve extraction. Our approach facilitates surface analysis and processing by defining speed functions in an application-dependent manner.

  11. A triangulation-invariant method for anisotropic geodesic map computation on surface meshes.

    PubMed

    Yoo, Sang Wook; Seong, Joon-Kyung; Sung, Min-Hyuk; Shin, Sung Yo; Cohen, Elaine

    2012-10-01

    This paper addresses the problem of computing the geodesic distance map from a given set of source vertices to all other vertices on a surface mesh using an anisotropic distance metric. Formulating this problem as an equivalent control theoretic problem with Hamilton-Jacobi-Bellman partial differential equations, we present a framework for computing an anisotropic geodesic map using a curvature-based speed function. An ordered upwind method (OUM)-based solver for these equations is available for unstructured planar meshes. We adopt this OUM-based solver for surface meshes and present a triangulation-invariant method for the solver. Our basic idea is to explore proximity among the vertices on a surface while locally following the characteristic direction at each vertex. We also propose two speed functions based on classical curvature tensors and show that the resulting anisotropic geodesic maps reflect surface geometry well through several experiments, including isocontour generation, offset curve computation, medial axis extraction, and ridge/valley curve extraction. Our approach facilitates surface analysis and processing by defining speed functions in an application-dependent manner. PMID:22291150

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

    DOEpatents

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

    1994-01-01

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

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

    USGS Publications Warehouse

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

    2012-01-01

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

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

    USGS Publications Warehouse

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

    2012-01-01

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

  15. Evaluating near-surface soil moisture using Heat Capacity Mapping Mission data

    NASA Technical Reports Server (NTRS)

    Heilman, J. L.; Moore, D. G.

    1982-01-01

    Four dates of Heat Capacity Mapping Mission (HCMM) data were analyzed in order to evaluate HCMM thermal data use in estimating near-surface soil moisture in a complex agricultural landscape. Because of large spatial and temporal ground cover variations, HCMM radiometric temperatures alone did not correlate with soil water content. The radiometric temperatures consisted of radiance contributions from different canopies and their respective soil backgrounds. However, when surface soil temperatures were empirically estimated from HCMM temperatures and percent cover of each pixel, a highly significant correlation was obtained between the estimated soil temperatures and near-surface soil water content.

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

    USGS Publications Warehouse

    Chapelle, Frank; Drummond, Dave; Curley, Tracey

    1981-01-01

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

  17. Surface charge microscopy: novel technique for mapping charge-mosaic surfaces in electrolyte solutions.

    PubMed

    Yin, Xihui; Drelich, Jaroslaw

    2008-08-01

    The effective surface potential, called the zeta potential, is commonly determined from electrophoretic mobility measurements for particles moving in a solution in response to an electric field applied between two electrodes. The situation can be reversed, with the solution being forced to flow through a plug of packed particles, and the streaming potential of the particles can be calculated. A significant limitation of these electrokinetic measurements is that only an average value of the zeta potential/streaming potential is measured--regardless of whether the surface charge distribution is homogeneous or otherwise. However, in real-world situations, nearly all solids (and liquids) of technological significance exhibit surface heterogeneities. To detect heterogeneities in surface charge, analytical tools which provide accurate and spatially resolved information about the material surface potential--particularly at microscopic and submicroscopic resolutions--are needed. In this study, atomic force microscopy (AFM) was used to measure the surface interaction forces between a silicon nitride AFM cantilever and a multiphase volcanic rock. The experiments were conducted in electrolyte solutions with different ionic strengths and pH values. The colloidal force measurements were carried out stepwise across the boundary between adjacent phases. At each location, the force-distance curves were recorded. Surface charge densities were then calculated by fitting the experimental data with a DLVO theoretical model. Significant differences between the surface charge densities of the two phases and gradual transitions in the surface charge density at the interface were observed. It is demonstrated that this novel technique can be applied to examine one- and two-dimensional distributions of the surface potential. PMID:18620435

  18. Surface charge microscopy: novel technique for mapping charge-mosaic surfaces in electrolyte solutions.

    PubMed

    Yin, Xihui; Drelich, Jaroslaw

    2008-08-01

    The effective surface potential, called the zeta potential, is commonly determined from electrophoretic mobility measurements for particles moving in a solution in response to an electric field applied between two electrodes. The situation can be reversed, with the solution being forced to flow through a plug of packed particles, and the streaming potential of the particles can be calculated. A significant limitation of these electrokinetic measurements is that only an average value of the zeta potential/streaming potential is measured--regardless of whether the surface charge distribution is homogeneous or otherwise. However, in real-world situations, nearly all solids (and liquids) of technological significance exhibit surface heterogeneities. To detect heterogeneities in surface charge, analytical tools which provide accurate and spatially resolved information about the material surface potential--particularly at microscopic and submicroscopic resolutions--are needed. In this study, atomic force microscopy (AFM) was used to measure the surface interaction forces between a silicon nitride AFM cantilever and a multiphase volcanic rock. The experiments were conducted in electrolyte solutions with different ionic strengths and pH values. The colloidal force measurements were carried out stepwise across the boundary between adjacent phases. At each location, the force-distance curves were recorded. Surface charge densities were then calculated by fitting the experimental data with a DLVO theoretical model. Significant differences between the surface charge densities of the two phases and gradual transitions in the surface charge density at the interface were observed. It is demonstrated that this novel technique can be applied to examine one- and two-dimensional distributions of the surface potential.

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

    NASA Astrophysics Data System (ADS)

    Vandersteen, Katrijn; Gedeon, Matej

    2013-04-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-06-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

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

  2. Reconstruction of an optical surface from a given source-target map.

    PubMed

    Doskolovich, Leonid L; Andreev, Evgeniy S; Kharitonov, Sergey I; Kazansky, Nikolay L

    2016-08-01

    We propose a new method for the reconstruction of a reflecting (refracting) surface from a given source-target map defining the relationships between the directions of incident and reflected (refracted) rays. In the proposed method, the optical surface is represented as an envelope of a set of paraboloids (reflecting surface) or ellipsoids (refracting surface). This representation allows the problem of design of an optical surface to be reduced to the reconstruction of a function from its total differential. We illustrate the proposed approach by designing mirrors generating a far-field uniform illuminance in a square target. The calculation results show that the proposed method enables the generation of high-quality illuminance distributions even when the integrability condition is not satisfied. PMID:27505648

  3. Surface identification from multiband LADAR reflectance with varied incidence angle via database mapping.

    PubMed

    Guiang, Chona; Jin, Xuemin; Levine, Robert Y

    2015-02-10

    Incident angle dependencies of LADAR reflection depend on bulk material reflectivity and surface texture properties that can be exploited for surface identification. In this paper, surface identification via multiband LADAR reflected radiance is assessed using the nonconventional exploitation factors data system database. A statistics-based dimension reduction algorithm, stochastic neighborhood embedding (t-SNE), is used to separate the data clouds resulting from the monostatic LADAR reflected radiance and corresponding band ratios. The application of t-SNE to multiband reflected radiance effectively separates the data clouds, making surface identification via multiband LADAR reflectance possible in the presence of unknown incident angle dependencies and uncertainties. It is demonstrated that, for both the multiband monostatic reflected radiance and band ratios, the application of t-SNE mapping yields a significant improvement in surface identification from measurements with unknown or varied incident angles.

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

    PubMed Central

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

    2013-01-01

    Studying and controlling reactions at surfaces is of great fundamental and applied interest in, among others, biology, electronics and catalysis. Because reaction kinetics is different at surfaces compared with solution, frequently, solution-characterization techniques cannot be used. Here we report solution gradients, prepared by electrochemical means, for controlling and monitoring reactivity at surfaces in space and time. As a proof of principle, electrochemically derived gradients of a reaction parameter (pH) and of a catalyst (Cu(I)) have been employed to make surface gradients on the micron scale and to study the kinetics of the (surface-confined) imine hydrolysis and the copper(I)-catalysed azide-alkyne 1,3-dipolar cycloaddition, respectively. For both systems, the kinetic data were spatially visualized in a two-dimensional reactivity map. In the case of the copper(I)-catalysed azide-alkyne 1,3-dipolar cycloaddition, the reaction order (2) was deduced from it. PMID:23575671

  5. Toddlers default to canonical surface-to-meaning mapping when learning verbs.

    PubMed

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

    2014-01-01

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

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

    PubMed Central

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

    2013-01-01

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

  7. Mineral Physicochemistry based Geoscience Products for Mapping the Earth's Surface and Subsurface

    NASA Astrophysics Data System (ADS)

    Laukamp, C.; Cudahy, T.; Caccetta, M.; Haest, M.; Rodger, A.; Western Australian Centre of Excellence3D Mineral Mapping

    2011-12-01

    Mineral maps derived from remotes sensing data can be used to address geological questions about mineral systems important for exploration and mining. This paper focuses on the application of geoscience-tuned multi- and hyperspectral sensors (e.g. ASTER, HyMap) and the methods to routinely create meaningful higher level geoscience products from these data sets. The vision is a 3D mineral map of the earth's surface and subsurface. Understanding the physicochemistry of rock forming minerals and the related diagnostic absorption features in the visible, near, mid and far infrared is a key for mineral mapping. For this, reflectance spectra obtained with lab based visible and infrared spectroscopic (VIRS) instruments (e.g. Bruker Hemisphere Vertex 70) are compared to various remote and proximal sensing techniques. Calibration of the various sensor types is a major challenge with any such comparisons. The spectral resolution of the respective instruments and the band positions are two of the main factors governing the ability to identify mineral groups or mineral species and compositions of those. The routine processing method employed by the Western Australian Centre of Excellence for 3D Mineral Mapping (http://c3dmm.csiro.au) is a multiple feature extraction method (MFEM). This method targets mineral specific absorption features rather than relying on spectral libraries or the need to find pure endmembers. The principle behind MFEM allows us to easily compare hyperspectral surface and subsurface data, laying the foundation for a seamless and accurate 3-dimensional mineral map. The advantage of VIRS techniques for geoscientific applications is the ability to deliver quantitative mineral information over multiple scales. For example, C3DMM is working towards a suite of ASTER-derived maps covering the Australian continent, scheduled for publication in 2012. A suite of higher level geoscience products of Western Australia (e.g. AlOH group abundance and composition) are now

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

    PubMed

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

    2016-07-13

    Surface trap states in copper indium gallium selenide semiconductor nanocrystals (NCs), which serve as undesirable channels for nonradiative carrier recombination, remain a great challenge impeding the development of solar and optoelectronics devices based on these NCs. In order to design efficient passivation techniques to minimize these trap states, a precise knowledge about the charge carrier dynamics on the NCs surface is essential. However, selective mapping of surface traps requires capabilities beyond the reach of conventional laser spectroscopy and static electron microscopy; it can only be accessed by using a one-of-a-kind, second-generation four-dimensional scanning ultrafast electron microscope (4D S-UEM) with subpicosecond temporal and nanometer spatial resolutions. Here, we precisely map the collective surface charge carrier dynamics of copper indium gallium selenide NCs as a function of the surface trap states before and after surface passivation in real space and time using S-UEM. The time-resolved snapshots clearly demonstrate that the density of the trap states is significantly reduced after zinc sulfide (ZnS) shelling. Furthermore, the removal of trap states and elongation of carrier lifetime are confirmed by the increased photocurrent of the self-biased photodetector fabricated using the shelled NCs. PMID:27228321

  9. Accuracy and precision of stream reach water surface slopes estimated in the field and from maps

    USGS Publications Warehouse

    Isaak, D.J.; Hubert, W.A.; Krueger, K.L.

    1999-01-01

    The accuracy and precision of five tools used to measure stream water surface slope (WSS) were evaluated. Water surface slopes estimated in the field with a clinometer or from topographic maps used in conjunction with a map wheel or geographic information system (GIS) were significantly higher than WSS estimated in the field with a surveying level (biases of 34, 41, and 53%, respectively). Accuracy of WSS estimates obtained with an Abney level did not differ from surveying level estimates, but conclusions regarding the accuracy of Abney levels and clinometers were weakened by intratool variability. The surveying level estimated WSS most precisely (coefficient of variation [CV] = 0.26%), followed by the GIS (CV = 1.87%), map wheel (CV = 6.18%), Abney level (CV = 13.68%), and clinometer (CV = 21.57%). Estimates of WSS measured in the field with an Abney level and estimated for the same reaches with a GIS used in conjunction with l:24,000-scale topographic maps were significantly correlated (r = 0.86), but there was a tendency for the GIS to overestimate WSS. Detailed accounts of the methods used to measure WSS and recommendations regarding the measurement of WSS are provided.

  10. The effect of psychoemotional load on ventricular repolarization reflected in integral body surface potential maps.

    PubMed

    Kellerová, E; Regecová, V; Katina, S; Titomir, L I; Aidu, E A I; Trunov, V G; Szathmáry, V

    2006-01-01

    The aim of the present study was to investigate the reflection of psychoemotional stress in the body surface potential distribution as documented by isointegral maps of cardiac activation and recovery. In 72 young men (18.3+/- 7.3 y.) with no cardiovascular history body surface potential maps (BSPMs) at rest and during the test of mental arithmetic were recorded. The digitalized data for each point of the QRS, STT and QRST integral maps, for each subject in both situations, were processed and evaluated by methods of univariate as well as spatial mathematical and statistical modeling. The results showed during MA a significant decrease of repolarization integral values over the sternum and right precordium, which contributed to analogically localized decrements also in the QRST BSM. The decrease occurred in more than 2/3 of lead points. The most pronounced changes were observed in the right precordial area, where potentials decreased in more than in 70 % of subjects. In conclusion, the discriminative power of the difference STT and QRST integral maps was strong enough to distinguish the mental arithmetic induced changes in the superficial cardiac electric field. These adrenergic transient alterations in ventricular recovery may be of importance in subjects at risk for ventricular arrhythmias.

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

    SciTech Connect

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

    2014-01-03

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

  12. Estimating and Mapping Urban Impervious Surfaces: Reflection on Spectral, Spatial, and Temporal Resolutions

    NASA Astrophysics Data System (ADS)

    Weng, Q.

    2007-12-01

    Impervious surface is a key indicator of urban environmental quality and urbanization degree. Therefore, estimation and mapping of impervious surfaces in urban areas has attracted more and more attention recently by using remote sensing digital images. In this paper, satellite images with various spectral, spatial, and temporal resolutions are employed to examine the effects of these remote sensing data characteristics on mapping accuracy of urban impervious surfaces. The study area was the city proper of Indianapolis (Marion County), Indiana, United States. Linear spectral mixture analysis was applied to generate high albedo, low albedo, vegetation, and soil fraction images (endmembers) from the satellite images, and impervious surfaces were then estimated by adding high albedo and low albedo fraction images. A comparison of EO-1 ALI (multispectral) and Hyperion (hyperspectral) images indicates that the Hyperion image was more effective in discerning low albedo surface materials, especially the spectral bands in the mid-infrared region. Linear spectral mixing modeling was found more useful for medium spatial resolution images, such as Landsat TM/ETM+ and ASTER images, due to the existence of a large amount of mixed pixels in the urban areas. The model, however, may not be suitable for high spatial resolution images, such as IKONOS images, because of less influence from the mixing pixel. The shadow problem in the high spatial resolution images, caused by tall buildings and large tree crowns, is a challenge in impervious surface extraction. Alternative image processing algorithms such as decision tree classifier may be more appropriate to achieve high mapping accuracy. For mid-latitude cities, seasonal vegetation phenology has a significant effect on the spectral response of terrestrial features, and therefore, image analysis must take into account of this environmental characteristic. Three ASTER images, acquired on April 5, 2004, June 16, 2001, and October 3, 2000

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

    USGS Publications Warehouse

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

    2005-01-01

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

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

    PubMed Central

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

    2015-01-01

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

  15. Bacterial cell surface display for epitope mapping of hepatitis C virus core antigen.

    PubMed

    Kang, Su-Min; Rhee, Jin-Kyu; Kim, Eui-Joong; Han, Kwang-Hyub; Oh, Jong-Won

    2003-09-26

    Cell surface expression of protein has been widely used to display enzymes and antigens. Here we show that Pseudomonas syringae ice nucleation protein with a deletion of internal repeating domain (INC) can be used in Escherichia coli to display peptide in a conformationally active form on the outside of the folded protein by fusing to the C-terminus of INC. Diagnostic potential of this technology was demonstrated by effective mapping of antigenic epitopes derived from hepatitis C virus (HCV) core protein. Amino acids 1-38 and 26-53 of HCV core protein were found to react more sensitively in a native conformation with the HCV patient sera than commercial diagnostic antigen, c22p (amino acids 10-53) by display-ELISA. These results demonstrate that the bacterial cell surface display using INC is useful for peptide presentation and thus epitope mapping of antigen. PMID:14553932

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

    NASA Technical Reports Server (NTRS)

    Rowland, Scott K.

    1992-01-01

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

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

    PubMed

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

    2015-12-01

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

  18. Note: Electron energy spectroscopy mapping of surface with scanning tunneling microscope.

    PubMed

    Li, Meng; Xu, Chunkai; Zhang, Panke; Li, Zhean; Chen, Xiangjun

    2016-08-01

    We report a novel scanning probe electron energy spectrometer (SPEES) which combines a double toroidal analyzer with a scanning tunneling microscope to achieve both topography imaging and electron energy spectroscopy mapping of surface in situ. The spatial resolution of spectroscopy mapping is determined to be better than 0.7 ± 0.2 μm at a tip sample distance of 7 μm. Meanwhile, the size of the field emission electron beam spot on the surface is also measured, and is about 3.6 ± 0.8 μm in diameter. This unambiguously demonstrates that the spatial resolution of SPEES technique can be much better than the size of the incident electron beam. PMID:27587179

  19. Note: Electron energy spectroscopy mapping of surface with scanning tunneling microscope.

    PubMed

    Li, Meng; Xu, Chunkai; Zhang, Panke; Li, Zhean; Chen, Xiangjun

    2016-08-01

    We report a novel scanning probe electron energy spectrometer (SPEES) which combines a double toroidal analyzer with a scanning tunneling microscope to achieve both topography imaging and electron energy spectroscopy mapping of surface in situ. The spatial resolution of spectroscopy mapping is determined to be better than 0.7 ± 0.2 μm at a tip sample distance of 7 μm. Meanwhile, the size of the field emission electron beam spot on the surface is also measured, and is about 3.6 ± 0.8 μm in diameter. This unambiguously demonstrates that the spatial resolution of SPEES technique can be much better than the size of the incident electron beam.

  20. Mapping the total phosphorus concentration of biosolid amended surface soils using LANDSAT TM data.

    PubMed

    Sridhar, B B Maruthi; Vincent, Robert K; Witter, Jason D; Spongberg, Alison L

    2009-04-01

    Conventional methods for soil sampling and analysis for soil variability in chemical characteristics are too time-consuming and expensive for multi-seasonal monitoring over large-scale areas. Hence, the objectives of this study are: 1) to determine changes in chemical concentrations of soils that are amended with treated sewage sludge; and 2) to determine if LANDSAT TM data can be used to map surface chemical characteristics of such amended soils. For this study, we selected two fields in NW Ohio, designated as F34 and F11, that had been applied with 34 and 11 ton acre(-1) of biosolids, respectively. Soil samples from a total of 70 sampling locations across the two fields were collected one day prior to LANDSAT 5 overpass and were analyzed for several elemental concentrations. The accumulation of Ba, Cd, Cu, S and P were found to be significantly higher in the surface soils of field F34, compared to field F11. Regression equations were established to search for algorithms that could map these five elemental concentrations in the surface soils using six, dark-object-subtracted (DOS) LANDSAT TM bands and the 15 non-reciprocal spectral ratios derived from these six bands for the May 20, 2005, LANDSAT 5 TM image. Phosphorus (P) had the highest R(2) adjusted value (67.9%) among all five elements considered, and the resulting algorithm employed only spectral ratios. This model was successfully tested for robustness by applying it to another LANDSAT TM image obtained on June 5, 2005. Our results enabled us to conclude that LANDSAT TM imagery of bare-soil fields can be used to quantify and map the spatial variation of total phosphorous concentration in surface soils. This research has significant implications for identification and mapping of areas with high P, which is important for implementing and monitoring the best phosphorous management practices across the region.

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

    NASA Technical Reports Server (NTRS)

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

    1989-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

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

    USGS Publications Warehouse

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

    2011-01-01

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

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

    USGS Publications Warehouse

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

    1998-01-01

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

  5. Salts on Europa's surface detected by Galileo's near infrared mapping spectrometer. The NIMS Team.

    PubMed

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

    1998-05-22

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

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

    NASA Astrophysics Data System (ADS)

    Liang, S.; Wang, D.

    2015-12-01

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

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

    NASA Astrophysics Data System (ADS)

    Beresko, Christian; Kohns, Peter; Ankerhold, Georg

    2014-09-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1992-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Lavelle, Joseph; Schuet, Stefan

    2006-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  11. Mapping Land and Water Surface Topography with instantaneous Structure from Motion

    NASA Astrophysics Data System (ADS)

    Dietrich, J.; Fonstad, M. A.

    2012-12-01

    Structure from Motion (SfM) has given researchers an invaluable tool for low-cost, high-resolution 3D mapping of the environment. These SfM 3D surface models are commonly constructed from many digital photographs collected with one digital camera (either handheld or attached to aerial platform). This method works for stationary or very slow moving objects. However, objects in motion are impossible to capture with one-camera SfM. With multiple simultaneously triggered cameras, it becomes possible to capture multiple photographs at the same time which allows for the construction 3D surface models of moving objects and surfaces, an instantaneous SfM (ISfM) surface model. In river science, ISfM provides a low-cost solution for measuring a number of river variables that researchers normally estimate or are unable to collect over large areas. With ISfM and sufficient coverage of the banks and RTK-GPS control it is possible to create a digital surface model of land and water surface elevations across an entire channel and water surface slopes at any point within the surface model. By setting the cameras to collect time-lapse photography of a scene it is possible to create multiple surfaces that can be compared using traditional digital surface model differencing. These water surface models could be combined the high-resolution bathymetry to create fully 3D cross sections that could be useful in hydrologic modeling. Multiple temporal image sets could also be used in 2D or 3D particle image velocimetry to create 3D surface velocity maps of a channel. Other applications in earth science include anything where researchers could benefit from temporal surface modeling like mass movements, lava flows, dam removal monitoring. The camera system that was used for this research consisted of ten pocket digital cameras (Canon A3300) equipped with wireless triggers. The triggers were constructed with an Arduino-style microcontroller and off-the-shelf handheld radios with a maximum

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

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2009-12-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2012-01-01

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

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

    USGS Publications Warehouse

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

    1982-01-01

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

  16. Radiation climate map for analyzing risks to astronauts on the mars surface from galactic cosmic rays

    NASA Astrophysics Data System (ADS)

    Saganti, Premkumar B.; Cucinotta, Francis A.; Wilson, John W.; Simonsen, Lisa C.; Zeitlin, Cary

    2004-01-01

    The potential risks for late effects including cancer, cataracts, and neurological disorders due to exposures to the galactic cosmic rays (GCR) is a large concern for the human exploration of Mars. Physical models are needed to project the radiation exposures to be received by astronauts in transit to Mars and on the Mars surface, including the understanding of the modification of the GCR by the Martian atmosphere and identifying shielding optimization approaches. The Mars Global Surveyor (MGS) mission has been collecting Martian surface topographical data with the Mars Orbiter Laser Altimeter (MOLA). Here we present calculations of radiation climate maps of the surface of Mars using the MOLA data, the radiation transport model HZETRN (high charge and high energy transport), and the quantum multiple scattering fragmentation model, QMSFRG. Organ doses and the average number of particle hits per cell nucleus from GCR components (protons, heavy ions, and neutrons) are evaluated as a function of the altitude on the Martian surface. Approaches to improve the accuracy of the radiation climate map, presented here using data from the 2001 Mars Odyssey mission, are discussed.

  17. Radiation Climate Map for Analyzing Risks to Astronauts on the Mars Surface from Galactic Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Saganti, Premkumar B.; Cucinotta, Francis A.; Wilson, John W.; Simonsen, Lisa C.; Zeitlin, Cary

    The potential risks for late effects including cancer, cataracts, and neurological disorders due to exposures to the galactic cosmic rays (GCR) is a large concern for the human exploration of Mars. Physical models are needed to project the radiation exposures to be received by astronauts in transit to Mars and on the Mars surface, including the understanding of the modification of the GCR by the Martian atmosphere and identifying shielding optimization approaches. The Mars Global Surveyor (MGS) mission has been collecting Martian surface topographical data with the Mars Orbiter Laser Altimeter (MOLA). Here we present calculations of radiation climate maps of the surface of Mars using the MOLA data, the radiation transport model HZETRN (high charge and high energy transport), and the quantum multiple scattering fragmentation model, QMSFRG. Organ doses and the average number of particle hits per cell nucleus from GCR components (protons, heavy ions, and neutrons) are evaluated as a function of the altitude on the Martian surface. Approaches to improve the accuracy of the radiation climate map, presented here using data from the 2001 Mars Odyssey mission, are discussed.

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

    PubMed Central

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

    2015-01-01

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

  19. Mapping plasmonic near-field profiles and interferences by surface-enhanced Raman scattering

    PubMed Central

    Du, Luping; Lei, Dang Yuan; Yuan, Guanghui; Fang, Hui; Zhang, Xi; Wang, Qian; Tang, Dingyuan; Min, Changjun; Maier, Stefan A.; Yuan, Xiaocong

    2013-01-01

    Mapping near-field profiles and dynamics of surface plasmon polaritons is crucial for understanding their fundamental optical properties and designing miniaturized photonic devices. This requires a spatial resolution on the sub-wavelength scale because the effective polariton wavelength is shorter than free-space excitation wavelengths. Here by combining total internal reflection excitation with surface-enhanced Raman scattering imaging, we mapped at the sub-wavelength scale the spatial distribution of the dominant perpendicular component of surface plasmon fields in a metal nanoparticle-film system through spectrally selective and polarization-resolved excitation of the vertical gap mode. The lateral field-extension at the junction, which is determined by the gap-mode volume, is small enough to distinguish a spot size ~0.355λ0 generated by a focused radially polarized beam with high reproducibility. The same excitation and imaging schemes are also used to trace near-field nano-focusing and interferences of surface plasmon polaritons created by a variety of plasmon lenses. PMID:24165970

  20. Mapping impervious surface area in the Brazilian Amazon using Landsat Imagery

    PubMed Central

    Li, Guiying; Lu, Dengsheng; Moran, Emilio; Hetrick, Scott

    2013-01-01

    Impervious surface area (ISA) is an important parameter related to environmental change and socioeconomic conditions, and has been given increasing attention in the past two decades. However, mapping ISA using remote sensing data is still a challenge due to the variety and complexity of materials comprising ISA and the limitations of remote sensing data spectral and spatial resolution. This paper examines ISA mapping with Landsat Thematic Mapper (TM) images in urban and urban–rural landscapes in the Brazilian Amazon. A fractional-based method and a per-pixel based method were used to map ISA distribution, and their results were evaluated with QuickBird images based on the 2010 Brazilian census at the sector scale of analysis for examining the mapping performance. This research showed that the fraction-based method improved the ISA estimation, especially in urban–rural frontiers and in a landscape with a small urban extent. Large errors were mainly located at the sites having ISA proportions of 0.2–0.4 in a census sector. Calibration with high spatial resolution data is valuable for improving Landsat-based ISA estimates. PMID:24151451

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

    SciTech Connect

    Mauer, Georg F.; Kawa, Chris

    2008-01-15

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-09-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

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

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

    SciTech Connect

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

    2014-06-15

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

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

    NASA Technical Reports Server (NTRS)

    Price, J. C.

    1979-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1977-01-01

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

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

    USGS Publications Warehouse

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

    1981-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-10-01

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

  9. Risk assessment of ventricular arrhythmia using new parameters based on high resolution body surface potential mapping

    PubMed Central

    Fereniec, Malgorzata; Stix, Gunter; Kania, Michal; Mroczka, Tomasz; Janusek, Dariusz; Maniewski, Roman

    2011-01-01

    Summary Background The effective screening of myocardial infarction (MI) patients threatened by ventricular tachycardia (VT) is an important issue in clinical practice, especially in the process of implantable cardioverter-defibrillator (ICD) therapy recommendation. This study proposes new parameters describing depolarization and repolarization inhomogeneity in high resolution body surface potential maps (HR BSPM) to identify MI patients threatened by VT. Material/Methods High resolution ECGs were recorded from 64 surface leads. Time-averaged HR BSPMs were used. Several parameters for arrhythmia risk assessment were calculated in 2 groups of MI patients: those with and without documented VT. Additionally, a control group of healthy subjects was studied. To assess the risk of VT, the following parameters were proposed: correlation coefficient between STT and QRST integral maps (STT_QRST_CORR), departure index of absolute value of STT integral map (STT_DI), and departure index of absolute value of T-wave shape index (TSI_DI). These new parameters were compared to known parameters: QRS width, QT interval, QT dispersion, Tpeak-Tend interval, total cosines between QRS complex and T wave, and non-dipolar content of QRST integral maps. Results STT_DI, TSI_DI, STT_QRST_CORR, QRS width, and QT interval parameters were statistically significant (p≤0.05) in arrhythmia risk assessment. The highest sensitivity was found for the STT_DI parameter (0.77) and the highest specificity for TSI_DI (0.79). Conclusions Arrhythmia risk is demonstrated by both abnormal spatial distribution of the repolarization phase and changed relationship between depolarization and repolarization phases, as well as their prolongation. The proposed new parameters might be applied for risk stratification of cardiac arrhythmia. PMID:21358612

  10. Impervious Surface Mapping of Jungnang-cheon Basin of Korea Using Remote Sensing Images

    NASA Astrophysics Data System (ADS)

    Kim, S.; Heo, J.

    2007-12-01

    Impervious surface is the important index for the estimation of urbanization and environmental change. In addition, impervious surface affects on various hydrological process such as the short-term rainfall runoff modeling, water balance analysis, and groundwater estimation in urban area. Therefore, the estimation of impervious surface is an important factor to analyze urban flood. The main objective of this study is the impervious surface mapping of case study area using remote sensing images. Case study area is Jungnang- cheon basin in South Korea. Remote sensing images for the impervious surface mapping are landsat-7 ETM+ and high resolution satellite image of Jungnang-cheon basin. Moreover, a tasseled cap transformation and NDVI transformation apply to landsat-7 ETM+ for considering various predicted parameters. Impervious surface is estimated by using regression tree algorithm which is a binary recursive partitioning process and a rule-based model for the prediction of continuous variables based on training data. Regression tree algorithm is applied to training data sets which are collected by overlaying between landsat-7 ETM+ and high resolution satellite image with different spatial resolution. Then, the predicted variables such as band 3(red), band 4(nearIR), band 5(midIR), and band 7(nearIR) of landsat-7 ETM+ and TC2(greenness) and TC3(wetness) of a tasseled cap transformed image and NDVI transformed image are selected for the efficient and fast prediction modeling. The independent variable of model is a continuous impervious index represented by percentage. The accuracy of variables combination is compared by the average error(AE), the relative error(RE), and correlation coefficient. As the results, the selected test composes with band 3, 4, 5 and 7 of landsat-7 ETM+, the greenness of a tasseled cap transformed image and NDVI. It shows the highest correlation coefficient(0.92) and the smallest the total average error(9.2). In addition, 10-folds cross

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

    SciTech Connect

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

    2007-10-23

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

  12. Directly mapping the surface charge density of lipid bilayers under physiological conditions

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

    The surface charge density of lipid bilayers governs the cellular uptake of charged particles and guides cell-cell and cell-surface interactions. Direct probing of the potential requires sub nanometer distances as the electrostatic potential is screened by high physiological salt concentrations. This prevented direct measurement of the SCD under physiological conditions. In this study we investigate supported bilayers of lipid mixtures that form domains of distinct surface charges, submerged in 150mM NaCl. We use a scanning ion-conductance microscope (SICM) setup to measure the ionic current through a nanopipette as the pipette is scanned several nanometers above the sample. The charged headgroups of the lipids attract counter ions leading to a charge dependent enhancement of the ion concentration near the surface. This creates a measurable change of conductivity in the vicinity of the surface. As the dependency of the current on the SCD and pipette potential is non-trivial we characterized it using numerical solutions to Poisson and Nernst-Planck equations. Based on the simulation results we propose an imaging method. We confirm feasibility of the proposed method by experimentally mapping the local surface charge density of phase separated lipid bilayers.

  13. Application of DLVO energy map to evaluate interactions between spherical colloids and rough surfaces.

    PubMed

    Shen, Chongyang; Wang, Feng; Li, Baoguo; Jin, Yan; Wang, Lian-Ping; Huang, Yuanfang

    2012-10-16

    This study theoretically evaluated interactions between spherical colloids and rough surfaces in three-dimensional space using Derjaguin-Landau-Verwey- Overbeek (DLVO) energy/force map and curve. The rough surfaces were modeled as a flat surface covered by hemispherical protrusions. A modified Derjaguin approach was employed to calculate the interaction energies and forces. Results show that more irreversible attachments in primary minima occur at higher ionic strengths, which theoretically explains the observed hysteresis of colloid attachment and detachment during transients in solution chemistry. Secondary minimum depths can be increased significantly in concave regions (e.g., areas aside of asperities or between asperities) due to sidewall interactions. Through comparing the tangential attractive forces from asperities and the hydrodynamic drag forces in three-dimensional space, we showed that attachment in secondary minima can be located on open collector surfaces of a porous medium. This result challenges the usual belief that the attachment in secondary minima only occurs in stagnation point regions of the porous medium and is absent in shear flow systems such as parallel plate flow chamber and impinging jet apparatus. Despite the argument about the role of secondary minima in colloid attachment remained, our study theoretically justified the existence of attachment in secondary minima in the presence of surface roughness. Further, our study implied that the presence of surface roughness is more favorable for attachment in secondary minima than in primary minima under unfavorable chemical conditions.

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

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2009-05-01

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

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

    NASA Astrophysics Data System (ADS)

    Li, Peng; Jones, Peter R. M.

    1997-03-01

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

  17. Nanoscale imaging and hydrophobicity mapping of the antimicrobial effect of copper on bacterial surfaces.

    PubMed

    Wang, Congzhou; Ehrhardt, Christopher J; Yadavalli, Vamsi K

    2016-09-01

    Copper has a long historical role in the arena of materials with antimicrobial properties. Various forms of copper ranging from surfaces to impregnation in textiles and particles, have attracted considerable interest owing to their versatility, potency, chemical stability, and low cost. However, the effects and mechanisms of their antimicrobial action is still unclear. In this study, the effect of copper particles on Escherichia coli was studied at the nanoscale using atomic force microscopy (AFM). Time-lapse AFM images at the single cell level show the morphological changes on live E. coli during antimicrobial treatment, in which for the first time, this process was followed in situ on the same cell over time. AFM-based hydrophobicity mapping further showed that incubating cells with Cu decreased the surface hydrophobicity with an increase of incubation time. Specifically, we are able to visualize both morphology and physico-chemical nature of the bacterial cell surface change in response to copper treatment, leading to the membrane damage and cytoplasm leakage. Overall, the time-lapse AFM imaging combined with hydrophobicity mapping approach presented here provides spatio-temporal insight into the antimicrobial mechanisms of copper at the single cell level, and can be applied to design of better metallic antimicrobial materials as well as investigate different microorganisms. PMID:27258941

  18. A LiDAR based analysis of hydraulic hazard mapping

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

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

  19. Visualizing surface states of topological insulators using spectroscopic mapping with the scanning tunneling microscope

    NASA Astrophysics Data System (ADS)

    Roushan, Pedram

    2011-03-01

    In topological insulators, the spin texture of the surface states makes them distinct from conventional two-dimensional electron states, and leads to novel properties for these states. These surface states are expected to be immune to localization and to overcome barriers caused by material imperfections. We have used scanning tunneling microscopy and spectroscopy to study the topological surface states in Bi 0.9 Sb 0.1 , Sb, and Bi 2 Te 3 . By mapping the interference of the surface states scattering off random alloying disorder in Bi 0.9 Sb 0.1 , we have demonstrated that despite strong atomic scale disorder, backscattering between states of opposite momentum and opposite spin is absent, resulting from the spin texture. Furthermore, we have measured the transmission and reflection of topological surface states of Sb through atomic terraces. In contrast to Schottky surface states of noble metals, these surface states penetrate such barriers with high probability. To examine the possibility of disorder induced localization, we investigated the surface states of Bi 2 Te 3 in the presence of local defects. In the presence of magnetic dopants, we have observed an interference pattern throughout a broad range of energies, even in the region of linear dispersion near the Dirac point. We discuss the results of a statistical analysis of these patterns which can help to learn about the tendency toward localization for these surface states and how this trend is affected as the energy is tuned to the Dirac point. *Work was done in collaboration with J. Seo, H. Beidenkopf, L. Gorman, Y. S. Hor, C. Parker, D. Hsieh, and A. Richardella, M. Z. Hasan, R. Cava, and A. Yazdani. Supported by NSF-DMR, and MRSEC through PCCM. Infrastructure at Princeton Nanoscale Microscopy Laboratory are also supported by grants from DOE, and the W.M. Keck foundation.

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  1. Mapping soil surface macropores using infrared thermography: an exploratory laboratory study.

    PubMed

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

    2014-01-01

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

  2. Calibrating transmissivities from piezometric heads with the gradual deformation method: An application to the Culebra Dolomite unit at the Waste Isolation Pilot Plant (WIPP), New Mexico, USA

    NASA Astrophysics Data System (ADS)

    Le Ravalec, Mickaële; Mouche, Emmanuel

    2012-11-01

    SummaryThe gradual deformation method (GDM) is a geostatistical parameterization technique introduced in reservoir engineering for compelling reservoir models to respect production history. It makes it possible to adjust the spatial distribution of the hydraulic properties populating the reservoir model so that the flow responses simulated for the modified model closely replicate the production data collected on the field. The work presented in this paper investigates the potential of the GDM to solve inverse problems in hydrogeology, or subsurface hydrology, and produce heterogeneous transmissivity fields conditional to both transmissivity and piezometric head measurements within a stochastic context. It focuses on the calibration of the Culebra Dolomite unit, which lies approximately 450 m above the repository horizon of the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico, USA. Results show that the proposed version of the GDM, with a local deformation in each sub-domain neighboring a well, is efficient and competitive compared to other geostatistical-based inverse methods such as the pilot point method.

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

    NASA Astrophysics Data System (ADS)

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

    2016-02-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-06-01

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

  5. A new method for automated discontinuity trace mapping on rock mass 3D surface model

    NASA Astrophysics Data System (ADS)

    Li, Xiaojun; Chen, Jianqin; Zhu, Hehua

    2016-04-01

    This paper presents an automated discontinuity trace mapping method on a 3D surface model of rock mass. Feature points of discontinuity traces are first detected using the Normal Tensor Voting Theory, which is robust to noisy point cloud data. Discontinuity traces are then extracted from feature points in four steps: (1) trace feature point grouping, (2) trace segment growth, (3) trace segment connection, and (4) redundant trace segment removal. A sensitivity analysis is conducted to identify optimal values for the parameters used in the proposed method. The optimal triangular mesh element size is between 5 cm and 6 cm; the angle threshold in the trace segment growth step is between 70° and 90°; the angle threshold in the trace segment connection step is between 50° and 70°, and the distance threshold should be at least 15 times the mean triangular mesh element size. The method is applied to the excavation face trace mapping of a drill-and-blast tunnel. The results show that the proposed discontinuity trace mapping method is fast and effective and could be used as a supplement to traditional direct measurement of discontinuity traces.

  6. Towards a More Realistic Depiction of the Earth's Surface on Maps

    NASA Astrophysics Data System (ADS)

    Drachal, Jacek; Dębowska, Anna

    2014-06-01

    In 2000, the shuttle radar topography mission (SRTM) produced the most complete, highest resolution digital elevation model (DEM) of the Earth. These data were used to create global 3″ DEM and to correct 30″ DEM which are both available on the internet. After a careful survey in the Institute of Geodesy and Cartography, Poland, these elevation data were recognized as extremely valuable and worth developing a unique form of visualization. As a result, a new design of a physical map of Europe at scale of 1:10 million was developed. For depicting the shape of the terrain, an original modification of combined shaded relief was employed, to reveal all the nuances of elevation data. True colors of the Earth's surface represented on the map originated from MODIS satellite image. The combination of true colors and terrain features made a realistic map, showing the landscapes as if from a point above the Earth. The image of the terrain is extremely detailed as it is based on the abundance of data defining the elevation of each point of land.

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

    NASA Technical Reports Server (NTRS)

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

    2013-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

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

  9. Mapping the surface characteristics of the Mojave with remote sensing for terrestrial habitat modeling

    NASA Astrophysics Data System (ADS)

    Nowicki, S. A.; Skuse, R. J.

    2012-12-01

    , apparent thermal inertia, and diurnal/seasonal thermal regime. Additionally, the combination of moderate and high-resolution thermal observations are used to map the spatial and temporal variation of significant rain storms that intermittently increase the surface moisture. The resulting thermally-derived layers are in the process of being combined with composition, vegetation and surface reflectance datasets to map the Mojave at the highest VNIR resolution (20m/pixel) and compared to currently-available lower-resolution datasets.

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

    PubMed

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

    2015-03-11

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

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

    PubMed Central

    An, Yan; Zou, Zhihong; Li, Ranran

    2016-01-01

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

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

    PubMed

    An, Yan; Zou, Zhihong; Li, Ranran

    2016-01-08

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-01-01

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

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

    USGS Publications Warehouse

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

    2003-01-01

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

  15. Mapping Mercury's Surface Composition at High Spatial Resolution with the MESSENGER X-Ray Spectrometer

    NASA Astrophysics Data System (ADS)

    Nittler, L. R.; Weider, S. Z.; Starr, R. D.; Vorburger, A.; Solomon, S. C.

    2014-12-01

    Previous global maps of Mg/Si and Al/Si and partial maps of S/Si, Ca/Si, and Fe/Si on Mercury's surface derived from orbital data acquired by the MESSENGER X-Ray Spectrometer (XRS) have been highly variable in resolution because of MESSENGER's eccentric orbit and high northern periapsis. The typical spatial resolution at northern latitudes in earlier maps was 200-500 km, a scale that allowed large geochemical terranes to be defined and chemical measurements to be made of features hundreds of kilometers in extent, but so far there have been very few analyses at smaller scales. MESSENGER is now orbiting at the lowest periapsis altitudes so far in the mission, and XRS measurements can thus be made at substantially improved resolution. For example, measurements with resolutions <100 km constituted 1% of the northern-hemisphere observations that were used to make the previous maps, but they make up 31% of those obtained in May and June of 2014. Preliminary analysis of these higher-resolution XRS data confirms the broad-scale geochemical features that have already been identified, but also reveals smaller-scale chemical heterogeneities. For instance, targeted XRS measurements indicate that the high-reflectance smooth plains deposit, about 125 km in extent, at the center of the Rachmaninoff basin has Mg/Si=0.6, higher than for other smooth plains deposits with similar reflectance characteristics (for which Mg/Si is typically <0.4), but similar to the darker material surrounding the unit. Although the high-resolution maps that we continue to generate have limited coverage, they reveal substantial chemical heterogeneity at the 100-km scale both within the northern volcanic plains and within the large high-Mg region that has been previously identified. In many cases, the chemical heterogeneity we observe is closely associated with spatial variations in spectral reflectance properties. Continued observations at ever lower altitudes will allow chemical mapping on Mercury at

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

    NASA Astrophysics Data System (ADS)

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

    2016-10-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  18. Mapping Electrochemical Heterogeneity at Iron Oxide Surfaces: A Local Electrochemical Impedance Study.

    PubMed

    Lucas, Marie; Boily, Jean-François

    2015-12-22

    Alternating current scanning electrochemical microscopy (AC-SECM) was used for the first time to map key electrochemical attributes of oriented hematite (α-Fe2O3) single crystal surfaces at the micron-scale. Localized electrochemical impedance spectra (LEIS) of the (001) and (012) faces provided insight into the spatial variations of local double layer capacitance (C(dl)) and charge transfer resistance (R(ad)). These parameters were extracted by LEIS measurements in the 0.4-8000 Hz range to probe the impedance response generated by the redistribution of water molecules and charge carriers (ions) under an applied AC. These were attributed to local variations in the local conductivity of the sample surfaces. Comparison with global EIS measurements on the same samples uncovered highly comparable frequency-resolved processes, that were broken down into contributions from the bulk hematite, the interface as well as the microelectrode/tip assembly. This work paves the way for new studies aimed at mapping electrochemical processes at the mesoscale on this environmentally and technologically important material.

  19. A quantitative analysis of signal reproduction from cylinder recordings measured via noncontact full surface mapping.

    PubMed

    Nascè, Antony; Hill, Martyn; McBride, John W; Boltryk, Peter J

    2008-10-01

    Sound reproduction via a noncontact surface mapping technique has great potential for sound archives, aiming to digitize content from early sound recordings such as wax cylinders, which may otherwise be "unplayable" with a stylus. If the noncontact techniques are to be considered a viable solution for sound archivists, a method for quantifying the quality of the reproduced signal needs to be developed. In this study, a specially produced test cylinder recording, encoded with sinusoids, provides the basis for the first quantitative analysis of signal reproduction from the noncontact full surface mapping method. The sampling and resolution of the measurement system are considered with respect to the requirements for digital archiving of cylinder recordings. Two different methods of audio signal estimation from a discrete groove cross section are described and rated in terms of signal-to-noise ratio and total harmonic distortion. Noncontact and stylus methods of sound reproduction are then compared using the same test cylinder. It is shown that noncontact methods appear to have distinct advantages over stylus reproduction, in terms of reduced harmonic distortion and lower frequency modulation. PMID:19062844

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

    USGS Publications Warehouse

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

    2005-01-01

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

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

    USGS Publications Warehouse

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

    2010-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2004-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-07-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

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

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

    USGS Publications Warehouse

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

    1980-01-01

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

  8. Mapping the impact of climate change on surface recession of carbonate buildings in Europe.

    PubMed

    Bonazza, Alessandra; Messina, Palmira; Sabbioni, Cristina; Grossi, Carlota M; Brimblecombe, Peter

    2009-03-01

    Climate change is currently attracting interest at both research and policy levels. However, it is usually explored in terms of its effect on agriculture, water, industry, energy, transport and health and as yet has been insufficiently addressed as a factor threatening cultural heritage. Among the climate parameters critical to heritage conservation and expected to change in the future, precipitation plays an important role in surface recession of stone. The Lipfert function has been taken under consideration to quantify the annual surface recession of carbonate stone, due to the effects of clean rain, acid rain and dry deposition of pollutants. The present paper provides Europe-wide maps showing quantitative predictions of surface recession on carbonate stones for the 21st century, combining a modified Lipfert function with output from the Hadley global climate model. Chemical dissolution of carbonate stones, via the karst effect, will increase with future CO(2) concentrations, and will come to dominate over sulfur deposition and acid rain effects on monuments and buildings in both urban and rural areas. During the present century the rainfall contribution to surface recession is likely to have a small effect, while the increase in atmospheric CO(2) concentration is shown to be the main factor in increasing weathering via the karst effect.

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

    NASA Astrophysics Data System (ADS)

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

    2010-12-01

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

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

    USGS Publications Warehouse

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

    1995-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2016-01-01

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

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

    USGS Publications Warehouse

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

    2013-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Fu, Lee-Lueng; Morrow, Rosemary

    2016-07-01

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

  14. Quasi-minimal Lorentz surfaces with pointwise 1-type Gauss map in pseudo-Euclidean 4-space

    NASA Astrophysics Data System (ADS)

    Milousheva, Velichka; Turgay, Nurettin Cenk

    2016-08-01

    A Lorentz surface in the four-dimensional pseudo-Euclidean space with neutral metric is called quasi-minimal if its mean curvature vector is lightlike at each point. In the present paper we obtain the complete classification of quasi-minimal Lorentz surfaces with pointwise 1-type Gauss map.

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

    EPA Science Inventory

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

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

    SciTech Connect

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

    1994-05-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  18. SUPERFICIAL – Surface mapping of proteins via structure-based peptide library design

    PubMed Central

    Goede, Andrean; Jaeger, Ines S; Preissner, Robert

    2005-01-01

    Background The determination of protein surfaces and the detection of binding sites are essential to our understanding of protein-protein interactions. Such binding sites can be characterised as linear and non-linear, the non-linear sites being prevailant. Conventional mapping techniques with arrays of synthetic peptides have limitations with regard to the location of discontinuous or non-linear binding sites of proteins. Results We present a structure-based approach to the design of peptide libraries that mimic the whole surface or a particular region of a protein. Neighbouring sequence segments are linked by short spacers to conserve local conformation. To this end, we have developed SUPERFICIAL, a program that uses protein structures as input and generates library proposals consisting of linear and non-linear peptides. This process can be influenced by a graphical user interface at different stages, from the surface computation up to the definition of spatial regions. Conclusion Based on 3D structures, SUPERFICIAL may help to negotiate some of the existing limitations, since binding sites consisting of several linear pieces can now be detected. PMID:16153304

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

    USGS Publications Warehouse

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

    1982-01-01

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

  20. Mapping Antigenic Motifs in the Trypomastigote Small Surface Antigen from Trypanosoma cruzi

    PubMed Central

    Balouz, Virginia; Cámara, María de los Milagros; Cánepa, Gaspar E.; Carmona, Santiago J.; Volcovich, Romina; Gonzalez, Nicolás; Altcheh, Jaime; Agüero, Fernán

    2015-01-01

    The trypomastigote small surface antigen (TSSA) is a mucin-like molecule from Trypanosoma cruzi, the etiological agent of Chagas disease, which displays amino acid polymorphisms in parasite isolates. TSSA expression is restricted to the surface of infective cell-derived trypomastigotes, where it functions as an adhesin and engages surface receptors on the host cell as a prerequisite for parasite internalization. Previous results have established TSSA-CL, the isoform encoded by the CL Brener clone, as an appealing candidate for use in serology-based diagnostics for Chagas disease. Here, we used a combination of peptide- and recombinant protein-based tools to map the antigenic structure of TSSA-CL at maximal resolution. Our results indicate the presence of different partially overlapping B-cell epitopes clustering in the central portion of TSSA-CL, which contains most of the polymorphisms found in parasite isolates. Based on these results, we assessed the serodiagnostic performance of a 21-amino-acid-long peptide that spans TSSA-CL major antigenic determinants, which was similar to the performance of the previously validated glutathione S-transferase (GST)-TSSA-CL fusion molecule. Furthermore, the tools developed for the antigenic characterization of the TSSA antigen were also used to explore other potential diagnostic applications of the anti-TSSA humoral response in Chagasic patients. Overall, our present results provide additional insights into the antigenic structure of TSSA-CL and support this molecule as an excellent target for molecular intervention in Chagas disease. PMID:25589551

  1. Three-Dimensional Mapping of Gyral Shape and Cortical Surface Asymmetries in Schizophrenia: Gender Effects

    PubMed Central

    Narr, Katherine L.; Thompson, Paul M.; Sharma, Tonmoy; Moussai, Jacob; Zoumalan, Chris; Rayman, Janice; Toga, Arthur W.

    2008-01-01

    Objective People with schizophrenia exhibit abnormalities in brain structure, often in the left hemisphere. Disturbed structural lateralization is controversial, however, and effects appear mediated by gender. The authors mapped differences between schizophrenic and normal subjects in gyral asymmetries, complexity, and variability across the entire cortex. Method Asymmetry and shape profiles for 25 schizophrenic patients (15 men) and 28 demographically similar normal subjects (15 men) were obtained for 38 gyral regions, including the sylvian fissure and temporal and postcentral gyri, by using magnetic resonance data and a novel surface-based mesh-modeling approach. Cortical complexity was examined for sex and diagnosis effects in lobar regions. Intragroup variability was quantified and visualized to assess regional group abnormalities at the cortical surface. Results The patients showed greater variability in frontal areas than the comparison subjects. They also had significant deviations in gyral complexity asymmetry in the superior frontal cortex. In temporoparietal regions, significant gyral asymmetries were present in both groups. Sex differences were apparent in superior temporal gyral measures, and cortical complexity in inferior frontal regions was significantly greater in men. Conclusions Cortical variability and complexity show regional abnormalities in the frontal cortex potentially specific to schizophrenia. The results indicate highly significant temporoparietal gyral asymmetries in both diagnostic groups, contrary to reports of less lateralization in schizophrenia. Substantially larger study groups are necessary to isolate smaller deviations in surface asymmetries, if present in schizophrenia, suggesting their diagnostic value is minimal. PMID:11156807

  2. ECG body surface mapping in patients with gestational diabetes mellitus and optimal metabolic compensation.

    PubMed

    Žákovičová, E; Kittnar, O; Slavíček, J; Medová, E; Šváb, P; Charvát, J

    2014-01-01

    Women with gestational diabetes mellitus (GDM) are at increased risk for cardiovascular diseases (CVD) events compared with women without GDM. The aim of the present study was to evaluate 200 parameters of the heart electric field in 35 women with GDM under optimal glycemic compensation compared to 32 healthy pregnant women. All examinations were performed in the 36th week of gestation. The parameters in ECG body surface mapping (BSM) were registered by the diagnostic system Cardiag 112.2. The absolute values of maximum and minimum in depolarization and repolarization isopotential, isointegral and isoarea maps were not significantly different between the groups. These findings correspond to the result of heart rate variability examination. However BSM revealed the significant prolongation of QRS complex (p=0.05), shortening of ventricular myocardial activation time (ICHVAT) (p=0.01), prolongation of mean QT duration (p=0.01) and increase of QT interval dispersion (p=0.01) in women with GDM. Duration of QRS and ICHVAT significantly correlated with interventricular septum and posterior wall thickness in GDM group, QTd interval correlated significantly with HbA1C level. We conclude that despite of optimal metabolic control several significant abnormalities detected by ECG BSM are still present in patients with GDM. PMID:25669679

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

    NASA Astrophysics Data System (ADS)

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

    2015-08-01

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

  4. Contactless surface conductivity mapping of graphene oxide thin films deposited on glass with scanning electrochemical microscopy.

    PubMed

    Azevedo, Joel; Bourdillon, Céline; Derycke, Vincent; Campidelli, Stéphane; Lefrou, Christine; Cornut, Renaud

    2013-02-01

    The present article introduces a rapid, very sensitive, contactless method to measure the local surface conductivity with Scanning Electrochemical Microscopy (SECM) and obtain conductivity maps of heterogeneous substrates. It is demonstrated through the study of Graphene Oxide (GO) thin films deposited on glass. The adopted substrate preparation method leads to conductivity disparities randomly distributed over approximately 100 μm large zones. Data interpretation is based on an equation system with the dimensionless conductivity as the only unknown parameter. A detailed prospection provides a consistent theoretical framework for the reliable quantification of the conductivity of GO with SECM. Finally, an analytical approximation of the conductivity as a function of the feedback current is proposed, making any further interpretation procedure straightforward, as it does not require iterative numerical simulations any more. The present work thus provides not only valuable information on the kinetics of GO reduction in mild conditions but also a general and simplified interpretation framework that can be extended to the quantitative conductivity mapping of other types of substrates. PMID:23259661

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

    SciTech Connect

    Not Available

    1988-03-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  7. Modified multiple endmember spectral mixture analysis for mapping impervious surfaces in urban environments

    NASA Astrophysics Data System (ADS)

    Tan, Kun; Jin, Xiao; Du, Qian; Du, Peijun

    2014-01-01

    A modified multiple endmember spectral mixture analysis (MMESMA) approach is proposed for high-spatial-resolution hyperspectral imagery in the application of impervious surface mapping. Different from the original MESMA that usually selects one endmember spectral signature for each land-cover class, the proposed MMESMA allows the selection of multiple endmember signatures for each land-cover class. It is expected that the MMESMA can better accommodate within-class variations and yield better mapping results. Various unmixing models are compared, such as the linear mixing model, linear spectral mixture analysis using the original linear mixture model, original MESMA, and support vector machine using a nonlinear mixture model. Airborne 1-m resolution HySpex and ROSIS data are used in the experiments. For HySpex data, validation based on 25-cm synchronism aerial photography shows that MMESMA performs the best, with the root-mean-squared error (RMSE) of the estimated abundance fractions being 13.20% and the correlation coefficient (R2) being 0.9656. For ROSIS data, validation based on simulation shows that MMESMA performs the best, with the RMSE of the estimated abundance fraction being 4.51% and R2 being 0.9878. These demonstrate that the proposed MMESMA can generate more reliable abundance fractions for high-spatial-resolution hyperspectral imagery, which tends to include strong within-class spectral variations.

  8. Mapping of surface-immobilized DNA with force-based atomic force microscopy.

    PubMed

    Lee, Yoonhee; Kwon, Sung Hong; Kim, Youngkyu; Lee, Jong-Bong; Park, Joon Won

    2013-04-16

    Single-stranded 50-mer, 100-mer, and 150-mer DNAs were immobilized on a surface, and force-based atomic force microscopy (AFM) was employed to examine their behavior. A complementary 20-mer probe DNA on an AFM tip was used for the measurements. High-resolution maps were generated, and relevant parameters, including the force, stretching distance, unbinding probability, cluster size, and degree of distortion, were analyzed. Due to thermal drift, the cluster shape became increasingly distorted as the scan speed was decreased and as the map area was reduced. The cluster radius increased with the number of base (N), and the radius was proportional to N(0.6) (r = 0.977) and N(0.53) (r = 0.991). Due to the effect of the pulling angle, the apparent values of the stretching distance and the unbinding force decreased as the AFM probe was moved away from the center position; these values can be described as a function of sin θ.

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

    USGS Publications Warehouse

    Troutman, Sandra M.; Stanley, Richard G.

    2003-01-01

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

  10. New Display-type Analyzer for Three-dimensional Fermi Surface Mapping and Atomic Orbital Analysis

    SciTech Connect

    Takahashi, Nobuaki; Matsuda, Hiroyuki; Shigenai, Shin; Hirama, Yoshiteru; Matsui, Fumihiko; Hamada, Yoji; Nakanishi, Koji; Namba, Hidetoshi; Kitamura, Toshiro; Soejima, Hiroyoshi; Daimon, Hiroshi

    2007-01-19

    We have developed and installed a new Display-type ANAlyzer (DIANA) at Ritsumeikan SR center BL-7. We measured the angle-integrated energy distribution curve of poly-crystal gold and the photoelectron intensity angular distribution (PIAD) of HOPG to estimate the total energy resolution and to check the condition of the analyzer. The total energy resolution ({delta}E/E) is up to 0.78%, which is much higher than the old type. The PIAD of HOPG we obtained was the ring pattern as expected. Therefore, a detailed three-dimensional Fermi surface mapping and an analysis of the atomic orbitals constituting the electron energy bands are possible by combining them with a linearly polarized synchrotron radiation.

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

    USGS Publications Warehouse

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

    1989-01-01

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

  12. Orbit determination requirements for TOPEX. [NASA ocean surface TOPography mapping EXperiment

    NASA Technical Reports Server (NTRS)

    Tapley, B. D.; Schutz, B. E.; Ries, J.; Rosborough, G.; Born, G. H.

    1981-01-01

    The error sensitivity of orbit calculations in support of the NASA Ocean Surface Topography Mapping Experiment (TOPEX), which require an accuracy on the order of 5 cm, is investigated. The contributions of errors in the gravitational, atmospheric drag and solar radiation pressure models to the computed orbit are analyzed for the cases of an ideal data distribution and realistic laser ranging data coverage. It is found that the major contributor to radial orbital error is the error in the geopotential model, accounting for orbital errors of 30 to 70 cm, with the effects of solar radiation pressure, drag modeling, tracking station coordinate errors making lesser contributions. It is concluded that TOPEX accuracy goals cannot be met using ground-based laser ranging data without improving the geopotential model.

  13. New Display-type Analyzer for Three-dimensional Fermi Surface Mapping and Atomic Orbital Analysis

    NASA Astrophysics Data System (ADS)

    Takahashi, Nobuaki; Matsui, Fumihiko; Matsuda, Hiroyuki; Shigenai, Shin; Hirama, Yoshiteru; Hamada, Yoji; Nakanishi, Koji; Namba, Hidetoshi; Kitamura, Toshiro; Soejima, Hiroyoshi; Daimon, Hiroshi

    2007-01-01

    We have developed and installed a new Display-type ANAlyzer (DIANA) at Ritsumeikan SR center BL-7. We measured the angle-integrated energy distribution curve of poly-crystal gold and the photoelectron intensity angular distribution (PIAD) of HOPG to estimate the total energy resolution and to check the condition of the analyzer. The total energy resolution (ΔE/E) is up to 0.78%, which is much higher than the old type. The PIAD of HOPG we obtained was the ring pattern as expected. Therefore, a detailed three-dimensional Fermi surface mapping and an analysis of the atomic orbitals constituting the electron energy bands are possible by combining them with a linearly polarized synchrotron radiation.

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

    NASA Technical Reports Server (NTRS)

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

    1973-01-01

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

  15. Adiabatic isometric mapping algorithm for embedding 2-surfaces in Euclidean 3-space

    NASA Astrophysics Data System (ADS)

    Ray, Shannon; Miller, Warner A.; Alsing, Paul M.; Yau, Shing-Tung

    2015-12-01

    Alexandrov proved that any simplicial complex homeomorphic to a sphere with strictly non-negative Gaussian curvature at each vertex can be isometrically embedded uniquely in {{{R}}}3 as a convex polyhedron. Due to the nonconstructive nature of his proof, there have yet to be any algorithms, that we know of, that realizes the Alexandrov embedding in polynomial time. Following his proof, we developed the adiabatic isometric mapping (AIM) algorithm. AIM uses a guided adiabatic pull-back procedure on a given polyhedral metric to produce an embedding that approximates the unique Alexandrov polyhedron. Tests of AIM applied to two different polyhedral metrics suggests that its run time is sub cubic with respect to the number of vertices. Although Alexandrov’s theorem specifically addresses the embedding of convex polyhedral metrics, we tested AIM on a broader class of polyhedral metrics that included regions of negative Gaussian curvature. One test was on a surface just outside the ergosphere of a Kerr black hole.

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

    NASA Astrophysics Data System (ADS)

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

    2008-09-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2010-05-01

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

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

    SciTech Connect

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

    1988-05-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1996-01-01

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

  20. Photothermal and photoacoustic methods for mapping surface absorbance: Adaptation for screening chemical and biomolecular libraries

    NASA Astrophysics Data System (ADS)

    Koebel, Matthias M.

    Photoacoustic and photothermal methods are useful tools for the analysis of solid state samples and thin films. Both techniques may be used to study surface absorber distributions on surfaces. In the photoacoustic experiment, light absorption at a solid/air interface launches a pressure wave which propagates through the air. The acoustic wave is detected by deflection of a probe laser beam. For non-parallel orientation of the probe beam with respect to the sample surface, acoustic waves launched from individual absorber features travel different distances before they intersect with the probe beam. This allows temporal encoding of the spatial distribution of surface absorbers. An experimental demonstration of this novel photoacoustic of detection scheme is presented. In the photothermal experiment, detection is based on production of a temperature change at the sample surface following light absorption. Thermal diffusion generates temperature gradients in the solid sample and the adjacent fluid layer. The resulting refractive index gradient in the adjacent fluid medium is measured by deflection of a probe laser beam. Using the transverse photothermal deflection spectroscopy (t-PDS) method, two dimensional absorber distribution maps of a flat sample surface can be recorded. A number of colored thin polymer film are used to characterize the sensitivity in air and a value of 7.5 · 10-6 W is found. Gold nanoparticles are excellent optical absorber labels for biological and biochemical binding assays. The synthesis and characterization of gold nanoparticles of different sizes and surface chemical functionalities is presented. A novel readout method for protein microarrays based on photothermal detection of nanoparticle labeled proteins is described. Protein microarrays are developed with functionalized gold nanoparticles and analyzed using t-PDS. The observed coloration intensity performance depends on the intrinsic nature of the target protein. Neutravidin produces the

  1. Mapping Precipitation Patterns from the Stable Isotopic Composition of Surface Waters: Olympic Peninsula, Washington State

    NASA Astrophysics Data System (ADS)

    Anders, A. M.; Brandon, M. T.

    2008-12-01

    Available data indicate that large and persistent precipitation gradients are tied to topography at scales down to a few kilometers, but precipitation patterns in the majority of mountain ranges are poorly constrained at scales less than tens of kilometers. A lack of knowledge of precipitation patterns hampers efforts to understand the processes of orographic precipitation and identify the relationships between geomorphic evolution and climate. A new method for mapping precipitation using the stable isotopic composition of surface waters is tested in the Olympic Mountains of Washington State. Measured δD and δ18O of 97 samples of surface water are linearly related and nearly inseparable from the global meteoric water line. A linear orographic precipitation model extended to include in effects of isotopic fractionation via Rayleigh distillation predicts precipitation patterns and isotopic composition of surface water. Seven parameters relating to the climate and isotopic composition of source water are used. A constrained random search identifies the best-fitting parameter set. Confidence intervals for parameter values are defined and precipitation patterns are determined. Average errors for the best-fitting model are 4.8 permil in δD. The difference between the best fitting model and other models within the 95% confidence interval was less than 20%. An independent high-resolution precipitation climatology documents precipitation gradients similar in shape and magnitude to the model derived from surface water isotopic composition. This technique could be extended to other mountain ranges, providing an economical and fast assessment of precipitation patterns requiring minimal field work.

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

    NASA Astrophysics Data System (ADS)

    Chesley, S.; Farnocchia, D.

    2014-07-01

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

  3. Satellite Based Mapping of Land Surface ET using MODIS and Alternate Surface Meteorological Inputs from AMSR-E, Reanalysis, and Surface Weather Stations

    NASA Astrophysics Data System (ADS)

    Mu, Q.; Jones, L. A.; Kimball, J. S.; Running, S. W.

    2007-12-01

    Regional evapotranspiration (ET), including water loss from plant transpiration and soil evaporation, is essential to understanding interactions between land-atmosphere surface energy and water balances. Vapor pressure deficit (VPD) and surface air temperature are key variables for stomatal conductance and ET estimation. We developed an algorithm to estimate ET using a modified Penman-Monteith approach driven by MODIS derived vegetation data and daily surface meteorological inputs including net incoming solar radiation, air temperature and VPD. The model was applied using alternate daily meteorological inputs, including: 1) site level weather station observations, 2) VPD and air temperature derived from the Advanced Microwave Scanning Radiometer (AMSR-E) on the EOS Aqua satellite, and 3) Global Modeling and Assimilation Office (GMAO) reanalysis based surface temperature, humidity and solar radiation data. Model performance was assessed across a North American boreal-Arctic transect (>50o N) of six eddy covariance flux towers representing boreal grassland, boreal forest and tundra biomes. Model results derived from the three meteorology data sets agree well with observed tower fluxes (r>0.6; P<0.00001; RMSE<30W/m2) and capture spatial patterns and seasonal variability in ET. The MODIS-AMSR-E derived ET results also show comparable accuracy to ET results derived from the reanalysis meteorology, while ET estimation error was generally more a function of algorithm parameterization than differences in meteorology drivers. Our results indicate significant potential for regional mapping and monitoring daily land surface evaporation using synergistic information from satellite optical-IR and microwave remote sensing.

  4. 3D Surface Mapping of Capsule Fill-Tube Assemblies used in Laser-Driven Fusion Targets

    SciTech Connect

    Buice, E S; Alger, E T; Antipa, N A; Bhandarkar, S D; Biesiada, T A; Conder, A D; Dzenitis, E G; Flegel, M S; Hamza, A V; Heinbockel, C L; Horner, J; Johnson, M A; Kegelmeyer, L M; Meyer, J S; Montesanti, R C; Reynolds, J L; Taylor, J S; Wegner, P J

    2011-02-18

    This paper presents the development of a 3D surface mapping system used to measure the surface of a fusion target Capsule Fill-Tube Assembly (CFTA). The CFTA consists of a hollow Ge-doped plastic sphere, called a capsule, ranging in outer diameter between 2.2 mm and 2.6 mm and an attached 150 {micro}m diameter glass-core fill-tube that tapers down to a 10{micro} diameter at the capsule. The mapping system is an enabling technology to facilitate a quality assurance program and to archive 3D surface information of each capsule used in fusion ignition experiments that are currently being performed at the National Ignition Facility (NIF). The 3D Surface Mapping System is designed to locate and quantify surface features with a height of 50 nm and 300 nm in width or larger. Additionally, the system will be calibrated such that the 3D measured surface can be related to the capsule surface angular coordinate system to within 0.25 degree (1{sigma}), which corresponds to approximately 5 {micro}m linear error on the capsule surface.

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

    PubMed

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

    2015-01-01

    Piezoelectric actuators and sensors are widely used for flow control valves, including diesel injectors, ultrasound generation, optical positioning, printing, pumps, and locks. Degradation and failure of material and electrical properties at high temperature typically limits these applications to operating temperatures below 200°C, based on the ubiquitous Pb(Zr,Ti)O3 ceramic. There are, however, many applications in sectors such as automotive, aerospace, energy and process control, and oil and gas, where the ability to operate at higher temperatures would open up new markets for piezoelectric actuation. Presented here is a review of recent progress and initial results toward a European effort to develop measurement techniques to characterize high-temperature materials. Full-field, multi-wavelength absolute length interferometry has, for the first time, been used to map the electric-field-induced piezoelectric strain across the surface of a PZT ceramic. The recorded variation as a function of temperature has been evaluated against a newly developed commercial single-beam system. Conventional interferometry allows measurement of the converse piezoelectric effect with high precision and resolution, but is often limited to a single point, average measurement and to limited sample environments because of optical aberrations in varying atmospheres. Here, the full-field technique allows the entire surface to be analyzed for strain and, in a bespoke sample chamber, for elevated temperatures. PMID:25585393

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

    NASA Astrophysics Data System (ADS)

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

    2015-09-01

    We describe the design and testing of a point contact tunneling spectroscopy device that can measure material surface superconducting properties (i.e., the superconducting gap Δ and the critical temperature TC) and density of states over large surface areas with size up to mm2. The tip lateral (X,Y) motion, mounted on a (X,Y,Z) piezo-stage, was calibrated on a patterned substrate consisting of Nb lines sputtered on a gold film using both normal (Al) and superconducting (PbSn) tips at 1.5 K. The tip vertical (Z) motion control enables some adjustment of the tip-sample junction resistance that can be measured over 7 orders of magnitudes from a quasi-ohmic regime (few hundred Ω) to the tunnel regime (from tens of kΩ up to few GΩ). The low noise electronic and LabVIEW program interface are also presented. The point contact regime and the large-scale motion capabilities are of particular interest for mapping and testing the superconducting properties of macroscopic scale superconductor-based devices.

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

    PubMed

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

    2015-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-09-01

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

  10. Superresolution fluorescence mapping of single-nanoparticle catalysts reveals spatiotemporal variations in surface reactivity

    PubMed Central

    Zhang, Yuwei; Lucas, J. Matthew; Song, Ping; Beberwyck, Brandon; Fu, Qiang; Xu, Weilin; Alivisatos, A. Paul

    2015-01-01

    For the practical application of nanocatalysts, it is desirable to understand the spatiotemporal fluctuations of nanocatalytic activity at the single-nanoparticle level. Here we use time-lapsed superresolution mapping of single-molecule catalysis events on individual nanoparticles to observe time-varying changes in the spatial distribution of catalysis events on Sb-doped TiO2 nanorods and Au triangle nanoplates. Compared with the active sites on well-defined surface facets, the defects of the nanoparticle catalysts possess higher intrinsic reactivity but lower stability. Corners and ends are more reactive but also less stable than flat surfaces. Averaged over time, the most stable sites dominate the total apparent activity of single nanocatalysts. However, the active sites with higher intrinsic activity but lower stability show activity at earlier time points before deactivating. Unexpectedly, some active sites are found to recover their activity (“self-healing”) after deactivation, which is probably due to desorption of the adsorbate. Our superresolution measurement of different types of active catalytic sites, over both space and time, leads to a more comprehensive understanding of reactivity patterns and may enable the design of new and more productive heterogeneous catalysts. PMID:26150516

  11. Quantitative Evaluation of Peptide-Material Interactions by a Force Mapping Method: Guidelines for Surface Modification.

    PubMed

    Mochizuki, Masahito; Oguchi, Masahiro; Kim, Seong-Oh; Jackman, Joshua A; Ogawa, Tetsu; Lkhamsuren, Ganchimeg; Cho, Nam-Joon; Hayashi, Tomohiro

    2015-07-28

    Peptide coatings on material surfaces have demonstrated wide application across materials science and biotechnology, facilitating the development of nanobio interfaces through surface modification. A guiding motivation in the field is to engineer peptides with a high and selective binding affinity to target materials. Herein, we introduce a quantitative force mapping method in order to evaluate the binding affinity of peptides to various hydrophilic oxide materials by atomic force microscopy (AFM). Statistical analysis of adhesion forces and probabilities obtained on substrates with a materials contrast enabled us to simultaneously compare the peptide binding affinity to different materials. On the basis of the experimental results and corresponding theoretical analysis, we discuss the role of various interfacial forces in modulating the strength of peptide attachment to hydrophilic oxide solid supports as well as to gold. The results emphasize the precision and robustness of our approach to evaluating the adhesion strength of peptides to solid supports, thereby offering guidelines to improve the design and fabrication of peptide-coated materials.

  12. Toward mapping surface deformation in three dimensions using InSAR

    USGS Publications Warehouse

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

    2004-01-01

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

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

    PubMed

    Deng, Zhong-Shan; Liu, Jing

    2004-09-01

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

  14. Laser electro-optic system for rapid three-dimensional /3-D/ topographic mapping of surfaces

    NASA Technical Reports Server (NTRS)

    Altschuler, M. D.; Altschuler, B. R.; Taboada, J.

    1981-01-01

    It is pointed out that the generic utility of a robot in a factory/assembly environment could be substantially enhanced by providing a vision capability to the robot. A standard videocamera for robot vision provides a two-dimensional image which contains insufficient information for a detailed three-dimensional reconstruction of an object. Approaches which supply the additional information needed for the three-dimensional mapping of objects with complex surface shapes are briefly considered and a description is presented of a laser-based system which can provide three-dimensional vision to a robot. The system consists of a laser beam array generator, an optical image recorder, and software for controlling the required operations. The projection of a laser beam array onto a surface produces a dot pattern image which is viewed from one or more suitable perspectives. Attention is given to the mathematical method employed, the space coding technique, the approaches used for obtaining the transformation parameters, the optics for laser beam array generation, the hardware for beam array coding, and aspects of image acquisition.

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

    SciTech Connect

    Morgan, M.A.

    1989-07-01

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

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

    SciTech Connect

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

    2015-09-15

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

  17. Mapping surface energy flux partitioning at large scales with optical and microwave remote sensing data from Washita '92

    NASA Astrophysics Data System (ADS)

    Kustas, William P.; Zhan, Xiwu; Jackson, Thomas J.

    1999-01-01

    A model evaluating the energy balance of the soil/substrate and vegetation (i.e., two-source) was applied to remotely sensed near-surface soil moisture maps generated from passive microwave data collected during the Washita '92 experiment. Model parameters were derived from a soil texture and a land-use/land cover database along with a normalized difference vegetation index map created from a SPOT satellite image. The Bowen ratio (BO, ratio of sensible to latent heat flux) was used for investigating the temporal and spatial variability in model output. Comparisons between predicted and observed heat fluxes were made with values summed over the daytime period. Daily maps of midday BO indicated areas with low vegetation cover or bare soil and senescent vegetation were drying out significantly (i.e., dramatic increases in BO), while other areas with higher vegetation cover showed smaller increases in BO in response to a drying soil surface. This result agrees with the profile soil moisture and surface flux observations indicating adequate moisture was available to the vegetation for meeting atmospheric demand. The predicted daytime fluxes agreed to within 1 mm of the observations with ≈25% difference between modeled and observed daytime evapotranspiration. Differences between modeled and measured surface temperatures averaged ≈2 K. The discrepancies between model output and observations are similar to the uncertainty in these measurements, indicating that the model provided reliable daytime energy flux maps for the Washita '92 study area using remotely sensed near-surface soil moisture.

  18. Restoration of geological surface-UNFOLD method-a validation of complex structural mapping interpretation in the Andean Thrust Belt

    SciTech Connect

    Guillier, B. ); Oller, J.; Mendez, E.; Leconte, J.C.; Letouzey, J.; Specht, M.; Gratier, J.P.

    1993-02-01

    One of the most important problems in petroleum structural geology is dependable interpretation of structural maps obtained by seismic and sub-surface data. One method for validating the geometry of geological structures is the balancing cross-section technique which allows verification of cross-section geometry by a return to its initial horizontal state. However, this can not be used for of 3D halokinesis, shale tectonics, structures formed by polyphased noncoaxial tectonic events, or strike-slip and wrench faulting. An alternative approach is to test the restoration of folded and faulted surfaces to verify 3D structures by balancing geological surfaces represented by a structural map. This method tests the geometry of studied horizon and faults and is based upon the fact that, initially, actual folded/faulted structures were continuous at deposition. The balancing surface program, UNFOLD, restores the actual geological surface to its initial state. Misfits along faults implied poor structural map drawings or strong internal deformation of the geological level. By trial and error method, we returned to the initial data interpretation modifications. This method has been applied to 2D and 3D seismic structural interpretation in different structural styles, environments, rift zones, salt basins, wrench faulting, thrust belt,etc. Some applications to oil field structures in the Andean Thrust Belt have been done to check and validate the complex structural mapping interpretation.

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

    USGS Publications Warehouse

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

    1982-01-01

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

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

    SciTech Connect

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

    1996-10-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  2. Single-pass Airborne InSAR for Wide-swath, High-Resolution Cryospheric Surface Topography Mapping

    NASA Astrophysics Data System (ADS)

    Moller, D.; Hensley, S.; Wu, X.; Muellerschoen, R.

    2014-12-01

    In May 2009 a mm-wave single-pass interferometric synthetic aperture radar (InSAR) for the first time demonstrated ice surface topography swath-mapping in Greenland. This was achieved with the airborne Glacier and Ice Surface Topography Interferometer (GLISTIN-A). Ka-band (35.6GHz) was chosen for high-precision topographic mapping from a compact sensor with minimal surface penetration. In recent years, the system was comprehensively upgraded for improved performance, stability and calibration. In April 2013, after completing the upgrades, GLISTIN-A flew a brief campaign to Alaska. The primary purpose was to demonstrate the InSAR's ability to generate high-precision, high resolution maps of ice surface topography with swaths in excess of 10km. Comparison of GLISTIN-A's elevations over glacial ice with lidar verified the precision requirements and established elevation accuracies to within 2 m without tie points. Feature tracking of crevasses on Columbia Glacier using data acquired with a 3-day separation exhibit an impressive velocity mapping capability. Furthermore, GLISTIN-A flew over the Beaufort sea to determine if we could not only map sea ice, but also measure freeboard. Initial analysis has established we can measure sea-ice freeboard using height differences from the top of the sea-ice and the sea surface in open leads. In the future, a campaign with lidar is desired for a quantitative validation. Another proof-of-concept collection mapped snow-basins for hydrology. Snow depth measurements using summer and winter collections in the Sierras were compared with lidar measurements. Unsurprisingly when present, trees complicate the interpretation, but additional filtering and processing is in work. For each application, knowledge of the interferometric penetration is important for scientific interpretation. We present analytical predictions and experimental data to upper bound the elevation bias of the InSAR measurements over snow and snow-covered ice.

  3. Analysis of aeromagnetic anomalies; mapping of Curie isothermal surface at Long Valley, California

    SciTech Connect

    Miyazaki, Y.

    1985-01-01

    The objective of this study was to gain an understanding of the nature and extent of the Long Valley geothermal system at depth. Airborne magnetic data was used to calculate the Curie isotherm depth for mapping the underground temperature distribution using a spectral analysis and Marquardt non-linear least squares method. Other geophysical and topographic data, such as gravity, Landsat and Digital Terrain Model combined with aeromagnetic data were also used to understand the tectonic structure at depth. These data were geometrically corrected and registered to the basic UTM map, and displayed with a technique of computer color-graphics. In spectral analysis, the Maximum Entropy power spectrum was used to estimate the Curie isotherm depth rather than FET spectrum because this can produce high resolution with accurate frequency and power estimates even for short data samples. The result of magnetic analysis showed that the east-half of Long Valley caldera is cool with curie depth of about 8 km, while the west-half is very hot with Curie depth of about 4.5 km. These estimates are reasonable depths from the surface heat flow data, and are also consistent with the temperature distribution obtained by deep hole data. This fact suggests that the Curie depth analysis is a very encouraging technique and tool for the geothermal exploration. The superimposed image data of geophysical and topographic data suggested that Hilton Creek fault extends northward all the way to Bridgeport Valley. The preliminary result showed that east of the Hilton Creek fault it is cool while to the west it is hot. This may be explained by the flow of cool ground-water through the deep fracture zones of the Hilton Creek fault.

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

    NASA Astrophysics Data System (ADS)

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

    2005-12-01

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

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

    USGS Publications Warehouse

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

    2007-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Kruse, Fred A.; Dwyer, John L.

    1993-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1976-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Hudson, A.; Hansen, M.

    2015-12-01

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

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

    SciTech Connect

    Leckie, D.A.; Vanbeselaere, N.

    1995-11-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-01-01

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

  12. Accelerometer based measurement for the mapping of neck surface vibrations during vocalized speech.

    PubMed

    Nolan, Mark; Madden, Brian; Burke, Edward

    2009-01-01

    This paper presents a detailed study of the vibrations on the surface of the neck during a vocalization of predefined fundamental frequency and intensity. This study was carried out as part of a wider investigation into the use of laryngeal vibrations as a channel of communication. Another potential application of this study is in identifying a suitable location for a hands-free electro-larynx for laryngectomees. An analog accelerometer, with dimensions 5x5x1.6mm and of mass 80mg, was used to perform the measurements. It was connected to a 12-bit analog to digital converter via single strands of insulated wire with a diameter of 100 microm. The resulting low inertia of the measuring device minimised the effect of the measuring device on the phenomenon under investigation. The analog to digital converter simultaneously sampled the accelerometer output and a pre-amplified audio signal from a microphone. This preliminary study was carried out on two able-bodied male subjects. Measurements were taken from forty-five preselected locations on the neck. Each subject made the vowel sound /i/ (long 'e') at three different fundamental frequencies, 150Hz, 200Hz and 250Hz. Once the vocal pitch and intensity matched pre-defined target values, a 200 ms recording was captured by a virtual instrument designed in LabVIEW. A detailed map of skin surface vibration amplitude during vocalization is presented and suitable locations for laryngeal vibration measurement are identified. Further more, detailed analysis of the time varying acceleration function at various measurement positions reveals a rich and complex source of information. Novel visualizations of these signals are presented. PMID:19964631

  13. High-Altitude Laser Altimetry from the Global Hawk UAV for Regional Mapping of Surface Topography

    NASA Astrophysics Data System (ADS)

    Blair, J. B.; Rabine, D.; Wake, S.; Hofton, M. A.; Michell, S.

    2012-12-01

    NASA's Land, Vegetation, and Ice Sensor (LVIS) is a high-altitude, full-waveform, geodetic-imaging laser altimeter system of which a UAV-based version (LVIS-GH) is currently being tested. From 20 km above the surface in the Global Hawk UAV, LVIS-GH images surface topography and roughness (including forest height) across a 4 km wide swath using 15 m diameter footprints. In recent years, the LVIS has been flown at altitudes of up to 14 km over Greenland and Antarctica on flights up to 12 hours in duration, enabling the efficient and precise mapping of large areas from the air. The Global Hawk will extend this capability to up to 32 hours and altitudes approaching 20 km. In order to achieve decimeter level vertical precision and accuracy from high altitude, advanced parameter estimation techniques, based on those implemented in NASA's GEODYN software, are used to estimate the angular, spatial, and temporal biases required to accurately georeference the component lidar data sets. Data from specific in-air maneuvers are utilized in order to isolate the effects of different error sources and to break correlations between biases. Examples of high-altitude data and airborne/spaceborne sensor intercomparison and fusion will be shown. For example, the comparison of data from NASA's ICESat-1 mission with coincident LVIS data collected around 86S (the maximum extent of data collected during ICESat) to quantify inter-campaign biases in Icesat-1 elevation measurements and improve estimates of long -term elevation change rates of ice sheets will be shown. These results illustrate the utility of high-altitude wide swath imaging, particularly from platforms such as the Global-Hawk, for enhancing spacebased data sets.

  14. Multi-spectrum retrieval of Venus IR surface emissivity maps from VIRTIS/VEX nightside measurements at Themis Regio

    NASA Astrophysics Data System (ADS)

    Kappel, David; Arnold, Gabriele; Haus, Rainer

    2016-02-01

    Surface emissivity maps in the infrared can contribute to explore Venus' geology. Nightside radiance spectra at Themis Regio acquired by the IR mapping channel of the Visible and InfraRed Thermal Imaging Spectrometer (VIRTIS-M-IR) aboard Venus EXpress (VEX) are used to derive emissivity data from the three accessible spectral surface windows at 1.02, 1.10, and 1.18 μm. The measured spectra are simulated by applying a full radiative transfer model. Neglecting geologic activity, a multi-spectrum retrieval algorithm is utilized to determine the emissivity maps of the surface target as parameter vectors that are common to many spectrally resolved images that cover this target. Absolute emissivity values are difficult to obtain due to strong interferences from other parameters. The true emissivity mean of the target cannot be retrieved, nor can the emissivity mean of a retrieved map be strictly preset. The retrieved map can exhibit trends with latitude and topography that are probably artificial. Once the trends have been removed in a post-processing step, it can be observed that the magnitude of the resulting spatial emissivity fluctuations around their mean value increases with increasing mean value. A linear transformation is applied that converts the de-trended map to exhibit a defined emissivity mean value called reference emissivity, here 0.5, yielding the 'renormalized emissivity map' with accordingly transformed fluctuations. It is verified that renormalized emissivity maps are largely independent of the emissivity mean before renormalization, of modifications to interfering atmospheric, surface, and instrumental parameters, and of selected details of the retrieval pipeline and data calibration and preprocessing. Extremely large emissivity retrieval errors due to imperfect or unconsidered forward model parameters are effectively avoided. If the absolute emissivity at a given bin of the target were known, the absolute emissivity map of the entire target could be

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

    SciTech Connect

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

    1998-06-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-06-01

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

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

    PubMed

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

    2006-03-28

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

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

    NASA Astrophysics Data System (ADS)

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

    2006-03-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-04-01

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

  20. Arm and wrist surface potential mapping for wearable ECG rhythm recording devices: a pilot clinical study

    NASA Astrophysics Data System (ADS)

    Lynn, W. D.; Escalona, O. J.; McEneaney, D. J.

    2013-06-01

    This study addresses an important question in the development of a ECG device that enables long term monitoring of cardiac rhythm. This device would utilise edge sensor technologies for dry, non-irritant skin contact suitable for distal limb application and would be supported by embedded ECG denoising processes. Contemporary ECG databases including those provided by MIT-BIH and Physionet are focused on interpretation of cardiac disease and rhythm tracking. The data is recorded using chest leads as in standard clinical practise. For the development of a peripherally located heart rhythm monitor, such data would be of limited use. To provide a useful database adequate for the development of the above mentioned cardiac monitoring device a unipolar body surface potential map from the left arm and wrist was gathered in 37 volunteer patients and characterized in this study. For this, the reference electrode was placed at the wrist. Bipolar far-field electrogram leads were derived and analysed. Factors such as skin variability, 50Hz noise interference, electrode contact noise, motion artifacts and electromyographic noise, presented a challenge. The objective was quantify the signal-to-noise ratio (SNR) at the far-field locations. Preliminary results reveal that an electrogram indicative of the QRS complex can be recorded on the distal portion of the left arm when denoised using signal averaging techniques.

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

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

    SciTech Connect

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

    2010-03-15

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

  3. Risk mapping of pesticides: the Dutch atlas of pesticide concentrations in surface waters: www.pesticidesatlas.nl.

    PubMed

    de Snoo, G R; Tamis, W L M; Vijver, M G; Musters, C; van 't Zelfde, M

    2006-01-01

    Many pesticides are being measured in surface water. To promote the use of monitoring data in the process of risk mapping, post-registration, and improvement of water quality, a free available Internet tool has been developed to present all measurements of pesticides in surface water on the level of individual active ingredients in a spatial framework: the Dutch pesticides atlas (www.pesticidesatlas.nl). With this communication tool one can easily get maps concerning where a pesticide is being measured, observed and possibly constitutes a problem over the years. Pesticide concentrations are being compared with environmental standards and maps can been made of each pesticide at a national level. The pesticide maps have been linked with GIS land use data. At present statistical correlations can be made between crop areas and pesticides concentrations in the water. Moreover, predictions can be made where a pesticide might be exceeding environmental standards. Policy makers, chemical industry (product stewardship), NGO's and farmers can use the maps as a tool for communication and improving environmental quality. The atlas is also being used to evaluate the effectiveness of pesticide policy over the years. In this contribution the methodological background of the pesticides atlas is presented.

  4. A Web-based tool for processing and visualizing body surface potential maps.

    PubMed

    Bond, Raymond R; Finlay, Dewar D; Nugent, Chris D; Moore, George

    2010-01-01

    The body surface potential map (BSPM) is potentially more accurate for diagnosing cardiac pathologies when compared to the standard 12-lead electrocardiogram (ECG). However, a contributing factor to the lack of widespread adoption of the BSPM is the shortage of standard methods for its storage and visualization. Based on these observations, a BSPM storage format based on the eXtensible Markup Language has been developed within this study, alongside a Web-based BSPM viewer. This viewer was created using a lossless vector graphics tool (Adobe Flash) to maintain the quality of the ECG waveforms when they are enlarged. The viewer also runs inside the Web browser to facilitate BSPM visualization independent of the clinician's geographical location. This online nature enabled the creation of a comments system that can be used to assist in a collaborative diagnosis. This is useful because BSPM diagnostic criteria are not well established. Moreover, using the viewer's innovative tools (ie, calipers, isopotential maps), the clinician can explore BSPM datasets. Algorithms have also been integrated within the system to extract and display the 12-lead ECG and the vectorcardiogram from the BSPM. This viewer has been available online for 10 months alongside a Weblog, which has been used to record the user's feedback. During this period, 12 experts from both the clinical and visualization domains evaluated the viewer and contributed to its design. It has been the general consensus of all experts that the application is an effective solution for visualizing BSPMs. This viewer has been tested to visualize 2 different BSPMs using a PC (3 GHz CPU, 3 GB RAM, 6 MB broadband). The Lux-192 BSPM and the Kornreich-117 BSPM where both uploaded and visualized within 3.8 seconds (mean time from 10 trials). This BSPM storage format and its associated viewer provide a framework for a BSPM management system. If this system is made widely available, it has the potential to provide BSPM

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

    USGS Publications Warehouse

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

    2001-01-01

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

  6. In vivo microcirculation imaging of the sub surface fingertip using correlation mapping optical coherence tomography (cmOCT)

    NASA Astrophysics Data System (ADS)

    Dsouza, Roshan I.; Zam, Azhar; Subhash, Hrebesh M.; Larin, Kirill V.; Leahy, Martin

    2013-02-01

    We describe a novel application of correlation mapping optical coherence tomography (cmOCT) for sub-surface fingerprint biometric identification. Fingerprint biometrics including automated fingerprint identification systems, are commonly used to recognise the fingerprint, since they constitute simple, effective and valuable physical evidence. Spoofing of biometric fingerprint devices can be easily done because of the limited information obtained from the surface topography. In order to overcome this limitation a potentially more secure source of information is required for biometric identification applications. In this study, we retrieve the microcirculation map of the subsurface fingertip by use of the cmOCT technique. To increase probing depth of the sub surface microcirculation, an optical clearing agent composed of 75% glycerol in aqueous solution was applied topically and kept in contact for 15 min. OCT intensity images were acquired from commercial research grade swept source OCT system (model OCT1300SS, Thorlabs Inc. USA). A 3D OCT scan of the fingertip was acquired over an area of 5x5 mm using 1024x1024 A-scans in approximately 70 s. The resulting volume was then processed using the cmOCT technique with a 7x7 kernel to provide a microcirculation map. We believe these results will demonstrate an enhanced security level over artificial fingertips. To the best of our knowledge, this is the first demonstration of imaging microcirculation map of the subsurface fingertip.

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

    PubMed Central

    2013-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Pokorný, Richard; Tereza Peterková, Marie

    2016-05-01

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

  9. Response surface mapping of neurobehavioral performance: Testing the feasibility of split sleep schedules for space operations

    NASA Astrophysics Data System (ADS)

    Mollicone, Daniel J.; Van Dongen, Hans P. A.; Rogers, Naomi L.; Dinges, David F.

    The demands of sustaining high levels of neurobehavioral performance during space operations necessitate precise scheduling of sleep opportunities in order to best preserve optimal performance. We report here the results of the first split sleep, dose-response experiment involving a range of sleep/wake scenarios with chronically reduced nocturnal sleep, augmented with a diurnal nap. To characterize performance over all combinations of split sleep in the range studied, we used response surface mapping methodology. Waking neurobehavioral performance was studied in N=90 subjects each assigned to one of 18 sleep regimens consisting of a restricted nocturnal anchor sleep period and a diurnal nap. Psychomotor vigilance task performance and subjective assessments of sleepiness were found to be primarily a function of total time in bed per 24 h regardless of how sleep was divided among nocturnal anchor sleep and diurnal nap periods. Digit symbol substitution task performance was also found to be primarily a function of total time in bed per 24 h; however, accounting for nocturnal sleep duration and nap duration separately provided a small but significant enhancement in the variance explained. The results suggest that reductions in total daily sleep result in a near-linear accumulation of impairment regardless of whether sleep is scheduled as a consolidated nocturnal sleep period or split into a nocturnal anchor sleep period and a diurnal nap. Thus, split sleep schedules are feasible and can be used to enhance the flexibility of sleep/work schedules for space operations involving restricted nocturnal sleep due to mission-critical task scheduling. These results are generally applicable to any continuous industrial operation that involves sleep restriction, night operations, and shift work.

  10. Using dose-surface maps to predict radiation-induced rectal bleeding: a neural network approach.

    PubMed

    Buettner, Florian; Gulliford, Sarah L; Webb, Steve; Partridge, Mike

    2009-09-01

    The incidence of late-toxicities after radiotherapy can be modelled based on the dose delivered to the organ under consideration. Most predictive models reduce the dose distribution to a set of dose-volume parameters and do not take the spatial distribution of the dose into account. The aim of this study was to develop a classifier predicting radiation-induced rectal bleeding using all available information on the dose to the rectal wall. The dose was projected on a two-dimensional dose-surface map (DSM) by virtual rectum-unfolding. These DSMs were used as inputs for a classification method based on locally connected neural networks. In contrast to fully connected conventional neural nets, locally connected nets take the topology of the input into account. In order to train the nets, data from 329 patients from the RT01 trial (ISRCTN 47772397) were split into ten roughly equal parts. By using nine of these parts as a training set and the remaining part as an independent test set, a ten-fold cross-validation was performed. Ensemble learning was used and 250 nets were built from randomly selected patients from the training set. Out of these 250 nets, an ensemble of expert nets was chosen. The performances of the full ensemble and of the expert ensemble were quantified by using receiver-operator-characteristic (ROC) curves. In order to quantify the predictive power of the shape, ensembles of fully connected conventional neural nets based on dose-surface histograms (DSHs) were generated and their performances were quantified. The expert ensembles performed better than or equally as well as the full ensembles. The area under the ROC curve for the DSM-based expert ensemble was 0.64. The area under the ROC curve for the DSH-based expert ensemble equalled 0.59. This difference in performance indicates that not only volumetric, but also morphological aspects of the dose distribution are correlated to rectal bleeding after radiotherapy. Thus, the shape of the dose

  11. Sea surface velocities from visible and infrared multispectral atmospheric mapping sensor imagery

    NASA Technical Reports Server (NTRS)

    Pope, P. A.; Emery, W. J.; Radebaugh, M.

    1992-01-01

    High resolution (100 m), sequential Multispectral Atmospheric Mapping Sensor (MAMS) images were used in a study to calculate advective surface velocities using the Maximum Cross Correlation (MCC) technique. Radiance and brightness temperature gradient magnitude images were formed from visible (0.48 microns) and infrared (11.12 microns) image pairs, respectively, of Chandeleur Sound, which is a shallow body of water northeast of the Mississippi delta, at 145546 GMT and 170701 GMT on 30 Mar. 1989. The gradient magnitude images enhanced the surface water feature boundaries, and a lower cutoff on the gradient magnitudes calculated allowed the undesirable sunglare and backscatter gradients in the visible images, and the water vapor absorption gradients in the infrared images, to be reduced in strength. Requiring high (greater than 0.4) maximum cross correlation coefficients and spatial coherence of the vector field aided in the selection of an optimal template size of 10 x 10 pixels (first image) and search limit of 20 pixels (second image) to use in the MCC technique. Use of these optimum input parameters to the MCC algorithm, and high correlation and spatial coherence filtering of the resulting velocity field from the MCC calculation yielded a clustered velocity distribution over the visible and infrared gradient images. The velocity field calculated from the visible gradient image pair agreed well with a subjective analysis of the motion, but the velocity field from the infrared gradient image pair did not. This was attributed to the changing shapes of the gradient features, their nonuniqueness, and large displacements relative to the mean distance between them. These problems implied a lower repeat time for the imagery was needed in order to improve the velocity field derived from gradient imagery. Suggestions are given for optimizing the repeat time of sequential imagery when using the MCC method for motion studies. Applying the MCC method to the infrared

  12. Using dose-surface maps to predict radiation-induced rectal bleeding: a neural network approach

    NASA Astrophysics Data System (ADS)

    Buettner, Florian; Gulliford, Sarah L.; Webb, Steve; Partridge, Mike

    2009-09-01

    The incidence of late-toxicities after radiotherapy can be modelled based on the dose delivered to the organ under consideration. Most predictive models reduce the dose distribution to a set of dose-volume parameters and do not take the spatial distribution of the dose into account. The aim of this study was to develop a classifier predicting radiation-induced rectal bleeding using all available information on the dose to the rectal wall. The dose was projected on a two-dimensional dose-surface map (DSM) by virtual rectum-unfolding. These DSMs were used as inputs for a classification method based on locally connected neural networks. In contrast to fully connected conventional neural nets, locally connected nets take the topology of the input into account. In order to train the nets, data from 329 patients from the RT01 trial (ISRCTN 47772397) were split into ten roughly equal parts. By using nine of these parts as a training set and the remaining part as an independent test set, a ten-fold cross-validation was performed. Ensemble learning was used and 250 nets were built from randomly selected patients from the training set. Out of these 250 nets, an ensemble of expert nets was chosen. The performances of the full ensemble and of the expert ensemble were quantified by using receiver-operator-characteristic (ROC) curves. In order to quantify the predictive power of the shape, ensembles of fully connected conventional neural nets based on dose-surface histograms (DSHs) were generated and their performances were quantified. The expert ensembles performed better than or equally as well as the full ensembles. The area under the ROC curve for the DSM-based expert ensemble was 0.64. The area under the ROC curve for the DSH-based expert ensemble equalled 0.59. This difference in performance indicates that not only volumetric, but also morphological aspects of the dose distribution are correlated to rectal bleeding after radiotherapy. Thus, the shape of the dose

  13. SU-E-J-193: Application of Surface Mapping in Detecting Swallowing for Head-&-Neck Cancer

    SciTech Connect

    Cao, D; Xie, X; Mehta, V; Shepard, D

    2015-06-15

    Purpose: Recent evidence is emerging that long term swallowing function may be improved after radiotherapy for head-&-neck cancer if doses are limited to certain swallowing structures. Immobilization of patients with head-&-neck cancer is typically done with a mask. This mask, however, doesn’t limit patient swallowing. Patient voluntary or involuntary swallowing may introduce significant tumor motion, which can lead to suboptimal delivery. In this study, we have examined the feasibility of using surface mapping technology to detect patient swallowing during treatment and evaluated its magnitude. Methods: The C-RAD Catalyst system was used to detect the patient surface map. A volunteer lying on the couch was used to simulate the patient under treatment. A virtual marker was placed near the throat and was used to monitor the swallowing action. The target motion calculated by the Catalyst system through deformable registration was also collected. Two treatment isocenters, one placed close to the throat and the other placed posterior to the base-of-tongue, were used to check the sensitivity of surface mapping technique. Results: When the patient’s throat is not in the shadow of the patient’s chest, the Catalyst system can clearly identify the swallowing motion. In our tests, the vertical motion of the skin can reach to about 5mm. The calculated target motion can reach up to 1 cm. The magnitude of this calculated target motion is more dramatic when the plan isocenter is closer to the skin surface, which suggests that the Catalyst motion tracking technique is more sensitive to the swallowing motion with a shallower isocenter. Conclusion: Surface mapping can clearly identify patient swallowing during radiation treatment. This information can be used to evaluate the dosimetric impact of the involuntary swallowing. It may also be used to potentially gate head-&-neck radiation treatments. A prospective IRB approved study is currently enrolling patients in our

  14. Real-Time Two-Dimensional Mapping of Relative Local Surface Temperatures with a Thin-Film Sensor Array.

    PubMed

    Li, Gang; Wang, Zhenhai; Mao, Xinyu; Zhang, Yinghuang; Huo, Xiaoye; Liu, Haixiao; Xu, Shengyong

    2016-01-01

    Dynamic mapping of an object's local temperature distribution may offer valuable information for failure analysis, system control and improvement. In this letter we present a computerized measurement system which is equipped with a hybrid, low-noise mechanical-electrical multiplexer for real-time two-dimensional (2D) mapping of surface temperatures. We demonstrate the performance of the system on a device embedded with 32 pieces of built-in Cr-Pt thin-film thermocouples arranged in a 4 × 8 matrix. The system can display a continuous 2D mapping movie of relative temperatures with a time interval around 1 s. This technique may find applications in a variety of practical devices and systems. PMID:27347969

  15. Real-Time Two-Dimensional Mapping of Relative Local Surface Temperatures with a Thin-Film Sensor Array

    PubMed Central

    Li, Gang; Wang, Zhenhai; Mao, Xinyu; Zhang, Yinghuang; Huo, Xiaoye; Liu, Haixiao; Xu, Shengyong

    2016-01-01

    Dynamic mapping of an object’s local temperature distribution may offer valuable information for failure analysis, system control and improvement. In this letter we present a computerized measurement system which is equipped with a hybrid, low-noise mechanical-electrical multiplexer for real-time two-dimensional (2D) mapping of surface temperatures. We demonstrate the performance of the system on a device embedded with 32 pieces of built-in Cr-Pt thin-film thermocouples arranged in a 4 × 8 matrix. The system can display a continuous 2D mapping movie of relative temperatures with a time interval around 1 s. This technique may find applications in a variety of practical devices and systems. PMID:27347969

  16. Real-Time Two-Dimensional Mapping of Relative Local Surface Temperatures with a Thin-Film Sensor Array.

    PubMed

    Li, Gang; Wang, Zhenhai; Mao, Xinyu; Zhang, Yinghuang; Huo, Xiaoye; Liu, Haixiao; Xu, Shengyong

    2016-06-25

    Dynamic mapping of an object's local temperature distribution may offer valuable information for failure analysis, system control and improvement. In this letter we present a computerized measurement system which is equipped with a hybrid, low-noise mechanical-electrical multiplexer for real-time two-dimensional (2D) mapping of surface temperatures. We demonstrate the performance of the system on a device embedded with 32 pieces of built-in Cr-Pt thin-film thermocouples arranged in a 4 × 8 matrix. The system can display a continuous 2D mapping movie of relative temperatures with a time interval around 1 s. This technique may find applications in a variety of practical devices and systems.

  17. Mapping surface tidal currents and Changjiang plume in the East China Sea from Geostationary Ocean Color Imager

    NASA Astrophysics Data System (ADS)

    Hu, Zifeng; Wang, Dong-Ping; Pan, Delu; He, Xianqiang; Miyazawa, Yasumasa; Bai, Yan; Wang, Difeng; Gong, Fang

    2016-03-01

    The spatial pattern of the semidiurnal M2 tidal currents in the East China Sea (ECS) is mapped from the Geostationary Ocean Color Imager (GOCI), taking advantage of the satellite's unique 8 hourly local daytime sequential images. The GOCI-derived surface M2 tidal currents are validated with a comprehensive set of twenty-eight surface drifters and four mooring observations. The agreement is outstanding with the error variance less than 10% of the total variance. The gridded GOCI-derived tidal currents are also in good agreement with the Oregon State University (OSU) high-resolution regional tidal model of the China Seas. The detided mean flow shows a strong Changjiang plume extending hundreds of kilometers offshore, in agreement with the concurrent satellite sea surface temperature (SST) and sea surface salinity (SSS) distributions. The observed surface currents are compared with the daily mean flows derived from the Japan Coastal Ocean Predictability Experiment (JCOPE2). The model results are consistent with the observations, showing the sensitivity of Changjiang plume to wind forcing. The study clearly demonstrates the utility of geostationary satellite in mapping the surface currents over a wide (˜400 km), tidally dominated continental shelf.

  18. World Map Showing Surface and Subsurface Distribution, and Lithologic Character of Middle and Late Neoproterozoic Rocks

    USGS Publications Warehouse

    Stewart, John H.

    2007-01-01

    INTRODUCTION The map was prepared to outline the basic information on where Neoproterozoic rocks are present in the World, and of the lithologic character of these rocks. The information provides a better understanding of major Neoproterozoic tectonic subdivisions useful in paleogeographic and plate tectonic reconstructions. The time frame of the map is within the middle and late Neoproterozoic from approximately 870 to 540 Ma and is after widespread Mesoproterozoic Grenville-age collisional events that are considered to have formed the hypothetical supercontinent of Rodinia. Much of the time represented by the map is interpreted to be during the fragmentation of Rodinia. The recognition of Neoproterozoic rocks is commonly difficult because of limited isotopic or paloeontological dating. Thus, some rocks shown on the map could be older or younger than the age indicated. However, at the scale of the map the the problem may be minor. Enough information seems to be available to indicate the general age of the rocks. Many of the successions contain diamictite deposits considered to be glaciogenic and dated as middle or late Neoproterozoic. These deposits thus show a rough correlation of middle and late Neoproterozoic rocks of the world. The map is a Richardson map projection, except for Antarctica which is a polar projection. The map was prepared from about 650 references, shown in the text linked below under 'Sources of Information', used to outline distribution patterns, determine rock types, and provide information on the regional and local geologic framework of the rocks. The focus of the references is on the geologic information needed to prepare the map. Other information, such as plate tectonic reconstructions or paleomagnetic studies is generally not included. The 'Sources of Information' lists references alphabetically for each of 14 regions. In brackets is a code for each area. These codes provide help in locating the specific regions in the references.

  19. Rapid quantitative chemical mapping of surfaces with sub-2 nm resolution.

    PubMed

    Lai, Chia-Yun; Perri, Saverio; Santos, Sergio; Garcia, Ricardo; Chiesa, Matteo

    2016-05-01

    We present a theory that exploits four observables in bimodal atomic force microscopy to produce maps of the Hamaker constant H. The quantitative H maps may be employed by the broader community to directly interpret the high resolution of standard bimodal AFM images as chemical maps while simultaneously quantifying chemistry in the non-contact regime. We further provide a simple methodology to optimize a range of operational parameters for which H is in the closest agreement with the Lifshitz theory in order to (1) simplify data acquisition and (2) generalize the methodology to any set of cantilever-sample systems.

  20. Surface Temperature Mapping of the University of Northern Iowa Campus Using High Resolution Thermal Infrared Aerial Imageries

    PubMed Central

    Savelyev, Alexander; Sugumaran, Ramanathan

    2008-01-01

    The goal of this project was to map the surface temperature of the University of Northern Iowa campus using high-resolution thermal infrared aerial imageries. A thermal camera with a spectral bandwidth of 3.0-5.0 μm was flown at the average altitude of 600 m, achieving ground resolution of 29 cm. Ground control data was used to construct the pixel- to-temperature conversion model, which was later used to produce temperature maps of the entire campus and also for validation of the model. The temperature map then was used to assess the building rooftop conditions and steam line faults in the study area. Assessment of the temperature map revealed a number of building structures that may be subject to insulation improvement due to their high surface temperatures leaks. Several hot spots were also identified on the campus for steam pipelines faults. High-resolution thermal infrared imagery proved highly effective tool for precise heat anomaly detection on the campus, and it can be used by university facility services for effective future maintenance of buildings and grounds.

  1. Development of a Silicon Drift Detector Array: An X-Ray Fluorescence Spectrometer for Remote Surface Mapping

    NASA Technical Reports Server (NTRS)

    Gaskin, Jessica A.; Carini, Gabriella A.; Wei, Chen; Elsner, Ronald F.; Kramer, Georgiana; De Geronimo, Gianluigi; Keister, Jeffrey W.; Zheng, Li; Ramsey, Brian D.; Rehak, Pavel; Siddons, D. Peter

    2009-01-01

    Over the past three years NASA Marshall Space Flight Center has been collaborating with Brookhaven National Laboratory to develop a modular Silicon Drift Detector (SDD) X-Ray Spectrometer (XRS) intended for fine surface mapping of the light elements of the moon. The value of fluorescence spectrometry for surface element mapping is underlined by the fact that the technique has recently been employed by three lunar orbiter missions; Kaguya, Chandrayaan-1, and Chang e. The SDD-XRS instrument we have been developing can operate at a low energy threshold (i.e. is capable of detecting Carbon), comparable energy resolution to Kaguya (<150 eV at 5.9 keV) and an order of magnitude lower power requirement, making much higher sensitivities possible. Furthermore, the intrinsic radiation resistance of the SDD makes it useful even in radiation-harsh environments such as that of Jupiter and its surrounding moons.

  2. Mapping the Potential for Eolian Surface Activity in Grasslands of the High Plains using Landsat Images

    NASA Technical Reports Server (NTRS)

    Gutmann, Ethan Dain

    2002-01-01

    There are over 100,000 square kilometers of eolian sand dunes and sand sheets in the High Plains of the central United States. These land-forms may be unstable and may reactivate again as a result of land-use, climate change, or natural climatic variability. The main goal of this thesis was to develop a model that could be used to map an estimate of future dune activity. Multi-temporal calibrated Landsats 5 Thematic Mapper (TM) and 7 Enhanced Thematic Map per Plus (ETM+) NDVI imagery were used in conjunction with the CENTURY vegetation model to correlate vegetation cover to climatic variability. This allows the creation of a predicted vegetation map which, combined with current wind and soil data, was used to create a potential sand transport map for range land in the High Plains under drought conditions.

  3. Hydrogeological Mapping and Hydrological Process Modelling for understanding the interaction of surface runoff and infiltration in a karstic catchment

    NASA Astrophysics Data System (ADS)

    Stadler, Hermann; Reszler, Christian; Komma, Jürgen; Poltnig, Walter; Strobl, Elmar; Blöschl, Günter

    2013-04-01

    This paper presents a study at the interface hydrogeology - hydrology, concerning mapping of surface runoff generation areas in a karstic catchment. The governing processes range from surface runoff with subsequent infiltration to direct infiltration and further deep percolation into different karst conduits. The aim is to identify areas with a potential of surface erosion and thus, identify the hazard of solute/contaminant input into the karst system during aestival thundershowers, which can affect water quality at springs draining the karst massif. According to hydrogeological methods the emphasis of the study are field investigations based on hydrogeological mapping and field measurements in order to gain extensive knowledge about processes and their spatial distribution in the catchment to establish a site specific Dominant Process Concept (DPC). Based on the hydrogeological map, which describes the lithological units relating to their hydrogeological classification, mapping focuses on the following attributes of the overlaying loose material/debris and soils: (i) infiltration capability, (ii) soil depth (as a measure for storage capacity), and (iii) potential surface flow length. Detailed mapping is performed in the reference area, where a variety of data are acquired, such as soil grain size distribution, soil moisture through TDR measurements at characteristic points, etc. The reference area borders both end-members of the dominant surface runoff processes as described above. Geomorphologic analyses based on a 1m resolution Laserscan assist in allocating sinks and flow accumulation paths in the catchment. By a regionalisation model, developed and calibrated based on the results in the reference areas, the process disposition is transposed onto the whole study area. In a further step, a hydrological model will be set up, where model structure and parameters are identified based on above described working steps and following the DPC. The model will be

  4. Rapid quantitative chemical mapping of surfaces with sub-2 nm resolution

    NASA Astrophysics Data System (ADS)

    Lai, Chia-Yun; Perri, Saverio; Santos, Sergio; Garcia, Ricardo; Chiesa, Matteo

    2016-05-01

    We present a theory that exploits four observables in bimodal atomic force microscopy to produce maps of the Hamaker constant H. The quantitative H maps may be employed by the broader community to directly interpret the high resolution of standard bimodal AFM images as chemical maps while simultaneously quantifying chemistry in the non-contact regime. We further provide a simple methodology to optimize a range of operational parameters for which H is in the closest agreement with the Lifshitz theory in order to (1) simplify data acquisition and (2) generalize the methodology to any set of cantilever-sample systems.We present a theory that exploits four observables in bimodal atomic force microscopy to produce maps of the Hamaker constant H. The quantitative H maps may be employed by the broader community to directly interpret the high resolution of standard bimodal AFM images as chemical maps while simultaneously quantifying chemistry in the non-contact regime. We further provide a simple methodology to optimize a range of operational parameters for which H is in the closest agreement with the Lifshitz theory in order to (1) simplify data acquisition and (2) generalize the methodology to any set of cantilever-sample systems. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr00496b

  5. Surface Ruptures and Building Damage of the 2003 Bam, Iran, Earthquake Mapped by Satellite Synthetic Aperture Radar Interferometric Correlation

    NASA Technical Reports Server (NTRS)

    Fielding, Eric J.; Talebian, M.; Rosen, P. A.; Nazari, H.; Jackson, J. A.; Ghorashi, M.; Walker, R.

    2005-01-01

    We use the interferometric correlation from Envisat synthetic aperture radar (SAR) images to map the details of the surface ruptures related to the 26 December 2003 earthquake that devastated Bam, Iran. The main strike-slip fault rupture south of the city of Bam has a series of four segments with left steps shown by a narrow line of low correlation in the coseismic interferogram. This also has a clear expression in the field because of the net extension across the fault. Just south of the city limits, the surface strain becomes distributed over a width of about 500 m, probably because of a thicker layer of soft sedimentary material.

  6. Synergistic use of optical and InSAR data for urban impervious surface mapping: A case study in Hong Kong

    USGS Publications Warehouse

    Jiang, L.; Liao, M.; Lin, H.; Yang, L.

    2009-01-01

    A wide range of urban ecosystem studies, including urban hydrology, urban climate, land use planning and watershed resource management, require accurate and up-to-date geospatial data of urban impervious surfaces. In this study, the potential of the synergistic use of optical and InSAR data in urban impervious surface mapping at the sub-pixel level was investigated. A case study in Hong Kong was conducted for this purpose by applying a classification and regression tree (CART) algorithm to SPOT 5 multispectral imagery and ERS-2 SAR data. Validated by reference data derived from high-resolution colour-infrared (CIR) aerial photographs, our results show that the addition of InSAR feature information can improve the estimation of impervious surface percentage (ISP) in comparison with using SPOT imagery alone. The improvement is especially notable in separating urban impervious surface from the vacant land/bare ground, which has been a difficult task in ISP modelling with optical remote sensing data. In addition, the results demonstrate the potential to map urban impervious surface by using InSAR data alone. This allows frequent monitoring of world's cities located in cloud-prone and rainy areas. ?? 2009 Taylor & Francis.

  7. Mapping land water and energy balance relations through conditional sampling of remote sensing estimates of atmospheric forcing and surface states

    NASA Astrophysics Data System (ADS)

    Farhadi, Leila; Entekhabi, Dara; Salvucci, Guido

    2016-04-01

    In this study, we develop and apply a mapping estimation capability for key unknown parameters that link the surface water and energy balance equations. The method is applied to the Gourma region in West Africa. The accuracy of the estimation method at point scale was previously examined using flux tower data. In this study, the capability is scaled to be applicable with remotely sensed data products and hence allow mapping. Parameters of the system are estimated through a process that links atmospheric forcing (precipitation and incident radiation), surface states, and unknown parameters. Based on conditional averaging of land surface temperature and moisture states, respectively, a single objective function is posed that measures moisture and temperature-dependent errors solely in terms of observed forcings and surface states. This objective function is minimized with respect to parameters to identify evapotranspiration and drainage models and estimate water and energy balance flux components. The uncertainty of the estimated parameters (and associated statistical confidence limits) is obtained through the inverse of Hessian of the objective function, which is an approximation of the covariance matrix. This calibration-free method is applied to the mesoscale region of Gourma in West Africa using multiplatform remote sensing data. The retrievals are verified against tower-flux field site data and physiographic characteristics of the region. The focus is to find the functional form of the evaporative fraction dependence on soil moisture, a key closure function for surface and subsurface heat and moisture dynamics, using remote sensing data.

  8. A Unique Procedure to Identify Cell Surface Markers Through a Spherical Self-Organizing Map Applied to DNA Microarray Analysis.

    PubMed

    Sugii, Yuh; Kasai, Tomonari; Ikeda, Masashi; Vaidyanath, Arun; Kumon, Kazuki; Mizutani, Akifumi; Seno, Akimasa; Tokutaka, Heizo; Kudoh, Takayuki; Seno, Masaharu

    2016-01-01

    To identify cell-specific markers, we designed a DNA microarray platform with oligonucleotide probes for human membrane-anchored proteins. Human glioma cell lines were analyzed using microarray and compared with normal and fetal brain tissues. For the microarray analysis, we employed a spherical self-organizing map, which is a clustering method suitable for the conversion of multidimensional data into two-dimensional data and displays the relationship on a spherical surface. Based on the gene expression profile, the cell surface characteristics were successfully mirrored onto the spherical surface, thereby distinguishing normal brain tissue from the disease model based on the strength of gene expression. The clustered glioma-specific genes were further analyzed by polymerase chain reaction procedure and immunocytochemical staining of glioma cells. Our platform and the following procedure were successfully demonstrated to categorize the genes coding for cell surface proteins that are specific to glioma cells. Our assessment demonstrates that a spherical self-organizing map is a valuable tool for distinguishing cell surface markers and can be employed in marker discovery studies for the treatment of cancer.

  9. A Unique Procedure to Identify Cell Surface Markers Through a Spherical Self-Organizing Map Applied to DNA Microarray Analysis

    PubMed Central

    Sugii, Yuh; Kasai, Tomonari; Ikeda, Masashi; Vaidyanath, Arun; Kumon, Kazuki; Mizutani, Akifumi; Seno, Akimasa; Tokutaka, Heizo; Kudoh, Takayuki; Seno, Masaharu

    2016-01-01

    To identify cell-specific markers, we designed a DNA microarray platform with oligonucleotide probes for human membrane-anchored proteins. Human glioma cell lines were analyzed using microarray and compared with normal and fetal brain tissues. For the microarray analysis, we employed a spherical self-organizing map, which is a clustering method suitable for the conversion of multidimensional data into two-dimensional data and displays the relationship on a spherical surface. Based on the gene expression profile, the cell surface characteristics were successfully mirrored onto the spherical surface, thereby distinguishing normal brain tissue from the disease model based on the strength of gene expression. The clustered glioma-specific genes were further analyzed by polymerase chain reaction procedure and immunocytochemical staining of glioma cells. Our platform and the following procedure were successfully demonstrated to categorize the genes coding for cell surface proteins that are specific to glioma cells. Our assessment demonstrates that a spherical self-organizing map is a valuable tool for distinguishing cell surface markers and can be employed in marker discovery studies for the treatment of cancer. PMID:26966393

  10. XML-BSPM: an XML format for storing Body Surface Potential Map recordings

    PubMed Central

    2010-01-01

    Background The Body Surface Potential Map (BSPM) is an electrocardiographic method, for recording and displaying the electrical activity of the heart, from a spatial perspective. The BSPM has been deemed more accurate for assessing certain cardiac pathologies when compared to the 12-lead ECG. Nevertheless, the 12-lead ECG remains the most popular ECG acquisition method for non-invasively assessing the electrical activity of the heart. Although data from the 12-lead ECG can be stored and shared using open formats such as SCP-ECG, no open formats currently exist for storing and sharing the BSPM. As a result, an innovative format for storing BSPM datasets has been developed within this study. Methods The XML vocabulary was chosen for implementation, as opposed to binary for the purpose of human readability. There are currently no standards to dictate the number of electrodes and electrode positions for recording a BSPM. In fact, there are at least 11 different BSPM electrode configurations in use today. Therefore, in order to support these BSPM variants, the XML-BSPM format was made versatile. Hence, the format supports the storage of custom torso diagrams using SVG graphics. This diagram can then be used in a 2D coordinate system for retaining electrode positions. Results This XML-BSPM format has been successfully used to store the Kornreich-117 BSPM dataset and the Lux-192 BSPM dataset. The resulting file sizes were in the region of 277 kilobytes for each BSPM recording and can be deemed suitable for example, for use with any telemonitoring application. Moreover, there is potential for file sizes to be further reduced using basic compression algorithms, i.e. the deflate algorithm. Finally, these BSPM files have been parsed and visualised within a convenient time period using a web based BSPM viewer. Conclusions This format, if widely adopted could promote BSPM interoperability, knowledge sharing and data mining. This work could also be used to provide conceptual

  11. Surface Electrical Conductivity Prediction by Soil Moisture and Electromagnetic Mapping Techniques: Implication for Landmine Detection Technologies

    NASA Astrophysics Data System (ADS)

    Katsube, J.; McNairn, H.; Keating, P. K.; Das, Y.; Dyke, L.; Best, M. E.; Singhroy, V.; Connell-Madore, S.; Hunter, J.; Klassen, R.; Dilabio, R.; Moore, A.

    2004-05-01

    Electrical conductivity (EC) can be a source of significant signal interference in landmine detection, implying that there is a necessity for soil EC prediction in order to carry out safe demining operations in landmine affected countries in the world. A fundamental study on soil EC mechanisms and their relationship to moisture content has been carried out in order to increase the soil EC prediction accuracy when using data from various sensors, such as remote sensing, airborne and surficial electromagnetic (EM) methods. Results indicate that soil moisture consists of free water filling pore spaces and bound water which forms adsorbed water layers on the grain surfaces. The response of these two water phases to drying rates and EC are very different, to the extent that a moist clay poor soil may have low EC but a dry clay rich soil may have higher EC. This is a result of not only the bound water layers being a significant source of EC, but of the capillary component of the free water reacting differently to the different grain-sizes of the soil. The capillary water forms important electrical conductive bridges between the adsorbed water layers on the grains that constitute the soil. This implies that information on soil texture, mineralogy and their distribution are required for accurate EC prediction. Whereas information on these soil characteristics may be acquired by remote sensing and soil maps, soil moisture content is likely to vary from the time of data acquisition to that of demining operations, implying methods to predict these changes are required. In addition, soil type inhomogeniety, such as vertical and horizontal variation can also be a source of inaccuracies in moisture and EC predictions. However, these investigations also indicate that a wide band electrical frequency signal may have the possibility of providing information on, not only metallic mineral content, but on pore space, clay mineral type and water content. In addition, applications of

  12. Mapping surface disturbance of energy-related infrastructure in southwest Wyoming--An assessment of methods

    USGS Publications Warehouse

    Germaine, Stephen S.; O'Donnell, Michael S.; Aldridge, Cameron L.; Baer, Lori; Fancher, Tammy; McBeth, Jamie; McDougal, Robert R.; Waltermire, Robert; Bowen, Zachary H.; Diffendorfer, James; Garman, Steven; Hanson, Leanne

    2012-01-01

    We evaluated how well three leading information-extraction software programs (eCognition, Feature Analyst, Feature Extraction) and manual hand digitization interpreted information from remotely sensed imagery of a visually complex gas field in Wyoming. Specifically, we compared how each mapped the area of and classified the disturbance features present on each of three remotely sensed images, including 30-meter-resolution Landsat, 10-meter-resolution SPOT (Satellite Pour l'Observation de la Terre), and 0.6-meter resolution pan-sharpened QuickBird scenes. Feature Extraction mapped the spatial area of disturbance features most accurately on the Landsat and QuickBird imagery, while hand digitization was most accurate on the SPOT imagery. Footprint non-overlap error was smallest on the Feature Analyst map of the Landsat imagery, the hand digitization map of the SPOT imagery, and the Feature Extraction map of the QuickBird imagery. When evaluating feature classification success against a set of ground-truthed control points, Feature Analyst, Feature Extraction, and hand digitization classified features with similar success on the QuickBird and SPOT imagery, while eCognition classified features poorly relative to the other methods. All maps derived from Landsat imagery classified disturbance features poorly. Using the hand digitized QuickBird data as a reference and making pixel-by-pixel comparisons, Feature Extraction classified features best overall on the QuickBird imagery, and Feature Analyst classified features best overall on the SPOT and Landsat imagery. Based on the entire suite of tasks we evaluated, Feature Extraction performed best overall on the Landsat and QuickBird imagery, while hand digitization performed best overall on the SPOT imagery, and eCognition performed worst overall on all three images. Error rates for both area measurements and feature classification were prohibitively high on Landsat imagery, while QuickBird was time and cost prohibitive for

  13. Hydrated salt minerals on Europa's Surface from the Galileo near-infrared mapping spectrometer (NIMS) investigation

    USGS Publications Warehouse

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

    1999-01-01

    We reported evidence of heavily hydrated salt minerals present over large areas of Europa's surface from analysis of reflectance spectra returned by the Galileo mission near infrared mapping spectrometer (NIMS) [McCord et al., 1997a, b, 1998a, b]. Here we elaborate on this earlier evidence, present spatial distributions of these minerals, examine alternate water-ice interpretations, expand on our hydrated-salts interpretation, consider salt mineral stability on Europa, and discuss the implications. Extensive well-defined areas on Europa show distinct, asymmetric water-related absorption bands in the 1 to 2.5-??m region. Radiative transfer modeling of water ice involving different particle sizes and layers at Europa temperatures does not reproduce the distinctive Europa water bands. However, ice near its melting temperature, such as in terrestrial environments, does have some characteristics of the Europa spectrum. Alternatively, some classes of heavily hydrated minerals do exhibit such water bands. Among plausible materials, heavily hydrated salt minerals, such as magnesium and sodium sulfates, sodium carbonate and their mixtures, are preferred. All Europa spectral features are present in some salt minerals and a very good match to the Europa spectrum can be achieved by mixing several salt spectra. However, no single or mix of salt mineral spectra from the limited library available has so far been found to perfectly match the Europa spectrum in every detail. The material is concentrated at the lineaments and in chaotic terrain, which are technically disrupted areas on the trailing side. Since the spectrum of the material on Europa is nearly the same everywhere so-far studied, the salt or salt-mixture composition may be nearly uniform. This suggests similar sources and processes over at least a near-hemispheric scale. This would suggest that an extensive subsurface ocean containing dissolved salts is the source, and several possible mechanisms for deposit

  14. Mapping and Assessing Surface Morphology of Holocene Lava Field in Krafla (NE Iceland) Using Hyperspectral Remote Sensing

    NASA Astrophysics Data System (ADS)

    Aufaristama, M.; Höskuldsson, A.; Jónsdóttir, I.; Ólafsdóttir, R.

    2016-01-01

    Iceland is well known for its volcanic activity due to its location on the spreading Mid Atlantic Ridge and one of the earth's hot spot. In the past 1000 years there were about 200 eruptions occurring in Iceland, meaning volcanic eruptions occurred every four to five years, on average. Iceland currently has 30 active volcano systems, distributed evenly throughout the so- called Neovolcanic Zone. One of these volcanic systems is the Krafla central volcano, which is located in the northern Iceland at latitude 65°42'53'' N and longitude 16°43'40'' W. Krafla has produced two volcanic events in historic times: 1724-1729 (Myvatn Fires) and 1975-1984 (Krafla Fires). The Krafla Fires began in December 1975 and lasted until September 1984. This event covered about 36-km2 surrounding area with lava, having a total volume of 0.25-0.3 km3. Previous studies of lava surface morphology at Krafla focused on an open channel area by remote sensing are essential as a complementary tool to the previous investigations and to extend the area of mapping. Using Spectral Angle Mapper (SAM) classification approach by selecting spectral reflectance end members, this study has successfully produced a detailed map of the surface morphology in Krafla lava field EO-1 Hyperion (Hyperspectral) satellite images. The overall accuracy of lava morphology map is 61.33% (EO-1 Hyperion). These results show that hyperspectral remote sensing is an acceptable alternative to field mapping and assessing the lava surface morphology in the Krafla lava field. In order to get validation of the satellite image's spectral reflectance, in-situ measurements of the lava field's spectral reflectance using ASD FieldSpec3 is essential.

  15. MODELING THE ANOMALY OF SURFACE NUMBER DENSITIES OF GALAXIES ON THE GALACTIC EXTINCTION MAP DUE TO THEIR FIR EMISSION CONTAMINATION

    SciTech Connect

    Kashiwagi, Toshiya; Suto, Yasushi; Taruya, Atsushi; Yahata, Kazuhiro; Kayo, Issha; Nishimichi, Takahiro

    2015-02-01

    The most widely used Galactic extinction map is constructed assuming that the observed far-infrared (FIR) fluxes come entirely from Galactic dust. According to the earlier suggestion by Yahata et al., we consider how FIR emission of galaxies affects the SFD map. We first compute the surface number density of Sloan Digital Sky Survey (SDSS) DR7 galaxies as a function of the r-band extinction, A {sub r,} {sub SFD}. We confirm that the surface densities of those galaxies positively correlate with A {sub r,} {sub SFD} for A {sub r,} {sub SFD} < 0.1, as first discovered by Yahata et al. for SDSS DR4 galaxies. Next we construct an analytical model to compute the surface density of galaxies, taking into account the contamination of their FIR emission. We adopt a log-normal probability distribution for the ratio of 100 μm and r-band luminosities of each galaxy, y ≡ (νL){sub 100} {sub μm}/(νL) {sub r}. Then we search for the mean and rms values of y that fit the observed anomaly, using the analytical model. The required values to reproduce the anomaly are roughly consistent with those measured from the stacking analysis of SDSS galaxies. Due to the limitation of our statistical modeling, we are not yet able to remove the FIR contamination of galaxies from the extinction map. Nevertheless, the agreement with the model prediction suggests that the FIR emission of galaxies is mainly responsible for the observed anomaly. Whereas the corresponding systematic error in the Galactic extinction map is 0.1-1 mmag, it is directly correlated with galaxy clustering and thus needs to be carefully examined in precision cosmology.

  16. A semi-automatic multiple view texture mapping for the surface model extracted by laser scanning

    NASA Astrophysics Data System (ADS)

    Zhang, Zhichao; Huang, Xianfeng; Zhang, Fan; Chang, Yongmin; Li, Deren

    2008-12-01

    Laser scanning is an effective way to acquire geometry data of the cultural heritage with complex architecture. After generating the 3D model of the object, it's difficult to do the exactly texture mapping for the real object. we take effort to create seamless texture maps for a virtual heritage of arbitrary topology. Texture detail is acquired directly from the real object in a light condition as uniform as we can make. After preprocessing, images are then registered on the 3D mesh by a semi-automatic way. Then we divide the mesh into mesh patches overlapped with each other according to the valid texture area of each image. An optimal correspondence between mesh patches and sections of the acquired images is built. Then, a smoothing approach is proposed to erase the seam between different images that map on adjacent mesh patches, based on texture blending. The obtained result with a Buddha of Dunhuang Mogao Grottoes is presented and discussed.

  17. Mapping Porosity Structure Offshore Torrey Pines State Natural Reserve and Del Mar, California Using a Surface Towed EM System

    NASA Astrophysics Data System (ADS)

    Martin, Thomas Patrick

    Controlled source electromagnetic methods have been used in exploration of the offshore environment for over 50 years to map the resistivity structure of the earth. Developments in both instrumentation and computational power have lead to many advancements that have led to discoveries and insights about the subsurface. One of these advancements has been the development of towed EM acquisition systems. One system the Marine EM Lab at Scripps Institution of Oceanography has developed is a shallow water system, named Porpoise, can be used in water depths as shallow as 5m. In May of 2014, a one day field test of this new shallow water acquisition system took place offshore of Del Mar and Torrey Pines State Natural Reserve, California. The data from this field test corresponds with previous interpretations of paleochannels directly offshore modern day San Dieguito and Soledad Valley river outflows. With resistivity data, it is possible to indirectly map porosity in the near surface and to map geological features. The data dense and economical operation of the Porpoise acquisition system can be used to map resistivity and indirectly porosity in a variety of shallow water marine environments. This field test proves the viability and limitations of the Porpoise system.

  18. Surface-Enhanced Raman Spectroscopy Based Quantitative Bioassay on Aptamer-Functionalized Nanopillars Using Large-Area Raman Mapping

    PubMed Central

    Yang, Jaeyoung; Palla, Mirko; Bosco, Filippo Giacomo; Rindzevicius, Tomas; Alstrøm, Tommy Sonne; Schmidt, Michael Stenbæk; Boisen, Anja; Ju, Jingyue; Lin, Qiao

    2013-01-01

    Surface-enhanced Raman spectroscopy (SERS) has been used in a variety of biological applications due to its high sensitivity and specificity. Here, we report a SERS-based biosensing approach for quantitative detection of biomolecules. A SERS substrate bearing gold-decorated silicon nanopillars is functionalized with aptamers for sensitive and specific detection of target molecules. In this study, TAMRA-labeled vasopressin molecules in the picomolar regime (1 pM to 1 nM) are specifically captured by aptamers on the nanostructured SERS substrate and monitored by using an automated SERS signal mapping technique. From the experimental results, we show concentration-dependent SERS responses in the picomolar range by integrating SERS signal intensities over a scanning area. It is also noted that our signal mapping approach significantly improves statistical reproducibility and accounts for spot-to-spot variation in conventional SERS quantification. Furthermore, we have developed an analytical model capable of predicting experimental intensity distributions on the substrates for reliable quantification of biomolecules. Lastly, we have calculated the minimum needed area of Raman mapping for efficient and reliable analysis of each measurement. Combining our SERS mapping analysis with an aptamer-functionalized nanopillar substrate is found to be extremely efficient for detection of low-abundance biomolecules. PMID:23713574

  19. Molecular-scale investigations of structures and surface charge distribution of surfactant aggregates by three-dimensional force mapping

    SciTech Connect

    Suzuki, Kazuhiro; Oyabu, Noriaki; Matsushige, Kazumi; Yamada, Hirofumi; Kobayashi, Kei

    2014-02-07

    Surface charges on nanoscale structures in liquids, such as biomolecules and nano-micelles, play an essentially important role in their structural stability as well as their chemical activities. These structures interact with each other through electric double layers (EDLs) formed by the counter ions in electrolyte solution. Although static-mode atomic force microscopy (AFM) including colloidal-probe AFM is a powerful technique for surface charge density measurements and EDL analysis on a submicron scale in liquids, precise surface charge density analysis with single-nanometer resolution has not been made because of its limitation of the resolution and the detection sensitivity. Here we demonstrate molecular-scale surface charge measurements of self-assembled micellar structures, molecular hemicylinders of sodium dodecyl sulfate (SDS), by three-dimensional (3D) force mapping based on frequency modulation AFM. The SDS hemicylindrical structures with a diameter of 4.8 nm on a graphite surface were clearly imaged. We have succeeded in visualizing 3D EDL forces on the SDS hemicylinder surfaces and obtaining the molecular-scale charge density for the first time. The results showed that the surface charge on the trench regions between the hemicylinders was much smaller than that on the hemicylinder tops. The method can be applied to a wide variety of local charge distribution studies, such as spatial charge variation on a single protein molecule.

  20. Lunar Far-UV Dayside Albedo Maps: LRO/LAMP Investigations of Surface Hydration and Space Weathering

    NASA Astrophysics Data System (ADS)

    Retherford, Kurt D.; Hendrix, A. R.; Gladstone, G. R.; Stern, S. A.; Miles, P. F.; Egan, A. F.; Kaufmann, D. E.; Feldman, P. D.; Hurley, D. M.; Greathouse, T. K.; Parker, J. W.; Bayless, A. J.; Davis, M. W.; Cook, J. C.; Mukherjee, J.

    2012-10-01

    The Lyman Alpha Mapping Project (LAMP) is an ultraviolet (UV) spectrograph on the Lunar Reconnaissance Orbiter (LRO) that is currently mapping the lunar albedo at far-UV wavelengths. LAMP primarily measures faint interplanetary HI Lyman-alpha sky-glow and far-UV starlight reflected from the nightside lunar surface to pioneer an innovative technique for studying the permanently shadowed regions (PSRs) near the poles. Far-UV reflectance measurements of the bright lunar dayside are also frequently obtained. LAMP dayside measurements utilize a "pinhole" aperture with a factor of 736 less throughput to obtain a comparable dynamic range of detector count rates as for the nightside measurements. Initial spectral analysis of broad ( 10 deg latitude) regions within the dayside dataset indicate evidence for latitudinal and diurnal trends that are diagnostic of surface hydration and space weathering, as reported by Hendrix et al. 2012. We report initial results from follow on analyses of high spatial resolution maps produced using the LAMP dayside reflectance dataset.

  1. Usefulness of ventricular endocardial electric reconstruction from body surface potential maps to noninvasively localize ventricular ectopic activity in patients

    NASA Astrophysics Data System (ADS)

    Lai, Dakun; Sun, Jian; Li, Yigang; He, Bin

    2013-06-01

    As radio frequency (RF) catheter ablation becomes increasingly prevalent in the management of ventricular arrhythmia in patients, an accurate and rapid determination of the arrhythmogenic site is of important clinical interest. The aim of this study was to test the hypothesis that the inversely reconstructed ventricular endocardial current density distribution from body surface potential maps (BSPMs) can localize the regions critical for maintenance of a ventricular ectopic activity. Patients with isolated and monomorphic premature ventricular contractions (PVCs) were investigated by noninvasive BSPMs and subsequent invasive catheter mapping and ablation. Equivalent current density (CD) reconstruction (CDR) during symptomatic PVCs was obtained on the endocardial ventricular surface in six patients (four men, two women, years 23-77), and the origin of the spontaneous ectopic activity was localized at the location of the maximum CD value. Compared with the last (successful) ablation site (LAS), the mean and standard deviation of localization error of the CDR approach were 13.8 and 1.3 mm, respectively. In comparison, the distance between the LASs and the estimated locations of an equivalent single moving dipole in the heart was 25.5 ± 5.5 mm. The obtained CD distribution of activated sources extending from the catheter ablation site also showed a high consistency with the invasively recorded electroanatomical maps. The noninvasively reconstructed endocardial CD distribution is suitable to predict a region of interest containing or close to arrhythmia source, which may have the potential to guide RF catheter ablation.

  2. Noninvasive Imaging of Human Atrial Activation during Atrial Flutter and Normal Rhythm from Body Surface Potential Maps

    PubMed Central

    Zhou, Zhaoye; Jin, Qi; Yu, Long; Wu, Liqun; He, Bin

    2016-01-01

    Background Knowledge of atrial electrophysiological properties is crucial for clinical intervention of atrial arrhythmias and the investigation of the underlying mechanism. This study aims to evaluate the feasibility of a novel noninvasive cardiac electrical imaging technique in imaging bi-atrial activation sequences from body surface potential maps (BSPMs). Methods The study includes 7 subjects, with 3 atrial flutter patients, and 4 healthy subjects with normal atrial activations. The subject-specific heart-torso geometries were obtained from MRI/CT images. The equivalent current densities were reconstructed from 208-channel BSPMs by solving the inverse problem using individual heart-torso geometry models. The activation times were estimated from the time instant corresponding to the highest peak in the time course of the equivalent current densities. To evaluate the performance, a total of 32 cycles of atrial flutter were analyzed. The imaged activation maps obtained from single beats were compared with the average maps and the activation maps measured from CARTO, by using correlation coefficient (CC) and relative error (RE). Results The cardiac electrical imaging technique is capable of imaging both focal and reentrant activations. The imaged activation maps for normal atrial activations are consistent with findings from isolated human hearts. Activation maps for isthmus-dependent counterclockwise reentry were reconstructed on three patients with typical atrial flutter. The method was capable of imaging macro counterclockwise reentrant loop in the right atrium and showed inter-atria electrical conduction through coronary sinus. The imaged activation sequences obtained from single beats showed good correlation with both the average activation maps (CC = 0.91±0.03, RE = 0.29±0.05) and the clinical endocardial findings using CARTO (CC = 0.70±0.04, RE = 0.42±0.05). Conclusions The noninvasive cardiac electrical imaging technique is able to reconstruct complex

  3. Rapid Semi-Quantitative Surface Mapping of Airborne-Dispersed Chemicals Using Mass Spectrometry

    EPA Science Inventory

    Chemicals can be dispersed accidentally, deliberately, or by weather-related events. Rapid mapping of contaminant distributions is necessary to assess exposure risks and to plan remediation, when needed. Ten pulverized aspirin or NoDozTM tablets containing caffeine wer...

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

    ERIC Educational Resources Information Center

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

    2014-01-01

    Previous work has shown that toddlers readily encode each noun in the sentence as a distinct argument of the verb. However, languages allow multiple mappings between form and meaning that do not fit this canonical format. Two experiments examined French 28-month-olds' interpretation of right-dislocated sentences ("noun"-verb,…

  5. Surface Energy Balance Based Evapotranspiration Mapping in the Texas High Plains

    PubMed Central

    Gowda, Prasanna H.; Chávez, José L.; Howell, Terry A.; Marek, Thomas H.; New, Leon L.

    2008-01-01

    Agriculture on the Texas High Plains (THP) uses approximately 89% of groundwater withdrawals from the Ogallala Aquifer. Consequently, groundwater levels are declining faster than the recharge rate. Therefore, efficient agricultural water use is essential for economic viability and sustainability of the THP. Accurate regional evapotranspiration (ET) maps would provide valuable information on actual crop water use. In this study, METRIC (Mapping Evapotranspiration at High Resolution using Internalized Calibration), a remote sensing based ET algorithm, was evaluated for mapping ET in the THP. Two Landsat 5 Thematic Mapper images acquired on 27 June (DOY 178) and 29 July (DOY 210) 2005 were used for this purpose. The performance of the ET model was evaluated by comparing the predicted daily ET with values derived from soil moisture budget at four commercial agricultural fields. Daily ET estimates resulted with a prediction error of 12.7±8.1% (mean bias error ± root mean square error) on DOY 178 and -4.7±9.4% on DOY 210 when compared with ET derived from measured soil moisture through the soil water balance. These results are good considering the prevailing advective conditions in the THP. METRIC have the potential to be used for mapping regional ET in the THP region. However, more evaluation is needed under different agroclimatological conditions.

  6. Developed Design for Humeral Head Replacement Using 3D Surface Mapping

    NASA Astrophysics Data System (ADS)

    Salah, H. R.

    2014-12-01

    Assessment of dimensional and geometrical data on the humeral head replacement (HHR) objects is essential for solving the relevant designing problems in the physics of reverse engineering (RE). In this work, 2D-assessment for human humerus was performed using the computed tomography (CT) technique within the RE plan, after which the 2D images of humeral objects were converted into 3D images. The conversion was successful and indicated a clear difference in the 2D and 3D estimates of sizes and geometry of the humerus. The authors have analyzed and confirmed experimentally the statistical information on the relevant anatomical objects. The results of finite-element simulation of the compressive stresses affecting the geometry of 3D surface mapping were analyzed using SolidWorks software. For developing the biomechanical design of an HHR object suitable biomaterials were selected, and different metal-based biomaterials are discussed as applied at various loads. New methodology is presented for the size estimation of humeral head - both anatomical and artificial - in 3D-shape. A detailed interpretation is given for the results of CT D-measurements. Izmēru un ģeometrisko datu novērtējums, kas attiecas uz pleca kaula galviņas nomaiņas (PKGN) objektiem, nepieciešams, lai risinātu virkni reversīvās inženierijas (RI) problēmu. Šajā darbā cilvēka pleca kaula galviņas divdimensiju novērtējums tika veikts ar datortomogrāfijas palīdzību (RI) ietvaros, un pēc tam objekta divdimensiju attēlojums tika pārveidots trīsdimensiju. Pārveidojums bija sekmīgs, parādot pleca kaula galviņas izmēru un ģeometrijas atšķirības starp 2D un 3D novērtējumiem. Autori izanalizēja un eksperimentāli apstiprināja statistisko informāciju pēc dotā veida anatomiskiem objektiem. Saspiešanas sasprindzinājumi, kuri ietekmē trīsdimensiju virsmas attēlojuma ģeometriju, tika analizēti ar gala-elementu simulācijas metodi, lietojot programmu Solid

  7. Reciprocal space XRD mapping with varied incident angle as a probe of structure variation within surface depth

    SciTech Connect

    Yang, Qiguang; Williams, Frances; Zhao, Xin; Reece, Charles E.; Krishnan, Mahadevan

    2013-09-01

    In this study, we used a differential-depth X-Ray diffraction Reciprocal Spacing Mapping (XRD RSM) technique to investigate the crystal quality of a variety of SRF-relevant Nb film and bulk materials. By choosing different X-ray probing depths, the RSM study successfully revealed evolution the of materials microstructure after different materials processes, such as energetic condensation or surface polishing. The RSM data clearly measured the materials crystal quality at different thickness. Through a novel differential-depth RSM technique, this study found: I. for a heteroepitaxy Nb film Nb(100)/MgO(100), the film thickening process, via a cathodic arc-discharge Nb ion deposition, created a near-perfect single crystal Nb on the surfaces top-layer; II. for a mechanically polished single-crystal bulk Nb material, the microstructure on the top surface layer is more disordered than that in-grain.

  8. Mapping of Proteomic Composition on the Surfaces of Bacillus spores by Atomic Force Microscopy-based Immunolabeling

    SciTech Connect

    Plomp, M; Malkin, A J

    2008-06-02

    Atomic force microscopy provides a unique capability to image high-resolution architecture and structural dynamics of pathogens (e.g. viruses, bacteria and bacterial spores) at near molecular resolution in native conditions. Further development of atomic force microscopy in order to enable the correlation of pathogen protein surface structures with specific gene products is essential to understand the mechanisms of the pathogen life cycle. We have applied an AFM-based immunolabeling technique for the proteomic mapping of macromolecular structures through the visualization of the binding of antibodies, conjugated with nanogold particles, to specific epitopes on Bacillus spore surfaces. This information is generated while simultaneously acquiring the surface morphology of the pathogen. The immunospecificity of this labeling method was established through the utilization of specific polyclonal and monoclonal antibodies that target spore coat and exosporium epitopes of Bacillus atrophaeus and Bacillus anthracis spores.

  9. Multivariate tensor-based morphometry on surfaces: application to mapping ventricular abnormalities in HIV/AIDS.

    PubMed

    Wang, Yalin; Zhang, Jie; Gutman, Boris; Chan, Tony F; Becker, James T; Aizenstein, Howard J; Lopez, Oscar L; Tamburo, Robert J; Toga, Arthur W; Thompson, Paul M

    2010-02-01

    Here we developed a new method, called multivariate tensor-based surface morphometry (TBM), and applied it to study lateral ventricular surface differences associated with HIV/AIDS. Using concepts from differential geometry and the theory of differential forms, we created mathematical structures known as holomorphic one-forms, to obtain an efficient and accurate conformal parameterization of the lateral ventricular surfaces in the brain. The new meshing approach also provides a natural way to register anatomical surfaces across subjects, and improves on prior methods as it handles surfaces that branch and join at complex 3D junctions. To analyze anatomical differences, we computed new statistics from the Riemannian surface metrics-these retain multivariate information on local surface geometry. We applied this framework to analyze lateral ventricular surface morphometry in 3D MRI data from 11 subjects with HIV/AIDS and 8 healthy controls. Our method detected a 3D profile of surface abnormalities even in this small sample. Multivariate statistics on the local tensors gave better effect sizes for detecting group differences, relative to other TBM-based methods including analysis of the Jacobian determinant, the largest and smallest eigenvalues of the surface metric, and the pair of eigenvalues of the Jacobian matrix. The resulting analysis pipeline may improve the power of surface-based morphometry studies of the brain.

  10. Multivariate tensor-based morphometry on surfaces: application to mapping ventricular abnormalities in HIV/AIDS.

    PubMed

    Wang, Yalin; Zhang, Jie; Gutman, Boris; Chan, Tony F; Becker, James T; Aizenstein, Howard J; Lopez, Oscar L; Tamburo, Robert J; Toga, Arthur W; Thompson, Paul M

    2010-02-01

    Here we developed a new method, called multivariate tensor-based surface morphometry (TBM), and applied it to study lateral ventricular surface differences associated with HIV/AIDS. Using concepts from differential geometry and the theory of differential forms, we created mathematical structures known as holomorphic one-forms, to obtain an efficient and accurate conformal parameterization of the lateral ventricular surfaces in the brain. The new meshing approach also provides a natural way to register anatomical surfaces across subjects, and improves on prior methods as it handles surfaces that branch and join at complex 3D junctions. To analyze anatomical differences, we computed new statistics from the Riemannian surface metrics-these retain multivariate information on local surface geometry. We applied this framework to analyze lateral ventricular surface morphometry in 3D MRI data from 11 subjects with HIV/AIDS and 8 healthy controls. Our method detected a 3D profile of surface abnormalities even in this small sample. Multivariate statistics on the local tensors gave better effect sizes for detecting group differences, relative to other TBM-based methods including analysis of the Jacobian determinant, the largest and smallest eigenvalues of the surface metric, and the pair of eigenvalues of the Jacobian matrix. The resulting analysis pipeline may improve the power of surface-based morphometry studies of the brain. PMID:19900560

  11. Potential of EnMAP spaceborne imaging spectroscopy for the prediction of common surface soil properties and expected accuracy

    NASA Astrophysics Data System (ADS)

    Chabrillat, Sabine; Foerster, Saskia; Steinberg, Andreas; Stevens, Antoine; Segl, Karl

    2016-04-01

    There is a renewed awareness of the finite nature of the world's soil resources, growing concern about soil security, and significant uncertainties about the carrying capacity of the planet. As a consequence, soil scientists are being challenged to provide regular assessments of soil conditions from local through to global scales. However, only a few countries have the necessary survey and monitoring programs to meet these new needs and existing global data sets are out-of-date. A particular issue is the clear demand for a new area-wide regional to global coverage with accurate, up-to-date, and spatially referenced soil information as expressed by the modeling scientific community, farmers and land users, and policy and decision makers. Soil spectroscopy from remote sensing observations based on studies from the laboratory scale to the airborne scale has been shown to be a proven method for the quantitative prediction of key soil surface properties in local areas for exposed soils in appropriate surface conditions such as low vegetation cover and low water content. With the upcoming launch of the next generation of hyperspectral satellite sensors in the next 3 to 5 years (EnMAP, HISUI, PRISMA, SHALOM), a great potential for the global mapping and monitoring of soil properties is appearing. Nevertheless, the capabilities to extend the soil properties current spectral modeling from local to regional scales are still to be demonstrated using robust methods. In particular, three central questions are at the forefront of research nowadays: a) methodological developments toward improved algorithms and operational tools for the extraction of soil properties, b) up scaling from the laboratory into space domain, and c) demonstration of the potential of upcoming satellite systems and expected accuracy of soil maps. In this study, airborne imaging spectroscopy data from several test sites are used to simulate EnMAP satellite images at 30 m scale. Then, different soil

  12. Expert system designed to assist in the interpretation and evaluation of thoracic surface maps produced by high-resolution electrocardiography

    SciTech Connect

    Johnson, J.K.

    1988-01-01

    An expert system is an artificial intelligence program that relies on a knowledge base composed of information derived from an expert and is designed to perform a difficult task. The system is usually domain specific and provides an interactive consultation with the user in problem solving. High-resolution electrocardiography is a technique for acquiring information about the heart's electrical activity with the use of multilead electrodes. Thoracic surface maps are presented at precise intervals during the depolarization/repolarization stages of a heartbeat. Cardiologists have determined methods for relating the thoracic maps to the actual tissue condition of the heart giving a basis for diagnoses. This work shows the anatomy of the heart, techniques for measuring that activity, and in detail, the techniques used with High Resolution Electrocardiography. The field of artificial intelligence is explored with an emphasis on expert systems. An expert system developed to diagnose the HRE record is presented.

  13. Potentiometric-surface map of water in the Judith River Formation in the Northern Great Plains area of Montana

    USGS Publications Warehouse

    Levings, Gary W.

    1982-01-01

    The potentiometric surface of the Judith River Formation is mapped at a scale of 1:1,000,000. The map is one of a series produced as part of a regional study of aquifers of Cenozoic and Mesozoic age in the northern Great Plains of Montana. The contour interval is 200 feet. Water in the Judith River Formation occurs under water-table and artesian conditions. The direction of regional ground-water movement is from west to east. Water is discharged from the Judith River Formation to the Milk River from near Havre, Montana, to Malta and to the Missouri River south of the Bearpaw and Little Rocky Mountains. The average discharge from 236 wells is about 10 gallons per minute, and the specific capacity of 186 wells averages 0.66 gallon per minute per foot of drawdown. (USGS)

  14. Statistical mapping of zones of focused groundwater/surface-water exchange using fiber-optic distributed temperature sensing

    USGS Publications Warehouse

    Mwakanyamale, Kisa; Day-Lewis, Frederick D.; Slater, Lee D.

    2013-01-01

    Fiber-optic distributed temperature sensing (FO-DTS) increasingly is used to map zones of focused groundwater/surface-water exchange (GWSWE). Previous studies of GWSWE using FO-DTS involved identification of zones of focused GWSWE based on arbitrary cutoffs of FO-DTS time-series statistics (e.g., variance, cross-correlation between temperature and stage, or spectral power). New approaches are needed to extract more quantitative information from large, complex FO-DTS data sets while concurrently providing an assessment of uncertainty associated with mapping zones of focused GSWSE. Toward this end, we present a strategy combining discriminant analysis (DA) and spectral analysis (SA). We demonstrate the approach using field experimental data from a reach of the Columbia River adjacent to the Hanford 300 Area site. Results of the combined SA/DA approach are shown to be superior to previous results from qualitative interpretation of FO-DTS spectra alone.

  15. Mapping paddy rice planting areas through time series analysis of MODIS land surface temperature and vegetation index data

    NASA Astrophysics Data System (ADS)

    Zhang, Geli; Xiao, Xiangming; Dong, Jinwei; Kou, Weili; Jin, Cui; Qin, Yuanwei; Zhou, Yuting; Wang, Jie; Menarguez, Michael Angelo; Biradar, Chandrashekhar

    2015-08-01

    Knowledge of the area and spatial distribution of paddy rice is important for assessment of food security, management of water resources, and estimation of greenhouse gas (methane) emissions. Paddy rice agriculture has expanded rapidly in northeastern China in the last decade, but there are no updated maps of paddy rice fields in the region. Existing algorithms for identifying paddy rice fields are based on the unique physical features of paddy rice during the flooding and transplanting phases and use vegetation indices that are sensitive to the dynamics of the canopy and surface water content. However, the flooding phenomena in high latitude area could also be from spring snowmelt flooding. We used land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor to determine the temporal window of flooding and rice transplantation over a year to improve the existing phenology-based approach. Other land cover types (e.g., evergreen vegetation, permanent water bodies, and sparse vegetation) with potential influences on paddy rice identification were removed (masked out) due to their different temporal profiles. The accuracy assessment using high-resolution images showed that the resultant MODIS-derived paddy rice map of northeastern China in 2010 had a high accuracy (producer and user accuracies of 92% and 96%, respectively). The MODIS-based map also had a comparable accuracy to the 2010 Landsat-based National Land Cover Dataset (NLCD) of China in terms of both area and spatial pattern. This study demonstrated that our improved algorithm by using both thermal and optical MODIS data, provides a robust, simple and automated approach to identify and map paddy rice fields in temperate and cold temperate zones, the northern frontier of rice planting.

  16. Mapping paddy rice planting areas through time series analysis of MODIS land surface temperature and vegetation index data

    PubMed Central

    Zhang, Geli; Xiao, Xiangming; Dong, Jinwei; Kou, Weili; Jin, Cui; Qin, Yuanwei; Zhou, Yuting; Wang, Jie; Menarguez, Michael Angelo; Biradar, Chandrashekhar

    2016-01-01

    Knowledge of the area and spatial distribution of paddy rice is important for assessment of food security, management of water resources, and estimation of greenhouse gas (methane) emissions. Paddy rice agriculture has expanded rapidly in northeastern China in the last decade, but there are no updated maps of paddy rice fields in the region. Existing algorithms for identifying paddy rice fields are based on the unique physical features of paddy rice during the flooding and transplanting phases and use vegetation indices that are sensitive to the dynamics of the canopy and surface water content. However, the flooding phenomena in high latitude area could also be from spring snowmelt flooding. We used land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor to determine the temporal window of flooding and rice transplantation over a year to improve the existing phenology-based approach. Other land cover types (e.g., evergreen vegetation, permanent water bodies, and sparse vegetation) with potential influences on paddy rice identification were removed (masked out) due to their different temporal profiles. The accuracy assessment using high-resolution images showed that the resultant MODIS-derived paddy rice map of northeastern China in 2010 had a high accuracy (producer and user accuracies of 92% and 96%, respectively). The MODIS-based map also had a comparable accuracy to the 2010 Landsat-based National Land Cover Dataset (NLCD) of China in terms of both area and spatial pattern. This study demonstrated that our improved algorithm by using both thermal and optical MODIS data, provides a robust, simple and automated approach to identify and map paddy rice fields in temperate and cold temperate zones, the northern frontier of rice planting. PMID:27667901

  17. Mapping paddy rice planting areas through time series analysis of MODIS land surface temperature and vegetation index data

    PubMed Central

    Zhang, Geli; Xiao, Xiangming; Dong, Jinwei; Kou, Weili; Jin, Cui; Qin, Yuanwei; Zhou, Yuting; Wang, Jie; Menarguez, Michael Angelo; Biradar, Chandrashekhar

    2016-01-01

    Knowledge of the area and spatial distribution of paddy rice is important for assessment of food security, management of water resources, and estimation of greenhouse gas (methane) emissions. Paddy rice agriculture has expanded rapidly in northeastern China in the last decade, but there are no updated maps of paddy rice fields in the region. Existing algorithms for identifying paddy rice fields are based on the unique physical features of paddy rice during the flooding and transplanting phases and use vegetation indices that are sensitive to the dynamics of the canopy and surface water content. However, the flooding phenomena in high latitude area could also be from spring snowmelt flooding. We used land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor to determine the temporal window of flooding and rice transplantation over a year to improve the existing phenology-based approach. Other land cover types (e.g., evergreen vegetation, permanent water bodies, and sparse vegetation) with potential influences on paddy rice identification were removed (masked out) due to their different temporal profiles. The accuracy assessment using high-resolution images showed that the resultant MODIS-derived paddy rice map of northeastern China in 2010 had a high accuracy (producer and user accuracies of 92% and 96%, respectively). The MODIS-based map also had a comparable accuracy to the 2010 Landsat-based National Land Cover Dataset (NLCD) of China in terms of both area and spatial pattern. This study demonstrated that our improved algorithm by using both thermal and optical MODIS data, provides a robust, simple and automated approach to identify and map paddy rice fields in temperate and cold temperate zones, the northern frontier of rice planting.

  18. Near-Surface Geophysical Mapping of the Hydrological Response to an Intense Rainfall Event at the Field Scale

    NASA Astrophysics Data System (ADS)

    Martínez, G.; Vanderlinden, K.; Giraldez, J. V.; Espejo, A. J.; Muriel, J. L.

    2009-12-01

    Soil moisture plays an important role in a wide variety of biogeochemical fluxes in the soil-plant-atmosphere system and governs the (eco)hydrological response of a catchment to an external forcing such as rainfall. Near-surface electromagnetic induction (EMI) sensors that measure the soil apparent electrical conductivity (ECa) provide a fast and non-invasive means for characterizing this response at the field or catchment scale through high-resolution time-lapse mapping. Here we show how ECa maps, obtained before and after an intense rainfall event of 125 mm h-1, elucidate differences in soil moisture patterns and hydrologic response of an experimental field as a consequence of differed soil management. The dryland field (Vertisol) was located in SW Spain and cropped with a typical wheat-sunflower-legume rotation. Both, near-surface and subsurface ECa (ECas and ECad, respectively), were measured using the EM38-DD EMI sensor in a mobile configuration. Raw ECa measurements and Mean Relative Differences (MRD) provided information on soil moisture patterns while time-lapse maps were used to evaluate the hydrologic response of the field. ECa maps of the field, measured before and after the rainfall event showed similar patterns. The field depressions where most of water and sediments accumulated had the highest ECa and MRD values. The SE-oriented soil, which was deeper and more exposed to sun and wind, showed the lowest ECa and MRD. The largest differences raised in the central part of the field where a high ECa and MRD area appeared after the rainfall event as a consequence of the smaller soil depth and a possible subsurface flux concentration. Time-lapse maps of both ECa and MRD were also similar. The direct drill plots showed higher increments of ECa and MRD as a result of the smaller runoff production. Time-lapse ECa increments showed a bimodal distribution differentiating clearly the direct drill from the conventional and minimum tillage plots. However this kind

  19. Estimation of land surface evaporation map over large areas using remote sensing data

    NASA Astrophysics Data System (ADS)

    Jiang, Le

    Accurate estimation of surface energy fluxes is essential for various hydrological, meteorological, agricultural and ecological applications. Over the years, a wide variety of instrument systems and estimation methodologies have been developed to measure and estimate surface fluxes. In this study, a simple scheme is proposed to estimate surface evaporation over large heterogeneous areas using remote sensing data. This approach is based on an extension of the Priestley-Taylor equation and a relationship between remotely sensed surface temperature and vegetation index. Further simplification by using more generalized form for remotely sensed surface parameters set leads to a simpler formulation for evaporative fraction within a trapezoid/triangle space of remotely sensed vegetation index and surface temperature parameter space. Compared to ground flux observations by the Atmospheric Radiation Measurement (ARM) program, six case studies varying from early spring to late summer over the central United States show that the proposed method provides better estimation accuracy for surface evaporation than the original Priestley-Taylor method. Detailed comparison with the widely used aerodynamic resistance energy balance residual method suggests that the proposed method can achieve similar or better estimation of latent heat flux over large areas with much less input parameters. The residual method, on the other hand, requires estimation of aerodynamic resistance to heat transfer that necessitates the measurements of several ground-based observations including land surface vegetation height and surface wind.

  20. Scanning Electron Microscope Mapping System Developed for Detecting Surface Defects in Fatigue Specimens

    NASA Technical Reports Server (NTRS)

    Bonacuse, Peter J.; Kantzos, Peter T.

    2002-01-01

    An automated two-degree-of-freedom specimen positioning stage has been developed at the NASA Glenn Research Center to map and monitor defects in fatigue specimens. This system expedites the examination of the entire gauge section of fatigue specimens so that defects can be found using scanning electron microscopy (SEM). Translation and rotation stages are driven by microprocessor-based controllers that are, in turn, interfaced to a computer running custom-designed software. This system is currently being used to find and record the location of ceramic inclusions in powder metallurgy materials. The mapped inclusions are periodically examined during interrupted fatigue experiments. The number of cycles to initiate cracks from these inclusions and the rate of growth of initiated cracks can then be quantified. This information is necessary to quantify the effect of this type of defect on the durability of powder metallurgy materials. This system was developed with support of the Ultra Safe program.

  1. C-band RISAT-1 imagery for geospatial mapping of cryospheric surface features in the Antarctic environment

    NASA Astrophysics Data System (ADS)

    Jawak, Shridhar D.; Panditrao, Satej N.; Luis, Alvarinho J.

    2016-05-01

    Cryospheric surface feature classification is one of the widely used applications in the field of polar remote sensing. Precise surface feature maps derived from remotely sensed imageries are the major requirement for many geoscientific applications in polar regions. The present study explores the capabilities of C-band dual polarimetric (HH & HV) SAR imagery from Indian Radar Imaging Satellite (RISAT-1) for land cryospheric surface feature mapping. The study areas selected for the present task were Larsemann Hills and Schirmacher Oasis, East Antarctica. RISAT-1 Fine Resolution STRIPMAP (FRS-1) mode data with 3-m spatial resolution was used in the present research attempt. In order to provide additional context to the amount of information in dual polarized RISAT-1 SAR data, a band HH+HV was introduced to make use of the original two polarizations. In addition to the data calibration, transformed divergence (TD) procedure was performed for class separability analysis to evaluate the quality of the statistics before image classification. For most of the class pairs the TD values were comparable, which indicated that the classes have good separability. Fuzzy and Artificial Neural Network classifiers were implemented and accuracy was checked. Nonparametric classifier Support Vector Machine (SVM) was also used to classify RISAT-1 data with an optimized polarization combination into three land-cover classes consisting of sea ice/snow/ice, rocks/landmass, and lakes/waterbodies. This study demonstrates that C-band FRS1 image mode data from the RISAT-1 mission can be exploited to identify, map and monitor land cover features in the polar regions, even during dark winter period. For better landcover classification and analysis, hybrid polarimetric data (cFRS-1 mode) from RISAT-1, which incorporates phase information, unlike the dual-pol linear (HH, HV) can be used for obtaining better polarization signatures.

  2. Including Faults Detected By Near-Surface Seismic Methods in the USGS National Seismic Hazard Maps - Some Restrictions Apply

    NASA Astrophysics Data System (ADS)

    Williams, R. A.; Haller, K. M.

    2014-12-01

    Every 6 years, the USGS updates the National Seismic Hazard Maps (new version released July 2014) that are intended to help society reduce risk from earthquakes. These maps affect hundreds of billions of dollars in construction costs each year as they are used to develop seismic-design criteria of buildings, bridges, highways, railroads, and provide data for risk assessment that help determine insurance rates. Seismic source characterization, an essential component of hazard model development, ranges from detailed trench excavations across faults at the ground surface to less detailed analysis of broad regions defined mainly on the basis of historical seismicity. Though it is a priority for the USGS to discover new Quaternary fault sources, the discovered faults only become a part of the hazard model if there are corresponding constraints on their geometry (length and depth extent) and slip-rate (or recurrence interval). When combined with fault geometry and slip-rate constraints, near-surface seismic studies that detect young (Quaternary) faults have become important parts of the hazard source model. Examples of seismic imaging studies with significant hazard impact include the Southern Whidbey Island fault, Washington; Santa Monica fault, San Andreas fault, and Palos Verdes fault zone, California; and Commerce fault, Missouri. There are many more faults in the hazard model in the western U.S. than in the expansive region east of the Rocky Mountains due to the higher rate of tectonic deformation, frequent surface-rupturing earthquakes and, in some cases, lower erosion rates. However, the recent increase in earthquakes in the central U.S. has revealed previously unknown faults for which we need additional constraints before we can include them in the seismic hazard maps. Some of these new faults may be opportunities for seismic imaging studies to provide basic data on location, dip, style of faulting, and recurrence.

  3. Simultaneous Mapping of Titan's Atmospheric and Surface Properties Through the Massive Inversion of Cassini/VIMS Data

    NASA Astrophysics Data System (ADS)

    Rodriguez, S.; Maltagliati, L.; Appéré, T.; Vincendon, M.; Douté, S.; Le Mouelic, S.; Rannou, P.; Sotin, C.; Barnes, J. W.; Coustenis, A.; Brown, R. H.

    2014-12-01

    A radiative transfer solver (i.e. SHDOM) is the most powerful tool to extract simultaneous information of the atmosphere and the surface of Titan from the hyperspectral data of the VIMS imaging spectrometer onboard Cassini. However, the sheer amount of data (~40000 VIMS cubes containing several millions of spectra since the beginning of the mission) makes this approach too demanding in computational time. In our analysis we use a radiative transfer model to create look-up tables for different values of the model's parameters (geometry of the observation, surface albedo, aerosols opacity). We employ up-to-date information on gaseous spectral coefficients, aerosols' optical properties and Titan's climatology. These look-up tables, appropriately interpolated, are then used to minimize the observations and create simultaneous maps of surface albedo at the wavelengths of Titan's spectral windows and of aerosols opacity. This approach allows the gain of a factor of several thousands in computational time and thus, for the first time, a truly massive treatment of VIMS data. This capacity of processing full mapping quickly will consent to monitor closely the global and local seasonal evolution of the atmosphere and the surface. We will present the results of our method applied to some cases of interest. We will analyze several hyperspectral images of the Huygens landing site and show the comparison of our results with observations of other Cassini instruments. We will also investigate regions that have been observed multiple times at different Cassini flybys with different observational conditions, as the T13/T17 mosaic of the Atzlan area. The perspectives for atmospheric and surface seasonal monitoring will be highlighted.

  4. Comet 67P/C-G: Surface Temperatures as Derived by Rosetta/VIRTIS in the Mapping Phase

    NASA Astrophysics Data System (ADS)

    Tosi, F.; Capria, M. T.; Capaccioni, F.; Filacchione, G.; De Sanctis, M. C.; Erard, S.; Leyrat, C.; Bockelée-Morvan, D.; Kuhrt, E.

    2014-12-01

    We show spatially-resolved temperature maps of comet 67P/Churyumov-Gerasimenko, main target of the ESA Rosetta spacecraft, as derived from infrared hyperspectral images acquired by the VIRTIS imaging spectrometer onboard the Rosetta Orbiter in the Mapping phase carried out in August and September 2014. These data were obtained during the Mapping phase, at variable spatial resolution (from roughly 100 m/px down to ~10 m/px), illumination conditions, and heliocentric distances (spanning the range from 3.6 to 3.4 AU). VIRTIS infrared spectra in the range longward of ~4 μm are affected by the thermal emission of the comet, hence the measured radiance in that spectral region can be used to determine surface temperatures and spectral emissivities by means of temperature-retrieval algorithms. We use a Bayesian approach that was previously applied to Rosetta/VIRTIS data obtained during the close flybys of asteroids 2678 Steins and 21 Lutetia, as well as to the entire dataset of infrared data acquired by the VIR mapping spectrometer aboard the Dawn spacecraft during its orbital phase at asteroid Vesta in 2011-2012. The VIRTIS instrument onboard Rosetta is not sensitive to physical temperatures on the nightside of the comet, where the signal is considerably low. Typically, ~170 K is the minimum temperature that allows one to retrieve surface temperatures while preserving high accuracies. On the other hand, for a given local solar time, the maximum temperature depends on the solar incidence angle and on surface properties such as thermal inertia and albedo. The availability of spatially-resolved, accurate temperature observations, significantly spaced out in local solar time, provides clues to the physical structure of specific surface units, which complements the mineralogical investigation based on imaging spectroscopy data collected at shorter wavelengths. AcknowledgementsThis work is supported by the Italian Space Agency (ASI), ASI-INAF Contract n. I/024/12/0. We

  5. AN ACCURACY ASSESSMENT OF MULTIPLE MID-ATLANTIC SUB-PIXEL IMPERVIOUS SURFACE MAPS

    EPA Science Inventory

    Anthropogenic impervious surfaces have an important relationship with non-point source pollution (NPS) in urban watersheds. The amount of impervious surface area in a watershed is a key indicator of landscape change. As a single variable, it serves to integrate a number of conc...

  6. Mapping surface tension induced menisci with application to tensiometry and refractometry.

    PubMed

    Mishra, Avanish; Kulkarni, Varun; Khor, Jian-Wei; Wereley, Steve

    2015-07-28

    In this work, we discuss an optical method for measuring surface tension induced menisci. The principle of measurement is based upon the change in the background pattern produced by the curvature of the meniscus acting as a lens. We measure the meniscus profile over an inclined glass plate and utilize the measured meniscus for estimation of surface tension and refractive index. PMID:26106879

  7. Local shape similarity and mean-shift curvature for deformable surface mapping of anatomical structures.

    PubMed

    Cerveri, Pietro; Manzotti, Alfonso; Vanzulli, Angelo; Baroni, Guido

    2014-01-01

    This paper reports a novel method for deformable registration of digital anatomical surfaces. The method capitalizes upon the iterative local affine iterative closest point (ICP) approach that applies an affine transformation per surface vertex along with a regularization constraint to force neighboring surface vertices to undergo similar transformations. More robust vertex correspondence with respect to simple closest point was obtained by exploiting local shape similarity metrics, which includes vertex distance, surface normal, and local curvature. The local curvature was mean shifted at run-time, during the iterative optimization, to make the point correspondence process less dependent upon the surface noise and resolution. The experimental validation was performed on three surface datasets (femur, hemi-pelvic bone, and liver). The registration results showed that the proposed method outperforms, across all the three surface datasets (rmse: 0.19 mm, 0.30 mm, 0.61 mm), global affine ICP (rmse: 2.89 mm, 3.95 mm, and 8.30 mm), local affine ICP (rmse: 0.31 mm, 1.61 mm, and 1.63 mm) and coherent point drift (rmse: 1.99 mm, 2.39 mm, and 4.78 mm) methods. As a whole, the mean-shifted curvature increased the registration accuracy by about 20%. PMID:23912461

  8. Three-dimensional hydration layer mapping on the (10.4) surface of calcite using amplitude modulation atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Marutschke, Christoph; Walters, Deron; Cleveland, Jason; Hermes, Ilka; Bechstein, Ralf; Kühnle, Angelika

    2014-08-01

    Calcite, the most stable modification of calcium carbonate, is a major mineral in nature. It is, therefore, highly relevant in a broad range of fields such as biomineralization, sea water desalination and oil production. Knowledge of the surface structure and reactivity of the most stable cleavage plane, calcite (10.4), is pivotal for understanding the role of calcite in these diverse areas. Given the fact that most biological processes and technical applications take place in an aqueous environment, perhaps the most basic—yet decisive—question addresses the interaction of water molecules with the calcite (10.4) surface. In this work, amplitude modulation atomic force microscopy is used for three-dimensional (3D) mapping of the surface structure and the hydration layers above the surface. An easy-to-use scanning protocol is implemented for collecting reliable 3D data. We carefully discuss a comprehensible criterion for identifying the solid-liquid interface within our data. In our data three hydration layers form a characteristic pattern that is commensurate with the underlying calcite surface.

  9. Three-dimensional hydration layer mapping on the (10.4) surface of calcite using amplitude modulation atomic force microscopy.

    PubMed

    Marutschke, Christoph; Walters, Deron; Walters, Deron; Hermes, Ilka; Bechstein, Ralf; Kühnle, Angelika

    2014-08-22

    Calcite, the most stable modification of calcium carbonate, is a major mineral in nature. It is, therefore, highly relevant in a broad range of fields such as biomineralization, sea water desalination and oil production. Knowledge of the surface structure and reactivity of the most stable cleavage plane, calcite (10.4), is pivotal for understanding the role of calcite in these diverse areas. Given the fact that most biological processes and technical applications take place in an aqueous environment, perhaps the most basic - yet decisive - question addresses the interaction of water molecules with the calcite (10.4) surface. In this work, amplitude modulation atomic force microscopy is used for three-dimensional (3D) mapping of the surface structure and the hydration layers above the surface. An easy-to-use scanning protocol is implemented for collecting reliable 3D data. We carefully discuss a comprehensible criterion for identifying the solid-liquid interface within our data. In our data three hydration layers form a characteristic pattern that is commensurate with the underlying calcite surface. PMID:25074402

  10. Three-dimensional hydration layer mapping on the (10.4) surface of calcite using amplitude modulation atomic force microscopy.

    PubMed

    Marutschke, Christoph; Walters, Deron; Walters, Deron; Hermes, Ilka; Bechstein, Ralf; Kühnle, Angelika

    2014-08-22

    Calcite, the most stable modification of calcium carbonate, is a major mineral in nature. It is, therefore, highly relevant in a broad range of fields such as biomineralization, sea water desalination and oil production. Knowledge of the surface structure and reactivity of the most stable cleavage plane, calcite (10.4), is pivotal for understanding the role of calcite in these diverse areas. Given the fact that most biological processes and technical applications take place in an aqueous environment, perhaps the most basic - yet decisive - question addresses the interaction of water molecules with the calcite (10.4) surface. In this work, amplitude modulation atomic force microscopy is used for three-dimensional (3D) mapping of the surface structure and the hydration layers above the surface. An easy-to-use scanning protocol is implemented for collecting reliable 3D data. We carefully discuss a comprehensible criterion for identifying the solid-liquid interface within our data. In our data three hydration layers form a characteristic pattern that is commensurate with the underlying calcite surface.

  11. Mapping the near-field propagation of surface plasmons on terahertz metasurfaces

    SciTech Connect

    Xu, Yuehong; Zhang, Xueqian; Tian, Zhen; Gu, Jianqiang; Ouyang, Chunmei; Li, Yanfeng; Han, Jiaguang; Zhang, Weili

    2015-07-13

    Controlling the propagation of surface plasmon polaritons is essential in developing highly integrated photonic devices. By using near-field scanning terahertz microscopy, we experimentally demonstrate that polarization-controlled tunable surface plasmons (SPs) could be directionally excited on a metal surface with carved columns of aperture resonators under special arrangement. The experimental results reveal that terahertz SPs could be unidirectionally launched in opposite directions owning to destructive and constructive interferences on the two sides with circularly polarized incident waves of opposite handedness. Meanwhile, the linearly polarized wave is able to excite the terahertz SPs along either side of the structures. The presented results would be useful to implement functional terahertz plasmonic devices.

  12. Sensitivity of thermal inertia calculations to variations in environmental factors. [in mapping of Earth's surface by remote sensing

    NASA Technical Reports Server (NTRS)

    Kahle, A. B.; Alley, R. E.; Schieldge, J. P.

    1984-01-01

    The sensitivity of thermal inertia (TI) calculations to errors in the measurement or parameterization of a number of environmental factors is considered here. The factors include effects of radiative transfer in the atmosphere, surface albedo and emissivity, variations in surface turbulent heat flux density, cloud cover, vegetative cover, and topography. The error analysis is based upon data from the Heat Capacity Mapping Mission (HCMM) satellite for July 1978 at three separate test sites in the deserts of the western United States. Results show that typical errors in atmospheric radiative transfer, cloud cover, and vegetative cover can individually cause root-mean-square (RMS) errors of about 10 percent (with atmospheric effects sometimes as large as 30-40 percent) in HCMM-derived thermal inertia images of 20,000-200,000 pixels.

  13. Scattering of electromagnetic waves from surfaces with conformal mapping: An example of a triangular plate.

    PubMed

    Chui, S T; Wang, Shubo; Chan, C T

    2016-03-01

    We discuss a way to exploit conformal mapping to study the response of a finite metallic film of arbitrary shape to an external electromagnetic field at finite frequencies. This provides a simple way to understand different physics issues and provides insights that include the issue of vorticity and eddy current and the nature of the divergent electric field at the boundaries and at corners. We study an example of an equilateral triangular plate and find good agreement with results obtained with traditional numerical techniques.

  14. The control network of Rhea. [surface feature coordinates for satellite mapping

    NASA Technical Reports Server (NTRS)

    Davies, M. E.; Katayama, F. Y.

    1983-01-01

    A control network of the Saturnian satellite Rhea has been established photogrammetrically from pictures taken by the two Voyager spacecraft. Coordinates of 288 control points on Rhea have been computed and listed; some of these are identified on the preliminary U.S. Geological Survey map of Rhea and many of the control point features have been named. Pixel measurements of these points were made on 81 Voyager 1 and 3 Voyager 2 pictures. The longitude system on Rhea is defined by the crater Tore; the 340 deg meridian passes through the center of this crater. The mean radius of Rhea has been determined at 764 + or - 4 km.

  15. Acid-base site detection and mapping on solid surfaces by Kelvin force microscopy (KFM).

    PubMed

    Gouveia, Rubia F; Bernardes, Juliana S; Ducati, Telma R D; Galembeck, Fernando

    2012-12-01

    Electrostatic potential at the surface of acidic or basic solids changes under higher relative humidity (RH), as determined by using Kelvin force microscopy (KFM). The potential on acid surfaces becomes more negative as the water vapor pressure increases, while it becomes more positive on basic solids. These results verify the following hypothesis: OH(-) or H(+) ions associated with atmospheric water ion clusters are selectively adsorbed on solid surfaces, depending on the respective Brønsted acid or base character. Therefore, Kelvin microscopy, under variable humidity, is a rigorous but convenient alternative to determine the acid-base character of solid surfaces, with a great advantage: it uses only one amphoteric and simple reagent to determine both the acid and base sites. Moreover, this technique provides information on the spatial distribution of acid-base sites, which is currently inaccessible to any other method.

  16. Advances in Shallow-Water, High-Resolution Seafloor Mapping: Integrating an Autonomous Surface Vessel (ASV) Into Nearshore Geophysical Studies

    NASA Astrophysics Data System (ADS)

    Denny, J. F.; O'Brien, T. F.; Bergeron, E.; Twichell, D.; Worley, C. R.; Danforth, W. W.; Andrews, B. A.; Irwin, B.

    2006-12-01

    The U.S. Geological Survey (USGS) has been heavily involved in geological mapping of the seafloor since the 1970s. Early mapping efforts such as GLORIA provided broad-scale imagery of deep waters (depths > 400 meters) within the Exclusive Economic Zone (EEZ). In the early 1990's, the USGS research emphasis shifted from deep- to shallow-water environments (inner continental shelf, nearshore, estuaries) to address pertinent coastal issues such as erosion, sediment availability, sediment transport, vulnerability of coastal areas to natural and anthropogenic hazards, and resource management. Geologic framework mapping in these shallow- water environments has provided valuable data used to 1) define modern sediment distribution and thickness, 2) determine underlying stratigraphic and structural controls on shoreline behavior, and 3) enable onshore-to- offshore geologic mapping within the coastal zone when coupled with subaerial techniques such as GPR and topographic LIDAR. Research in nearshore areas presents technological challenges due to the dynamics of the environment, high volume of data collected, and the geophysical limitations of operating in very shallow water. In 2004, the USGS, in collaboration with NOAA's Coastal Services Center, began a multi-year seafloor mapping effort to better define oyster habitats within Apalachicola Bay, Florida, a shallow water estuary along the northern Gulf of Mexico. The bay poses a technological challenge due to its shallow depths (< 4-m) and high turbidity that prohibits the use of bathymetric LIDAR. To address this extreme shallow water setting, the USGS incorporated an Autonomous Surface Vessel (ASV) into seafloor mapping operations, in June 2006. The ASV is configured with a chirp sub-bottom profiler (4 24 kHz), dual-frequency chirp sidescan-sonar (100/500 kHz), single-beam echosounder (235 kHz), and forward-looking digital camera, and will be used to delineate the distribution and thickness of surficial sediment, presence

  17. Mapping the Atmospheric and Surface Properties of Titan by the Massive Inversion of Cassini/VIMS Spectra

    NASA Astrophysics Data System (ADS)

    Maltagliati, Luca; Rodriguez, Sébastien; Appéré, Thomas; Vincendon, Mathieu; Douté, Sylvain; LeMouelic, Stéphane; Rannou, Pascal; Sotin, Christophe; Barnes, Jason W.; Coustenis, Athena; Brown, Robert H.

    2014-11-01

    Since the beginning of the Cassini mission, the imaging spectrometer VIMS has acquired ~40000 hyperspectral images of Titan containing several millions of spectra. Such a huge amount of data cannot be analyzed with a radiative transfer solver like SHDOM because of computational limits. Nevertheless, such a solver is the most suited tool to extract simultaneous information of the atmosphere and the surface of Titan from VIMS datacubes. We have developed a method of analyzing VIMS data that consents to use the power of a RT model without the inconvenience of long computational times, by the creation of look-up tables for different values of the RT model's parameters (geometry of the observation, surface albedo, aerosols opacity). We employ up-to-date information on gaseous spectral coefficients, aerosols’ optical properties and Titan’s climatology. These look-up tables, appropriately interpolated, are then used to minimize the observations and create simultaneous maps of aerosols opacity and of surface albedo (at the wavelengths of Titan’s spectral windows). This method lowers the computational time by a factor of several thousands and thus, for the first time, a truly massive treatment of VIMS data. In this paper we present the results of our method applied to the area of the Huygens landing site and their comparison with the results of other Cassini instruments. We also show the retrieved maps of a region observed multiple times at different Cassini flybys with different observational conditions, as the T13/T17 mosaic of the Atzlan area. The perspectives for atmospheric and surface seasonal monitoring are highlighted.

  18. Natural history of left ventricular size and function after acute myocardial infarction. Assessment and prediction by echocardiographic endocardial surface mapping.

    PubMed

    Picard, M H; Wilkins, G T; Ray, P A; Weyman, A E

    1990-08-01

    To investigate the natural history of regional dyssynergy and left ventricular size after myocardial infarction, 57 patients with a first Q wave myocardial infarction (18 anterior, 35 inferior, and four apical by echocardiography) were studied by two-dimensional echocardiography and compared with 30 control patients. Measurements from the echocardiograms were used to construct maps of the left ventricular endocardial surface from which the endocardial surface area index (ESAi) and the percent of the endocardial surface area involved by abnormal wall motion (%AWM) were calculated. The maps from entry and 3-month echocardiograms were used to classify patients based on changes in ESAi and abnormal wall motion. Two subgroups of patients were identified at entry--those with a normal ESAi (group 1, n = 50) and those with an increased ESAi (group 2, n = 7). Group 1 patients was subdivided at 3 months by changes occurring in ESAi (1A, 5% increase [n = 19]; 1B, no change [n = 23]; 1C, 5% decrease [n = 8]). The increase in ESAi (64.9 +/- 5.2 to 75.4 +/- 7.5 cm2/m2, p less than 0.0001) in group 1A was associated with global ventricular dilatation (n = 11) and clinically silent infarct extension (n = 8). Groups 1B and 1C were composed predominantly of patients with inferior infarctions, and all exhibited either no change or a significant decrease in infarct size (infarct regression). Group 2 patients demonstrated a continued increase in ESAi by 3 months (88.2 +/- 10.0 to 101.4 +/- 15.5 cm2/m2, p less than 0.007). This group comprised only patients with anterior infarctions, and all exhibited infarct expansion at the left ventricular apex. The changes in left ventricular size and functional infarct size are heterogeneous after acute myocardial infarction and relate to the initial endocardial surface area, infarct location, and functional infarct size. PMID:2372895

  19. Temporal and spatial mapping of surface albedo and atmospheric dust opacity on Mars

    NASA Technical Reports Server (NTRS)

    Lee, S. W.; Clancy, R. T.; Gladstone, G. R.

    1993-01-01

    The Mariner 9 and Viking provided abundant evidence that eolian processes are active over much of the surface of Mars. Past studies have demonstrated that variations in regional albedo and wind-streak patterns are indicative of sediment transport through a region, while thermal inertia data (derived from the Viking Infrared Thermal Mapper (IRTM) dataset) are indicative of the degree of surface mantling by dust deposits. The visual and thermal data are therefore diagnostic of whether net erosion or deposition of dust-storm fallout is taking place currently and whether such processes have been active in a region over the long term. These previous investigations, however, have not attempted to correct for the effects of atmospheric dust loading on observations of the martian surface, so quantitative studies of current sediment transport rates have included large errors due to uncertainty in the magnitude of this 'atmospheric component' of the observations. We have developed a radiative transfer model that allows the atmospheric dust opacity to be determined from IRTM thermal observations. Corrections for the effects of atmospheric dust loading on observations of surface albedo can also be modeled. This approach to determining 'dust-corrected surface albedo' incorporates the atmospheric dust opacity, the single-scattering albedo and particle phase function of atmospheric dust, and the bidirectional reflectance of the surface, and it accounts for variable lighting and viewing geometry.

  20. Surface mapping for visualization of wall stresses during inhalation in a human nasal cavity.

    PubMed

    Inthavong, Kiao; Shang, Yidan; Tu, Jiyuan

    2014-01-01

    Airflow analysis can assist in better understanding the physiology however the human nasal cavity is an extremely complicated geometry that is difficult to visualize in 3D space, let alone in 2D space. In this paper, an anatomically accurate 3D surface of the nasal passages derived from CT data was unwrapped and transformed into a 2D space, into a UV-domain (where u and v are the coordinates) to allow a complete view of the entire wrapped surface. This visualization technique allows surface flow parameters to be analyzed with greater precision. A UV-unwrapping tool is developed and a strategy is presented to allow deeper analysis to be performed. This includes (i) the ability to present instant comparisons of geometry and flow variables between any number of different nasal cavity models through normalization of the 2D unwrapped surface; (ii) visualization of an entire surface in one view and; (iii) a planar surface that allows direct 1D and 2D analytical solutions of diffusion of inhaled vapors and particles through the nasal walls. This work lays a foundation for future investigations that correlates adverse and therapeutic health responses to local inhalation of gases and particles.

  1. Mapping amorphous material on a partially crystalline surface: nanothermal analysis for simultaneous characterisation and imaging of lactose compacts.

    PubMed

    Dai, Xuan; Reading, Mike; Craig, Duncan Q M

    2009-04-01

    The use of nanothermal analysis for mapping amorphous and crystalline lactose at a nanoscale is explored. Compressed tablets of amorphous and crystalline lactose (alone and mixed) were prepared and localised thermomechanical analysis (L-TMA) performed using micro- and nanothermal analysis in a addition to single point variable temperature pull-off force measurements. L-TMA was shown to be able to identify the different materials at a nanoscale via measurement of the thermal events associated with the amorphous and crystalline regions, while pull off force measurements showed that the adhesion of the amorphous material increased on approaching the T(g). Imaging was performed isothermally using topographic and pulsed force mode (PFM) measurements; both approaches were capable of discriminating two regions which L-TMA conformed to correspond to the two materials. In addition, force volume imaging (FVI) is suggested as a further approach to mapping the surfaces. We demonstrate that performing heated tip PFM measurements at a temperature close to the T(g) allows greater discrimination between the two regions. We therefore suggest that the nanothermal approach allows both characterisation and imaging of partially amorphous surfaces, and also demonstrate that heated tip imaging allows greater discrimination between crystalline and amorphous materials than is possible using ambient studies. PMID:18752293

  2. Surface invasive cleavage assay on a maskless light-directed diamond DNA microarray for genome-wide human SNP mapping.

    PubMed

    Nie, Bei; Yang, Min; Fu, Weiling; Liang, Zhiqing

    2015-07-01

    The surface invasive cleavage assay, because of its innate accuracy and ability for self-signal amplification, provides a potential route for the mapping of hundreds of thousands of human SNP sites. However, its performance on a high density DNA array has not yet been established, due to the unusual "hairpin" probe design on the microarray and the lack of chemical stability of commercially available substrates. Here we present an applicable method to implement a nanocrystalline diamond thin film as an alternative substrate for fabricating an addressable DNA array using maskless light-directed photochemistry, producing the most chemically stable and biocompatible system for genetic analysis and enzymatic reactions. The surface invasive cleavage reaction, followed by degenerated primer ligation and post-rolling circle amplification is consecutively performed on the addressable diamond DNA array, accurately mapping SNP sites from PCR-amplified human genomic target DNA. Furthermore, a specially-designed DNA array containing dual probes in the same pixel is fabricated by following a reverse light-directed DNA synthesis protocol. This essentially enables us to decipher thousands of SNP alleles in a single-pot reaction by the simple addition of enzyme, target and reaction buffers.

  3. Calculating High Resolution CWSI Maps for Entire Growing Season of a Cultivated Barley Field with UAV-Collected Surface Temperatures.

    NASA Astrophysics Data System (ADS)

    Hoffmann, H.; Jensen, R.; Nieto Solana, H.; Friborg, T.; Thomsen, A.

    2015-12-01

    With agriculture as the largest consumer of freshwater and an overall increasing pressure on water resources, developing more efficient irrigation systems is important. Combining the crop water stress index (CWSI) with unmanned aerial vehicles (UAVs) enables detection of which specific areas within a cultivated field that requires irrigation to ensure healthy growing plants. In this study remotely sensed, high resolution surface temperatures are collected with a thermal camera onboard an UAV. Temperatures are used to calculate spatially distributed, high resolution CWSI maps over a barley field during growing seasons 2014 and 2015. In early stages of the barley growing season, surface temperatures are an ensemble of both soil and canopy temperatures. Canopy temperatures are extracted using leaf area index and the two source energy balance modelling scheme. This approach enables CWSI calculations for homogeneous and evenly distributed crops (such as barley) during early as well as late stages of a growing season. CWSI maps are calculated using both an empirical and an analytical approach and are compared and validated against modelled canopy conductance and transpiration rates.

  4. Improved mapping of information distribution across the cortical surface with the Support Vector Machine

    PubMed Central

    Xiao, Youping; Rao, Ravi; Cecchi, Guillermo; Kaplan, Ehud

    2008-01-01

    The early visual cortices represent information of several stimulus attributes, such as orientation and color. To understand the coding mechanisms of these attributes in the brain, and the functional organization of the early visual cortices, it is necessary to determine whether different attributes are represented by different compartments within each cortex. Previous studies addressing this question have focused on the information encoded by the response amplitude of individual neurons or cortical columns, and have reached conflicting conclusions. Given the correlated variability in response amplitude across neighboring columns, it is likely that the spatial pattern of responses across these columns encodes the attribute information more reliably than the response amplitude does. Here we present a new method of mapping the spatial distribution of information that is encoded by both the response amplitude and spatial pattern. This new method is based on a statistical learning approach, the Support Vector Machine (SVM). Application of this new method to our optical imaging data suggests that information about stimulus orientation and color are distributed differently in the striate cortex, and this observation is consistent with the hypothesis of segregated representations of orientation and color in this area. We also demonstrate that SVM can be used to extract ‘single-condition’ activation maps from noisy images of intrinsic optical signals. PMID:18249089

  5. Mapping of Synaptic-Neuronal Impairment on the Brain Surface through Fluctuation Analysis

    NASA Astrophysics Data System (ADS)

    Musha, Toshimitsu; Kurachi, Takayoshi; Suzuki, Naohoro; Kosugi, Yukio

    2005-08-01

    Increase of demented population year by year is becoming a serious social problem to be solved urgently. The most effective way to block this increase is in its early detection by means of an inexpensive, non-invasive, sensitive, reliable and easy-to-operate diagnosis method. We have developed a method satisfying these requirements by using scalp potential fluctuations. We have collected 21ch EEG and SPECT data of 25 very mild Alzheimer's disease (AD) (MMSE=26±1.8), moderately severe AD (MMSE=15.3±6.4) and age-matched normal controls. As AD progresses, local synaptic-neuronal activity becomes abnormal, either more unstable or more inactive than in normal state. Such abnormality is detected in terms of normalized power variance (NPV) of a scalp potential recorded with a scalp electrode. The z-score is defined by z = ((NPV of a subject) — (mean NPV of normal subjects))/(standard deviation of NPV of normal subjects). Correlation of a measured z-score map with the mean z-score map for AD patients characterizes likelihood to AD, in terms of which AD is discriminated from normal with 75% of true positive and 25% false negative probability. By introducing two thresholds, we have 90% of true positive and 10% of false negative discrimination.

  6. Mapping of Synaptic-Neuronal Impairment on the Brain Surface through Fluctuation Analysis

    SciTech Connect

    Musha, Toshimitsu; Kurachi, Takayoshi; Suzuki, Naohoro; Kosugi, Yukio

    2005-08-25

    Increase of demented population year by year is becoming a serious social problem to be solved urgently. The most effective way to block this increase is in its early detection by means of an inexpensive, non-invasive, sensitive, reliable and easy-to-operate diagnosis method. We have developed a method satisfying these requirements by using scalp potential fluctuations. We have collected 21ch EEG and SPECT data of 25 very mild Alzheimer's disease (AD) (MMSE=26{+-}1.8), moderately severe AD (MMSE=15.3{+-}6.4) and age-matched normal controls. As AD progresses, local synaptic-neuronal activity becomes abnormal, either more unstable or more inactive than in normal state. Such abnormality is detected in terms of normalized power variance (NPV) of a scalp potential recorded with a scalp electrode. The z-score is defined by z = ((NPV of a subject) - (mean NPV of normal subjects))/(standard deviation of NPV of normal subjects). Correlation of a measured z-score map with the mean z-score map for AD patients characterizes likelihood to AD, in terms of which AD is discriminated from normal with 75% of true positive and 25% false negative probability. By introducing two thresholds, we have 90% of true positive and 10% of false negative discrimination.

  7. Correlation between echocardiographic endocardial surface mapping of abnormal wall motion and pathologic infarct size in autopsied hearts.

    PubMed

    Wilkins, G T; Southern, J F; Choong, C Y; Thomas, J D; Fallon, J T; Guyer, D E; Weyman, A E

    1988-05-01

    We previously developed a cross-sectional echocardiographic technique for quantitatively mapping the endocardial surface of the left ventricle and on which regions of abnormal wall motion can be superimposed in their correct spatial distribution. This endocardial mapping technique (EMT) provides a measure of the left ventricular endocardial surface area (ESA in cm2), the area of abnormal wall motion (AWM in cm2), and the overall percent dysfunction (%AWM) as a measure of the functional "infarct size." To test this approach, we compared the EMT measurements with the actual endocardial surface area (in cm2) and pathologic infarct size (both percent infarct by volume and percent endocardial surface overlying infarct) measured at later autopsy in 20 adults (14 men, six women) ranging in age from 47 to 76 years (mean 64 +/- 9.6 years). The median interval from echocardiographic study to death was 19 days (range 1 to 269 days). Patients were divided into two groups based on the age of their infarcts at the time of death: (1) recent (infarct age less than 14 days; mean age 5.3 +/- 4.6 days) and (2) old (infarct age greater than 6 months; mean age 3.6 +/- 3 years). When the left ventricular endocardial surface area at autopsy was compared with the EMT-derived ESA, a close correlation was found (EMT area = 1.17 X autopsy area + 20.4; r = .94, p = .0001), with the systematic difference in the measurements accounted for by systolic arrest, loss of distending pressure, and specimen shrinkage. The echocardiographic measure of infarct size (%AWM) correlated well with the autopsy percent infarction by volume (%AWM = 1.1 X infarct volume + 5.5; r = .82, p = .0001). Similarly, a good correlation was found for the percent abnormal wall motion and the autopsy percent endocardial surface area overlying infarction (%AWM = 0.89 X infarct area - 0.9; r = .89, p = .0001). When the data were examined in relation to the age of the myocardial infarct, the echocardiographic %AWM appeared to

  8. Surface errors without semantic impairment in acquired dyslexia: a voxel-based lesion-symptom mapping study.

    PubMed

    Binder, Jeffrey R; Pillay, Sara B; Humphries, Colin J; Gross, William L; Graves, William W; Book, Diane S

    2016-05-01

    Patients with surface dyslexia have disproportionate difficulty pronouncing irregularly spelled words (e.g. pint), suggesting impaired use of lexical-semantic information to mediate phonological retrieval. Patients with this deficit also make characteristic 'regularization' errors, in which an irregularly spelled word is mispronounced by incorrect application of regular spelling-sound correspondences (e.g. reading plaid as 'played'), indicating over-reliance on sublexical grapheme-phoneme correspondences. We examined the neuroanatomical correlates of this specific error type in 45 patients with left hemisphere chronic stroke. Voxel-based lesion-symptom mapping showed a strong positive relationship between the rate of regularization errors and damage to the posterior half of the left middle temporal gyrus. Semantic deficits on tests of single-word comprehension were generally mild, and these deficits were not correlated with the rate of regularization errors. Furthermore, the deep occipital-temporal white matter locus associated with these mild semantic deficits was distinct from the lesion site associated with regularization errors. Thus, in contrast to patients with surface dyslexia and semantic impairment from anterior temporal lobe degeneration, surface errors in our patients were not related to a semantic deficit. We propose that these patients have an inability to link intact semantic representations with phonological representations. The data provide novel evidence for a post-semantic mechanism mediating the production of surface errors, and suggest that the posterior middle temporal gyrus may compute an intermediate representation linking semantics with phonology. PMID:26966139

  9. Dust transport over the eastern Mediterranean derived from Total Ozone Mapping Spectrometer, Aerosol Robotic Network, and surface measurements

    NASA Astrophysics Data System (ADS)

    Kalivitis, N.; Gerasopoulos, E.; Vrekoussis, M.; Kouvarakis, G.; Kubilay, N.; Hatzianastassiou, N.; Vardavas, I.; Mihalopoulos, N.

    2007-02-01

    Multiyear surface PM10 measurements performed on Crete Island, Greece, have been used in conjunction with satellite (Total Ozone Mapping Spectrometer (TOMS)) and ground-based remote sensing measurements (Aerosol Robotic Network (AERONET)) to enhance our understanding of the evolution of mineral dust events over the eastern Mediterranean. An analysis of southerly air masses at altitudes of 1000 and 3000 m over a 5 year period (2000-2005), showed that dust can potentially arrive over Crete, either simultaneously in the lower free troposphere and inside the boundary layer (vertical extended transport (VET)) or initially into the free troposphere with the heavier particles gradually being scavenged inside the boundary layer (free troposphere transport (FTT)). Both pathways present significant seasonal variations but on an annual basis contribute almost equally to the dust transport in the area. During VET the aerosol index (AI) derived from TOMS was significantly correlated with surface PM10, and in general AI was found to be adequate for the characterization of dust loadings over the eastern Mediterranean on a climatological basis. A significant covariance between PM10 and AOT was observed during VET as well, indicating that AOT levels from AERONET may be estimated by PM10 levels at the surface. Surface measurements are thus crucial for the validation of remote sensing measurements and hence are a powerful tool for the investigation of the impact of aerosols on climate.

  10. Surface errors without semantic impairment in acquired dyslexia: a voxel-based lesion-symptom mapping study.

    PubMed

    Binder, Jeffrey R; Pillay, Sara B; Humphries, Colin J; Gross, William L; Graves, William W; Book, Diane S

    2016-05-01

    Patients with surface dyslexia have disproportionate difficulty pronouncing irregularly spelled words (e.g. pint), suggesting impaired use of lexical-semantic information to mediate phonological retrieval. Patients with this deficit also make characteristic 'regularization' errors, in which an irregularly spelled word is mispronounced by incorrect application of regular spelling-sound correspondences (e.g. reading plaid as 'played'), indicating over-reliance on sublexical grapheme-phoneme correspondences. We examined the neuroanatomical correlates of this specific error type in 45 patients with left hemisphere chronic stroke. Voxel-based lesion-symptom mapping showed a strong positive relationship between the rate of regularization errors and damage to the posterior half of the left middle temporal gyrus. Semantic deficits on tests of single-word comprehension were generally mild, and these deficits were not correlated with the rate of regularization errors. Furthermore, the deep occipital-temporal white matter locus associated with these mild semantic deficits was distinct from the lesion site associated with regularization errors. Thus, in contrast to patients with surface dyslexia and semantic impairment from anterior temporal lobe degeneration, surface errors in our patients were not related to a semantic deficit. We propose that these patients have an inability to link intact semantic representations with phonological representations. The data provide novel evidence for a post-semantic mechanism mediating the production of surface errors, and suggest that the posterior middle temporal gyrus may compute an intermediate representation linking semantics with phonology.

  11. Effects of Surface Albedo on Smoke Detection Through Geostationary Satellite Imagery in the Hazard Mapping System (HMS)

    NASA Astrophysics Data System (ADS)

    Salemi, A.; Ruminski, M. G.

    2012-12-01

    The Satellite Analysis Branch (SAB) of NOAA/NESDIS uses geostationary and polar orbiting satellite imagery to identify fires and smoke throughout the continental United States. The fires and smoke are analyzed daily on the Hazard Mapping System (HMS) and made available via the internet in various formats. Analysis of smoke plumes generated from wildfires, agricultural and prescribe burns is performed with single channel visible imagery primarily from NOAA's Geostationary Operational Environmental Satellite (GOES) animations. Identification of smoke in visible imagery is complicated by the presence of clouds, the viewing angle produced by the sun, smoke, satellite geometry, and the surface albedo of the ground below the smoke among other factors. This study investigates the role of surface albedo in smoke detection. LIght Detection And Ranging (LIDAR) instruments are capable of detecting smoke and other aerosols. Through the use of ground and space based LIDAR systems in areas of varying albedo a relationship between the subjective analyst drawn smoke plumes versus those detected by LIDAR is established. The ability to detect smoke over regions of higher albedo (brighter surface, such as grassland, scrub and desert) is diminished compared to regions of lower albedo (darker surface, such as forest and water). Users of the HMS smoke product need to be aware of this limitation in smoke detection in areas of higher albedo.

  12. Infrared thermal mapping of the Martian surface and atmosphere - First results

    NASA Technical Reports Server (NTRS)

    Kieffer, H. H.; Martin, T. Z.; Chase, S. C., Jr.; Miner, E. D.; Palluconi, F. D.; Muench, G.; Neugebauer, G.

    1976-01-01

    The Viking infrared thermal mapper measures the thermal emission of the Martian surface and atmosphere and the total reflected sunlight. With the high resolution and dense coverage being achieved, planetwide thermal structure is apparent at large and small scales. The thermal behavior of the best-observed areas, the landing sites, cannot be explained by simple homogeneous models. The data contain clear indications for the relevance of additional factors such as detailed surface texture and the occurrence of clouds. Areas in the polar night have temperatures distinctly lower than the CO2 condensation point at the surface pressure. This observation implies that the annual atmospheric condensation is less than previously assumed and that either thick CO2 clouds exist at the 20-kilometer level or that the polar atmosphere is locally enriched by noncondensable gases.

  13. Infrared thermal mapping of the martian surface and atmosphere: first results.

    PubMed

    Kieffer, H H; Chase, S C; Miner, E D; Palluconi, F D; Münch, G; Neugebauer, G; Martin, T Z

    1976-08-27

    The Viking infrared thermal mapper measures the thermal emission of the martian surface and atmosphere and the total reflected sunlight. With the high resolution and dense coverage being achieved, planetwide thermal structure is apparent at large and small scales. The thermal behavior of the best-observed areas, the landing sites, cannot be explained by simple homogeneous models. The data contain clear indications for the relevance of additional factors such as detailed surface texture and the occurrence of clouds. Areas in the polar night have temperatures distinctly lower than the CO(2) condensation point at the surface pressure. This observation implies that the annual atmospheric condensation is less than previously assumed and that either thick CO(2) clouds exist at the 20-kilometer level or that the polar atmosphere is locally enriched by noncondensable gases.

  14. Mapping Surface Cover Parameters Using Aggregation Rules and Remotely Sensed Cover Classes. Version 1.9

    NASA Technical Reports Server (NTRS)

    Arain, Altaf M.; Shuttleworth, W. James; Yang, Z-Liang; Michaud, Jene; Dolman, Johannes

    1997-01-01

    A coupled model, which combines the Biosphere-Atmosphere Transfer Scheme (BATS) with an advanced atmospheric boundary-layer model, was used to validate hypothetical aggregation rules for BATS-specific surface cover parameters. The model was initialized and tested with observations from the Anglo-Brazilian Amazonian Climate Observational Study and used to simulate surface fluxes for rain forest and pasture mixes at a site near Manaus in Brazil. The aggregation rules are shown to estimate parameters which give area-average surface fluxes similar to those calculated with explicit representation of forest and pasture patches for a range of meteorological and surface conditions relevant to this site, but the agreement deteriorates somewhat when there are large patch-to-patch differences in soil moisture. The aggregation rules, validated as above, were then applied to remotely sensed 1 km land cover data set to obtain grid-average values of BATS vegetation parameters for 2.8 deg x 2.8 deg and 1 deg x 1 deg grids within the conterminous United States. There are significant differences in key vegetation parameters (aerodynamic roughness length, albedo, leaf area index, and stomatal resistance) when aggregate parameters are compared to parameters for the single, dominant cover within the grid. However, the surface energy fluxes calculated by stand-alone BATS with the 2-year forcing, data from the International Satellite Land Surface Climatology Project (ISLSCP) CDROM were reasonably similar using aggregate-vegetation parameters and dominant-cover parameters, but there were some significant differences, particularly in the western USA.

  15. Preparation of Spectra for Surface Mapping with Doppler Imaging of a Peculiar Star V776 Her

    NASA Astrophysics Data System (ADS)

    Gürsoytrak, Hande; Gürol, Birol

    2016-04-01

    Our Sun is the only star that we can see thoroughly the surface of it. Chemically peculiar stars show anomalous abundances of some elements such as silicium, chromium and strontium. Doppler imaging is a useful technique for reconstructing the several structures on the surfaces of peculiar stars. We analyze our spectral observations as a preparation to Doppler imaging and compare V776 Her’s observational spectra with the synthetic spectra that we produce with using the SPECTRUM code. The differences between the observational spectra and the synthetic spectra is discussed in this work.

  16. Active control and spatial mapping of mid-infrared propagating surface plasmons.

    PubMed

    Ribaudo, T; Shaner, E A; Howard, S S; Gmachl, C; Wang, X J; Choa, F-S; Wasserman, D

    2009-04-27

    Periodic arrays of subwavelength apertures in metal films have been shown to exhibit strongly enhanced transmission at wavelengths determined by the periodicity of the film as well as the optical properties of the metal and surrounding dielectric material. Here we investigate the coupling between such a grating and a Quantum Cascade Laser. By actively tuning the optical properties of our grating, we control the coupling of laser light to the plasmonic structure, switching our grating from a predominantly transmitting state to a state that allows coupling to propagating surface waves, which can then be imaged on the metallic surface.

  17. Microscopic calculation of interacting boson model parameters by potential-energy surface mapping

    SciTech Connect

    Bentley, I.; Frauendorf, S.

    2011-06-15

    A coherent state technique is used to generate an interacting boson model (IBM) Hamiltonian energy surface which is adjusted to match a mean-field energy surface. This technique allows the calculation of IBM Hamiltonian parameters, prediction of properties of low-lying collective states, as well as the generation of probability distributions of various shapes in the ground state of transitional nuclei, the last two of which are of astrophysical interest. The results for krypton, molybdenum, palladium, cadmium, gadolinium, dysprosium, and erbium nuclei are compared with experiment.

  18. Phonon surface mapping of graphite: Disentangling quasi-degenerate phonon dispersions

    NASA Astrophysics Data System (ADS)

    Grüneis, A.; Serrano, J.; Bosak, A.; Lazzeri, M.; Molodtsov, S. L.; Wirtz, L.; Attaccalite, C.; Krisch, M.; Rubio, A.; Mauri, F.; Pichler, T.

    2009-08-01

    The two-dimensional mapping of the phonon dispersions around the K point of graphite by inelastic x-ray scattering is provided. The present work resolves the longstanding issue related to the correct assignment of transverse and longitudinal phonon branches at K . We observe an almost degeneracy of the three TO-, LA-, and LO-derived phonon branches and a strong phonon trigonal warping. Correlation effects renormalize the Kohn anomaly of the TO mode, which exhibits a trigonal warping effect opposite to that of the electronic band structure. We determined the electron-phonon coupling constant to be 166(eV/Å)2 in excellent agreement to GW calculations. These results are fundamental for understanding angle-resolved photoemission, double-resonance Raman and transport measurements of graphene-based systems.

  19. Linking Landsat observations with MODIS derived Land Surface Phenology data to map agricultural expansion and contraction in Russia

    NASA Astrophysics Data System (ADS)

    Caliskan, S.; de Beurs, K.

    2010-12-01

    Direct human impacts on the land surface are especially pronounced in agricultural regions that cover a substantial portion of the global land surface: 12% of the terrestrial surface is under active agricultural management. Crops display phenologies distinct from natural vegetation; the growing seasons are often shifted in time, crop establishment is generally fast and the vegetation is rapidly removed at harvest. Previously we have demonstrated that agricultural land abandonment alters land surface phenology sufficiently to be detectable from a time series of coarse resolution imagery. With land surface phenology models based on accumulated growing degree-days (AGDD) and AVHRR NDVI, we demonstrated that abandoned croplands covered with native grasses and weeds typically greened-up and peaked sooner than active croplands. Here we present an expansion of these analyses for the MODIS time period with the ultimate goal to map agricultural abandonment and expansion in European Russia from 2000 to 2010. We used the 8-day, 1km L3 Land Surface Temperature data (MOD11A2) to generate the accumulated growing degree days and the 16-day L3 Nadir BRDF-Adjusted reflectance data at 500m resolution (MCD43A4) to calculate NDVI. We calculated phenological metrics based on three methods: 1) Double-logistic models such as those applied to produce the standard MODIS phenology product (MOD12Q2); 2) A combination of NDII and NDVI; this method has been shown to provide start/end of season measurement closest to field observations in snowy areas; and 3) A quadratic model linking accumulated growing degree days and vegetation indices which we successfully applied in agricultural areas of Kazakhstan and semi-arid Africa. We selected Landsat imagery for two vastly different regions in Russia and present a Landsat-guided probabilistic detection of abandoned and active croplands for all available years of the MODIS image time series (2000-2010). For each region, we selected at least two images

  20. RAPID SPATIAL MAPPING OF CHEMICALS DISPERSED ACROSS SURFACES USING AN AUTOSAMPLER/DART/TOFMS

    EPA Science Inventory

    Rapid identification and semi-quantitation of chemicals spatially dispersed and

    deposited on surfaces by accidental, deliberate, or weather-related events requires analysis of

    hundreds of samples, usually obtained by sampling with wipes. Hand-held devices used on-si...

  1. Application of classification methods for mapping Mercury's surface composition: analysis on Rudaki's Area

    NASA Astrophysics Data System (ADS)

    Zambon, F.; De Sanctis, M. C.; Capaccioni, F.; Filacchione, G.; Carli, C.; Ammanito, E.; Friggeri, A.

    2011-10-01

    During the first two MESSENGER flybys (14th January 2008 and 6th October 2008) the Mercury Dual Imaging System (MDIS) has extended the coverage of the Mercury surface, obtained by Mariner 10 and now we have images of about 90% of the Mercury surface [1]. MDIS is equipped with a Narrow Angle Camera (NAC) and a Wide Angle Camera (WAC). The NAC uses an off-axis reflective design with a 1.5° field of view (FOV) centered at 747 nm. The WAC has a re- fractive design with a 10.5° FOV and 12-position filters that cover a 395-1040 nm spectral range [2]. The color images can be used to infer information on the surface composition and classification meth- ods are an interesting technique for multispectral image analysis which can be applied to the study of the planetary surfaces. Classification methods are based on clustering algorithms and they can be divided in two categories: unsupervised and supervised. The unsupervised classifiers do not require the analyst feedback, and the algorithm automatically organizes pixels values into classes. In the supervised method, instead, the analyst must choose the "training area" that define the pixels value of a given class [3]. Here we will describe the classification in different compositional units of the region near the Rudaki Crater on Mercury.

  2. Co-incident 3D mapping of sea ice surface elevation and ice draft in the Beaufort Sea

    NASA Astrophysics Data System (ADS)

    Doble, M. J.; Forsberg, R.; Haas, C.; Hanson, S.; Hendriks, S.; Martin, T.; Skourup, H.; Wadhams, P.

    2007-12-01

    Co-incident measurements of sea ice freeboard, thickness and draft were made during the Applied Physics Laboratory Ice Station (APLIS), in April 2007. The campaign was the first time that full three-dimensional mapping of sea ice freeboard and sea ice draft have been achieved simultaneously. Freeboard was measured across a swath width of 300 m at 1 m spatial resolution, using a laser profilometer flown aboard a Twin Otter aircraft. Ice draft was measured across a swath width of approximately 80 m at 0.5 m spatial resolution, using a Gavia AUV fitted with a GeoAcoustics phase-measuring swath sonar. Ice thickness was also measured along co-incident tracks using a helicopter-borne electromagnetic sounding instrument (HEM bird). The laser profilometer and AUV-mounted sonar rely on the assumption of isostatic balance when deriving ice thickness estimates from the ice surface and underside profiles, while the HEM bird records both surfaces simultaneously and independently, though averaging over a significant footprint (30 m) for the underside of the ice. Though the extent of the APLIS dataset was limited by the radius of AUV operations, the dataset will significantly improve our understanding of ice volume in deformed ice areas, particularly our understanding of the contribution of ridges and rubble fields to total Arctic ice volume, their isostatic balance and questions of block-scale porosity. The data will serve to better constrain the effects of porosity and footprint on the operational HEM measurements and, conversely, the HEM measurements will allow conclusions about the impact of the isostatic balance assumption on ice thickness estimates derived from mapping of one surface.

  3. Surface mineral mapping at Virginia City and Steamboat Springs, Nevada with multi-wavelength infrared remote sensing image data

    NASA Astrophysics Data System (ADS)

    Vaughan, R. Greg

    The purpose of this study was to use a combination of high spatial resolution airborne visible, near infrared, short wave infrared (VNIR/SWIR) and thermal infrared (TIR) image data to remotely identify and map exposed alteration minerals around both active and ancient hydrothermal systems, and the mineral by-products of weathered mine tailings. Three case study areas were evaluated: (1) Steamboat Springs, as an active geothermal system; (2) Geiger Grade and Virginia City, as ancient hydrothermal systems; and (3) Virginia City, as a historic mining district. Remote sensing data from the Airborne Visible Infrared Imaging Spectrometer (AVIRIS), as well as data from newly developed airborne imaging spectrometers: SpecTIR Corporation's airborne hyperspectral imager (HyperSpecTIR), the MODIS-ASTER airborne simulator (MASTER), and the Spatially Enhanced Broadband Array Spectrograph System (SEBASS) were acquired and processed into mineral maps based on the unique spectral signatures of image pixels. VNIR/SWIR and TIR field spectrometer data were collected for both calibration and validation of the remote data sets, and field sampling, laboratory spectral analyses and XRD analyses were made to corroborate the surface mineralogy identified by spectroscopic methods. In all of the case study areas the minerals mapped included sinter, quartz/chalcedony, albite, calcite, dolomite, hydrous sulfate minerals (tamarugite, alunogen, gypsum and hexahydrite), jarosite, hematite, goethite, alunite, pyrophyllite, kaolinite, montmorillonite/muscovite, and chlorite. The results were synthesized into single thematic mineral maps and indicate that the combination of multi-channel infrared remote sensing data is an effective technique for the unique identification and mapping of weathering and alteration minerals that are characteristic of active and fossil hydrothermal systems, as well as acid mine drainage potential. This study provides many examples of the advantages of high spatial and

  4. Monthly Maps of Sea Surface Height in the North Atlantic and Zonal Indices for the Gulf Stream Using TOPEX/Poseidon Altimeter Data

    NASA Technical Reports Server (NTRS)

    Singh, Sandipa; Kelly, Kathryn A.

    1997-01-01

    Monthly Maps of sea surface height are constructed for the North Atlantic Ocean using TOPEX/Poseidon altimeter data. Mean sea surface height is reconstructed using a weighted combination of historical, hydrographic data and a synthetic mean obtained by fitting a Gaussian model of the Gulf Stream jet to altimeter data. The resultant mean shows increased resolution over the hydrographic mean, and incorporates recirculation information that is absent in the synthetic mean. Monthly maps, obtained by adding the mean field to altimeter sea surface height residuals, are used to derive a set of zonal indices that describe the annual cycle of meandering as well as position and strength of the Gulf Stream.

  5. Mapping of near surface fold structures with GPR and ERT near Steinbrunn (Northern Burgenland, Austria)

    NASA Astrophysics Data System (ADS)

    Kreutzer, Ingrid; Chwatal, Werner; Häusler, Hermann; Scheibz, Jürgen; Steirer, Fritz

    2014-05-01

    In the transition zone between the southern Vienna Basin and the Eisenstadt basin, close to Wr. Neustadt, spectacular fold structures are exposed in the former sand pit of Steinbrunn. The succession of Upper Pannonian age consists of decimetre to meter thick sandy, silty and clayey beds, which are overlain by sandstone beds (Grundtner et al., 2009). The anticline and syncline structures were interpreted as of gravitational origin by Exner et al. (2009), and reinterpreted as of tectonic origin by Häusler (2012a). In order to gain a more detailed insight to the three dimensional distribution and orientation of the folds high resolution geophysics such as electrical resistivity tomography (ERT), ground penetrating radar (GPR) and electromagnetics (EM) were applied to map the surroundings of the sandpit. The ERT- and EM-profiles show that the uppermost layer is more clayey northwest and sandier southeast of the sandpit. This is important for the GPR because clay attenuates the radar signals and therefore no clear layering of the subsurface could be mapped in these areas. In order to directly compare ERT and GPR results with the lithology of the fold structures observed in the sandpit, a reference profile on top of the 140 m long wall of the sandpit was performed. Both methods clearly reveal fold structures paralleling the folded Pannonian strata of the outcrop. While the GPR data displays boundaries and their geometry in the succession, the resistivities in the ERT portrays a more smoothened image of the observed fold structure. In almost all GPR profiles wavelike structures are visible with axes in northern direction and dome-shaped structures with axes in eastern direction, deepening towards the west. In conclusion this pattern is comparable to sections of rounded buckle folds. Although there are clayey areas wave-like and dome-like reflections can be followed in the GPR profiles over a distance of several hundred meters. This is confirmed by the ERT profiles

  6. Topography and Mechanical Property Mapping of International Simple Glass Surfaces with Atomic Force Microscopy

    SciTech Connect

    Pierce, Eric M

    2014-01-01

    Quantitative Nanomechanical Peak Force (PF-QNM) TappingModeTM atomic force microscopy measurements are presented for the first time on polished glass surfaces. The PF-QNM technique allows for topography and mechanical property information to be measured simultaneously at each pixel. Results for the international simple glass which represents a simplified version of SON68 glass suggests an average Young s modulus of 78.8 15.1 GPa is within the experimental error of the modulus measured for SON68 glass (83.6 2 GPa) with conventional approaches. Application of the PF-QNM technique will be extended to in situ glass corrosion experiments with the goal of gaining atomic-scale insights into altered layer development by exploiting the mechanical property differences that exist between silica gel (e.g., altered layer) and pristine glass surface.

  7. Eddy covariance mapping and quantification of surface CO2 leakage fluxes

    SciTech Connect

    Lewicki, J.L.; Hilley, G.E.

    2009-08-01

    We present eddy covariance measurements of net CO{sub 2} flux (F{sub c}) made during a controlled release of CO{sub 2} (0.3 t d{sup -1} from 9 July to 7 August 2008) from a horizontal well {approx}100 m in length and {approx}2.5 m in depth located in an agricultural field in Bozeman, MT. We isolated fluxes arising from the release (F{sub cr}) by subtracting fluxes corresponding to a model for net ecosystem exchange from F{sub c}. A least-squares inversion of 611 F{sub cr} and corresponding modeled footprint functions recovered the location, length, and magnitude of the surface CO{sub 2} flux leakage signal, although high wavenumber details of the signal were poorly resolved. The estimated total surface CO{sub 2} leakage rate (0.32 t d{sup ?1}) was within 7% of the release rate.

  8. Sea surface temperature of the coastal zones of France. Heat Capacity Mapping Mission (HCMM)

    NASA Technical Reports Server (NTRS)

    Deschamps, P. Y.; Frouin, R.; Cassanet, G.; Verger, F. (Principal Investigator)

    1979-01-01

    The author has identified the following significant results. HCMM data analysis shows some mesoscale features which were previously expected to occur: summer coastal upwellings in the Gulf of Lions, tidal fronts bordering the English Channel, and cooler surface waters at the continental shelf break. The analysis of the spectral variance density spectra show that the interpretation of the data usually is limited by the HCMM radiometric performance (noise levels) at wavenumbers below 5 km in the oceanic areas; from this analysis it may also be concluded that a decrease of the radiometric noise level down to 0.1 k against an increase of the ground resolution up to 2 km would give a better optimum of the radiometric performances in the oceanic areas. HCMM data appear to be useful for analysis of the sea surface temperature field, particularly in the very coastal area by profiting from the ground resolution of 500 m.

  9. Mesoscale Near-Surface Wind Speed Variability Mapping with Synthetic Aperture Radar

    PubMed Central

    Young, George; Sikora, Todd; Winstead, Nathaniel

    2008-01-01

    Operationally-significant wind speed variability is often observed within synthetic aperture radar-derived wind speed (SDWS) images of the sea surface. This paper is meant as a first step towards automated distinguishing of meteorological phenomena responsible for such variability. In doing so, the research presented in this paper tests feature extraction and pixel aggregation techniques focused on mesoscale variability of SDWS. A sample of twenty eight SDWS images possessing varying degrees of near-surface wind speed variability were selected to serve as case studies. Gaussian high- and low-pass, local entropy, and local standard deviation filters performed well for the feature extraction portion of the research while principle component analysis of the filtered data performed well for the pixel aggregation. The findings suggest recommendations for future research.

  10. Evaluation of Surface Energy Balance models for mapping evapotranspiration using very high resolution airborne remote sensing data

    NASA Astrophysics Data System (ADS)

    Paul, George

    Agriculture is the largest (90%) consumer of all fresh water in the world. The consumptive use of water by vegetation represented by the process evapotranspiration (ET) has a vital role in the dynamics of water, carbon and energy fluxes of the biosphere. Consequently, mapping ET is essential for making water a sustainable resource and also for monitoring ecosystem response to water stress and changing climate. Over the past three decades, numerous thermal remote sensing based ET mapping algorithms were developed and these have brought a significant theoretical and technical advancement in the spatial modeling of ET. Though these algorithms provided a robust, economical, and efficient tool for ET estimations at field and regional scales, yet the uncertainties in flux estimations were large, making evaluation a difficult task. The main objective of this study was to evaluate and improve the performance of widely used remote sensing based energy balance models, namely: the Surface Energy Balance Algorithm for Land (SEBAL), Mapping Evapotranspiration at high Resolution and with Internalized Calibration (METRIC), and Surface Energy Balance System (SEBS). Data used in this study was collected as part of a multi-disciplinary and multi-institutional field campaign BEAREX (Bushland Evapotranspiration and Agricultural Remote Sensing Experiment) that was conducted during 2007 and 2008 summer cropping seasons at the USDA-ARS Conservation and Production Research Laboratory (CPRL) in Bushland, Texas. Seventeen high resolution remote sensing images taken from multispectral sensors onboard aircraft and field measurements of the agro-meteorological variables from the campaign were used for model evaluation and improvement. Overall relative error measured in terms of mean absolute percent difference (MAPD) for instantaneous ET (mm h -1) were 22.7%, 23.2%, and 12.6% for SEBAL, METRIC, and SEBS, respectively. SEBAL and METRIC performances for irrigated fields representing higher ET

  11. Malaria parasite-inhibitory antibody epitopes on Plasmodium falciparum merozoite surface protein-1(19) mapped by TROSY NMR.

    PubMed

    Morgan, William D; Lock, Matthew J; Frenkiel, Thomas A; Grainger, Munira; Holder, Anthony A

    2004-11-01

    Plasmodium falciparum merozoite surface protein 1 (MSP1)(19), the C-terminal fragment of merozoite surface protein 1, is a leading candidate antigen for development of a vaccine against the blood stages of the malaria parasite. Many human and animal studies have indicated the importance of MSP1(19)-specific immune responses. Anti-MSP1(19) antibodies can prevent invasion of red blood cells by P. falciparum parasites in vitro. However, the fine specificity of anti-MSP1(19) antibodies is also important, as only a fraction of monoclonal antibodies (mAbs) have parasite-inhibitory activity in vitro. Human sera from malaria-endemic locations show strong MSP1(19) reactivity, but individual serum samples vary greatly in inhibitory activity. NMR is an excellent method for studying protein-protein interactions, and has been used widely to study binding of peptides representing known epitopes (as well as non-protein antigens) to antibodies and antibody fragments. The recent development of transverse relaxation optimized spectroscopy (TROSY) and related methods has significantly extended the maximum size limit of molecules that can be studied by NMR. TROSY NMR experiments produce high quality spectra of Fab complexes that allow the mapping of epitopes by the chemical shift perturbation technique on a complete, folded protein antigen such as MSP1(19). We studied the complexes of P. falciparum MSP1(19) with Fab fragments from three monoclonal antibodies. Two of these antibodies have parasite-inhibitory activity in vitro, while the third is non-inhibitory. NMR epitope mapping showed a close relationship between binding sites for the two inhibitory antibodies, distinct from the location of the non-inhibitory antibody. Together with a previously published crystal structure of the P. falciparum MSP1(19) complex with the Fab fragment of another non-inhibitory antibody, these results revealed a surface on MSP1(19) where inhibitory antibodies bind. This information will be useful in

  12. Mapping the downwelling atmospheric radiation at the Earth's surface: A research strategy

    NASA Technical Reports Server (NTRS)

    Raschke, E.

    1986-01-01

    A strategy is presented along with background material for determining downward atmospheric radiation at the Earth's surface on a regional scale but over the entire globe, using available information on the temperature and humidity of the air near the ground and at cloud base altitudes. Most of these parameters can be inferred from satellite radiance measurements. Careful validation of the derived radiances will be required using ground-based direct measurements of radiances, to avoid systematic biases of these derived field quantities.

  13. Mapping land surface emissivity from NDVI: Application to European, African, and South American areas

    SciTech Connect

    Valor, E.; Caselles, V.

    1996-09-01

    Temperature is an important magnitude for many environmental models: (1) energy and matter exchange between atmosphere and surface, (2) weather prediction, (3) global ocean circulation, (4) climatic change, etc. Several methods have been developed to obtain surface emissivity from satellite data. In this way the authors propose a theoretical model that relates the emissivity to the NDVI (normalized difference vegetation index) of a given surface and explains the experimental behavior observed by van de Griend and Owe. They can use it to obtain the emissivity in any thermal channel, but in this work they have focused on the 10.5- to 12.5-{micro}m region, where most thermal sensors on board satellites work at present.The model is applicable to areas with several soil and vegetation types an where the vegetation cover changes. From the theoretical model the authors have developed an operational methodology to obtain the effective emissivity combining satellite images and field measurements.The error of the methodology ranges from 0.5% (due to the experimental limitations of the field methods) to 2% (considering the case in which they have no information about the studied area). To check the general validity of the model, the authors have validated and applied it in different atmospheric environments and in areas with a different degree of roughness, i.e., from midlatitude (France, Argentina) to tropical (Sahel, Botswana) atmospheres, and from flat (La Mancha, Spain) to rough (Valencia, Spain) surfaces, and they have obtained an error of estimate of 0.6% on the emissivity.

  14. Mapping Ocean Surface Topography with a Synthetic-Aperture Interferometry Radar

    NASA Technical Reports Server (NTRS)

    Fu, Lee-Lueng; Rodriguez, Ernesto

    2006-01-01

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

  15. Combining a Spatial Model and Demand Forecasts to Map Future Surface Coal Mining in Appalachia

    PubMed Central

    Strager, Michael P.; Strager, Jacquelyn M.; Evans, Jeffrey S.; Dunscomb, Judy K.; Kreps, Brad J.; Maxwell, Aaron E.

    2015-01-01

    Predicting the locations of future surface coal mining in Appalachia is challenging for a number of reasons. Economic and regulatory factors impact the coal mining industry and forecasts of future coal production do not specifically predict changes in location of future coal production. With the potential environmental impacts from surface coal mining, prediction of the location of future activity would be valuable to decision makers. The goal of this study was to provide a method for predicting future surface coal mining extents under changing economic and regulatory forecasts through the year 2035. This was accomplished by integrating a spatial model with production demand forecasts to predict (1 km2) gridded cell size land cover change. Combining these two inputs was possible with a ratio which linked coal extraction quantities to a unit area extent. The result was a spatial distribution of probabilities allocated over forecasted demand for the Appalachian region including northern, central, southern, and eastern Illinois coal regions. The results can be used to better plan for land use alterations and potential cumulative impacts. PMID:26090883

  16. Curie isotherm map of Scotia Arc from near surface magnetic anomaly data

    NASA Astrophysics Data System (ADS)

    Catalán, Manuel

    2016-04-01

    The opening of the Drake Passage, situated between South America and Antarctica, represents the final stage of the fragmentation of Gondwana supercontinent. It led to the Scotia Arc formation, bordering the Scotia Sea, which is surrounded by fragments of the former continental connection. It is currently composed of Scotia and Sandwich Plates. Shackleton Fracture Zone constitutes its sinistral transpressive western boundary and it is a key structure that accommodates former Phoenix and Scotia Plates' differential movement. The formation of the Drake Passage and the Scotia Sea is considered of great importance to ocean circulation, as it allows the establishment of the Antarctic Circumpolar Current that isolated the Antarctic continent, with strong implications for climate and global changes. Thermal structure of the Earth's crust is one of the main parameters controlling geodynamic processes. There is few information regarding heat flow values on Scotia arc. These values are mainly located in its westernmost, southern and easternmost part, which are not enough to extract conclusions regarding lithospheric thickness variations and asthenospheric flow. Taking advantage of the World Digital Magnetic Anomaly Map Project's compilation we have extracted magnetic anomaly data which fall inside the Scotia Arc and surrounding areas. This magnetic anomaly picture provides the best representation of magnetic properties to date. We propose to use spectral methods on this regional magnetic compilation to obtain depth to the bottom of magnetic sources as a proxy to infer Curie depth and heat flow distribution in the Scotia Sea.

  17. Surface circulation in the Iroise Sea (western Brittany) derived from high resolution current mapping by HF radars

    NASA Astrophysics Data System (ADS)

    Sentchev, Alexei; Forget, Philippe; Barbin, Yves; Marié, Louis; Ardhuin, Fabrice

    2010-05-01

    The use of high frequency radar (HFR) systems for near-real-time coastal ocean monitoring necessities that short time scale motions of the radar-derived velocities are better understood. While the ocean radar systems are able to describe coastal flow patterns with unprecedented details, the data they produce are often too sparse or gappy for applications such as the identification of coherent structures and fronts or understanding transport and mixing processes. In this study, we address two challenges. First, we report results from the HF radar system (WERA) which is routinely operating since 2006 on the western Brittany coast to monitor surface circulation in the Iroise Sea, over an area extending up to 100 km offshore. To obtain more reliable records of vector current fields at high space and time resolution, the Multiple Signal Classification (MUSIC) direction finding algorithm is employed in conjunction with the variational interpolation (2dVar) of radar-derived velocities. This provides surface current maps at 1 km spacing and time resolution of 20 min. Removing the influence of the sea state on radar-derived current measurements is discussed and performed on some data sequences. Second, we examine in deep continuous 2d velocity records for a number of periods, exploring the different modes of variability of surface currents in the region. Given the extent, duration, and resolution of surface current velocity measurements, new quantitative insights from various time series and spatial analysis on higher frequency kinematics will be discussed. By better characterizing the full spectrum of flow regimes that contribute to the surface currents and their shears, a more complete picture of the circulation in the Iroise Sea can be obtained.

  18. Rayleigh and Love wave phase velocity maps of Iceland from combined ambient noise and teleseismic surface wave analysis.

    NASA Astrophysics Data System (ADS)

    Harmon, N.

    2014-12-01

    Iceland is one of the few regions where ridge-plume interaction can be examined with a terrestrial seismic array. Velocity structure from broadband surface wave dispersion measurements can be used to constrain the complicated crustal and upper mantle structure caused by the plume enhanced rifting activity. Here I use data from the ICEMELT and HOTSPOT arrays on Iceland to generate phase velocity dispersion maps of both Rayleigh and Love waves from ambient noise cross correlation and teleseismic events. I invert Rayleigh and Love wave dispersion observed from ambient noise for tomographic velocity structure. For teleseismic Rayleigh waves I use the two-plane wave approximation array-based method of Forsyth and Li [2005]. I also develop and adapt this method for teleseismic Love waves. This requires additional preprocessing of the data to estimate the amplitude and phase for teleseismic Love waves. Specifically, for each station, the vertical component phase observation of the fundamental mode Rayleigh is used to predict and remove the horizontal components of Rayleigh waves. Then I invert for the maximum amplitude and apparent back azimuth at each period of interest of the Love wave from the transverse and radial components. The amplitude and phase measurement is then inverted for phase velocity structure using a modified version of the two plane-wave approximation. Preliminary results indicate a low velocity region at short periods (8-15 s) in both the Rayleigh and Love wave phase velocity maps beneath the active volcanic centers in the middle of the island. At longer periods (20-125 s) a low velocity region is visible beneath central Iceland. The velocity minimum is located to the north of Iceland in the Rayleigh wave maps. These observations are consistent with previous studies in the region.

  19. Documentation for emergency condition mapping of Decorated historic surfaces at the Caid Residence, the Kasbah of Taourirt (Ouarzazate, Morocco)

    NASA Astrophysics Data System (ADS)

    Percy, K.; Ouimet, C.; Ward, S.; Santana Quintero, M.; Cancino, C.; Wong, L.; Marcus, B.; Whittaker, S.; Boussalh, M.

    2015-08-01

    As it is broadly understood, recording serves as a basis for the diagnosis, treatment and preservation of historic places and contributes to record our built cultural heritage for posterity. This work is not a stand-alone practice but a part of the overall conservation process of cultural heritage at imminent risk of irreversible damage. Recording of heritage places should be directly related to the needs, skills and the technology that are available to the end users that are responsible for the management and care of these sites. They should be selected in a way that the future managers of these sites can also access and use the data collected. This paper explains an innovative heritage recording approach applied by the Getty Conservation Institute (GCI) and Carleton Immersive Media Studio (CIMS) in the documentation of historic decorated surfaces at the Caïd Residence, located at Tighermt (Kasbah) Taourirt in Ouarzazate, Morocco; as part of a collaborative project between the GCI and the Centre de Conservation et Réhabilitation du Patrimoine Architectural des Zones Atlasiques et Sub-Atlasiques (CERKAS) to rehabilitate the entire architectural ensemble. The selected recording techniques were used for the rapid mapping of conditions of the decorated surfaces at the Caïd Residence using international standards. The resulting work is being used by GCI staff, consultants and CERKAS team to conduct emergency stabilization and protection measures for these important decorated surfaces.

  20. Feasibility of correlation mapping optical coherence tomography (cmOCT) for anti-spoof sub-surface fingerprinting.

    PubMed

    Zam, Azhar; Dsouza, Roshan; Subhash, Hrebesh M; O'Connell, Marie-Louise; Enfield, Joey; Larin, Kirill; Leahy, Martin J

    2013-09-01

    We propose the use of correlation mapping optical coherence tomography (cmOCT) to deliver additional biometrics associated with the finger that could complement existing fingerprint technology for law enforcement applications. The current study extends the existing fingerprint paradigm by measuring additional biometrics associated with sub-surface finger tissue such as sub-surface fingerprints, sweat glands, and the pattern of the capillary bed to yield a user-friendly cost effective and anti-spoof multi-mode biometric solution associated with the finger. To our knowledge no other method has been able to capture sub-surface fingerprint, papillary pattern and horizontal vessel pattern in a single scan or to show the correspondence between these patterns in live adult human fingertip. Unlike many current technologies this approach incorporates 'liveness' testing by default. The ultimate output is a biometric module which is difficult to defeat and complements fingerprint scanners that currently are used in border control and law enforcement applications. PMID:23616445

  1. Geologic mapping of near-surface sediments in the northern Mississippi Embayment, McCracken County, KY

    SciTech Connect

    Sexton, Joshua L; Fryar, Alan E; Greb, s F

    2006-04-01

    POSTER: The Jackson Purchase region of western Kentucky consists of Coastal Plain sediments near the northern margin of the Mississippi Embayment. Within this region is the Paducah Gaseous Diffusion Plant (PGDP), a uranium enrichment facility operated by the US Department of Energy. At PGDP, a Superfund site, soil and groundwater studies have provided subsurface lithologic data from hundreds of monitoring wells and borings. Despite preliminary efforts by various contractors, these data have not been utilized to develop detailed stratigraphic correlations of sedimentary units across the study area. In addition, sedimentary exposures along streams in the vicinityof PGDP have not been systematically described beyond the relatively simple geologic quadrangle maps published by the US Geological Survey in 1966-67. This study integrates lithologic logs, other previous site investigation data, and outcrop mapping to provide a compilation of near-surface lithologic and stratigraphic data for the PGDP area. A database of borehole data compiled during this study has been provided to PGDP for future research and archival.

  2. Development of micro-beam NRA for hydrogen mapping: Observation of fatigue-fractured surface of glassy alloys

    NASA Astrophysics Data System (ADS)

    Sekiba, D.; Yonemura, H.; Ogura, S.; Matsumoto, M.; Kitaoka, Y.; Yokoyama, Y.; Matsuzaki, H.; Narusawa, T.; Fukutani, K.

    2011-04-01

    A micro-beam NRA system by means of a resonant nuclear reaction of 1H( 15N, αγ) 12C has been developed at the beam line in MALT, University of Tokyo. The beam optics was analyzed in terms of the phase diagram. By carefully suppressing the spherical aberration of the final quadrupole magnetic lens, the 15N beam at the energy of 6.4 MeV was focused on targets with a size of 17 μm × 30 μm. For the precise positioning of the sample and beam spot, a combination of the mirror and optical microscope was adopted, so that the hydrogen concentration can be measured at a desirable position of the sample. With this new system, the hydrogen concentrations of fatigue-fractured surfaces of glassy alloys were determined from the viewpoint of the hydrogen embrittlement: Zr 50Cu 37Al 10Pd 3 and Zr 50Cu 40Al 10. Depth-resolved two-dimensional (2D) mapping of hydrogen concentration was performed in the area of 3 mm × 3 mm with an in-plane resolution of 150 μm. The maps taken at three different depths revealed that the hydrogen concentration is higher in the fatigue-fractured regions in both samples.

  3. Mapping surface alteration effects associated with hydrocarbon reservoirs at Gypsum Plain, Texas, and Cement, Oklahoma, using multispectral information

    SciTech Connect

    Carrerre, V.; Lang, H.R. ); Crawford, M.F. )

    1991-08-01

    Two test sites, Gypsum Plain, Texas, and Cement, Oklahoma, were selected to evaluate combined use of airborne visible/infrared imaging spectrometer (AVIRIS) and thermal infrared multispectral scanner (TIMS) for detection of alteration effects associated with hydrocarbon microseepage. Bleaching of redbuds, variations in carbonate cement, replacement of gypsum, exidation of iron, and changes in clay mineralogy may correlate spatially with oil and gas production and subsurface structures. Spectral features due to iron oxides, calcite, gypsum, smectite, and kaolinite can be mapped using AVIRIS image data, using various techniques such as ratios, scene-dependent log residuals, and scene-independent radioactive transfer approach using LOWTRAN7, and with TIMSA data using DSTRETCH. Poor signal-to-noise in the 2.0-2.4 {mu}m region limited the ability to map clay, gypsum, and carbonates both at Cement and Gypsum Plain, carbonate and quartz-rich sediments at Gypsum Plain, and differentiated soils developed on the Rush Spring Sandstone from soil derived from the Cloud Chief Formation at Cement. Combined spectral and photogeologic interpretation of coregistered AVIRIS, TIMS, and Landsat TM, and digital elevation data demonstrate the practical approaches for surface oil and gas exploration using presently operational commercial aircraft and future satellite systems.

  4. Three-body Coulomb problem probed by mapping the Bethe surface in ionizing ion-atom collisions.

    PubMed

    Moshammer, R; Perumal, A; Schulz, M; Rodríguez, V D; Kollmus, H; Mann, R; Hagmann, S; Ullrich, J

    2001-11-26

    The three-body Coulomb problem has been explored in kinematically complete experiments on single ionization of helium by 100 MeV/u C(6+) and 3.6 MeV/u Au(53+) impact. Low-energy electron emission ( E(e)<150 eV) as a function of the projectile deflection theta(p) (momentum transfer), i.e., the Bethe surface [15], has been mapped with Delta theta(p)+/-25 nanoradian resolution at extremely large perturbations ( 3.6 MeV/u Au(53+)) where single ionization occurs at impact parameters of typically 10 times the He K-shell radius. The experimental data are not in agreement with state-of-the-art continuum distorted wave-eikonal initial state theory.

  5. Silica-coated gold nanostars for surface-enhanced resonance Raman spectroscopy mapping of integrins in breast cancer cells

    NASA Astrophysics Data System (ADS)

    Fenn, Michael B.; Roki, Nikša.; Bashur, Chris

    2015-03-01

    Surface-Enhanced Resonance Raman Spectroscopy (SERRS) has great potential for improving cancer research and diagnosis. Capable of sub-femtomolar detection, and a high degree of multiplexing, SERRS is an attractive new technique for studying cancer biology. We have developed PEGylated silica-coated gold nanostars that can be tuned to match the Raman laser-light source wavelength, providing high-level SERRS/SERS enhancement when combined with various reporter molecules. Furthermore, the particles were conjugated with cyclo-RGDf/k peptide to investigate integrin expression of breast cancer cells using high-speed Raman mapping. We propose that this may provide a better understanding of the role of integrins in breast cancer invasiveness.

  6. Louisiana ground-water map no. 8; potentiometric surface, 1991, of the Carrizo-Wilcox Aquifer in northwestern Louisiana

    USGS Publications Warehouse

    Seanor, Ronald C.; Smoot, Charles W.

    1995-01-01

    In northwestern Louisiana, the Carrizo-Wilcox aquifer is the primary source of ground water within six parishes (Bossier, Caddo, De Soto, Natchitoches, Red River, and Sabine) and the secondary source in parts of three other parishes (Bienville, Claiborne, and Webster). Withdrawals from the aquifer increased from 4.7 Mgal/d (million gallons per day) in 1965 to 13.3 Mgal/d in 1990. A map of the potentiometric surface indicates that the altitudes of water levels in the Carrizo-Wilcox aquifer ranged from less than 100 feet to 300 feet above sea level in November and December 1991. The direction of ground-water flow within the aquifer generally is to the southeast and east or west to the Red River Valley.

  7. Global land surface albedo maps from MODIS using the Google Earth Engine

    NASA Astrophysics Data System (ADS)

    Mitraka, Zina; Benas, Nikolaos; Gorelick, Noel; Chrysoulakis, Nektarios

    2016-04-01

    The land surface albedo (LSA) is a critical physical variable, which influences the Earth's climate by affecting the energy budget and distribution in the Earth-atmosphere system. Its role is highly significant in both global and local scales; hence, LSA measurements provide a quantitative means for better constraining global and regional scale climate modelling efforts. The Moderate Resolution Imaging Spectroradiometer (MODIS) sensor, on board NASA's Terra and Aqua platforms, provides the parameters needed for the computation of LSA on an 8-day temporal scale and a variety of spatial scales (ranging between 0.5 - 5 km). This dataset was used here for the LSA estimation and its changes over the study area at 0.5 km spatial resolution. More specifically, the MODIS albedo product was used, which includes both the directional-hemispherical surface reflectance (black-sky albedo) and the bi-hemispherical surface reflectance (white-sky albedo). The LSA was estimated for the whole globe on an 8-day basis for the whole time period covered by MODIS acquisitions (i.e. 2000 until today). To estimate LSA from black-sky and white-sky albedos, the fraction of the diffused radiation is needed, a function of the Aerosol Optical Thickness (AOT). Required AOT information was acquired from the MODIS AOT product at 1̊ × 1̊ spatial resolution. Since LSA also depends on solar zenith angle (SZA), 8-day mean LSA values were computed as averages of corresponding LSA values for representative SZAs covering the 24-hour day. The estimated LSA was analysed in terms of both spatial and seasonal characteristics, while LSA changes during the period examined were assessed. All computation were performed using the Google Earth Engine (GEE). The GEE provided access to all the MODIS products needed for the analysis without the need of searching or downloading. Moreover, the combination of MODIS products in both temporal and spatial terms was fast and effecting using the GEE API (Application

  8. An imaging system for quantitive surface temperature mapping using two-color thermographic phosphors

    NASA Technical Reports Server (NTRS)

    Buck, Gregory M.

    1988-01-01

    A technique for obtaining detailed quantitative temperature distributions on test models in hypersonic wind tunnels is presented. This technique is based on the ratio of blue to green (450, 520 nm) emission from an UV (365 nm) excited phosphor coating. Separately filtered images are recorded from a three-tube color camera, utilizing off-the-shelf front-end video optics to discriminate wavelengths. Two demonstration studies in a 31-inch Mach 10 tunnel are discussed. One study presents the windward surface temperature-time history for a transatmospheric vehicle, and the other illustrates nosetip heating on a spherically blunted slender cone.

  9. Direct mapping of ion diffusion times on LiCoO2 surfaces with nanometer resolution

    SciTech Connect

    Guo, Senli; Jesse, Stephen; Kalnaus, Sergiy; Balke, Nina; Daniel, Claus; Kalinin, Sergei V

    2011-01-01

    The strong coupling between the molar volume and mobile ion concentration in ionically-conductive solids is used for spatially-resolved studies of ionic transport on the polycrystalline LiCoO2 surface by time-resolved spectroscopy. Strong variability between ionic transport at the grain boundaries and within the grains is observed, and the relationship between relaxation and hysteresis loop formation is established. The use of the strain measurements allows ionic transport be probed on the nanoscale, and suggests enormous potential for probing ionic materials and devices.

  10. Mapping ground surface deformation using temporarily coherent point SAR interferometry: Application to Los Angeles Basin

    USGS Publications Warehouse

    Zhang, L.; Lu, Zhiming; Ding, X.; Jung, H.-S.; Feng, G.; Lee, C.-W.

    2012-01-01

    Multi-temporal interferometric synthetic aperture radar (InSAR) is an effective tool to detect long-term seismotectonic motions by reducing the atmospheric artifacts, thereby providing more precise deformation signal. The commonly used approaches such as persistent scatterer InSAR (PSInSAR) and small baseline subset (SBAS) algorithms need to resolve the phase ambiguities in interferogram stacks either by searching a predefined solution space or by sparse phase unwrapping methods; however the efficiency and the success of phase unwrapping cannot be guaranteed. We present here an alternative approach - temporarily coherent point (TCP) InSAR (TCPInSAR) - to estimate the long term deformation rate without the need of phase unwrapping. The proposed approach has a series of innovations including TCP identification, TCP network and TCP least squares estimator. We apply the proposed method to the Los Angeles Basin in southern California where structurally active faults are believed capable of generating damaging earthquakes. The analysis is based on 55 interferograms from 32 ERS-1/2 images acquired during Oct. 1995 and Dec. 2000. To evaluate the performance of TCPInSAR on a small set of observations, a test with half of interferometric pairs is also performed. The retrieved TCPInSAR measurements have been validated by a comparison with GPS observations from Southern California Integrated GPS Network. Our result presents a similar deformation pattern as shown in past InSAR studies but with a smaller average standard deviation (4.6. mm) compared with GPS observations, indicating that TCPInSAR is a promising alternative for efficiently mapping ground deformation even from a relatively smaller set of interferograms. ?? 2011.

  11. Pole Photogrammetry with AN Action Camera for Fast and Accurate Surface Mapping

    NASA Astrophysics Data System (ADS)

    Gonçalves, J. A.; Moutinho, O. F.; Rodrigues, A. C.

    2016-06-01

    High resolution and high accuracy terrain mapping can provide height change detection for studies of erosion, subsidence or land slip. A UAV flying at a low altitude above the ground, with a compact camera, acquires images with resolution appropriate for these change detections. However, there may be situations where different approaches may be needed, either because higher resolution is required or the operation of a drone is not possible. Pole photogrammetry, where a camera is mounted on a pole, pointing to the ground, is an alternative. This paper describes a very simple system of this kind, created for topographic change detection, based on an action camera. These cameras have high quality and very flexible image capture. Although radial distortion is normally high, it can be treated in an auto-calibration process. The system is composed by a light aluminium pole, 4 meters long, with a 12 megapixel GoPro camera. Average ground sampling distance at the image centre is 2.3 mm. The user moves along a path, taking successive photos, with a time lapse of 0.5 or 1 second, and adjusting the speed in order to have an appropriate overlap, with enough redundancy for 3D coordinate extraction. Marked ground control points are surveyed with GNSS for precise georeferencing of the DSM and orthoimage that are created by structure from motion processing software. An average vertical accuracy of 1 cm could be achieved, which is enough for many applications, for example for soil erosion. The GNSS survey in RTK mode with permanent stations is now very fast (5 seconds per point), which results, together with the image collection, in a very fast field work. If an improved accuracy is needed, since image resolution is 1/4 cm, it can be achieved using a total station for the control point survey, although the field work time increases.

  12. Map presentation of changes in Europe's artificial surfaces for the periods 1990-2000 and 2000-2006

    NASA Astrophysics Data System (ADS)

    Feranec, Jan; Soukup, Tomas

    2013-06-01

    The landscapes of the world are constantly changing under the influence of human activities leading to the growth of artificial surfaces. The covering of soil by artificial surfaces is referred to as soil sealing. Aerial and satellite images or data derived from them (for instance CORINE land cover — CLC data used here) provide important information that makes it possible to assess the occurrence, area and rate of soil sealing. As the term sealed soil cannot be wholly identified with the content of the appropriate CLC classes, the term land cover flow urbanization (LCFU) will be used here. The essence of this study is the demonstration and documentation of the trends of the LCFU in Europe for the periods 1990-2000 and 2000-2006 on a single map. This may contribute to a better spatial awareness of the ongoing transformation of landscape under the effects of human activities in an pan-European context. Changes in the LCFU can be seen on a map, compiled from 3 × 3 km squares at an all-European scale, using colours and their hues, to fulfil the role both of identification and classification. The colour method employed makes it possible to perceive three groups of LCFU changes on two time horizons, that is, whether the rate of LCFU in 2000-2006 increased or remained the same (hues of red); or dropped compared to the 1990-2000 period (hues of light to dark blue). The third group represents the LCFU with rates higher or lower than the average (countries with changes recorded in only one time horizon are presented in dark and light magenta colours).

  13. Near-surface mapping using SH-wave and P-wave seismic land-streamer data acquisition in Illinois, U.S

    USGS Publications Warehouse

    Pugin, Andre J.M.; Larson, T.H.; Sargent, S.L.; McBride, J.H.; Bexfield, C.E.

    2004-01-01

    SH-wave and P-wave high-resolution seismic reflection combined with land-streamer technology provide 3D regional maps of geologic formations that can be associated with aquifers and aquitards. Examples for three study areas are considered to demonstrate this. In these areas, reflection profiling detected near-surface faulting and mapped a buried glacial valley and its aquifers in two settings. The resulting seismic data can be used directly to constrain hydrogeologic modeling of shallow aquifers.

  14. A tetrahedron-based endmember selection approach for urban impervious surface mapping.

    PubMed

    Wang, Wei; Yao, Xinfeng; Zhai, Junpeng; Ji, Minhe

    2014-01-01

    The pixel purity index (PPI) and two-dimensional (2-D) scatter plots are two popular techniques for endmember extraction in remote sensing spectral mixture analysis, yet both suffer from one major drawback, that is, the selection of a final set of endmembers has to endure a cumbersome process of iterative visual inspection and human intervention, especially when a spectrally-complex urban scene is involved. Within the conceptual framework of a V-H-L-S (vegetation-high albedo-low albedo-soil) model, which is expanded from the classic V-I-S (vegetation-impervious surface-soil) model, a tetrahedron-based endmember selection approach combined with a multi-objective optimization genetic algorithm (MOGA) was designed to identify urban endmembers from multispectral imagery. The tetrahedron defining the enclosing volume of MNF-transformed pixels in a three-dimensional (3-D) space was algorithmically sought, so that the tetrahedral vertices can ideally match the four components of the adopted model. A case study with Landsat Enhanced Thematic Mapper Plus (ETM+) satellite imagery in Shanghai, China was conducted to verify the validity of the method. The method performance was compared with those of the traditional PPI and 2-D scatter plots approaches. The results indicated that the tetrahedron-based endmember selection approach performed better in both accuracy and ease of identification for urban surface endmembers owing to the 3-D visualization analysis and use of the MOGA.

  15. Neutron-induced gamma-ray spectroscopy: simulations for chemical mapping of planetary surfaces

    SciTech Connect

    Brueckner, J.; Waenke, H.; Reedy, R.C.

    1986-01-01

    Cosmic rays interact with the surface of a planetary body and produce a cascade of secondary particles, such as neutrons. Neutron-induced scattering and capture reactions play an important role in the production of discrete gamma-ray lines that can be measured by a gamma-ray spectrometer on board of an orbiting spacecraft. These data can be used to determine the concentration of many elements in the surface of a planetary body, which provides clues to its bulk composition and in turn to its origin and evolution. To investigate the gamma rays made by neutron interactions, thin targets were irradiated with neutrons having energies from 14 MeV to 0.025 eV. By means of foil activation technique the ratio of epithermal to thermal neutrons was determined to be similar to that in the Moon. Gamma rays emitted by the targets and the surrounding material were detected by a high-resolution germanium detector in the energy range of 0.1 to 8 MeV. Most of the gamma-ray lines that are expected to be used for planetary gamma-ray spectroscopy were found in the recorded spectra and the principal lines in these spectra are presented. 58 refs., 7 figs., 9 tabs.

  16. A tetrahedron-based endmember selection approach for urban impervious surface mapping.

    PubMed

    Wang, Wei; Yao, Xinfeng; Zhai, Junpeng; Ji, Minhe

    2014-01-01

    The pixel purity index (PPI) and two-dimensional (2-D) scatter plots are two popular techniques for endmember extraction in remote sensing spectral mixture analysis, yet both suffer from one major drawback, that is, the selection of a final set of endmembers has to endure a cumbersome process of iterative visual inspection and human intervention, especially when a spectrally-complex urban scene is involved. Within the conceptual framework of a V-H-L-S (vegetation-high albedo-low albedo-soil) model, which is expanded from the classic V-I-S (vegetation-impervious surface-soil) model, a tetrahedron-based endmember selection approach combined with a multi-objective optimization genetic algorithm (MOGA) was designed to identify urban endmembers from multispectral imagery. The tetrahedron defining the enclosing volume of MNF-transformed pixels in a three-dimensional (3-D) space was algorithmically sought, so that the tetrahedral vertices can ideally match the four components of the adopted model. A case study with Landsat Enhanced Thematic Mapper Plus (ETM+) satellite imagery in Shanghai, China was conducted to verify the validity of the method. The method performance was compared with those of the traditional PPI and 2-D scatter plots approaches. The results indicated that the tetrahedron-based endmember selection approach performed better in both accuracy and ease of identification for urban surface endmembers owing to the 3-D visualization analysis and use of the MOGA. PMID:24892938

  17. A Tetrahedron-Based Endmember Selection Approach for Urban Impervious Surface Mapping

    PubMed Central

    Wang, Wei; Yao, Xinfeng; Zhai, Junpeng; Ji, Minhe

    2014-01-01

    The pixel purity index (PPI) and two-dimensional (2-D) scatter plots are two popular techniques for endmember extraction in remote sensing spectral mixture analysis, yet both suffer from one major drawback, that is, the selection of a final set of endmembers has to endure a cumbersome process of iterative visual inspection and human intervention, especially when a spectrally-complex urban scene is involved. Within the conceptual framework of a V-H-L-S (vegetation-high albedo-low albedo-soil) model, which is expanded from the classic V-I-S (vegetation-impervious surface-soil) model, a tetrahedron-based endmember selection approach combined with a multi-objective optimization genetic algorithm (MOGA) was designed to identify urban endmembers from multispectral imagery. The tetrahedron defining the enclosing volume of MNF-transformed pixels in a three-dimensional (3-D) space was algorithmically sought, so that the tetrahedral vertices can ideally match the four components of the adopted model. A case study with Landsat Enhanced Thematic Mapper Plus (ETM+) satellite imagery in Shanghai, China was conducted to verify the validity of the method. The method performance was compared with those of the traditional PPI and 2-D scatter plots approaches. The results indicated that the tetrahedron-based endmember selection approach performed better in both accuracy and ease of identification for urban surface endmembers owing to the 3-D visualization analysis and use of the MOGA. PMID:24892938

  18. Simulation experiments for gamma-ray mapping of planetary surfaces: Scattering of high-energy neutrons

    NASA Technical Reports Server (NTRS)

    Brueckner, J.; Englert, P.; Reedy, R. C.; Waenke, H.

    1986-01-01

    The concentration and distribution of certain elements in surface layers of planetary objects specify constraints on models of their origin and evolution. This information can be obtained by means of remote sensing gamma-ray spectroscopy, as planned for a number of future space missions, i.e., Mars, Moon, asteroids, and comets. To investigate the gamma-rays made by interactions of neutrons with matter, thin targets of different composition were placed between a neutron-source and a high-resolution germanium spectrometer. Gamma-rays in the range of 0.1 to 8 MeV were accumulated. In one set of experiments a 14-MeV neutron generator using the T(d,n) reaction as neutron-source was placed in a small room. Scattering in surrounding walls produced a spectrum of neutron energies from 14 MeV down to thermal. This complex neutron-source induced mainly neutron-capture lines and only a few scattering lines. As a result of the set-up, there was a considerable background of discrete lines from surrounding materials. A similar situation exists under planetary exploration conditions: gamma-rays are induced in the planetary surface as well as in the spacecraft. To investigate the contribution of neutrons with higher energies, an experiment for the measurement of prompt gamma radiation was set up at the end of a beam-line of an isochronous cyclotron.

  19. Image system for three dimensional, 360 DEGREE, time sequence surface mapping of moving objects

    DOEpatents

    Lu, Shin-Yee

    1998-01-01

    A three-dimensional motion camera system comprises a light projector placed between two synchronous video cameras all focused on an object-of-interest. The light projector shines a sharp pattern of vertical lines (Ronchi ruling) on the object-of-interest that appear to be bent differently to each camera by virtue of the surface shape of the object-of-interest and the relative geometry of the cameras, light projector and object-of-interest Each video frame is captured in a computer memory and analyzed. Since the relative geometry is known and the system pre-calibrated, the unknown three-dimensional shape of the object-of-interest can be solved for by matching the intersections of the projected light lines with orthogonal epipolar lines corresponding to horizontal rows in the video camera frames. A surface reconstruction is made and displayed on a monitor screen. For 360.degree. all around coverage of theobject-of-interest, two additional sets of light projectors and corresponding cameras are distributed about 120.degree. apart from one another.

  20. Image system for three dimensional, 360{degree}, time sequence surface mapping of moving objects

    DOEpatents

    Lu, S.Y.

    1998-12-22

    A three-dimensional motion camera system comprises a light projector placed between two synchronous video cameras all focused on an object-of-interest. The light projector shines a sharp pattern of vertical lines (Ronchi ruling) on the object-of-interest that appear to be bent differently to each camera by virtue of the surface shape of the object-of-interest and the relative geometry of the cameras, light projector and object-of-interest. Each video frame is captured in a computer memory and analyzed. Since the relative geometry is known and the system pre-calibrated, the unknown three-dimensional shape of the object-of-interest can be solved for by matching the intersections of the projected light lines with orthogonal epipolar lines corresponding to horizontal rows in the video camera frames. A surface reconstruction is made and displayed on a monitor screen. For 360{degree} all around coverage of the object-of-interest, two additional sets of light projectors and corresponding cameras are distributed about 120{degree} apart from one another. 20 figs.

  1. Using Combined THEMIS Visible and Infrared Images to map Martian Topography and Slope- corrected Surface Thermal Properties

    NASA Astrophysics Data System (ADS)

    Cushing, G. E.; Titus, T. N.; Soderblom, L. A.; Kirk, R. L.

    2007-12-01

    Kirk et al. (2005) empirically deconvolved visible and thermal-infrared THEMIS data, isolating topographic information that produced an accurate digital-terrain model (DTM). Described here is the next step wherein we use the same dataset (Columbia Hills area, Mars) in conjunction with the KRC thermal model (Kieffer et al., 1977) to quantitatively derive and map slope-corrected thermophysical properties. Observed surface temperatures, at high spatial resolution, are a function of many variables such as: slope, albedo, thermal inertia, time, season and atmospheric opacity. We constrain each of these variables to construct a DTM and maps of slope-corrected albedo, slope/albedo-corrected thermal inertia, and surface temperatures across an entire scene for any time of day or year and any atmospheric opacity. DTMs greatly facilitate analyses of the Martian surface, but generating these data is a challenge. The MOLA global dataset does not have sufficient resolution (~3 km) to be combined with newer datasets (e.g. HiRISE, CTX, THEMIS, MOC, and CRISM), so new techniques to derive high-resolution DTMs are always being explored. Stereo imaging produces quality, high-resolution DTMs but is limited in the amount of available coverage. Photoclinometry techniques on visible-wavelength images have been widely investigated with varying degrees of success, but accounting for albedo variations across a scene has been an historical weakness of this method. Here we discuss a technique of combining THEMIS visible and thermal infrared (both daytime and nighttime) observations (Christensen et al., 2004) in such a manner that albedo variations in the scene are cancelled, allowing the production of a high-resolution DTM via photoclinometry techniques that are largely free of albedo-induced errors. We employ the KRC thermal-diffusion model to generate models of slope-corrected thermal properties from the resultant DTM and THEMIS observations. This technique can provide new perspectives and

  2. Mapping the environmental risk potential on surface water of pesticide contamination in the Prosecco's vineyard terraced landscape

    NASA Astrophysics Data System (ADS)

    Pizarro, Patricia; Ferrarese, Francesco; Loddo, Donato; Eugenio Pappalardo, Salvatore; Varotto, Mauro

    2016-04-01

    Intensive cropping systems today represent a paramount issue in terms of environmental impacts, since agricultural pollutants can constitute a potential threat to surface water, non-target organisms and aquatic ecosystems. Levels of pesticide concentrations in surface waters are indeed unquestionably correlated to crop and soil management practices at field-scale. Due to the numerous applications of pesticides required, orchards and vineyards can represent relevant non-point sources for pesticide contamination of water bodies, mainly prompted by soil erosion, surface runoff and spray drift. To reduce risks of pesticide contamination of surface water, the Directive 2009/128/CET imposed the local implementation of agricultural good practices and mitigation actions such as the use of vegetative buffer filter strips and hedgerows along river and pond banks. However, implementation of mitigation actions is often difficult, especially in extremely fragmented agricultural landscapes characterized by a complex territorial matrix set up on urban sprawling, frequent surface water bodies, important geomorphological processes and protected natural areas. Typically, such landscape matrix is well represented by the, Prosecco-DOCG vineyards area (NE of Italy, Province of Treviso) which lays on hogback hills of conglomerate, marls and sandstone that ranges between 50 and 500 m asl. Moreover such vineyards landscape is characterized by traditional and non-traditional agricultural terraces The general aim of this paper is to identify areas of surface water bodies with high potential risk of pesticide contamination from surrounding vineyards in the 735 ha of Lierza river basin (Refrontolo, TV), one of the most representative terraced landscape of the Prosecco-DOCG area. Specific aims are i) mapping terraced Prosecco-DOCG vineyards, ii) classifying potential risk from pesticide of the different areas. Remote sensing technologies such as four bands aerial photos (RGB+NIR) and Light

  3. Comparison of Digital Surface Models for Snow Depth Mapping with Uav and Aerial Cameras

    NASA Astrophysics Data System (ADS)

    Boesch, R.; Bühler, Y.; Marty, M.; Ginzler, C.

    2016-06-01

    Photogrammetric workflows for aerial images have improved over the last years in a typically black-box fashion. Most parameters for building dense point cloud are either excessive or not explained and often the progress between software releases is poorly documented. On the other hand, development of better camera sensors and positional accuracy of image acquisition is significant by comparing product specifications. This study shows, that hardware evolutions over the last years have a much stronger impact on height measurements than photogrammetric software releases. Snow height measurements with airborne sensors like the ADS100 and UAV-based DSLR cameras can achieve accuracies close to GSD * 2 in comparison with ground-based GNSS reference measurements. Using a custom notch filter on the UAV camera sensor during image acquisition does not yield better height accuracies. UAV based digital surface models are very robust. Different workflow parameter variations for ADS100 and UAV camera workflows seem to have only random effects.

  4. Mapping of surface activity on the W UMa-type system VW Cephei

    NASA Technical Reports Server (NTRS)

    Bradstreet, David H.; Guinan, Edward F.

    1988-01-01

    After multifilter photometry of the W UMa-type contact binary VW Cep (P = 6.67 hr; G5V + K0V) in 1986/87 revealed large asymmetries in the light curves believed to be caused by large, cool starspot regions on the surface of the larger stars, in Apr. 1987 it was observed with IUE to study the chromospheres and transition regions of the components. During one complete orbital cycle, three SWP and four LWP low dispersion spectra were obtained, including and then excluding the suspected active region. Phase dependent TR line emission strengths were found, most notably C IV, which is 50 percent stronger when the spot region is most visible. The results could be important because VW Cep represents an extreme case for studying stellar dynamo theory and observations can play a crucial role in the unterstanding of magnetic fields and activity cycles in rapidly rotating solar-like stars.

  5. Three-dimensional spin mapping of antiferromagnetic nanopyramids having spatially alternating surface anisotropy at room temperature.

    PubMed

    Wang, Kangkang; Smith, Arthur R

    2012-11-14

    Antiferromagnets play a key role in modern spintronic devices owing to their ability to modify the switching behavior of adjacent ferromagnets via the exchange bias effect. Consequently, detailed measurements of the spin structure at antiferromagnetic interfaces and surfaces are highly desirable, not only for advancing technologies but also for enabling new insights into the underlying physics. Here using spin-polarized scanning tunneling microscopy at room-temperature, we reveal in three-dimensions an orthogonal spin structure on antiferromagnetic compound nanopyramids. Contrary to expected uniaxial anisotropy based on bulk properties, the atomic terraces are found to have alternating in-plane and out-of-plane magnetic anisotropies. The observed layer-wise alternation in anisotropy could have strong influences on future nanoscale spintronic applications.

  6. Nanoscale chemical mapping using three-dimensional adiabatic compression of surface plasmon polaritons.

    PubMed

    De Angelis, Francesco; Das, Gobind; Candeloro, Patrizio; Patrini, Maddalena; Galli, Matteo; Bek, Alpan; Lazzarino, Marco; Maksymov, Ivan; Liberale, Carlo; Andreani, Lucio Claudio; Di Fabrizio, Enzo

    2010-01-01

    The fields of plasmonics, Raman spectroscopy and atomic force microscopy have recently undergone considerable development, but independently of one another. By combining these techniques, a range of complementary information could be simultaneously obtained at a single molecule level. Here, we report the design, fabrication and application of a photonic-plasmonic device that is fully compatible with atomic force microscopy and Raman spectroscopy. Our approach relies on the generation and localization of surface plasmon polaritons by means of adiabatic compression through a metallic tapered waveguide to create strongly enhanced Raman excitation in a region just a few nanometres across. The tapered waveguide can also be used as an atomic force microscope tip. Using the device, topographic, chemical and structural information about silicon nanocrystals may be obtained with a spatial resolution of 7 nm.

  7. Surface Current Density Mapping for Identification of Gastric Slow Wave Propagation

    PubMed Central

    Bradshaw, L. A.; Cheng, L. K.; Richards, W. O.; Pullan, A. J.

    2009-01-01

    The magnetogastrogram records clinically relevant parameters of the electrical slow wave of the stomach noninvasively. Besides slow wave frequency, gastric slow wave propagation velocity is a potentially useful clinical indicator of the state of health of gastric tissue, but it is a difficult parameter to determine from noninvasive bioelectric or biomagnetic measurements. We present a method for computing the surface current density (SCD) from multichannel magnetogastrogram recordings that allows computation of the propagation velocity of the gastric slow wave. A moving dipole source model with hypothetical as well as realistic biomagnetometer parameters demonstrates that while a relatively sparse array of magnetometer sensors is sufficient to compute a single average propagation velocity, more detailed information about spatial variations in propagation velocity requires higher density magnetometer arrays. Finally, the method is validated with simultaneous MGG and serosal EMG measurements in a porcine subject. PMID:19403355

  8. Chemical Schemes for Surface Modification of Icy Satellites: A Road Map

    NASA Technical Reports Server (NTRS)

    Delitsky, Mona L.; Lane, Arthur L.

    1997-01-01

    The icy Galilean satellites of Jupiter are subject to magnetospheric plasma ion bombardment, which induces chemical changes within the ice. The possible detection of CO2 on the surface of Ganymede by the Galileo spacecraft makes for a more complicated chemistry and increases the number of chemical compounds that may then be present. We outline chemical schemes for the irradiation of pure and mixed ices H2O/CO2 and suggest species which observers may detect on Europa, Ganymede, and Callisto, such as C3O2, H2CO3, H2O2, CO3, HO2, CO, H2CO, CH2CO, as well as K2O, KOH, and SO3, from plasma implantation. Column abundances of compounds in the ice are calculated using a specified energy input and G values (yield per 100 eV).

  9. Hydrogeology, groundwater levels, and generalized potentiometric-surface map of the Green River Basin lower Tertiary aquifer system, 2010–14, in the northern Green River structural basin

    USGS Publications Warehouse

    Bartos, Timothy T.; Hallberg, Laura L.; Miller, Cheryl E.

    2015-07-14

    The groundwater-level measurements were used to construct a generalized potentiometric-surface map of the Green River Basin lower Tertiary aquifer system. Groundwater-level altitudes measured in nonflowing and flowing wells used to construct the potentiometric-surface map ranged from 6,451 to 7,307 feet (excluding four unmeasured flowing wells used for contour construction purposes). The potentiometric-surface map indicates that groundwater in the study area generally moves from north to south, but this pattern of flow is altered locally by groundwater divides, groundwater discharge to the Green River, and possibly to a tributary river (Big Sandy River) and two reservoirs (Fontenelle and Big Sandy Reservoirs).

  10. Multi-Wavelength, Multi-Beam, and Polarization-Sensitive Laser Transmitter for Surface Mapping

    NASA Technical Reports Server (NTRS)

    Yu, Anthony W.; Ramos-Izquierdo, Luis; Harding, David; Huss, Tim

    2011-01-01

    A multi-beam, multi-color, polarized laser transmitter has been developed for mapping applications. It uses commercial off-the-shelf components for a lowcost approach for a ruggedized laser suitable for field deployment. The laser transmitter design is capable of delivering dual wavelengths, multiple beams on each wavelength with equal (or variable) intensities per beam, and a welldefined state of polarization. This laser transmitter has been flown on several airborne campaigns for the Slope Imaging Multi-Polarization Photon Counting Lidar (SIMPL) instrument, and at the time of this reporting is at a technology readiness level of between 5 and 6. The laser is a 1,064-nm microchip high-repetition-rate laser emitting energy of about 8 microjoules per pulse. The beam was frequency-doubled to 532 nm using a KTP (KTiOPO4) nonlinear crystal [other nonlinear crystals such as LBO (LiB3O5) or periodically poled lithium niobiate can be used as well, depending on the conversion efficiency requirements], and the conversion efficiency was approximately 30 percent. The KTP was under temperature control using a thermoelectric cooler and a feedback monitoring thermistor. The dual-wavelength beams were then spectrally separated and each color went through its own optical path, which consisted of a beam-shaping lens, quarterwave plate (QWP), and a birefringent crystal (in this case, a calcite crystal, but others such as vanadate can be used). The QWP and calcite crystal set was used to convert the laser beams from a linearly polarized state to circularly polarized light, which when injected into a calcite crystal, will spatially separate the circularly polarized light into the two linear polarized components. The spatial separation of the two linearly polarized components is determined by the length of the crystal. A second set of QWP and calcite then further separated the two beams into four. Additional sets of QWP and calcite can be used to further split the beams into multiple

  11. Neutron-induced gamma ray spectroscopy: Simulations for chemical mapping of planetary surfaces

    NASA Astrophysics Data System (ADS)

    Brückner, J.; Wänke, H.; Reedy, R. C.

    Cosmic rays interact with the surface of a planetary body and produce a cascade of secondary particles, such as neutrons. Neutron-induced scattering and capture reactions play an important role in the production of discrete gamma ray lines that can be measured by a gamma ray spectrometer on board an orbiting spacecraft. These data can be used to determine the concentration of many elements in the surface of a planetary body, which enables us to recognize individual geological units and provides clues to the bulk composition and in turn the origin and evolution of the body. To investigate the gamma ray fluxes induced by accelerator neutrons, experiments were carried out by irradiating thin targets with neutrons of energies from 14 MeV to 0.025 eV. The neutron fluxes at target position were measured by foil activation techniques. The ratio of the epithermal to thermal neutron flux was determined to be 2.0, a value that is similar to that in the moon. Gamma rays in the energy range of 0.1 to 8 MeV emitted by the targets and the surrounding material were measured by a high-resolution germanium detector. Most of the gamma ray lines that are expected to be used for planetary gamma ray Spectroscopy were found in the recorded spectra. These spectra were unfolded, background was subtracted, and gamma ray attenuation corrections were made to obtain the corresponding gamma ray fluxes from the targets. The majority of gamma ray lines were narrow without noticeable Doppler broadening except for the very broad 4.4-MeV line of carbon and five asymmetric germanium lines produced by the detector itself. The agreement of measured gamma ray flux ratios with calculated flux ratios for neutron-capture reactions showed that thermal neutron data can be used for theoretical calculations of low-energy neutron-induced gamma ray fluxes. This study was a first step toward a more realistic simulation of cosmic-ray-induced gamma-ray production and it indicates the importance of accelerator

  12. Neutron-induced gamma ray spectroscopy: Simulations for chemical mapping of planetary surfaces

    NASA Astrophysics Data System (ADS)

    Brückner, J.; Wänke, H.; Reedy, R. C.

    1987-09-01

    Cosmic rays interact with the surface of a planetary body and produce a cascade of secondary particles, such as neutrons. Neutron-induced scattering and capture reactions play an important role in the production of discrete gamma ray lines that can be measured by a gamma ray spectrometer on board an orbiting spacecraft. These data can be used to determine the concentration of many elements in the surface of a planetary body, which enables us to recognize individual geological units and provides clues to the bulk composition and in turn the origin and evolution of the body. To investigate the gamma ray fluxes induced by accelerator neutrons, experiments were carried out by irradiating thin targets with neutrons of energies from 14 MeV to 0.025 eV. The neutron fluxes at target position were measured by foil activation techniques. The ratio of the epithermal to thermal neutron flux was determined to be 2.0, a value that is similar to that in the moon. Gamma rays in the energy range of 0.1 to 8 MeV emitted by the targets and the surrounding material were measured by a high-resolution germanium detector. Most of the gamma ray lines that are expected to be used for planetary gamma ray spectroscopy were found in the recorded spectra. These spectra were unfolded, background was subtracted, and gamma ray attenuation corrections were made to obtain the corresponding gamma ray fluxes from the targets. The majority of gamma ray lines were narrow without noticeable Doppler broadening except for the very broad 4.4-MeV line of carbon and five asymmetric germanium lines produced by the detector itself. The agreement of measured gamma ray flux ratios with calculated flux ratios for neutron-capture reactions showed that thermal neutron data can be used for theoretical calculations of low-energy neutron-induced gamma ray fluxes. This study was a first step toward a more realistic simulation of cosmic-ray-induced gamma-ray production and it indicates the importance of accelerator

  13. High resolution synoptic salinity mapping to identify groundwater--surface water discharges in lowland rivers.

    PubMed

    Pai, Henry; Villamizar, Sandra R; Harmon, Thomas C

    2015-04-21

    Quantifying distributed lateral groundwater contributions to surface water (GW-SW discharges) is a key aspect of tracking nonpoint-source pollution (NPSP) within a watershed. In this study, we characterized distributed GW-SW discharges and associated salt loading using elevated GW specific conductance (SC) as a tracer along a 38 km reach of the Lower Merced River in Central California. High resolution longitudinal surveys for multiple flows (1.3-150 m(3) s(-1)) revealed river SC gradients that mainly decreased with increasing flow, suggesting a dilution effect and/or reduced GW-SW discharges due to hydraulic gradient reductions. However, exceptions occurred (gradients increasing with increasing flow), pointing to complex spatiotemporal influences on GW-SW dynamics. The surveys revealed detailed variability in salinity gradients, from which we estimated distributed GW-SW discharge and salt loading using a simple mixing model. Modeled cumulative GW discharges for two surveys unaffected by ungauged SW discharges were comparable in magnitude to differential gauging-based discharge estimates and prior GW-SW studies along the same river reach. Ungauged lateral inlets and sparse GW data limited the study, and argue for enhancing monitoring efforts. Our approach provides a rapid and economical method for characterizing NPSP for gaining rivers in the context of integrated watershed modeling and management.

  14. Temperature dependence of Fe/++/ crystal field spectra - Implications to mineralogical mapping of planetary surfaces

    NASA Technical Reports Server (NTRS)

    Sung, C.-M.; Singer, R. B.; Parkin, K. M.; Burns, R. G.; Osborne, M.

    1977-01-01

    Results are reported of Fe(++) crystal field spectral measurements for olivines and pyroxenes up to 400 C. The results are correlated with crystal structure data at elevated temperatures, and the validity of remote-sensed identifications of minerals on hot surfaces of the moon and Mercury is assessed. Two techniques were used to obtain spectra of minerals at elevated temperatures using a spectrophotometer. One employed a diamond cell assembly or a specially designed sample holder to measure polarized absorption spectra of heated single crystals. For the other technique, a sample holder was designed to attach to a diffuse reflectance accessory to produce reflectance spectra of heated powdered samples. Polarized absorption spectra of forsterite at 20-400 C are shown in a graph. Other graphs show the temperature dependence of Fe(++) crystal field bands in olivines, the diffuse reflectance spectra of olivine at 40-400 C, the polarization absorption spectra of orthopyroxene at 30-400 C, the diffuse reflectance spectra of pigeonite at 40-400 C, and unpolarized absorption spectra of lunar pyroxene from Apollo 15 rock 15058.

  15. Experimental Approach to Controllably Vary Protein Oxidation While Minimizing Electrode Adsorption for Boron-Doped Diamond Electrochemical Surface Mapping Applications

    SciTech Connect

    McClintock, Carlee; Hettich, Robert {Bob} L

    2013-01-01

    Oxidative protein surface mapping has become a powerful approach for measuring the solvent accessibility of folded protein structures. A variety of techniques exist for generating the key reagent hydroxyl radicals for these measurements; however, many of these approaches require use of radioactive sources or caustic oxidizing chemicals. The purpose of this research was to evaluate and optimize the use of boron-doped diamond (BDD) electrochemistry as a highly accessible tool for producing hydroxyl radicals as a means to induce a controllable level of oxidation on a range of intact proteins. These experiments utilize a relatively high flow rates to reduce protein residence time inside the electrochemical flow chamber, along with a unique cell activation approach to improve control over the intact protein oxidation yield. Studies were conducted to evaluate the level of protein adsorption onto the electrode surface. This report demonstrates a robust protocol for the use of BDD electrochemistry and high performance LC-MS/MS as a high-throughput experimental pipeline for probing higher order protein structure, and illustrates how it is complementary to predictive computational modeling efforts.

  16. Homology modelling of the major peanut allergen Ara h 2 and surface mapping of IgE-binding epitopes.

    PubMed

    Barre, Annick; Borges, Jean-Philippe; Culerrier, Raphaël; Rougé, Pierre

    2005-09-15

    Three-dimensional models built for the peanut Ara h 2 allergen and other structurally-related 2S albumin allergens of dietary nuts exhibited an overall three-dimensional fold stabilized by disulphide bridges well conserved among all the members of the 2S albumin superfamily. Conformational analysis of the linear IgE-binding epitopes mapped on the molecular surface of Ara h 2 showed no structural homology with the corresponding regions of the walnut Jug r 1, the pecan nut Car i 1 or the Brazil nut Ber e 1 allergens. The absence of epitopic community does not support the allergenic cross-reactivity observed between peanut and walnut or Brazil nut, which presumably depends on other ubiquitous seed storage protein allergens, namely the vicilins. However, the major IgE-binding epitope identified on the molecular surface of the walnut Jug r 1 allergen shared a pronounced structural homology with the corresponding region of the pecan nut Car i 1 allergen. With the exception of peanut, 2S albumins could thus account for the IgE-binding cross-reactivity observed between some other dietary nuts, e.g. walnut and pecan nut. PMID:15899521

  17. Axial Surface Mapping of Wrinkle Ridges on Solis Planum, Mars from MOLA Topography: Constraints on Subsurface Blind Thrust Geometry

    NASA Technical Reports Server (NTRS)

    Vidal, A.; Mueller, K.; Golombek, M. P.

    2003-01-01

    We undertook axial surface mapping of selected wrinkle ridges on Solis Planum, Mars in order to assess the subsurface geometry of blind thrusts proposed to exist beneath them. This work builds on previous work that defined structural families of wrinkle ridges based on their surface morphology in this region. Although a growing consensus exists for models of wrinkle ridge kinematics and mechanics, a number of current problems remain. These include the origin of topographic offset across the edges of wrinkle ridges, the relationship between broad arches and superposed ridges, the origin of smaller wrinkles, and perhaps most importantly, the trajectory of blind thrusts that underlie wrinkle ridges and accommodate shortening at deeper crustal levels. We are particularly interested in defining the depths at which blind thrusts flatten under wrinkle ridges in order to provide constraints on the brittle-ductile transition during Early Hesperian time. We also seek to test whether wrinkle ridges on Solis Planum develop above reactivated faults or newly formed ones.

  18. Systematic discovery of linear binding motifs targeting an ancient protein interaction surface on MAP kinases.

    PubMed

    Zeke, András; Bastys, Tomas; Alexa, Anita; Garai, Ágnes; Mészáros, Bálint; Kirsch, Klára; Dosztányi, Zsuzsanna; Kalinina, Olga V; Reményi, Attila

    2015-11-01

    Mitogen-activated protein kinases (MAPK) are broadly used regulators of cellular signaling. However, how these enzymes can be involved in such a broad spectrum of physiological functions is not understood. Systematic discovery of MAPK networks both experimentally and in silico has been hindered because MAPKs bind to other proteins with low affinity and mostly in less-characterized disordered regions. We used a structurally consistent model on kinase-docking motif interactions to facilitate the discovery of short functional sites in the structurally flexible and functionally under-explored part of the human proteome and applied experimental tools specifically tailored to detect low-affinity protein-protein interactions for their validation in vitro and in cell-based assays. The combined computational and experimental approach enabled the identification of many novel MAPK-docking motifs that were elusive for other large-scale protein-protein interaction screens. The analysis produced an extensive list of independently evolved linear binding motifs from a functionally diverse set of proteins. These all target, with characteristic binding specificity, an ancient protein interaction surface on evolutionarily related but physiologically clearly distinct three MAPKs (JNK, ERK, and p38). This inventory of human protein kinase binding sites was compared with that of other organisms to examine how kinase-mediated partnerships evolved over time. The analysis suggests that most human MAPK-binding motifs are surprisingly new evolutionarily inventions and newly found links highlight (previously hidden) roles of MAPKs. We propose that short MAPK-binding stretches are created in disordered protein segments through a variety of ways and they represent a major resource for ancient signaling enzymes to acquire new regulatory roles. PMID:26538579

  19. Mapping sub-surface geostrophic currents from altimetry and a fleet of gliders

    NASA Astrophysics Data System (ADS)

    Alvarez, A.; Chiggiato, J.; Schroeder, K.

    2013-04-01

    Integrating the observations gathered by different platforms into a unique physical picture of the environment is a fundamental aspect of networked ocean observing systems. These are constituted by a spatially distributed set of sensors and platforms that simultaneously monitor a given ocean region. Remote sensing from satellites is an integral part of present ocean observing systems. Due to their autonomy, mobility and controllability, underwater gliders are envisioned to play a significant role in the development of networked ocean observatories. Exploiting synergism between remote sensing and underwater gliders is expected to result on a better characterization of the marine environment than using these observational sources individually. This study investigates a methodology to estimate the three dimensional distribution of geostrophic currents resulting from merging satellite altimetry and in situ samples gathered by a fleet of Slocum gliders. Specifically, the approach computes the volumetric or three dimensional distribution of absolute dynamic height (ADH) that minimizes the total energy of the system while being close to in situ observations and matching the absolute dynamic topography (ADT) observed from satellite at the sea surface. A three dimensional finite element technique is employed to solve the minimization problem. The methodology is validated making use of the dataset collected during the field experiment called Rapid Environmental Picture-2010 (REP-10) carried out by the NATO Undersea Research Center-NURC during August 2010. A marine region off-shore La Spezia (northwest coast of Italy) was sampled by a fleet of three coastal Slocum gliders. Results indicate that the geostrophic current field estimated from gliders and altimetry significantly improves the estimates obtained using only the data gathered by the glider fleet.

  20. Mapping intertidal surface sediment type distribution with retrieved sedimental components using EO-1 Hyperion data

    NASA Astrophysics Data System (ADS)

    Li, Huan; Zhang, Dong; Zhang, Ying; Xu, Yong

    2010-11-01

    Sediment type was one of the most important parameters of intertidal zone. The hydrodynamics and morphological changes could be indicated by sediment types very well, and the understanding of their distribution and stability could provide an important insight into littoral marine ecology. The way of conventional survey for sediment types was expensive and time-consuming. The objective of this study was to develop a method to distinguish sediment types using remote sensing, and enable which to be an alternative to traditional methods. Intertidal zone sediments were sampled at the south of Dafeng port, Yancheng city, Jiangsu province, China. Samples were collected from the upper 3cm surface of intertidal zone. The laboratory spectral reflectance data were obtained using a spectrometer. Particle-size of sediment samples were measured by Mastersizer 2000. Through analyzing characteristics of spectral reflectance for sediment samples, we found that two bands were sensitive to content of sediment components (sand, silt and clay) with central wavelengths at 864 and 1034 nm. However, the position of sensitive bands changed as moisture varied. In order to eliminate the impact of moisture on sediment spectral reflectance, moisture was introduced as a crucial factor to build regression equations with reflectance of sensitive bands to get contents of different sediment components, and then Shepard classification system was applied to acquire spatial distribution of sediment types. This way provided a quick, non-destructive and nonpolluting survey method. Meanwhile, this intelligent way of extracting information from muddy coastal zone will contribute to constructing digital earth, the huge system which benefits human beings.

  1. Mapping intertidal surface sediment type distribution with retrieved sedimental components using EO-1 Hyperion data

    NASA Astrophysics Data System (ADS)

    Li, Huan; Zhang, Dong; Zhang, Ying; Xu, Yong

    2009-09-01

    Sediment type was one of the most important parameters of intertidal zone. The hydrodynamics and morphological changes could be indicated by sediment types very well, and the understanding of their distribution and stability could provide an important insight into littoral marine ecology. The way of conventional survey for sediment types was expensive and time-consuming. The objective of this study was to develop a method to distinguish sediment types using remote sensing, and enable which to be an alternative to traditional methods. Intertidal zone sediments were sampled at the south of Dafeng port, Yancheng city, Jiangsu province, China. Samples were collected from the upper 3cm surface of intertidal zone. The laboratory spectral reflectance data were obtained using a spectrometer. Particle-size of sediment samples were measured by Mastersizer 2000. Through analyzing characteristics of spectral reflectance for sediment samples, we found that two bands were sensitive to content of sediment components (sand, silt and clay) with central wavelengths at 864 and 1034 nm. However, the position of sensitive bands changed as moisture varied. In order to eliminate the impact of moisture on sediment spectral reflectance, moisture was introduced as a crucial factor to build regression equations with reflectance of sensitive bands to get contents of different sediment components, and then Shepard classification system was applied to acquire spatial distribution of sediment types. This way provided a quick, non-destructive and nonpolluting survey method. Meanwhile, this intelligent way of extracting information from muddy coastal zone will contribute to constructing digital earth, the huge system which benefits human beings.

  2. Overcoming key technological challenges in using mass spectrometry for mapping cell surfaces in tissues.

    PubMed

    Griffin, Noelle M; Schnitzer, Jan E

    2011-02-01

    Plasma membranes form a critical biological interface between the inside of every cell and its external environment. Their roles in multiple key cellular functions make them important drug targets. However the protein composition of plasma membranes in general is poorly defined as the inherent properties of lipid embedded proteins, such as their hydrophobicity, low abundance, poor solubility and resistance to digestion and extraction makes them difficult to isolate, solubilize, and identify on a large scale by traditional mass spectrometry methods. Here we describe some of the significant advances that have occurred over the past ten years to address these challenges including: i) the development of new and improved membrane isolation techniques via either subfractionation or direct labeling and isolation of plasma membranes from cells and tissues; ii) modification of mass spectrometry methods to adapt to the hydrophobic nature of membrane proteins and peptides; iii) improvements to digestion protocols to compensate for the shortage of trypsin cleavage sites in lipid-embedded proteins, particularly multi-spanning proteins, and iv) the development of numerous bioinformatics tools which allow not only the identification and quantification of proteins, but also the prediction of membrane protein topology, membrane post-translational modifications and subcellular localization. This review emphasis the importance and difficulty of defining cells in proper patho- and physiological context to maintain the in vivo reality. We focus on how key technological challenges associated with the isolation and identification of cell surface proteins in tissues using mass spectrometry are being addressed in order to identify and quantify a comprehensive plasma membrane for drug and target discovery efforts.

  3. High-resolution topography along surface rupture of the 16 October 1999 Hector Mine, California (Mw 7.1) from airborne laser swath mapping

    USGS Publications Warehouse

    Hudnutt, K.W.; Borsa, A.; Glennie, C.; Minster, J.-B.

    2002-01-01

    In order to document surface rupture associated with the Hector Mine earthquake, in particular, the area of maximum slip and the deformed surface of Lavic Lake playa, we acquired high-resolution data using relatively new topographic-mapping methods. We performed a raster-laser scan of the main surface breaks along the entire rupture zone, as well as along an unruptured portion of the Bullion fault. The image of the ground surface produced by this method is highly detailed, comparable to that obtained when geologists make particularly detailed site maps for geomorphic or paleoseismic studies. In this case, however, for the first time after a surface-rupturing earthquake, the detailed mapping is along the entire fault zone rather than being confined to selected sites. These data are geodetically referenced, using the Global Positioning System, thus enabling more accurate mapping of the rupture traces. In addition, digital photographs taken along the same flight lines can be overlaid onto the precise topographic data, improving terrain visualization. We demonstrate the potential of these techniques for measuring fault-slip vectors.

  4. A data centred method to estimate and map changes in the full distribution of daily surface temperature

    NASA Astrophysics Data System (ADS)

    Chapman, Sandra; Stainforth, David; Watkins, Nicholas

    2016-04-01

    Characterizing how our climate is changing includes local information which can inform adaptation planning decisions. This requires quantifying the geographical patterns in changes at specific quantiles or thresholds in distributions of variables such as daily surface temperature. Here we focus on these local changes and on a model independent method to transform daily observations into patterns of local climate change. Our method [1] is a simple mathematical deconstruction of how the difference between two observations from two different time periods can be assigned to the combination of natural statistical variability and/or the consequences of secular climate change. This deconstruction facilitates an assessment of how fast different quantiles of the distributions are changing. This involves both determining which quantiles and geographical locations show the greatest change but also, those at which any change is highly uncertain. For temperature, changes in the distribution itself can yield robust results [2]. We demonstrate how the fundamental timescales of anthropogenic climate change limit the identification of societally relevant aspects of changes. We show that it is nevertheless possible to extract, solely from observations, some confident quantified assessments of change at certain thresholds and locations [3]. We demonstrate this approach using E-OBS gridded data [4] timeseries of local daily surface temperature from specific locations across Europe over the last 60 years. [1] Chapman, S. C., D. A. Stainforth, N. W. Watkins, On estimating long term local climate trends, Phil. Trans. Royal Soc., A,371 20120287 (2013) [2] Stainforth, D. A. S. C. Chapman, N. W. Watkins, Mapping climate change in European temperature distributions, ERL 8, 034031 (2013) [3] Chapman, S. C., Stainforth, D. A., Watkins, N. W. Limits to the quantification of local climate change, ERL 10, 094018 (2015) [4] Haylock M. R. et al ., A European daily high-resolution gridded dataset of

  5. Bladder dose-surface maps and urinary toxicity: Robustness with respect to motion in assessing local dose effects.

    PubMed

    Palorini, F; Botti, A; Carillo, V; Gianolini, S; Improta, I; Iotti, C; Rancati, T; Cozzarini, C; Fiorino, C

    2016-03-01

    The purpose of this study was to quantify the impact of inter-fraction modifications of bladder during RT of prostate cancer on bladder dose surface maps (DSM). Eighteen patients treated with daily image-guided Tomotherapy and moderate hypofractionation (70-72.8Gy at 2.5-2.6Gy/fr in 28 fractions and full bladder) were considered. Bladder contours were delineated on co-registered daily Megavoltage CT (MVCT) by a single observer and copied on the planning CT to generate dose-volume/surface histograms (DVH/DSH) and bladder DSMs. Discrepancies between planned and daily absorbed doses were analyzed through the average of individual systematic errors, the population systematic errors and the population random errors for the DVH/DSHs and DSMs. In total, 477 DVH/DSH and 472 DSM were available. DSH and DVH showed small population systematic errors of absolute surfaces (<3.4cm(2)) and volumes (<8.4cm(3)) at the highest doses. The dose to the posterior bladder base assessed on DSMs showed a mean systematic error below 1Gy, with population systematic and random errors within 4 and 3Gy, respectively. The region surrounding this area shows higher mean systematic errors (1-3Gy), population systematic (8-11Gy) and random (5-7Gy) errors. In conclusion, DVH/DSH and DSMs are quite stable with respect to inter-fraction variations in the high-dose region, within about 2cm from bladder base. Larger systematic variations occur in the anterior portion and cranially 2.5-3.5cm from the base. Results suggest that dose predictors related to the high dose area (including the trigone dose) are likely to be sufficiently reliable with respect to the expected variations due to variable bladder filling.

  6. Evaluation of a moderate resolution, satellite-based impervious surface map using an independent, high-resolution validation data set

    USGS Publications Warehouse

    Jones, J.W.; Jarnagin, T.

    2009-01-01

    Given the relatively high cost of mapping impervious surfaces at regional scales, substantial effort is being expended in the development of moderate-resolution, satellite-based methods for estimating impervious surface area (ISA). To rigorously assess the accuracy of these data products high quality, independently derived validation data are needed. High-resolution data were collected across a gradient of development within the Mid-Atlantic region to assess the accuracy of National Land Cover Data (NLCD) Landsat-based ISA estimates. Absolute error (satellite predicted area - "reference area") and relative error [satellite (predicted area - "reference area")/ "reference area"] were calculated for each of 240 sample regions that are each more than 15 Landsat pixels on a side. The ability to compile and examine ancillary data in a geographic information system environment provided for evaluation of both validation and NLCD data and afforded efficient exploration of observed errors. In a minority of cases, errors could be explained by temporal discontinuities between the date of satellite image capture and validation source data in rapidly changing places. In others, errors were created by vegetation cover over impervious surfaces and by other factors that bias the satellite processing algorithms. On average in the Mid-Atlantic region, the NLCD product underestimates ISA by approximately 5%. While the error range varies between 2 and 8%, this underestimation occurs regardless of development intensity. Through such analyses the errors, strengths, and weaknesses of particular satellite products can be explored to suggest appropriate uses for regional, satellite-based data in rapidly developing areas of environmental significance. ?? 2009 ASCE.

  7. Surface Map Traffic Intent Displays and Net-Centric Data-link Communications for NextGen

    NASA Technical Reports Server (NTRS)

    Shelton, Kevin J.; Prinzel, Lawrence J., III; Jones, Denise R.; Allamandola, Angela S.; Arthur, Jarvis J., III; Bailey, Randall E.

    2009-01-01

    By 2025, U.S. air traffic is predicted to increase three fold and may strain the current air traffic management system, which may not be able to accommodate this growth. In response to this challenge, a revolutionary new concept has been proposed for U.S. aviation operations, termed the Next Generation Air Transportation System or "NextGen". Many key capabilities are being identified to enable NextGen, including the use of data-link communications. Because NextGen represents a radically different approach to air traffic management and requires a dramatic shift in the tasks, roles, and responsibilities for the flight deck, there are numerous research issues and challenges that must be overcome to ensure a safe, sustainable air transportation system. Flight deck display and crew-vehicle interaction concepts are being developed that proactively investigate and overcome potential technology and safety barriers that might otherwise constrain the full realization of NextGen. The paper describes simulation research, conducted at National Aeronautics and Space Administration (NASA) Langley Research Center, examining data-link communications and traffic intent data during envisioned four-dimensional trajectory (4DT)-based and equivalent visual (EV) surface operations. Overall, the results suggest that controller pilot data-link communications (CPDLC) with the use of mandatory pilot read-back of all clearances significantly enhanced situation awareness for 4DT and EV surface operations. The depiction of graphical traffic state and intent information on the surface map display further enhanced off-nominal detection and pilot qualitative reports of safety and awareness.

  8. Wildfire Risk Mapping over the State of Mississippi: Land Surface Modeling Approach

    SciTech Connect

    Cooke, William H.; Mostovoy, Georgy; Anantharaj, Valentine G; Jolly, W. Matt

    2012-01-01

    Three fire risk indexes based on soil moisture estimates were applied to simulate wildfire probability over the southern part of Mississippi using the logistic regression approach. The fire indexes were retrieved from: (1) accumulated difference between daily precipitation and potential evapotranspiration (P-E); (2) top 10 cm soil moisture content simulated by the Mosaic land surface model; and (3) the Keetch-Byram drought index (KBDI). The P-E, KBDI, and soil moisture based indexes were estimated from gridded atmospheric and Mosaic-simulated soil moisture data available from the North American Land Data Assimilation System (NLDAS-2). Normalized deviations of these indexes from the 31-year mean (1980-2010) were fitted into the logistic regression model describing probability of wildfires occurrence as a function of the fire index. It was assumed that such normalization provides more robust and adequate description of temporal dynamics of soil moisture anomalies than the original (not normalized) set of indexes. The logistic model parameters were evaluated for 0.25 x0.25 latitude/longitude cells and for probability representing at least one fire event occurred during 5 consecutive days. A 23-year (1986-2008) forest fires record was used. Two periods were selected and examined (January mid June and mid September December). The application of the logistic model provides an overall good agreement between empirical/observed and model-fitted fire probabilities over the study area during both seasons. The fire risk indexes based on the top 10 cm soil moisture and KBDI have the largest impact on the wildfire odds (increasing it by almost 2 times in response to each unit change of the corresponding fire risk index during January mid June period and by nearly 1.5 times during mid September-December) observed over 0.25 x0.25 cells located along the state of Mississippi Coast line. This result suggests a rather strong control of fire risk indexes on fire occurrence probability

  9. Body surface potential maps with low-level exercise in isolated left anterior descending coronary artery disease

    SciTech Connect

    Montague, T.J.; Johnstone, D.E.; Spencer, C.A.; Miller, R.M.; Mackenzie, B.R.; Gardner, M.J.; Horacek, B.M.

    1988-02-01

    One hundred and twenty-lead body surface potential maps (BSPMs) were recorded at rest, at immediate cessation of exercise and after 1 (early) and 5 minutes (late) of recovery in 14 patients with isolated, critical, left anterior descending (LAD) coronary artery stenosis. Exercise endpoints, at an average peak rate of 98 +/- 13, were usual pain worsening in 13 LAD patients, and diagnostic ST depression in lead V5 in 1 patient. Twelve patients also had positive thallium scans. BSPMs were also recorded in 8 normal subjects who exercised to peak heart rates similar to those of the LAD subjects. Spatially, there were similar exercise changes in QRS and ST-segment integral patterns over the precordium and inferior torso in both groups. These were transient in the control group but persisted to late recovery in the LAD group, particularly for ST integral. Quantitatively, multivariate analysis revealed significant temporal differences between the 2 groups. However, the only independent BSPM variable was the sum of ST integral decrease, averaging --2323 +/- 1809 microV.s for normal patients between rest and immediate cessation of exercise, compared with -3828 +/- 2329 microV.s for the LAD patients. Late recovery minus rest difference averaged -1264 +/- 1080 microV.s for normal subjects and -2575 +/- 1844 microV.s for LAD patients. To control for the physiologic changes of exercise, the ST integral temporal differential maps of the normal subjects were subtracted from those of the LAD patients and the sum of negative intergroup differences was assumed to reflect only ischemia. Correlation of ST integral ischemia values at immediate cessation of exercise and late recovery was high; however, intertechnique correlations of the BSPM variables with quantitative angiographic scores and thallium perfusion scan scores revealed generally low r values (range 0 to 0.52).

  10. Characterizing and Mapping Ice Sheet Surface Topography Using a Medium-Footprint, Multi- Beam, Waveform-Recording Lidar

    NASA Astrophysics Data System (ADS)

    Hofton, M. A.; Blair, J. B.; Rabine, D. L.; Luthcke, S. B.

    2007-12-01

    Lidar surveys of the Greenland ice sheet have been used to study mass-balance changes since the early 1990's. Sensors include NASA's ATM system (e.g., Krabill et al., 2000), and the ICESat (Schutz et al., 2002), a large- footprint, spaceborne system launched in 2003 for monitoring long-term trends in ice mass balance. To complement these data sets and prepare for the next-generation of spaceborne measurements, the Laser Vegetation Imaging Sensor (LVIS) was flown onboard the NASA P-3 aircraft over Greenland in September 2007. LVIS is an airborne, medium- footprint (25m diameter), full waveform-recording, airborne, scanning lidar system that has been used extensively for mapping forest structure, habitat, carbon and natural hazards. The system digitally records the shape of the returning laser echo, or waveform, after its interaction with the various reflecting surfaces of the earth, providing a true 3-dimensional record of the surface structure. Data collected included ground elevation and vertical extent measurements for each laser footprint, as well as the vertical distribution of intercepted surfaces (the return waveform) from which surface slope, roughness and other metrics can be extracted. During the mission, data were collected along ICESat repeat ground-track "corridors" that encompass a variety of terrain types (e.g., inland ice, crevasses, ponds, sastrugi, ice/rock margins, and bare earth), over sea- ice in northern Greenland, and at Jakobshavn Isbrae, a fast-flowing outlet glacier where discharge rates have increased in recent years. Data from this mission will be used to assess the ability of 25m-footprint, waveform lidar to precisely and accurately characterize and monitor the surface of the Greenland ice sheet and its margins. The data will also be used to assess the effects of across-track slope corrections currently being used on the ICESat data. The study will highlight the complimentary measurement science that can be achieved using a multi

  11. The application of remotely sensed data to pedologic and geomorphic mapping on alluvial fan and playa surfaces in Saline Valley, California

    NASA Technical Reports Server (NTRS)

    Miller, D. A.; Petersen, G. W.; Kahle, A. B.

    1986-01-01

    Arid and semiarid regions yield excellent opportunities for the study of pedologic and geomorphic processes. The dominance of rock and soil exposure over vegetation not only provides the ground observer with observational possibilities but also affords good opportunities for measurement by aircraft and satellite remote sensor devices. Previous studies conducted in the area of pedologic and geomorphic mapping in arid regions with remotely sensed data have utilized information obtained in the visible to near-infrared portion of the spectrum. Thermal Infrared Multispectral Scanner (TIMS) and Thematic Mapping (TM) data collected in 1984 are being used in comjunction with maps compiled during a Bureau of Land Management (BLM) soil survey to aid in a detailed mapping of alluvial fan and playa surfaces within the valley. The results from this study may yield valuable information concerning the application of thermal data and thermal/visible data combinations to the problem of dating pedologic and geomorphic features in arid regions.

  12. Potentiometric surface and water-level difference maps of selected confined aquifers in Southern Maryland and Maryland’s Eastern Shore, 1975-2013

    USGS Publications Warehouse

    Staley, Andrew W.; Andreasen, David C.; Curtin, Stephen E.

    2014-01-01

    The potentiometric surface maps show water levels ranging from 165 feet above sea level to 199 feet below sea level. Water levels have declined by as much as 113 feet in the Aquia aquifer since 1982, 81 feet in the Magothy aquifer since 1975, and 61 and 95 feet in the Upper Patapsco and Lower Patapsco aquifer systems, respectively, since 1990.

  13. Mapping the low-surface brightness Universe in the UV band with Lyα emission from IGM filaments

    NASA Astrophysics Data System (ADS)

    Silva, Marta B.; Kooistra, Robin; Zaroubi, Saleem

    2016-10-01

    A large fraction of the baryonic matter in the Universe is located in filaments in the intergalactic medium (IGM). However, the low surface brightness of these filaments has not yet allowed their direct detection except in very special regions in the circum-galactic medium. Here we simulate the intensity and spatial fluctuations in Lyman alpha (Lyα) emission from filaments in the IGM and discuss the prospects for the next generation of space-based instruments to detect the low-surface brightness Universe at ultraviolet (UV) wavelengths. Starting with a high-resolution N-body simulation, we obtain the dark matter density fluctuations and associate baryons with the dark matter particles assuming that they follow the same spatial distribution. The IGM thermal and ionization state is set by a model of the UV background and by the relevant cooling processes for a hydrogen and helium gas. The Lyα emissivity is then estimated, taking into account recombination and collisional excitation processes. We find that the detection of these filaments through their Lyα emission is well in the reach of the next generation of UV space-based instruments and so it should be achieved in the next decade. The density field is populated with halos and galaxies and their Lyα emission is estimated. Galaxies are treated as foregrounds and so we discuss methods to reduce their contamination from observational maps. Finally, we estimate the UV continuum background as a function of the redshift of the Lyα emission line and discuss how this continuum can affect observations.

  14. Road-Mapping the Way Forward for Sentinel-3 STM SAR-Mode Waveform Retracking over Water Surfaces

    NASA Astrophysics Data System (ADS)

    Benveniste, Jérôme; Cotton, David; Dinardo, Salvatore; Lucas, Bruno Manuel; Martin-Puig, Cristina; Ray, Chris; Clarizia, Maria Paola; Gommenginger, Christine

    2013-04-01

    In the framework of the preparation activities for the Sentinel-3 Topography Mission, ESA launched an R&D project on SAR Altimetry and Applications over Ocean, Coastal zones and Inland waters. The main objective was to design a novel processing algorithm over ocean surface that would run in the Sentinel-3 ground segment to provide unprecedented quality altimeter measurements over ocean surfaces when in SAR mode. Also coastal zones and inland waters were the targets of research to derive new models and re-trackers for these difficult measurements. Innovative physically based models have been developed for near-nadir ocean altimetric waveforms in SAR-Mode and subsequently implemented in prototype ocean SAR re-trackers to perform the validation. A Detailed Processing Model Document was delivered for implementation in the Sentinel-3 Topography Mission Ground Segment. In this paper, we present the approach used to date within SAMOSA and the heritage behind the latest SAMOSA2 model. The SAMOSA2 model offers a complete description of SAR altimeter echoes from ocean surfaces, expressed in the form of maps of reflected power in delay and Doppler space. SAMOSA2 is able to account for an elliptical antenna pattern, mispointing errors in roll and yaw, errors in range cell migration correction, surface scattering pattern, non-linear ocean wave statistics and spherical Earth surface effects. SAMOSA2 addresses some of the known limitations of the earlier SAMOSA1 model, in particular with regards to sensitivity to mispointing. Due to its truly comprehensive character, the full SAMOSA2 model is a complicated semi-analytical formulation that still relies on some numerical integrations. The need for numerical integrations significantly impacts the computation time and raises problems of numerical stability once implemented operationally in a re-tracker scheme. This has potentially serious implications that could prevent the implementation of SAMOSA2 in operational re-tracker schemes

  15. Ligand mapping on protein surfaces by the 3D-RISM theory: toward computational fragment-based drug design.

    PubMed

    Imai, Takashi; Oda, Koji; Kovalenko, Andriy; Hirata, Fumio; Kidera, Akinori

    2009-09-01

    In line with the recent development of fragment-based drug design, a new computational method for mapping of small ligand molecules on protein surfaces is proposed. The method uses three-dimensional (3D) spatial distribution functions of the atomic sites of the ligand calculated using the molecular theory of solvation, known as the 3D reference interaction site model (3D-RISM) theory, to identify the most probable binding modes of ligand molecules. The 3D-RISM-based method is applied to the binding of several small organic molecules to thermolysin, in order to show its efficiency and accuracy in detecting binding sites. The results demonstrate that our method can reproduce the major binding modes found by X-ray crystallographic studies with sufficient precision. Moreover, the method can successfully identify some binding modes associated with a known inhibitor, which could not be detected by X-ray analysis. The dependence of ligand-binding modes on the ligand concentration, which essentially cannot be treated with other existing computational methods, is also investigated. The results indicate that some binding modes are readily affected by the ligand concentration, whereas others are not significantly altered. In the former case, it is the subtle balance in the binding affinity between the ligand and water that determines the dominant ligand-binding mode.

  16. Effective extraction of diagnostic ECG waveform information using orthonormal basis functions derived from body surface potential maps.

    PubMed

    Kornreich, F; Rautaharju, P M; Warren, J W; Horacek, B M; Dramaix, M

    1985-10-01

    A common basis of orthogonal waveform functions was derived from 128 lead body surface potential maps of 405 subjects. Twelve such orthogonal functions or frames were adequate for reconstruction of original ECGs from the beginning of QRS to the end of T. A larger number of frames (18) was required when basis functions were derived separately for QRS (10) and ST-T segments (8). Diagnostic information content of the coefficients of the orthogonal basis functions was evaluated in comparison with Minnesota Code criteria for myocardial infarction and with a more advanced multivariate ECG analysis program (Pipberger Program). This was done by deriving a linear discriminant function for separating normals from ECGs of patients with myocardial infarction and testing the discriminant in a different test population of infarcts and normals. The diagnostic accuracy of orthogonal basis functions was as good as that of Pipberger's program and considerably better than that of the Minnesota Code. The classification method described is insensitive to noise and errors in detecting QRS and T wave onsets and offsets or in selecting proper baseline for amplitude measurements. The robustness and enhanced classification stability with respect to noise and minor wave detection errors is a potential advantage particularly in serial ECG comparison.

  17. Mapping Quaternary Alluvial Fans in the Southwestern United States based on Multi-Parameter Surface Roughness of LiDAR Topographic Data

    NASA Astrophysics Data System (ADS)

    Regmi, N. R.; McDonald, E.; Bacon, S. N.

    2012-12-01

    Quaternary alluvial fans, common landforms in hyper- to semi-arid regions, have diverse surface morphology, desert varnish accumulation, clasts rubification, desert pavement formation, soil development, and soil stratigraphy. Their age and surface topographic expression vary greatly within a single fan between adjacent fans. Numerous studies have demonstrated that the su