Science.gov

Sample records for level high resolution

  1. Historical high-resolution dynamic sea level variations

    NASA Astrophysics Data System (ADS)

    Brunnabend, Sandra-Esther; Dijkstra, Henk A.; Kliphuis, Michael; van Werkhoven, Ben; Bal, Henri E.; Maassen, Jason; van Meersbergen, Maarten; Seinstra, Frank

    2014-05-01

    To investigate future changes in the dynamics of the ocean and therefore in dynamic sea level, ocean models need to be able to adequately represent oceanic dynamical processes. Therefore, resolving ocean eddies and representing boundary currents is of major importance. In this study, we investigate historical variations in dynamical sea surface height using the strongly eddying global version of the Parallel Ocean Program (POP). First, differences in high and low-resolution ocean model results (0.1 vs. 1.0 degree) were analyzed using a climatological atmospheric forcing dataset. Second, we forced the high-resolution model by atmospheric conditions over the period from 1950 to 2000 that are derived from a simulation using the ECHAM5-OM1 model (within the ESSENCE project, see www.knmi.nl/~sterl/Essence/). In general, the large-scale ocean fields of the POP model simulation agree well with those of the low-resolution ocean model (MPI-OM) results. Variations occur due to the different models used and, especially, due to the capability of the high-resolution POP model to resolve eddies. A comparison of high-resolution ocean model results with in-situ measurements, such as dynamic topography provided by altimetry, and salinity and temperature provided by the WOA2013, also show good agreement.

  2. A high resolution water level forecast for the German Bight

    NASA Astrophysics Data System (ADS)

    Niehüser, Sebastian; Dangendorf, Sönke; Arns, Arne; Jensen, Jürgen

    2016-04-01

    Many coastal regions worldwide are potentially endangered by storm surges which can cause disastrous damages and loss of life. Due to climate change induced sea level rise, an accumulation of such events is expected by the end of the 21th century. Therefore, advanced storm surge warnings are needed to be prepared when another storm surge hits the coast. In the shallow southeastern North Sea these storm surge warnings are nowadays routinely provided for selected tide gauge locations along a coastline through state-of-the-art forecast systems, which are based on a coupled system of empirical tidal predictions and numerical storm surge forecasts. Along the German North Sea coastline, the Federal Maritime and Hydrographic Agency in cooperation with the German Weather Service is responsible for the storm surge warnings. They provide accurate, high frequency and real-time water level forecasts for up to six days ahead at selected tide gauge sites via internet, telephone and broadcast. Since water levels along the German North Sea coastline are dominated by shallow water effects and a very complex bathymetric structure of the seabed, the pointwise forecast is not necessarily transferable to un-gauged areas between the tide gauges. Here we aim to close this existing gap and develop water level forecasts with a high spatial (continuously with a resolution of at least 1 kilometer) as well as a high temporal (at least 15-minute values) resolution along the entire German North Sea coastline. We introduce a new methodology for water level forecasts which combines empirical or statistical and numerical models. While the tidal forecast is performed by non-parametric interpolation techniques between un-gauged and gauged sites, storm surges are estimated on the basis of statistical/empirical storm surge formulas taken from a numerical model hindcast. The procedure will be implemented in the operational mode forced with numerical weather forecasts.

  3. Modeling future high-resolution dynamic sea level change

    NASA Astrophysics Data System (ADS)

    Brunnabend, Sandra-Esther; Dijkstra, Henk A.; Kliphuis, Michael A.; van Werkhoven, Ben; Bal, Henri E.; van Meersbergen, Maarten; Seinstra, Frank; Maassen, Jason

    2015-04-01

    Different studies have shown that resolving ocean eddies and representing boundary currents are of major importance when simulating changes in dynamic sea level on regional scale. Therefore, we use the strongly eddying global model version of the Parallel Ocean Program to simulate high-resolution future (up to the year 2100) sea surface height variations (SSH) under the SRES-A1B atmospheric forcing scenario. Results show dynamic sea level changes in the Southern Ocean that are caused by the southward shift in the westerly winds. The warming ocean (global mean sea surface temperature rises by about 2°C over the period 2000-2100) leads to a strong reduction of the Atlantic Meridional Overturning Circulation (AMOC). The magnitude of this reduction is affected by a feedback involving the heat transport to the sub-polar gyre region and evaporation over the North Atlantic region. The ocean circulation changes cause regional deviations from global mean sea level change in the North Atlantic. At coastal regions of eastern North America, dynamic sea level change leads to a positive deviation from global mean sea level change in the order of several decimeters. In the sub-polar gyre region a negative deviation from global mean sea level occurs. In the western North Atlantic, not only mean regional sea level is changed but also its variability, caused by shifted eddy pathways. This leads to a change in the frequency distribution of SSH anomalies, which has important consequences for regional sea level extremes.

  4. A high-resolution time-to-digital converter using a three-level resolution

    NASA Astrophysics Data System (ADS)

    Dehghani, Asma; Saneei, Mohsen; Mahani, Ali

    2016-08-01

    In this article, a three-level resolution Vernier delay line time-to-digital converter (TDC) was proposed. The proposed TDC core was based on the pseudo-differential digital architecture that made it insensitive to nMOS and pMOS transistor mismatches. It also employed a Vernier delay line (VDL) in conjunction with an asynchronous read-out circuitry. The time interval resolution was equal to the difference of delay between buffers of upper and lower chains. Then, via the extra chain included in the lower delay line, resolution was controlled and power consumption was reduced. This method led to high resolution and low power consumption. The measurement results of TDC showed a resolution of 4.5 ps, 12-bit output dynamic range, and integral nonlinearity of 1.5 least significant bits. This TDC achieved the consumption of 68.43 µW from 1.1-V supply.

  5. High resolution geodetic techniques for monitoring fluid levels over time

    NASA Astrophysics Data System (ADS)

    Hare, Jennifer Thompson

    1998-11-01

    In the first study, a novel surveillance technique is developed in which surface gravity observations are used to monitor the progress of a gas cap waterflood in the 8200 ft (2500 m) deep Prudhoe Bay reservoir, Alaska. This cost-effective method requires that high-precision gravity surveys be repeated every 3 to 5 years. Differences in the gravity field with time reflect changes in the reservoir fluid density distribution. A preliminary field test at Prudhoe Bay indicates survey accuracy of 5 to 10 mu Gal can be achieved for gravity data using a modified Lacoste & Romberg "G" type meter or Scintrex CG-3M combined with Global Positioning System (GPS) positioning. Forward gravity modeling of a suite of reservoir simulations of the proposed waterflood predicts variation in surface measurements of 100 mu Gal after 5 years of injection, and 180 to 250 mu Gal after 15 years. A constrained, least-squares method is used to invert synthetic gravity data for subsurface density distributions. The modeling procedure has been formulated to allow testing of the models for sensitivity to gravity sampling patterns, noise characteristics, and various constraints on model parameters such as density range, total mass, and model moment of inertia. Horizontal feature resolution of the waterflood is about 5000 ft (1520 m) for constrained inverse models from synthetic gravity with 5 mu Gal standard deviation noise. Results of the modeling indicate that inversion of time-lapse gravity data is a viable and promising technique for monitoring reservoir gas cap waterfloods. In the second study, the problem of how to estimate ancient lake levels from the geomorphology of remnant shoreline terraces is investigated. High resolution, GPS controlled, topographic data from around the highstand shoreline of Pleistocene Lake Lahontan in western Nevada provide the means for isolating coherent terrace features which are related to the paleoshoreline level. Determination of an unambiguous point or

  6. High illumination resolution test of low-light-level image intensifier

    NASA Astrophysics Data System (ADS)

    Bai, Xiaofeng; Yin, Lei; Zhu, Yufeng; He, Yingping; Miao, Zhuang; Hu, Wen; Hou, Zhipeng; Shi, Hongli

    2013-08-01

    High illumination resolution, which directly determines the applied characteristic of night vision system in flashlight or high light level condition, is an important performance parameter for evaluating the characteristic of low light level image intensifier used in high light level condition. In this article, according to the limited resolution test technique, the test principle, test condition and test method to high illumination resolution are described in detail associated with operation mode and protective way of low light level image intensifier. Test system for measuring the high illumination resolution has been founded based on the limited resolution test system. The value of high illumination for measuring the high illumination resolution has been calculated in theory and measured by illuminometer. High illumination resolution of low light level image intensifiers have been measured in test system, results show that high illumination resolution test system is satisfied the need for measuring high illumination resolution of low light level image intensifier, and test system output light illumination must be greater than 1×103 lux. Light of high illumination, which can be correctly measured by illuminometer, is transferred legitimately. That is worthwhile to evaluate the operational characteristic of low light level image intensifier.

  7. Exploiting Aura OMI Level 2 Data with High Resolution Visualization

    NASA Astrophysics Data System (ADS)

    Wei, J. C.; Yang, W.; Johnson, J. E.; Zhao, P.; Gerasimov, I. V.; Pham, L.; Vicente, G. A.; Shen, S.

    2014-12-01

    Satellite data products are important for a wide variety of applications that can bring far-reaching benefits to the science community and the broader society. These benefits can best be achieved if the satellite data are well utilized and interpreted, such as model inputs from satellite, or extreme event (such as volcano eruption, dust storm, …etc) interpretation from satellite. Unfortunately, this is not always the case, despite the abundance and relative maturity of numerous satellite data products provided by NASA and other organizations. One way to help users better understand the satellite data is to provide data along with 'Images', including accurate pixel-level (Level 2) information, pixel coverage area delineation, and science team recommended quality screening for individual geophysical parameters. Goddard Earth Sciences Data and Information Services Center (GES DISC) always strives to best support (i.e., Software-as-a-service, SaaS) the user-community for NASA Earth Science Data. In this case, we will present a new visualization tool that helps users exploiting Aura Ozone Monitoring Instrument (OMI) Level 2 data. This new visualization service utilizes Open Geospatial Consortium (OGC) standard-compliant Web Mapping Service (WMS) and Web Coverage Service (WCS) calls in the backend infrastructure. The functionality of the service allows users to select data sources (e.g., multiple parameters under the same measurement, like NO2 and SO2 from OMI Level 2 or same parameter with different methods of aggregation, like NO2 in OMNO2G and OMNO2D products), defining area-of-interest and temporal extents, zooming, panning, overlaying, sliding, and data subsetting and reformatting. The interface will also be able to connect to other OGC WMS and WCS servers, which will greatly enhance its expandability to integrate additional outside data/map sources (such as Global Imagery Browse Services (GIBS)).

  8. Pores and ridges: high-resolution fingerprint matching using level 3 features.

    PubMed

    Jain, Anil K; Chen, Yi; Demirkus, Meltem

    2007-01-01

    Fingerprint friction ridge details are generally described in a hierarchical order at three different levels, namely, Level 1 (pattern), Level 2 (minutia points), and Level 3 (pores and ridge contours). Although latent print examiners frequently take advantage of Level 3 features to assist in identification, Automated Fingerprint Identification Systems (AFIS) currently rely only on Level 1 and Level 2 features. In fact, the Federal Bureau of Investigation's (FBI) standard of fingerprint resolution for AFIS is 500 pixels per inch (ppi), which is inadequate for capturing Level 3 features, such as pores. With the advances in fingerprint sensing technology, many sensors are now equipped with dual resolution (500 ppi/1,000 ppi) scanning capability. However, increasing the scan resolution alone does not necessarily provide any performance improvement in fingerprint matching, unless an extended feature set is utilized. As a result, a systematic study to determine how much performance gain one can achieve by introducing Level 3 features in AFIS is highly desired. We propose a hierarchical matching system that utilizes features at all the three levels extracted from 1,000 ppi fingerprint scans. Level 3 features, including pores and ridge contours, are automatically extracted using Gabor filters and wavelet transform and are locally matched using the Iterative Closest Point (ICP) algorithm. Our experiments show that Level 3 features carry significant discriminatory information. There is a relative reduction of 20 percent in the equal error rate (EER) of the matching system when Level 3 features are employed in combination with Level 1 and 2 features. This significant performance gain is consistently observed across various quality fingerprint images. PMID:17108380

  9. Multi-temporal, high spatial resolution water level monitoring of the Everglades

    NASA Astrophysics Data System (ADS)

    Hong, S.; Wdowinski, S.; Kim, S.

    2008-05-01

    Water level information in South Florida's Everglades is very important for understanding the hydrology of this fragile ecosystem. Currently water levels are determined by a dense stage (water level) network providing high spatial resolution observation. However, because there are a finite number of stage stations in Everglades, water levels in areas located between stage stations can only be estimated by interpolation. Space-borne Interferometric Synthetic Aperture Radar (InSAR) techniques were successfully used to detect high spatial resolution (20-50 meter pixel resolution) water level changes in the Everglades and other wetlands. However, the InSAR observations are relative, providing measure of water level changes (not absolute). In this study we presents a new InSAR technique which enables to estimate a time series of absolute water levels using radar observations acquired successively over the Everglades. In this preliminary stage, we limit our study to Water Conservation Area 1 (WCA1), which is a managed area located in the northern section of the Everglades. The main advantage of the new technique is the reconstruction of absolute water level information instead of previous approaches calculating only relative water level changes. The new technique is called Small Temporal Baseline Subset (STBAS), which utilizes highly coherent interferometric phases obtained only with relatively short time difference between two SAR acquisitions (e.g. 24 or 48 recurrence periods in Radarsat-1 SAR system). The observed interferometric observations have to be calibrated with ground truth data as the reference wetland sheet flow vary daily. We use daily stage data measured at 13 stage stations in WCA1 to calibrate the space-based observations. This information is integrated using the Singular Value Decomposition (SVD) method to generate a time series of absolute water levels. Our calibration-validation study shows a very good fit to the stage data. The correlation

  10. High resolution reconstruction of relative sea-level on the Outer Banks, North Carolina

    NASA Astrophysics Data System (ADS)

    Kemp, A. C.; Horton, B. P.; Reide, C. D.; Stephen, C. J.; Feyen, J. C.; Thomson, K.

    2006-12-01

    The need for high resolution sea-level reconstruction has increased drastically with the realization that global warming may accelerate the rate of sea-level rise, resulting in increased coastal flooding. Determining the physical response of a coastline to sea-level rise is one of the most important problems to be addressed in applied coastal geology today. This concern is particularly acute for the Outer Banks and its back barrier estuary system which are considered by the United States Geological Survey (USGS) as having a "very high" vulnerability to sea-level rise. In order to consider the potential impacts sea-level rise may have on the Outer Banks it is necessary to place them in an appropriate geological framework. Scenarios for future sea-level rise are concerned with decadal to centennial timescales; as such they must be viewed in light of geologically derived sea level reconstructions at a comparable temporal resolution. The microfossil based transfer function approach is a quantitative methodology which can be effective in establishing these kind of records. We provide a high resolution relative sea-level history for the Outer Banks, North Carolina in the absence of a local, reliable tide gauge of sufficient, continuous duration. Contemporary foraminifera were collected from five back barrier marshes on the Outer Banks to create a regional scale modern training set. The use of multiple marshes from a region increases the ecological and environmental diversity included within the training set and reduces the probability of a no modern analogue outcome. In order to merge the five spatially distinct sites and to relate each to local tide levels we the VDatum transformation tool. This method relates all contemporary samples to a common orthometric datum (NAVD88) and reduces error associated with the implicit assumption that the hydrodynamic regime at a locality is the same as that which prevails at the nearest tide gauge. A transfer function was developed to

  11. Analysis of Ultra High Resolution Sea Surface Temperature Level 4 Datasets

    NASA Technical Reports Server (NTRS)

    Wagner, Grant

    2011-01-01

    Sea surface temperature (SST) studies are often focused on improving accuracy, or understanding and quantifying uncertainties in the measurement, as SST is a leading indicator of climate change and represents the longest time series of any ocean variable observed from space. Over the past several decades SST has been studied with the use of satellite data. This allows a larger area to be studied with much more frequent measurements being taken than direct measurements collected aboard ship or buoys. The Group for High Resolution Sea Surface Temperature (GHRSST) is an international project that distributes satellite derived sea surface temperatures (SST) data from multiple platforms and sensors. The goal of the project is to distribute these SSTs for operational uses such as ocean model assimilation and decision support applications, as well as support fundamental SST research and climate studies. Examples of near real time applications include hurricane and fisheries studies and numerical weather forecasting. The JPL group has produced a new 1 km daily global Level 4 SST product, the Multiscale Ultrahigh Resolution (MUR), that blends SST data from 3 distinct NASA radiometers: the Moderate Resolution Imaging Spectroradiometer (MODIS), the Advanced Very High Resolution Radiometer (AVHRR), and the Advanced Microwave Scanning Radiometer ? Earth Observing System(AMSRE). This new product requires further validation and accuracy assessment, especially in coastal regions.We examined the accuracy of the new MUR SST product by comparing the high resolution version and a lower resolution version that has been smoothed to 19 km (but still gridded to 1 km). Both versions were compared to the same data set of in situ buoy temperature measurements with a focus on study regions of the oceans surrounding North and Central America as well as two smaller regions around the Gulf Stream and California coast. Ocean fronts exhibit high temperature gradients (Roden, 1976), and thus

  12. Multi-Level Building Reconstruction for Automatic Enhancement of High Resolution Dsms

    NASA Astrophysics Data System (ADS)

    Arefi, H.; Reinartz, P.

    2012-07-01

    In this article a multi-level approach is proposed for reconstruction-based improvement of high resolution Digital Surface Models (DSMs). The concept of Levels of Detail (LOD) defined by CityGML standard has been considered as basis for abstraction levels of building roof structures. Here, the LOD1 and LOD2 which are related to prismatic and parametric roof shapes are reconstructed. Besides proposing a new approach for automatic LOD1 and LOD2 generation from high resolution DSMs, the algorithm contains two generalization levels namely horizontal and vertical. Both generalization levels are applied to prismatic model of buildings. The horizontal generalization allows controlling the approximation level of building footprints which is similar to cartographic generalization concept of the urban maps. In vertical generalization, the prismatic model is formed using an individual building height and continuous to included all flat structures locating in different height levels. The concept of LOD1 generation is based on approximation of the building footprints into rectangular or non-rectangular polygons. For a rectangular building containing one main orientation a method based on Minimum Bounding Rectangle (MBR) in employed. In contrast, a Combined Minimum Bounding Rectangle (CMBR) approach is proposed for regularization of non-rectilinear polygons, i.e. buildings without perpendicular edge directions. Both MBRand CMBR-based approaches are iteratively employed on building segments to reduce the original building footprints to a minimum number of nodes with maximum similarity to original shapes. A model driven approach based on the analysis of the 3D points of DSMs in a 2D projection plane is proposed for LOD2 generation. Accordingly, a building block is divided into smaller parts according to the direction and number of existing ridge lines. The 3D model is derived for each building part and finally, a complete parametric model is formed by merging all the 3D models of

  13. Alkyl-terminated Si(111) surfaces: A high-resolution, core level photoelectron spectroscopy study

    SciTech Connect

    Terry, J.; Linford, M.R.; Wigren, C.; Cao, R.; Pianetta, P.; Chidsey, C.E.

    1999-01-01

    The bonding of alkyl monolayers to Si(111) surfaces has been studied with high-resolution core level photoelectron spectroscopy (PES). Two very different wet-chemical methods have been used to prepare the alkyl monolayers: (i) Olefin insertion into the H{endash}Si bond of the H{endash}Si(111) surface, and (ii) replacement of Cl on the Cl{endash}Si(111) surface by an alkyl group from an alkyllithium reagent. In both cases, PES has revealed a C 1s component shifted to lower binding energy and a Si 2p component shifted to higher binding energy. Both components are attributed to the presence of a C{endash}Si bond at the interface. Along with photoelectron diffraction data [Appl. Phys. Lett. {bold 71}, 1056, (1997)], these data are used to show that these two synthetic methods can be used to functionalize the Si(111) surface. {copyright} {ital 1999 American Institute of Physics.}

  14. Background contamination by coplanar polychlorinated biphenyls (PCBs) in trace level high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) analytical procedures

    NASA Technical Reports Server (NTRS)

    Ferrario, J.; Byrne, C.; Dupuy, A. E. Jr

    1997-01-01

    The addition of the "dioxin-like" polychlorinated biphenyl (PCB) congeners to the assessment of risk associated with the 2,3,7,8-chlorine substituted dioxins and furans has dramatically increased the number of laboratories worldwide that are developing analytical procedures for their detection and quantitation. Most of these procedures are based on established sample preparation and analytical techniques employing high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS), which are used for the analyses of dioxin/furans at low parts-per-trillion (ppt) levels. A significant and widespread problem that arises when using these sample preparation procedures for the analysis of coplanar PCBs is the presence of background levels of these congeners. Industrial processes, urban incineration, leaking electrical transformers, hazardous waste accidents, and improper waste disposal practices have released appreciable quantities of PCBs into the environment. This contamination has resulted in the global distribution of these compounds via the atmosphere and their ubiquitous presence in ambient air. The background presence of these compounds in method blanks must be addressed when determining the exact concentrations of these and other congeners in environmental samples. In this study reliable procedures were developed to accurately define these background levels and assess their variability over the course of the study. The background subtraction procedures developed and employed increase the probability that the values reported accurately represent the concentrations found in the samples and were not biased due to this background contamination.

  15. High-resolution core-level photoemission study of dense Pb overlayers on Si(111)

    NASA Astrophysics Data System (ADS)

    Choi, Won Hoon; Kim, Keun Su; Yeom, Han Woong

    2008-11-01

    Structure and bonding configuration of dense Pb overlayers on the Si(111) surface have been studied by low-energy-electron diffraction and high-resolution photoelectron spectroscopy using synchrotron radiation. Several representative phases in its devil’s staircase phase diagram have been systematically investigated by varying the Pb coverage at 200-300 K. Pb5d photoelectron spectra indicate that there exist two distinct bonding configurations of Pb, which are interpreted as the hollow and on-top (T1) sites of the structure models proposed earlier. In case of surface Si atoms, mainly two different bonding environments are revealed by surface Si2p components for the low-density 7×3 phase. These can be assigned to T1 and modified on-top (T1') sites surrounding hollow-site adatoms. As the coverage increases, the minority site T1 converts to T1' making the topmost Si layer have a unique bonding configuration. This behavior is also consistent with the structure models. The temperature-dependent study reveals that the 7×3 phase undergoes a reversible phase transition into a 1×1 phase. This phase transition induces no significant change in Pb core levels but a marginal increase in the Si2p component for the T1' sites. We suggest a plausible scenario of the phase transition based on the structure model with 1.2 monolayer Pb and the active diffusion of hollow-site adatoms.

  16. Accuracy levels of land cover classified maps derived from mid and high spatial resolution remote sensing data

    NASA Astrophysics Data System (ADS)

    Brown, Bonnie J.

    This dissertation compares the accuracy of results of classifying data from mid-level to very high spatial resolutions (Landsat ETM+, SPOT 4, ASTER, SPOT 5, and QuickBird). Data from all of these sensors were classified for both urban and rural settings. The dissertation also examines accuracy levels between spectral and radiometric resolutions. Finally, it investigates the role that shadow plays in affecting accuracy levels from higher spatial resolution satellites. To compare as to whether there were significant differences in the accuracy levels between different sensors, each map's accuracy percentages were analyzed using Z-scores and kappa as described in the methodology section. QuickBird, with the highest spatial resolution, performed significantly more poorly in terms of providing accurate classification than any other sensor with respect to the rural environment. It also was significantly worse than Landsat ETM+ in providing accurate classification in the urban environment. In order to control for radiometric resolution, the 11-bit QuickBird data were converted to 8-bit data since QuickBird is the only sensor that does not have the same radiometric resolution. The resulting classification accuracy percentages were no better than that of random chance. When testing for accuracy in classification using only the three bands common to all sensors (green, red, and near-infrared) the result was there was essentially no difference between any of the sensors. This outcome supports the hypothesis that spectral resolution plays an important role in land cover accuracy. Using simple linear regression, the relationship between the percentage of shadow pixels and spatial resolution is examined. There is a moderate relationship between the spatial resolution of sensors and the percentages of shadow pixels where sensors with higher spatial resolution have a higher percentage of shadow pixels. These results agreed with literature from other studies in similar environments.

  17. High spatial resolution water level time series in the Florida Everglades wetlands using multi-track ALOS PALSAR data

    NASA Astrophysics Data System (ADS)

    Hong, S.; Wdowinski, S.

    2013-05-01

    Wetland InSAR (Interferometric Synthetic Aperture Radar) observations provide very high-resolution maps of water level changes that cannot be obtained by any terrestrial technique. We recently developed the Small Temporal Baseline Subset (STBAS) approach, which combines single-track InSAR and stage (water level) observations to generate high-resolution absolute water level time series maps. However, the temporal resolution of produced time series is coarse compared with in-situ stage observation and, hence, the usefulness of these maps is rather limited. To compensate for the low temporal resolution weakness of space-based water level time series, we propose using a multi-track STBAS technique, which utilizes all available Synthetic Aperture Radar (SAR) observations acquired over a certain wetland area. We use a four-year long L-band ALOS PALSAR dataset acquired during 2007-2011 to test the proposed method over the Water Conservation Area 1 (WCA1) in the Everglades wetlands, south Florida (USA). A total of 37 images acquired with four tracks were collected. Daily water level data at 12 stage stations, which are monitored by the Everglades Depth Estimation Network (EDEN) in WCA1 area, were used to calibrate the InSAR-derived water level data. The proposed multi-track approach yielded a significant improvement of temporal resolution, which is dependent on the SAR satellite revisit cycle. Instead of the 46-day repeat orbit of ALOS, the multi-track method produces water level maps with temporal resolution of only 7 days. A quality control analysis of the methods indicates that the average root mean square error (RMSE) of the differences between stage water level and retrieved water level by InSAR technique is 4.0 cm. The end products of absolute water level time series with improved temporal and very high spatial resolutions can be used as excellent constraints for high-resolution wetland flow models. Furthermore, the next generation of SAR satellites has been designed

  18. Importance of High-Resolution LiDAR Data in Modeling Runoff Levels Over Impervious Surfaces

    NASA Astrophysics Data System (ADS)

    Melosh, C.; Rao, M.

    2013-12-01

    Directly connected impervious areas collect and deliver unfiltered runoff to modified and impacted waterways. Modeling water flow over the landscape is an effective method of observing drainage patterns and predicting pollutant and sediment loadings. Improved models applying high-resolution elevation data can identify key areas with high pollutant output. This is a crucial issue in the Lake Tahoe Basin where lakeshore urban development has increased and lake clarity has been declining for years. This study aims to evaluate an integrated LiDAR and GIS-based modeling approach that uses a fine-scaled ground surface and impervious surface connectivity to predict the pollutant load in the Lake Tahoe Basin This study produced a fine-scaled surface model of nine subset catchments in the South Tahoe basin, including areas of low (below 20%), medium (30% to 50%) and high (above 50%) impervious surface cover. Our method integrated LiDAR, multispectral imagery, and GIS data to develop accurate terrain models, hydrologic routing, and directly connected impervious area layers for the Lake Tahoe basin. The high-density ground and object elevation data collected using Light Detection and Ranging (LiDAR) creates an accurate picture of water flow over the land, and obstacles to the flow such as buildings. High-resolution LiDAR data was obtained from the Round 10 Lake Tahoe Southern Nevada Public Land Management capital program from the year 2010. This data was processed to create a digital elevation model of the ground surface. Land use classification used object height information from the LiDAR cloud, NAIP 4-band images with 1-meter resolution and a normalized difference vegetation index image derived from the NAIP imagery. The US Army Core of Engineers hydrologic modeling system (HEC-HMS) will be used to model runoff. Based on long-term simulations the effect of directly connected impervious area on rainfall-runoff characteristics for the South Lake Tahoe catchments will be

  19. High resolution MR microscopy

    NASA Astrophysics Data System (ADS)

    Ciobanu, Luisa

    Magnetic resonance imaging (MRI) microscopy [1] has the potential to bring the full capabilities of NMR to arbitrarily specified localized positions within small samples. The most interesting target of study is the living biological cell, with typical dimensions ˜100 mum, but with substructures that are much smaller, such as the cell nucleus (typically ˜10 mu m) and mitochondria (1--10 mum). One anticipates that the development of MR microscopy with resolution at the level of these substructures or better and with a wide, three dimensional field-of-view could open a new avenue of investigation into the biology of the living cell. Although the first MR image of a single biological cell was reported in 1987 [2], the cell imaged had quite large (˜1 mm diameter) spatial dimensions and the resolution obtained (on the order of 10 mu m) was not adequate for meaningful imaging of more typically sized cells. The quest for higher resolution has continued. In 1989 Zhou et al. [3] obtained fully three dimensional images with spatial resolution of (6.37 mum)3, or 260 femtoliters. While better "in-plane" resolutions (i.e., the resolution in 2 of the 3 spatial dimensions) have since been obtained, [4, 5] this volume resolution was not exceeded until quite recently by Lee et al., [6] who report 2D images having volume resolution of 75 mum 3 and in-plane resolution of 1 mum. In parallel with these advances in raw resolution several investigators [7, 8, 9] have focused on localized spectroscopy and/or chemical shift imaging. The key obstacles to overcome in MR microscopy are (1) the loss of signal to noise that occurs when observing small volumes and (2) molecular diffusion during the measurement or encoding. To date the problem of sensitivity has typically been addressed by employing small micro-coil receivers. [10] The problem of molecular diffusion can only be defeated with strong magnetic field gradients that can encode spatial information quickly. We report MR microscopy

  20. Evaluation of Rock Mass Responses Using High Resolution Water-level Tiltmeter Arrays

    NASA Astrophysics Data System (ADS)

    Roberts, J. S.; Wang, H. F.; Fratta, D.; Stetler, L. D.; Volk, J. T.; Geox^Tm

    2010-12-01

    External forces act on the surface of the earth and produce deformation across all spatial and temporal scales. This research study focuses on the deformation evaluation of the rock-mass subjected to tidal, earthquake and surface forces. The events are monitored over horizontal distances of over 100 meters with tilt measurement arrays with a resolution of 10-8 radians. These measurements are obtained from hydrostatic leveling system (HLS) arrays that have been installed in the LaFarge mine in North Aurora, IL by Fermilab. Each sensor in the array is equipped with a water-filled reservoir beneath a capacitor. The amount of water in the reservoir is calculated as a function of the measured capacitance. Individual sensors are connected in a closed system via a water and air line. As the host rock expands and contracts sensors are raised relative to another and water is displaced. The water level in each reservoir is sent to a computer in the mine and recorded. In order to measure the tilt of the rock between two points, the difference in water levels between adjacent sensors is computed. The difference between the end sensors is also calculated to determine the larger-scale tilt of the array. The tiltmeters in LaFarge mine are supported by concrete pedestals installed on the floor of the drift. In the Homestake mine the tiltmeters are placed on similar pedestals, as well as platforms made of artificial wood decking. These platforms are fixed to the wall of the drift with a rock bolt. Time and frequency domain analyses were performed on time series ranging from hours to six months to capture relevant time scales including the response to the 2010 Chile Earthquake (hour-long scale), the stages of the moon (month scale), Fox River floods (flooding week long scales and pressure dissipation month-long scales). By monitoring tiltmeter array responses to different forces, we aim at making predictions about the material properties of rock masses.

  1. High-resolution tri-level process by downstream-microwave rf-biased etching

    NASA Astrophysics Data System (ADS)

    Rangelow, Ivo W.

    1991-03-01

    In this paper we discuss some properties of a novel dry etching system for high resolution transfer of e-beam generated pattern for a viable submicron lithography. In order to achieve pattern transfer by an e-beam lithography a tn-layer system has been used. The submicron pattern which has been generated in a 300 nm PBS-layer (imaging layer) was transfered into a 300 nm anorganic intermediate layer (Si3N4) by RIE with a CHF3-plasma. The underlayer of 1 micron polyimid was etched in a microwave downstream RF-biased etching system developed by Plasma Technology Ltd (UK). E-beam lithography generated structures of 75 nm size with very low image size bias were etched in Si3N4. After patterning in the polyimid layer structures with very high aspect ratio (10) could be achieved. It was observed that anisotropy is enhanced by crack-products that originate from the microwave downstream oxygen plasma and the CHF3+CH4 mixture in the space between the parallel-plate electrodes.

  2. Hydrological modeling using high resolution dem to level control on highways

    NASA Astrophysics Data System (ADS)

    Akbulut, Zeynep; Cömert, Çetin

    2016-04-01

    Floods are natural disasters that must be managed, controlled and taken precautions before it happens considering the damage they inflicted to environment and human lives. As to highways, the main vein of urban life flow, must be taken into consideration as a different entity that affected by excessive rainfalls and floods. Due to inadequate drainage that allow rainfall to form water ponds on highways cause vehicles to lose control and that lead vehicles to have traffic accidents. To reduce the traffic accidents caused by ponding waters on highways we need to know area of inundation and water depths. In this context we used FLO-2D Basic Model (2009) to hydrological modeling of Black Sea Coastal Highway with meteorological and hydrological data using a Digital Elevation Model (DEM). In this study, ponding areas on highways determined by simulating the rainfall with a high resolution DEM that can represent the actual road surface correctly. With this information, General Directorate of Highways (GDH) in Turkey can adjust the cross-sectional and longitudinal slope or build better and bigger drainage structures where water accumulated to prevent ponding. With the results obtained from Hydrological Model, GDH can rapidly control highways conformity to regulations before highways come into service. Also these ponding areas acquired by reveals where to prioritize in flood risk managements. Key Words: Area of Inundation, Digital Elevation Model, FLO-2D, Hydrological Modeling, Highway, Rainfall-Runoff Simulation, Water Depth.

  3. Very high spatial resolution optical and radar imagery in tracking water level fluctuations of a small inland reservoir

    NASA Astrophysics Data System (ADS)

    Simon, R. N.; Tormos, T.; Danis, P.-A.

    2015-06-01

    Tracking water level fluctuations in small lakes and reservoirs is important in order to better understand and manage these ecosystems. A geographic object-based image analysis (GEOBIA) method using very high spatial and temporal resolution optical (Pléiades) and radar (COSMO-SkyMed and TerraSAR-X) remote sensing imagery is presented here which (1) tracks water level fluctuations via variations in water surface area and (2) avoids common difficulties found in using single-band radar images for water-land image classification. Results are robust, with over 98% of image surface area correctly classified into land or water, R2 = 0.963 and RMSE = 0.42 m for a total water level fluctuation range of 5.94 m. Multispectral optical imagery is found to be more straightforward in producing results than single-band radar imagery, but the latter crucially increase temporal resolution to the point where fluctuations can be satisfactorily tracked in time. Moreover, an analysis suggests that high and medium spatial resolution imagery is sufficient, in at least some cases, in tracking the water level fluctuations of small inland reservoirs. Finally, limitations of the methodology presented here are briefly discussed along with potential solutions to overcome them.

  4. New Release of DUACS Products: 20 Years of High Resolution Sea Level Time Series Reprocessed

    NASA Astrophysics Data System (ADS)

    Pujol, Marie-Isabelle; Faugere, Yannice; Ssalto/Duacs Team; Bronner, Emilie; Picot, Nicolas

    2014-05-01

    During the last 20 years, altimeter high quality near real time and delayed time Level3 (along-track cross-calibrated SLA) and Level4 products (merging multiple sensors) were developed in parallel with Level2 (a.k.a [O/I]GDR) processing improvements. Directly usable and easier to manipulate, L3/4 products are vastly used and contribute to various studies in different fields, from climate and meteorological phenomena, to geophysics and biology. In early 2014, mainy changes will be implemented in the products. We present here the main changes and their impact for the users. A full reprocessing of the 20 years of altimeter data is on going, taking advantage of new missions, improved L2 processing, and a better understanding of the ocean stemming. An important improvement will be the use of a new reference period, taking into account the 20 years of altimeter data now available. This will lead to more pertinent sea level anomalies, without impact on the absolute topography. Validation results show improvements at climatic scales as well as mesoscales. The full reprocessed data sets will be available in early 2014.

  5. Small-Scale Fronts in Ultra-High Resolution Level-4 Satellite SST: Validation and Implications

    NASA Astrophysics Data System (ADS)

    Chen, H.; McKinley, G. A.

    2014-12-01

    Submesoscale oceanic fronts have been implicated in the turbulent energy cascade, and in nutrient supply into and carbon export out of the euphotic zone. However, their large-scale extent is unknown due to their characteristic small spatial (1-10km) and short time (~1 day) scales that complicate observations. Current large-scale understanding of fronts from satellite SST and ocean color is limited to a climatological view of occurrence frequency in cloud-free events. We show that useful estimates of frontal spatial coverage and structure can be derived from the recently available, merged satellite Level-4 SST product (G1SST at 1km resolution) using a gradient-based detection method in the North Atlantic subtropical gyre (28o-38oN, -75o- -45oW ). G1SST fronts are validated with in-situ fronts in continuous ship measurements from the Oleander Project. At a matching distance of Δx=5km, 79% of the G1SST fronts are in-situ fronts, and 64% of the in-situ fronts are detected by G1SST; these matches up increase with larger Δx. Comparing with in-situ velocities, ~56% of the fronts are coincident with across-track velocity jets with low-pass filter at scales > 5km,and 70% at scales > 50km, indicating that fronts are in large-scale geostrophic balance. Near-surface vertical shear predicted from thermal-wind relationship is in-phase but much smaller than (<50%) observed shear, indicating large ageostrophic shear is inclined to be co-located with surface baroclinic zones, likely due to interaction between fronts and gravity waves. For the North Atlantic subtropical gyre, we find that submesoscale fronts comprise 57±4.6% of the total surface area. Fronts are found not only in the energetic Gulf Steam region, but also are surprisingly numerous in the quiescent subtropical gyre. This finding is consistent with previous modeling studies that indicate that submesoscale fronts could help to resolve the 'nutrient--primary production' balance in oligotrophic regions.

  6. High resolution ultrasonic densitometer

    SciTech Connect

    Dress, W.B.

    1983-01-01

    The velocity of torsional stress pulses in an ultrasonic waveguide of non-circular cross section is affected by the temperature and density of the surrounding medium. Measurement of the transit times of acoustic echoes from the ends of a sensor section are interpreted as level, density, and temperature of the fluid environment surrounding that section. This paper examines methods of making these measurements to obtain high resolution, temperature-corrected absolute and relative density and level determinations of the fluid. Possible applications include on-line process monitoring, a hand-held density probe for battery charge state indication, and precise inventory control for such diverse fluids as uranium salt solutions in accountability storage and gasoline in service station storage tanks.

  7. Road Extraction Method At The Pixel And Object Level Using High Resolution Images And LIDAR Data With Evidence Theory

    NASA Astrophysics Data System (ADS)

    Rodriguez-Cuenca, Borja; Martinez de Agirre, Alex; Alonso, Maria Concepcion; del Val, Alberto

    2013-12-01

    Light Detection and Ranging (LIDAR) data provides accurate height information for objects on the Earth's surface. It is common to combine LIDAR data with satellite or aerial imagery to determine the location of different cartographic entities. In this work, an automated method for road extraction in urban areas from high resolution aerial images is presented. This method is based on the Dempster-Shafer Theory of evidence, which consists of fusing information from different information sources. The proposed method is applied to road extraction in two different ways: at the pixel level and at the object level. The results provided for both levels are compared with a ground truth created by the authors of this work in order to determine which method provides the best accuracy.

  8. Mapping the levels of eutrophication concentration in the Gulf of Mexico using high resolution ocean color data

    NASA Astrophysics Data System (ADS)

    Baruah, A.; Kearney, M.

    2007-12-01

    Coastal eutrophication is a major global environmental problem that is caused by the increased use of nutrients primarily nitrogen and phosphorus that are brought down by the rivers to the coasts. The influx of excess nutrients to the coasts degrades water quality by stimulating excess phytoplankton or macroalgae growth including some noxious and toxic algal species. During the warm summer months, oxygen levels in the Mississippi plume region of the Gulf of Mexico fall from healthy concentrations to 2-3 milligrams per liter leading to hypoxia--a low-oxygen condition that can be stressful or fatal to marine life. An improved scientific understanding of the biological processes of the inland waters of the bay to various perturbations requires the routine acquisition of high resolution time series data to synoptically characterize large scale trends and water quality parameters that can be derived only from remote sensing instruments. This study is intended to explore the capability of high resolution ocean color remote sensing data to model hypoxia through monitoring phytoplankton blooms in the Dead Zone, especially the changes in boundary conditions that often accompany tropical storms. High resolution (250 m) MODIS (Aqua) data will be used to infer the spectral characteristics of the coastal waters in the Gulf. Phytoplankton blooms will be used as a precursor for anoxia. High phytoplankton blooms would indicate a likelihood of hypoxia. The spectral characteristics of the water will then be validated with the oxygen content of the water obtained from cruise data. The Canonical Correlation technique will be used to study the correlation between the spectral characteristics of the water in the Gulf and the oxygen levels derived from cruises.

  9. High resolution core level spectroscopy of hydrogen-terminated (1 0 0) diamond.

    PubMed

    Schenk, A K; Rietwyk, K J; Tadich, A; Stacey, A; Ley, L; Pakes, C I

    2016-08-01

    Synchrotron-based photoelectron spectroscopy experiments are presented that address a long standing inconsistency in the treatment of the C1s core level of hydrogen terminated (1 0 0) diamond. Through a comparison of surface and bulk sensitive measurements we show that there is a surface related core level component to lower binding energy of the bulk diamond component; this component has a chemical shift of [Formula: see text] eV which has been attributed to carbon atoms which are part of the hydrogen termination. Additionally, our results indicate that the asymmetry of the hydrogen terminated (1 0 0) diamond C1s core level is an intrinsic aspect of the bulk diamond peak which we have attributed to sub-surface carbon layers. PMID:27299369

  10. High resolution core level spectroscopy of hydrogen-terminated (1 0 0) diamond

    NASA Astrophysics Data System (ADS)

    Schenk, A. K.; Rietwyk, K. J.; Tadich, A.; Stacey, A.; Ley, L.; Pakes, C. I.

    2016-08-01

    Synchrotron-based photoelectron spectroscopy experiments are presented that address a long standing inconsistency in the treatment of the C1s core level of hydrogen terminated (1 0 0) diamond. Through a comparison of surface and bulk sensitive measurements we show that there is a surface related core level component to lower binding energy of the bulk diamond component; this component has a chemical shift of -0.16+/- 0.05 eV which has been attributed to carbon atoms which are part of the hydrogen termination. Additionally, our results indicate that the asymmetry of the hydrogen terminated (1 0 0) diamond C1s core level is an intrinsic aspect of the bulk diamond peak which we have attributed to sub-surface carbon layers.

  11. Deployment of High Resolution Real-Time Distribution Level Metering on Maui: Preprint

    SciTech Connect

    Bank, J.

    2013-01-01

    In order to support the ongoing Maui Smart Grid demonstration project advanced metering has been deployed at the distribution transformer level in Maui Electric Company's Kihei Circuit on the Island of Maui. This equipment has been custom designed to provide accurately time-stamped Phasor and Power Quality data in real time. Additionally, irradiance sensors have been deployed at a few selected locations in proximity to photovoltaic (PV) installations. The received data is being used for validation of existing system models and for impact studies of future system hardware. Descriptions of the hardware and its installation, and some preliminary metering results are presented. Real-time circuit visualization applications for the data are also under development.

  12. Cortical representation of the human hand assessed by two levels of high-resolution EEG recordings.

    PubMed

    Houzé, Bérengère; Perchet, Caroline; Magnin, Michel; Garcia-Larrea, Luis

    2011-11-01

    Increasing interest in cortical plasticity has prompted the growing use of somatosensory evoked potentials (SEPs) to estimate changes in the cortical representation of body regions. Here, we tested the effect of different sites of hand stimulation and of the density of spatial sampling in the quality of estimation of somatosensory sources. Sources of two SEP components from the primary somatosensory cortex (N20/P20 and P45) were estimated using two levels of spatial sampling (64- vs. 128-channel) and stimulation of four distal sites in the upper limbs, including single digits (first vs. fifth) and distal nerves with comparable cortical projection (superficial branch of the radial nerve and distal ulnar nerve). The most robust separation of somatosensory sources was achieved by comparing the cortical representations of the first digit and the distal ulnar nerve territories on the N20/P20 component of SEPs. Although both the 64- and the 128-electrode montages correctly discriminated these two areas, only the 128-electrode montage was able to significantly separate sources in the other cases, notably when using first versus fifth digit stimulation. Trustworthy distinction of cortical representations was not obtainable when using the P45 component, probably because of greater activation volume, radial orientation of sources in areas 1-2 and increased variability with attention and vigilance. Assessment of tangential SEP components to stimulation of first digit versus ulnar nerve appears the best option to assess plastic somatosensory changes, especially when using relatively low-electrode sampling. PMID:21246666

  13. High Resolution Doppler Imager

    NASA Technical Reports Server (NTRS)

    Hays, Paul B.

    1999-01-01

    This report summarizes the accomplishments of the High Resolution Doppler Imager (HRDI) on UARS spacecraft during the period 4/l/96 - 3/31/99. During this period, HRDI operation, data processing, and data analysis continued, and there was a high level of vitality in the HRDI project. The HRDI has been collecting data from the stratosphere, mesosphere, and lower thermosphere since instrument activation on October 1, 1991. The HRDI team has stressed three areas since operations commenced: 1) operation of the instrument in a manner which maximizes the quality and versatility of the collected data; 2) algorithm development and validation to produce a high-quality data product; and 3) scientific studies, primarily of the dynamics of the middle atmosphere. There has been no significant degradation in the HRDI instrument since operations began nearly 8 years ago. HRDI operations are fairly routine, although we have continued to look for ways to improve the quality of the scientific product, either by improving existing modes, or by designing new ones. The HRDI instrument has been programmed to collect data for new scientific studies, such as measurements of fluorescence from plants, measuring cloud top heights, and lower atmosphere H2O.

  14. Ultra high resolution tomography

    SciTech Connect

    Haddad, W.S.

    1994-11-15

    Recent work and results on ultra high resolution three dimensional imaging with soft x-rays will be presented. This work is aimed at determining microscopic three dimensional structure of biological and material specimens. Three dimensional reconstructed images of a microscopic test object will be presented; the reconstruction has a resolution on the order of 1000 A in all three dimensions. Preliminary work with biological samples will also be shown, and the experimental and numerical methods used will be discussed.

  15. High-Resolution Autoradiography

    NASA Technical Reports Server (NTRS)

    Towe, George C; Gomberg, Henry J; Freemen, J W

    1955-01-01

    This investigation was made to adapt wet-process autoradiography to metallurgical samples to obtain high resolution of segregated radioactive elements in microstructures. Results are confined to development of the technique, which was perfected to a resolution of less than 10 microns. The radioactive samples included carbon-14 carburized iron and steel, nickel-63 electroplated samples, a powder product containing nickel-63, and tungsten-185 in N-155 alloy.

  16. Investigation of NA processes at reactive fringes: Sampling bias introduced by high resolution multi-level monitoring

    NASA Astrophysics Data System (ADS)

    Piepenbrink, M.; Ptak, T.; Grathwohl, P.

    2005-12-01

    Monitored natural attenuation is a potentially valuable risk-based remediation strategy for contaminated groundwater. The most important mass-removal process for natural attenuation is biodegradation. Certain zones or fringes of a contaminant plume offer supporting conditions for biodegradation: microbes, nutrients, contaminants and electron donors / acceptors are not only found together but also in the required reaction ratios. Due to this fact these areas show a relative rapid degradation and provide a significant contribution to the overall reduction of mass within the plume. As can be shown by high resolution numerical simulations of reactive transport in groundwater, the spatial distribution of these highly reactive zones, compared to the volume of the whole plume, is quite small and characterized by steep concentration gradients, which can not be detected using standard monitoring procedures. High resolution multi-level sampling (MLS) in the order of decimeters or less is an essential prerequisite for the investigation of NA processes at the reactive fringes at field scale. Furthermore, in contrast to technical remediation techniques which most often deal with high contaminant concentration levels close to the source zone, MNA relies heavily on the accuracy of the low concentration levels (down to the legal limits) measured in the plume. Quite often these data are strongly biased due to the monitoring equipment. This contribution presents results from ongoing controlled laboratory material tests and research on high resolution MLS at six field sites in different European countries. The focus was on a optimized site-specific hydraulic design and contaminant - MLS-material interaction. Most acceptable solutions (which means MLS resolution in the order of 0.1m) were found using sampling tubes with a small inner diameter (3-4mm). This results in a small stagnant water volume prior to sampling, but is still not problematic with respect to the flow induced

  17. Resolution of safety issues associated with the storage of high-level radioactive waste at the Hanford Site

    SciTech Connect

    Mellinger, G.B. ); Tseng, J.C. )

    1992-08-01

    A number of high-level radioactive waste (HLW) safety issues have been identified at the Hanford Site in southeastern Washington State. Resolution of these issues is one of the Highest Priorities of the US Department of Energy. The most urgent issues are the potential for explosions in certain tanks (due to periodic venting of large quantities of flammable gases, or the presence of substantial quantities of ferrocyanide and/or organic compounds in combination with nitrates-nitrites). Other safety issues have been identified as well, such as the requirement for periodic water additions to one tank to control its temperature and the release of noxious vapors from a number of tanks. Substantial progress has been made toward safety issue resolution. Potential mechanisms have been identified for the generation, retention and periodic venting of flammable gas mixtures; potential methods for controlling the periodic release behavior have been identified and in-tank testing will be initiated in 1992. Research is being conducted to determine the initiation temperatures, energetics, reaction sequences and effects of catalysts and initiators on ferrocyanide-nitrate/nitrite reactions; waste characterization on a tank-by-tank basis will be required to identify whether ferrocyanide-containing wastes are safe to store as-is or will require further treatment to eliminate safety concerns. Resolution of all of the Hanford Site HLW safety issues will be accomplished as an integral part of the Hanford Tank Waste Remediation System, that has been established to manage the storage of these wastes and their preparation for disposal.

  18. High resolution drift chambers

    SciTech Connect

    Va'vra, J.

    1985-07-01

    High precision drift chambers capable of achieving less than or equal to 50 ..mu..m resolutions are discussed. In particular, we compare so called cool and hot gases, various charge collection geometries, several timing techniques and we also discuss some systematic problems. We also present what we would consider an ''ultimate'' design of the vertex chamber. 50 refs., 36 figs., 6 tabs.

  19. High-resolution echocardiography

    NASA Technical Reports Server (NTRS)

    Nathan, R.

    1979-01-01

    High resolution computer aided ultrasound system provides two-and three-dimensional images of beating heart from many angles. System provides means for determining whether small blood vessels around the heart are blocked or if heart wall is moving normally without interference of dead and noncontracting muscle tissue.

  20. High-resolution headlamp

    NASA Astrophysics Data System (ADS)

    Gut, Carsten; Cristea, Iulia; Neumann, Cornelius

    2016-04-01

    The following article shall describe how human vision by night can be influenced. At first, front lighting systems that are already available on the market will be described, followed by their analysis with respect to the positive effects on traffic safety. Furthermore, how traffic safety by night can be increased since the introduction of high resolution headlamps shall be discussed.

  1. Enhanced High Resolution RBS System

    SciTech Connect

    Pollock, Thomas J.; Hass, James A.; Klody, George M.

    2011-06-01

    Improvements in full spectrum resolution with the second NEC high resolution RBS system are summarized. Results for 50 A ring TiN/HfO films on Si yielding energy resolution on the order of 1 keV are also presented. Detector enhancements include improved pulse processing electronics, upgraded shielding for the MCP/RAE detector, and reduced noise generated from pumping. Energy resolution measurements on spectra front edge coupled with calculations using 0.4mStr solid angle show that beam energy spread at 400 KeV from the Pelletron registered accelerator is less than 100 eV. To improve user throughput, magnet control has been added to the automatic data collection. Depth profiles derived from experimental data are discussed. For the thin films profiled, depth resolutions were on the Angstrom level with the non-linear energy/channel conversions ranging from 100 to 200 eV.

  2. Enhanced High Resolution RBS System

    NASA Astrophysics Data System (ADS)

    Pollock, Thomas J.; Hass, James A.; Klody, George M.

    2011-06-01

    Improvements in full spectrum resolution with the second NEC high resolution RBS system are summarized. Results for 50 Å TiN/HfO films on Si yielding energy resolution on the order of 1 keV are also presented. Detector enhancements include improved pulse processing electronics, upgraded shielding for the MCP/RAE detector, and reduced noise generated from pumping. Energy resolution measurements on spectra front edge coupled with calculations using 0.4mStr solid angle show that beam energy spread at 400 KeV from the Pelletron® accelerator is less than 100 eV. To improve user throughput, magnet control has been added to the automatic data collection. Depth profiles derived from experimental data are discussed. For the thin films profiled, depth resolutions were on the Angstrom level with the non-linear energy/channel conversions ranging from 100 to 200 eV.

  3. High resolution data acquisition

    DOEpatents

    Thornton, Glenn W.; Fuller, Kenneth R.

    1993-01-01

    A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock (38) pulse train (37) and analog circuitry (44) for generating a triangular wave (46) synchronously with the pulse train (37). The triangular wave (46) has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter (18, 32) forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter (26) counts the clock pulse train (37) during the interval to form a gross event interval time. A computer (52) then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.

  4. High resolution data acquisition

    DOEpatents

    Thornton, G.W.; Fuller, K.R.

    1993-04-06

    A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock, pulse train, and analog circuitry for generating a triangular wave synchronously with the pulse train (as seen in diagram on patent). The triangular wave has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter counts the clock pulse train during the interval to form a gross event interval time. A computer then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.

  5. Reconstruction of vegetation and lake level at Moon Lake, North Dakota, from high-resolution pollen and diatom data

    SciTech Connect

    Grimm, E.C.; Laird, K.R.; Mueller, P.G. |

    1995-06-01

    High-resolution fossil-pollen and diatom data from Moon Lake, North Dakota, reveal major climate and vegetation changes near the western margin of the tall-grass prairie. Fourteen AMS radiocarbon dates provide excellent time control for the past {approximately}11,800 {sup 14}C years B.P. Picea dominated during the late-glacial until it abruptly declined {approximately}10,300 B.P. During the early Holocene ({approximately}10,300-8000 B.P.), deciduous trees and shrubs (Populus, Betula, Corylus, Quercus, and especially Ulmus) were common, but prairie taxa (Poaceae, Artemisia, and Chenopodiaceae/Amaranthaceae) gradually increased. During this period the diatoms indicate the lake becoming gradually more saline as water-level fell. By {approximately}8000 B.P., salinity had increased to the point that the diatoms were no longer sensitive to further salinity increases. However, fluctuating pollen percentages of mud-flat weeds (Ambrosia and Iva) indicate frequently changing water levels during the mid-Holocene ({approximately}8000-5000 B.P.). The driest millennium was 7000-6000 B.P., when Iva annua was common. After {approximately}3000 B.P. the lake became less-saline, and the diatoms were again sensitive to changing salinity. The Medieval Warm Period and Little Ice Age are clearly evident in the diatom data.

  6. Correction to ``Extracting Man-Made Objects From High Spatial Resolution Remote Sensing Images via Fast Level Set Evolutions''

    NASA Astrophysics Data System (ADS)

    Li, Zhongbin; Shi, Wenzhong; Wang, Qunming; Miao, Zelang

    2015-10-01

    Object extraction from remote sensing images has long been an intensive research topic in the field of surveying and mapping. Most existing methods are devoted to handling just one type of object and little attention has been paid to improving the computational efficiency. In recent years, level set evolution (LSE) has been shown to be very promising for object extraction in the community of image processing and computer vision because it can handle topological changes automatically while achieving high accuracy. However, the application of state-of-the-art LSEs is compromised by laborious parameter tuning and expensive computation. In this paper, we proposed two fast LSEs for man-made object extraction from high spatial resolution remote sensing images. The traditional mean curvature-based regularization term is replaced by a Gaussian kernel and it is mathematically sound to do that. Thus a larger time step can be used in the numerical scheme to expedite the proposed LSEs. In contrast to existing methods, the proposed LSEs are significantly faster. Most importantly, they involve much fewer parameters while achieving better performance. The advantages of the proposed LSEs over other state-of-the-art approaches have been verified by a range of experiments.

  7. High resolution analysis

    NASA Technical Reports Server (NTRS)

    Robinove, C. J.

    1982-01-01

    The possibilities for the use of high spectral resolution analysis in the field of hydrology and water resources are examined. Critical gaps in scientific knowledge that must be filled before technology can be evaluated involve the spectral response of water, substances dissolved and suspended in water, and substances floating on water. The most complete mapping of oil slicks can be done in the ultraviolet region. A mean of measuring the ultraviolet reflection at the surface from satellite altitudes needs to be determined. The use of high spectral resolution sensors in a reasonable number of narrow bands may be able to sense the reflectance or emission characteristics of water and its contained materials that can be correlated with commonly used water quality variables. Technological alternative available to experiment with problems of sensing water quality are to use existing remote sensing instrumentation in an empirical mode and to develop instruments for either testing hypoteses or conducting empirical experiments.

  8. Automatic selection of flood water levels from high resolution Synthetic Aperture Radar images for assimilation into hydraulic models

    NASA Astrophysics Data System (ADS)

    Mason, D. C.; Schumann, G. J.-P.; Neal, J. C.; Garcia-Pintado, J.; Bates, P. D.

    2012-04-01

    Flood extents caused by fluvial floods in urban and rural areas may be predicted by hydraulic models. Assimilation may be used to correct the model state and improve the estimates of the model parameters or external forcing. One common observation assimilated is the water level at various points along the modelled reach. Distributed water levels may be estimated indirectly along the flood extents in SAR images by intersecting the extents with the floodplain DEM. It is necessary to select a subset of levels because adjacent levels along the flood extent will be strongly correlated and add little new information, while a large number of levels will increase the computational cost of the assimilation unnecessarily. The subset of points selected should be at positions at which the water level can be accurately determined, with the points distributed uniformly over the flood extent sufficiently sparsely that adjacent water levels are spatially uncorrelated. Although models run in hindcasting mode can provide useful information for predicting the effects of future floods, the ultimate goal must be to use SAR water levels in a forecasting model, which means that they have to be estimated in near real-time. A method for selecting such a subset automatically and in near real-time is described. The input to the method is a flood extent in both urban and rural areas extracted from a high resolution SAR image using an automatic near real-time algorithm based on object segmentation and classification, which takes into account, for example, object heights as well as their SAR backscatter, and the presence of radar shadow and layover in urban areas. The method of subset selection uses this flood extent to first select candidate waterline points in flooded rural areas having low slope, so that levels may be calculated accurately. The waterline levels and positions are corrected for the effects of double reflections between the water surface and emergent vegetation at the flood

  9. Very high resolution radiometer

    NASA Technical Reports Server (NTRS)

    Aronson, A. I.

    1974-01-01

    A primary sensor used in environmental and earth-resource observation, the Very High Resolution Radiometer (VHRR) was designed for use on the ITOS D series spacecraft. The VHRR provides a 0.47 mile resolution made possible with a mercury-cadmium-telluride detector cooled to approximately 105 K by a passive radiator cooler. The components of this system are described. The optical subsystem of the VHRR consists of a scanning mirror, a Dall-Kirkham telescope, a dichroic beam splitter, relay lenses, spectral filters, and an IR detector. Signal electronics amplify and condition the signals from the infrared and visible light detector. Sync generator electronics provides the necessary time signals. Scan-drive electronics is used for commutation of the motor winding, velocity, and phase control. A table lists the performance parameters of the VHRR.

  10. High resolution infrared measurements

    NASA Technical Reports Server (NTRS)

    Kessler, B.; Cawley, Robert

    1990-01-01

    Sample ground based cloud radiance data from a high resolution infrared sensor are shown and the sensor characteristics are presented in detail. The purpose of the Infrared Analysis Measurement and Modeling Program (IRAMMP) is to establish a deterministic radiometric data base of cloud, sea, and littoral terrain clutter to be used to advance the design and development of Infrared Search and Track (IRST) systems as well as other infrared devices. The sensor is a dual band radiometric sensor and its description, together with that of the Data Acquisition System (DAS), are given. A schematic diagram of the sensor optics is shown.

  11. An approach to investigate new particle formation in the vertical direction on the basis of high time-resolution measurements at ground level and sea level

    NASA Astrophysics Data System (ADS)

    Meng, He; Zhu, Yujiao; Evans, Greg J.; Yao, Xiaohong

    2015-02-01

    In this study, we investigated new particle formation (NPF) in the vertical direction using high time-resolution (1 s) measurements made by Fast Mobility Particle Sizers at ground level and at sea level. The coefficient of variation (CV), i.e., the ratio of standard deviation to mean value for <100-nm particle number concentration (N100) in every 30 s, is introduced as a metric to distinguish horizontal and vertical transport of atmospheric particles. We first examined the CV metric using the data collected at a semi-urban site in Toronto during the summer of 2007. The 50th and 95th percentiles of CVs associated with horizontal transport were 1-13 times smaller than those during strong vertical transport. We then compared the N100, GMD55 (geometric mean diameter of <55-nm particles) and GMD100 corresponding to the 0-5th percentiles of CVs with those corresponding to the 95-100th percentiles of CVs in five NPF events. The comparative results are discussed in terms of different formation and growth rates in the vertical direction. The similar analysis was also conducted in various marine atmospheres. We found that the CV metric can improve our understanding of NPF in the vertical direction.

  12. High-resolution satellite-based analysis of ground-level PM2.5 for the city of Montreal.

    PubMed

    Wang, Baozhen; Chen, Zhi

    2016-01-15

    Satellite remote sensing offers the opportunity to determine the spatial distribution of aerosol properties and could fill the gap of ground-level observations. Various algorithms have recently been developed in order to retrieve the aerosol optical depth (AOD) at continental scales. However, they are, to some extent, subject to coarse spatial resolutions which are not appropriate for intraurban scales as usually needed in health studies. This paper presents an improved AOD retrieval algorithm for satellite instrument MODIS at 1-km resolution for intraurban scales. The MODIS-retrieved AODs are used to derive the ground-level PM2.5 concentrations using the aerosol vertical profiles and local scale factors obtained from the GEOS-Chem model simulation. The developed method has been applied to retrieve the AODs and to evaluate the ground-level PM2.5 over the city of Montreal, Canada for 2009 on daily, monthly and annual scales. The daily and monthly results are compared with the monitoring values with correlations R(2) ranging from 0.86 to 0.93. Especially, the annual mean PM2.5 concentrations are in good agreement with the measurement values at all monitoring stations (r=0.96, slope=1.0132 ± 0.0025, intercept=0.5739 ± 0.0013). This illustrates that the developed AOD retrieval algorithm can be used to retrieve AODs at a higher spatial resolution than previous studies to further derive the regional full coverage PM2.5 results at finer spatial and temporal scales. The study results are useful in health risk assessment across this region. PMID:26473708

  13. High resolution Doppler lidar

    NASA Technical Reports Server (NTRS)

    Abreu, Vincent J.; Hays, Paul B.; Barnes, John E.

    1989-01-01

    A high resolution lidar system was implemented to measure winds in the lower atmosphere. The wind speed along the line of sight was determined by measuring the Doppler shift of the aerosol backscattered laser signal. The system in its present configuration is stable, and behaves as indicated by theoretical simulations. This system was built to demonstrate the capabilities of the detector system as a prototype for a spaceborne lidar. The detector system investigated consisted of a plane Fabry-Perot etalon, and a 12-ring anode detector. This system is generically similar to the Fabry-Perot interferometer developed for passive wind measurements on board the Dynamics Explorer satellite. That this detector system performs well in a lidar configuration was demonstrated.

  14. High Resolution Laboratory Spectroscopy

    NASA Astrophysics Data System (ADS)

    Brünken, S.; Schlemmer, S.

    2016-05-01

    In this short review we will highlight some of the recent advancements in the field of high-resolution laboratory spectroscopy that meet the needs dictated by the advent of highly sensitive and broadband telescopes like ALMA and SOFIA. Among these is the development of broadband techniques for the study of complex organic molecules, like fast scanning conventional absorption spectroscopy based on multiplier chains, chirped pulse instrumentation, or the use of synchrotron facilities. Of similar importance is the extension of the accessible frequency range to THz frequencies, where many light hydrides have their ground state rotational transitions. Another key experimental challenge is the production of sufficiently high number densities of refractory and transient species in the laboratory, where discharges have proven to be efficient sources that can also be coupled to molecular jets. For ionic molecular species sensitive action spectroscopic schemes have recently been developed to overcome some of the limitations of conventional absorption spectroscopy. Throughout this review examples demonstrating the strong interplay between laboratory and observational studies will be given.

  15. Global Anthropogenic Phosphorus Loads to Fresh Water, Grey Water Footprint and Water Pollution Levels: A High-Resolution Global Study

    NASA Astrophysics Data System (ADS)

    Mekonnen, M. M.; Hoekstra, A. Y. Y.

    2014-12-01

    We estimated anthropogenic phosphorus (P) loads to freshwater, globally at a spatial resolution level of 5 by 5 arc minute. The global anthropogenic P load to freshwater systems from both diffuse and point sources in the period 2002-2010 was 1.5 million tonnes per year. China contributed about 30% to this global anthropogenic P load. India was the second largest contributor (8%), followed by the USA (7%), Spain and Brazil each contributing 6% to the total. The domestic sector contributed the largest share (54%) to this total followed by agriculture (38%) and industry (8%). Among the crops, production of cereals had the largest contribution to the P loads (32%), followed by fruits, vegetables, and oil crops, each contributing about 15% to the total. We also calculated the resultant grey water footprints, and relate the grey water footprints per river basin to runoff to calculate the P-related water pollution level (WPL) per catchment.

  16. High resolution time interval meter

    DOEpatents

    Martin, A.D.

    1986-05-09

    Method and apparatus are provided for measuring the time interval between two events to a higher resolution than reliability available from conventional circuits and component. An internal clock pulse is provided at a frequency compatible with conventional component operating frequencies for reliable operation. Lumped constant delay circuits are provided for generating outputs at delay intervals corresponding to the desired high resolution. An initiation START pulse is input to generate first high resolution data. A termination STOP pulse is input to generate second high resolution data. Internal counters count at the low frequency internal clock pulse rate between the START and STOP pulses. The first and second high resolution data are logically combined to directly provide high resolution data to one counter and correct the count in the low resolution counter to obtain a high resolution time interval measurement.

  17. Molecular-level characterization of crude oil compounds combining reversed-phase high-performance liquid chromatography with off-line high-resolution mass spectrometry

    USGS Publications Warehouse

    Sim, Arum; Cho, Yunju; Kim, Daae; Witt, Matthias; Birdwell, Justin E.; Kim, Byung Ju; Kim, Sunghwan

    2014-01-01

    A reversed-phase separation technique was developed in a previous study (Loegel et al., 2012) and successfully applied to the de-asphalted fraction of crude oil. However, to the best of our knowledge, the molecular-level characterization of oil fractions obtained by reversed-phase high-performance liquid chromatography (HPLC) coupled with high-resolution mass spectrometry (MS) has not yet been reported. A detailed characterization of the oil fractions prepared by reversed-phase HPLC was performed in this study. HPLC fractionation was carried out on conventional crude oil and an oil shale pyrolysate. The analyses of the fractions showed that the carbon number of alkyl chains and the double bond equivalent (DBE) value were the major factors determining elution order. The compounds with larger DBE (presumably more condensed aromatic structures) and smaller carbon number (presumably compounds with short side chains) were eluted earlier but those compounds with lower DBE values (presumably less aromatic structures) and higher carbon number (presumably compounds with longer alkyl chains) eluted later in the chromatograms. This separation behavior is in good agreement with that expected from the principles of reversed-phase separation. The data presented in this study show that reversed-phase chromatography is effective in separating crude oil compounds and can be combined with ultrahigh-resolution MS data to better understand natural oils and oil shale pyrolysates.

  18. Molecular-level Analysis of Size Resolved Secondary Organic Aerosol (SOA) Samples from CALNEX Bakersfield Using High Resolution Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    O'Brien, R. E.; Laskin, A.; Laskin, J.; Weber, R.; Goldstein, A. H.

    2011-12-01

    This project focuses on analyzing the identities of molecules that comprise oligomers in size resolved aerosol fractions. Since oligomers are generally too large and polar to be measured by typical GC/MS analysis, soft ionization with high resolution mass spectrometry is used to extend the range of observable compounds. Samples collected with a microorifice uniform deposition impactor (MOUDI) during CALNEX Bakersfield in June 2010 have been analyzed with nanospray desorption electrospray ionization (nano-DESI) and an Orbitrap mass spectrometer. The nano-DESI is a soft ionization technique that allows molecular ions to be observed and the Orbitrap has sufficient resolution to determine the elemental composition of almost all species above the detection limit. A large fraction of SOA is made up of high molecular weight oligomers which are thought to form through acid catalyzed reactions of photo-chemically processed volatile organic compounds (VOC). The formation of oligomers must be influenced by the VOCs available, the amount of atmospheric sulfate and nitrate, and the magnitude of photo-chemical processing, among other potential influences. We present the elemental composition of chemical species in SOA in the 0.18 to 0.32 micron size range, providing the first multi-day data set for the study of these oligomers in atmospheric samples. Possible formation pathways and sources of observed compounds will be examined by comparison to other concurrent measurements at the site.

  19. High-resolution core-level photoemission measurements on the pentacene single crystal surface assisted by photoconduction

    NASA Astrophysics Data System (ADS)

    Nakayama, Yasuo; Uragami, Yuki; Yamamoto, Masayuki; Yonezawa, Keiichirou; Mase, Kazuhiko; Kera, Satoshi; Ishii, Hisao; Ueno, Nobuo

    2016-03-01

    Upon charge carrier transport behaviors of high-mobility organic field effect transistors of pentacene single crystal, effects of ambient gases and resultant probable ‘impurities’ at the crystal surface have been controversial. Definite knowledge on the surface stoichiometry and chemical composites is indispensable to solve this question. In the present study, high-resolution x-ray photoelectron spectroscopy (XPS) measurements on the pentacene single crystal samples successfully demonstrated a presence of a few atomic-percent of (photo-)oxidized species at the first molecular layer of the crystal surface through accurate analyses of the excitation energy (i.e. probing depth) dependence of the C1s peak profiles. Particular methodologies to conduct XPS on organic single crystal samples, without any charging nor damage of the sample in spite of its electric insulating character and fragility against x-ray irradiation, is also described in detail.

  20. High-resolution core-level photoemission measurements on the pentacene single crystal surface assisted by photoconduction.

    PubMed

    Nakayama, Yasuo; Uragami, Yuki; Yamamoto, Masayuki; Yonezawa, Keiichirou; Mase, Kazuhiko; Kera, Satoshi; Ishii, Hisao; Ueno, Nobuo

    2016-03-01

    Upon charge carrier transport behaviors of high-mobility organic field effect transistors of pentacene single crystal, effects of ambient gases and resultant probable 'impurities' at the crystal surface have been controversial. Definite knowledge on the surface stoichiometry and chemical composites is indispensable to solve this question. In the present study, high-resolution x-ray photoelectron spectroscopy (XPS) measurements on the pentacene single crystal samples successfully demonstrated a presence of a few atomic-percent of (photo-)oxidized species at the first molecular layer of the crystal surface through accurate analyses of the excitation energy (i.e. probing depth) dependence of the C1s peak profiles. Particular methodologies to conduct XPS on organic single crystal samples, without any charging nor damage of the sample in spite of its electric insulating character and fragility against x-ray irradiation, is also described in detail. PMID:26871646

  1. High Resolution Neutral Atom Microscope

    NASA Astrophysics Data System (ADS)

    Bucay, Igal; Castillo-Garza, Rodrigo; Stratis, Georgios; Raizen, Mark

    2015-03-01

    We are developing a high resolution neutral atom microscope based on metastable atom electron spectroscopy (MAES). When a metastable atom of a noble gas is near a solid, a surface electron will tunnel to an empty energy level of the metastable atom, thereby ejecting the excited electron from the atom. The emitted electrons carry information regarding the local topography and electronic, magnetic, and chemical structures of most hard materials. Furthermore, using a chromatic aberration corrected magnetic hexapole lens we expect to attain a spatial resolution below 10 nm. We will use this microscope to investigate how local phenomena can give rise to macroscopic effects in materials that cannot be probed using a scanning tunneling microscope, namely insulating transition metal oxides.

  2. High Resolution Formaldehyde Photochemistry

    NASA Astrophysics Data System (ADS)

    Ernest, C. T.; Bauer, D.; Hynes, A. J.

    2010-12-01

    Formaldehyde (HCHO) is the most abundant and most important organic carbonyl compound in the atmosphere. The sources of formaldehyde are the oxidation of methane, isoprene, acetone, and other volatile organic compounds (VOCs); fossil fuel combustion; and biomass burning. The dominant loss mechanism for formaldehyde is photolysis which occurs via two pathways: (R1) HCHO + hv → HCO + H (R2) HCHO + hv → H2 + CO The first pathway (R1) is referred to as the radical channel, while the second pathway (R2) is referred to as the molecular channel. The products of both pathways play a significant role in atmospheric chemistry. The CO that is produced in the molecular channel undergoes further oxidation to produce CO2. Under atmospheric conditions, the H atom and formyl radical that are produced in the radical channel undergo rapid reactions with O2 to produce the hydroperoxyl radical (HO2) via (R3) and (R4). (R3) HCO + O2 → HO2 + CO (R4) H + O2 → HO2 Thus, for every photon absorbed, the photolysis of formaldehyde can contribute one CO2 molecule to the global greenhouse budget or two HO2 radicals to the tropospheric HOx (OH + HO2) cycle. The HO2 radicals produced during formaldehyde photolysis have also been implicated in the formation of photochemical smog. The HO2 radicals act as radical chain carriers and convert NO to NO2, which ultimately results in the catalytic production of O3. Constraining the yield of HO2 produced via HCHO photolysis is essential for improving tropospheric chemistry models. In this study, both the absorption cross section and the quantum yield of the radical channel (R1) were measured at high resolution over the tropospherically relevant wavelength range 304-330 nm. For the cross section measurements a narrow linewidth Nd:YAG pumped dye laser was used with a multi-pass cell. Partial pressures of HCHO were kept below 0.3 torr. Simultaneous measurement of OH LIF in a flame allowed absolute calibration of the wavelength scale. Pressure

  3. High Resolution Parameter-Space from a Two-Level Model on Semi-Insulating GaAs

    NASA Astrophysics Data System (ADS)

    da Silva, S. L.; Viana, E. R.; de Oliveira, A. G.; Ribeiro, G. M.; da Silva, R. L.

    Semi-insulating Gallium Arsenide (SI-GaAs) samples experimentally show, under high electric fields and even at room temperature, negative differential conductivity in N-shaped form (NNDC). Since the most consolidated model for n-GaAs, namely, "the model", proposed by E. Schöll was not capable to generate the NNDC curve for SI-GaAs, in this work we have proposed an alternative model. The model proposed, "the two-valley model" is based on the minimal set of generation-recombination equations for two valleys inside of the conduction band, and an equation for the drift velocity as a function of the applied electric field, that covers the physical properties of the nonlinear electrical conduction of the SI-GaAs system. The "two-valley model" was capable to generate theoretically the NNDC region for the first time, and with that, we were able to build a high resolution parameter-space of the periodicity (PSP) using a Periodicity-Detection (PD) routine. In the parameter-space were observed self-organized periodic structures immersed in chaotic regions. The complex regions are presented in a "shrimp" shape rotated around a focal point, which forms in large-scale a "snail shell" shape, with intricate connections between different "shrimps". The knowledge of detailed information on parameter spaces is crucial to localize wide regions of smooth and continuous chaos.

  4. Determination of 2,3,7,8-chlorine-substituted dibenzo-p-dioxins and -furans at the part per trillion level in United States beef fat using high-resolution gas chromatography/high-resolution mass spectrometry

    NASA Technical Reports Server (NTRS)

    Ferrario, J.; Byrne, C.; McDaniel, D.; Dupuy, A. Jr; Harless, R.

    1996-01-01

    As part of the U.S. EPA Dioxin Reassessment Program, the 2,3,7,8-chlorine-substituted dibenzo-p-dioxins and furans were measured at part per trillion (ppt) levels in beef fat collected from slaughter facilities in the United States. This is the first statistically designed national survey of these compounds in the U.S. beef supply. Analyte concentrations were determined by high-resolution gas chromatography/high-resolution mass spectrometry, using isotope dilution methodology. Method limits of detection on a whole weight basis were 0.05 ppt for TCDD and 0.10 ppt for TCDF, 0.50 ppt for the pentas (PeCDDs/PeCDFs)/hexas (HxCDDs/HxCDFs)/heptas (HpCDDs/HpCDFs), and 3.00 ppt for the octas (OCDD/OCDF). Method detection and quantitation limits were established on the basis of demonstrated performance criteria utilizing fortified samples rather than by conventional signal-to-noise or variability of response methods. The background subtraction procedures developed for this study minimized the likelihood of false positives and increased the confidence associated with reported values near the detection limits. Mean and median values for each of the 2,3,7,8-Cl-substituted dioxins and furans are reported, along with the supporting information required for their interpretation. The mean toxic equivalence values for the samples are 0.35 ppt (nondetects = 0) and 0.89 ppt (nondetects = 1/2 LOD).

  5. Evaluation of the high resolution DEHM/UBM model system over Denmark and assessment of trends in air pollution levels over 36 years

    NASA Astrophysics Data System (ADS)

    Im, Ulas; Christensen, Jesper H.; Ketzel, Matthias; Ellermann, Thomas; Geels, Camilla; Hansen, Kaj M.; Hertel, Ole; Nielsen, Ole-Kenneth; Plejdrup, Marlene S.; Brandt, Jørgen

    2016-04-01

    Air pollutant levels over Denmark are simulated using the high resolution DEHM/UBM model system for the years 1979 to 2014. The system employs a hemispheric chemistry-transport model, the Danish Eulerian Hemispheric Model (DEHM) that runs on a 150 km resolution over the Northern Hemisphere, with nesting capability for higher resolutions over Europe, Northern Europe and Denmark on 50 km, 16.7 km and 5.6 km resolutions, respectively. DEHM is coupled to the Urban Background Model (UBM) that covers the whole of Denmark with a 1 km x 1 km spatial resolution. Over Denmark, the system uses data from the SPREAD emission model on a 1 km x 1 km resolution grid covering Denmark and its national sea territory. The study will describe the model system and will evaluate the performance of the model system in simulating hourly, daily and monthly mean ozone (O3), carbon monoxide (CO), nitrogen dioxide (NO2) and particulate matter (PM10 and PM2.5) concentrations against surface measurements from eight monitoring stations. We will then investigate the spatial and temporal variability of air pollutants and emissions in order to better understand the observed air pollution trends over Denmark during this 36-year period.

  6. Development of a High Resolution, Real Time, Distribution-Level Metering System and Associated Visualization, Modeling, and Data Analysis Functions

    SciTech Connect

    Bank, J.; Hambrick, J.

    2013-05-01

    NREL is developing measurement devices and a supporting data collection network specifically targeted at electrical distribution systems to support research in this area. This paper describes the measurement network which is designed to apply real-time and high speed (sub-second) measurement principles to distribution systems that are already common for the transmission level in the form of phasor measurement units and related technologies.

  7. A Computational Framework for High-Throughput Isotopic Natural Abundance Correction of Omics-Level Ultra-High Resolution FT-MS Datasets

    PubMed Central

    Carreer, William J.; Flight, Robert M.; Moseley, Hunter N. B.

    2013-01-01

    New metabolomics applications of ultra-high resolution and accuracy mass spectrometry can provide thousands of detectable isotopologues, with the number of potentially detectable isotopologues increasing exponentially with the number of stable isotopes used in newer isotope tracing methods like stable isotope-resolved metabolomics (SIRM) experiments. This huge increase in usable data requires software capable of correcting the large number of isotopologue peaks resulting from SIRM experiments in a timely manner. We describe the design of a new algorithm and software system capable of handling these high volumes of data, while including quality control methods for maintaining data quality. We validate this new algorithm against a previous single isotope correction algorithm in a two-step cross-validation. Next, we demonstrate the algorithm and correct for the effects of natural abundance for both 13C and 15N isotopes on a set of raw isotopologue intensities of UDP-N-acetyl-D-glucosamine derived from a 13C/15N-tracing experiment. Finally, we demonstrate the algorithm on a full omics-level dataset. PMID:24404440

  8. Global high resolution climate reconstructions

    NASA Astrophysics Data System (ADS)

    Schubert-Frisius, Martina; Feser, Frauke; Zahn, Matthias; von Storch, Hans; Rast, Sebastian

    2014-05-01

    Long-term reanalysis products represent an important data source for numerous climate studies. However, their coarse spatial resolution for data sets spanning the last more than 50 years and well known inhomogeneities in space and time make it difficult to derive changes in meteorological variables over time. We therefore use spectral nudging technique to down-scale the global reanalysis data to a finer resolution with a general global circulation model. With this technique the new calculated higher resolved global model fields are attracted to the large-scale state of the coarse resolution reanalysis. Besides the conservation of large-scale atmospheric information and the resulting finer topography, a surplus in contents of information in meteorological phenomena of small spatial extensions is expected. Following this strategy a simulation with the global high-resolution atmospheric model ECHAM6 (T255L95), developed by MPI-M Hamburg, will be started by spectrally nudging NCEP1 reanalysis for the time period from 1948 until 2013. Selected wavelengths of more than 1000 km of vorticity, divergence, temperature and the logarithm of the surface pressure will be imposed onto the simulated GCM counterparts at levels above 750 hPa. SST and sea ice distribution are taken from the NCEP1 data set. These simulations enable the investigation of long-term changes in meteorological phenomena; the focus is put here on intense storms. Various horizontal wavelength selections and associated vertical profiles in the strength of nudging were tested. The temporarily best configuration resulted in large time correlations for 2m-temperature and 10m wind speed at several selected locations in Germany in comparison to observations. Correlations were highest for extra-tropical regions, while over the western part of the Pacific and Indian Ocean relative low time correlations were found. In a continuing study meteorological quantities at different levels and the influences of the nudging

  9. High resolution telescope

    DOEpatents

    Massie, Norbert A.; Oster, Yale

    1992-01-01

    A large effective-aperture, low-cost optical telescope with diffraction-limited resolution enables ground-based observation of near-earth space objects. The telescope has a non-redundant, thinned-aperture array in a center-mount, single-structure space frame. It employs speckle interferometric imaging to achieve diffraction-limited resolution. The signal-to-noise ratio problem is mitigated by moving the wavelength of operation to the near-IR, and the image is sensed by a Silicon CCD. The steerable, single-structure array presents a constant pupil. The center-mount, radar-like mount enables low-earth orbit space objects to be tracked as well as increases stiffness of the space frame. In the preferred embodiment, the array has elemental telescopes with subaperture of 2.1 m in a circle-of-nine configuration. The telescope array has an effective aperture of 12 m which provides a diffraction-limited resolution of 0.02 arc seconds. Pathlength matching of the telescope array is maintained by an electro-optical system employing laser metrology. Speckle imaging relaxes pathlength matching tolerance by one order of magnitude as compared to phased arrays. Many features of the telescope contribute to substantial reduction in costs. These include eliminating the conventional protective dome and reducing on-site construction activites. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes.

  10. High resolution telescope

    SciTech Connect

    Massie, N.A.; Oster, Y.

    1990-01-01

    A large effective-aperture, low-cost optical telescope with diffraction-limited resolution enables ground-based observation of near-earth space objects. The telescope has a non-redundant, thinned-aperture array in a center-mount, single-structure space frame. It employs speckle interferometric imaging to achieve diffraction-limited resolution. The signal-to-noise ratio problem is mitigated by moving the wavelength of operation to the near-IR, and the image is sensed by a Silicon CCD. The steerable, single-structure array presents a constant pupil. The center-mount, radar-like mount enables low-earth orbit space objects to be tracked as well as increases stiffness of the space frame. In the preferred embodiment, the array has elemental telescopes with subaperture of 2.1m in a circle-of-nine configuration. The telescope array has an effective aperture of 12m which provides a diffraction-limited resolution of 0.02 arc seconds. Pathlength matching of the telescope array is maintained by an electro-optical system employing laser metrology. Speckle imaging relaxes pathlength matching tolerance by one order of magnitude as compared to phased arrays. Many features of the telescope contribute to substantial reduction in costs. These include eliminating the conventional protective dome and reducing on-site construction activities. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes. 9 figs., 1 tab.

  11. High resolution telescope

    SciTech Connect

    Massie, N.A.; Oster, Y.

    1990-12-31

    A large effective-aperture, low-cost optical telescope with diffraction-limited resolution enables ground-based observation of near-earth space objects. The telescope has a non-redundant, thinned-aperture array in a center-mount, single-structure space frame. It employs speckle interferometric imaging to achieve diffraction-limited resolution. The signal-to-noise ratio problem is mitigated by moving the wavelength of operation to the near-IR, and the image is sensed by a Silicon CCD. The steerable, single-structure array presents a constant pupil. The center-mount, radar-like mount enables low-earth orbit space objects to be tracked as well as increases stiffness of the space frame. In the preferred embodiment, the array has elemental telescopes with subaperture of 2.1m in a circle-of-nine configuration. The telescope array has an effective aperture of 12m which provides a diffraction-limited resolution of 0.02 arc seconds. Pathlength matching of the telescope array is maintained by an electro-optical system employing laser metrology. Speckle imaging relaxes pathlength matching tolerance by one order of magnitude as compared to phased arrays. Many features of the telescope contribute to substantial reduction in costs. These include eliminating the conventional protective dome and reducing on-site construction activities. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes. 9 figs., 1 tab.

  12. High spectral resolution in the solar spectrum

    NASA Technical Reports Server (NTRS)

    Baret, F.; Green, R. O.

    1994-01-01

    A session dedicated to high spectral resolution in the solar spectrum, covering topics of calibration, atmospheric correction, geology/pedology, inland water, and vegetation, is reported. The session showed a high degree of diversity in the topics and the approaches used. It was highlighted that high spectral resolution data could provide atmospherically corrected ground level calibrated reflectance values. Important advances were shown in the use of radiative transfer models applied either on water bodies or vegetation. Several studies highlighted the high degree of redundancy contained in high spectral resolution data.

  13. The High Spectral Resolution Lidar

    NASA Technical Reports Server (NTRS)

    Eloranta, E. W.; Roesler, F. L.; Sroga, J. T.

    1983-01-01

    The High Spectral Resolution Lidar (HSRL) system was developed for the remote measurement of atmospheric optical properties. Measurements are obtained by the separation of the backscattered signal into aerosol and molecular channels using a high spectral resolution Fabry-Perot optical interferometer to separate the aerosol contributions to backscatter near the laser wavelength from the Doppler-shifted molecular component of the backscatter. The transmitter consists of an optically pumped pulsed dye laser of the oscillator-amplifier design which emits at 467.88 nm, with a bandwidth of less than 0.3 pm. The transmitter and receiver share a common Schmidt-Cassegrain telescope, although they do not share the same field stop, but rather two conjugate stops. The HSRL system uses a computer-controlled dual-channel photon-counting data acquisition system providing for stable measurements at very low power levels and an excellent dynamic range. The system has been used to obtain airborne measurements of height profiles of aerosol and molecular backscatter cross sections.

  14. High-Resolution Intravital Microscopy

    PubMed Central

    Andresen, Volker; Pollok, Karolin; Rinnenthal, Jan-Leo; Oehme, Laura; Günther, Robert; Spiecker, Heinrich; Radbruch, Helena; Gerhard, Jenny; Sporbert, Anje; Cseresnyes, Zoltan; Hauser, Anja E.; Niesner, Raluca

    2012-01-01

    Cellular communication constitutes a fundamental mechanism of life, for instance by permitting transfer of information through synapses in the nervous system and by leading to activation of cells during the course of immune responses. Monitoring cell-cell interactions within living adult organisms is crucial in order to draw conclusions on their behavior with respect to the fate of cells, tissues and organs. Until now, there is no technology available that enables dynamic imaging deep within the tissue of living adult organisms at sub-cellular resolution, i.e. detection at the level of few protein molecules. Here we present a novel approach called multi-beam striped-illumination which applies for the first time the principle and advantages of structured-illumination, spatial modulation of the excitation pattern, to laser-scanning-microscopy. We use this approach in two-photon-microscopy - the most adequate optical deep-tissue imaging-technique. As compared to standard two-photon-microscopy, it achieves significant contrast enhancement and up to 3-fold improved axial resolution (optical sectioning) while photobleaching, photodamage and acquisition speed are similar. Its imaging depth is comparable to multifocal two-photon-microscopy and only slightly less than in standard single-beam two-photon-microscopy. Precisely, our studies within mouse lymph nodes demonstrated 216% improved axial and 23% improved lateral resolutions at a depth of 80 µm below the surface. Thus, we are for the first time able to visualize the dynamic interactions between B cells and immune complex deposits on follicular dendritic cells within germinal centers (GCs) of live mice. These interactions play a decisive role in the process of clonal selection, leading to affinity maturation of the humoral immune response. This novel high-resolution intravital microscopy method has a huge potential for numerous applications in neurosciences, immunology, cancer research and developmental biology

  15. Sea Level History in 3D: Early results of an ultra-high resolution MCS survey across IODP Expedition 313 drillsites

    NASA Astrophysics Data System (ADS)

    Mountain, G. S.; Kucuk, H. M.; Nedimovic, M. R.; Austin, J. A., Jr.; Fulthorpe, C.; Newton, A.; Baldwin, K.; Johnson, C.; Stanley, J. N.; Bhatnagar, T.

    2015-12-01

    Although globally averaged sea level is rising at roughly 3 mm/yr (and is accelerating), rates of local sea-level change measured at coastlines may differ from this number by a factor of two or more; at some locations, sea level may even be falling. This is due to local processes that can match or even reverse the global trend, making it clear that reliable predictions of future impacts of sea-level rise require a firm understanding of processes at the local level. The history of local sea-level change and shoreline response is contained in the geologic record of shallow-water sediments. We report on a continuing study of sea-level history in sediments at the New Jersey continental margin, where compaction and glacial isostatic adjustment are currently adding 2 mm/yr to the globally averaged rise. We collected 570 sq km of ultra-high resolution 3D MCS data aboard the R/V Langseth in June-July 2015; innovative recording and preliminary results are described by Nedimovic et al. in this same session. The goal was to provide regional context to coring and logging at IODP Exp 313 sites 27-29 that were drilled 750 m into the New Jersey shelf in 2009. These sites recovered a nearly continuous record of post-Eocene sediments from non-marine soils, estuaries, shoreface, delta front, pro-delta and open marine settings. Existing seismic data are good but are 2D high-resolution profiles at line spacings too wide to enable mapping of key nearshore features. The Langseth 3D survey used shallow towing of a tuned air gun array to preserve high frequencies, and twenty-four 50-m PCables each 12.5 apart provided 6.25 x 3.125 m common-midpoint bins along seventy-seven 50-km sail lines. With this especially dense spatial resolution of a pre-stack time migrated volume we expect to map rivers, incised valleys, barrier islands, inlets and bays, pro-delta clinoforms, tidal deltas, sequence boundaries, debris flow aprons, and more. Seismic attributes linked to sedimentary facies and

  16. Very high resolution Digital Terrain and Marine Model for Lipari island: flooding scenario induced by land subsidence and sea level rise

    NASA Astrophysics Data System (ADS)

    Anzidei, Marco; Bosman, Alessandro; Carluccio, Roberto; Carmisciano, Cosmo; Casalbore, Daniele; Chiappini, Massimo; Latino Chiocci, Francesco; D'Ajello Caracciolo, Francesca; Esposito, Alessandra; Fabris, Massimo; Muccini, Filippo; Nicolosi, Iacopo; Pietrantonio, Grazia; Sepe, Vincenzo

    2015-04-01

    Multibeam bathymetry combined with aerial digital photogrammetry, play a crucial role in the generation of ultra-high resolution digital terrain models (DTMs) of land and submarine areas. Integrating these survey techniques can be realized accurate and homogeneous DTMs along narrow coastal zones that often cannot be adequately surveyed owing to logistical limitations on collecting bathymetric data in very shallow water. Here we show results from the merging of high resolution multibeam bathymetry and aerial photogrammetric surveys, the latter also performed locally by drone surveys, integrated in the same reference system, to generate the first 3D high resolution Digital Terrain and Marine Model (DTMM) of the Lipari island (Aeolian islands, Italy). This active volcanic area is located between the Southern Tyrrhenian Sea back arc basin (Marsili basin) and the Calabrian Arc, an orogenic belt affected by a Late Quaternary extensional tectonics and uplift. In this tectonic and volcanic framework, at Lipari geodetic and archeological data show a continuous rapid land subsidence at velocities >10 mm/yr, which is the highest value among the Aeolian island. The obtained DTMM at the average resolution of 0.5 m and locally at about 0.1 m, will significantly improve geophysical and geomorphological studies of this volcanic island. Particularly, it will assist in reducing future hazards related to flooding scenario, due to the combined effect of continuous land subsidence and sea level rise. Relative sea level rise at Lipari is already causing a diffuse submersion of the coast and by the year 2100 is expected a significant flooding of the land with large impacts on the environment and the coastal installation, representing a significant hazard factor for the local population living near the shore.

  17. Ultra-high resolution AMOLED

    NASA Astrophysics Data System (ADS)

    Wacyk, Ihor; Prache, Olivier; Ghosh, Amal

    2011-06-01

    AMOLED microdisplays continue to show improvement in resolution and optical performance, enhancing their appeal for a broad range of near-eye applications such as night vision, simulation and training, situational awareness, augmented reality, medical imaging, and mobile video entertainment and gaming. eMagin's latest development of an HDTV+ resolution technology integrates an OLED pixel of 3.2 × 9.6 microns in size on a 0.18 micron CMOS backplane to deliver significant new functionality as well as the capability to implement a 1920×1200 microdisplay in a 0.86" diagonal area. In addition to the conventional matrix addressing circuitry, the HDTV+ display includes a very lowpower, low-voltage-differential-signaling (LVDS) serialized interface to minimize cable and connector size as well as electromagnetic emissions (EMI), an on-chip set of look-up-tables for digital gamma correction, and a novel pulsewidth- modulation (PWM) scheme that together with the standard analog control provides a total dimming range of 0.05cd/m2 to 2000cd/m2 in the monochrome version. The PWM function also enables an impulse drive mode of operation that significantly reduces motion artifacts in high speed scene changes. An internal 10-bit DAC ensures that a full 256 gamma-corrected gray levels are available across the entire dimming range, resulting in a measured dynamic range exceeding 20-bits. This device has been successfully tested for operation at frame rates ranging from 30Hz up to 85Hz. This paper describes the operational features and detailed optical and electrical test results for the new AMOLED WUXGA resolution microdisplay.

  18. High-resolution simulation of link-level vehicle emissions and concentrations for air pollutants in a traffic-populated eastern Asian city

    NASA Astrophysics Data System (ADS)

    Zhang, Shaojun; Wu, Ye; Huang, Ruikun; Wang, Jiandong; Yan, Han; Zheng, Yali; Hao, Jiming

    2016-08-01

    Vehicle emissions containing air pollutants created substantial environmental impacts on air quality for many traffic-populated cities in eastern Asia. A high-resolution emission inventory is a useful tool compared with traditional tools (e.g. registration data-based approach) to accurately evaluate real-world traffic dynamics and their environmental burden. In this study, Macau, one of the most populated cities in the world, is selected to demonstrate a high-resolution simulation of vehicular emissions and their contribution to air pollutant concentrations by coupling multimodels. First, traffic volumes by vehicle category on 47 typical roads were investigated during weekdays in 2010 and further applied in a networking demand simulation with the TransCAD model to establish hourly profiles of link-level vehicle counts. Local vehicle driving speed and vehicle age distribution data were also collected in Macau. Second, based on a localized vehicle emission model (e.g. the emission factor model for the Beijing vehicle fleet - Macau, EMBEV-Macau), this study established a link-based vehicle emission inventory in Macau with high resolution meshed in a temporal and spatial framework. Furthermore, we employed the AERMOD (AMS/EPA Regulatory Model) model to map concentrations of CO and primary PM2.5 contributed by local vehicle emissions during weekdays in November 2010. This study has discerned the strong impact of traffic flow dynamics on the temporal and spatial patterns of vehicle emissions, such as a geographic discrepancy of spatial allocation up to 26 % between THC and PM2.5 emissions owing to spatially heterogeneous vehicle-use intensity between motorcycles and diesel fleets. We also identified that the estimated CO2 emissions from gasoline vehicles agreed well with the statistical fuel consumption in Macau. Therefore, this paper provides a case study and a solid framework for developing high-resolution environment assessment tools for other vehicle-populated cities

  19. High Resolution Doppler Lidar

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This Grant supported the development of an incoherent lidar system to measure winds and aerosols in the lower atmosphere. During this period the following activities occurred: (1) an active feedback system was developed to improve the laser frequency stability; (2) a detailed forward model of the instrument was developed to take into account many subtle effects, such as detector non-linearity; (3) a non-linear least squares inversion method was developed to recover the Doppler shift and aerosol backscatter without requiring assumptions about the molecular component of the signal; (4) a study was done of the effects of systematic errors due to multiple etalon misalignment. It was discovered that even for small offsets and high aerosol loadings, the wind determination can be biased by as much as 1 m/s. The forward model and inversion process were modified to account for this effect; and (5) the lidar measurements were validated using rawinsonde balloon measurements. The measurements were found to be in agreement within 1-2 m/s.

  20. High resolution digital delay timer

    DOEpatents

    Martin, Albert D.

    1988-01-01

    Method and apparatus are provided for generating an output pulse following a trigger pulse at a time delay interval preset with a resolution which is high relative to a low resolution available from supplied clock pulses. A first lumped constant delay (20) provides a first output signal (24) at predetermined interpolation intervals corresponding to the desired high resolution time interval. Latching circuits (26, 28) latch the high resolution data (24) to form a first synchronizing data set (60). A selected time interval has been preset to internal counters (142, 146, 154) and corrected for circuit propagation delay times having the same order of magnitude as the desired high resolution. Internal system clock pulses (32, 34) count down the counters to generate an internal pulse delayed by an interval which is functionally related to the preset time interval. A second LCD (184) corrects the internal signal with the high resolution time delay. A second internal pulse is then applied to a third LCD (74) to generate a second set of synchronizing data (76) which is complementary with the first set of synchronizing data (60) for presentation to logic circuits (64). The logic circuits (64) further delay the internal output signal (72) to obtain a proper phase relationship of an output signal (80) with the internal pulses (32, 34). The final delayed output signal (80) thereafter enables the output pulse generator (82) to produce the desired output pulse (84) at the preset time delay interval following input of the trigger pulse (10, 12).

  1. High-Resolution X-Ray Telescopes

    NASA Technical Reports Server (NTRS)

    ODell, Stephen L.; Brissenden, Roger J.; Davis, William; Elsner, Ronald F.; Elvis, Martin; Freeman, Mark; Gaetz, Terry; Gorenstein, Paul; Gubarev, Mikhail V.

    2010-01-01

    Fundamental needs for future x-ray telescopes: a) Sharp images => excellent angular resolution. b) High throughput => large aperture areas. Generation-X optics technical challenges: a) High resolution => precision mirrors & alignment. b) Large apertures => lots of lightweight mirrors. Innovation needed for technical readiness: a) 4 top-level error terms contribute to image size. b) There are approaches to controlling those errors. Innovation needed for manufacturing readiness. Programmatic issues are comparably challenging.

  2. Approach to resolution of geologic uncertainty in the licensing of a high-level-waste repository in tuff

    SciTech Connect

    Neal, J.T.

    1983-12-31

    Resolution of uncertainty in geological information is an essential element in the licensing process for a geologic repository. Evaluation of these uncertainties within the licensing framework established by the Nuclear Regulatory Commission (NRC) is required. The Nevada Nuclear Waste Storage Investigations (NNWSI), in focusing its site characterization program on unsaturated tuff, has developed a logic hierarchy of technical issues, including key issues, issues, and information needs. Key issues are statements of major requirements whose lack could be disqualifying. An example of a key issue is the demonstration of radionuclide containment and isolation within the required release limits and transport time set by the EPA and NRC. Key issues are broken down into issues, such as the groundwater flow time to the accessible environment. Resolving uncertainty ultimately comes back to satisfying individual information needs that collectively form issues. Hydraulic conductivity is an example of an information need required to determine groundwater flow rate. Sources of uncertainty often arise in either amount, quality, or other limitations in geological data. The hierarchical structuring of geological information needs provides a perspective that allows proportionate attention to be placed on various site characterization activities, and to view them within the whole range of licensing issues that must be satisfied to ensure public health and safety. However, it may not prevent an issue from being contentious, as some geological questions are known to be emotion-laden. The mitigation of uncertainty in geological information ultimately will depend on the validity and credibility of the information presented during the licensing process.

  3. Rippled-spectrum resolution dependence on level.

    PubMed

    Supin, Alexander Ya; Popov, Vladimir V; Milekhina, Olga N; Tarakanov, Mikhail B

    2003-11-01

    Rippled-density resolution of a rippled sound spectrum (probe band) in both the presence and absence of another band (masker) was studied as a function of sound level in normal listeners. The resolvable ripple density in the probe band was measured by finding the highest ripple density at which an interchange of ripple peak and valley positions was detectable (the phase-reversal test). Probe bands were 0.5 oct wide with center frequencies of 1, 2, and 4 kHz. In the control condition (no masker), the ripple-density resolution was almost independent of sound level within a range of 40-90 dB SPL. When an on-frequency masker coincided with the probe band (that resulted in reduced ripple depth), resolution decreased slightly relative to the control condition but remained little dependent on level. With an off-frequency low-side masker, the ripple-density resolution was a little less than in the control but almost independent of level within a range of 40-60 dB SPL and progressively decreased with level increase from 70 to 90 dB SPL. The dependence on level was qualitatively similar at all probe frequencies and at various widths and positions of the low-side off-frequency masker band. PMID:14599687

  4. The High Resolution Hurricane Test

    NASA Astrophysics Data System (ADS)

    Tripoli, G. J.

    2009-09-01

    It has been suggested that an answer to the hurricane intensity forecast problem is to use very high cloud-resolving resolution in operational forecast models. In consideration of this hypothesis, the United States National Atmospheric and Oceanic Administration commissioned a major study to take place over the past 1.5 years whereby the hypothesis would be tested with 6 different hurricane models featuring different dynamics cores and different physics. These models included the GFDL hurricane, Navy COAMPS, the WRF-ARW, WRF-AHW, WRF-NMM, and the UW-NMS. The experiment design was to choose and optimal mix of historic hurricanes where good observations of intensity at land fall existed and run 5 day model forecasts with 3 different resolutions of about 9-12 km (low resolution), 3-4 km (medium resolution) and 1-1.5 km (high resolution) and document how much the forecast improved in each case. The project focused on 10 storms over 2-12, 1-5 day forecast periods, for a total of 67 simulations. Not all groups completed all 67 simulations, but there were sufficient results to reach a stunning conclusion. The results of these tests suggested that little or no improvement in intensity prediction was achieved with high resolution.

  5. Stratigraphic analysis of lake level fluctuations in Lake Ohrid: an integration of high resolution hydro-acoustic data and sediment cores

    NASA Astrophysics Data System (ADS)

    Lindhorst, K.; Vogel, H.; Krastel, S.; Wagner, B.; Hilgers, A.; Zander, A.; Schwenk, T.; Wessels, M.; Daut, G.

    2010-05-01

    Ancient Lake Ohrid is a steep sided, oligotrophic, karst lake of likely Pliocene age and often referred to as a hotspot of endemic biodiversity. This study aims on tracing significant lake level fluctuations at Lake Ohrid using high-resolution acoustic data in combination with lithological, geochemical, and chronological information from two sediment cores recovered from sub-aquatic terrace levels at ca. 32 and 55 m. According to our data, significant lake level fluctuations with prominent lowstands of ca. 60 and 35 m below the present water level occurred during MIS 6 and MIS 5, respectively. The effect of these lowstands on biodiversity in most coastal parts of the lake is negligible, due to only small changes in lake surface area, coastline, and habitat. In contrast, biodiversity in shallower areas was more severely affected due to disconnection of today sub-lacustrine springs from the main water body. Multichannel seismic data from deeper parts of the lake clearly imaged several clinoform structures stacked on top of each other. These stacked clinoforms indicate significantly lower lake levels prior to MIS 6 and a stepwise rise of water level with intermittent stillstands since its existence as water filled body, which might have caused enhanced expansion of endemic species within Lake Ohrid.

  6. Stratigraphic analysis of lake level fluctuations in Lake Ohrid: an integration of high resolution hydro-acoustic data and sediment cores

    NASA Astrophysics Data System (ADS)

    Lindhorst, K.; Vogel, H.; Krastel, S.; Wagner, B.; Hilgers, A.; Zander, A.; Schwenk, T.; Wessels, M.; Daut, G.

    2010-11-01

    Ancient Lake Ohrid is a steep-sided, oligotrophic, karst lake that was tectonically formed most likely within the Pliocene and often referred to as a hotspot of endemic biodiversity. This study aims on tracing significant lake level fluctuations at Lake Ohrid using high-resolution acoustic data in combination with lithological, geochemical, and chronological information from two sediment cores recovered from sub-aquatic terrace levels at ca. 32 and 60 m water depth. According to our data, significant lake level fluctuations with prominent lowstands of ca. 60 and 35 m below the present water level occurred during Marine Isotope Stage (MIS) 6 and MIS 5, respectively. The effect of these lowstands on biodiversity in most coastal parts of the lake is negligible, due to only small changes in lake surface area, coastline, and habitat. In contrast, biodiversity in shallower areas was more severely affected due to disconnection of today sub-lacustrine springs from the main water body. Multichannel seismic data from deeper parts of the lake clearly image several clinoform structures stacked on top of each other. These stacked clinoforms indicate significantly lower lake levels prior to MIS 6 and a stepwise rise of water level with intermittent stillstands since its existence as water-filled body, which might have caused enhanced expansion of endemic species within Lake Ohrid.

  7. High-resolution monitoring across the soil-groundwater interface - Revealing small-scale hydrochemical patterns with a novel multi-level well

    NASA Astrophysics Data System (ADS)

    Gassen, Niklas; Griebler, Christian; Stumpp, Christine

    2016-04-01

    Biogeochemical turnover processes in the subsurface are highly variable both in time and space. In order to capture this variability, high resolution monitoring systems are required. Particular in riparian zones the understanding of small-scale biogeochemical processes is of interest, as they are regarded as important buffer zones for nutrients and contaminants with high turnover rates. To date, riparian research has focused on influences of groundwater-surface water interactions on element cycling, but little is known about processes occurring at the interface between the saturated and the unsaturated zone during dynamic flow conditions. Therefore, we developed a new type of high resolution multi-level well (HR-MLW) that has been installed in the riparian zone of the Selke river. This HR-MLW for the first time enables to derive water samples both from the unsaturated and the saturated zone across one vertical profile with a spatial vertical resolution of 0.05 to 0.5 m to a depth of 4 m b.l.s. Water samples from the unsaturated zone are extracted via suction cup sampling. Samples from the saturated zone are withdrawn through glass filters and steel capillaries. Both, ceramic cups and glass filters, are installed along a 1" HDPE piezometer tube. First high resolution hydrochemical profiles revealed a distinct depth-zonation in the riparian alluvial aquifer. A shallow zone beneath the water table carried a signature isotopically and hydrochemically similar to the nearby river, while layers below 1.5 m were influenced by regional groundwater. This zonation showed temporal dynamics related to groundwater table fluctuations and microbial turnover processes. The HR-MLW delivered new insight into mixing and turnover processes between riverwater and groundwater in riparian zones, both in a temporal and spatial dimension. With these new insights, we are able to improve our understanding of dynamic turnover processes at the soil - groundwater interface and of surface

  8. High-resolution core-level spectroscopy of Si(100)c(4 × 2) and some metal-induced Si(111)√3 × √3 surfaces

    NASA Astrophysics Data System (ADS)

    Uhrberg, R. I. G.

    2001-12-01

    High-resolution core-level spectroscopy has been applied to the Si(100)c(4 × 2) surface. A correct decomposition of the Si 2p spectrum of the clean surface is important for studies of adsorption of different species and the formation of various surface reconstructions. A very well-resolved Si 2p spectrum is presented for the Si(100)c(4 × 2) surface. The decomposition of this spectrum verifies the original decomposition scheme introduced by Landemark et al (Landemark E, Karlsson C J, Chao Y-C and Uhrberg R I G 1992 Phys. Rev. Lett. 69 1588). Core-level spectra of some metal-induced Si(111)√3 × √3 surfaces are also presented. A comparison is made between the √3 × √3 reconstructions formed on Si(111) by In, a group III atom, and by Sn, a group IV atom. Both the 4d core levels of the adatoms and the Si 2p core-level spectra are discussed. Different kinds of deviation from an ideal surface may introduce a significant broadening of the core-level spectra. The effect of additional Ag atoms is discussed in the case of the Ag/Si(111)√3 × √3 surface. By reducing the surplus of Ag atoms on this surface, a Si 2p spectrum with extremely narrow components has been obtained.

  9. Relative sea level change along the Italian coasts and projections for 2100 based on high resolution DTMs and geodetic data: implications for coastal impacts

    NASA Astrophysics Data System (ADS)

    Antonioli, Fabrizio; Alessandro, Amorosi; Marco, Anzidei; Fontolan, Giorgio; De Falco, Giovanni; Lambeck, Kurt; Lo Presti, Valeria; Mastronuzzi, Giuseppe; Serpelloni, Enrico; Vecchio, Antonio

    2015-04-01

    We provide projections of sea level change in Italy for the year 2100 by adding isostatic and tectonic components to the IPCC 2013 and Rahmstorf projections. We focus on 3 areas with different tectonic behaviour: the North Adriatic coast (including Venice, subsiding); the Oristano coastal Plain (Sardinia, tectonically stable) and the Mar Piccolo in the Taranto Gulf (Apulia, uplifting). For these areas are available high resolution DTMs based on LIDAR surveys, GPS and tidal data that we use to tentatively predict a detailed multitemporal flooding scenario for the year 2100. Data are compared against predicted sea level curves providing estimates of the contribution of vertical land motion to the relative sea level change. The results are based on the most recent ANU model for the ice sheets of both hemispheres, including an alpine deglaciation model. On the basis of the eustatic, tectonic and isostatic components to the sea level change, projections are provided for marine inundation scenarios for the Italian coastal plains for the year 2100, that today are at elevations close to current sea level.

  10. Advanced very high resolution radiometer

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The advanced very high resolution radiometer development program is considered. The program covered the design, construction, and test of a breadboard model, engineering model, protoflight model, mechanical structural model, and a life test model. Special bench test and calibration equipment was also developed for use on the program.

  11. Requirements on high resolution detectors

    SciTech Connect

    Koch, A.

    1997-02-01

    For a number of microtomography applications X-ray detectors with a spatial resolution of 1 {mu}m are required. This high spatial resolution will influence and degrade other parameters of secondary importance like detective quantum efficiency (DQE), dynamic range, linearity and frame rate. This note summarizes the most important arguments, for and against those detector systems which could be considered. This article discusses the mutual dependencies between the various figures which characterize a detector, and tries to give some ideas on how to proceed in order to improve present technology.

  12. High resolution optical DNA mapping

    NASA Astrophysics Data System (ADS)

    Baday, Murat

    Many types of diseases including cancer and autism are associated with copy-number variations in the genome. Most of these variations could not be identified with existing sequencing and optical DNA mapping methods. We have developed Multi-color Super-resolution technique, with potential for high throughput and low cost, which can allow us to recognize more of these variations. Our technique has made 10--fold improvement in the resolution of optical DNA mapping. Using a 180 kb BAC clone as a model system, we resolved dense patterns from 108 fluorescent labels of two different colors representing two different sequence-motifs. Overall, a detailed DNA map with 100 bp resolution was achieved, which has the potential to reveal detailed information about genetic variance and to facilitate medical diagnosis of genetic disease.

  13. High resolution tomographic instrument development

    SciTech Connect

    Not Available

    1992-08-01

    Our recent work has concentrated on the development of high-resolution PET instrumentation reflecting in part the growing importance of PET in nuclear medicine imaging. We have developed a number of positron imaging instruments and have the distinction that every instrument has been placed in operation and has had an extensive history of application for basic research and clinical study. The present program is a logical continuation of these earlier successes. PCR-I, a single ring positron tomograph was the first demonstration of analog coding using BGO. It employed 4 mm detectors and is currently being used for a wide range of biological studies. These are of immense importance in guiding the direction for future instruments. In particular, PCR-II, a volume sensitive positron tomograph with 3 mm spatial resolution has benefited greatly from the studies using PCR-I. PCR-II is currently in the final stages of assembly and testing and will shortly be placed in operation for imaging phantoms, animals and ultimately humans. Perhaps the most important finding resulting from our previous study is that resolution and sensitivity must be carefully balanced to achieve a practical high resolution system. PCR-II has been designed to have the detection characteristics required to achieve 3 mm resolution in human brain under practical imaging situations. The development of algorithms by the group headed by Dr. Chesler is based on a long history of prior study including his joint work with Drs. Pelc and Reiderer and Stearns. This body of expertise will be applied to the processing of data from PCR-II when it becomes operational.

  14. High resolution tomographic instrument development

    SciTech Connect

    Not Available

    1992-01-01

    Our recent work has concentrated on the development of high-resolution PET instrumentation reflecting in part the growing importance of PET in nuclear medicine imaging. We have developed a number of positron imaging instruments and have the distinction that every instrument has been placed in operation and has had an extensive history of application for basic research and clinical study. The present program is a logical continuation of these earlier successes. PCR-I, a single ring positron tomograph was the first demonstration of analog coding using BGO. It employed 4 mm detectors and is currently being used for a wide range of biological studies. These are of immense importance in guiding the direction for future instruments. In particular, PCR-II, a volume sensitive positron tomograph with 3 mm spatial resolution has benefited greatly from the studies using PCR-I. PCR-II is currently in the final stages of assembly and testing and will shortly be placed in operation for imaging phantoms, animals and ultimately humans. Perhaps the most important finding resulting from our previous study is that resolution and sensitivity must be carefully balanced to achieve a practical high resolution system. PCR-II has been designed to have the detection characteristics required to achieve 3 mm resolution in human brain under practical imaging situations. The development of algorithms by the group headed by Dr. Chesler is based on a long history of prior study including his joint work with Drs. Pelc and Reiderer and Stearns. This body of expertise will be applied to the processing of data from PCR-II when it becomes operational.

  15. HRSC: High resolution stereo camera

    USGS Publications Warehouse

    Neukum, G.; Jaumann, R.; Basilevsky, A.T.; Dumke, A.; Van Gasselt, S.; Giese, B.; Hauber, E.; Head, J. W., III; Heipke, C.; Hoekzema, N.; Hoffmann, H.; Greeley, R.; Gwinner, K.; Kirk, R.; Markiewicz, W.; McCord, T.B.; Michael, G.; Muller, Jan-Peter; Murray, J.B.; Oberst, J.; Pinet, P.; Pischel, R.; Roatsch, T.; Scholten, F.; Willner, K.

    2009-01-01

    The High Resolution Stereo Camera (HRSC) on Mars Express has delivered a wealth of image data, amounting to over 2.5 TB from the start of the mapping phase in January 2004 to September 2008. In that time, more than a third of Mars was covered at a resolution of 10-20 m/pixel in stereo and colour. After five years in orbit, HRSC is still in excellent shape, and it could continue to operate for many more years. HRSC has proven its ability to close the gap between the low-resolution Viking image data and the high-resolution Mars Orbiter Camera images, leading to a global picture of the geological evolution of Mars that is now much clearer than ever before. Derived highest-resolution terrain model data have closed major gaps and provided an unprecedented insight into the shape of the surface, which is paramount not only for surface analysis and geological interpretation, but also for combination with and analysis of data from other instruments, as well as in planning for future missions. This chapter presents the scientific output from data analysis and highlevel data processing, complemented by a summary of how the experiment is conducted by the HRSC team members working in geoscience, atmospheric science, photogrammetry and spectrophotometry. Many of these contributions have been or will be published in peer-reviewed journals and special issues. They form a cross-section of the scientific output, either by summarising the new geoscientific picture of Mars provided by HRSC or by detailing some of the topics of data analysis concerning photogrammetry, cartography and spectral data analysis.

  16. High resolution tomographic instrument development

    NASA Astrophysics Data System (ADS)

    Our recent work has concentrated on the development of high-resolution PET instrumentation reflecting in part the growing importance of PET in nuclear medicine imaging. We have developed a number of positron imaging instruments and have the distinction that every instrument has been placed in operation and has had an extensive history of application for basic research and clinical study. The present program is a logical continuation of these earlier successes. PCR-I, a single ring positron tomograph was the first demonstration of analog coding using BGO. It employed 4 mm detectors and is currently being used for a wide range of biological studies. These are of immense importance in guiding the direction for future instruments. In particular, PCR-II, a volume sensitive positron tomograph with 3 mm spatial resolution has benefitted greatly from the studies using PCR-I. PCR-II is currently in the final stages of assembly and testing and will shortly be placed in operation for imaging phantoms, animals and ultimately humans. Perhaps the most important finding resulting from our previous study is that resolution and sensitivity must be carefully balanced to achieve a practical high resolution system. PCR-II has been designed to have the detection characteristics required to achieve 3 mm resolution in human brain under practical imaging situations. The development of algorithms by the group headed by Dr. Chesler is based on a long history of prior study including his joint work with Drs. Pelc and Reiderer and Stearns. This body of expertise will be applied to the processing of data from PCR-II when it becomes operational.

  17. High-resolution seismic stratigraphy of North Carolina continental margin, Cape Fear Terrace: sea level cyclicity, Paleobathymetry, and Gulf Stream dynamics

    SciTech Connect

    Matteucci, T.D.; Hine, A.C.; Snyder, S.W.; Riggs, S.

    1985-02-01

    A high-resolution seismic stratigraphic study of the Cape Fear Terrace (outer continental shelf off North Carolina) combined with biolithostratigraphic data has yielded a chronostratigraphic framework of the Quaternary sequences that comprise this portion of the North American continental margin. The Cape Fear Terrace is an anomalous, point-source, prograding, shelf-margin feature that has experienced positive relief through much of the Quaternary. This upbuilding or outbuilding followed a period of active, early Pliocene, submarine erosion in which the ancestral Gulf stream cut an erosional path beneath the presence shelf margin. The terrace was originally built up during a relative lowstand of sea level with the construction of a shelf-edge deltaic feature. Severe modification of this delta front occurred during a relative highstand of sea level as the Gulf Stream began to impinge upon the margin. The anomalously thick accumulation of shelf-edge sediments acted as a barrier to flow, inducing complex flow patterns of the Gulf Stream. Excavation of these sediments yielded a terrace feature with preferential erosion on the upstream side. Subsequent deposition in the terrace region may have resulted during fairly highstands of sea level, as evidenced by the presence of active seaward-prograding sand waves in the terrace region today. Once this shelf-edge bathymetric irregularity (the terrace) had been established, the Gulf Stream acted as a dynamic force inducing cellular flow structures within the shelf environment, which enabled sediments to be transported seaward along the paleo-shoals complex.

  18. A report on high-level nuclear waste transportation: Prepared pursuant to assembly concurrent resolution No. 8 of the 1987 Nevada Legislature

    SciTech Connect

    1988-12-01

    This report has been prepared by the staff of the State of Nevada Agency for Nuclear Projects/Nuclear Waste Project Office (NWPO) in response to Assembly Concurrent Resolution No. 8 (ACR 8), passed by the Nevada State Legislature in 1987. ACR 8 directed the NWPO, in cooperation with affected local governments and the Legislative committee on High-Level Radioactive Waste, to prepare this report which scrutinizes the US Department of Energy`s (DOE) plans for transportation of high-level radioactive waste to the proposed yucca Mountain repository, which reviews the regulatory structure under which shipments to a repository would be made and which presents NWPO`s plans for addressing high-level radioactive waste transportation issues. The report is divided into three major sections. Section 1.0 provides a review of DOE`s statutory requirements, its repository transportation program and plans, the major policy, programmatic, technical and institutional issues and specific areas of concern for the State of Nevada. Section 2.0 contains a description of the current federal, state and tribal transportation regulatory environment within which nuclear waste is shipped and a discussion of regulatory issues which must be resolved in order for the State to minimize risks and adverse impacts to its citizens. Section 3.0 contains the NWPO plan for the study and management of repository-related transportation. The plan addresses four areas, including policy and program management, regulatory studies, technical reviews and studies and institutional relationships. A fourth section provides recommendations for consideration by State and local officials which would assist the State in meeting the objectives of the plan.

  19. High-resolution sequence stratigraphic framework of carbonate deposition controlled by sea level and geostrophic bottom currents, south Florida platform margin

    SciTech Connect

    Locker, S.D.; Hine, A.C. ); Shinn, E.A. )

    1992-01-01

    High-resolution seismic reflection profiles seaward of the Marquesas Keys reveal at least eight late Quaternary sequences which downlap onto the Miocene ( ) age Pourtales Terrace at 250 m water depth. Inferred correlations are presented between these sequences and the last 7--8 sea-level cycles during the past 150 ky. The setting is unusual in that the present reef-rimmed, shallow inner shelf supplies minimal sediment to the adjacent margin where over 30 m of Holocene sediment has accumulated on portions of the outer shelf and slope. Seaward of the inner-shelf reef'' barrier, an outer-shelf terrace in 50--60 m water depth forms the upper boundary of the prograding late Quaternary sequences. These sequences exhibit both current-controlled internal geometries (e.g., sediment drifts) and sea-level controlled features such as lowstand slope erosion, transgressive unconformities, and paleoshorelines or reefs formed during lower stands of sea level. Bottom currents also severely eroded the slope at times, creating prominent unconformities. These 5th-6th order depositional sequences exhibit many features outlined by the Exxon sequence stratigraphy models. Systems tracts inferred from seismic records include lowstand wedge, shelf margin, and highstand deposits. Transgressive systems tracts are more difficult to identify and correspond to the flat outer-shelf terrace that experienced rapid lateral transgressions and regressions of sea level, and was exposed to subaerial processes during low stands. This study provides new insight on the importance of both geostrophic boundary currents and sea-level change in controlling stratigraphic development of a carbonate platform margin. Locally-thick accumulations off the Marquesas Keys may demonstrate sedimentation in response to a persistent cold cyclonic gyre in this area which causes weak counter-currents in an otherwise strong geostrophic current area.

  20. Grazer Effects on Stream Primary Production and Nitrate Utilization: Estimating Feedbacks Under Reduced Nitrate Levels at High-Temporal Resolutions from the Patch to Reach-Scale

    NASA Astrophysics Data System (ADS)

    Reijo, C. J.; Cohen, M. J.

    2015-12-01

    While nutrient enrichment is often identified as the leading cause for changes in stream gross primary production (GPP) and shifts in vegetative communities, other factors such as grazers influence overall stream structure and function. Evidence shows that grazers are a top-down control on algae in streams; however, the specific feedbacks between overall stream metabolism, grazer effects, and nutrient cycling have been variable and little is known about these interactions at nutrient levels below ambient. To further our understanding of these linkages, a nutrient depletion chamber was created and paired with high-resolution in situ sensors to estimate stream metabolism and characterize nitrate uptake (UNO3) pathways (i.e. plant uptake and denitrification). The Plexiglas chamber blocks flow and nutrient supply, inserts into upper sediments, allows light in and sediment-water-air interactions to occur. At Gum Slough Springs, FL, nitrate was reduced from ambient levels (1.40 mg N/L) to below regulatory thresholds (ca. 0.20 mg N/L) within one week. Paired chambers with and without the presence of snails (Elimia floridensis) were deployed across submerged aquatic vegetation (SAV; Vallisneria americana) and algae (Lyngbya) substrates. Results show that GPP and UNO3 were higher under SAV (70 g O2/m2/d and 300 mg NO3/m2/d, respectively) and a general lack of nutrient limitation even at low [NO3]. Grazer effects differed by vegetation type as it alleviated the reduction of NO3 levels and GPP under SAV but enhanced the decrease of algal GPP and NO3 levels over time. Continued work includes estimating grazer effects on denitrification, quantifying snail nutrient excretion contributions, and scaling up all estimates from the patch to reach level. Overall, this study will further our understanding of grazer-production-nutrient interactions within stream systems, making it possible to predict changes in feedbacks when one part of the biotic or abiotic ecosystem is altered.

  1. Continuous monitoring bed-level dynamics on an intertidal flat: introducing novel stand-alone high-resolution SED-sensors

    NASA Astrophysics Data System (ADS)

    Hu, Zhan; Lenting, Walther; van der Wal, Daphne; Bouma, Tjeerd

    2015-04-01

    Tidal flat morphology is continuously shaped by hydrodynamic force, resulting in highly dynamic bed elevations. The knowledge of short-term bed-level changes is important both for understanding sediment transport processes as well as for assessing critical ecological processes such as e.g. vegetation recruitment chances on tidal flats. Due to the labour involved, manual discontinuous measurements lack the ability to continuously monitor bed-elevation changes. Existing methods for automated continuous monitoring of bed-level changes lack vertical accuracy (e.g., Photo-Electronic Erosion Pin sensor and resistive rod) or limited in spatial application by using expensive technology (e.g., acoustic bed level sensors). A method provides sufficient accuracy with a reasonable cost is needed. In light of this, a high-accuracy sensor (2 mm) for continuously measuring short-term Surface-Elevation Dynamics (SED-sensor) was developed. This SED-sensor makes use of photovoltaic cells and operates stand-alone using internal power supply and data logging system. The unit cost and the labour in deployments is therefore reduced, which facilitates monitoring with a number of units. In this study, the performance of a group of SED-sensors is tested against data obtained with precise manual measurements using traditional Sediment Erosion Bars (SEB). An excellent agreement between the two methods was obtained, indicating the accuracy and precision of the SED-sensors. Furthermore, to demonstrate how the SED-sensors can be used for measuring short-term bed-level dynamics, two SED-sensors were deployed for 1 month at two sites with contrasting wave exposure conditions. Daily bed-level changes were obtained including a severe storm erosion event. The difference in observed bed-level dynamics at both sites was statistically explained by their different hydrodynamic conditions. Thus, the stand-alone SED-sensor can be applied to monitor sediment surface dynamics with high vertical and temporal

  2. High Resolution Thermometry for EXACT

    NASA Technical Reports Server (NTRS)

    Panek, J. S.; Nash, A. E.; Larson, M.; Mulders, N.

    2000-01-01

    High Resolution Thermometers (HRTs) based on SQUID detection of the magnetization of a paramagnetic salt or a metal alloy has been commonly used for sub-nano Kelvin temperature resolution in low temperature physics experiments. The main applications to date have been for temperature ranges near the lambda point of He-4 (2.177 K). These thermometers made use of materials such as Cu(NH4)2Br4 *2H2O, GdCl3, or PdFe. None of these materials are suitable for EXACT, which will explore the region of the He-3/He-4 tricritical point at 0.87 K. The experiment requirements and properties of several candidate paramagnetic materials will be presented, as well as preliminary test results.

  3. Resolutions adopted at the ESA Council Meeting at ministerial level

    NASA Astrophysics Data System (ADS)

    2006-02-01

    Resolution on the Agency's long-term plan for discovery and competitiveness. Resolution on the level of resources for the Agency's mandatory activities 2006 - 2010. Resolution on the evolution of the European launcher sector. Resolution on the CSG - extension until end-2008. Resolution on the evolution of the Agency. Resolution on the International Space Station programme.

  4. Layer-dependent Debye temperature and thermal expansion of Ru(0001) by means of high-energy resolution core-level photoelectron spectroscopy

    SciTech Connect

    Ferrari, Eugenio; Galli, Lorenzo; Miniussi, Elisa; Morri, Maurizio; Panighel, Mirko; Ricci, Maria; Lacovig, Paolo; Lizzit, Silvano; Baraldi, Alessandro

    2010-11-15

    The layer-dependent Debye temperature of Ru(0001) is determined by means of high-energy resolution core-level photoelectron spectroscopy measurements. The possibility to disentangle three different components in the Ru 3d{sub 5/2} spectrum of Ru(0001), originating from bulk, first-, and second-layer atoms, allowed us to follow the temperature evolution of their photoemission line shapes and binding energies. Temperature effects were detected, namely, a lattice thermal expansion and a layer-dependent phonon broadening, which was interpreted within the framework of the Hedin-Rosengren formalism based on the Debye theory. The resulting Debye temperature of the top-layer atoms is 295{+-}10 K, lower than that of the bulk (T=668{+-}5 K) and second-layer (T=445{+-}10 K) atoms. While these results are in agreement with the expected phonon softening at the surface, we show that a purely harmonic description of the motion of the surface atoms is not valid, since anharmonic effects contribute significantly to the position and line shape of the different core-level components.

  5. High resolution time interval counter

    DOEpatents

    Condreva, Kenneth J.

    1994-01-01

    A high resolution counter circuit measures the time interval between the occurrence of an initial and a subsequent electrical pulse to two nanoseconds resolution using an eight megahertz clock. The circuit includes a main counter for receiving electrical pulses and generating a binary word--a measure of the number of eight megahertz clock pulses occurring between the signals. A pair of first and second pulse stretchers receive the signal and generate a pair of output signals whose widths are approximately sixty-four times the time between the receipt of the signals by the respective pulse stretchers and the receipt by the respective pulse stretchers of a second subsequent clock pulse. Output signals are thereafter supplied to a pair of start and stop counters operable to generate a pair of binary output words representative of the measure of the width of the pulses to a resolution of two nanoseconds. Errors associated with the pulse stretchers are corrected by providing calibration data to both stretcher circuits, and recording start and stop counter values. Stretched initial and subsequent signals are combined with autocalibration data and supplied to an arithmetic logic unit to determine the time interval in nanoseconds between the pair of electrical pulses being measured.

  6. High resolution time interval counter

    DOEpatents

    Condreva, K.J.

    1994-07-26

    A high resolution counter circuit measures the time interval between the occurrence of an initial and a subsequent electrical pulse to two nanoseconds resolution using an eight megahertz clock. The circuit includes a main counter for receiving electrical pulses and generating a binary word--a measure of the number of eight megahertz clock pulses occurring between the signals. A pair of first and second pulse stretchers receive the signal and generate a pair of output signals whose widths are approximately sixty-four times the time between the receipt of the signals by the respective pulse stretchers and the receipt by the respective pulse stretchers of a second subsequent clock pulse. Output signals are thereafter supplied to a pair of start and stop counters operable to generate a pair of binary output words representative of the measure of the width of the pulses to a resolution of two nanoseconds. Errors associated with the pulse stretchers are corrected by providing calibration data to both stretcher circuits, and recording start and stop counter values. Stretched initial and subsequent signals are combined with autocalibration data and supplied to an arithmetic logic unit to determine the time interval in nanoseconds between the pair of electrical pulses being measured. 3 figs.

  7. High Resolution Scanning Reflectarray Antenna

    NASA Technical Reports Server (NTRS)

    Romanofsky, Robert R. (Inventor); Miranda, Felix A. (Inventor)

    2000-01-01

    The present invention provides a High Resolution Scanning Reflectarray Antenna (HRSRA) for the purpose of tracking ground terminals and space craft communication applications. The present invention provides an alternative to using gimbaled parabolic dish antennas and direct radiating phased arrays. When compared to a gimbaled parabolic dish, the HRSRA offers the advantages of vibration free steering without incurring appreciable cost or prime power penalties. In addition, it offers full beam steering at a fraction of the cost of direct radiating arrays and is more efficient.

  8. High-Resolution Imaging Spectrometer

    NASA Technical Reports Server (NTRS)

    Dozier, Jeff; Goetz, Alexander F. H.

    1990-01-01

    Earth resources observed in greater detail. High-Resolution Imaging Spectrometer, undergoing development for use in NASA's Earth Observing System, measures reflectance of Earth's surface in visible and near-infrared wavelengths. From an orbit around Earth, instrument scans surface of Earth in 200 wavelength bands simultaneously. Produces images enabling identification of minerals in rocks and soils, important algal pigments in oceans and inland waters, changes in spectra associated with biochemistry of plant canopies, compositions of atmospheric aerosols, sizes of grains in snow, and contamination of snow by impurities that absorb visible light.

  9. NMR Microscopy - Micron-Level Resolution.

    NASA Astrophysics Data System (ADS)

    Kwok, Wing-Chi Edmund

    1990-01-01

    Nuclear Magnetic Resonance Imaging (MRI) has been developed into a powerful and widely used diagnostic tool since the invention of techniques using linear magnetic field gradients in 1973. The variety of imaging contrasts obtainable in MRI, such as spin density, relaxation times and flow rate, gives MRI a significant advantage over other imaging techniques. For common diagnostic applications, image resolutions have been in the order of millimeters with slice thicknesses in centimeters. For many research applications, however, resolutions in the order of tens of microns or smaller are needed. NMR Imaging in these high resolution disciplines is known as NMR microscopy. Compared with conventional microscopy, NMR microscopy has the advantage of being non-invasive and non-destructive. The major obstacles of NMR microscopy are low signal-to-noise ratio and effects due to spin diffusion. To overcome these difficulties, more sensitive RF probes and very high magnetic field gradients have to be used. The most effective way to increase sensitivity is to build smaller probes. Microscope probes of different designs have been built and evaluated. Magnetic field gradient coils that can produce linear field gradients up to 450 Gauss/cm were also assembled. In addition, since microscope probes often employ remote capacitors for RF tuning, the associated signal loss in the transmission line was studied. Imaging experiments have been carried out in a 2.1 Tesla small bore superconducting magnet using the typical two-dimensional spin warp imaging technique. Images have been acquired for both biological and non-biological samples. The highest resolution was obtained in an image of a nerve bundle from the spinal cord of a racoon and has an in-plane resolution of 4 microns. These experiments have demonstrated the potential application of NMR microscopy to pathological research, nervous system study and non -destructive testings of materials. One way to further improve NMR microscopy is

  10. High-Resolution Mass Spectrometers

    NASA Astrophysics Data System (ADS)

    Marshall, Alan G.; Hendrickson, Christopher L.

    2008-07-01

    Over the past decade, mass spectrometry has been revolutionized by access to instruments of increasingly high mass-resolving power. For small molecules up to ˜400 Da (e.g., drugs, metabolites, and various natural organic mixtures ranging from foods to petroleum), it is possible to determine elemental compositions (CcHhNnOoSsPp…) of thousands of chemical components simultaneously from accurate mass measurements (the same can be done up to 1000 Da if additional information is included). At higher mass, it becomes possible to identify proteins (including posttranslational modifications) from proteolytic peptides, as well as lipids, glycoconjugates, and other biological components. At even higher mass (˜100,000 Da or higher), it is possible to characterize posttranslational modifications of intact proteins and to map the binding surfaces of large biomolecule complexes. Here we review the principles and techniques of the highest-resolution analytical mass spectrometers (time-of-flight and Fourier transform ion cyclotron resonance and orbitrap mass analyzers) and describe some representative high-resolution applications.

  11. The evolution of Ga and As core levels in the formation of Fe/GaAs (001): A high resolution soft x-ray photoelectron spectroscopic study

    SciTech Connect

    Thompson, Jamie D. W.; Neal, James R.; Shen, Tiehan H.; Morton, Simon A.; Tobin, James G.; Dan Waddill, G.; Matthew, Jim A. D.; Greig, Denis; Hopkinson, Mark

    2008-07-15

    A high resolution soft x-ray photoelectron spectroscopic study of Ga and As 3d core levels has been conducted for Fe/GaAs (001) as a function of Fe thickness. This work has provided unambiguous evidence of substrate disrupting chemical reactions induced by the Fe overlayer--a quantitative analysis of the acquired spectra indicates significantly differing behavior of Ga and As during Fe growth, and our observations have been compared with existing theoretical models. Our results demonstrate that the outdiffusing Ga and As remain largely confined to the interface region, forming a thin intermixed layer. Whereas at low coverages Fe has little influence on the underlying GaAs substrate, the onset of substrate disruption when the Fe thickness reaches 3.5 A results in major changes in the energy distribution curves (EDCs) of both As and Ga 3d cores. Our quantitative analysis suggests the presence of two additional As environments of metallic character: one bound to the interfacial region and another which, as confirmed by in situ oxidation experiments, surface segregates and persists over a wide range of overlayer thickness. Analysis of the corresponding Ga 3d EDCs found not two, but three additional environments--also metallic in nature. Two of the three are interface resident whereas the third undergoes outdiffusion at low Fe coverages. Based on the variations of the integrated intensities of each component, we present a schematic of the proposed chemical makeup of the Fe/GaAs (001) system.

  12. The evolution of Ga and As core levels in the formation of Fe/GaAs (001):A high resolution soft x-ray photoelectron spectroscopic study

    SciTech Connect

    Thompson, Jamie; Neal, James; Shen, Tiehan; Morton, Simon; Tobin, James; Waddill, George Dan; Matthew, Jim; Greig, Denis; Hopkinson, Mark

    2008-07-14

    A high resolution soft x-ray photoelectron spectroscopic study of Ga and As 3d core levels has been conducted for Fe/GaAs (001) as a function of Fe thickness. This work has provided unambiguous evidence of substrate disrupting chemical reactions induced by the Fe overlayer--a quantitative analysis of the acquired spectra indicates significantly differing behavior of Ga and As during Fe growth, and our observations have been compared with existing theoretical models. Our results demonstrate that the outdiffusing Ga and As remain largely confined to the interface region, forming a thin intermixed layer. Whereas at low coverages Fe has little influence on the underlying GaAs substrate, the onset of substrate disruption when the Fe thickness reaches 3.5 Angstrom results in major changes in the energy distribution curves (EDCs) of both As and Ga 3d cores. Our quantitative analysis suggests the presence of two additional As environments of metallic character: one bound to the interfacial region and another which, as confirmed by in situ oxidation experiments, surface segregates and persists over a wide range of overlayer thickness. Analysis of the corresponding Ga 3d EDCs found not two, but three additional environments--also metallic in nature. Two of the three are interface resident whereas the third undergoes outdiffusion at low Fe coverages. Based on the variations of the integrated intensities of each component, we present a schematic of the proposed chemical makeup of the Fe/GaAs (001) system.

  13. The Evolution of Ga and As Core Levels in the Formation of Fe/GaAs(001): A High Resolution Soft X-ray Photoelectron Spectroscopic Study

    SciTech Connect

    Thompson, J W; Neal, J R; Shen, T H; Morton, S A; Tobin, J G; Waddill, G D; Matthew, J D; Greig, D; Hopkinson, M

    2006-12-08

    A high resolution soft x-ray photoelectron spectroscopic study of Ga and As 3d core levels has been conducted for Fe/GaAs (001) as a function of Fe thickness. This work has provided unambiguous evidence of substrate disrupting chemical reactions induced by the Fe overlayer--a quantitative analysis of the acquired spectra indicates significantly differing behavior of Ga and As during Fe growth, and our observations have been compared with existing theoretical models. Our results demonstrate that the outdiffusing Ga and As remain largely confined to the interface region, forming a thin intermixed layer. Whereas at low coverages Fe has little influence on the underlying GaAs substrate, the onset of substrate disruption when the Fe thickness reaches 3.5 {angstrom} results in major changes in the energy distribution curves (EDCs) of both As and Ga 3d cores. Our quantitative analysis suggests the presence of two new As environments of metallic character; one bound to the interfacial region and another which, as confirmed by in-situ oxidation experiments, surface segregates and persists over a wide range of overlayer thickness. Analysis of the corresponding Ga 3d EDCs found not two, but three new environments--also metallic in nature. Two of the three are interface-resident whereas the third undergoes outdiffusion at low Fe coverages. Based on the variations of the integrated intensities of each component, we present a schematic of the proposed chemical make-up of the Fe/GaAs (001) system.

  14. A simple, high efficiency, high resolution spectropolarimeter

    NASA Astrophysics Data System (ADS)

    Barden, Samuel C.

    2012-09-01

    A simple concept is described that uses volume phase holographic gratings as polarizing dispersers for a high efficiency, high resolution spectropolarimeter. Although the idea has previously been mentioned in the literature as possible, such a concept has not been explored in detail. Performance analysis is presented for a VPHG spectropolarimeter concept that could be utilized for both solar and night-time astronomy. Instrumental peak efficiency can approach 100% with spectral dispersions permitting R~200,000 spectral resolution with diffraction limited telescopes. The instrument has 3-channels: two dispersed image planes with orthogonal polarization and an undispersed image plane. The concept has a range of versatility where it could be configured (with appropriate half-wave plates) for slit-fed spectroscopy or without slits for snapshot/hyperspectral/tomographic spectroscopic imaging. Multiplex gratings could also be used for the simultaneous recording of two separate spectral bands or multiple instruments could be daisy chained with beam splitters for further spectral coverage.

  15. High-resolution core-level photoemission study of Eu-induced (3x2)/(3x4) reconstruction on Ge(111)

    SciTech Connect

    Kuzmin, M.; Peraelae, R. E.; Laukkanen, P.; Ahola-Tuomi, M.; Vaeyrynen, I. J.

    2006-09-15

    We have investigated Eu-induced Ge(111)-(3x2)/(3x4) reconstruction by high-resolution core-level photoelectron spectroscopy using synchrotron radiation and low-energy electron diffraction. Recent scanning tunneling microscopy (STM) observations [Phys. Rev. B 73, 125332 (2006)] revealed that the Ge arrangement of this reconstruction can be well described in terms of the honeycomb chain-channel (HCC) geometry proposed earlier for metal/Si(111)-(3x1) and -(3x2) surfaces; the Eu atoms, however, were found to reside at two different adsorption sites in the Eu/Ge(111)-(3x2)/(3x4) reconstruction, in contrast to the equivalent adsorption sites (e.g., T4) occupied in the case of Si. The present photoemission results provide further information about the atomic arrangement of Eu/Ge(111)-(3x2)/(3x4). In particular, we show that the Ge 3d core-level data cannot be interpreted by the HCC structure with the Eu atoms adsorbed only on T4 sites, giving a spectroscopic support for the suggestions based on the earlier STM data. We consider here a modified HCC-based configuration for the Eu/Ge(111)-(3x2)/(3x4) surface where the Eu atoms occupy two different sites in the empty channel between the neighboring Ge honeycomb chains. The atomic models are discussed in the context of the Ge 3d and Eu 4f data as well as the previous results available in the literature. Finally, we propose a structural model that allows us to account for the present photoemission and earlier STM findings.

  16. High-resolution slug testing.

    PubMed

    Zemansky, G M; McElwee, C D

    2005-01-01

    The hydraulic conductivity (K) variation has important ramifications for ground water flow and the transport of contaminants in ground water. The delineation of the nature of that variation can be critical to complete characterization of a site and the planning of effective and efficient remedial measures. Site-specific features (such as high-conductivity zones) need to be quantified. Our alluvial field site in the Kansas River valley exhibits spatial variability, very high conductivities, and nonlinear behavior for slug tests in the sand and gravel aquifer. High-resolution, multilevel slug tests have been performed in a number of wells that are fully screened. A general nonlinear model based on the Navier-Stokes equation, nonlinear frictional loss, non-Darcian flow, acceleration effects, radius changes in the wellbore, and a Hvorslev model for the aquifer has been used to analyze the data, employing an automated processing system that runs within the Excel spreadsheet program. It is concluded that slug tests can provide the necessary data to identify the nature of both horizontal and vertical K variation in an aquifer and that improved delineation or higher resolution of K structure is possible with shorter test intervals. The gradation into zones of higher conductivity is sharper than seen previously, and the maximum conductivity observed is greater than previously measured. However, data from this project indicate that well development, the presence of fines, and the antecedent history of the well are important interrelated factors in regard to slug-test response and can prevent obtaining consistent results in some cases. PMID:15819943

  17. The High Time Resolution Universe

    NASA Astrophysics Data System (ADS)

    Bailes, Matthew; Possenti, Andrea; Johnston, Simon; Kramer, Michael; Burgay, Marta; Bhat, Ramesh; Keith, Michael; Burke-Spolaor, Sarah; van Straten, Willem; Stappers, Benjamin; Bates, Samuel

    2008-04-01

    The Parkes multibeam surveys heralded a new era in pulsar surveys, more than doubling the number of pulsars known. However, at high time resolution, they were severely limited by the analogue backend system, which limited the volume of sky they could effectively survey to just the local 2-3 kpc. Here we propose to use a new digital backend coupled with Australia's most powerful (16 Tflop) supercomputing cluster to conduct three ambitious surveys for millisecond and relativistic pulsars with the Parkes telescope. We hope to discover over 200 new millisecond and relativistic pulsars that will define the recycled pulsar period distribution, supply pulsars for the timing array and aid in our understanding of binary evolution.

  18. High-resolution display system for mammograms

    NASA Astrophysics Data System (ADS)

    Moskowitz, Michael J.; Huang, H. K.; Wang, Jun; Allen, Jeffrey; Sickles, Edward A.; Giles, Anthony

    1995-04-01

    A high resolution mammographic display station is implemented for clinical diagnosis and for a digital teaching file. The display consists of a specially designed, high resolution mammographic station which contains a connection to a 50 micron (variable spot size) laser film digitizer, two 2 K X 2.5 K display monitors, an image processor, a host computer, and a disk array for high speed image transfer to the display monitors. After digitization on a separate host computer, the files are immediately transferred to the display station and post- processed for viewing. The algorithm for post-processing of the digitized image applies a non- linear LUT to mimic the original film characteristics while taking into account the luminosity of the display monitors in an attempt to produce the highest digital image quality possible. Image processing functions for enhancing calcification and soft tissue are also available to assist the human observer in classification of objects within the image. Windowing and level controls are seamlessly integrated for each monitor, as well as magnification capabilities. For an image display at its full resolution (e.g., digitized at 100 microns), the magnification is accomplished with a roaming window utilizing simple 2X pixel replication. This has been found to be acceptable in preliminary tests with clinicians. Measurements of features on the 2 k displays are possible, as well. The display format accurately simulates mammographic viewing arrangements with automatic side-by-side historical, current, left and right craniocaudal, mediolateral, etc., view comparisons. This high resolution mammographic display is found to be essential for fast and accurate display of high resolution digitized mammograms. A digital mammographic teaching file has been designed and tested using this display architecture. The teaching file presents the case questions on the host display monitor, and the related images for each question are presented on the high

  19. A multidisciplinary approach to landslide structure characterization: integration of seismic tomography survey and high resolution LiDar data with the Sloping Local Base Level method.

    NASA Astrophysics Data System (ADS)

    Travelletti, Julien; Samyn, Kevin; Malet, Jean-Philippe; Grandjean, Gilles; Jaboyedoff, Michel

    2010-05-01

    A challenge to progress in the understanding of landslides is to precisely define their 3D geometry and structure as an input for volume estimation and further hydro-mechanical modelling. The objective of this work is to present a multidisciplinary approach to the geometrical modelling of the La Valette landslide by integrating seismic tomography survey (P and S wave) and high resolution LiDar data with the Sloping Local Base Level (SLBL) method. The La Valette landslide, triggered in March 1982, is one of the most important slope instability in the South French Alps. Its dimensions are 1380 m length and 290 m width, and the total volume is estimated at 3.5 106 m3. Since 2002, an important activity of the upper part of the landslide is observed, and consisted mainly in the retrogression of the crown through the opening of an important fracture over several meters and rotational slumps. The failed mass is currently loading the upper part of the mudslide and is a potential threat for the 170 residential communities. A seismic tomography survey combined to airborne and terrestrial LiDar data analysis have been carried out to identify the geological structures and discontinuities and characterize the stability of the failing mass. Seismic tomography allows direct and non-intrusive measurements of P and S waves velocities which are key parameters for the analysis of the mechanical properties of reworked and highly fissured masses. 4 seismic lines have been performed (3 of them in the direction of the slope and the other perpendicular). The 2 longest devices are composed of 24 geophones spaced by 5 meters and have a sufficient investigation depth for a large scale characterization of the landslide's structure with depth. The 2 shortest devices, composed of 24 geophones spaced by 2 meters bring information about the fracturing degree between the moving material of the landslide and the competent rock. 100gr of pentrite for each shot were used as seismic sources. The

  20. High potassium level

    MedlinePlus

    High potassium level is a problem in which the amount of potassium in the blood is higher than normal. The medical ... There are often no symptoms with a high level of potassium. When symptoms do occur, they may ...

  1. Investigation of sea-level changes and shelf break prograding sequences during the Late Quaternary offshore of Kusadasi (West Anatolia) and surroundings by high resolution seismic methods

    NASA Astrophysics Data System (ADS)

    Gurcay, Savas; Cifci, Gunay; Dondurur, Derman; Okay, Seda; Atgin, Orhan; Ozel, Ozkan; Mert Kucuk, Hilmi

    2016-04-01

    High Resolution multi-channel seismic reflection and Chirp data were collected by K. Piri Reis, research vessel of Dokuz Eylül University, in the central Aegean coast of the West Anatolia by research cruises carried out in 2005 and 2008, respectively. Submarine stratigraphic and structural features of Sıǧacık Gulf, Kuşadası Gulf and surroundings were investigated under this survey. The data were processed and interpreted in SeisLab, D.E.U. Marine Sciences and Technology seismic laboratory. Thirteen distinct unconformities can be traced below the study area that separate thirteen progradational stacked paleo-delta sequences (Lob1-Lob13) on seismic profiles following and cutting each other. As a result of comparison with the oxygen isotopic stages (δ18), these deltas (Lob1-L13) were interpreted that they have been deposited during the sea-level lowstands within Pleistocene glacial stages. In the study area the basement surface which observed as the lowest unconformity surface of the seismic sections was called 'Acoustic Basement'. This basement which traced approximately all of the seismic sections has generally quite wavy surface and underlain the upper seismic units. It was observed that these seismic units which terminated their formation in Pleistocene (Lob1-Lob13) and Holocene period were cut and uplifted by acoustic basement, like an intrusion. These type deformations were interpreted as a result of magmatic intrusion into these upper seismic units occurred in Late Pleistocene and Holocene period. Tectonic and structural interpretation was carried out to constitute the submarine active tectonic map of the study area by correlated active faults identified on seismic sections. Submarine active tectonic map and, basement topography and sediment thickness map were correlated together to present the relationship between tectonic deformation and stratigraphy.

  2. Three-dimensional (3D) microarchitecture correlations with 2D projection image gray-level variations assessed by trabecular bone score using high-resolution computed tomographic acquisitions: effects of resolution and noise.

    PubMed

    Winzenrieth, Renaud; Michelet, Franck; Hans, Didier

    2013-01-01

    The aim of the present study is to determine the level of correlation between the 3-dimensional (3D) characteristics of trabecular bone microarchitecture, as evaluated using microcomputed tomography (μCT) reconstruction, and trabecular bone score (TBS), as evaluated using 2D projection images directly derived from 3D μCT reconstruction (TBSμCT). Moreover, we have evaluated the effects of image degradation (resolution and noise) and X-ray energy of projection on these correlations. Thirty human cadaveric vertebrae were acquired on a microscanner at an isotropic resolution of 93 μm. The 3D microarchitecture parameters were obtained using MicroView (GE Healthcare, Wauwatosa, MI). The 2D projections of these 3D models were generated using the Beer-Lambert law at different X-ray energies. Degradation of image resolution was simulated (from 93 to 1488 μm). Relationships between 3D microarchitecture parameters and TBSμCT at different resolutions were evaluated using linear regression analysis. Significant correlations were observed between TBSμCT and 3D microarchitecture parameters, regardless of the resolution. Correlations were detected that were strongly to intermediately positive for connectivity density (0.711 ≤ r² ≤ 0.752) and trabecular number (0.584 ≤ r² ≤ 0.648) and negative for trabecular space (-0.407 ≤ r² ≤ -0.491), up to a pixel size of 1023 μm. In addition, TBSμCT values were strongly correlated between each other (0.77 ≤ r² ≤ 0.96). Study results show that the correlations between TBSμCT at 93 μm and 3D microarchitecture parameters are weakly impacted by the degradation of image resolution and the presence of noise. PMID:22749406

  3. Practising high-resolution anoscopy.

    PubMed

    Palefsky, Joel M

    2012-12-01

    The incidence of anal cancer is increasing in the general population among both men and women. The incidence is particularly high among men who have sex with men and HIV-infected men and women. Anal cancer is similar to cervical cancer and is associated with human papillomavirus (HPV). Anal cancer is potentially preventable through primary prevention with HPV vaccination or secondary prevention. Secondary prevention is modelled after cervical cancer, where cytology is used as a screening tool to identify women who need colposcopy. Colposcopy includes magnification of the cervix, which, along with acetic acid and Lugol's solution, is used to visualise and biopsy potentially precancerous lesions, enabling treatment before progression to cervical cancer. Anal cancer is likely preceded by high-grade anal intraepithelial neoplasia (HGAIN), and a colposcope with acetic acid and Lugol's solution may similarly be used to visualise HGAIN to permit biopsy and treatment in an effort to prevent anal cancer. To distinguish it from cervical colposcopy, this technique is called high-resolution anoscopy (HRA). Many of the features that distinguish low-grade AIN from HGAIN are similar to those of the cervix, but HRA poses several additional challenges compared with cervical colposcopy. These include uneven topography; obscuring of lesions due to haemorrhoids, folds, stool or mucus; or lesions being located at the base of folds and anal glands. Consequently, a long learning curve is typically required before becoming fully competent in this technique. The technique of HRA, its uses and challenges in prevention of anal cancer are described in this article. PMID:23380236

  4. High resolution optoelectronic retinal prosthesis

    NASA Astrophysics Data System (ADS)

    Loudin, Jim; Dinyari, Rostam; Huie, Phil; Butterwick, Alex; Peumans, Peter; Palanker, Daniel

    2009-02-01

    Electronic retinal prostheses seek to restore sight in patients with retinal degeneration by delivering pulsed electric currents to retinal neurons via an array of microelectrodes. Most implants use inductive or optical transmission of information and power to an intraocular receiver, with decoded signals subsequently distributed to retinal electrodes through an intraocular cable. Surgical complexity could be minimized by an "integrated" prosthesis, in which both power and data are delivered directly to the stimulating array without any discrete components or cables. We present here an integrated retinal prosthesis system based on a photodiode array implant. Video frames are processed and imaged onto the retinal implant by a video goggle projection system operating at near-infrared wavelengths (~ 900 nm). Photodiodes convert light into pulsed electric current, with charge injection maximized by specially optimized series photodiode circuits. Prostheses of three different pixel densities (16 pix/mm2, 64 pix/mm2, and 256 pix/mm2) have been designed, simulated, and prototyped. Retinal tissue response to subretinal implants made of various materials has been investigated in RCS rats. The resulting prosthesis can provide sufficient charge injection for high resolution retinal stimulation without the need for implantation of any bulky discrete elements such as coils or tethers. In addition, since every pixel functions independently, pixel arrays may be placed separately in the subretinal space, providing visual stimulation to a larger field of view.

  5. High resolution auditory perception system

    NASA Astrophysics Data System (ADS)

    Alam, Iftekhar; Ghatol, Ashok

    2005-04-01

    Blindness is a sensory disability which is difficult to treat but can to some extent be helped by artificial aids. The paper describes the design aspects of a high resolution auditory perception system, which is designed on the principle of air sonar with binaural perception. This system is a vision substitution aid for enabling blind persons. The blind person wears ultrasonic eyeglasses which has ultrasonic sensor array embedded on it. The system has been designed to operate in multiresolution modes. The ultrasonic sound from the transmitter array is reflected back by the objects, falling in the beam of the array and is received. The received signal is converted to a sound signal, which is presented stereophonically for auditory perception. A detailed study has been done as the background work required for the system implementation; the appropriate range analysis procedure, analysis of space-time signals, the acoustic sensors study, amplification methods and study of the removal of noise using filters. Finally the system implementation including both the hardware and the software part of it has been described. Experimental results on actual blind subjects and inferences obtained during the study have also been included.

  6. High Resolution, High Frame Rate Video Technology

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Papers and working group summaries presented at the High Resolution, High Frame Rate Video (HHV) Workshop are compiled. HHV system is intended for future use on the Space Shuttle and Space Station Freedom. The Workshop was held for the dual purpose of: (1) allowing potential scientific users to assess the utility of the proposed system for monitoring microgravity science experiments; and (2) letting technical experts from industry recommend improvements to the proposed near-term HHV system. The following topics are covered: (1) State of the art in the video system performance; (2) Development plan for the HHV system; (3) Advanced technology for image gathering, coding, and processing; (4) Data compression applied to HHV; (5) Data transmission networks; and (6) Results of the users' requirements survey conducted by NASA.

  7. Planetary Atmospheres at High Resolution

    NASA Astrophysics Data System (ADS)

    Gurwell, M.; Butler, B.; Moullet, A.

    2013-10-01

    The long millimeter through submillimeter bands are particularly well suited for studying the wide variety of planetary atmospheres in our solar system. Temperatures ranging from a few 10s to hundreds of degrees, coupled with typically high densities (relative to the ISM) mean that thermal ‘continuum’ emission can be strong and molecular rotational transitions can be well-populated. Large bodies (Jovian and terrestrial planets) can be reasonably well studied by current interferometers such as the Submillimeter Array, IRAM Plateau de Bure Interferometer, and Combined Array for Research in Millimeter-wave Astronomy, yet many smaller bodies with atmospheres can only be crudely studied, primarily due to lack of sensitivity on baselines long enough to well resolve the object. Newly powerful interferometers such as the Atacama Large Millimeter/Submillimeter Array will usher in a new era of planetary atmospheric exploration. The vast sensitivity and spatial resolution of these arrays will increase our ability to image all bodies with extremely fine fidelity (due to the large number of antennas), and for study of smaller objects by resolving their disks into many pixels while providing the sensitivity necessary to detect narrow and/or weak line emission. New science topics will range from detailed mapping of HDO, ClO, and sulfur species in the mesosphere of Venus and PH3 and H2S in the upper tropospheres of the gas and ice giants, high SNR mapping of winds on Mars, Neptune and Titan, down to spectroscopic imaging of volcanic eruptions within the tenuous atmosphere on Io, resolved imaging of CO and other species in the atmosphere of Pluto, and even potentially detection of gases within the plumes of Enceladus.

  8. High blood cholesterol levels

    MedlinePlus

    ... gov/ency/article/000403.htm High blood cholesterol levels To use the sharing features on this page, ... called "bad" cholesterol For many people, abnormal cholesterol levels are partly due to an unhealthy lifestyle. This ...

  9. High-resolution phylogenetic microbial community profiling.

    PubMed

    Singer, Esther; Bushnell, Brian; Coleman-Derr, Devin; Bowman, Brett; Bowers, Robert M; Levy, Asaf; Gies, Esther A; Cheng, Jan-Fang; Copeland, Alex; Klenk, Hans-Peter; Hallam, Steven J; Hugenholtz, Philip; Tringe, Susannah G; Woyke, Tanja

    2016-08-01

    Over the past decade, high-throughput short-read 16S rRNA gene amplicon sequencing has eclipsed clone-dependent long-read Sanger sequencing for microbial community profiling. The transition to new technologies has provided more quantitative information at the expense of taxonomic resolution with implications for inferring metabolic traits in various ecosystems. We applied single-molecule real-time sequencing for microbial community profiling, generating full-length 16S rRNA gene sequences at high throughput, which we propose to name PhyloTags. We benchmarked and validated this approach using a defined microbial community. When further applied to samples from the water column of meromictic Sakinaw Lake, we show that while community structures at the phylum level are comparable between PhyloTags and Illumina V4 16S rRNA gene sequences (iTags), variance increases with community complexity at greater water depths. PhyloTags moreover allowed less ambiguous classification. Last, a platform-independent comparison of PhyloTags and in silico generated partial 16S rRNA gene sequences demonstrated significant differences in community structure and phylogenetic resolution across multiple taxonomic levels, including a severe underestimation in the abundance of specific microbial genera involved in nitrogen and methane cycling across the Lake's water column. Thus, PhyloTags provide a reliable adjunct or alternative to cost-effective iTags, enabling more accurate phylogenetic resolution of microbial communities and predictions on their metabolic potential. PMID:26859772

  10. High resolution laser imaging system

    NASA Astrophysics Data System (ADS)

    Kyle, Thomas G.

    1989-07-01

    Computations indicate that a synthetic aperture laser imaging system can provide images with 10-cm resolution at satellite ranges using a 10-W CW laser. When imaging satellites from the ground, the synthetic aperture system reduces atmospheric degradations. The system uses 20-cm diam receiver optics. The low laser power is made possible by using separate transmitter and receiver optics and coded pulses with a 50 percent transmitter duty cycle. The coded pulses are derived from Hadamard matrices for which there is an efficient algorithm to transform the received data into images. The synthetic aperture yields spatial resolutions independent of range, and the coded pulses result in an effective range dependence of r exp-2 instead of r exp-4.

  11. Taking qPCR to a higher level: Analysis of CNV reveals the power of high throughput qPCR to enhance quantitative resolution.

    PubMed

    Weaver, Suzanne; Dube, Simant; Mir, Alain; Qin, Jian; Sun, Gang; Ramakrishnan, Ramesh; Jones, Robert C; Livak, Kenneth J

    2010-04-01

    This paper assesses the quantitative resolution of qPCR using copy number variation (CNV) as a paradigm. An error model is developed for real-time qPCR data showing how the precision of CNV determination varies with the number of replicates. Using samples with varying numbers of X chromosomes, experimental data demonstrates that real-time qPCR can readily distinguish four copes from five copies, which corresponds to a 1.25-fold difference in relative quantity. Digital PCR is considered as an alternative form of qPCR. For digital PCR, an error model is shown that relates the precision of CNV determination to the number of reaction chambers. The quantitative capability of digital PCR is illustrated with an experiment distinguishing four and five copies of the human gene MRGPRX1. For either real-time qPCR or digital PCR, practical application of these models to achieve enhanced quantitative resolution requires use of a high throughput PCR platform that can simultaneously perform thousands of reactions. Comparing the two methods, real-time qPCR has the advantage of throughput and digital PCR has the advantage of simplicity in terms of the assumptions made for data analysis. PMID:20079846

  12. High Spectral Resolution Lidar Data

    DOE Data Explorer

    Eloranta, Ed

    2004-12-01

    The HSRL provided calibrated vertical profiles of optical depth, backscatter cross section and depoloarization at a wavelength of 532 nm. Profiles were acquired at 2.5 second intervals with 7.5 meter resolution. Profiles extended from an altitude of 100 m to 30 km in clear air. The lidar penetrated to a maximum optical depth of ~ 4 under cloudy conditions. Our data contributed directly to the aims of the M-PACE experiment, providing calibrated optical depth and optical backscatter measurements which were not available from any other instrument.

  13. High Resolution PDF Measurements on Ag Nanoparticles

    SciTech Connect

    Rocha, Tulio C. R.; Martin, Chris; Kycia, Stefan; Zanchet, Daniela

    2009-01-29

    The quantitative analysis of structural defects in Ag nanoparticles was addressed in this work. We performed atomic scale structural characterization by a combination of x-ray diffraction (XRD) using the Pair Distribution Function analysis (PDF) and High Resolution Transmission Electron Microscopy (HRTEM). The XRD measurements were performed using an innovative instrumentation setup to provide high resolution PDF patterns.

  14. High resolution scintillation detector with semiconductor readout

    DOEpatents

    Levin, Craig S.; Hoffman, Edward J.

    2000-01-01

    A novel high resolution scintillation detector array for use in radiation imaging such as high resolution Positron Emission Tomography (PET) which comprises one or more parallelepiped crystals with at least one long surface of each crystal being in intimate contact with a semiconductor photodetector such that photons generated within each crystal by gamma radiation passing therethrough is detected by the photodetector paired therewith.

  15. Sea level history in 3D: Data acquisition and processing for an ultra-high resolution MCS survey across IODP Expedition 313 drillsite

    NASA Astrophysics Data System (ADS)

    Nedimovic, M. R.; Mountain, G. S.; Austin, J. A., Jr.; Fulthorpe, C.; Aali, M.; Baldwin, K.; Bhatnagar, T.; Johnson, C.; Küçük, H. M.; Newton, A.; Stanley, J.

    2015-12-01

    In June-July 2015, we acquired the first 3D/2D hybrid (short/long streamer) multichannel seismic (MCS) reflection dataset. These data were collected simultaneously across IODP Exp. 313 drillsites, off New Jersey, using R/V Langsethand cover ~95% of the planned 12x50 km box. Despite the large survey area, the lateral and vertical resolution for the 3D dataset is almost a magnitude of order higher than for data gathered for standard petroleum exploration. Such high-resolution was made possible by collection of common midpoint (CMP) lines whose combined length is ~3 times the Earth's circumference (~120,000 profile km) and a source rich in high-frequencies. We present details on the data acquisition, ongoing data analysis, and preliminary results. The science driving this project is presented by Mountain et al. The 3D component of this innovative survey used an athwartship cross cable, extended laterally by 2 barovanes roughly 357.5 m apart and trailed by 24 50-m P-Cables spaced ~12.5 m with near-trace offset of 53 m. Each P-Cable had 8 single hydrophone groups spaced at 6.25 m for a total of 192 channels. Record length was 4 s and sample rate 0.5 ms, with no low cut and an 824 Hz high cut filter. We ran 77 sail lines spaced ~150 m. Receiver locations were determined using 2 GPS receivers mounted on floats and 2 compasses and depth sensors per streamer. Streamer depths varied from 2.1 to 3.7 m. The 2D component used a single 3 km streamer, with 240 9-hydrophone groups spaced at 12.5 m, towed astern with near-trace offset of 229 m. The record length was 4 s and sample rate 0.5 ms, with low cut filter at 2 Hz and high cut at 412 Hz. Receiver locations were recorded using GPS at the head float and tail buoy, combined with 12 bird compasses spaced ~300 m. Nominal streamer depth was 4.5 m. The source for both systems was a 700 in3 linear array of 4 Bolt air guns suspended at 4.5 m towing depth, 271.5 m behind the ship's stern. Shot spacing was 12.5 m. Data analysis to

  16. High-resolution phylogenetic microbial community profiling

    SciTech Connect

    Singer, Esther; Coleman-Derr, Devin; Bowman, Brett; Schwientek, Patrick; Clum, Alicia; Copeland, Alex; Ciobanu, Doina; Cheng, Jan-Fang; Gies, Esther; Hallam, Steve; Tringe, Susannah; Woyke, Tanja

    2014-03-17

    The representation of bacterial and archaeal genome sequences is strongly biased towards cultivated organisms, which belong to merely four phylogenetic groups. Functional information and inter-phylum level relationships are still largely underexplored for candidate phyla, which are often referred to as microbial dark matter. Furthermore, a large portion of the 16S rRNA gene records in the GenBank database are labeled as environmental samples and unclassified, which is in part due to low read accuracy, potential chimeric sequences produced during PCR amplifications and the low resolution of short amplicons. In order to improve the phylogenetic classification of novel species and advance our knowledge of the ecosystem function of uncultivated microorganisms, high-throughput full length 16S rRNA gene sequencing methodologies with reduced biases are needed. We evaluated the performance of PacBio single-molecule real-time (SMRT) sequencing in high-resolution phylogenetic microbial community profiling. For this purpose, we compared PacBio and Illumina metagenomic shotgun and 16S rRNA gene sequencing of a mock community as well as of an environmental sample from Sakinaw Lake, British Columbia. Sakinaw Lake is known to contain a large age of microbial species from candidate phyla. Sequencing results show that community structure based on PacBio shotgun and 16S rRNA gene sequences is highly similar in both the mock and the environmental communities. Resolution power and community representation accuracy from SMRT sequencing data appeared to be independent of GC content of microbial genomes and was higher when compared to Illumina-based metagenome shotgun and 16S rRNA gene (iTag) sequences, e.g. full-length sequencing resolved all 23 OTUs in the mock community, while iTags did not resolve closely related species. SMRT sequencing hence offers various potential benefits when characterizing uncharted microbial communities.

  17. A high-resolution vehicle emission inventory for China

    NASA Astrophysics Data System (ADS)

    Zheng, B.; Zhang, Q.; He, K.; Huo, H.; Yao, Z.; Wang, X.

    2012-12-01

    Developing high resolution emission inventory is an essential task for air quality modeling and management. However, current vehicle emission inventories in China are usually developed at provincial level and then allocated to grids based on various spatial surrogates, which is difficult to get high spatial resolution. In this work, we developed a new approach to construct a high-resolution vehicle emission inventory for China. First, vehicle population at county level were estimated by using the relationship between per-capita GDP and vehicle ownership. Then the Weather Research and Forecasting (WRF) model were used to drive the International Vehicle Emission (IVE) model to get monthly emission factors for each county. Finally, vehicle emissions by county were allocated to grids with 5-km horizon resolution by using high-resolution road network data. This work provides a better understanding of spatial representation of vehicle emissions in China and can benefit both air quality modeling and management with improved spatial accuracy.

  18. High level nuclear waste

    SciTech Connect

    Crandall, J L

    1980-01-01

    The DOE Division of Waste Products through a lead office at Savannah River is developing a program to immobilize all US high-level nuclear waste for terminal disposal. DOE high-level wastes include those at the Hanford Plant, the Idaho Chemical Processing Plant, and the Savannah River Plant. Commercial high-level wastes, for which DOE is also developing immobilization technology, include those at the Nuclear Fuel Services Plant and any future commercial fuels reprocessing plants. The first immobilization plant is to be the Defense Waste Processing Facility at Savannah River, scheduled for 1983 project submission to Congress and 1989 operation. Waste forms are still being selected for this plant. Borosilicate glass is currently the reference form, but alternate candidates include concretes, calcines, other glasses, ceramics, and matrix forms.

  19. High resolution guided wave pipe inspection

    NASA Astrophysics Data System (ADS)

    Velichko, Alexander; Wilcox, Paul D.

    2009-03-01

    Commercial guided wave inspection systems provide rapid screening of pipes, but limited sizing capability for small defects. However, accurate detection and sizing of small defects is essential for assessing the integrity of inaccessible pipe regions where guided waves provide the only possible inspection mechanism. In this paper an array-based approach is presented that allows guided waves to be focused on both transmission and reception to produce a high resolution image of a length of pipe. In the image, it is shown that a signal to coherent noise ratio of over 40 dB with respect to the reflected signal from a free end of pipe can be obtained, even taking into account typical levels of experimental uncertainty in terms of transducer positioning, wave velocity etc. The combination of an image with high resolution and a 40 dB dynamic range enables the detection of very small defects. It also allows the in-plane shape of defects over a certain size to be observed directly. Simulations are used to estimate the detection and sizing capability of the system for crack-like defects. Results are presented from a prototype system that uses EMATs to fully focus pipe guided wave modes on both transmission and reception in a 12 inch diameter stainless steel pipe. The 40 dB signal to coherent noise ratio is obtained experimentally and a 2 mm diameter (0.08 wavelengths) half-thickness hole is shown to be detectable.

  20. Progress on LAMOST High Resolution Spectrograph Project

    NASA Astrophysics Data System (ADS)

    Zhang, KaI

    2015-08-01

    To explore more science case, LAMOST doesn't only has strong power on celestial spectral survey but also reserves an access to high resolution spectrograph with a few optional fibers. This commissioned spectrograph gets high resolution of R=30,000 - 60,000 at a broad visible band from 370nm to 760nm. With the consideration about site seeing variation in future, single science fiber covers wider field on sky of 4.5arcsec instead of the present 3.3arcsec. An oversize Echelle R4 grating and a pre-slit image slicer are adopted to relieve the spectrograph resolution pressure. High resolution observation will parallel to the low resolution spectral survey at a small cost of losing a few fibers (10 - 20) on telescope focal plane. These science fibers will locate at the different sky areas for more approciate choice. The presentation will give the detailed design introduction and the current project status.

  1. A dried urine spot test to simultaneously monitor Mo and Ti levels using solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry

    NASA Astrophysics Data System (ADS)

    Rello, L.; Lapeña, A. C.; Aramendía, M.; Belarra, M. A.; Resano, M.

    2013-03-01

    Home-based collection protocols for clinical specimens are actively pursued as a means of improving life quality of patients that require frequent controls, such as patients with metallic prosthesis, for whom monitoring the evolution of Mo and Ti in biological fluids may play a decisive role to detect prosthesis mal-functioning. The collection of biological fluids on clinical filter papers provides a simple way to implement these protocols. This work explores the potential of solid sampling high-resolution continuum source graphite furnace atomic absorption spectrometry for the simultaneous and direct determination of Mo and Ti in urine, after its deposition onto clinical filter paper, giving rise to a dried urine spot. The approach used for depositing the sample was found crucial to develop a quantitative method, since the filter paper acts as a chromatographic support and produces a differential distribution of the target analytes. Furthermore, the high spreading of urine onto a filter paper results in a small amount of urine per surface unit, and thus, ultimately, in lack of sensitivity. In order to circumvent these problems, the use of an alternative approach based on the use of pre-cut 17 × 19 mm filter paper pieces onto which larger amounts of sample (500 μL) can be retained by single deposition was proposed and evaluated. In this way, an approximately 12-fold increase in sensitivity and a more homogeneous distribution of the target analytes were obtained, permitting the development of a quantification strategy based on the use of matrix-matched urine samples of known analyte concentrations, which were subjected to the same procedure as the samples. Accuracy of this method, which provides LODs of 1.5 μg L- 1 for Mo and 6.5 μg L- 1 for Ti, was demonstrated after analysis of urine reference materials. Overall, the performance of the method developed is promising, being likely suitable for determination of other analytes in dried urine spots.

  2. High resolution in-line analyses of precipitation at two UK ground locations, and possible relevance to convective cooling at cloud level.

    NASA Astrophysics Data System (ADS)

    Durham, Brian

    2015-04-01

    Wet deposition of many molecular pollutants can be simulated `sufficiently well' by a simple meteorological model, including the poorly soluble ozone (Tost et al, 2007, 2754). Carbon dioxide (CO2) has a Henry constant similar to that of ozone, but perhaps because its boundary layer presence is three orders of magnitude greater than ozone it has been widely assumed to be immune to significant cleansing by scavenging and deposition. In 2009 this `elephant' was approached (cautiously!) at the first of two UK locations using high time-resolution analyses of delivered rainwater, and some initial observations seem relevant to the `organised convection' theme of the present session. Six variables are measured every second, averaged every 60 seconds, including: conductivity; acidity ([H3O+] = 10 ^-pH ) and; stripped CO2 (by NDIRS). Convective precipitation typically delivers significantly more CO2 than predicted from Henry's Law, is supersaturated on arrival and shows a characteristic `spiky' profile against time. In assessing the above, this paper revisits eighty years of measurements of the Henry's Law equilibrium for the CO2/water system at partial pressures less than 1 atmosphere, and (more recently) low-pressure solubility at temperatures down to 4°C (Carroll, Slupski and Mather, 1991, 1203; Faraday Discuss. 2013, 167, 462-3). The observed solute load and supersaturation would become plausible if the reported upturn in solubility between 20°C and 4°C continued into the super-cooled zone. In a cloud, super-cooling will arise under convection when condensing droplets are chilled by adiabatic expansion of the carrier air. Droplets will increase in molar volume by up to 2.5% at -34°C (the temperature of spontaneous ice nucleation, Hare and Sorensen, 1987), offering a physical framework for the observed characteristics, and the possibility that `spikiness' reflects the degree of organisation of convection.

  3. NOAA's Use of High-Resolution Imagery

    NASA Technical Reports Server (NTRS)

    Hund, Erik

    2007-01-01

    NOAA's use of high-resolution imagery consists of: a) Shoreline mapping and nautical chart revision; b) Coastal land cover mapping; c) Benthic habitat mapping; d) Disaster response; and e) Imagery collection and support for coastal programs.

  4. High-Resolution Plots of Trigonometric Functions.

    ERIC Educational Resources Information Center

    Stick, Marvin E.; Stick, Michael J.

    1985-01-01

    Provides computer programs (for Apple microcomputers) for drawing (in high resolution graphics) a three-leaved rose, concentric circles, circumscribed and inscribed astroids. Sample output and discussions of the mathematics involved in the programs are included. (JN)

  5. High range resolution micro-Doppler analysis

    NASA Astrophysics Data System (ADS)

    Cammenga, Zachary A.; Smith, Graeme E.; Baker, Christopher J.

    2015-05-01

    This paper addresses use of the micro-Doppler effect and the use of high range-resolution profiles to observe complex targets in complex target scenes. The combination of micro-Doppler and high range-resolution provides the ability to separate the motion of complex targets from one another. This ability leads to the differentiation of targets based on their micro-Doppler signatures. Without the high-range resolution, this would not be possible because the individual signatures would not be separable. This paper also addresses the use of the micro-Doppler information and high range-resolution profiles to generate an approximation of the scattering properties of a complex target. This approximation gives insight into the structure of the complex target and, critically, is created without using a pre-determined target model.

  6. High-Resolution Radar Imagery of Mars

    NASA Astrophysics Data System (ADS)

    Harmon, John K.; Nolan, M. C.

    2009-09-01

    We present high-resolution radar images of Mars obtained during the 2005 and 2007 oppositions. The images were constructed from long-code delay-Doppler observations made with the Arecibo S-band (13-cm) radar. The average image resolution of 3 km represented a better than order-of-magnitude improvement over pre-upgrade Arecibo imagery of the planet. Images of depolarized reflectivity (an indicator primarily of wavelength-scale surface roughness) show the same bright volcanic flow features seen in earlier imagery, but with much finer detail. A new image of the Elysium region shows fine detail in the radar-bright channels of Athabasca Vallis, Marte Vallis, and Grjota Vallis. The new images of Tharsis and Olympus Mons also show a complex array of radar-bright and radar-dark features. Southern Amazonis exhibits some of the most complex and puzzling radar-bright structure on the planet. Another curiosity is the Chryse/Xanthe/Channels region, where we find some radar-bright features in or adjacent to fluvial chaos structures. Chryse/Xanthe is also the only region of Mars showing radar-bright craters (which are rare on Mars but common on the Moon and Mercury). We also obtained the first delay-Doppler image showing the enhanced backscatter from the residual south polar ice cap. In addition to the depolarized imagery, we were able to make the first delay-Doppler images of the circular polarization ratio (an important diagnostic for surface roughness texture). We find that vast areas of the radar-bright volcanic regions have polarization ratios close to unity. Such high ratios are rare for terrestrial lava flows and only seen for extremely blocky surfaces giving high levels of multiple scattering.

  7. High resolution quantum metrology via quantum interpolation

    NASA Astrophysics Data System (ADS)

    Ajoy, Ashok; Liu, Yixiang; Saha, Kasturi; Marseglia, Luca; Jaskula, Jean-Christophe; Cappellaro, Paola

    2016-05-01

    Nitrogen Vacancy (NV) centers in diamond are a promising platform for quantum metrology - in particular for nanoscale magnetic resonance imaging to determine high resolution structures of single molecules placed outside the diamond. The conventional technique for sensing of external nuclear spins involves monitoring the effects of the target nuclear spins on the NV center coherence under dynamical decoupling (the CPMG/XY8 pulse sequence). However, the nuclear spin affects the NV coherence only at precise free evolution times - and finite timing resolution set by hardware often severely limits the sensitivity and resolution of the method. In this work, we overcome this timing resolution barrier by developing a technique to supersample the metrology signal by effectively implementing a quantum interpolation of the spin system dynamics. This method will enable spin sensing at high magnetic fields and high repetition rate, allowing significant improvements in sensitivity and spectral resolution. We experimentally demonstrate a resolution boost by over a factor of 100 for spin sensing and AC magnetometry. The method is shown to be robust, versatile to sensing normal and spurious signal harmonics, and ultimately limited in resolution only by the number of pulses that can be applied.

  8. High-energy resolution, high-angular acceptance crystal monochromator

    SciTech Connect

    Toellner, T.S.; Mooney, T.; Alp, E.E.; Shastri, S.

    1992-06-01

    The design principles, construction and characterization of a 4- bounce dispersive crystal monochromator is discussed. This monochromator is designed to reduce the bandpass of synchrotron radiation to 10--50 meV level, without sacrificing angular acceptance. This is achieved by combining an asymmetrically-cut, low order reflection with a symmetrically-cut, high order reflection in a nested configuration. This monochromator is being used as a beam conditioner for nuclear resonant scattering of synchrotron radiation to produce x-rays with {mu}eV{minus}neV resolution in the hard x-ray regime.

  9. High-energy resolution, high-angular acceptance crystal monochromator

    SciTech Connect

    Toellner, T.S.; Mooney, T.; Alp, E.E. ); Shastri, S. . Dept. of Applied Physics)

    1992-06-01

    The design principles, construction and characterization of a 4- bounce dispersive crystal monochromator is discussed. This monochromator is designed to reduce the bandpass of synchrotron radiation to 10--50 meV level, without sacrificing angular acceptance. This is achieved by combining an asymmetrically-cut, low order reflection with a symmetrically-cut, high order reflection in a nested configuration. This monochromator is being used as a beam conditioner for nuclear resonant scattering of synchrotron radiation to produce x-rays with [mu]eV[minus]neV resolution in the hard x-ray regime.

  10. High resolution SAR applications and instrument design

    NASA Technical Reports Server (NTRS)

    Dionisio, C.; Torre, A.

    1993-01-01

    The Synthetic Aperture Radar (SAR) has viewed, in the last two years, a huge increment of interest from many preset and potential users. The good spatial resolution associated to the all weather capability lead to considering SAR not only a scientific instrument but a tool for verifying and controlling the daily human relationships with the Earth Environment. New missions were identified for SAR as spatial resolution became lower than three meters: disasters, pollution, ships traffic, volcanic eruptions, earthquake effect are only a few of the possible objects which can be effectively detected, controlled and monitored by SAR mounted on satellites. High resolution radar design constraints and dimensioning are discussed.

  11. Invariant high resolution optical skin imaging

    NASA Astrophysics Data System (ADS)

    Murali, Supraja; Rolland, Jannick

    2007-02-01

    Optical Coherence Microscopy (OCM) is a bio-medical low coherence interferometric imaging technique that has become a topic of active research because of its ability to provide accurate, non-invasive cross-sectional images of biological tissue with much greater resolution than the current common technique ultrasound. OCM is a derivative of Optical Coherence Tomography (OCT) that enables greater resolution imposed by the implementation of an optical confocal design involving high numerical aperture (NA) focusing in the sample. The primary setback of OCM, however is the depth dependence of the lateral resolution obtained that arises from the smaller depth of focus of the high NA beam. We propose to overcome this limitation using a dynamic focusing lens design that can achieve quasi-invariant lateral resolution up to 1.5mm depth of skin tissue.

  12. Relative utility of foraminifera, diatoms and macrophytes as high resolution indicators of paleo-sea level in coastal British Columbia, Canada

    NASA Astrophysics Data System (ADS)

    Patterson, R. Timothy; Dalby, Andrew P.; Roe, Helen M.; Guilbault, Jean-Pierre; Hutchinson, Ian; Clague, John J.

    2005-10-01

    A multiproxy analysis was carried out on diatom, foraminiferal and macrophyte assemblages across the saltmarsh at Zeballos, Vancouver Island, British Columbia. To determine which group, or combination of groups provided the most accurate elevational zonations, 36 stepwise multiple linear regressions (SMLR) were carried out using a variety of data transformations on an elevational training set. Adjusted R2 values yielded statistically significant results in all analyses as follows: foraminifera (0.658-0.870); diatoms (0.888-0.974); macrophytes (0.671-0.844); foraminifera/diatoms (0.941-0.981); foraminifera/diatoms/macrophytes (0.958-0.993). The most realistic SMLR results were obtained when data transformations comprised of (ln) normalized fractional abundance data was carried out on species present in statistically significant numbers (NrfaEQ). Of the individual proxies assessed, diatoms yielded the most significant adjusted R2 results, with the low marsh diatom Achnanthes hauckiana being one of the most important predictor variables (pv's). Amongst the foraminifera, the low marsh species Miliammina fusca and high marsh Balticammina pseudomacrescens were determined to be the most significant pv's. For macrophytes, the low marsh species Carex lyngbyei, the high marsh species Juncus balticus, Shannon-Wiener Diversity Index (SDI) and absence of plant cover on the tidal flat were the most important pv's. As SMLR analysis of all individual groups and combinations of groups yielded statistically significant results, the choice of proxies, or combinations of proxies that are suitable for paleo-sea level research is at the discretion of the researcher.

  13. High spectral resolution reflectance spectroscopy of minerals

    USGS Publications Warehouse

    Clark, R.N.; King, T.V.V.; Klejwa, M.; Swayze, G.A.; Vergo, N.

    1990-01-01

    The reflectance spectra of minerals are studied as a function of spectral resolution in the range from 0.2 to 3.0 ??m. Selected absorption bands were studied at resolving powers (??/????) as high as 2240. At resolving powers of approximately 1000, many OH-bearing minerals show diagnostic sharp absorptions at the resolution limit. At low resolution, some minerals may not be distinguishable, but as the resolution is increased, most can be easily identified. As the resolution is increased, many minerals show fine structure, particularly in the OH-stretching overtone region near 1.4 ??m. The fine structure can enhance the ability to discriminate between minerals, and in some cases the fine structure can be used to determine elemental composition. The study shows that high-resolution reflectance spectroscopy of minerals may prove to be a very important tool in the laboratory, in the field using field-portable spectrometers, from aircraft, and from satellites looking at Earth or other planetary surfaces. -from Authors

  14. High resolution solar X-ray studies

    NASA Technical Reports Server (NTRS)

    Blake, R. L.

    1974-01-01

    Two high resolution solar X-ray payloads and their launches on Aerobee rockets with pointing system are described. The payloads included 5 to 25A X-ray spectrometers, multiaperture X-ray cameras, and command box attitude control inflight by means of a television image radioed to ground. Spatial resolution ranged from five arc minutes to ten arc seconds and spectral resolution ranged from 500 to 3000. Several laboratory tasks were completed in order to achieve the desired resolution. These included (1) development of techniques to align grid collimators, (2) studies of the spectrometric properties of crystals, (3) measurements of the absorption coefficients of various materials used in X-ray spectrometers, (4) evaluation of the performance of multiaperture cameras, and (5) development of facilities.

  15. Solar system events at high spatial resolution

    SciTech Connect

    Baines, K H; Gavel, D T; Getz, A M; Gibbartd, S G; MacIntosh, B; Max, C E; McKay, C P; Young, E F; de Pater, I

    1999-02-19

    Until relatively recent advances in technology, astronomical observations from the ground were limited in image resolution by the blurring effects of earth's atmosphere. The blur extent, ranging typically from 0.5 to 2 seconds of arc at the best astronomical sights, precluded ground-based observations of the details of the solar system's moons, asteroids, and outermost planets. With the maturing of a high resolution image processing technique called speckle imaging the resolution limitation of the atmosphere can now be largely overcome. Over the past three years they have used speckle imaging to observe Titan, a moon of Saturn with an atmospheric density comparable to Earth's, Io, the volcanically active innermost moon of Jupiter, and Neptune, a gas giant outer planet which has continually changing planet-encircling storms. These observations were made at the world's largest telescope, the Keck telescope in Hawaii and represent the highest resolution infrared images of these objects ever taken.

  16. High-Resolution PET Detector. Final report

    SciTech Connect

    Karp, Joel

    2014-03-26

    The objective of this project was to develop an understanding of the limits of performance for a high resolution PET detector using an approach based on continuous scintillation crystals rather than pixelated crystals. The overall goal was to design a high-resolution detector, which requires both high spatial resolution and high sensitivity for 511 keV gammas. Continuous scintillation detectors (Anger cameras) have been used extensively for both single-photon and PET scanners, however, these instruments were based on NaI(Tl) scintillators using relatively large, individual photo-multipliers. In this project we investigated the potential of this type of detector technology to achieve higher spatial resolution through the use of improved scintillator materials and photo-sensors, and modification of the detector surface to optimize the light response function.We achieved an average spatial resolution of 3-mm for a 25-mm thick, LYSO continuous detector using a maximum likelihood position algorithm and shallow slots cut into the entrance surface.

  17. High Spatial Resolution Thermal Satellite Technologies

    NASA Technical Reports Server (NTRS)

    Ryan, Robert

    2003-01-01

    This document in the form of viewslides, reviews various low-cost alternatives to high spatial resolution thermal satellite technologies. There exists no follow-on to Landsat 7 or ASTER high spatial resolution thermal systems. This document reviews the results of the investigation in to the use of new technologies to create a low-cost useful alternative. Three suggested technologies are examined. 1. Conventional microbolometer pushbroom modes offers potential for low cost Landsat Data Continuity Mission (LDCM) thermal or ASTER capability with at least 60-120 ground sampling distance (GSD). 2. Backscanning could produce MultiSpectral Thermal Imager performance without cooled detectors. 3. Cooled detector could produce hyperspectral thermal class system or extremely high spatial resolution class instrument.

  18. A High Resolution Scale-of-four

    DOE R&D Accomplishments Database

    Fitch, V.

    1949-08-25

    A high resolution scale-of-four has been developed to be used in conjunction with the nuclear particle detection devices in applications where the counting rate is unusually high. Specifically, it is intended to precede the commercially available medium resolution scaling circuits and so decrease the resolving time of the counting system. The circuit will function reliably on continuously recurring pulses separated by less than 0.1 microseconds. It will resolve two pulses (occurring at a moderate repetition rate) which are spaced at 0.04 microseconds. A five-volt input signal is sufficient to actuate the device.

  19. High-resolution scanning hall probe microscopy

    NASA Astrophysics Data System (ADS)

    Hicks, Clifford; Luan, Lan; Hendrik Bluhm, J.; Moler, Kathryn; Guikema, Janice; Zeldov, Eli; Shtrikman, Hadas

    2006-03-01

    Scanning hall sensors can be used to directly image magnetic fields at surfaces. They offer high resolution, high sensitivity, operability over a broad temperature range, and linearity. We have fabricated hall sensors on GaAs / Al0.35Ga0.65As and GaAs / Al0.3Ga0.7As heterostructures containing 2D electron gases 40, 39 and 140nm beneath the surface. The sensitive areas of our probes range from microns to 85nm on a side. We report on the field sensitivities of probes of various sizes and their spatial resolution in a scanning configuration.

  20. ELECTRONICS UPGRADE OF HIGH RESOLUTION MASS SPECTROMETERS

    SciTech Connect

    Mcintosh, J; Joe Cordaro, J

    2008-03-10

    High resolution mass spectrometers are specialized systems that allow researchers to determine the exact mass of samples to four significant digits by using magnetic and electronic sector mass analyzers. Many of the systems in use today at research laboratories and universities were designed and built more than two decades ago. The manufacturers of these systems have abandoned the support for some of the mass spectrometers and parts to power and control them have become scarce or obsolete. The Savannah River National Laboratory has been involved in the upgrade of the electronics and software for these legacy machines. The Electronics Upgrade of High Resolution Mass Spectrometers consists of assembling high-end commercial instrumentation from reputable manufacturers with a minimal amount of customization to replace the electronics for the older systems. By taking advantage of advances in instrumentation, precise magnet control can be achieved using high resolution current sources and continuous feedback from a high resolution hall-effect probe. The custom equipment include a precision voltage divider/summing amplifier chassis, high voltage power supply chassis and a chassis for controlling the voltage emission for the mass spectrometer source tube. The upgrade package is versatile enough to interface with valve control, vacuum and other instrumentation. Instrument communication is via a combination of Ethernet and traditional IEEE-488 GPIB protocols. The system software upgrades include precision control, feedback and spectral waveform analysis tools.

  1. Customized MFM probes with high lateral resolution

    PubMed Central

    Jaafar, Miriam; Berganza, Eider; Asenjo, Agustina

    2016-01-01

    Summary Magnetic force microscopy (MFM) is a widely used technique for magnetic imaging. Besides its advantages such as the high spatial resolution and the easy use in the characterization of relevant applied materials, the main handicaps of the technique are the lack of control over the tip stray field and poor lateral resolution when working under standard conditions. In this work, we present a convenient route to prepare high-performance MFM probes with sub-10 nm (sub-25 nm) topographic (magnetic) lateral resolution by following an easy and quick low-cost approach. This allows one to not only customize the tip stray field, avoiding tip-induced changes in the sample magnetization, but also to optimize MFM imaging in vacuum (or liquid media) by choosing tips mounted on hard (or soft) cantilevers, a technology that is currently not available on the market. PMID:27547625

  2. Customized MFM probes with high lateral resolution.

    PubMed

    Iglesias-Freire, Óscar; Jaafar, Miriam; Berganza, Eider; Asenjo, Agustina

    2016-01-01

    Magnetic force microscopy (MFM) is a widely used technique for magnetic imaging. Besides its advantages such as the high spatial resolution and the easy use in the characterization of relevant applied materials, the main handicaps of the technique are the lack of control over the tip stray field and poor lateral resolution when working under standard conditions. In this work, we present a convenient route to prepare high-performance MFM probes with sub-10 nm (sub-25 nm) topographic (magnetic) lateral resolution by following an easy and quick low-cost approach. This allows one to not only customize the tip stray field, avoiding tip-induced changes in the sample magnetization, but also to optimize MFM imaging in vacuum (or liquid media) by choosing tips mounted on hard (or soft) cantilevers, a technology that is currently not available on the market. PMID:27547625

  3. Intracellular membrane traffic at high resolution

    PubMed Central

    van Weering, Jan R.T.; Brown, Edward; Sharp, Thomas H.; Mantell, Judith; Cullen, Peter J.

    2014-01-01

    I. Abstract Membrane traffic between organelles is essential for a multitude of processes that maintain cell homeostasis. Many steps in these tightly regulated trafficking pathways take place in microdomains on the membranes of organelles, which require analysis at nanometer resolution. Electron Microscopy (EM) can visualize these processes in detail and is mainly responsible for our current view of morphology on the subcellular level. This review discusses how EM can be applied to solve many questions of intracellular membrane traffic, with a focus on the endosomal system. We describe the expansion of the technique from purely morphological analysis to cryo-immuno-EM, Correlative Light Electron Microscopy (CLEM) and 3D electron tomography. In this review we go into some technical details of these various techniques. Furthermore, we provide a full protocol for immunolabeling on Lowicryl sections of high-pressure frozen cells as well as a detailed description of a simple CLEM method that can be applied to answer many membrane trafficking questions. We believe that these EM-based techniques are important tools to expand our understanding of the molecular details of endosomal sorting and intracellular membrane traffic in general. PMID:20869541

  4. Holographic high-resolution endoscopic image recording

    NASA Astrophysics Data System (ADS)

    Bjelkhagen, Hans I.

    1991-03-01

    Endoscopic holography or endoholography combines the features of endoscopy and holography. The purpose of endoholographic imaging is to provide the physician with a unique means of extending diagnosis by providing a life-like record of tissue. Endoholographic recording will provide means for microscopic examination of tissue and in some cases may obviate the need to excise specimens for biopsy. In this method holograms which have the unique properties of three-dimensionality large focal depth and high resolution are made with a newly designed endoscope. The endoscope uses a single-mode optical fiber for illumination and single-beam reflection holograms are recorded in close contact with the tissue at the distal end of the endoscope. The holograms are viewed under a microscope. By using the proper combinations of dyes for staining specific tissue types with various wavelengths of laser illumination increased contrast on the cellular level can be obtained. Using dyes such as rose bengal in combination with the 514. 5 nm line of an argon ion laser and trypan blue or methylene blue with the 647. 1 nm line of a krypton ion laser holograms of the stained colon of a dog showed the architecture of the colon''s columnar epithelial cells. It is hoped through chronological study using this method in-vivo an increased understanding of the etiology and pathology of diseases such as Crohn''s diseases colitis proctitis and several different forms of cancer will help

  5. High-resolution imaging using endoscopic holography

    NASA Astrophysics Data System (ADS)

    Bjelkhagen, Hans I.

    1990-08-01

    Endoscopic holography or endoholography combines the features of endoscopy and holography. The purpose of endoholographic imaging is to provide the physician with a unique means of extending diagnosis by providing a life-like record of tissue. Endoholographic recording will provide means for microscopic examination of tissue and in some cases may obviate the need to excise specimens for biopsy. In this method holograms which have the unique properties of three-dimensionality large focal depth and high resolution are made with a newly designed endoscope. The endoscope uses a single-mode optical fiber for illumination and single-beam reflection holograms are recorded in close contact with the tissue at the distal end of the endoscope. The holograms are viewed under a microscope. By using the proper combinations of dyes for staining specific tissue types with various wavelengths of laser illumination increased contrast on the cellular level can be obtained. Using dyes such as rose bengal in combination with the 514. 5 nm line of an argon ion laser and trypan blue or methylene blue with the 647. 1 nm line of a krypton ion laser holograms of the stained colon of a dog showed the architecture of the colon''s columnar epithelial cells. It is hoped through chronological study using this method in-vivo an increased understanding of the etiology and pathology of diseases such as Crohn''s diseases colitis proctitis and several different forms of cancer will help to their control. 1.

  6. A case study of the Great Plains low-level jet using wind profiler network data and a high resolution mesoscale model

    SciTech Connect

    Zhong, S.; Fast, J.D.; Bian, X.; Stage, S.

    1996-04-01

    The Great Plains low-level jet (LLJ) has important effects on the life cycle of clouds and on radiative and surface heat and moisture fluxes at the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site. This diurnal phenomenon governs the transport and convergence of low-level moisture into the region and often leads to the development of clouds and precipitation. A full understanding of the life cycle of clouds at the SGP CART site and their proper representation in single column and global climate models cannot be obtained without an improved understanding of this important phenomenon.

  7. High-resolution x-ray telescopes

    NASA Astrophysics Data System (ADS)

    O'Dell, Stephen L.; Brissenden, Roger J.; Davis, William N.; Elsner, Ronald F.; Elvis, Martin S.; Freeman, Mark D.; Gaetz, Terrance; Gorenstein, Paul; Gubarev, Mikhail V.; Jerius, Diab; Juda, Michael; Kolodziejczak, Jeffery J.; Murray, Stephen S.; Petre, Robert; Podgorski, William; Ramsey, Brian D.; Reid, Paul B.; Saha, Timo; Schwartz, Daniel A.; Trolier-McKinstry, Susan; Weisskopf, Martin C.; Wilke, Rudeger H. T.; Wolk, Scott; Zhang, William W.

    2010-08-01

    High-energy astrophysics is a relatively young scientific field, made possible by space-borne telescopes. During the half-century history of x-ray astronomy, the sensitivity of focusing x-ray telescopes-through finer angular resolution and increased effective area-has improved by a factor of a 100 million. This technological advance has enabled numerous exciting discoveries and increasingly detailed study of the high-energy universe-including accreting (stellarmass and super-massive) black holes, accreting and isolated neutron stars, pulsar-wind nebulae, shocked plasma in supernova remnants, and hot thermal plasma in clusters of galaxies. As the largest structures in the universe, galaxy clusters constitute a unique laboratory for measuring the gravitational effects of dark matter and of dark energy. Here, we review the history of high-resolution x-ray telescopes and highlight some of the scientific results enabled by these telescopes. Next, we describe the planned next-generation x-ray-astronomy facility-the International X-ray Observatory (IXO). We conclude with an overview of a concept for the next next-generation facility-Generation X. The scientific objectives of such a mission will require very large areas (about 10000 m2) of highly-nested lightweight grazing-incidence mirrors with exceptional (about 0.1-arcsecond) angular resolution. Achieving this angular resolution with lightweight mirrors will likely require on-orbit adjustment of alignment and figure.

  8. A High-Resolution Stopwatch for Cents

    ERIC Educational Resources Information Center

    Gingl, Z.; Kopasz, K.

    2011-01-01

    A very low-cost, easy-to-make stopwatch is presented to support various experiments in mechanics. The high-resolution stopwatch is based on two photodetectors connected directly to the microphone input of a sound card. Dedicated free open-source software has been developed and made available to download. The efficiency is demonstrated by a free…

  9. Nuke-sparing regimens as a main simplification strategy and high level of toxicity resolution after antiretroviral switch: the SWITCHART Study

    PubMed Central

    Carrero-Gras, Ana; Antela, Antonio; Muñoz-Rodríguez, Jessica; Díaz-Menéndez, Marta; Viciana, Pompeyo; Torrella-Domingo, Adriadna; Sanz-Moreno, José; Jesús Téllez-Molina, María; Moreno, Javier; Hernández-Quero, José; Pérez-Hernández, Isabel A; Domingo-Pedrol, Pere

    2014-01-01

    in most cases this drug was removed from the new regimen (with 3TC/ABC or nuke-sparing). Among patients with CNS toxicity, 79% were taking EFV; the main new treatment was a second-generation NNRTI (ETR)+2NRTI. Toxicities were completely resolved in 66% of patients, partially resolved in 22% and not resolved in only 12%; the median time from ART switch to toxicity resolution was 4 (2–8) months. Conclusions The main reasons for ART switch in daily practice are simplification and toxicities, renal and CNS toxicities being the most prevalent. The preferred simplification strategies are nuke-sparing regimens, mainly DRV/r-based monotherapy and dual therapy. ART switch leads to a complete resolution of toxicities in most cases in the short term. PMID:25397563

  10. High Resolution Sapphire Bragg Backscattering Monochromator

    SciTech Connect

    Linden, P. van der; Wille, H.-C.; Shvyd'ko, Yu. V.

    2007-01-19

    We present a temperature stabilised high resolution sapphire backscattering monochromator. The device consists of a sapphire crystal inside a cold nitrogen gas cooled, temperature stabilised chamber with a passively temperature stabilised screen. The achieved temperature stability of {+-}2mK allows for an energy resolution of {delta}E/E {<=} 10-7 at energies in the range of 30-70 keV. The device was developed for nuclear resonant scattering above 30 keV, where appropriate solutions did not exist until now.

  11. A Portable, High Resolution, Surface Measurement Device

    NASA Technical Reports Server (NTRS)

    Ihlefeld, Curtis M.; Burns, Bradley M.; Youngquist, Robert C.

    2012-01-01

    A high resolution, portable, surface measurement device has been demonstrated to provide micron-resolution topographical plots. This device was specifically developed to allow in-situ measurements of defects on the Space Shuttle Orbiter windows, but is versatile enough to be used on a wide variety of surfaces. This paper discusses the choice of an optical sensor and then the decisions required to convert a lab bench optical measurement device into an ergonomic portable system. The necessary trade-offs between performance and portability are presented along with a description of the device developed to measure Orbiter window defects.

  12. A Novel 2D Image Compression Algorithm Based on Two Levels DWT and DCT Transforms with Enhanced Minimize-Matrix-Size Algorithm for High Resolution Structured Light 3D Surface Reconstruction

    NASA Astrophysics Data System (ADS)

    Siddeq, M. M.; Rodrigues, M. A.

    2015-09-01

    Image compression techniques are widely used on 2D image 2D video 3D images and 3D video. There are many types of compression techniques and among the most popular are JPEG and JPEG2000. In this research, we introduce a new compression method based on applying a two level discrete cosine transform (DCT) and a two level discrete wavelet transform (DWT) in connection with novel compression steps for high-resolution images. The proposed image compression algorithm consists of four steps. (1) Transform an image by a two level DWT followed by a DCT to produce two matrices: DC- and AC-Matrix, or low and high frequency matrix, respectively, (2) apply a second level DCT on the DC-Matrix to generate two arrays, namely nonzero-array and zero-array, (3) apply the Minimize-Matrix-Size algorithm to the AC-Matrix and to the other high-frequencies generated by the second level DWT, (4) apply arithmetic coding to the output of previous steps. A novel decompression algorithm, Fast-Match-Search algorithm (FMS), is used to reconstruct all high-frequency matrices. The FMS-algorithm computes all compressed data probabilities by using a table of data, and then using a binary search algorithm for finding decompressed data inside the table. Thereafter, all decoded DC-values with the decoded AC-coefficients are combined in one matrix followed by inverse two levels DCT with two levels DWT. The technique is tested by compression and reconstruction of 3D surface patches. Additionally, this technique is compared with JPEG and JPEG2000 algorithm through 2D and 3D root-mean-square-error following reconstruction. The results demonstrate that the proposed compression method has better visual properties than JPEG and JPEG2000 and is able to more accurately reconstruct surface patches in 3D.

  13. High resolution schemes for hyperbolic conservation laws

    NASA Technical Reports Server (NTRS)

    Harten, A.

    1983-01-01

    A class of new explicit second order accurate finite difference schemes for the computation of weak solutions of hyperbolic conservation laws is presented. These highly nonlinear schemes are obtained by applying a nonoscillatory first order accurate scheme to an appropriately modified flux function. The so-derived second order accurate schemes achieve high resolution while preserving the robustness of the original nonoscillatory first order accurate scheme. Numerical experiments are presented to demonstrate the performance of these new schemes.

  14. High resolution imaging of boron carbide microstructures

    SciTech Connect

    Mackinnon, I.D.R.; Aselage, T.; Van Deusen, S.B.

    1985-08-01

    Two samples of boron carbide have been examined using high resolution transmission electron microscopy (HRTEM). A hot-pressed B/sub 13/C/sub 2/ sample shows a high density of variable width twins normal to (10*1). Subtle shifts or offsets of lattice fringes along the twin plane and normal to approx.(10*5) were also observed. A B/sub 4/C powder showed little evidence of stacking disorder in crystalline regions.

  15. High resolution imaging of boron carbide microstructures

    SciTech Connect

    MacKinnon, I.D.R.; Aselage, T.; Van Deusen, S.B.

    1986-04-15

    Two samples of boron carbide have been examined using high resolution transmission electron microscopy (HRTEM). A hot-pressed B/sub 13/C/sub 2/ sample shows a high density of variable width twins normal to (10*1). Subtle shifts or offsets of lattice fringes along the twin plane and normal to approx.(10*5) were also observed. A B/sub 4/C powder showed little evidence of stacking disorder in crystalline regions.

  16. High-Resolution Traction Force Microscopy

    PubMed Central

    Plotnikov, Sergey V.; Sabass, Benedikt; Schwarz, Ulrich S.; Waterman, Clare M.

    2015-01-01

    Cellular forces generated by the actomyosin cytoskeleton and transmitted to the extracellular matrix (ECM) through discrete, integrin-based protein assemblies, that is, focal adhesions, are critical to developmental morphogenesis and tissue homeostasis, as well as disease progression in cancer. However, quantitative mapping of these forces has been difficult since there has been no experimental technique to visualize nanonewton forces at submicrometer spatial resolution. Here, we provide detailed protocols for measuring cellular forces exerted on two-dimensional elastic substrates with a high-resolution traction force microscopy (TFM) method. We describe fabrication of polyacrylamide substrates labeled with multiple colors of fiducial markers, functionalization of the substrates with ECM proteins, setting up the experiment, and imaging procedures. In addition, we provide the theoretical background of traction reconstruction and experimental considerations important to design a high-resolution TFM experiment. We describe the implementation of a new algorithm for processing of images of fiducial markers that are taken below the surface of the substrate, which significantly improves data quality. We demonstrate the application of the algorithm and explain how to choose a regularization parameter for suppression of the measurement error. A brief discussion of different ways to visualize and analyze the results serves to illustrate possible uses of high-resolution TFM in biomedical research. PMID:24974038

  17. High resolution electron crystallography of protein molecules

    SciTech Connect

    Glaeser, R.M. |; Downing, K.H.

    1993-06-01

    Electron diffraction data and high resolution images can now be used to obtain accurate, three-dimensional density maps of biological macromolecules. These density maps can be interpreted by building an atomic-resolution model of the structure into the experimental density. The Cowley-Moodie formalism of dynamical diffraction theory has been used to validate the use of kinematic diffraction theory, strictly the weak phase object approximation, in producing such 3-D density maps. Further improvements in the preparation of very flat specimens and in the retention of diffraction to a resolution of 0.2 nm or better could result in electron crystallography becoming as important a technique as x-ray crystallography currently is for the field of structural molecular biology.

  18. Constructing a WISE High Resolution Galaxy Atlas

    NASA Technical Reports Server (NTRS)

    Jarrett, T. H.; Masci, F.; Tsai, C. W.; Petty, S.; Cluver, M.; Assef, Roberto J.; Benford, D.; Blain, A.; Bridge, C.; Donoso, E.; Eisenhardt, P.; Fowler, J.; Koribalski, B.; Lake, S.; Neill, James D.; Seibert, M.; Stanford, S.; Wright, E.

    2012-01-01

    After eight months of continuous observations, the Wide-field Infrared Survey Explorer (WISE) mapped the entire sky at 3.4 micron, 4.6 micron, 12 micron, and 22 micron. We have begun a dedicated WISE High Resolution Galaxy Atlas project to fully characterize large, nearby galaxies and produce a legacy image atlas and source catalog. Here we summarize the deconvolution techniques used to significantly improve the spatial resolution of WISE imaging, specifically designed to study the internal anatomy of nearby galaxies. As a case study, we present results for the galaxy NGC 1566, comparing the WISE enhanced-resolution image processing to that of Spitzer, Galaxy Evolution Explorer, and ground-based imaging. This is the first paper in a two-part series; results for a larger sample of nearby galaxies are presented in the second paper.

  19. High Resolution Local Structure-Constrained Image Upsampling.

    PubMed

    Zhao, Yang; Wang, Ronggang; Wang, Wenmin; Gao, Wen

    2015-11-01

    With the development of ultra-high-resolution display devices, the visual perception of fine texture details is becoming more and more important. A method of high-quality image upsampling with a low cost is greatly needed. In this paper, we propose a fast and efficient image upsampling method that makes use of high-resolution local structure constraints. The average local difference is used to divide a bicubic-interpolated image into a sharp edge area and a texture area, and these two areas are reconstructed separately with specific constraints. For reconstruction of the sharp edge area, a high-resolution gradient map is estimated as an extra constraint for the recovery of sharp and natural edges; for the reconstruction of the texture area, a high-resolution local texture structure map is estimated as an extra constraint to recover fine texture details. These two reconstructed areas are then combined to obtain the final high-resolution image. The experimental results demonstrated that the proposed method recovered finer pixel-level texture details and obtained top-level objective performance with a low time cost compared with state-of-the-art methods. PMID:26186777

  20. High Resolution Laser Spectroscopy for Absorption to Levels Lying Near the Dissociation Limit of the a ^3Π_1 State of {IBr}

    NASA Astrophysics Data System (ADS)

    Yukiya, Tokio; Nishimiya, Nobuo; Suzuki, Masao; Le Roy, Robert J.

    2015-06-01

    Spectroscopic data involving levels lying near the dissociation limit are very important for determining accurate molecular well depths and full potential energy curves. In previous work, we have reported the potential functions and values of parameters D_e and r_e for the A ^3Π_1 and X ^1σ^+ states of IBr. That study used data extending to v'(A)=29 and determined anomalous fluctuations in the v--dependence of the first differences of Δ Bv=Bv+1-Bv for levels v'=27-29 of the A ^3Π_1 state which, surprisingly, seems to have been smoothly accounted by a fitted potential energy function that shows no visually perceptible irregularities. In the present work, a Ti:Sapphire ring laser(M SQUARED LASERS Ltd. SolsTiS CW with Tera--scan) has been introduced to probe the 0.7μm region closer to the dissociation limit and examine whether the anomalous Δ Bv behaviour expends further up the well. The results of this study will be presented. T.Yukiya, N. Nishimiya, M. Suzuki and R.J. Le Roy, paper MG03 at the 69th International Symposium on Molecular Spectroscopy, University of Illinois (2014)

  1. High resolution 3D nonlinear integrated inversion

    NASA Astrophysics Data System (ADS)

    Li, Yong; Wang, Xuben; Li, Zhirong; Li, Qiong; Li, Zhengwen

    2009-06-01

    The high resolution 3D nonlinear integrated inversion method is based on nonlinear theory. Under layer control, the log data from several wells (or all wells) in the study area and seismic trace data adjacent to the wells are input to a network with multiple inputs and outputs and are integratedly trained to obtain an adaptive weight function of the entire study area. Integrated nonlinear mapping relationships are built and updated by the lateral and vertical geologic variations of the reservoirs. Therefore, the inversion process and its inversion results can be constrained and controlled and a stable seismic inversion section with high resolution with velocity inversion, impedance inversion, and density inversion sections, can be gained. Good geologic effects have been obtained in model computation tests and real data processing, which verified that this method has high precision, good practicality, and can be used for quantitative reservoir analysis.

  2. Superconducting High Resolution Fast-Neutron Spectrometers

    SciTech Connect

    Hau, I D

    2006-05-25

    Superconducting high resolution fast-neutron calorimetric spectrometers based on {sup 6}LiF and TiB{sub 2} absorbers have been developed. These novel cryogenic spectrometers measure the temperature rise produced in exothermal (n, {alpha}) reactions with fast neutrons in {sup 6}Li and {sup 10}B-loaded materials with heat capacity C operating at temperatures T close to 0.1 K. Temperature variations on the order of 0.5 mK are measured with a Mo/Cu thin film multilayer operated in the transition region between its superconducting and its normal state. The advantage of calorimetry for high resolution spectroscopy is due to the small phonon excitation energies k{sub B}T on the order of {mu}eV that serve as signal carriers, resulting in an energy resolution {Delta}E {approx} (k{sub B}T{sup 2}C){sup 1/2}, which can be well below 10 keV. An energy resolution of 5.5 keV has been obtained with a Mo/Cu superconducting sensor and a TiB{sub 2} absorber using thermal neutrons from a {sup 252}Cf neutron source. This resolution is sufficient to observe the effect of recoil nuclei broadening in neutron spectra, which has been related to the lifetime of the first excited state in {sup 7}Li. Fast-neutron spectra obtained with a {sup 6}Li-enriched LiF absorber show an energy resolution of 16 keV FWHM, and a response in agreement with the {sup 6}Li(n, {alpha}){sup 3}H reaction cross section and Monte Carlo simulations for energies up to several MeV. The energy resolution of order of a few keV makes this novel instrument applicable to fast-neutron transmission spectroscopy based on the unique elemental signature provided by the neutron absorption and scattering resonances. The optimization of the energy resolution based on analytical and numerical models of the detector response is discussed in the context of these applications.

  3. DKIST: Observing the Sun at High Resolution

    NASA Astrophysics Data System (ADS)

    Tritschler, A.; Rimmele, T. R.; Berukoff, S.; Casini, R.; Craig, S. C.; Elmore, D. F.; Hubbard, R. P.; Kuhn, J. R.; Lin, H.; McMullin, J. P.; Reardon, K. P.; Schmidt, W.; Warner, M.; Woger, F.

    2015-01-01

    The 4-m aperture Daniel K. Inouye Solar Telescope (DKIST) formerly known as the Advanced Technology Solar Telescope (ATST) and currently under construction on Haleakalā (Maui, Hawai'i) will be the largest solar ground-based telescope and leading resource for studying the dynamic Sun and its phenomena at high spatial, spectral and temporal resolution. Accurate and sensitive polarimetric observations at high-spatial resolution throughout the solar atmosphere including the corona is a high priority and a major science driver. As such the DKIST will offer a combination of state-of-the-art instruments with imaging and/or spectropolarimetric capabilities covering a broad wavelength range. This first-light instrumentation suite will include: a Visible Broadband Imager (VBI) for high-spatial and -temporal resolution imaging of the solar atmosphere; a Visible Spectro-Polarimeter (ViSP) for sensitive and accurate multi-line spectropolarimetry; a double Fabry-Pérot based Visible Tunable Filter (VTF) for high-spatial resolution spectropolarimetry; a fiber-fed 2D Diffraction-Limited Near Infra-Red Spectro-Polarimeter (DL-NIRSP); and a Cryogenic Near Infra-Red Spectro-Polarimeter (Cryo-NIRSP) for coronal magnetic field measurements and on-disk observations of e.g. the CO lines at 4.7 microns. We will provide a brief overview of the DKIST's unique capabilities to perform spectroscopic and spectropolarimetric measurements of the solar atmosphere using its first-light instrumentation suite, the status of the construction project, and how facility and data access is provided to the US and international community.

  4. High Resolution Simulation in the Eastern Amazonia

    NASA Astrophysics Data System (ADS)

    Cohen, J.; Sa, L.; Nogueira, D.; Gandu, A.

    2006-05-01

    produced by the BRAMS model shows that the numerical simulation reproduced both LLJs of November 13 and 14 at, 06 UTC. However, their magnitude was about 2 and 3 m/s lower and their height was higher than what was observed. In order to verify the origin of the LLJ, the variability of the wind at the jet level, during the numerical simulation in grid 1, was analyzed. In the afternoon, it was observed the increase in wind speed at the Atlantic Coast associated to sea breeze circulation. Nonetheless, at 00 UTC, this maximum speed center penetrated the continent and reached the region of Caxiuanã. Indeed, this circulation was under a canalization effect due to the rivers distribution. On November 13, the sea breeze formed again. However, the circulation on this day was relatively weak. The numerical simulations with this high resolution model indicated the occurrence of low level jets. Nevertheless, it did not reproduce in detail some of the observed characteristics of the flow. An important aspect revealed by the simulations with BRAMS was the origin of the jets, which is associated to a phenomenon of canalization of the flow above zones where there are some of the great rivers in the Northeast of Para.

  5. High-Resolution US of Rheumatologic Diseases.

    PubMed

    Taljanovic, Mihra S; Melville, David M; Gimber, Lana H; Scalcione, Luke R; Miller, Margaret D; Kwoh, C Kent; Klauser, Andrea S

    2015-01-01

    For the past 15 years, high-resolution ultrasonography (US) is being routinely and increasingly used for initial evaluation and treatment follow-up of rheumatologic diseases. This imaging technique is performed by using high-frequency linear transducers and has proved to be a powerful diagnostic tool in evaluation of articular erosions, simple and complex joint and bursal effusions, tendon sheath effusions, and synovitis, with results comparable to those of magnetic resonance imaging, excluding detection of bone marrow edema. Crystal deposition diseases including gouty arthropathy and calcium pyrophosphate deposition disease (CPPD) have characteristic appearances at US, enabling differentiation between these two diseases and from inflammatory arthropathies. Enthesopathy, which frequently accompanies psoriatic and reactive arthritis, also has a characteristic appearance at high-resolution US, distinguishing these two entities from other inflammatory and metabolic arthropathies. The presence of Doppler signal in examined joints, bursae, and tendon sheaths indicates active synovitis. Microbubble echo contrast agents augment detection of tissue vascularity and may act in the future as a drug delivery vehicle. Frequently, joint, tendon sheath, and bursal fluid aspirations and therapeutic injections are performed under US guidance. The authors describe the high-resolution US technique including gray-scale, color or power Doppler, and contrast agent-enhanced US that is used in evaluation of rheumatologic diseases of the wrist and hand and the ankle and foot in their routine clinical practice. This article demonstrates imaging findings of normal joints, rheumatoid arthritis, gouty arthritis, CPPD, psoriatic and reactive arthritis, and osteoarthritis. PMID:26562235

  6. Advances in DNA sequencing technologies for high resolution HLA typing.

    PubMed

    Cereb, Nezih; Kim, Hwa Ran; Ryu, Jaejun; Yang, Soo Young

    2015-12-01

    This communication describes our experience in large-scale G group-level high resolution HLA typing using three different DNA sequencing platforms - ABI 3730 xl, Illumina MiSeq and PacBio RS II. Recent advances in DNA sequencing technologies, so-called next generation sequencing (NGS), have brought breakthroughs in deciphering the genetic information in all living species at a large scale and at an affordable level. The NGS DNA indexing system allows sequencing multiple genes for large number of individuals in a single run. Our laboratory has adopted and used these technologies for HLA molecular testing services. We found that each sequencing technology has its own strengths and weaknesses, and their sequencing performances complement each other. HLA genes are highly complex and genotyping them is quite challenging. Using these three sequencing platforms, we were able to meet all requirements for G group-level high resolution and high volume HLA typing. PMID:26423536

  7. High-resolution flurescence spectroscopy in immunoanalysis

    SciTech Connect

    Grubor, Nenad M.

    2005-05-01

    The work presented in this dissertation combines highly sensitive and selective fluorescence line-narrowing spectroscopy (FLNS) detection with various modes of immunoanalytical techniques. It has been shown that FLNS is capable of directly probing molecules immunocomplexed with antibodies, eliminating analytical ambiguities that may arise from interferences that accompany traditional immunochemical techniques. Moreover, the utilization of highly cross-reactive antibodies for highly specific analyte determination has been demonstrated. Finally, they demonstrate the first example of the spectral resolution of diastereomeric analytes based on their interaction with a cross-reactive antibody.

  8. The Chirp - High Resolution, Quantitative Subbottom Profiler.

    NASA Astrophysics Data System (ADS)

    Schock, Steven Gregory

    The chirp sonar is a quantitative subbottom profiler that can generate wide dynamic range, artifact-free seismograms in real time. These high quality seismograms, can be used for quantitative analyses, such as reflectivity and attenuation measurements, and sediment classification. Key features of the chirp sonar include (1) a computer-generated FM pilot signal with a large time-bandwidth product that contains amplitude and phase compensation providing exact control of the transmitted acoustic pulse (2) directional arrays with low backlobe levels and (3) a towed vehicle designed to scatter bottom multiples. Subbottom profiles, acquired in Narragansett Bay, R.I., demonstrated 20 cm vertical resolution, 62 meter subbottom penetration and significant bottom multiple reduction. A new time domain technique for estimating acoustic attenuation, called the autocorrelation method, is described and compared to well known attenuation measurement techniques. The spectral ratio method is most accurate, followed by the autocorrelation and wavelet matching methods for estimating the acoustic attenuation coefficient of sediments from reflection profiles. However, the autocorrelation method is the only technique efficient enough to provide an attenuation measurement for every depth increment in each acoustic return in real time. Multiple reflections, gradual impedance changes and windowing sidelobes degrade the attenuation estimates. Chirp sonar remote measurements off Hope Island were used to estimate the attenuation coefficient for clayey silts (0.091 dB/m/kHz by spectral ratio and 0.125 dB/m/kHz by autocorrelation), values which agree with in situ measurements made by Hamilton, but are significantly higher than the attenuation coefficient (0.019 dB/m/kHz, n = 1.50) calculated from laboratory measurements (250-750 kHz) on a core from the Hope Island site. More ground truth measurements are required to establish the accuracy of remote attenuation measurements using the chirp sonar.

  9. High-resolution Visible Spectra of Titan

    NASA Astrophysics Data System (ADS)

    Sim, Chae Kyung; Kim, S.

    2006-09-01

    We have obtained high-resolution (R 30,000) spectra of Titan between 4,000 and 10,000 A on Feb. 23, 2005 (UT) using an optical echelle spectrograph (BOES) on the 1.8-m telescope at Bohyunsan Observatory, Korea. The raw Titan spectra contain telluric and solar absorption/emission lines. We used Kitt Peak solar atlases to remove the solar lines effectively. We also constructed synthetic spectra for the atmosphere of Titan including haze layers and utilizing laboratory spectra of CH4 available in literature. Preliminary results on the identifications of weak CH4 lines and on the derived opacities of the haze layers will be presented. Since the observations were carried out near the activities of Cassini observations of Titan, these high-resolution visible spectra are complementary to Cassini/VIMS imagery.

  10. High-Resolution Broadband Spectral Interferometry

    SciTech Connect

    Erskine, D J; Edelstein, J

    2002-08-09

    We demonstrate solar spectra from a novel interferometric method for compact broadband high-resolution spectroscopy. The spectral interferometer (SI) is a hybrid instrument that uses a spectrometer to externally disperse the output of a fixed-delay interferometer. It also has been called an externally dispersed interferometer (EDI). The interferometer can be used with linear spectrometers for imaging spectroscopy or with echelle spectrometers for very broad-band coverage. EDI's heterodyning technique enhances the spectrometer's response to high spectral-density features, increasing the effective resolution by factors of several while retaining its bandwidth. The method is extremely robust to instrumental insults such as focal spot size or displacement. The EDI uses no moving parts, such as purely interferometric FTS spectrometers, and can cover a much wider simultaneous bandpass than other internally dispersed interferometers (e.g. HHS or SHS).

  11. High-resolution scanning hall probe microscopy

    NASA Astrophysics Data System (ADS)

    Hicks, C. W.; Guikema, J. W.; Zeldov, E.

    2005-03-01

    Scanning hall sensors can be used to directly image magnetic fields at surfaces. They offer high resolution, high sensitivity, operability from cryogenic to room temperature, and linearity. We have fabricated hall sensors on GaAs / Al0.35Ga0.65As and GaAs / Al0.3Ga0.7As heterostructures, one containing a 2D electron gas 40 nanometers below the surface and another 140nm below the surface, as well as an In0.5Al0.5As / GaSb / AlSb / InAs heterostructure containing a 2DEG 21nm below the surface. The sensitive areas of our probes range from microns to 60nm on a side. We report on the field sensitivities of the probes and their spatial resolution in a scanning configuration.

  12. Information extraction from high resolution satellite images

    NASA Astrophysics Data System (ADS)

    Yang, Haiping; Luo, Jiancheng; Shen, Zhanfeng; Xia, Liegang

    2014-11-01

    Information extracted from high resolution satellite images, such as roads, buildings, water and vegetation, has a wide range of applications in disaster assessment and environmental monitoring. At present, object oriented supervised learning is usually used in the objects identification from the high spatial resolution satellite images. In classical ways, we have to label some regions of interests from every image to be classified at first, which is labor intensive. In this paper, we build a feature base for information extraction in order to reduce the labeling efforts. The features stored are regulated and labeled. The labeled samples for a new coming image can be selected from the feature base. And the experiments are taken on GF-1 and ZY-3 images. The results show the feasibility of the feature base for image interpretation.

  13. Petrous apex mucocele: high resolution CT.

    PubMed

    Memis, A; Memis, A; Alper, H; Calli, C; Ozer, H; Ozdamar, N

    1994-11-01

    Mucocele of the petrous apex is very rare, only three cases having been reported. Since this area is inaccessible to direct examination, imaging, preferably high resolution computed tomography (HR CT) is essential. We report a case showing an eroding, non enhancing mass with sharp, lobulated contours, within the petrous apex. The presence of a large air cell on the opposite side suggested a mucocele. PMID:7862284

  14. Star formation seen with high resolution spectroscopy.

    NASA Astrophysics Data System (ADS)

    Winnewisser, G.

    1990-03-01

    More than 90 anorganic and organic molecules have been detected by high resolution spectroscopy in interstellar molecular clouds or in the envelopes of stars. The detected wavelengths of the lines - predominantly located in the millimeter- and submillimeter wavelength region - unequivocally identify the molecules and give precise knowledge of the physical and chemical conditions of molecular clouds from which the radiation emanates. The line intensities and line profiles contain information about the densities, temperatures and dynamics prevailing in molecular clouds.

  15. High spatial resolution passive microwave sounding systems

    NASA Technical Reports Server (NTRS)

    Staelin, D. H.; Rosenkranz, P. W.; Bonanni, P. G.; Gasiewski, A. W.

    1986-01-01

    Two extensive series of flights aboard the ER-2 aircraft were conducted with the MIT 118 GHz imaging spectrometer together with a 53.6 GHz nadir channel and a TV camera record of the mission. Other microwave sensors, including a 183 GHz imaging spectrometer were flown simultaneously by other research groups. Work also continued on evaluating the impact of high-resolution passive microwave soundings upon numerical weather prediction models.

  16. Conversational high resolution mass spectrographic data reduction

    NASA Technical Reports Server (NTRS)

    Romiez, M. P.

    1973-01-01

    A FORTRAN 4 program is described which reduces the data obtained from a high resolution mass spectrograph. The program (1) calculates an accurate mass for each line on the photoplate, and (2) assigns elemental compositions to each accurate mass. The program is intended for use in a time-shared computing environment and makes use of the conversational aspects of time-sharing operating systems.

  17. Adaptive Resolution Simulations with Self-Adjusting High-Resolution Regions.

    PubMed

    Kreis, Karsten; Potestio, Raffaello; Kremer, Kurt; Fogarty, Aoife C

    2016-08-01

    In adaptive resolution simulations, different regions of a simulation box are modeled with different levels of detail. Particles change their resolution on-the-fly when traveling from one subregion to the other. This method is particularly useful for studying multiscale systems in which effects on a broad range of length and time scales play a role. Until now, the geometry of the high-resolution region has been limited to simple geometries of spherical, cuboid, or cylindrical form, whose shape does not change during the simulation. However, many phenomena involve changes in size and shape of system components, for example, protein folding, polymer collapse, nucleation, and crystallization. In this work, we develop a scheme that uses a series of overlapping spheres to allow for an arbitrary division of space into domains of different levels of resolution. Furthermore, the geometry is automatically adjusted on-the-fly during the simulation according to changes in size and shape of, for example, a solvated macromolecule within the high-resolution region. The proposed approach is validated on liquid water. We then simulate the folding of an atomistically detailed polypeptide solvated in a shell of atomistic water that changes shape as the peptide conformation changes. We demonstrate that the peptide folding process is unperturbed by the use of our methodology. PMID:27384753

  18. High resolution spectrograph for the Space Telescope

    NASA Technical Reports Server (NTRS)

    Brandt, J. C.; Boggess, A.; Heap, S. R.; Maran, S. P.; Smith, A. M.; Beaver, E. A.; Bottema, M.; Hutchings, J. B.; Jura, M. A.; Linsky, J. L.

    1979-01-01

    The high resolution spectrograph (HRS) for ultraviolet astronomy with the Space Telescope will provide a spectral resolution of approximately 120,000 over a nominal wavelength range of 110-320 nm, together with a spatial resolution of about 0.25 arc seconds. The two detectors will consist of 512-element Digicons with cesium telluride and cesium iodide photocathodes, respectively. Photoelectrons in transit between the photocathodes and the diodes within the Digicons can be deflected in two axes with 12-bit resolution. This feature facilitates a design that emphasizes reliability since (once a hermetic seal is opened in orbit), only two moving parts, a grating carrousel and a shutter, are required for regular operation of the HRS. The instrument will be controlled by a computer in the spacecraft. The scientific objectives of the HRS investigation relate to interstellar matter in our own and nearby galaxies, physical processes of stellar mass loss and mass transfer, chemical abundances, bright quasars and Seyfert galaxy nuclei, and solar system phenomena.

  19. High blood cholesterol levels

    MedlinePlus

    Steps you can take to improve their cholesterol levels, and help prevent heart disease and a heart attack include: Quit smoking. This is the single biggest change you can make to reduce your risk of heart attack and stroke. Eat foods ...

  20. Gamma-aminobutyric acid and glutamic acid levels in the auditory pathway of rats with chronic tinnitus: a direct determination using high resolution point-resolved proton magnetic resonance spectroscopy (1H-MRS)

    PubMed Central

    Brozoski, Thomas; Odintsov, Boris; Bauer, Carol

    2012-01-01

    Damage to the auditory system following high-level sound exposure reduces afferent input. Homeostatic mechanisms appear to compensate for the loss. Overcompensation may produce the sensation of sound without an objective physical correlate, i.e., tinnitus. Several potential compensatory neural processes have been identified, such as increased spontaneous activity. The cellular mechanisms enabling such compensatory processes may involve down-regulation of inhibitory neurotransmission mediated by γ-amino butyric acid (GABA), and/or up-regulation of excitatory neurotransmission, mediated by glutamic acid (Glu). Because central processing systems are integrated and well-regulated, compensatory changes in one system may produce reactive changes in others. Some or all may be relevant to tinnitus. To examine the roles of GABA and Glu in tinnitus, high resolution point-resolved proton magnetic resonance spectroscopy (1H-MRS) was used to quantify their levels in the dorsal cochlear nucleus (DCN), inferior colliculus (IC), medial geniculate body (MGB), and primary auditory cortex (A1) of rats. Chronic tinnitus was produced by a single high-level unilateral exposure to noise, and was measured using a psychophysical procedure sensitive to tinnitus. Decreased GABA levels were evident only in the MGB, with the greatest decrease, relative to unexposed controls, obtained in the contralateral MGB. Small GABA increases may have been present bilaterally in A1 and in the contralateral DCN. Although Glu levels showed considerable variation, Glu was moderately and bilaterally elevated both in the DCN and in A1. In the MGB Glu was increased ipsilaterally but decreased contralaterally. These bidirectional and region-specific alterations in GABA and Glu may reflect large-scale changes in inhibitory and excitatory equilibrium accompanying chronic tinnitus. The present results also suggest that targeting both neurotransmitter systems may be optimal in developing more effective therapeutics

  1. Binary Cepheids From High-Angular Resolution

    NASA Astrophysics Data System (ADS)

    Gallenne, A.; Mérand, A.; Kervella, P.

    2015-12-01

    Optical interferometry is the only technique giving access to milli-arcsecond (mas) spatial resolution. This is a powerful and unique tool to detect the close orbiting companions of Cepheids, and offers an unique opportunity to make progress in resolving the Cepheid mass discrepancy. Our goal in studying binary Cepheids is to measure the astrometric position of the high-contrast companion, and then combine them with spectroscopic measurements to derive the orbital elements, distances, and dynamical masses. In the course of this program, we developed a new tool, CANDID, to search for high-contrast companions and set detection limits from interferometric observations

  2. High-resolution structure of viruses from random diffraction snapshots

    PubMed Central

    Hosseinizadeh, A.; Schwander, P.; Dashti, A.; Fung, R.; D'Souza, R. M.; Ourmazd, A.

    2014-01-01

    The advent of the X-ray free-electron laser (XFEL) has made it possible to record diffraction snapshots of biological entities injected into the X-ray beam before the onset of radiation damage. Algorithmic means must then be used to determine the snapshot orientations and thence the three-dimensional structure of the object. Existing Bayesian approaches are limited in reconstruction resolution typically to 1/10 of the object diameter, with the computational expense increasing as the eighth power of the ratio of diameter to resolution. We present an approach capable of exploiting object symmetries to recover three-dimensional structure to high resolution, and thus reconstruct the structure of the satellite tobacco necrosis virus to atomic level. Our approach offers the highest reconstruction resolution for XFEL snapshots to date and provides a potentially powerful alternative route for analysis of data from crystalline and nano-crystalline objects. PMID:24914154

  3. EFTEM spectrum imaging at high-energy resolution.

    PubMed

    Schaffer, Bernhard; Kothleitner, Gerald; Grogger, Werner

    2006-01-01

    This paper deals with the application of high-energy resolution EFTEM image series and the corrections needed for reliable data interpretation. The detail of spectral information gained from an image series is largely determined by the intrinsic energy resolution. In this work we show that energy resolution values of as low as 0.8 eV in spectra extracted from EFTEM image series can be obtained with a small energy-selecting slit. At this resolution level aberrations of the energy filter, in particular the non-isochromaticity, can no longer be neglected. We show that the four most prominent factors for EFTEM image series data correction--spatial drift, non-isochromaticity, energy drift and image distortion--must not be treated independently but have to be corrected in unison. We present an efficient algorithm for this correction, and demonstrate the applied correction for the case of a GaN/AlN multilayer sample. PMID:16872748

  4. High resolution analysis of the rotational levels of the (0 0 0), (0 1 0), (1 0 0), (0 0 1), (0 2 0), (1 1 0) and (0 1 1) vibrational states of 34S16O2

    SciTech Connect

    Lafferty, Walter; Flaud, Jean-marie; Sams, Robert L.; Ngom, El Hadji A.

    2008-11-01

    A high resolution (0.0018 cm-1) Fourier transform instrument has been used to record the spectrum of an enriched 34S (95.3 %) sample of sulfur dioxide. A thorough analysis of the ν2, 2ν2 - ν2 , ν1, ν1 + ν2 - ν2, ν3, ν2 + ν3 - ν2, ν1 + ν2 and ν2 + ν3 bands has been carried out leading to a large set of assigned lines. From these lines ground state combination differences were obtained and fitted together with the existing microwave, millimeter, and terahertz rotational lines. An improved set of ground state rotational constants were obtained. Next, the upper state rotational levels were fitted. For the (010), (110), (011) states, a simple Watson type Hamilton sufficed. However, it was necessary to include explicitly interacting terms in the Hamiltonian matrix in order to fit the rotational levels of the (020), (100) and (101) states to within their experimental accuracy. More explicitly, it was necessary to use a ΔK=2 term to model the Fermi interaction between the (020) and (100) levels and a ΔK=3 term to model the Coriolis interaction between the (100) and (001) levels. Precise Hamiltonian constants were derived for the (000), (010), (100), (001), (020), (110) and (011) vibrational states.

  5. Computer synthesis of high resolution electron micrographs

    NASA Technical Reports Server (NTRS)

    Nathan, R.

    1976-01-01

    Specimen damage, spherical aberration, low contrast and noisy sensors combine to prevent direct atomic viewing in a conventional electron microscope. The paper describes two methods for obtaining ultra-high resolution in biological specimens under the electron microscope. The first method assumes the physical limits of the electron objective lens and uses a series of dark field images of biological crystals to obtain direct information on the phases of the Fourier diffraction maxima; this information is used in an appropriate computer to synthesize a large aperture lens for a 1-A resolution. The second method assumes there is sufficient amplitude scatter from images recorded in focus which can be utilized with a sensitive densitometer and computer contrast stretching to yield fine structure image details. Cancer virus characterization is discussed as an illustrative example. Numerous photographs supplement the text.

  6. High-resolution adaptive spiking sonar.

    PubMed

    Alvarez, Fernando J; Kuc, Roman

    2009-05-01

    A new sonar system based on the conventional 6500 ranging module is presented that generates a sequence of spikes whose temporal density is related to the strength of the received echo. This system notably improves the resolution of a previous system by shortening the discharge cycle of the integrator included in the module. The operation is controlled by a PIC18F452 device, which can adapt the duration of the discharge to changing features of the echo, providing the system with a novel adaptive behavior. The performance of the new sensor is characterized and compared with that of the previous system by performing rotational scans of simple objects with different reflecting strengths. Some applications are suggested that exploit the high resolution and adaptability of this sensor. PMID:19473919

  7. Orbiter glow observations at high spectral resolution

    NASA Technical Reports Server (NTRS)

    Kendall, D. J. W.; Mende, S. B.; Yn, E. J. ADMCDADE, I. C. AEMENDE, S. B.

    1985-01-01

    An experiment flow on mission STS 41-G as part of the Canadian complement of experiments was designed to obtain relatively high resolution spectra of the Orbiter glow phenomenon over limited spectral regions centered on prominent upper atmospheric emissions. Observations were carried out successfully at altitudes of 360 km and 230 km although those at the lower altitude were limited by degradation of the image intensifier. Definitive glow results were obtained at the end of a thruster firing which showed the spectrum to be a continuum at a resolution of approximately 0.4 nm centered at a wavelength of 360 nm. Results at other wavelengths in the absence of any firings strongly suggest that the Orbiter glow is a continuum throughout the spectral region 550 nm to 760 nm. A discussion is presented that considers the reaction NO + O2 as being a possible candidate for the mechanism producing the shuttle glow.

  8. High resolution patterning of silica aerogels

    SciTech Connect

    Bertino, M.F.; Hund, J.F.; Sosa, J.; Zhang, G.; Sotiriou-Leventis, C.; Leventis, N.; Tokuhiro, A.T.; Terry, J.

    2008-10-30

    Three-dimensional metallic structures are fabricated with high spatial resolution in silica aerogels. In our method, silica hydrogels are prepared with a standard base-catalyzed route, and exchanged with an aqueous solution typically containing Ag{sup +} ions (1 M) and 2-propanol (0.2 M). The metal ions are reduced photolytically with a table-top ultraviolet lamp, or radiolytically, with a focused X-ray beam. We fabricated dots and lines as small as 30 x 70 {micro}m, protruding for several mm into the bulk of the materials. The hydrogels are eventually supercritically dried to yield aerogels, without any measurable change in the shape and spatial resolution of the lithographed structures. Transmission electron microscopy shows that illuminated regions are composed by Ag clusters with a size of several {micro}m, separated by thin layers of silica.

  9. Stellar population models at high spectral resolution

    NASA Astrophysics Data System (ADS)

    Maraston, C.; Strömbäck, G.

    2011-12-01

    We present new, high-to-intermediate spectral resolution stellar population models, based on four popular libraries of empirical stellar spectra, namely Pickles, ELODIE, STELIB and MILES. These new models are the same as our previous models, but with higher resolution and based on empirical stellar spectra, while keeping other ingredients the same including the stellar energetics, the atmospheric parameters and the treatment of the thermally pulsating asymptotic giant branch and the horizontal branch morphology. We further compute very high resolution (R= 20 000) models based on the theoretical stellar library MARCS which extends to the near-infrared. We therefore provide merged high-resolution stellar population models, extending from ˜1000 to 25 000 Å, using our previously published high-resolution theoretical models which extended to the ultraviolet. We compare how these libraries perform in stellar population models and highlight spectral regions where discrepancies are found. We confirm our previous findings that the flux around the V band is lower (in a normalized sense) in models based on empirical libraries than in those based on the BaSeL-Kurucz library, which results in a bluer B-V colour. Most noticeably the theoretical library MARCS gives results fully consistent with the empirical libraries. This same effect is also found in other models using MILES, namely Vazdekis et al. and Conroy & Gunn, even though the latter authors reach the opposite conclusion. The bluer predicted B-V colour (by 0.05 mag in our models) is in better agreement with both the colours of luminous red galaxies and globular cluster data. We test the models on their ability to reproduce, through full spectral fitting, the ages and metallicities of Galactic globular clusters as derived from colour-magnitude diagram (CMD) fitting and find overall good agreement. We also discuss extensively the Lick indices calculated directly on the integrated MILES-based spectral energy distributions

  10. The theory and practice of high resolution scanning electron microscopy

    SciTech Connect

    Joy, D.C. Oak Ridge National Lab., TN )

    1990-01-01

    Recent advances in instrumentation have produced the first commercial examples of what can justifiably be called High Resolution Scanning Electron Microscopes. The key components of such instruments are a cold field emission gun, a small-gap immersion probe-forming lens, and a clean dry-pumped vacuum. The performance of these microscopes is characterized by several major features including a spatial resolution, in secondary electron mode on solid specimens, which can exceed 1nm on a routine basis; an incident probe current density of the order of 10{sup 6} amps/cm{sup 2}; and the ability to maintain these levels of performance over an accelerating voltage range of from 1 to 30keV. This combination of high resolution, high probe current, low contamination and flexible electron-optical conditions provides many new opportunitites for the application of the SEM to materials science, physics, and the life sciences. 27 refs., 14 figs.

  11. High-resolution simulation of field emission

    SciTech Connect

    Herrmannsfeldt, W.B. ); Becker, R. ); Brodie, I.; Rosengreen, A.; Spindt, C.A. )

    1990-03-01

    High-resolution simulations of field emission electron sources have been made using the electron optics program EGN2. Electron emission distributions are made using the Fowler-Nordheim equation. Mesh resolution in the range of 1-5 {angstrom} is required to adequately model surface details that can result in emission currents in the range found experimentally. A typical problem starts with mechanical details with dimensions of about 1{mu}. To achieve high resolution a new boundary is defined by the tip, a nearby equipotential line, and a pair of field lines. The field lines (one of which is normally the axis of symmetry) define Neumann boundaries. This new boundary is then used by the boundary preprocessor POLYGON to create an enlarged version of the problem, typically by a factor of ten. This process can be repeated until adequate resolution is obtained to simulate surface details, such as microprotusion, that could sufficiently enhance the surface electric fields and cause field emission. When simulating experimental conditions under which emission of several microamperes per tip were observed, it was found that both a locally reduced work function and a surface protrusion were needed to duplicate the experimental results. If only a local region of reduced work function is used, the area involved and the extent of the reduction both need to be very large to reproduce the emission. If only a surface protrusion is used, it is possible to get the observed emission current with a reasonable protrusion of length a few times radius, but then the resulting beam spreads over a very large solid angle due to the strong local radial electric fields. 8 refs., 14 figs., 1 tab.

  12. Evacuee Compliance Behavior Analysis using High Resolution Demographic Information

    SciTech Connect

    Lu, Wei; Han, Lee; Liu, Cheng; Tuttle, Mark A; Bhaduri, Budhendra L

    2014-01-01

    The purpose of this study is to examine whether evacuee compliance behavior with route assignments from different resolutions of demographic data would impact the evacuation performance. Most existing evacuation strategies assume that travelers will follow evacuation instructions, while in reality a certain percent of evacuees do not comply with prescribed instructions. In this paper, a comparison study of evacuation assignment based on Traffic Analysis Zones (TAZ) and high resolution LandScan USA Population Cells (LPC) were conducted for the detailed road network representing Alexandria, Virginia. A revised platform for evacuation modeling built on high resolution demographic data and activity-based microscopic traffic simulation is proposed. The results indicate that evacuee compliance behavior affects evacuation efficiency with traditional TAZ assignment, but it does not significantly compromise the efficiency with high resolution LPC assignment. The TAZ assignment also underestimates the real travel time during evacuation, especially for high compliance simulations. This suggests that conventional evacuation studies based on TAZ assignment might not be effective at providing efficient guidance to evacuees. From the high resolution data perspective, traveler compliance behavior is an important factor but it does not impact the system performance significantly. The highlight of evacuee compliance behavior analysis should be emphasized on individual evacuee level route/shelter assignments, rather than the whole system performance.

  13. Identifying new opportunities for exoplanet characterisation at high spectral resolution

    NASA Astrophysics Data System (ADS)

    de Kok, R. J.; Birkby, J.; Brogi, M.; Schwarz, H.; Albrecht, S.; de Mooij, E. J. W.; Snellen, I. A. G.

    2014-01-01

    Context. Recently, there have been a series of detections of molecules in the atmospheres of extrasolar planets using high spectral resolution (R ~ 100 000) observations, mostly using the CRyogenic high-resolution InfraRed Echelle Spectrograph (CRIRES) on the Very Large Telescope. These measurements are able to resolve molecular bands into individual absorption lines. Observing many lines simultaneously as their Doppler shift changes with time allows the detection of specific molecules in the atmosphere of the exoplanet. Aims: We aim to identify new ways of increasing the planet signal in these kinds of high-resolution observations. First of all, we wish to determine what wavelength settings can best be used to target certain molecules. Furthermore, we want to simulate exoplanet spectra of the day-side and night-side to see whether night-side observations are feasible at high spectral resolution. Methods: We performed simulations of high-resolution CRIRES observations of a planet's thermal emission and transit between 1 and 5 μm and performed a cross-correlation analysis on these results to assess how well the planet signal can be extracted. These simulations take into account telluric absorption, sky emission, realistic noise levels, and planet-to-star contrasts. We also simulated day-side and night-side spectra at high spectral resolution for planets with and without a day-side temperature inversion, based on the cases of HD 189733b and HD 209458b. Results: Several small wavelength regions in the L-band promise to yield cross-correlation signals from the thermal emission of hot Jupiters of H2O, CH4, CO2, C2H2, and HCN that can exceed those of the current detections by up to a factor of 2-3 for the same integration time. For transit observations, the H-band is also attractive, with the H, K, and L-bands giving cross-correlation signals of similar strength. High-resolution night-side spectra of hot Jupiters can give cross-correlation signals as high as the day

  14. High resolution hyperspectral imaging with a high throughput virtual slit

    NASA Astrophysics Data System (ADS)

    Gooding, Edward A.; Gunn, Thomas; Cenko, Andrew T.; Hajian, Arsen R.

    2016-05-01

    Hyperspectral imaging (HSI) device users often require both high spectral resolution, on the order of 1 nm, and high light-gathering power. A wide entrance slit assures reasonable étendue but degrades spectral resolution. Spectrometers built using High Throughput Virtual Slit™ (HTVS) technology optimize both parameters simultaneously. Two remote sensing use cases that require high spectral resolution are discussed. First, detection of atmospheric gases with intrinsically narrow absorption lines, such as hydrocarbon vapors or combustion exhaust gases such as NOx and CO2. Detecting exhaust gas species with high precision has become increasingly important in the light of recent events in the automobile industry. Second, distinguishing reflected daylight from emission spectra in the visible and NIR (VNIR) regions is most easily accomplished using the Fraunhofer absorption lines in solar spectra. While ground reflectance spectral features in the VNIR are generally quite broad, the Fraunhofer lines are narrow and provide a signature of intrinsic vs. extrinsic illumination. The High Throughput Virtual Slit enables higher spectral resolution than is achievable with conventional spectrometers by manipulating the beam profile in pupil space. By reshaping the instrument pupil with reflective optics, HTVS-equipped instruments create a tall, narrow image profile at the exit focal plane, typically delivering 5X or better the spectral resolution achievable with a conventional design.

  15. High Spectral Resolution Lidar: System Calibration

    NASA Astrophysics Data System (ADS)

    Vivek Vivekanandan, J.; Morley, Bruce; Spuler, Scott; Eloranta, Edwin

    2015-04-01

    One of the unique features of the high spectral resolution lidar (HSRL) is simultaneous measurements of backscatter and extinction of atmosphere. It separates molecular scattering from aerosol and cloud particle backscatter based on their Doppler spectrum width. Scattering from aerosol and cloud particle are referred as Mie scattering. Molecular or Rayleigh scattering is used as a reference for estimating aerosol extinction and backscatter cross-section. Absolute accuracy of the backscattered signals and their separation into Rayleigh and Mie scattering depends on spectral purity of the transmitted signals, accurate measurement of transmit power, and precise performance of filters. Internal calibration is used to characterize optical subsystems Descriptions of high spectral resolution lidar system and its measurement technique can be found in Eloronta (2005) and Hair et al.(2001). Four photon counting detectors are used to measure the backscatter from the combined Rayleigh and molecular scattering (high and low gain), molecular scattering and cross-polarized signal. All of the detectors are sensitive to crosstalk or leakage through the optical filters used to separate the received signals and special data files are used to remove these effects as much as possible. Received signals are normalized with respect to the combined channel response to Mie and Rayleigh scattering. The laser transmit frequency is continually monitored and tuned to the 1109 Iodine absorption line. Aerosol backscatter cross-section is measured by referencing the aerosol return signal to the molecular return signal. Extinction measurements are calculated based on the differences between the expected (theoretical) and actual change in the molecular return. In this paper an overview of calibration of the HSRL is presented. References: Eloranta, E. W., High Spectral Resolution Lidar in Lidar: Range-Resolved Optical Remote Sensing of the Atmosphere, Klaus Weitkamp editor, Springer Series in Optical

  16. A medium resolution minefield model suitable for entity-level resolution combat simulations

    SciTech Connect

    Powell, E.T.

    1994-06-09

    A new, flexible, and realistic representation of conventional minefields in entity-level resolution combat simulations is presented. The model includes important aspects of minefield effects on battlefield entities and of breaching devices on minefields. The model is designed at ``medium resolution,`` that is, it is general enough to depict a wide variety of tactical situations accurately; however, it only represents tactically significant aspects of mine warfare, discarding or aggregating details, thus minimizing computer memory and speed requirements. This paper describes the model in detail, its implementation in the Janus simulation code, and its use in a preliminary analysis effort related to the effect of delay on the tactical battlefield.

  17. Development of a high resolution and high dispersion Thomson parabola

    NASA Astrophysics Data System (ADS)

    Jung, D.; Hörlein, R.; Kiefer, D.; Letzring, S.; Gautier, D. C.; Schramm, U.; Hübsch, C.; Öhm, R.; Albright, B. J.; Fernandez, J. C.; Habs, D.; Hegelich, B. M.

    2011-01-01

    Here, we report on the development of a novel high resolution and high dispersion Thomson parabola for simultaneously resolving protons and low-Z ions of more than 100 MeV/nucleon necessary to explore novel laser ion acceleration schemes. High electric and magnetic fields enable energy resolutions of ΔE/E < 5% at 100 MeV/nucleon and impede premature merging of different ion species at low energies on the detector plane. First results from laser driven ion acceleration experiments performed at the Trident Laser Facility demonstrate high resolution and superior species and charge state separation of this novel Thomson parabola for ion energies of more than 30 MeV/nucleon.

  18. Development of a high resolution and high dispersion Thomson parabola.

    PubMed

    Jung, D; Hörlein, R; Kiefer, D; Letzring, S; Gautier, D C; Schramm, U; Hübsch, C; Öhm, R; Albright, B J; Fernandez, J C; Habs, D; Hegelich, B M

    2011-01-01

    Here, we report on the development of a novel high resolution and high dispersion Thomson parabola for simultaneously resolving protons and low-Z ions of more than 100 MeV/nucleon necessary to explore novel laser ion acceleration schemes. High electric and magnetic fields enable energy resolutions of ΔE∕E < 5% at 100 MeV/nucleon and impede premature merging of different ion species at low energies on the detector plane. First results from laser driven ion acceleration experiments performed at the Trident Laser Facility demonstrate high resolution and superior species and charge state separation of this novel Thomson parabola for ion energies of more than 30 MeV/nucleon. PMID:21280824

  19. High resolution extremity CT for biomechanics modeling

    SciTech Connect

    Ashby, A.E.; Brand, H.; Hollerbach, K.; Logan, C.M.; Martz, H.E.

    1995-09-23

    With the advent of ever more powerful computing and finite element analysis (FEA) capabilities, the bone and joint geometry detail available from either commercial surface definitions or from medical CT scans is inadequate. For dynamic FEA modeling of joints, precise articular contours are necessary to get appropriate contact definition. In this project, a fresh cadaver extremity was suspended in parafin in a lucite cylinder and then scanned with an industrial CT system to generate a high resolution data set for use in biomechanics modeling.

  20. High-Resolution Manometry in Clinical Practice

    PubMed Central

    Pandolfino, John E.

    2015-01-01

    High-resolution manometry (HRM) is the primary method used to evaluate esophageal motor function. Displayed and interpreted by esophageal pressure topography (EPT), HRM/ EPT provides a detailed assessment of esophageal function that is useful in the evaluation of patients with nonobstructive dysphagia and before foregut surgery. Esophageal motility diagnoses are determined systematically by applying objective metrics of esophageal sphincter and peristaltic function to the Chicago Classification of esophageal motility disorders. This article discusses HRM study, EPT interpretation, and the translation of EPT findings into clinical practice. Examples are provided to illustrate several clinical challenges. PMID:27118931

  1. High resolution interferometry of cool stars

    NASA Technical Reports Server (NTRS)

    Lambert, D. L.

    1974-01-01

    A description is given of results obtained in a program of infrared high resolution spectroscopy of cool stars. The nature of infrared stellar spectra is considered along with questions regarding astrophysics and stellar infrared spectroscopy. An abundance analysis for alpha Ori (Betelgeuse) is conducted. The C-12/C-13 abundance ratio is examined and attention is given to the O-16/O-18 and O-16/O-17 abundance ratios. M stars and SiO vibration-rotation bands are discussed and questions regarding the characteristics of the molecular hydrogen quadrupole vibration-rotation lines are explored.

  2. High-resolution color photographic reproductions

    NASA Astrophysics Data System (ADS)

    McCann, John J.

    1997-04-01

    This paper will describe a fine-art reproduction process that: captures painting information with high-resolution color photographs; scans the information into a 300 megabyte digital file; performs a 3D color calibration in a dedicated hardware color-transform circuit; makes a master positive color transparency and makes a reproduction on polaroid color print film. The master transparency can be used to expose a large number of images. This combines the efficiency of instant photography with the color fidelity of digital color transforms.

  3. High Resolution Acoustoelastic Measurements of Materials

    NASA Astrophysics Data System (ADS)

    McKenna, Mark; Guy, Samuel; Heyman, Joseph

    2006-11-01

    As materials become more complex, there is an increasing need for high resolution measurements to characterize strength and damage in the materials. Typically, the criterion for rejecting a part is based on the detection of a flaw of a specific size in a critical location. Interestingly, if a low stress field exists at the flaw site, the flaw may not grow over time. Similarly, in a part that shows no unacceptable indications, a high stress state may cause the flaw to quickly grow through the part leading to failure. In other cases, a controlled amount of stress (in a specific direction or type) is purposely added to the material to prevent flaw growth. Inspection time intervals are based knowing and controlling the stress environment to predict the flaw growth. Luna Innovations Incorporated has developed a high resolution ultrasonic instrument that can enhance the integrity of critical hardware by measuring changes in the stress state in a material. Knowledge of the stress state plus knowledge of crack sizes greatly improves structural engineers' capability of life prediction. System data will be shown for tests to stresses near holes in laboratory fabricated aircraft metal samples. Scans of the spatial distribution of stresses will be compared with finite element models of the structure.

  4. High-Resolution Shadowing of Transfer RNA

    PubMed Central

    Abermann, Reinhard J.; Yoshikami, Doju

    1972-01-01

    High-resolution shadowing with metals that melt at high temperatures was used to study macromolecules. Molecules of transfer RNA shadowed with tantalum-tungsten are readily visualized in an electron microscope. Mounting procedures for tRNA were perfected that reproducibly gave uniform distributions of both monomeric and dimeric tRNA particles, and allowed a statistical assessment of their gross shapes and sizes. Monomeric tRNA yielded a fairly homogeneous population of rod-shaped particles, with axial dimensions of about 40 × 85 Å. Dimers of yeast alanine tRNA held together by hydrogen bonds and dimers constructed by covalent linkage of the amino-acid acceptor (3′-) termini of monomers both gave slightly more heterogeneous populations of particles. Yet, their structures were also basically rod shaped, with their lengths ranging to about twice that of the monomer; this result indicates an end-to-end arrangement of the monomeric units within both dimers. These results suggest that the amino-acid acceptor terminus and the anticodon region are at the ends of the rod-shaped, dehydrated tRNA monomer visible by electron microscopy, consistent with the generally accepted view of tRNA structure in solution suggested by other workers using other methods. This study demonstrates that high-resolution shadowing with tantalum-tungsten provides a means to examine the three-dimensional structures of relatively small biological macromolecules. Images PMID:4504373

  5. Crusta: Visualizing High-resolution Global Data

    NASA Astrophysics Data System (ADS)

    Bernardin, T. S.; Kreylos, O.; Bowles, C. J.; Cowgill, E.; Hamann, B.; Kellogg, L. H.

    2009-12-01

    Virtual globes have become indispensable tools for visualizing, understanding and presenting data from Earth and other planetary bodies. The scientific community has invested much effort into exploiting existing globes to their fullest potential by refining and adapting their capabilities to better satisfy specific needs. For example, Google Earth provides users with the ability to view hillshade images derived from airborne LiDAR data such as the 2007 Northern California GeoEarthScope data. However, because most available globes were not designed with the specific needs of geoscientists in mind, shortcomings are becoming increasingly evident in geoscience applications such as terrain visualization. In particular, earth scientists struggle to visualize digital elevation models with both high spatial resolution (0.5 - 1 square meters per sample) and large extent (>2000 square kilometers), such as those obtained with airborne LiDAR. To address the specific earth science need of real-time terrain visualization of LiDAR data, we are developing Crusta as part of a close collaboration involving earth and computer scientists. Crusta is a new virtual globe that differs from widely used globes by both providing accurate global data representation and the ability to easily visualize custom topographic and image data. As a result, Crusta enables real-time, interactive visualization of high resolution digital elevation data spanning thousands of square kilometers, such as the complete 2007 Northern California GeoEarthScope airborne LiDAR data set. To implement an accurate data representation and avoid distortion of the display at the poles, where other projections have singularities, Crusta represents the globe as a thirty-sided polyhedron. Each side of this polyhedron can be subdivided to an arbitrarily fine grid on the surface of the globe, which allows Crusta to accommodate input data of arbitrary resolution ranging from global (e.g., Blue Marble) to local (e.g., a tripod

  6. Efficient Compression of High Resolution Climate Data

    NASA Astrophysics Data System (ADS)

    Yin, J.; Schuchardt, K. L.

    2011-12-01

    resolution climate data can be massive. Those data can consume a huge amount of disk space for storage, incur significant overhead for outputting data during simulation, introduce high latency for visualization and analysis, and may even make interactive visualization and analysis impossible given the limit of the data that a conventional cluster can handle. These problems can be alleviated by with effective and efficient data compression techniques. Even though HDF5 format supports compression, previous work has mainly focused on employ traditional general purpose compression schemes such as dictionary coder and block sorting based compression scheme. Those compression schemes mainly focus on encoding repeated byte sequences efficiently and are not well suitable for compressing climate data consist mainly of distinguished float point numbers. We plan to select and customize our compression schemes according to the characteristics of high-resolution climate data. One observation on high resolution climate data is that as the resolution become higher, values of various climate variables such as temperature and pressure, become closer in nearby cells. This provides excellent opportunities for predication-based compression schemes. We have performed a preliminary estimation of compression ratios of a very simple minded predication-based compression ratio in which we compute the difference between current float point number with previous float point number and then encoding the exponent and significance part of the float point number with entropy-based compression scheme. Our results show that we can achieve higher compression ratios between 2 and 3 in lossless compression, which is significantly higher than traditional compression algorithms. We have also developed lossy compression with our techniques. We can achive orders of magnitude data reduction while ensure error bounds. Moreover, our compression scheme is much more efficient and introduces much less overhead

  7. High-Resolution Spectroscopy of Some Very Inactive Southern Stars

    NASA Astrophysics Data System (ADS)

    Villarreal, A.; King, J. R.; Soderblom, D. R.; Henry, T. J.

    2001-12-01

    We have obtained high-resolution echelle spectra of a few dozen solar-type stars that an earlier low resolution Ca II H & K survey suggested have modest evels of chromospheric activity. We present Hα -based chromospheric activity measures, binarity information, and Li abundances of the sample. As expected, our spectra: confirm the low levels of chromospheric activity; suggest that these objects are apparently single; indicate the stars have small projected rotational velocities; and yield low photospheric abundances of Li. This work was supported by NSF grant AST-0086576 to JRK.

  8. Performance measurements of a high-spatial-resolution YAP camera.

    PubMed

    Uzunov, N; Bello, M; Boccaccio, P; Moschini, G; Baldazzi, G; Bollini, D; de Notaristefani, F; Mazzi, U; Riondato, M

    2005-02-01

    Physical properties of a position-sensitive camera for the analysis of biodistributions of gamma- and beta-emitting radiopharmaceuticals in small animals have been studied, in order to achieve optimal operating conditions. The camera consisted of a highly segmented yttrium-aluminate perovskite (YAP) scintillator, coupled to a position-sensitive photomultiplier. The energy resolution, the detection efficiency, the spatial resolution, the spatial linearity and the count-rate linearity of the YAP camera have been determined. Images related to initial activity levels and successive biodistribution evolution in mice organs are presented as an illustration of the camera performance. PMID:15773730

  9. Solutions on high-resolution multiple configuration system sensors

    NASA Astrophysics Data System (ADS)

    Liu, Hua; Ding, Quanxin; Guo, Chunjie; Zhou, Liwei

    2014-11-01

    For aim to achieve an improved resolution in modern image domain, a method of continuous zoom multiple configuration, with a core optics is attempt to establish model by novel principle on energy transfer and high accuracy localization, by which the system resolution can be improved with a level in nano meters. A comparative study on traditional vs modern methods can demonstrate that the dialectical relationship and their balance is important, among Merit function, Optimization algorithms and Model parameterization. The effect of system evaluated criterion that MTF, REA, RMS etc. can support our arguments qualitatively.

  10. High Resolution Global View of Io

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Io, the most volcanic body in the solar system is seen in the highest resolution obtained to date by NASA's Galileo spacecraft. The smallest features that can be discerned are 2.5 kilometers in size. There are rugged mountains several kilometers high, layered materials forming plateaus, and many irregular depressions called volcanic calderas. Several of the dark, flow-like features correspond to hot spots, and may be active lava flows. There are no landforms resembling impact craters, as the volcanism covers the surface with new deposits much more rapidly than the flux of comets and asteroids can create large impact craters. The picture is centered on the side of Io that always faces away from Jupiter; north is to the top.

    Color images acquired on September 7, 1996 have been merged with higher resolution images acquired on November 6, 1996 by the Solid State Imaging (CCD) system aboard NASA's Galileo spacecraft. The color is composed of data taken, at a range of 487,000 kilometers, in the near-infrared, green, and violet filters and has been enhanced to emphasize the extraordinary variations in color and brightness that characterize Io's face. The high resolution images were obtained at ranges which varied from 245,719 kilometers to 403,100 kilometers.

    Launched in October 1989, Galileo entered orbit around Jupiter on December 7, 1995. The spacecraft's mission is to conduct detailed studies of the giant planet, its largest moons and the Jovian magnetic environment. The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    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. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  11. High Resolution Powder Diffraction and Structure Determination

    SciTech Connect

    Cox, D. E.

    1999-04-23

    It is clear that high-resolution synchrotrons X-ray powder diffraction is a very powerful and convenient tool for material characterization and structure determination. Most investigations to date have been carried out under ambient conditions and have focused on structure solution and refinement. The application of high-resolution techniques to increasingly complex structures will certainly represent an important part of future studies, and it has been seen how ab initio solution of structures with perhaps 100 atoms in the asymmetric unit is within the realms of possibility. However, the ease with which temperature-dependence measurements can be made combined with improvements in the technology of position-sensitive detectors will undoubtedly stimulate precise in situ structural studies of phase transitions and related phenomena. One challenge in this area will be to develop high-resolution techniques for ultra-high pressure investigations in diamond anvil cells. This will require highly focused beams and very precise collimation in front of the cell down to dimensions of 50 {micro}m or less. Anomalous scattering offers many interesting possibilities as well. As a means of enhancing scattering contrast it has applications not only to the determination of cation distribution in mixed systems such as the superconducting oxides discussed in Section 9.5.3, but also to the location of specific cations in partially occupied sites, such as the extra-framework positions in zeolites, for example. Another possible application is to provide phasing information for ab initio structure solution. Finally, the precise determination of f as a function of energy through an absorption edge can provide useful information about cation oxidation states, particularly in conjunction with XANES data. In contrast to many experiments at a synchrotron facility, powder diffraction is a relatively simple and user-friendly technique, and most of the procedures and software for data analysis

  12. High resolution multimodal clinical ophthalmic imaging system

    PubMed Central

    Mujat, Mircea; Ferguson, R. Daniel; Patel, Ankit H.; Iftimia, Nicusor; Lue, Niyom; Hammer, Daniel X.

    2010-01-01

    We developed a multimodal adaptive optics (AO) retinal imager which is the first to combine high performance AO-corrected scanning laser ophthalmoscopy (SLO) and swept source Fourier domain optical coherence tomography (SSOCT) imaging modes in a single compact clinical prototype platform. Such systems are becoming ever more essential to vision research and are expected to prove their clinical value for diagnosis of retinal diseases, including glaucoma, diabetic retinopathy (DR), age-related macular degeneration (AMD), and retinitis pigmentosa. The SSOCT channel operates at a wavelength of 1 µm for increased penetration and visualization of the choriocapillaris and choroid, sites of major disease activity for DR and wet AMD. This AO system is designed for use in clinical populations; a dual deformable mirror (DM) configuration allows simultaneous low- and high-order aberration correction over a large range of refractions and ocular media quality. The system also includes a wide field (33 deg.) line scanning ophthalmoscope (LSO) for initial screening, target identification, and global orientation, an integrated retinal tracker (RT) to stabilize the SLO, OCT, and LSO imaging fields in the presence of lateral eye motion, and a high-resolution LCD-based fixation target for presentation of visual cues. The system was tested in human subjects without retinal disease for performance optimization and validation. We were able to resolve and quantify cone photoreceptors across the macula to within ~0.5 deg (~100-150 µm) of the fovea, image and delineate ten retinal layers, and penetrate to resolve features deep into the choroid. The prototype presented here is the first of a new class of powerful flexible imaging platforms that will provide clinicians and researchers with high-resolution, high performance adaptive optics imaging to help guide therapies, develop new drugs, and improve patient outcomes. PMID:20589021

  13. High Resolution BPM for Linear Colliders

    NASA Astrophysics Data System (ADS)

    Simon, C.; Chel, S.; Luong, M.; Napoly, O.; Novo, J.; Roudier, D.; Baboi, N.; Noelle, D.; Mildner, N.; Zapfe, K.; Rouvière, N.

    2006-11-01

    A high resolution Beam Position Monitor (BPM) is necessary for the beam-based alignment systems of high energy and low emittance electron linacs. Such a monitor is developed in the framework of the European CARE/SRF programme, in a close collaboration between DESY and CEA/DSM/DAPNIA. This monitor is a radiofrequency re-entrant cavity, which can be used either at room or cryogenic temperature, in an environment where dust particle contamination has to be avoided, such as superconducting cavities in a cryomodule. A first prototype of a re-entrant BPM has already delivered measurements at 2K. inside the first cryomodule (ACC1) on the TESLA Test Facility 2 (TTF2). The performances of this BPM are analyzed both experimentally and theoretically, and the limitations of this existing system clearly identified. A new cavity and new electronics have been designed in order to improve the position resolution down to 1 μm and the damping time down to 10 ns.

  14. Common high-resolution MMW scene generator

    NASA Astrophysics Data System (ADS)

    Saylor, Annie V.; McPherson, Dwight A.; Satterfield, H. DeWayne; Sholes, William J.; Mobley, Scott B.

    2001-08-01

    The development of a modularized millimeter wave (MMW) target and background high resolution scene generator is reported. The scene generator's underlying algorithms are applicable to both digital and real-time hardware-in-the-loop (HWIL) simulations. The scene generator will be configurable for a variety of MMW and multi-mode sensors employing state of the art signal processing techniques. At present, digital simulations for MMW and multi-mode sensor development and testing are custom-designed by the seeker vendor and are verified, validated, and operated by both the vendor and government in simulation-based acquisition. A typical competition may involve several vendors, each requiring high resolution target and background models for proper exercise of seeker algorithms. There is a need and desire by both the government and sensor vendors to eliminate costly re-design and re-development of digital simulations. Additional efficiencies are realized by assuring commonality between digital and HWIL simulation MMW scene generators, eliminating duplication of verification and validation efforts.

  15. Limiting liability via high resolution image processing

    SciTech Connect

    Greenwade, L.E.; Overlin, T.K.

    1996-12-31

    The utilization of high resolution image processing allows forensic analysts and visualization scientists to assist detectives by enhancing field photographs, and by providing the tools and training to increase the quality and usability of field photos. Through the use of digitized photographs and computerized enhancement software, field evidence can be obtained and processed as `evidence ready`, even in poor lighting and shadowed conditions or darkened rooms. These images, which are most often unusable when taken with standard camera equipment, can be shot in the worst of photographic condition and be processed as usable evidence. Visualization scientists have taken the use of digital photographic image processing and moved the process of crime scene photos into the technology age. The use of high resolution technology will assist law enforcement in making better use of crime scene photography and positive identification of prints. Valuable court room and investigation time can be saved and better served by this accurate, performance based process. Inconclusive evidence does not lead to convictions. Enhancement of the photographic capability helps solve one major problem with crime scene photos, that if taken with standard equipment and without the benefit of enhancement software would be inconclusive, thus allowing guilty parties to be set free due to lack of evidence.

  16. High Resolution Spectroscopy of Rocket Triggered Lightning

    NASA Astrophysics Data System (ADS)

    Walker, T. D.; Christian, H. J.

    2012-12-01

    In the Summer of 2012, optical spectra of rocket triggered lightning return strokes were recorded at the International Center for Lightning Research and Testing in north-central Florida. The spectra were recorded with a Phantom v710 high speed CMOS camera running at 670 kfps (kiloframes per second) with a 1 microsecond exposure time and a Princeton ProEM high speed CCD camera running at over 1,000 kfps with a 0.5 microsecond exposure time. Three separate volume phase holographic grisms were used during the study and were sensitive in the spectral ranges of 3800-6200 Angstroms, 6400-6700 Angstroms, 7600-7900 Angstroms. The first had a spectral resolution of 5 Angstroms, allowing the separation of singly ionized nitrogen multiplets. These spectra were recorded 50m above the ground with 0.65 m vertical field of view. The second and third spectrometers were recorded with the Princeton ProEM camera and had a resolution of 0.5 Angstroms. These spectra were recorded 50m above ground with 0.06 m vertical field of view. The evolution of important lines in the spectral ranges such as singly ionized nitrogen lines (including spatially resolved 4630 Angstrom multiplet), H-alpha, and a resolved 7774 Angstrom Neutral oxygen triplet will all be presented. The opacity of the lightning channel as well as number density, temperature, and conductivity, will be discussed along with channel base current.

  17. High Resolution Spectroscopy to Support Atmospheric Measurements

    NASA Technical Reports Server (NTRS)

    Venkataraman, Malathy Devi

    2003-01-01

    Spectroscopic parameters (such as line position, intensity, broadening and shifting coefficients and their temperature dependences, line mixing coefficients etc.) for various molecular species of atmospheric interest are determined. In order to achieve these results, infrared spectra of several molecular bands are obtained using high-resolution recording instruments such as tunable diode laser spectrometer and Fourier transform spectrometers. Using sophisticated analysis routines (Multispectrum nonlinear least squares technique) these high-resolution infrared spectra are processed to determine the various spectral line parameters that are cited above. Spectra were taken using the McMath-Pierce Fourier transform spectrometer (FTS) at the National Solar Observatory on Kitt Peak, Arizona as well as the Bruker FTS at the Pacific Northwest National Laboratory (PNNL) at Richland, Washington. Most of the spectra are acquired not only at room temperature, but also at several different cold temperatures. This procedure is necessary to study the variation of the spectral line parameters as a function of temperature in order to simulate the Earth's and other planetary atmospheric environments. Depending upon the strength or weakness of the various bands recorded and analyzed, the length(s) of the absorption cells in which the gas samples under study are kept varied from a few centimeters up to several meters and the sample temperatures varied from approximately +30 C to -63 C. Research on several infrared bands of various molecular species and their isotopomers are undertaken. Those studies are briefly described.

  18. High Resolution Spectroscopy to Support Atmospheric Measurements

    NASA Technical Reports Server (NTRS)

    Benner, D. Chris; Venkataraman, Malathy Devi

    2000-01-01

    The major research activities performed during the cooperative agreement enhanced our spectroscopic knowledge of molecules of atmospheric interest such as carbon dioxide, water vapor, ozone, methane, and carbon monoxide, to name a few. Measurements were made using the NASA Langley Tunable Diode Laser Spectrometer System (TDL) and several Fourier Transform Spectrometer Systems (FTS) around the globe. The results from these studies made remarkable improvements in the line positions and intensities for several molecules, particularly ozone and carbon dioxide in the 2 to 17-micrometer spectral region. Measurements of pressure broadening and pressure induced line shift coefficients and the temperature dependence of pressure broadening and pressure induced line shift coefficients for infrared transitions of ozone, methane, and water vapor were also performed. Results from these studies have been used for retrievals of stratospheric gas concentration profiles from data collected by several Upper Atmospheric Research satellite (UARS) infrared instruments as well as in the analysis of high resolution atmospheric spectra such as those acquired by space-based, ground-based, and various balloon- and aircraft-borne experiments. Our results made significant contributions in several updates of the HITRAN (HIgh resolution TRANsmission) spectral line parameters database. This database enjoys worldwide recognition in research involving diversified scientific fields.

  19. High Resolution Spectroscopy to Support Atmospheric Measurements

    NASA Technical Reports Server (NTRS)

    Benner, D. Chris; Venkataraman, Malathy Devi

    2000-01-01

    The major research activities performed during the cooperative agreement enhanced our spectroscopic knowledge of molecules of atmospheric interest such as carbon dioxide, water vapor, ozone, methane, and carbon monoxide, to name a few. Measurements were made using the NASA Langley Tunable Diode Laser Spectrometer System (TDL) and several Fourier Transform Spectrometer Systems (FTS) around the globe. The results from these studies made remarkable improvements in the line positions and intensities for several molecules, particularly ozone and carbon dioxide in the 2 to 17-micrometer spectral region. Measurements of pressure broadening and pressure induced line shift coefficients and the temperature dependence of pressure broadening and pressure induced line shift coefficients for infrared transitions of ozone, methane, and water vapor were also performed. Results from these studies have been used for retrievals of stratospheric gas concentration profiles from data collected by several Upper Atmospheric Research satellite (UARS) infrared instruments as well as in the analysis of high resolution atmospheric spectra such as those acquired by space-based, ground-based, and various balloon-and aircraft-borne experiments. Our results made significant contributions in several updates of the HITRAN (HIgh resolution TRANsmission) spectral line parameters database. This database enjoys worldwide recognition in research involving diversified scientific fields.

  20. 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.

  1. High-Resolution Scintimammography: A Pilot Study

    SciTech Connect

    Rachel F. Brem; Joelle M. Schoonjans; Douglas A. Kieper; Stan Majewski; Steven Goodman; Cahid Civelek

    2002-07-01

    This study evaluated a novel high-resolution breast-specific gamma camera (HRBGC) for the detection of suggestive breast lesions. Methods: Fifty patients (with 58 breast lesions) for whom a scintimammogram was clinically indicated were prospectively evaluated with a general-purpose gamma camera and a novel HRBGC prototype. The results of conventional and high-resolution nuclear studies were prospectively classified as negative (normal or benign) or positive (suggestive or malignant) by 2 radiologists who were unaware of the mammographic and histologic results. All of the included lesions were confirmed by pathology. Results: There were 30 benign and 28 malignant lesions. The sensitivity for detection of breast cancer was 64.3% (18/28) with the conventional camera and 78.6% (22/28) with the HRBGC. The specificity with both systems was 93.3% (28/30). For the 18 nonpalpable lesions, sensitivity was 55.5% (10/18) and 72.2% (13/18) with the general-purpose camera and the HRBGC, respectively. For lesions 1 cm, 7 of 15 were detected with the general-purpose camera and 10 of 15 with the HRBGC. Four lesions (median size, 8.5 mm) were detected only with the HRBGC and were missed by the conventional camera. Conclusion: Evaluation of indeterminate breast lesions with an HRBGC results in improved sensitivity for the detection of cancer, with greater improvement shown for nonpalpable and 1-cm lesions.

  2. High Resolution LTS-SQUID Microscopes

    NASA Astrophysics Data System (ADS)

    Baudenbacher, Franz; Peters, Nicholas; Wikswo, John

    2000-03-01

    We have developed a scanning superconducting quantum interference device (SQUID) microscope for imaging magnetic fields of room-temperature samples with sub-millimeter resolution. In our design, hand wound niobium pickup coils were coupled to commercially available low-temperature SQUID sensors. The SQUID sensor and the pickup coil are in the vacuum space of the cryostat separated typically less than 50μm by a thin sapphire window from the room-temperature sample. A computerized non-magnetic scanning stage with sub-micron resolution in combination with a tripod leveling system allows samples to be scanned within 10μm of the sapphire window. For a 20-turn 500μm diameter pickup coil, we achieved a field sensitivity of 350fT\\cdotHz-1/2 for frequencies above 1 Hz, and 1pT\\cdotHz-1/2 for a 10-turn 250mm coil. The SQUID microscope was used to image the distribution of time-dependent stimulus and action currents in anisotropic cardiac tissue, the remanent magnetization of the Martian meteorite ALH84001 during thermal demagnetisation, and the magnetic susceptibility of biogenic magnetite in the beak of homing pigeons.

  3. High-Resolution NMR Probe for Experiments at High Pressures

    NASA Astrophysics Data System (ADS)

    Ballard, L.; Reiner, C.; Jonas, J.

    A 300 MHz high-resolution, high-pressure NMR probe which operates in the pressure range of 1 bar to 9 kbar at temperatures of -30 to 100°C is described. Specialized novel design features of the probe are discussed and test spectra showing resolution better than 1 Hz (<3.0 × 10 -9) for 8 mm samples are presented. Potential biochemical applications of this probe are illustrated by experiments dealing with the pressure-induced unfolding of hen egg white lysozyme.

  4. High-resolution spectrometer for atmospheric studies

    NASA Astrophysics Data System (ADS)

    Di Carlo, Piero; Barone, Massimiliano; D'Altorio, Alfonso; Dari-Salisburgo, Cesare; Pietropaolo, Ermanno

    2009-08-01

    A high-resolution spectrometer (0.0014 nm at 313 nm) has been developed at the University of L'Aquila (Italy) for atmospheric spectroscopic studies. The layout, optics and software for the instrument control are described. Measurements of the mercury low-pressure lamp lines from 200 to 600 nm show the high performances of the spectrometer. Laboratory measurements of OH and NO2 spectrums demonstrate that the system could be used for cross-section measurements and to detect these species in the atmosphere. The first atmospheric application of the system was the observation of direct solar and sky spectrums that shows a filling-in of the sky lines due to rotational Raman scattering. The measurements have been done with clear and cloudy sky and in both there was a strong dependence of the filling-in from the solar zenith angle whereas no dependence from the wavelengths was evident at low solar zenith angles (less than 85°).

  5. Characterization of a high resolution transmission grating

    NASA Astrophysics Data System (ADS)

    Desauté, P.; Merdji, H.; Greiner, V.; Missalla, T.; Chenais-Popovics, C.; Troussel, P.

    2000-01-01

    Three 5000 lines/mm gold transmission gratings have been tested with the radiation from the Super-ACO synchrotron in the range 250 eV< E<850 eV. Typical results for the spectral dependence of the grating efficiency at different diffraction orders are presented. This grating theoretically built to have no second order exhibits second order as high as 15-20% of first order. The very thin 5000 L/mm gratings are supported by a larger grid which perturbs the recorded data by separating each order in three peaks. Fraunhofer diffraction of the support grid has been modelled and can explain this effect. The high resolution gratings were used to measure the harmonics of the beamline monochromator grating (550 L/mm) and to measure the emission and absorption of laser-produced plasmas in the XUV range.

  6. Ultra-high resolution computed tomography imaging

    DOEpatents

    Paulus, Michael J.; Sari-Sarraf, Hamed; Tobin, Jr., Kenneth William; Gleason, Shaun S.; Thomas, Jr., Clarence E.

    2002-01-01

    A method for ultra-high resolution computed tomography imaging, comprising the steps of: focusing a high energy particle beam, for example x-rays or gamma-rays, onto a target object; acquiring a 2-dimensional projection data set representative of the target object; generating a corrected projection data set by applying a deconvolution algorithm, having an experimentally determined a transfer function, to the 2-dimensional data set; storing the corrected projection data set; incrementally rotating the target object through an angle of approximately 180.degree., and after each the incremental rotation, repeating the radiating, acquiring, generating and storing steps; and, after the rotating step, applying a cone-beam algorithm, for example a modified tomographic reconstruction algorithm, to the corrected projection data sets to generate a 3-dimensional image. The size of the spot focus of the beam is reduced to not greater than approximately 1 micron, and even to not greater than approximately 0.5 microns.

  7. Hydrogen depth profiling with sub-nm resolution in high-resolution ERD

    NASA Astrophysics Data System (ADS)

    Kimura, Kenji; Nakajima, Kaoru; Imura, Hideki

    1998-05-01

    A depth resolution of 0.28 nm is obtained in a depth profile of hydrogen in silicon using a newly developed high-resolution elastic recoil detection (ERD) system. The system consists of a standard 90° sector magnetic spectrometer (energy resolution ˜0.1%) for high-resolution measurement and an electrostatic deflector for blocking scattered incident ions without disturbing the energy resolution. The system is very simple as compared with other high-resolution ERD systems and the data acquisition time is reasonably short.

  8. Unsupervised Feature Learning for High-Resolution Satellite Image Classification

    SciTech Connect

    Cheriyadat, Anil M

    2013-01-01

    The rich data provided by high-resolution satellite imagery allow us to directly model geospatial neighborhoods by understanding their spatial and structural patterns. In this paper we explore an unsupervised feature learning approach to model geospatial neighborhoods for classification purposes. While pixel and object based classification approaches are widely used for satellite image analysis, often these approaches exploit the high-fidelity image data in a limited way. In this paper we extract low-level features to characterize the local neighborhood patterns. We exploit the unlabeled feature measurements in a novel way to learn a set of basis functions to derive new features. The derived sparse feature representation obtained by encoding the measured features in terms of the learned basis function set yields superior classification performance. We applied our technique on two challenging image datasets: ORNL dataset representing one-meter spatial resolution satellite imagery representing five land-use categories and, UCMERCED dataset consisting of 21 different categories representing sub-meter resolution overhead imagery. Our results are highly promising and, in the case of UCMERCED dataset we outperform the best results obtained for this dataset. We show that our feature extraction and learning methods are highly effective in developing a detection system that can be used to automatically scan large-scale high-resolution satellite imagery for detecting large-facility.

  9. Pyramidal fractal dimension for high resolution images

    NASA Astrophysics Data System (ADS)

    Mayrhofer-Reinhartshuber, Michael; Ahammer, Helmut

    2016-07-01

    Fractal analysis (FA) should be able to yield reliable and fast results for high-resolution digital images to be applicable in fields that require immediate outcomes. Triggered by an efficient implementation of FA for binary images, we present three new approaches for fractal dimension (D) estimation of images that utilize image pyramids, namely, the pyramid triangular prism, the pyramid gradient, and the pyramid differences method (PTPM, PGM, PDM). We evaluated the performance of the three new and five standard techniques when applied to images with sizes up to 8192 × 8192 pixels. By using artificial fractal images created by three different generator models as ground truth, we determined the scale ranges with minimum deviations between estimation and theory. All pyramidal methods (PM) resulted in reasonable D values for images of all generator models. Especially, for images with sizes ≥1024 ×1024 pixels, the PMs are superior to the investigated standard approaches in terms of accuracy and computation time. A measure for the possibility to differentiate images with different intrinsic D values did show not only that the PMs are well suited for all investigated image sizes, and preferable to standard methods especially for larger images, but also that results of standard D estimation techniques are strongly influenced by the image size. Fastest results were obtained with the PDM and PGM, followed by the PTPM. In terms of absolute D values best performing standard methods were magnitudes slower than the PMs. Concluding, the new PMs yield high quality results in short computation times and are therefore eligible methods for fast FA of high-resolution images.

  10. Pyramidal fractal dimension for high resolution images.

    PubMed

    Mayrhofer-Reinhartshuber, Michael; Ahammer, Helmut

    2016-07-01

    Fractal analysis (FA) should be able to yield reliable and fast results for high-resolution digital images to be applicable in fields that require immediate outcomes. Triggered by an efficient implementation of FA for binary images, we present three new approaches for fractal dimension (D) estimation of images that utilize image pyramids, namely, the pyramid triangular prism, the pyramid gradient, and the pyramid differences method (PTPM, PGM, PDM). We evaluated the performance of the three new and five standard techniques when applied to images with sizes up to 8192 × 8192 pixels. By using artificial fractal images created by three different generator models as ground truth, we determined the scale ranges with minimum deviations between estimation and theory. All pyramidal methods (PM) resulted in reasonable D values for images of all generator models. Especially, for images with sizes ≥1024×1024 pixels, the PMs are superior to the investigated standard approaches in terms of accuracy and computation time. A measure for the possibility to differentiate images with different intrinsic D values did show not only that the PMs are well suited for all investigated image sizes, and preferable to standard methods especially for larger images, but also that results of standard D estimation techniques are strongly influenced by the image size. Fastest results were obtained with the PDM and PGM, followed by the PTPM. In terms of absolute D values best performing standard methods were magnitudes slower than the PMs. Concluding, the new PMs yield high quality results in short computation times and are therefore eligible methods for fast FA of high-resolution images. PMID:27475069

  11. High-resolution colorimetric imaging of paintings

    NASA Astrophysics Data System (ADS)

    Martinez, Kirk; Cupitt, John; Saunders, David R.

    1993-05-01

    With the aim of providing a digital electronic replacement for conventional photography of paintings, a scanner has been constructed based on a 3000 X 2300 pel resolution camera which is moved precisely over a 1 meter square area. Successive patches are assembled to form a mosaic which covers the whole area at c. 20 pels/mm resolution, which is sufficient to resolve the surface textures, particularly craquelure. To provide high color accuracy, a set of seven broad-band interference filters are used to cover the visible spectrum. A calibration procedure based upon a least-mean-squares fit to the color of patches from a Macbeth Colorchecker chart yields an average color accuracy of better than 3 units in the CMC uniform color space. This work was mainly carried out as part of the VASARI project funded by the European Commission's ESPRIT program, involving companies and galleries from around Europe. The system is being used to record images for conservation research, for archival purposes and to assist in computer-aided learning in the field of art history. The paper will describe the overall system design, including the selection of the various hardware components and the design of controlling software. The theoretical basis for the color calibration methodology is described as well as the software for its practical implementation. The mosaic assembly procedure and some of the associated image processing routines developed are described. Preliminary results from the research will be presented.

  12. High resolution Fourier interferometer-spectrophotopolarimeter

    NASA Technical Reports Server (NTRS)

    Fymat, A. L. (Inventor)

    1976-01-01

    A high-resolution Fourier interferometer-spectrophotopolarimeter is provided using a single linear polarizer-analyzer the transmission axis azimuth of which is positioned successively in the three orientations of 0 deg, 45 deg, and 90 deg, in front of a detector; four flat mirrors, three of which are switchable to either of two positions to direct an incoming beam from an interferometer to the polarizer-analyzer around a sample cell transmitted through a medium in a cell and reflected by medium in the cell; and four fixed focussing lenses, all located in a sample chamber attached at the exit side of the interferometer. This arrangement can provide the distribution of energy and complete polarization state across the spectrum of the reference light entering from the interferometer; the same light after a fixed-angle reflection from the sample cell containing a medium to be analyzed; and the same light after direct transmission through the same sample cell, with the spectral resolution provided by the interferometer.

  13. Ultra-high resolution and high-brightness AMOLED

    NASA Astrophysics Data System (ADS)

    Wacyk, Ihor; Ghosh, Amal; Prache, Olivier; Draper, Russ; Fellowes, Dave

    2012-06-01

    As part of its continuing effort to improve both the resolution and optical performance of AMOLED microdisplays, eMagin has recently developed an SXGA (1280×3×1024) microdisplay under a US Army RDECOM CERDEC NVESD contract that combines the world's smallest OLED pixel pitch with an ultra-high brightness green OLED emitter. This development is aimed at next-generation HMD systems with "see-through" and daylight imaging requirements. The OLED pixel array is built on a 0.18-micron CMOS backplane and contains over 4 million individually addressable pixels with a pixel pitch of 2.7 × 8.1 microns, resulting in an active area of 0.52 inches diagonal. Using both spatial and temporal enhancement, the display can provide over 10-bits of gray-level control for high dynamic range applications. The new pixel design also enables the future implementation of a full-color QSXGA (2560 × RGB × 2048) microdisplay in an active area of only 1.05 inch diagonal. A low-power serialized low-voltage-differential-signaling (LVDS) interface is integrated into the display for use as a remote video link for tethered systems. The new SXGA backplane has been combined with the high-brightness green OLED device developed by eMagin under an NVESD contract. This OLED device has produced an output brightness of more than 8000fL with all pixels on; lifetime measurements are currently underway and will presented at the meeting. This paper will describe the operational features and first optical and electrical test results of the new SXGA demonstrator microdisplay.

  14. Clementine High Resolution Camera Mosaicking Project

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This report constitutes the final report for NASA Contract NASW-5054. This project processed Clementine I high resolution images of the Moon, mosaicked these images together, and created a 22-disk set of compact disk read-only memory (CD-ROM) volumes. The mosaics were produced through semi-automated registration and calibration of the high resolution (HiRes) camera's data against the geometrically and photometrically controlled Ultraviolet/Visible (UV/Vis) Basemap Mosaic produced by the US Geological Survey (USGS). The HiRes mosaics were compiled from non-uniformity corrected, 750 nanometer ("D") filter high resolution nadir-looking observations. The images were spatially warped using the sinusoidal equal-area projection at a scale of 20 m/pixel for sub-polar mosaics (below 80 deg. latitude) and using the stereographic projection at a scale of 30 m/pixel for polar mosaics. Only images with emission angles less than approximately 50 were used. Images from non-mapping cross-track slews, which tended to have large SPICE errors, were generally omitted. The locations of the resulting image population were found to be offset from the UV/Vis basemap by up to 13 km (0.4 deg.). Geometric control was taken from the 100 m/pixel global and 150 m/pixel polar USGS Clementine Basemap Mosaics compiled from the 750 nm Ultraviolet/Visible Clementine imaging system. Radiometric calibration was achieved by removing the image nonuniformity dominated by the HiRes system's light intensifier. Also provided are offset and scale factors, achieved by a fit of the HiRes data to the corresponding photometrically calibrated UV/Vis basemap, that approximately transform the 8-bit HiRes data to photometric units. The sub-polar mosaics are divided into tiles that cover approximately 1.75 deg. of latitude and span the longitude range of the mosaicked frames. Images from a given orbit are map projected using the orbit's nominal central latitude. Polar mosaics are tiled into squares 2250 pixels on a

  15. ALMA Debuts High-Resolution Results

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-07-01

    through space as it orbits the Sun. The resolution of these images — enough to study the shape and even some surface features of the asteroid! — are unprecedented for this wavelength. HL Tau is a young star surrounded by a protoplanetary disk. ALMA's detailed observations of this region revealed remarkable structure within the disk: a series of light and dark concentric rings indicative of planets caught in the act of forming. Studying this system will help us understand how multi-planet solar systems like our own form and evolve. The star-forming galaxy SDP.81 — located so far away that the light we see was emitted when the Universe was only 15% of its current age — is gravitationally-lensed into a cosmic arc, due to the convenient placement of a nearby foreground galaxy. The combination of the lucky alignment and ALMA's high resolution grant us a spectacularly detailed view of this distant galaxy, allowing us to study its actual shape and the motion within it. The observations from ALMA's first test of its long baseline demonstrate that ALMA is capable of doing the transformational science it promised. As we gear up for the next cycle of observations, it's clear that exciting times are ahead! Citation: ALMA ship et al. 2015 ApJ 808 L1, L2, L3 and L4. Focus on the ALMA Long Baseline Campaign

  16. ON THE IMPACT OF SUPER RESOLUTION WSR-88D DOPPLER RADAR DATA ASSIMILATION ON HIGH RESOLUTION NUMERICAL MODEL FORECASTS

    SciTech Connect

    Chiswell, S

    2009-01-11

    Assimilation of radar velocity and precipitation fields into high-resolution model simulations can improve precipitation forecasts with decreased 'spin-up' time and improve short-term simulation of boundary layer winds (Benjamin, 2004 & 2007; Xiao, 2008) which is critical to improving plume transport forecasts. Accurate description of wind and turbulence fields is essential to useful atmospheric transport and dispersion results, and any improvement in the accuracy of these fields will make consequence assessment more valuable during both routine operation as well as potential emergency situations. During 2008, the United States National Weather Service (NWS) radars implemented a significant upgrade which increased the real-time level II data resolution to 8 times their previous 'legacy' resolution, from 1 km range gate and 1.0 degree azimuthal resolution to 'super resolution' 250 m range gate and 0.5 degree azimuthal resolution (Fig 1). These radar observations provide reflectivity, velocity and returned power spectra measurements at a range of up to 300 km (460 km for reflectivity) at a frequency of 4-5 minutes and yield up to 13.5 million point observations per level in super-resolution mode. The migration of National Weather Service (NWS) WSR-88D radars to super resolution is expected to improve warning lead times by detecting small scale features sooner with increased reliability; however, current operational mesoscale model domains utilize grid spacing several times larger than the legacy data resolution, and therefore the added resolution of radar data is not fully exploited. The assimilation of super resolution reflectivity and velocity data into high resolution numerical weather model forecasts where grid spacing is comparable to the radar data resolution is investigated here to determine the impact of the improved data resolution on model predictions.

  17. Characterisation of ship diesel primary particulate matter at the molecular level by means of ultra-high-resolution mass spectrometry coupled to laser desorption ionisation--comparison of feed fuel, filter extracts and direct particle measurements.

    PubMed

    Rüger, Christopher P; Sklorz, Martin; Schwemer, Theo; Zimmermann, Ralf

    2015-08-01

    In this study, positive-mode laser desorption-ionisation ultra-high-resolution mass spectrometry (LDI-FT-ICR-MS) was applied to study combustion aerosol samples obtained from a ship diesel engine as well as the feed fuel, used to operate the engine. Furthermore, particulate matter was sampled from the exhaust tube using an impactor and analysed directly from the impaction foil without sample treatment. From the high percentage of shared sum formula as well as similarities in the chemical spread of aerosol and heavy fuel oil, results indicate that the primary aerosol mainly consists of survived, unburned species from the feed fuel. The effect of pyrosynthesis could be observed and was slightly more pronounced for the CH-class compared to other compound classes, but in summary not dominant. Alkylation pattern as well as the aromaticity distribution, using the double bond equivalent, revealed a shift towards lower alkylation state for the aerosol. The alkylation pattern of the most dominant series revealed a higher correlation between different aerosol samples than between aerosol and feed samples. This was confirmed by cluster analysis. Overall, this study shows that LDI-FT-ICR-MS can be successfully applied for the analysis of combustion aerosol at the molecular level and that sum formula information can be used to identify chemical differences between aerosol and fuel as well as between different size fractions of the particulate matter. PMID:25585886

  18. High spectral resolution remote sensing of canopy chemistry

    NASA Technical Reports Server (NTRS)

    Aber, John D.; Martin, Mary E.

    1995-01-01

    Near infrared laboratory spectra have been used for many years to determine nitrogen and lignin concentrations in plant materials. In recent years, similar high spectral resolution visible and infrared data have been available via airborne remote sensing instruments. Using data from NASA's Airborne visible/Infrared Imaging Spectrometer (AVIRIS) we attempt to identify spectral regions correlated with foliar chemistry at the canopy level in temperate forests.

  19. LandScan 2013 High Resolution Global Population Data Set

    Energy Science and Technology Software Center (ESTSC)

    2014-07-01

    The LandScan data set is a worldwide population database compiled on a 30"x30" latitude/longitude grid. Census counts (at sub-national level) were apportioned to each grid cell based on likelihood coefficients, which are based on land cover, slope, road proximity, high-resolution imagery, and other data sets. The LandScan data set was developed as part of Oak Ridge National Laboratory (ORNL) Global Population Project for estimating ambient populations at risk.

  20. A high resolution, adjustable, lockable laser mirror mount

    NASA Technical Reports Server (NTRS)

    Chadwick, C. H.

    1976-01-01

    A prototype high resolution, adjustable, lockable mirror mount is described, suitable for use as a resonator end mirror mount in fieldable lasers. The prototype was vibrated to 15g levels, 10-2000 Hz, and was shown to be stable to within 1 arc second and settable to an accuracy of 10 arc seconds. Improvements to be made to the prototype are outlined which will significantly improve the accuracy without sacrificing the other attributes of the prototype.

  1. Potential High Resolution Dosimeters For MRT

    NASA Astrophysics Data System (ADS)

    Bräuer-Krisch, E.; Rosenfeld, A.; Lerch, M.; Petasecca, M.; Akselrod, M.; Sykora, J.; Bartz, J.; Ptaszkiewicz, M.; Olko, P.; Berg, A.; Wieland, M.; Doran, S.; Brochard, T.; Kamlowski, A.; Cellere, G.; Paccagnella, A.; Siegbahn, E. A.; Prezado, Y.; Martinez-Rovira, I.; Bravin, A.; Dusseau, L.; Berkvens, P.

    2010-07-01

    Microbeam Radiation Therapy (MRT) uses highly collimated, quasi-parallel arrays of X-ray microbeams of 50-600 keV, produced by 2nd and 3rd generation synchrotron sources, such as the National Synchrotron Light Source (NSLS) in the U.S., and the European Synchrotron Radiation Facility (ESRF) in France, respectively. High dose rates are necessary to deliver therapeutic doses in microscopic volumes, to avoid spreading of the microbeams by cardiosynchronous movement of the tissues. A small beam divergence and a filtered white beam spectrum in the energy range between 30 and 250 keV results in the advantage of steep dose gradients with a sharper penumbra than that produced in conventional radiotherapy. MRT research over the past 20 years has allowed a vast number of results from preclinical trials on different animal models, including mice, rats, piglets and rabbits. Microbeams in the range between 10 and 100 micron width show an unprecedented sparing of normal radiosensitive tissues as well as preferential damage to malignant tumor tissues. Typically, MRT uses arrays of narrow (˜25-100 micron-wide) microplanar beams separated by wider (100-400 microns centre-to-centre, c-t-c) microplanar spaces. We note that thicker microbeams of 0.1-0.68 mm used by investigators at the NSLS are still called microbeams, although some invesigators in the community prefer to call them minibeams. This report, however, limits it discussion to 25-100 μm microbeams. Peak entrance doses of several hundreds of Gy are surprisingly well tolerated by normal tissues. High resolution dosimetry has been developed over the last two decades, but typical dose ranges are adapted to dose delivery in conventional Radiation Therapy (RT). Spatial resolution in the sub-millimetric range has been achieved, which is currently required for quality assurance measurements in Gamma-knife RT. Most typical commercially available detectors are not suitable for MRT applications at a dose rate of 16000 Gy/s, micron

  2. High-resolution Martian atmosphere modeling

    NASA Technical Reports Server (NTRS)

    Egan, W. G.; Fischbein, W. L.; Smith, L. L.; Hilgeman, T.

    1980-01-01

    A multilayer radiative transfer, high-spectral-resolution infrared model of the lower atmosphere of Mars has been constructed to assess the effect of scattering on line profiles. The model takes into accout aerosol scattering and absorption and includes a line-by-line treatment of scattering and absorption by CO2 and H2O. The aerosol complex indices of refraction used were those measured on montmorillonite and basalt chosen on the basis of Mars ir data from the NASA Lear Airborne Observatory. The particle sizes and distribution were estimated using Viking data. The molecular line treatment employs the AFGL line parameters and Voigt profiles. The modeling results indicate that the line profiles are only slightly affected by normal aerosol scattering and absorption, but the effect could be appreciable for heavy loading. The technique described permits a quantitative approach to assessing and correcting for the effect of aerosols on lineshapes in planetary atmospheres.

  3. Internal reflection sensors with high angular resolution

    NASA Astrophysics Data System (ADS)

    Shavirin, I.; Strelkov, O.; Vetskous, A.; Norton-Wayne, L.; Harwood, R.

    1996-07-01

    We discuss the use of total internal reflection for the production of sensors with high angular resolution. These sensors are intended for measurement of the angle between a sensor's axis and the direction to a source of radiation or reflecting object. Sensors of this type are used in controlling the position of machine parts in robotics and industry, orienting space vehicles and astronomic devices in relation to the Sun, and as autocollimators for checking angles of deviation. This kind of sensor was used in the Apollo space vehicle some 20 years ago. Using photodetectors with linear and area CCD arrays has opened up new application possibilities for appropriately designed sensors. A generalized methodology is presented applicable to a wide range of tasks. Some modifications that can improve the performance of the basic design are described.

  4. Improved methods for high resolution electron microscopy

    NASA Astrophysics Data System (ADS)

    Taylor, J. R.

    1987-04-01

    Existing methods of making support films for high resolution transmission electron microscopy are investigated and novel methods are developed. Existing methods of fabricating fenestrated, metal reinforced specimen supports (microgrids) are evaluated for their potential to reduce beam induced movement of monolamellar crystals of C44H90 paraffin supported on thin carbon films. Improved methods of producing hydrophobic carbon films by vacuum evaporation, and improved methods of depositing well ordered monolamellar paraffin crystals on carbon films are developed. A novel technique for vacuum evaporation of metals is described which is used to reinforce microgrids. A technique is also developed to bond thin carbon films to microgrids with a polymer bonding agent. Unique biochemical methods are described to accomplish site specific covalent modification of membrane proteins. Protocols are given which covalently convert the carboxy terminus of papain cleaved bacteriorhodopsin to a free thiol.

  5. High resolution analysis of satellite gradiometry

    NASA Technical Reports Server (NTRS)

    Colombo, O. L.

    1989-01-01

    Satellite gravity gradiometry is a technique now under development which, by the middle of the next decade, may be used for the high resolution charting from space of the gravity field of the earth and, afterwards, of other planets. Some data analysis schemes are reviewed for getting detailed gravity maps from gradiometry on both a global and a local basis. It also presents estimates of the likely accuracies of such maps, in terms of normalized spherical harmonics expansions, both using gradiometry alone and in combination with data from a Global Positioning System (GPS) receiver carried on the same spacecraft. It compares these accuracies with those of current and future maps obtained from other data (conventional tracking, satellite-satellite tracking, etc.), and also with the spectra of various signals of geophysical interest.

  6. Potential High Resolution Dosimeters For MRT

    SciTech Connect

    Braeuer-Krisch, E.; Brochard, T.; Prezado, Y.; Bravin, A.; Berkvens, P.; Rosenfeld, A.; Lerch, M.; Petasecca, M.; Akselrod, M.; Sykora, J.; Bartz, J.; Ptaszkiewicz, M.; Olko, P.; Berg, A.; Wieland, M.; Doran, S.; Kamlowski, A.; Cellere, G.

    2010-07-23

    Microbeam Radiation Therapy (MRT) uses highly collimated, quasi-parallel arrays of X-ray microbeams of 50-600 keV, produced by 2nd and 3rd generation synchrotron sources, such as the National Synchrotron Light Source (NSLS) in the U.S., and the European Synchrotron Radiation Facility (ESRF) in France, respectively. High dose rates are necessary to deliver therapeutic doses in microscopic volumes, to avoid spreading of the microbeams by cardiosynchronous movement of the tissues. A small beam divergence and a filtered white beam spectrum in the energy range between 30 and 250 keV results in the advantage of steep dose gradients with a sharper penumbra than that produced in conventional radiotherapy. MRT research over the past 20 years has allowed a vast number of results from preclinical trials on different animal models, including mice, rats, piglets and rabbits. Microbeams in the range between 10 and 100 micron width show an unprecedented sparing of normal radiosensitive tissues as well as preferential damage to malignant tumor tissues. Typically, MRT uses arrays of narrow ({approx}25-100 micron-wide) microplanar beams separated by wider (100-400 microns centre-to-centre, c-t-c) microplanar spaces. We note that thicker microbeams of 0.1-0.68 mm used by investigators at the NSLS are still called microbeams, although some invesigators in the community prefer to call them minibeams. This report, however, limits it discussion to 25-100 {mu}m microbeams. Peak entrance doses of several hundreds of Gy are surprisingly well tolerated by normal tissues. High resolution dosimetry has been developed over the last two decades, but typical dose ranges are adapted to dose delivery in conventional Radiation Therapy (RT). Spatial resolution in the sub-millimetric range has been achieved, which is currently required for quality assurance measurements in Gamma-knife RT. Most typical commercially available detectors are not suitable for MRT applications at a dose rate of 16000 Gy

  7. Limits of simulation based high resolution EBSD.

    PubMed

    Alkorta, Jon

    2013-08-01

    High resolution electron backscattered diffraction (HREBSD) is a novel technique for a relative determination of both orientation and stress state in crystals through digital image correlation techniques. Recent works have tried to use simulated EBSD patterns as reference patterns to achieve the absolute orientation and stress state of crystals. However, a precise calibration of the pattern centre location is needed to avoid the occurrence of phantom stresses. A careful analysis of the projective transformation involved in the formation of EBSD patterns has permitted to understand these phantom stresses. This geometrical analysis has been confirmed by numerical simulations. The results indicate that certain combinations of crystal strain states and sample locations (pattern centre locations) lead to virtually identical EBSD patterns. This ambiguity makes the problem of solving the absolute stress state of a crystal unfeasible in a single-detector configuration. PMID:23676453

  8. Improved methods for high resolution electron microscopy

    SciTech Connect

    Taylor, J.R.

    1987-04-01

    Existing methods of making support films for high resolution transmission electron microscopy are investigated and novel methods are developed. Existing methods of fabricating fenestrated, metal reinforced specimen supports (microgrids) are evaluated for their potential to reduce beam induced movement of monolamellar crystals of C/sub 44/H/sub 90/ paraffin supported on thin carbon films. Improved methods of producing hydrophobic carbon films by vacuum evaporation, and improved methods of depositing well ordered monolamellar paraffin crystals on carbon films are developed. A novel technique for vacuum evaporation of metals is described which is used to reinforce microgrids. A technique is also developed to bond thin carbon films to microgrids with a polymer bonding agent. Unique biochemical methods are described to accomplish site specific covalent modification of membrane proteins. Protocols are given which covalently convert the carboxy terminus of papain cleaved bacteriorhodopsin to a free thiol. 53 refs., 19 figs., 1 tab.

  9. High Spatial Resolution Spectroscopy of Semiconductor Nanostructures

    NASA Astrophysics Data System (ADS)

    Harris, Timothy D.; Gershoni, David; Pfeiffer, Loren N.

    1996-03-01

    Several recent reports employing high spatial resolution have revealed the dominance of exciton localization in the low temperature luminescence of semiconductor quantum structures.^[1-3] Understanding this localization is of critical importance for the reliable studies of low dimensional structures such as quantum wells, quantum wires and quantum dots. We report on low temperature and high spatial resolution photoluminescence and photoluminescence excitation studies of cleaved edge overgrown (CEO) single quantum wires. These samples permit the direct and unambiguous comparison between the optical properties of a (100) oriented quantum well, a (110) oriented quantum well, and the quantum wire which is formed at their intersection. Using low temperature near field optical spectroscopy, and a novel diffraction limited far field apparatus, we determine the carrier diffusion length dependence on pump wavelength and sample temperature in both the 2d systems and the genuinely 1D wire system. We also measure the absorption strength of the 1D system and find it to be a factor of 3 stronger than the absorption of the associated 2D systems.^[2] Using low temperature near field optical spectroscopy, and a novel diffraction limited far field apparatus, we also determine the carrier diffusion length dependence on pump wavelength and sample temperature. ^[1] H. F. Hess, E. Betzig, T. D. Harris, L. N. Pfeiffer, and K. W. West, Science 264, 1740 (1994). ^[2] T. D. Harris, D. Gershoni, R. D. Grober, L. Pfeiffer, K. West, and N. Chand, Appl. Phys. Lett, in press (1996) ^[3] D. Gammon, E. S. Snow, and D. S. Katzer, Appl. Phys. Lett. 67, 2391 (1995)

  10. High Resolution Spectroscopy to Support Atmospheric Measurements

    NASA Technical Reports Server (NTRS)

    Venkataraman, Malathy Devi

    2006-01-01

    The major research activities performed during the cooperative agreement enhanced our spectroscopic knowledge of molecules of atmospheric interest such as H2O (water vapor), O3 (ozone), HCN (hydrogen cyanide), CH4 (methane), NO2 (nitrogen dioxide) and CO (carbon monoxide). The data required for the analyses were obtained from two different Fourier Transform Spectrometers (FTS); one of which is located at the National Solar Observatory (NSO) on Kitt Peak, Arizona and the other instrument is located at the Pacific Northwest National Laboratories (PNNL) at Richland, Washington. The data were analyzed using a modified multispectrum nonlinear least squares fitting algorithm developed by Dr. D. Chris Benner of the College of William and Mary. The results from these studies made significant improvements in the line positons and intensities for these molecules. The measurements of pressure broadening and pressure induced line shift coefficients and the temperature dependence of pressure broadening and pressure induced shift coefficients for hundreds of infrared transitions of HCN, CO3 CH4 and H2O were also performed during this period. Results from these studies have been used for retrievals of stratospheric gas concentration profiles from data collected by several Upper Atmospheric Research Satellite (UARS) infrared instruments as well as in the analysis of high resolution atmospheric spectra such as those acquired by space-based, ground-based, and various balloon- and aircraft-borne experiments. Our results made significant contributions in several updates of the HITRAN (HIgh resolution TRANsmission) spectral line parameters database. This database enjoys worldwide recognition in research involving diversified scientific fields. The research conducted during the period 2003-2006 has resulted in publications given in this paper. In addition to Journal publications, several oral and poster presentations were given at various Scientific conferences within the United States

  11. Ecological applications of high resolution spectrometry

    NASA Technical Reports Server (NTRS)

    Lawrence, William T.

    1989-01-01

    Future directions of NASA's space program plans include a significant effort at studying the Earth as a system of interrelated ecosystems. As part of NASA's Earth Observing System (Eos) Program a series of space platforms will be launched and operated to study the Earth with a variety of active and passive instruments. Several of the Eos instruments will be capable of imaging the planet's surface reflectance on a large number of very narrow portions of the solar spectrum. After the development of appropriate algorithms, this reflectance information will be used to determine key parameters about the structure and function of terrestrial and aquatic ecosystems and the pattern and processes of those systems across large areas of the globe. Algorithm development applicable to terrestrial systems will permit the inference of ecological processes from high resolution spectrometry data, similar to that to be forthcoming from the Eos mission. The first summer was spent working with tropical soils and relating their reflectance characteristics to particle size, iron content, and color. This summer the emphasis is on vegetation and work was begun with the Forest Ecosystems Dynamics Project in the Earth Resources Branch where both optical and radar characteristics of a mixed conifer/hardwood forest in Maine are being studied for use in a ecological modeling effort. A major series of aircraft overflights will take place throughout the summer. Laboratory and field spectrometers are used to measure the spectral reflectance of a hierarchy of vegetation from individual leaves to whole canopies for eventual modeling of their nutrient content using reflectance data. Key leaf/canopy parameters are being approximated including chlorophyll, nitrogen, phosphorus, water content, and leaf specific weight using high resolution spectrometry alone. Measurements are made of carbon exchange across the landscape for input to a spatial modeling effort to gauge production within the forest. A

  12. A high resolution global scale groundwater model

    NASA Astrophysics Data System (ADS)

    de Graaf, I. E.; Sutanudjaja, E.; Van Beek, L. P.; Bierkens, M. F.

    2013-12-01

    As the world's largest accessible source of freshwater, groundwater plays a vital role in satisfying the basic needs of human society. It serves as a primary source of drinking water and also supplies water for agricultural and industrial activities. During times of drought, the large natural groundwater storage provides a buffer against water shortage and sustains flows to rivers and wetlands, supporting ecosystem habitats and biodiversity. Yet, the current generation of global scale hydrological models (GHMs) do not include a groundwater flow component, although it is a crucial part of the hydrological cycle. Thus, a realistic physical representation of the groundwater system that allows for the simulation of groundwater head dynamics and lateral flows is essential for GHMs that increasingly run at finer resolution. In this study we present a transient global groundwater model with a resolution of 5 arc-minutes (approximately 10 km at the equator) using MODFLOW (McDonald and Harbaugh, 1988). Aquifer schematization and properties of this groundwater model were developed from available global lithological maps and datasets (Dürr et al., 2005; Gleeson et al., 2010; Hartmann and Moosdorf, 2013) combined with information about e.g. aquifer thickness and presence of less permeable, impermeable, and semi-impermeable layers. For the parameterization, we relied entirely on available global datasets and did not calibrate the model so that it can equally be expanded to data poor environments. We forced the groundwater model with the output from the global hydrological model PCR-GLOBWB (van Beek et al., 2011), specifically the net groundwater recharge and average surface water levels derived from routed channel discharge. We validated simulated groundwater heads with observations, from North America and Australia, resulting in a coefficient of determination of 0.8 and 0.7 respectively. This shows that it is feasible to build a global groundwater model using best available

  13. A high resolution solar atlas for fluorescence calculations

    NASA Technical Reports Server (NTRS)

    Hearn, M. F.; Ohlmacher, J. T.; Schleicher, D. G.

    1983-01-01

    The characteristics required of a solar atlas to be used for studying the fluorescence process in comets are examined. Several sources of low resolution data were combined to provide an absolutely calibrated spectrum from 2250 A to 7000A. Three different sources of high resolution data were also used to cover this same spectral range. The low resolution data were then used to put each high resolution spectrum on an absolute scale. The three high resolution spectra were then combined in their overlap regions to produce a single, absolutely calibrated high resolution spectrum over the entire spectral range.

  14. Wavefront metrology for high resolution optical systems

    NASA Astrophysics Data System (ADS)

    Miyakawa, Ryan H.

    Next generation extreme ultraviolet (EUV) optical systems are moving to higher resolution optics to accommodate smaller length scales targeted by the semiconductor industry. As the numerical apertures (NA) of the optics become larger, it becomes increasingly difficult to characterize aberrations due to experimental challenges associated with high-resolution spatial filters and geometrical effects caused by large incident angles of the test wavefront. This dissertation focuses on two methods of wavefront metrology for high resolution optical systems. The first method, lateral shearing interferometry (LSI), is a self-referencing interferometry where the test wavefront is incident on a low spatial frequency grating, and the resulting interference between the diffracted orders is used to reconstruct the wavefront aberrations. LSI has many advantages over other interferometric tests such as phase-shifting point diffraction interferometry (PS/PDI) due to its experimental simplicity, stability, relaxed coherence requirements, and its ability to scale to high numerical apertures. While LSI has historically been a qualitative test, this dissertation presents a novel quantitative investigation of the LSI interferogram. The analysis reveals the existence of systematic aberrations due to the nonlinear angular response from the diffraction grating that compromises the accuracy of LSI at medium to high NAs. In the medium NA regime (0.15 < NA < 0.35), a holographic model is presented that derives the systematic aberrations in closed form, which demonstrates an astigmatism term that scales as the square of the grating defocus. In the high NA regime (0.35 < NA), a geometrical model is introduced that describes the aberrations as a system of transcendental equations that can be solved numerically. The characterization and removal of these systematic errors is a necessary step that unlocks LSI as a viable candidate for high NA EUV optical testing. The second method is a novel image

  15. The HFIP High Resolution Hurricane Forecast Test

    NASA Astrophysics Data System (ADS)

    Nance, L. B.; Bernardet, L.; Bao, S.; Brown, B.; Carson, L.; Fowler, T.; Halley Gotway, J.; Harrop, C.; Szoke, E.; Tollerud, E. I.; Wolff, J.; Yuan, H.

    2010-12-01

    Tropical cyclones are a serious concern for the nation, causing significant risk to life, property and economic vitality. The National Oceanic and Atmospheric Administration (NOAA) National Weather Service has a mission of issuing tropical cyclone forecasts and warnings, aimed at protecting life and property and enhancing the national economy. In the last 10 years, the errors in hurricane track forecasts have been reduced by about 50% through improved model guidance, enhanced observations, and forecaster expertise. However, little progress has been made during this period toward reducing forecasted intensity errors. To address this shortcoming, NOAA established the Hurricane Forecast Improvement Project (HFIP) in 2007. HFIP is a 10-year plan to improve one to five day tropical cyclone forecasts, with a focus on rapid intensity change. Recent research suggests that prediction models with grid spacing less than 1 km in the inner core of the hurricane may provide a substantial improvement in intensity forecasts. The 2008-09 staging of the High Resolution Hurricane (HRH) Test focused on quantifying the impact of increased horizontal resolution in numerical models on hurricane intensity forecasts. The primary goal of this test was an evaluation of the effect of increasing horizontal resolution within a given model across a variety of storms with different intensity, location and structure. The test focused on 69 retrospectives cases from the 2005 and 2007 hurricane seasons. Six modeling groups participated in the HRH test utilizing a variety of models, including three configurations of the Weather Research and Forecasting (WRF) model, the operational GFDL model, the Navy’s tropical cyclone model, and a model developed at the University of Wisconsin-Madison (UWM). The Development Testbed Center (DTC) was tasked with providing objective verification statistics for a variety of metrics. This presentation provides an overview of the HRH Test and a summary of the standard

  16. High resolution electron attachment to CO₂ clusters.

    PubMed

    Denifl, Stephan; Vizcaino, Violaine; Märk, Tilmann D; Illenberger, Eugen; Scheier, Paul

    2010-01-01

    Electron attachment to CO₂ clusters performed at high energy resolution (0.1 eV) is studied for the first time in the extended electron energy range from threshold (0 eV) to about 10 eV. Dissociative electron attachment (DEA) to single molecules yields O(-) as the only fragment ion arising from the well known (2)Π(u) shape resonance (ion yield centered at 4.4 eV) and a core excited resonance (at 8.2 eV). On proceeding to CO₂ clusters, non-dissociated complexes of the form (CO₂)(n)(-) including the monomer CO₂(-) are generated as well as solvated fragment ions of the form (CO₂)(n)O(-). The non-decomposed complexes appear already within a resonant feature near threshold (0 eV) and also within a broad contribution between 1 and 4 eV which is composed of two resonances observed for example for (CO₂)(4)(-) at 2.2 eV and 3.1 eV (peak maxima). While the complexes observed around 3.1 eV are generated via the (2)Π(u) resonance as precursor with subsequent intracluster relaxation, the contribution around 2.2 eV can be associated with a resonant scattering feature, recently discovered in single CO₂ in the selective excitation of the higher energy member of the well known Fermi dyad [M. Allan, Phys. Rev. Lett., 2001, 87, 0332012]. Formation of (CO₂)(n)(-) in the threshold region involves vibrational Feshbach resonances (VFRs) as previously discovered via an ultrahigh resolution (1 meV) laser photoelectron attachment method [E. Leber, S. Barsotti, I. I. Fabrikant, J. M. Weber, M.-W. Ruf and H. Hotop, Eur. Phys. J. D, 2000, 12, 125]. The complexes (CO₂)(n)O(-) clearly arise from DEA at an individual molecule within the cluster involving both the (2)Π(u) and the core excited resonance. PMID:21491691

  17. Decadal prediction with a high resolution model

    NASA Astrophysics Data System (ADS)

    Monerie, Paul-Arthur; Valcke, Sophie; Terray, Laurent; Moine, Marie-Pierre

    2016-04-01

    The ability of a high resolution coupled atmosphere-ocean general circulation model (with a horizontal resolution of the quarter degree in the ocean and of about 50 km in the atmosphere) to predict the annual means of temperature, precipitation, sea-ice volume and extent is assessed. Reasonable skill in predicting sea surface temperatures and surface air temperature is obtained, especially over the North Atlantic, the tropical Atlantic and the Indian Ocean. The skill in predicting precipitations is weaker and not significant. The Sea Ice Extent and volume are also reasonably predicted in winter (March) and summer (September). It is however argued that the skill is mainly due to the atmosphere feeding in well-mixed GHGs. The mid-90's subpolar gyre warming is assessed. The model simulates a warming of the North Atlantic Ocean, associated with an increase of the meridional heat transport, a strengthening of the North Atlantic current and a deepening of the mixed layer over the Labrador Sea. The atmosphere plays a role in the warming through a modulation of the North Atlantic Oscillation and a shrinking of the subpolar gyre. At the 3-8 years lead-time, a negative anomaly of pressure, located south of the subpolar gyre is associated with the wind speed decrease over the subpolar gyre. It prevents oceanic heat-loss and favors the northward move, from the subtropical to the subpolar gyre, of anomalously warm and salty water, leading to its warming. We finally argued that the subpolar gyre warming is triggered by the ocean dynamic but the atmosphere can contributes to its sustaining. This work is realised in the framework of the EU FP7 SPECS Project.

  18. Toward high-resolution optoelectronic retinal prosthesis

    NASA Astrophysics Data System (ADS)

    Palanker, Daniel; Huie, Philip; Vankov, Alexander; Asher, Alon; Baccus, Steven

    2005-04-01

    It has been already demonstrated that electrical stimulation of retina can produce visual percepts in blind patients suffering from macular degeneration and retinitis pigmentosa. Current retinal implants provide very low resolution (just a few electrodes), while several thousand pixels are required for functional restoration of sight. We present a design of the optoelectronic retinal prosthetic system that can activate a retinal stimulating array with pixel density up to 2,500 pix/mm2 (geometrically corresponding to a visual acuity of 20/80), and allows for natural eye scanning rather than scanning with a head-mounted camera. The system operates similarly to "virtual reality" imaging devices used in military and medical applications. An image from a video camera is projected by a goggle-mounted infrared LED-LCD display onto the retina, activating an array of powered photodiodes in the retinal implant. Such a system provides a broad field of vision by allowing for natural eye scanning. The goggles are transparent to visible light, thus allowing for simultaneous utilization of remaining natural vision along with prosthetic stimulation. Optical control of the implant allows for simple adjustment of image processing algorithms and for learning. A major prerequisite for high resolution stimulation is the proximity of neural cells to the stimulation sites. This can be achieved with sub-retinal implants constructed in a manner that directs migration of retinal cells to target areas. Two basic implant geometries are described: perforated membranes and protruding electrode arrays. Possibility of the tactile neural stimulation is also examined.

  19. High Resolution Airborne Shallow Water Mapping

    NASA Astrophysics Data System (ADS)

    Steinbacher, F.; Pfennigbauer, M.; Aufleger, M.; Ullrich, A.

    2012-07-01

    In order to meet the requirements of the European Water Framework Directive (EU-WFD), authorities face the problem of repeatedly performing area-wide surveying of all kinds of inland waters. Especially for mid-sized or small rivers this is a considerable challenge imposing insurmountable logistical efforts and costs. It is therefore investigated if large-scale surveying of a river system on an operational basis is feasible by employing airborne hydrographic laser scanning. In cooperation with the Bavarian Water Authority (WWA Weilheim) a pilot project was initiated by the Unit of Hydraulic Engineering at the University of Innsbruck and RIEGL Laser Measurement Systems exploiting the possibilities of a new LIDAR measurement system with high spatial resolution and high measurement rate to capture about 70 km of riverbed and foreland for the river Loisach in Bavaria/Germany and the estuary and parts of the shoreline (about 40km in length) of lake Ammersee. The entire area surveyed was referenced to classic terrestrial cross-section surveys with the aim to derive products for the monitoring and managing needs of the inland water bodies forced by the EU-WFD. The survey was performed in July 2011 by helicopter and airplane and took 3 days in total. In addition, high resolution areal images were taken to provide an optical reference, offering a wide range of possibilities on further research, monitoring, and managing responsibilities. The operating altitude was about 500 m to maintain eye-safety, even for the aided eye, the airspeed was about 55 kts for the helicopter and 75 kts for the aircraft. The helicopter was used in the alpine regions while the fixed wing aircraft was used in the plains and the urban area, using appropriate scan rates to receive evenly distributed point clouds. The resulting point density ranged from 10 to 25 points per square meter. By carefully selecting days with optimum water quality, satisfactory penetration down to the river bed was achieved

  20. Cortical Surface Reconstruction from High-Resolution MR Brain Images

    PubMed Central

    Osechinskiy, Sergey; Kruggel, Frithjof

    2012-01-01

    Reconstruction of the cerebral cortex from magnetic resonance (MR) images is an important step in quantitative analysis of the human brain structure, for example, in sulcal morphometry and in studies of cortical thickness. Existing cortical reconstruction approaches are typically optimized for standard resolution (~1 mm) data and are not directly applicable to higher resolution images. A new PDE-based method is presented for the automated cortical reconstruction that is computationally efficient and scales well with grid resolution, and thus is particularly suitable for high-resolution MR images with submillimeter voxel size. The method uses a mathematical model of a field in an inhomogeneous dielectric. This field mapping, similarly to a Laplacian mapping, has nice laminar properties in the cortical layer, and helps to identify the unresolved boundaries between cortical banks in narrow sulci. The pial cortical surface is reconstructed by advection along the field gradient as a geometric deformable model constrained by topology-preserving level set approach. The method's performance is illustrated on exvivo images with 0.25–0.35 mm isotropic voxels. The method is further evaluated by cross-comparison with results of the FreeSurfer software on standard resolution data sets from the OASIS database featuring pairs of repeated scans for 20 healthy young subjects. PMID:22481909

  1. Future trends in high-resolution lithography

    NASA Astrophysics Data System (ADS)

    Lawes, R. A.

    2000-02-01

    A perennial question is "what is the future of high-resolution lithography, a key technology that drives the semiconductor industry"? The dominant technology over the last 30 years has been optical lithography, which by lowering wavelengths to 193 nm (ArF) and 157 nm (F 2) and by using optical "tricks" such as phase shift masks, off-axis illumination and phase filters, should be capable of 100 nm CMOS technology. So where does this leave the competition? The 100-nm lithography used to be the domain of electron beam lithography but only in research laboratories. Significant efforts are being made to increase throughput by electron projection (scattering with angular limitation projection electron beam lithography or SCALPEL). X-ray lithography remains a demonstrated R&D tool waiting to be commercially exploited but the initial expenditure to do so is very high. Ion beam lithography and extreme ultraviolet (EUV) ( λ<12 nm) have also received attention in recent years. This paper will concentrate on some of the key issues and speculate on how and when an alternative to optical lithography will be embraced by industry.

  2. High Resolution Image Reconstruction from Projection of Low Resolution Images DIffering in Subpixel Shifts

    NASA Technical Reports Server (NTRS)

    Mareboyana, Manohar; Le Moigne-Stewart, Jacqueline; Bennett, Jerome

    2016-01-01

    In this paper, we demonstrate a simple algorithm that projects low resolution (LR) images differing in subpixel shifts on a high resolution (HR) also called super resolution (SR) grid. The algorithm is very effective in accuracy as well as time efficiency. A number of spatial interpolation techniques using nearest neighbor, inverse-distance weighted averages, Radial Basis Functions (RBF) etc. used in projection yield comparable results. For best accuracy of reconstructing SR image by a factor of two requires four LR images differing in four independent subpixel shifts. The algorithm has two steps: i) registration of low resolution images and (ii) shifting the low resolution images to align with reference image and projecting them on high resolution grid based on the shifts of each low resolution image using different interpolation techniques. Experiments are conducted by simulating low resolution images by subpixel shifts and subsampling of original high resolution image and the reconstructing the high resolution images from the simulated low resolution images. The results of accuracy of reconstruction are compared by using mean squared error measure between original high resolution image and reconstructed image. The algorithm was tested on remote sensing images and found to outperform previously proposed techniques such as Iterative Back Projection algorithm (IBP), Maximum Likelihood (ML), and Maximum a posterior (MAP) algorithms. The algorithm is robust and is not overly sensitive to the registration inaccuracies.

  3. Morphometric and high resolution scanning electron microscopy analysis of low-level laser therapy and latex protein (Hevea brasiliensis) administration following a crush injury of the sciatic nerve in rats.

    PubMed

    Dias, Fernando J; Issa, João Paulo M; Coutinho-Netto, Joaquim; Fazan, Valéria P S; Sousa, Luiz Gustavo; Iyomasa, Mamie M; Papa, Paula C; Watanabe, Ii-Sei

    2015-02-15

    This study evaluated the effect of low-level laser therapy (LLLT; 15 J/cm(2)) and a latex protein (F1) on a crush injury of the sciatic (ischiadicus) nerve. Seventy-two rats (male, 250 g) were divided into 6 groups: CG, control; EG, exposed nerve; IG, injured nerve without treatment; LG, injured nerve with LLLT; HG, injured nerve with F1; and LHG, injured nerve with LLLT and F1. After 4 or 8 weeks, the animals were euthanized and samples of the sciatic nerve were collected for morphometric and high-resolution scanning electron microscopy (HRSEM) analysis. After 4 weeks, the morphometry revealed improvements in the treated animals, and the HG appeared to be the most similar to the CG; after 8 weeks, the injured groups showed improvements compared to the previous period, and the results of the treatment groups were more similar to one another. At HRSEM after 4 weeks, the treated groups were similar and showed improvement compared to the IG; after 8 weeks, the LHG and HG had the best results. In conclusion, the treatments resulted in improvement after the nerve injury, and this recovery was time-dependent. In addition, the use of the F1 resulted in the best morphometric and ultrastructural findings. PMID:25619570

  4. High resolution coherent three dimensional spectroscopy of NO2.

    PubMed

    Wells, Thresa A; Muthike, Angelar K; Robinson, Jessica E; Chen, Peter C

    2015-06-01

    Expansion from coherent 2D spectroscopy to coherent 3D spectroscopy can provide significant advantages when studying molecules that have heavily perturbed energy levels. This paper illustrates such advantages by demonstrating how high resolution coherent 3D (HRC3D) spectroscopy can be used to study a portion of the visible spectrum of nitrogen dioxide. High resolution coherent 2D spectra usually contain rotational and vibrational patterns that are easy to analyze, but severe congestion and complexity preclude its effective use for many parts of the NO2 spectrum. HRC3D spectroscopy appears to be much more effective; multidimensional rotational and vibrational patterns produced by this new technique are easy to identify even in the presence of strong perturbations. A method for assigning peaks, which is based upon analyzing the resulting multidimensional patterns, has been developed. The higher level of multidimensionality is useful for reducing uncertainty in peak assignments, improving spectral resolution, providing simultaneous information on multiple levels and states, and predicting, verifying, and categorizing peaks. PMID:26049446

  5. High Resolution Magnetotail Simulations of Bursty Bulk Flows

    NASA Astrophysics Data System (ADS)

    Buzulukova, N.; Dorelli, J.; Glocer, A.; Fok, M. C. H.; Toth, G.

    2014-12-01

    We present the results of high resolution resistive MHD simulations of bursty bulk flows using the BATSRUS magnetosphere model. We performed a number of runs with three levels of constant resistivity. For each resistivity level, we studied the dependence on tail resolution and looked for solutions where numerical resistivity was small compared to the set physical resistivity. For constant solar wind driving (southward Bz IMF), we found the formation of bursty bulk flows (BBFs) and dipolarization fronts when the resistivity was below a critical value. We extracted virtual s/c data through dipolarization fronts and BBFs and compared with observed properties of BBFs. We also studied the ionospheric response to BBF formation. By switching on/off the ring current module (CRCM) in the BATSRUS, we examined relationship between BBFs and ring current injections.

  6. High-Resolution Multiphoton Imaging of Tumors In Vivo

    PubMed Central

    Wyckoff, Jeffrey; Gligorijevic, Bojana; Entenberg, David; Segall, Jeffrey; Condeelis, John

    2014-01-01

    Analysis of the individual steps in metastasis is crucial if insights at the molecular level are to be linked to the cell biology of cancer. A technical hurdle to achieving the analysis of the individual steps of metastasis is the fact that, at the gross level, tumors are heterogeneous in both animal models and patients. Human primary tumors show extensive variation in all properties ranging from growth and morphology of the tumor through tumor-cell density in the blood and formation and growth of metastases. Methods capable of the direct visualization and analysis of tumor-cell behavior at single-cell resolution in vivo have become crucial in advancing the understanding of mechanisms of metastasis, the definition of microenvironment, and the markers related to both. This article discusses the use of high-resolution multiphoton imaging of tumors (specifically breast tumors in mice) in vivo. PMID:21969629

  7. Updating Maps Using High Resolution Satellite Imagery

    NASA Astrophysics Data System (ADS)

    Alrajhi, Muhamad; Shahzad Janjua, Khurram; Afroz Khan, Mohammad; Alobeid, Abdalla

    2016-06-01

    Kingdom of Saudi Arabia is one of the most dynamic countries of the world. We have witnessed a very rapid urban development's which are altering Kingdom's landscape on daily basis. In recent years a substantial increase in urban populations is observed which results in the formation of large cities. Considering this fast paced growth, it has become necessary to monitor these changes, in consideration with challenges faced by aerial photography projects. It has been observed that data obtained through aerial photography has a lifecycle of 5-years because of delay caused by extreme weather conditions and dust storms which acts as hindrances or barriers during aerial imagery acquisition, which has increased the costs of aerial survey projects. All of these circumstances require that we must consider some alternatives that can provide us easy and better ways of image acquisition in short span of time for achieving reliable accuracy and cost effectiveness. The approach of this study is to conduct an extensive comparison between different resolutions of data sets which include: Orthophoto of (10 cm) GSD, Stereo images of (50 cm) GSD and Stereo images of (1 m) GSD, for map updating. Different approaches have been applied for digitizing buildings, roads, tracks, airport, roof level changes, filling stations, buildings under construction, property boundaries, mosques buildings and parking places.

  8. Road Extraction from High Resolution Satellite Images

    NASA Astrophysics Data System (ADS)

    Özkaya, M.

    2012-07-01

    Roads are significant objects of an infrastructure and the extraction of roads from aerial and satellite images are important for different applications such as automated map generation and change detection. Roads are also important to detect other structures such as buildings and urban areas. In this paper, the road extraction approach is based on Active Contour Models for 1-meter resolution gray level images. Active Contour Models contains Snake Approach. During applications, the road structure was separated as salient-roads, non-salient roads and crossings and extraction of these is provided by using Ribbon Snake and Ziplock Snake methods. These methods are derived from traditional snake model. Finally, various experimental results were presented. Ribbon and Ziplock Snake methods were compared for both salient and non-salient roads. Also these methods were used to extract roads in an image. While Ribbon snake is described for extraction of salient roads in an image, Ziplock snake is applied for extraction of non-salient roads. Beside these, some constant variables in literature were redefined and expressed in a formula as depending on snake approach and a new approach for extraction of crossroads were described and tried.

  9. A high resolution global scale groundwater model

    NASA Astrophysics Data System (ADS)

    de Graaf, I. E. M.; Sutanudjaja, E. H.; van Beek, L. P. H.; Bierkens, M. F. P.

    2014-05-01

    Groundwater is the world's largest accessible source of fresh water. It plays a vital role in satisfying needs for drinking water, agriculture and industrial activities. During times of drought groundwater sustains baseflow to rivers and wetlands, thereby supporting ecosystems. Most global scale hydrological models (GHMs) do not include a groundwater flow component, mainly due to lack of geohydrological data at the global scale. For the simulation of lateral flow and groundwater head dynamics a realistic physical representation of the groundwater system is needed, especially for GHMs that run at finer resolution. In this study we present a global scale groundwater model (run at 6' as dynamic steady state) using MODFLOW to construct an equilibrium water table at its natural state as the result of long-term climatic forcing. The aquifer schematization and properties were based on available global datasets of lithology and transmissivities combined with estimated aquifer thickness of an upper unconfined aquifer. The model is forced with outputs from the land-surface model PCR-GLOBWB, specifically with net recharge and surface water levels. A sensitivity analysis, in which the model was run with various parameter settings, showed variation in saturated conductivity causes most of the groundwater level variations. Simulated groundwater heads were validated against reported piezometer observations. The validation showed that groundwater depths are reasonably well simulated for many regions of the world, especially for sediment basins (R2 = 0.95). The simulated regional scale groundwater patterns and flowpaths confirm the relevance of taking lateral groundwater flow into account in GHMs. Flowpaths show inter-basin groundwater flow that can be a significant part of a basins water budget and helps to sustain river baseflow, explicitly during times of droughts. Also important aquifer systems are recharged by inter-basin groundwater flows that positively affect water

  10. High time resolution studies of upstream ions

    NASA Technical Reports Server (NTRS)

    Anderson, K. A.; Levedahl, W. K.; Lin, R. P.; Parks, G. K.

    1984-01-01

    The influence of phi, the angle between the interplanetary magnetic field and the earth-sun vector on ions and electrons in the earth's bow shock, was investigated in terms of ISEE 2 data. A small phi was associated with intermediate energy upstream ions and reduced populations of low energy, about 1.6 keV, ion fluxes. The magnitude of phi was closely related to particular, constant energy levels, e.g., a phi of 40 deg and an energy of 30 keV and a phi of 75 deg and an energy of 6 keV. Ion fluxes are high in the angles form 60-80 deg and feature energies of 55-280 keV. The acceleration process up to the high energy levels in the 1-3 min interval from upstream to downstream occurs more rapidly than could be accounted for by a first-order Fermi process.

  11. High resolution rainfall measurements around a high rise building

    NASA Astrophysics Data System (ADS)

    de Jong, Stijn; van de Giesen, Nick; Hut, Rolf

    2010-05-01

    A number of disdrometers (acoustic rain gauge) has been placed around a high rise building on a place where variation in spatial distribution of precipitation is expected, to show the advantage of high resolution rainfall measurements in a urban area. The standard recommendation for the placement of a rain gauge is that the gauge is positioned at a distance corresponding to two to four times the height of any nearby obstruction to obtain a measurement that is representative for the surrounding area. In an urban area it is almost impossible to find a location that suits this recommendation. Rain measurements in urban area with a high spatial resolution are desired, to obtain a better understanding of urban hydrology, but costs may be prohibitive. A low cost disdrometer has been developed to make it affordable to perform rain measurements with a very high spatial and temporal resolution. The disdrometer is tested around a high rise building on the Delft University of Technology campus. The faculty of Electrical Engineering, Mathematics and Computer Science (EWI) on the campus of Delft University of Technology consists of a high rise building of 90 meters and a low rise building of 15 meters. Sensors are placed on the low rise building to measure the impact of the high rise building on the spatial distribution of precipitation. In addition to the disdrometer, two other methods are used to measure precipitation differences around the high rise building. Tipping bucket rain gauges have been placed on two elevator shaft housings on the low rise building, of which one is situated in the shadow of the high rise building. Simultaneously, runoff from the elevator shafts is measured. A comparison of the different methods will be presented.

  12. A method for generating high resolution satellite image time series

    NASA Astrophysics Data System (ADS)

    Guo, Tao

    2014-10-01

    There is an increasing demand for satellite remote sensing data with both high spatial and temporal resolution in many applications. But it still is a challenge to simultaneously improve spatial resolution and temporal frequency due to the technical limits of current satellite observation systems. To this end, much R&D efforts have been ongoing for years and lead to some successes roughly in two aspects, one includes super resolution, pan-sharpen etc. methods which can effectively enhance the spatial resolution and generate good visual effects, but hardly preserve spectral signatures and result in inadequate analytical value, on the other hand, time interpolation is a straight forward method to increase temporal frequency, however it increase little informative contents in fact. In this paper we presented a novel method to simulate high resolution time series data by combing low resolution time series data and a very small number of high resolution data only. Our method starts with a pair of high and low resolution data set, and then a spatial registration is done by introducing LDA model to map high and low resolution pixels correspondingly. Afterwards, temporal change information is captured through a comparison of low resolution time series data, and then projected onto the high resolution data plane and assigned to each high resolution pixel according to the predefined temporal change patterns of each type of ground objects. Finally the simulated high resolution data is generated. A preliminary experiment shows that our method can simulate a high resolution data with a reasonable accuracy. The contribution of our method is to enable timely monitoring of temporal changes through analysis of time sequence of low resolution images only, and usage of costly high resolution data can be reduces as much as possible, and it presents a highly effective way to build up an economically operational monitoring solution for agriculture, forest, land use investigation

  13. A high resolution global scale groundwater model

    NASA Astrophysics Data System (ADS)

    de Graaf, Inge; Sutanudjaja, Edwin; van Beek, Rens; Bierkens, Marc

    2014-05-01

    As the world's largest accessible source of freshwater, groundwater plays a vital role in satisfying the basic needs of human society. It serves as a primary source of drinking water and supplies water for agricultural and industrial activities. During times of drought, groundwater storage provides a large natural buffer against water shortage and sustains flows to rivers and wetlands, supporting ecosystem habitats and biodiversity. Yet, the current generation of global scale hydrological models (GHMs) do not include a groundwater flow component, although it is a crucial part of the hydrological cycle. Thus, a realistic physical representation of the groundwater system that allows for the simulation of groundwater head dynamics and lateral flows is essential for GHMs that increasingly run at finer resolution. In this study we present a global groundwater model with a resolution of 5 arc-minutes (approximately 10 km at the equator) using MODFLOW (McDonald and Harbaugh, 1988). With this global groundwater model we eventually intend to simulate the changes in the groundwater system over time that result from variations in recharge and abstraction. Aquifer schematization and properties of this groundwater model were developed from available global lithological maps and datasets (Dürr et al., 2005; Gleeson et al., 2010; Hartmann and Moosdorf, 2013), combined with our estimate of aquifer thickness for sedimentary basins. We forced the groundwater model with the output from the global hydrological model PCR-GLOBWB (van Beek et al., 2011), specifically the net groundwater recharge and average surface water levels derived from routed channel discharge. For the parameterization, we relied entirely on available global datasets and did not calibrate the model so that it can equally be expanded to data poor environments. Based on our sensitivity analysis, in which we run the model with various hydrogeological parameter settings, we observed that most variance in groundwater

  14. The High Time Resolution Radio Sky

    NASA Astrophysics Data System (ADS)

    Thornton, D.

    2013-11-01

    Pulsars are laboratories for extreme physics unachievable on Earth. As individual sources and possible orbital companions can be used to study magnetospheric, emission, and superfluid physics, general relativistic effects, and stellar and binary evolution. As populations they exhibit a wide range of sub-types, with parameters varying by many orders of magnitude signifying fundamental differences in their evolutionary history and potential uses. There are currently around 2200 known pulsars in the Milky Way, the Magellanic clouds, and globular clusters, most of which have been discovered with radio survey observations. These observations, as well as being suitable for detecting the repeating signals from pulsars, are well suited for identifying other transient astronomical radio bursts that last just a few milliseconds that either singular in nature, or rarely repeating. Prior to the work of this thesis non-repeating radio transients at extragalactic distances had possibly been discovered, however with just one example status a real astronomical sources was in doubt. Finding more of these sources was a vital to proving they were real and to open up the universe for millisecond-duration radio astronomy. The High Time Resolution Universe survey uses the multibeam receiver on the 64-m Parkes radio telescope to search the whole visible sky for pulsars and transients. The temporal and spectral resolution of the receiver and the digital back-end enable the detection of relatively faint, and distant radio sources. From the Parkes telescope a large portion of the Galactic plane can be seen, a rich hunting ground for radio pulsars of all types, while previously poorly surveyed regions away from the Galactic plane are also covered. I have made a number of pulsar discoveries in the survey, including some rare systems. These include PSR J1226-6208, a possible double neutron star system in a remarkably circular orbit, PSR J1431-471 which is being eclipsed by its companion with

  15. High-speed segmentation-driven high-resolution matching

    NASA Astrophysics Data System (ADS)

    Ekstrand, Fredrik; Ahlberg, Carl; Ekström, Mikael; Spampinato, Giacomo

    2015-02-01

    This paper proposes a segmentation-based approach for matching of high-resolution stereo images in real time. The approach employs direct region matching in a raster scan fashion influenced by scanline approaches, but with pixel decoupling. To enable real-time performance it is implemented as a heterogeneous system of an FPGA and a sequential processor. Additionally, the approach is designed for low resource usage in order to qualify as part of unified image processing in an embedded system.

  16. High resolution reservoir geological modelling using outcrop information

    SciTech Connect

    Zhang Changmin; Lin Kexiang; Liu Huaibo

    1997-08-01

    This is China`s first case study of high resolution reservoir geological modelling using outcrop information. The key of the modelling process is to build a prototype model and using the model as a geological knowledge bank. Outcrop information used in geological modelling including seven aspects: (1) Determining the reservoir framework pattern by sedimentary depositional system and facies analysis; (2) Horizontal correlation based on the lower and higher stand duration of the paleo-lake level; (3) Determining the model`s direction based on the paleocurrent statistics; (4) Estimating the sandbody communication by photomosaic and profiles; (6) Estimating reservoir properties distribution within sandbody by lithofacies analysis; and (7) Building the reservoir model in sandbody scale by architectural element analysis and 3-D sampling. A high resolution reservoir geological model of Youshashan oil field has been built by using this method.

  17. High-resolution microwave images of saturn.

    PubMed

    Grossman, A W; Muhleman, D O; Berge, G L

    1989-09-15

    An analysis of high-resolution microwave images of Saturn and Saturn's individual rings is presented. Radio interferometric observations of Saturn taken at the Very Large Array in New Mexico at wavelengths of 2 and 6 centimeters reveal interesting new features in both the atmosphere and rings. The resulting maps show an increase in brightness temperature of about 3 K from equator to pole at both wavelengths, while the 6-centimeter map shows a bright band at northern mid-latitudes. The data are consistent with a radiative transfer model of the atmosphere that constrains the well-mixed, fully saturated, NH(3) mixing ratio to be 1.2 x 10(-4) in a region just below the NH(3) clouds, while the observed bright band indicates a 25 percent relative decrease of NH(3) in northern mid-latitudes. Brightness temperatures for the classical rings are presented. Ring brightness shows a variation with azimuth and is linearly polarized at an average value of about 5 percent. The variations in ring polarization suggest that at least 20 percent of the ring brightness is the result of a single scattering process. PMID:17747882

  18. High resolution EUV monochromator/spectrometer

    DOEpatents

    Koike, Masako

    1996-06-18

    This invention is related to a monochromator which employs a spherical mirror, a traveling plane mirror with simultaneous rotation, and a varied spacing plane grating. The divergent beam from the entrance slit is converged by the spherical mirror located at the various positions in the monochromator depending of the inventive system. To provide the meaningful diffraction efficiencies and to reduce unwanted higher order lights, the deviation angle subtending the incidence and diffraction beams for the plane grating is varied with the position of the traveling plane mirror with simultaneous rotation located in the front or back of the plane grating with wavelength scanning. The outgoing beam from the monochromator goes through the fixed exit slit and has same beam direction regardless of the scanning wavelength. The combination of properly designed motions of the plane mirror and novel varied-spacing parameters of the inventive plane grating corrects the aberrations and focuses the monochromatic spectral image on the exit slit, enabling measurements at high spectral resolution. 10 figs.

  19. High resolution EUV monochromator/spectrometer

    DOEpatents

    Koike, Masako

    1996-01-01

    This invention is related to a monochromator which employs a spherical mirror, a traveling plane mirror with simultaneous rotation, and a varied spacing plane grating. The divergent beam from the entrance slit is converged by the spherical mirror located at the various positions in the monochromator depending of the inventive system. To provide the meaningful diffraction efficiencies and to reduce unwanted higher order lights, the deviation angle subtending the incidence and diffraction beams for the plane grating is varied with the position of the traveling plane mirror with simultaneous rotation located in the front or back of the plane grating with wavelength scanning. The outgoing beam from the monochromator goes through the fixed exit slit and has same beam direction regardless of the scanning wavelength. The combination of properly designed motions of the plane mirror and novel varied-spacing parameters of the inventive plane grating corrects the aberrations and focuses the monochromatic spectral image on the exit slit, enabling measurements at high spectral resolution.

  20. High resolution gas volume change sensor

    SciTech Connect

    Dirckx, Joris J. J.; Aernouts, Jef E. F.; Aerts, Johan R. M.

    2007-05-15

    Changes of gas quantity in a system can be measured either by measuring pressure changes or by measuring volume changes. As sensitive pressure sensors are readily available, pressure change is the commonly used technique. In many physiologic systems, however, buildup of pressure influences the gas exchange mechanisms, thus changing the gas quantity change rate. If one wants to study the gas flow in or out of a biological gas pocket, measurements need to be done at constant pressure. In this article we present a highly sensitive sensor for quantitative measurements of gas volume change at constant pressure. The sensor is based on optical detection of the movement of a droplet of fluid enclosed in a capillary. The device is easy to use and delivers gas volume data at a rate of more than 15 measurements/s and a resolution better than 0.06 {mu}l. At the onset of a gas quantity change the sensor shows a small pressure artifact of less than 15 Pa, and at constant change rates the pressure artifact is smaller than 10 Pa or 0.01% of ambient pressure.

  1. Europa Ice Cliffs-High Resolution

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This view of the Conamara Chaos region on Jupiter's moon Europa shows cliffs along the edges of high-standing ice plates. The washboard texture of the older terrain has been broken into plates which are separated by material with a jumbled texture. The cliffs themselves are rough and broadly scalloped, and smooth debris shed from the cliff faces is piled along the base. For scale, the height of the cliffs and size of the scalloped indentations are comparable to the famous cliff face of Mount Rushmore in South Dakota.

    This image was taken on December 16, 1997 at a range of 900 kilometers (540 miles) by the solid state imaging system (camera) on NASA's Galileo spacecraft. North is to the top right of the picture, and the sun illuminates the surface from the east. This image, centered at approximately 8 degrees north latitude and 273 degrees west longitude, covers an area approximately 1.5 kilometers by 4 kilometers (0.9 miles by 2.4 miles). The resolution is 9 meters (30 feet) per picture element.

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).

    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://www.jpl.nasa.gov/ galileo.

  2. High vertical resolution crosswell seismic imaging

    DOEpatents

    Lazaratos, Spyridon K.

    1999-12-07

    A method for producing high vertical resolution seismic images from crosswell data is disclosed. In accordance with one aspect of the disclosure, a set of vertically spaced, generally horizontally extending continuous layers and associated nodes are defined within a region between two boreholes. The specific number of nodes is selected such that the value of a particular characteristic of the subterranean region at each of the nodes is one which can be determined from the seismic data. Once values are established at the nodes, values of the particular characteristic are assigned to positions between the node points of each layer based on the values at node within that layer and without regard to the values at node points within any other layer. A seismic map is produced using the node values and the assigned values therebetween. In accordance with another aspect of the disclosure, an approximate model of the region is established using direct arrival traveltime data. Thereafter, the approximate model is adjusted using reflected arrival data. In accordance with still another aspect of the disclosure, correction is provided for well deviation. An associated technique which provides improvements in ray tracing is also disclosed.

  3. The High Resolution Tropospheric Ozone Residual

    NASA Technical Reports Server (NTRS)

    Schoeberl, Mark R.

    2006-01-01

    The co-flight of the MLS stratospheric limb sounder and the Ozone Monitoring Instrument (OMI) provides the capability of computing the Tropospheric Ozone Residual (TOR) in much greater detail [Ziemke et al., 2006]. Using forward trajectory calculations of MLS ozone measurements combined with OMI column ozone we have developed a high horizontal resolution tropospheric ozone residual (HTOR) which can provide even more detail than the standard TOR product. HTOR is especially useful for extra-tropical studies of tropospheric ozone transport. We find that both the Pacific pollution corridor (East Asia to Alaska) and the Atlantic pollution corridor (North America east coast to Europe) are also preferred locations for strat-trop folds leading to systematic overestimates of pollution amounts. In fact, fold events appear to dominate extra-tropical Northern Hemisphere day-to-day maps of HTOR. Model estimates of the tropospheric column are in reasonable agreement with the HTOR amounts when offsets due to different tropopause height calculations are taken into consideration.

  4. High-Resolution and Animal Imaging Instrumentation and Techniques

    NASA Astrophysics Data System (ADS)

    Belcari, Nicola; Guerra, AlbertoDel

    During the last decade we have observed a growing interest in "in vivo" imaging techniques for small animals. This is due to the necessity of studying biochemical processes at a molecular level for pharmacology, genetic, and pathology investigations. This field of research is usually called "molecular imaging."Advances in biological understanding have been accompanied by technological advances in instrumentation and techniques and image-reconstruction software, resulting in improved image quality, visibility, and interpretation. The main technological challenge is then the design of systems with high spatial resolution and high sensitivity.

  5. High-level-waste immobilization

    SciTech Connect

    Crandall, J L

    1982-01-01

    Analysis of risks, environmental effects, process feasibility, and costs for disposal of immobilized high-level wastes in geologic repositories indicates that the disposal system safety has a low sensitivity to the choice of the waste disposal form.

  6. Modelling coastal low-level wind-jets: does horizontal resolution matter?

    NASA Astrophysics Data System (ADS)

    Ranjha, Raza; Tjernström, Michael; Svensson, Gunilla; Semedo, Alvaro

    2016-04-01

    Atmospheric flows in coastal regions are impacted by land-sea temperature contrasts, complex terrain, shape of the coastline, among many things. Along the west coast of central North America, winds in the boundary layer are mainly from north or northwest, roughly parallel to the coastline. Frequently, the coastal low-level wind field is characterized by a sharp wind maximum along the coast in the lowest kilometre. This feature, commonly referred to as a coastal low-level jet (CLLJ), has significant impact on the climatology of the coastal region and affects many human activities in the littoral zone. Hence, a good understanding and forecasting of CLLJs are vital. This study evaluates the issue of proper mesoscale numerical model resolution to describe the physics of a CLLJ, and its impact on the upper ocean. The COAMPS® model is used for a summer event to determine the realism of the model results compared to observations, from an area of supercritical flow adjustment between Pt. Sur and Pt. Conception, California. Simulations at different model horizontal resolutions, from 54 to 2 km are performed. While the model produces realistic results with increasing details at higher resolution, the results do not fully converge even at a resolution of only few kilometres and an objective analysis of model errors do not show an increased skill with increasing resolution. Based on all available information, a compromise resolution appears to be at least 6 km. New methods may have to be developed to evaluate models at very high resolution.

  7. High-resolution ophthalmic imaging system

    DOEpatents

    Olivier, Scot S.; Carrano, Carmen J.

    2007-12-04

    A system for providing an improved resolution retina image comprising an imaging camera for capturing a retina image and a computer system operatively connected to the imaging camera, the computer producing short exposures of the retina image and providing speckle processing of the short exposures to provide the improved resolution retina image. The system comprises the steps of capturing a retina image, producing short exposures of the retina image, and speckle processing the short exposures of the retina image to provide the improved resolution retina image.

  8. High Resolution X-Ray Explorer (HIREX)

    NASA Technical Reports Server (NTRS)

    Golub, Leon

    1999-01-01

    SAO has carried out a study to determine the feasibility of building an orbiting telescope capable of resolving 7 km structure on the Sun. In order to achieve the required imaging the telescope must have a resolution 0.01 arcsec. This fact challenges the state of the art of orbiting telescopes in several areas: mirror figuring; optical metrology; optical mounting; mirror figure control; system alignment; optical stability; observatory pointing; and image stability image stability. The telescope design concept is based on a 0.6m Cassegrain-style telescope with a 240 meter effective focal length. This is achieved with 2 mirrors supported at opposite ends of a 27 m space-deployable boom. The telescope mirrors are coated with multilayers designed to reflect a broad XUV passband. A third, small mirror, near the focal plane performs the function of selecting the narrow band that is finally imaged. Image stabilization to the 0.005 a,rcsec level is achieved by active control of the secondary mirror. The primary mirror is held unadjustably to the spacecraft, its pointing set by the space- craft orientation. The secondary mirror is mounted on a 6-axis stage that permits its position to be changed to align the telescope in space. The stage is intended for intermittent adjustment, both because of its speed of travel, and the TBD alignment procedure. The third mirror is called the TXI (Tuneable X-ray Imager). It is mounted on a gimbal that permits it to be tipped over a 60 degree range, selecting between the individual wavelengths in the initial bandpass. It can also rotated completely out of the way to allow the full, broadband EUV flux to strike the focal plane.

  9. Synthetic vision helicopter flights using high resolution LIDAR terrain data

    NASA Astrophysics Data System (ADS)

    Sindlinger, A.; Meuter, M.; Barraci, N.; Güttler, M.; Klingauf, U.; Schiefele, J.; Howland, D.

    2006-05-01

    Helicopters are widely used for operations close to terrain such as rescue missions; therefore all-weather capabilities are highly desired. To minimize or even avoid the risk of collision with terrain and obstacles, Synthetic Vision Systems (SVS) could be used to increase situational awareness. In order to demonstrate this, helicopter flights have been performed in the area of Zurich, Switzerland A major component of an SVS is the three-dimensional (3D) depiction of terrain data, usually presented on the primary flight display (PFD). The degree of usability in low level flight applications is a function of the terrain data quality. Today's most precise, large scale terrain data are derived from airborne laser scanning technologies such as LIDAR (light detection and ranging). A LIDAR dataset provided by Swissphoto AG, Zurich with a resolution of 1m was used. The depiction of high resolution terrain data consisting of 1 million elevation posts per square kilometer on a laptop in an appropriate area around the helicopter is challenging. To facilitate the depiction of the high resolution terrain data, it was triangulated applying a 1.5m error margin making it possible to depict an area of 5x5 square kilometer around the helicopter. To position the camera correctly in the virtual scene the SVS had to be supplied with accurate navigation data. Highly flexible and portable measurement equipment which easily could be used in most aircrafts was designed. Demonstration flights were successfully executed in September, October 2005 in the Swiss Alps departing from Zurich.

  10. Large Scale, High Resolution, Mantle Dynamics Modeling

    NASA Astrophysics Data System (ADS)

    Geenen, T.; Berg, A. V.; Spakman, W.

    2007-12-01

    To model the geodynamic evolution of plate convergence, subduction and collision and to allow for a connection to various types of observational data, geophysical, geodetical and geological, we developed a 4D (space-time) numerical mantle convection code. The model is based on a spherical 3D Eulerian fem model, with quadratic elements, on top of which we constructed a 3D Lagrangian particle in cell(PIC) method. We use the PIC method to transport material properties and to incorporate a viscoelastic rheology. Since capturing small scale processes associated with localization phenomena require a high resolution, we spend a considerable effort on implementing solvers suitable to solve for models with over 100 million degrees of freedom. We implemented Additive Schwartz type ILU based methods in combination with a Krylov solver, GMRES. However we found that for problems with over 500 thousend degrees of freedom the convergence of the solver degraded severely. This observation is known from the literature [Saad, 2003] and results from the local character of the ILU preconditioner resulting in a poor approximation of the inverse of A for large A. The size of A for which ILU is no longer usable depends on the condition of A and on the amount of fill in allowed for the ILU preconditioner. We found that for our problems with over 5×105 degrees of freedom convergence became to slow to solve the system within an acceptable amount of walltime, one minute, even when allowing for considerable amount of fill in. We also implemented MUMPS and found good scaling results for problems up to 107 degrees of freedom for up to 32 CPU¡¯s. For problems with over 100 million degrees of freedom we implemented Algebraic Multigrid type methods (AMG) from the ML library [Sala, 2006]. Since multigrid methods are most effective for single parameter problems, we rebuild our model to use the SIMPLE method in the Stokes solver [Patankar, 1980]. We present scaling results from these solvers for 3D

  11. Single sensor processing to obtain high resolution color component signals

    NASA Technical Reports Server (NTRS)

    Glenn, William E. (Inventor)

    2010-01-01

    A method for generating color video signals representative of color images of a scene includes the following steps: focusing light from the scene on an electronic image sensor via a filter having a tri-color filter pattern; producing, from outputs of the sensor, first and second relatively low resolution luminance signals; producing, from outputs of the sensor, a relatively high resolution luminance signal; producing, from a ratio of the relatively high resolution luminance signal to the first relatively low resolution luminance signal, a high band luminance component signal; producing, from outputs of the sensor, relatively low resolution color component signals; and combining each of the relatively low resolution color component signals with the high band luminance component signal to obtain relatively high resolution color component signals.

  12. The NASA High Resolution Microwave Survey

    NASA Astrophysics Data System (ADS)

    Tarter, J. C.; Gulkis, S.

    1993-05-01

    The NASA High Resolution Microwave Survey (HRMS) began a decade of planned observations to search for signals of extraterrestrial intelligent origin with inaugural ceremonies at two sites on October 12, 1992. At Goldstone, California the Sky Survey began executing precisely controlled scanning patterns on the celestial sphere using a new beam waveguide 34m antenna operating at a frequency near 8500 MHz (X-band). At Arecibo, Puerto Rico the Targeted Search began tracking GL615.1A, one of 24 solar-type stars selected for these inaugural observations, using the NAIC 300m radio telescope operating in a band of frequencies centered at 1406 MHz. Since the initiation of the search, the Sky Survey has completed X-band observations of several dozen sky-frames measuring 30(deg) times 1.5(deg) . In addition, observations of selected areas of the galactic plane have been observed in several frequency bands (1400 MHz and 1600 MHz) using a 26m antenna located near the 34m antenna. The Targeted Search has completed the first 200 hours of observations at Arecibo covering some 300 MHz of bandwidth. This paper summarizes the results of the observations to date, including a synopsis of the interference observed at the Goldstone and Arecibo sites, and a discussion of techniques that will be used to improve future observations. The HRMS program is managed by the Ames Research Center in collaboration with the Jet Propulsion Laboratory. The results presented in this paper represent the efforts of a team of scientists and engineers at these two institutions as well as the SETI Institute, Silicon Engines Inc., John C. Reykjalin Inc., Sverdrup Technology, Sterling Federal Systems, Cornell University, the Harvard-Smithsonian Center for Astrophysics, the American Astronomical Society, Arecibo Observatory, UC Santa Cruz, the University of Washington, UC Berkeley, California Institute of Technology, Georgia Institute of Technology, Innovative Systems, and the Space Telescope Science Institute.

  13. MULTIPULSE - high resolution and high power in one TDEM system

    NASA Astrophysics Data System (ADS)

    Chen, Tianyou; Hodges, Greg; Miles, Philip

    2015-09-01

    An airborne time domain electromagnetic (TEM) system with high resolution and great depth of exploration is desired for geological mapping as well as for mineral exploration. The MULTIPULSE technology enables an airborne TEM system to transmit a high power pulse (a half-sine, for instance) and one or multiple low power pulse(s) (trapezoid or square) within a half-cycle. The high power pulse ensures good depth of exploration and the low power pulse allows a fast transmitter current turn off and earlier off-time measurement thus providing higher frequency signals, which allows higher near-surface resolution and better sensitivity to weak conductors. The power spectrum of the MULTIPULSE waveform comprising a half-sine and a trapezoid pulse clearly shows increased power in the higher frequency range (> ~2.3 kHz) compared to that of a single half-sine waveform. The addition of the low power trapezoid pulse extends the range of the sensitivity 10-fold towards the weak conductors, expanding the geological conductivity range of a system and increasing the scope of its applications. The MULTIPULSE technology can be applied to standard single-pulse airborne TEM systems on both helicopter and fixed-wing. We field tested the HELITEM MULTIPULSE system over a wire-loop in Iroquois Falls, demonstrating the different sensitivity of the high and low power pulses to the overburden and the wire-loop. We also tested both HELITEM and GEOTEM MULTIPULSE systems over a layered oil sand geologic setting in Fort McMurray, Alberta, Canada. The results show comparable shallow geologic resolution of the MULTIPULSE to that of the RESOLVE system while maintaining superior depth of exploration, confirming the increased geological conductivity range of a system employing MULTIPULSE compared to the standard single-pulse systems.

  14. Regional High Resolution Reanalysis Covered European North East Shelf

    NASA Astrophysics Data System (ADS)

    Bourdalle-Badie, R.; Benkiran, M.; Chanut, J.; Drillet, Y.; Reffray, G.

    2011-12-01

    Mercator-Ocean has developed a regional forecasting system at 1/12° resolution over the North East Atlantic (IBI: Iberia, Biscay and Irish), taking advantage of the recent developments in NEMO. This regional forecasting system uses boundary conditions from the Mercator-Ocean global reanalysis (GLORYS: Global Ocean ReanalYses and Simulations). The assimilation component of the Mercator Ocean system, is based on a reduced-order Kalman filter (the SEEK or Singular Extended Evolutive Kalman filter). An IAU method (Incremental Analysis Updates) is used to apply the increments in the system. The error statistics are represented in a sub-space spanned by a small number of dominant 3D error directions. The data assimilation system allows to constrain the model in a multivariate way with Sea Surface Temperature (AVHRR + Multi-satellite High resolution), together with all available satellite Sea Level Anomalies, and with in situ observations from the CORA-03 data base, including ARGO floats temperature and salinity measurements. This reanalysis covers the period from January 2002 to December 2009. In this presentation, the results obtained with this reanalysis system (1/12°) are compared to the GLORYS ones. A special focus will be made on the gain thanks to the higher resolution of the model and higher resolution of the SST assimilated in this reanalysis.

  15. A comparison study of tropical Pacific ocean state estimation: Low-resolution assimilation vs. high-resolution simulation.

    NASA Astrophysics Data System (ADS)

    Fu, Weiwei; Zhu, Jiang; Zhou, Guangqing; Wang, Huijun

    2005-03-01

    A comparison study is performed to contrast the improvements in the tropical Pacific oceanic state of a low-resolution model respectively via data assimilation and by an increase in horizontal resolution. A low resolution model (LR) (1°lat by 2°lon) and a high-resolution model (HR) (0.5°lat by 0.5°lon) are employed for the comparison. The authors perform 20-yr numerical experiments and analyze the annual mean fields of temperature and salinity. The results indicate that the low-resolution model with data assimilation behaves better than the high-resolution model in the estimation of ocean large-scale features. From 1990 to 2000, the average of HR’s RMSE (root-mean-square error) relative to independent Tropical Atmosphere Ocean project (TAO) mooring data at randomly selected points is 0.97°C compared to a RMSE of 0.56°C for LR with temperature assimilation. Moreover, the LR with data assimilation is more frugal in computation. Although there is room to improve the high-resolution model, the low-resolution model with data assimilation may be an advisable choice in achieving a more realistic large-scale state of the ocean at the limited level of information provided by the current observational system.

  16. High Resolution Sensor for Nuclear Waste Characterization

    SciTech Connect

    Shah, Kanai; Higgins, William; Van Loef, Edgar V

    2006-01-23

    Gamma ray spectrometers are an important tool in the characterization of radioactive waste. Important requirements for gamma ray spectrometers used in this application include good energy resolution, high detection efficiency, compact size, light weight, portability, and low power requirements. None of the available spectrometers satisfy all of these requirements. The goal of the Phase I research was to investigate lanthanum halide and related scintillators for nuclear waste clean-up. LaBr3:Ce remains a very promising scintillator with high light yield and fast response. CeBr3 is attractive because it is very similar to LaBr3:Ce in terms of scintillation properties and also has the advantage of much lower self-radioactivity, which may be important in some applications. CeBr3 also shows slightly higher light yield at higher temperatures than LaBr3 and may be easier to produce with high uniformity in large volume since it does not require any dopants. Among the mixed lanthanum halides, the light yield of LaBrxI3-x:Ce is lower and the difference in crystal structure of the binaries (LaBr3 and LaI3) makes it difficult to grow high quality crystals of the ternary as the iodine concentration is increased. On the other hand, LaBrxCl3-x:Ce provides excellent performance. Its light output is high and it provides fast response. The crystal structures of the two binaries (LaBr3 and LaCl3) are very similar. Overall, its scintillation properties are very similar to those for LaBr3:Ce. While the gamma-ray stopping efficiency of LaBrxCl3-x:Ce is lower than that for LaBr3:Ce (primarily because the density of LaCl3 is lower than that of LaBr3), it may be easier to grow large crystals of LaBrxCl3-x:Ce than LaBr3:Ce since in some instances (for example, CdxZn1-xTe), the ternary compounds provide increased flexibility in the crystal lattice. Among the new dopants, Eu2+ and Pr3+, tried in LaBr3 host crystals, the Eu2+ doped samples exhibited low light output. This was mostly because a

  17. Multimodal microscopy with high resolution spectral focusing CARS

    NASA Astrophysics Data System (ADS)

    Baldacchini, Tommaso; Zadoyan, Ruben

    2014-02-01

    In this work we describe a device that extends capabilities of multiphoton microscopes based on dual wavelength output femtosecond laser sources. CARS with 17cm-1 spectral resolution is experimentally demonstrated. Our approach is based on spectral focusing CARS. For pulse shaping of the pump and Stokes beams we utilize transmission gratings based stretcher. It allows the dispersion of the stretcher to be continuously adjusted in wide range. The best spectral resolution is achieved when the chirp rates in both pump and Stokes beam are matched. The device is automated. Any change in the beam path lengths due to the stretcher adjustment or wavelength tuning is compensated by the delay line. We incorporated into the device a computer controlled beam pointing stabilization system that compensates the beam pointing deviation due to dispersion in the system. High level of automation and computer control makes the operation of the device easy. We present CARS images of several samples that demonstrate high spectral resolution, high contrast and chemical selectivity.

  18. High resolution ultrasound and photoacoustic imaging of single cells

    PubMed Central

    Strohm, Eric M.; Moore, Michael J.; Kolios, Michael C.

    2016-01-01

    High resolution ultrasound and photoacoustic images of stained neutrophils, lymphocytes and monocytes from a blood smear were acquired using a combined acoustic/photoacoustic microscope. Photoacoustic images were created using a pulsed 532 nm laser that was coupled to a single mode fiber to produce output wavelengths from 532 nm to 620 nm via stimulated Raman scattering. The excitation wavelength was selected using optical filters and focused onto the sample using a 20× objective. A 1000 MHz transducer was co-aligned with the laser spot and used for ultrasound and photoacoustic images, enabling micrometer resolution with both modalities. The different cell types could be easily identified due to variations in contrast within the acoustic and photoacoustic images. This technique provides a new way of probing leukocyte structure with potential applications towards detecting cellular abnormalities and diseased cells at the single cell level. PMID:27114911

  19. High resolution spectroscopic study of Be10Lambda;

    NASA Astrophysics Data System (ADS)

    Gogami, T.; Chen, C.; Kawama, D.; Achenbach, P.; Ahmidouch, A.; Albayrak, I.; Androic, D.; Asaturyan, A.; Asaturyan, R.; Ates, O.; Baturin, P.; Badui, R.; Boeglin, W.; Bono, J.; Brash, E.; Carter, P.; Chiba, A.; Christy, E.; Danagoulian, S.; de Leo, R.; Doi, D.; Elaasar, M.; Ent, R.; Fujii, Y.; Fujita, M.; Furic, M.; Gabrielyan, M.; Gan, L.; Garibaldi, F.; Gaskell, D.; Gasparian, A.; Han, Y.; Hashimoto, O.; Horn, T.; Hu, B.; Hungerford, Ed. V.; Jones, M.; Kanda, H.; Kaneta, M.; Kato, S.; Kawai, M.; Khanal, H.; Kohl, M.; Liyanage, A.; Luo, W.; Maeda, K.; Margaryan, A.; Markowitz, P.; Maruta, T.; Matsumura, A.; Maxwell, V.; Mkrtchyan, A.; Mkrtchyan, H.; Nagao, S.; Nakamura, S. N.; Narayan, A.; Neville, C.; Niculescu, G.; Niculescu, M. I.; Nunez, A.; Nuruzzaman, Okayasu, Y.; Petkovic, T.; Pochodzalla, J.; Qiu, X.; Reinhold, J.; Rodriguez, V. M.; Samanta, C.; Sawatzky, B.; Seva, T.; Shichijo, A.; Tadevosyan, V.; Tang, L.; Taniya, N.; Tsukada, K.; Veilleux, M.; Vulcan, W.; Wesselmann, F. R.; Wood, S. A.; Yamamoto, T.; Ya, L.; Ye, Z.; Yokota, K.; Yuan, L.; Zhamkochyan, S.; Zhu, L.; Hksjlab E05-115 Collaboration

    2016-03-01

    Spectroscopy of a Be10Lambda; hypernucleus was carried out at JLab Hall C using the (e ,e'K+) reaction. A new magnetic spectrometer system (SPL+HES+HKS), specifically designed for high resolution hypernuclear spectroscopy, was used to obtain an energy spectrum with a resolution of ˜0.78 MeV (FWHM). The well-calibrated spectrometer system of the present experiment using p (e ,e'K+)Λ ,Σ0 reactions allowed us to determine the energy levels; and the binding energy of the ground-state peak (mixture of 1- and 2- states) was found to be BΛ=8.55 ±0.07 (stat . ) ±0.11 (sys . ) MeV. The result indicates that the ground-state energy is shallower than that of an emulsion study by about 0.5 MeV which provides valuable experimental information on the charge symmetry breaking effect in the Λ N interaction.

  20. High-resolution infrared studies of the ʋ10, ʋ11, ʋ14, and ʋ18 levels of [1.1.1]propellane

    SciTech Connect

    Kirkpatrick, Robynne W.; Masiello, Tony; Martin, Matthew A.; Nibler, Joseph W.; Maki, Arthur; Weber, Alfons; Blake, Thomas A.

    2012-11-15

    This paper is a continuation of earlier work for which the high resolution infrared spectrum of [1.1.1]propellane was measured and its k and l structure resolved for the first time. Here we present results from an analysis of more than 16,000 transitions involving three fundamental bands ʋ10 (E′-A1'), ʋ11 (E′-A1'), ʋ14 (A2″-A1') and two difference bands (ʋ10- ʋ18) (E'-E″) and (ʋ1118) (E'-E"). Additional information about ʋ18 was also obtained from the difference band (ʋ1518)-ʋ18 (E'-E") and the binary combination band (ʋ1518) (E'-A1'). Through the use of the ground state constants reported in an earlier paper [1], rovibrational constants have been determined for all the vibrational states involved in these bands. The rovibrational parameters for the ʋ18(E″) state were obtained from combination-differences and showed no need to include interactions with other states. The ʋ10(E′) state analysis was also straight-forward, with only a weak Coriolis interaction with the levels of the ʋ14(A2″) state. The latter levels are much more affected by a strong Coriolis interaction with the levels of the nearby ʋ11(E′) state and also by a small but significant interaction with another state, presumably the ʋ16(E″) state, that is not directly observed. Gaussian calculations (B3LYP/cc-pVTZ) computed at the anharmonic level aided the analyses by providing initial values for many of the parameters. These theoretical results generally compare favorably with the final parameter values deduced from the spectral analyses. Finally, evidence was obtained for several level crossings between the rotational levels of the ʋ11 and ʋ14 states and, using a weak coupling term corresponding to a Δk = ±5, Δl = ∓1 matrix element, it was possible to find

  1. Estimation of reactogenicity of preparations produced on the basis of photoinactivated live vaccines against brucellosis and tularaemia on the organismic level. 2. Using the method of speckle-microscopy with high spatial resolution

    SciTech Connect

    Ulianova, O V; Uianov, S S; Li Pengcheng; Luo Qingming

    2011-04-30

    The method of speckle microscopy was adapted to estimate the reactogenicity of the prototypes of vaccine preparations against extremely dangerous infections. The theory is proposed to describe the mechanism of formation of the output signal from the super-high spatial resolution speckle microscope. The experimental studies show that bacterial suspensions, irradiated in different regimes of inactivation, do not exert negative influence on the blood microcirculations in laboratory animals. (optical technologies in biophysics and medicine)

  2. Estimation of reactogenicity of preparations produced on the basis of photoinactivated live vaccines against brucellosis and tularaemia on the organismic level.2. Using the method of speckle-microscopy with high spatial resolution

    NASA Astrophysics Data System (ADS)

    Ulianova, O. V.; Uianov, S. S.; Li, Pengcheng; Luo, Qingming

    2011-04-01

    The method of speckle microscopy was adapted to estimate the reactogenicity of the prototypes of vaccine preparations against extremely dangerous infections. The theory is proposed to describe the mechanism of formation of the output signal from the super-high spatial resolution speckle microscope. The experimental studies show that bacterial suspensions, irradiated in different regimes of inactivation, do not exert negative influence on the blood microcirculations in laboratory animals.

  3. High resolution non-iterative aperture synthesis.

    PubMed

    Kraczek, Jeffrey R; McManamon, Paul F; Watson, Edward A

    2016-03-21

    The maximum resolution of a multiple-input multiple-output (MIMO) imaging system is determined by the size of the synthetic aperture. The synthetic aperture is determined by a coordinate shift using the relative positions of the illuminators and receive apertures. Previous methods have shown non-iterative phasing for multiple illuminators with a single receive aperture for intra-aperture synthesis. This work shows non-iterative phasing with both multiple illuminators and multiple receive apertures for inter-aperture synthesis. Simulated results show that piston, tip, and tilt can be calculated using inter-aperture phasing after intra-aperture phasing has been performed. Use of a fourth illuminator for increased resolution is shown. The modulation transfer function (MTF) is used to quantitatively judge increased resolution. PMID:27136816

  4. High Spatial Resolution Commercial Satellite Imaging Product Characterization

    NASA Technical Reports Server (NTRS)

    Ryan, Robert E.; Pagnutti, Mary; Blonski, Slawomir; Ross, Kenton W.; Stnaley, Thomas

    2005-01-01

    NASA Stennis Space Center's Remote Sensing group has been characterizing privately owned high spatial resolution multispectral imaging systems, such as IKONOS, QuickBird, and OrbView-3. Natural and man made targets were used for spatial resolution, radiometric, and geopositional characterizations. Higher spatial resolution also presents significant adjacency effects for accurate reliable radiometry.

  5. High spatial resolution restoration of IRAS images

    NASA Technical Reports Server (NTRS)

    Grasdalen, Gary L.; Inguva, R.; Dyck, H. Melvin; Canterna, R.; Hackwell, John A.

    1990-01-01

    A general technique to improve the spatial resolution of the IRAS AO data was developed at The Aerospace Corporation using the Maximum Entropy algorithm of Skilling and Gull. The technique has been applied to a variety of fields and several individual AO MACROS. With this general technique, resolutions of 15 arcsec were achieved in 12 and 25 micron images and 30 arcsec in 60 and 100 micron images. Results on galactic plane fields show that both photometric and positional accuracy achieved in the general IRAS survey are also achieved in the reconstructed images.

  6. High pressure liquid level monitor

    DOEpatents

    Bean, Vern E.; Long, Frederick G.

    1984-01-01

    A liquid level monitor for tracking the level of a coal slurry in a high-pressure vessel including a toroidal-shaped float with magnetically permeable bands thereon disposed within the vessel, two pairs of magnetic field generators and detectors disposed outside the vessel adjacent the top and bottom thereof and magnetically coupled to the magnetically permeable bands on the float, and signal processing circuitry for combining signals from the top and bottom detectors for generating a monotonically increasing analog control signal which is a function of liquid level. The control signal may be utilized to operate high-pressure control valves associated with processes in which the high-pressure vessel is used.

  7. Feature tracking in high-resolution regional climate data

    NASA Astrophysics Data System (ADS)

    Massey, Neil R.

    2016-08-01

    In this paper, a suite of algorithms are presented which facilitate the identification and tracking of storm-indicative features, such as mean sea-level pressure minima, in high resolution regional climate data. The methods employ a hierarchical triangular mesh, which is tailored to the regional climate data by only subdividing triangles, from an initial icosahedron, within the domain of the data. The regional data is then regridded to this triangular mesh at each level of the grid, producing a compact representation of the data at numerous resolutions. Storm indicative features are detected by first subtracting the background field, represented by a low resolution version of the data, which occurs at a lower level in the mesh. Anomalies from this background field are detected, as feature objects, at a mesh level which corresponds to the spatial scale of the feature being detected and then refined to the highest mesh level. These feature objects are expanded to an outer contour and overlapping objects are merged. The centre points of these objects are tracked across timesteps by applying an optimisation scheme which uses five hierarchical rules. Objects are added to tracks based on the highest rule in the scheme they pass and, if two objects pass the same rule, the cost of adding the object to the track. An object exchange scheme ensures that adding an object to a track is locally optimal. An additional track optimisation phase is performed which exchanges segments between tracks and merges tracks to obtain a globally optimal track set. To validate the suite of algorithms they are applied to the ERA-Interim reanalysis dataset and compared to other storm-indicative feature tracking algorithms.

  8. High Resolution Velocity Structure in Eastern Turkey

    NASA Astrophysics Data System (ADS)

    Pasyanos, M. E.; Gok, R.; Zor, E.; Walter, W. R.

    2004-12-01

    We investigate the crust and upper mantle structure of eastern Turkey where the Anatolian, Arabian and Eurasian Plates meet, forming a complex tectonic regime. The Bitlis suture is a continental collision zone between the Anatolian plateau and the Arabian plate. Broadband data available through the Eastern Turkey Seismic Experiment (ETSE) provide a unique opportunity for studying the high resolution velocity structure of the region. Zor et al. (2003) found an average 46 km thick crust in the Anatolian plateau using a six-layered grid search inversion of the ETSE receiver functions. Receiver functions are sensitive to the velocity contrast of interfaces and the relative travel time of converted and reverberated waves between those interfaces. The interpretation of receiver functions alone, however, may result in an apparent depth-velocity trade-off [Ammon et al., 1990]. In order to improve upon this velocity model, we have combined the receiver functions with surface wave data using the joint inversion method of Julia et al. (2000). In this technique, the two sets of observations are combined into a single algebraic equation and each data set is weighted by an estimate of the uncertainty in the observations. The receiver functions are calculated using an iterative time-domain deconvolution technique. We also consider azimuthal changes in the receiver functions and have stacked them into different groups accordingly. We are improving our surface wave model by making Love and Rayleigh dispersion measurements at the ETSE stations and incorporating them into a regional group velocity model for periods between 10 and 100 seconds. Preliminary results indicate a strong trend in the long period group velocities toward the northeast, indicating slow upper mantle velocities in the area consistent with Pn, Sn and receiver function results. Starting models used for the joint inversions include both a 1-D model from a 12-ton dam shot recorded by ETSE [Gurbuz et al., 2004] and

  9. High Resolution Velocity Structure in Eastern Turkey

    SciTech Connect

    Pasyanos, M; Gok, R; Zor, E; Walter, W

    2004-09-03

    We investigate the crustal and upper mantle structure of eastern Turkey where the Anatolian, Arabian and Eurasian Plates meet and form a complex tectonic structure. The Bitlis suture is a continental collision zone between the Anatolian plateau and the Arabian plate. Broadband data available through the Eastern Turkey Seismic Experiment (ETSE) provided a unique opportunity for studying the high resolution velocity structure. Zor et al. found an average 46 km thick crust in Anatolian plateau using six-layered grid search inversion of the ETSE receiver functions. Receiver functions are sensitive to the velocity contrast of interfaces and the relative travel time of converted and reverberated waves between those interfaces. The interpretation of receiver function alone with many-layered parameterization may result in an apparent depth-velocity tradeoff. In order to improve previous velocity model, we employed the joint inversion method with many layered parameterization of Julia et al. (2000) to the ETSE receiver functions. In this technique, the receiver function and surface-wave observations are combined into a single algebraic equation and each data set is weighted by an estimate of the uncertainty in the observations. We consider azimuthal changes of receiver functions and have stacked them into different groups. We calculated the receiver functions using iterative time-domain deconvolution technique and surface wave group velocity dispersion curves between 10-100 sec. We are making surface wave dispersion measurements at the ETSE stations and have incorporated them into a regional group velocity model. Preliminary results indicate a strong trend in the long period group velocity in the northeast. This indicates slow upper mantle velocities in the region consistent with Pn, Sn and receiver function results. We started with both the 1-D model that is obtained with the 12 tones dam explosion shot data recorded by ETSE network and the existing receiver function

  10. High resolution bragg focusing optics for synchrotron monochromators and analyzers

    SciTech Connect

    Knapp, G.S.; Beno, M.A.; Gofron, K.J.

    1997-07-01

    A number of different applications for high resolution Bragg Focusing Optics are reviewed. Applications include Sagittal Focusing, Energy Dispersive optics for x-ray absorption and diffraction, a curved analyzer-multichannel detector method for efficient acquisition of powder and small angle scattering data, the use of Backscattering Analyzers for very high resolution inelastic scattering, and curved crystals for high energy applications.

  11. Beam size measurement at high radiation levels

    SciTech Connect

    Decker, F.J.

    1991-05-01

    At the end of the Stanford Linear Accelerator the high energy electron and positron beams are quite small. Beam sizes below 100 {mu}m ({sigma}) as well as the transverse distribution, especially tails, have to be determined. Fluorescent screens observed by TV cameras provide a quick two-dimensional picture, which can be analyzed by digitization. For running the SLAC Linear Collider (SLC) with low backgrounds at the interaction point, collimators are installed at the end of the linac. This causes a high radiation level so that the nearby cameras die within two weeks and so-called radiation hard'' cameras within two months. Therefore an optical system has been built, which guides a 5 mm wide picture with a resolution of about 30 {mu}m over a distance of 12 m to an accessible region. The overall resolution is limited by the screen thickness, optical diffraction and the line resolution of the camera. Vibration, chromatic effects or air fluctuations play a much less important role. The pictures are colored to get fast information about the beam current, size and tails. Beside the emittance, more information about the tail size and betatron phase is obtained by using four screens. This will help to develop tail compensation schemes to decrease the emittance growth in the linac at high currents. 4 refs., 2 figs.

  12. High-Level Radioactive Waste.

    ERIC Educational Resources Information Center

    Hayden, Howard C.

    1995-01-01

    Presents a method to calculate the amount of high-level radioactive waste by taking into consideration the following factors: the fission process that yields the waste, identification of the waste, the energy required to run a 1-GWe plant for one year, and the uranium mass required to produce that energy. Briefly discusses waste disposal and…

  13. The CMS high level trigger

    NASA Astrophysics Data System (ADS)

    Gori, Valentina

    2014-05-01

    The CMS experiment has been designed with a 2-level trigger system: the Level 1 Trigger, implemented on custom-designed electronics, and the High Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. A software trigger system requires a tradeoff between the complexity of the algorithms running on the available computing power, the sustainable output rate, and the selection efficiency. Here we will present the performance of the main triggers used during the 2012 data taking, ranging from simpler single-object selections to more complex algorithms combining different objects, and applying analysis-level reconstruction and selection. We will discuss the optimisation of the triggers and the specific techniques to cope with the increasing LHC pile-up, reducing its impact on the physics performance.

  14. The CMS High Level Trigger

    NASA Astrophysics Data System (ADS)

    Trocino, Daniele

    2014-06-01

    The CMS experiment has been designed with a two-level trigger system: the Level-1 Trigger, implemented in custom-designed electronics, and the High-Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. A software trigger system requires a tradeoff between the complexity of the algorithms running with the available computing power, the sustainable output rate, and the selection efficiency. We present the performance of the main triggers used during the 2012 data taking, ranging from simple single-object selections to more complex algorithms combining different objects, and applying analysis-level reconstruction and selection. We discuss the optimisation of the trigger and the specific techniques to cope with the increasing LHC pile-up, reducing its impact on the physics performance.

  15. High resolution x-ray microscope

    SciTech Connect

    Gary, C. K.; Park, H.; Lombardo, L. W.; Piestrup, M. A.; Cremer, J. T.; Pantell, R. H.; Dudchik, Y. I.

    2007-04-30

    The authors present x-ray images of grid meshes and biological material obtained using a microspot x-ray tube with a multilayer optic and a 92-element parabolic compound refractive lens (CRL) made of a plastic containing only hydrogen and carbon. Images obtained using this apparatus are compared with those using an area source with a spherical lens and a spherical lens with multilayer condenser. The authors found the best image quality using the multilayer condenser with a parabolic lens, compared to images with a spherical lens and without the multilayer optics. The resolution was measured using a 155-element parabolic CRL and a multilayer condenser with the microspot tube. The experiment demonstrates about 1.1 {mu}m resolution.

  16. Honey bee protein atlas at organ-level resolution.

    PubMed

    Chan, Queenie W T; Chan, Man Yi; Logan, Michelle; Fang, Yuan; Higo, Heather; Foster, Leonard J

    2013-11-01

    Genome sequencing has provided us with gene lists but cannot tell us where and how their encoded products work together to support life. Complex organisms rely on differential expression of subsets of genes/proteins in organs and tissues, and, in concert, evolved to their present state as they function together to improve an organism's overall reproductive fitness. Proteomics studies of individual organs help us understand their basic functions, but this reductionist approach misses the larger context of the whole organism. This problem could be circumvented if all the organs in an organism were comprehensively studied by the same methodology and analyzed together. Using honey bees (Apis mellifera L.) as a model system, we report here an initial whole proteome of a complex organism, measuring 29 different organ/tissue types among the three honey bee castes: queen, drone, and worker. The data reveal that, e.g., workers have a heightened capacity to deal with environmental toxins and queens have a far more robust pheromone detection system than their nestmates. The data also suggest that workers altruistically sacrifice not only their own reproductive capacity but also their immune potential in favor of their queen. Finally, organ-level resolution of protein expression offers a systematic insight into how organs may have developed. PMID:23878156

  17. Honey bee protein atlas at organ-level resolution

    PubMed Central

    Chan, Queenie W.T.; Chan, Man Yi; Logan, Michelle; Fang, Yuan; Higo, Heather; Foster, Leonard J.

    2013-01-01

    Genome sequencing has provided us with gene lists but cannot tell us where and how their encoded products work together to support life. Complex organisms rely on differential expression of subsets of genes/proteins in organs and tissues, and, in concert, evolved to their present state as they function together to improve an organism's overall reproductive fitness. Proteomics studies of individual organs help us understand their basic functions, but this reductionist approach misses the larger context of the whole organism. This problem could be circumvented if all the organs in an organism were comprehensively studied by the same methodology and analyzed together. Using honey bees (Apis mellifera L.) as a model system, we report here an initial whole proteome of a complex organism, measuring 29 different organ/tissue types among the three honey bee castes: queen, drone, and worker. The data reveal that, e.g., workers have a heightened capacity to deal with environmental toxins and queens have a far more robust pheromone detection system than their nestmates. The data also suggest that workers altruistically sacrifice not only their own reproductive capacity but also their immune potential in favor of their queen. Finally, organ-level resolution of protein expression offers a systematic insight into how organs may have developed. PMID:23878156

  18. High resolution mapping with the FST

    NASA Astrophysics Data System (ADS)

    Bunton, J. D.; Jones, I. G.; Brown, D. R.

    Recent modifications to the Fleurs digital receiver enable the additional correlations between the six 13.7 m dishes to be measured. Previously, only those correlations formed between the four east-west 13.7 m dishes and the thirty-two 5.7 m dishes were measured. This enables the production of three type of maps; each with full 20 arc second resolution but with properties which suit differing astronomical applications.

  19. High resolution alpha particle spectrometry through collimation

    NASA Astrophysics Data System (ADS)

    Park, Seunghoon; Kwak, Sung-Woo; Kang, Han-Byeol

    2015-06-01

    Alpha particle spectrometry with collimation is a useful method for identifying nuclear materials among various nuclides. A mesh type collimator reduces the low energy tail and broadened energy distribution by cutting off particles with a low incidence angle. The relation between the resolution and the counting efficiency can be investigated by changing a ratio of the mesh hole diameter and the collimator thickness. Through collimation, a target particle can be distinguished by a PIPS® detector under a mixture of various nuclides.

  20. High resolution laser mass spectrometry bioimaging.

    PubMed

    Murray, Kermit K; Seneviratne, Chinthaka A; Ghorai, Suman

    2016-07-15

    Mass spectrometry imaging (MSI) was introduced more than five decades ago with secondary ion mass spectrometry (SIMS) and a decade later with laser desorption/ionization (LDI) mass spectrometry (MS). Large biomolecule imaging by matrix-assisted laser desorption/ionization (MALDI) was developed in the 1990s and ambient laser MS a decade ago. Although SIMS has been capable of imaging with a moderate mass range at sub-micrometer lateral resolution from its inception, laser MS requires additional effort to achieve a lateral resolution of 10μm or below which is required to image at the size scale of single mammalian cells. This review covers untargeted large biomolecule MSI using lasers for desorption/ionization or laser desorption and post-ionization. These methods include laser microprobe (LDI) MSI, MALDI MSI, laser ambient and atmospheric pressure MSI, and near-field laser ablation MS. Novel approaches to improving lateral resolution are discussed, including oversampling, beam shaping, transmission geometry, reflective and through-hole objectives, microscope mode, and near-field optics. PMID:26972785

  1. High-resolution mapping of motor vehicle carbon dioxide emissions

    NASA Astrophysics Data System (ADS)

    McDonald, Brian C.; McBride, Zoe C.; Martin, Elliot W.; Harley, Robert A.

    2014-05-01

    A fuel-based inventory for vehicle emissions is presented for carbon dioxide (CO2) and mapped at various spatial resolutions (10 km, 4 km, 1 km, and 500 m) using fuel sales and traffic count data. The mapping is done separately for gasoline-powered vehicles and heavy-duty diesel trucks. Emission estimates from this study are compared with the Emissions Database for Global Atmospheric Research (EDGAR) and VULCAN. All three inventories agree at the national level within 5%. EDGAR uses road density as a surrogate to apportion vehicle emissions, which leads to 20-80% overestimates of on-road CO2 emissions in the largest U.S. cities. High-resolution emission maps are presented for Los Angeles, New York City, San Francisco-San Jose, Houston, and Dallas-Fort Worth. Sharp emission gradients that exist near major highways are not apparent when emissions are mapped at 10 km resolution. High CO2 emission fluxes over highways become apparent at grid resolutions of 1 km and finer. Temporal variations in vehicle emissions are characterized using extensive day- and time-specific traffic count data and are described over diurnal, day of week, and seasonal time scales. Clear differences are observed when comparing light- and heavy-duty vehicle traffic patterns and comparing urban and rural areas. Decadal emission trends were analyzed from 2000 to 2007 when traffic volumes were increasing and a more recent period (2007-2010) when traffic volumes declined due to recession. We found large nonuniform changes in on-road CO2 emissions over a period of ~5 years, highlighting the importance of timely updates to motor vehicle emission inventories.

  2. High resolution, high bandwidth global shutter CMOS area scan sensors

    NASA Astrophysics Data System (ADS)

    Faramarzpour, Naser; Sonder, Matthias; Li, Binqiao

    2013-10-01

    Global shuttering, sometimes also known as electronic shuttering, enables the use of CMOS sensors in a vast range of applications. Teledyne DALSA Global shutter sensors are able to integrate light synchronously across millions of pixels with microsecond accuracy. Teledyne DALSA offers 5 transistor global shutter pixels in variety of resolutions, pitches and noise and full-well combinations. One of the recent generations of these pixels is implemented in 12 mega pixel area scan device at 6 um pitch and that images up to 70 frames per second with 58 dB dynamic range. These square pixels include microlens and optional color filters. These sensors also offer exposure control, anti-blooming and high dynamic range operation by introduction of a drain and a PPD reset gate to the pixel. The state of the art sense node design of Teledyne DALSA's 5T pixel offers exceptional shutter rejection ratio. The architecture is consistent with the requirements to use stitching to achieve very large area scan devices. Parallel or serial digital output is provided on these sensors using on-chip, column-wise analog to digital converters. Flexible ADC bit depth combined with windowing (adjustable region of interest, ROI) allows these sensors to run with variety of resolution/bandwidth combinations. The low power, state of the art LVDS I/O technology allows for overall power consumptions of less than 2W at full performance conditions.

  3. Semantic-based high resolution remote sensing image retrieval

    NASA Astrophysics Data System (ADS)

    Guo, Dihua

    High Resolution Remote Sensing (HRRS) imagery has been experiencing extraordinary development in the past decade. Technology development means increased resolution imagery is available at lower cost, making it a precious resource for planners, environmental scientists, as well as others who can learn from the ground truth. Image retrieval plays an important role in managing and accessing huge image database. Current image retrieval techniques, cannot satisfy users' requests on retrieving remote sensing images based on semantics. In this dissertation, we make two fundamental contributions to the area of content based image retrieval. First, we propose a novel unsupervised texture-based segmentation approach suitable for accurately segmenting HRRS images. The results of existing segmentation algorithms dramatically deteriorate if simply adopted to HRRS images. This is primarily clue to the multi-texture scales and the high level noise present in these images. Therefore, we propose an effective and efficient segmentation model, which is a two-step process. At high-level, we improved the unsupervised segmentation algorithm by coping with two special features possessed by HRRS images. By preprocessing images with wavelet transform, we not only obtain multi-resolution images but also denoise the original images. By optimizing the splitting results, we solve the problem of textons in HRRS images existing in different scales. At fine level, we employ fuzzy classification segmentation techniques with adjusted parameters for different land cover. We implement our algorithm using real world 1-foot resolution aerial images. Second, we devise methodologies to automatically annotate HRRS images based on semantics. In this, we address the issue of semantic feature selection, the major challenge faced by semantic-based image retrieval. To discover and make use of hidden semantics of images is application dependent. One type of the semantics in HRRS image is conveyed by composite

  4. Medusae Fossae Formation - High Resolution Image

    NASA Technical Reports Server (NTRS)

    1998-01-01

    An exotic terrain of wind-eroded ridges and residual smooth surfaces are seen in one of the highest resolution images ever taken of Mars from orbit. The Medusae Fossae formation is believed to be formed of the fragmental ejecta of huge explosive volcanic eruptions. When subjected to intense wind-blasting over hundreds of millions of years, this material erodes easily once the uppermost tougher crust is breached. The crust, or cap rock, can be seen in the upper right part of the picture. The finely-spaced ridges are similar to features on Earth called yardangs, which are formed by intense winds plucking individual grains from, and by wind-driven sand blasting particles off, sedimentary deposits.

    The image was taken on October 30, 1997 at 11:05 AM PST, shortly after the Mars Global Surveyor spacecraft's 31st closest approach to Mars. The image covers an area 3.6 X 21.5 km (2.2 X 13.4 miles) at 3.6 m (12 feet) per picture element--craters only 11 m (36 feet, about the size of a swimming pool) across can be seen. The best Viking view of the area (VO 1 387S34) has a resolution of 240 m/pixel, or 67 times lower resolution than the MOC frame.

    Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

  5. High resolution obtained by photoelectric scanning techniques.

    NASA Technical Reports Server (NTRS)

    Hall, J. S.

    1972-01-01

    Several applications of linear scanning of different types of objects are described; examples include double stars, satellites, the Red Spot of Jupiter and a landing site on the moon. This technique allows one to achieve a gain of about an order of magnitude in resolution over conventional photoelectric techniques; it is also effective in providing sufficient data for removing background effects and for the application of deconvolution procedures. Brief consideration is given to two-dimensional scanning, either at the telescope or of electronographic images in the laboratory. It is suggested that some of the techniques described should be given serious consideration for space applications.

  6. High resolution IVEM tomography of biological specimens

    SciTech Connect

    Sedat, J.W.; Agard, D.A.

    1997-02-01

    Electron tomography is a powerful tool for elucidating the three-dimensional architecture of large biological complexes and subcellular organelles. The introduction of intermediate voltage electron microscopes further extended the technique by providing the means to examine very large and non-symmetrical subcellular organelles, at resolutions beyond what would be possible using light microscopy. Recent studies using electron tomography on a variety of cellular organelles and assemblies such as centrosomes, kinetochores, and chromatin have clearly demonstrated the power of this technique for obtaining 3D structural information on non-symmetric cell components. When combined with biochemical and molecular observations, these 3D reconstructions have provided significant new insights into biological function.

  7. HIGH RESOLUTION PHOTOEMISSION STUDIES OF COMPLEX MATERIALS.

    SciTech Connect

    JOHNSON,P.D.

    1999-10-13

    Recent instrumentation developments in photoemission are providing new insights into the physics of complex materials. With increased energy and momentum resolution, it has become possible to examine in detail different contributions to the self-energy or inverse lifetime of the photohole created in the photoexcitation process, Employing momentum distribution and energy distribution curves, a detailed study of the optimally doped cuprate, Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub g+{delta}}, shows that the material behaves like a non-Fermi liquid with no evidence for the quasi-particles characteristic of a Fermi liquid.

  8. DSCOVR High Time Resolution Solar Wind Measurements

    NASA Technical Reports Server (NTRS)

    Szabo, Adam

    2012-01-01

    The Deep Space Climate Observatory (DSCOVR), previously known as Triana, spacecraft is expected to be launched in late 2014. It will carry a fluxgate magnetometer, Faraday Cup solar wind detector and a top-hat electron electrostatic analyzer. The Faraday Cup will provide an unprecedented 10 vectors/sec time resolution measurement of the solar wind proton and alpha reduced distribution functions. Coupled with the 40 vector/sec vector magnetometer measurements, the identification of specific wave modes in the solar wind will be possible for the first time. The science objectives and data products of the mission will be discussed.

  9. Fine resolution topographic mapping of the Jovian moons: a Ka-band high resolution topographic mapping interferometric synthetic aperture radar

    NASA Technical Reports Server (NTRS)

    Madsen, Soren N.; Carsey, Frank D.; Turtle, Elizabeth P.

    2003-01-01

    The topographic data set obtained by MOLA has provided an unprecedented level of information about Mars' geologic features. The proposed flight of JIMO provides an opportunity to accomplish a similar mapping of and comparable scientific discovery for the Jovian moons through us of an interferometric imaging radar analogous to the Shuttle radar that recently generated a new topographic map of Earth. A Ka-band single pass across-track synthetic aperture radar (SAR) interferometer can provide very high resolution surface elevation maps. The concept would use two antennas mounted at the ends of a deployable boom (similar to the Shuttle Radar Topographic Mapper) extended orthogonal to the direction of flight. Assuming an orbit altitude of approximately 100 km and a ground velocity of approximately 1.5 km/sec, horizontal resolutions at the 10 meter level and vertical resolutions at the sub-meter level are possible.

  10. Fine Resolution Topographic Mapping of the Jovian Moons: A Ka-Band High Resolution Topographic Mapping Interferometric Synthetic Aperture Radar

    NASA Technical Reports Server (NTRS)

    Madsen, S. N.; Carsey, F. D.; Turtle, E. P.

    2003-01-01

    The topographic data set obtained by MOLA has provided an unprecedented level of information about Mars' geologic features. The proposed flight of JIMO provides an opportunity to accomplish a similar mapping of and comparable scientific discovery for the Jovian moons through use of an interferometric imaging radar analogous to the Shuttle radar that recently generated a new topographic map of Earth. A Ka-band single pass across-track synthetic aperture radar (SAR) interferometer can provide very high resolution surface elevation maps. The concept would use two antennas mounted at the ends of a deployable boom (similar to the Shuttle Radar Topographic Mapper) extended orthogonal to the direction of flight. Assuming an orbit altitude of approximately 100km and a ground velocity of approximately 1.5 km/sec, horizontal resolutions at the 10 meter level and vertical resolutions at the sub-meter level are possible.

  11. High Resolution Chemical Study of ALH84001

    NASA Technical Reports Server (NTRS)

    Conrad, Pamela G.; Douglas, Susanne; Kuhlman, Kimberly R.

    2001-01-01

    We have studied the chemistry of a sample of the SNC meteorite ALH84001 using an environmental scanning electron microscope (ESEM) with an energy dispersive chemical analytical detector and a focused ion beam secondary ion mass spectrometer (FIB-SIMS). Here we present the chemical data, both spectra and images, from two techniques that do not require sample preparation with a conductive coating, thus eliminating the possibility of preparation-induced textural artifacts. The FIB-SIMS instrument includes a column optimized for SEM with a quadrupole type mass spectrometer. Its spatial and spectral resolution are 20 nm and 0.4 AMU, respectively. The spatial resolution of the ESEM for chemical analysis is about 100 nm. Limits of detection for both instruments are mass dependent. Both the ESEM and the FIB-SIMS instrument revealed contrasting surficial features; crumbled, weathered appearance of the matrix in some regions as well as a rather ubiquitous presence of euhedral halite crystals, often associated with cracks or holes in the surface of the rock. Other halogen elements present in the vicinity of the NaCl crystals include K and Br. In this report, elemental inventories are shown as mass spectra and as X-ray maps.

  12. High-resolution X-ray Multilayers

    SciTech Connect

    Martynov, V.V.; Platonov, Yu.; Kazimirov, A.; Bilderback, D.H.

    2004-05-12

    Two new approaches are taken in multilayer fabrication to help bridge the gap in bandwidth between traditional multilayers (1 to 2%) and perfect crystals (0.01%). The first approach is based on creating many layers of low-contrast Al2O3/ B4C materials. The second approach is based on using multilayer structures with a small d-spacing using traditional W/B4C and Mo/B4C materials. With 8 keV x-rays on the Chess A2 beamline, we measured a bandwidth of 0.27% with a reflectivity of 40% and a Darwin width of 17 arc seconds from a 26 A d-spacing multilayer with 800 bi-layers of Al2O3/B4C using the low-contrast approach. On the other hand, the short period approach with a W/B4C multilayer and a 14.8 A d-spacing showed a resolution of 0.5 % and a reflectivity of 58.5%. Two more Mo/B4C samples with d-spacings of 15 A and 20 A showed energy resolutions of 0.25% and 0.52% with corresponding reflectivities of 39% and 66%. Thus we observe that both methods can produce useful x-ray optical components.

  13. High Resolution Millimeter Wavelength Polarimetry at BIMA

    NASA Astrophysics Data System (ADS)

    Rao, R.; Crutcher, R. M.; Plambeck, R. L.; Wright, M. C. H.

    1998-05-01

    Polarimetry at far-infrared, sub-millimeter and millimeter wavelengths is a useful probe of the magnetic field structure in regions of star formation. However, most previous polarization observations have been conducted with single dish telescopes (KAO, CSO, JCMT, NRAO 12-meter) with limited angular resolution (greater than 20arcsec ). Polarization observations with interferometer arrays can provide higher angular resolution (about 4arcsec ) images of star-forming regions. We present here the details of a polarimetry system constructed for the Berkeley-Illinois-Maryland Association (BIMA) millimeter array at Hat Creek (California) operating at wavelengths of 3.3 mm (90 GHz) and 1.3 mm (230 GHz). The polarizing element is a quarter wave plate made of Rexolite (cross-linked polystyrene) which has a diectric constant of approximately 2.55. The instrumental response, which is frequency-dependent since the polarizer is chromatic, has been determined to an accuracy of 0.3%. The polarimeter has also been used to monitor a select sample of quasars to determine their time variability. These quasar polarization data complement lower frequency monitoring surveys (less than 15 GHz) and constrain the emission models and magnetic field topology deduced for these objects.

  14. Precision Viticulture from Multitemporal, Multispectral Very High Resolution Satellite Data

    NASA Astrophysics Data System (ADS)

    Kandylakis, Z.; Karantzalos, K.

    2016-06-01

    In order to exploit efficiently very high resolution satellite multispectral data for precision agriculture applications, validated methodologies should be established which link the observed reflectance spectra with certain crop/plant/fruit biophysical and biochemical quality parameters. To this end, based on concurrent satellite and field campaigns during the veraison period, satellite and in-situ data were collected, along with several grape samples, at specific locations during the harvesting period. These data were collected for a period of three years in two viticultural areas in Northern Greece. After the required data pre-processing, canopy reflectance observations, through the combination of several vegetation indices were correlated with the quantitative results from the grape/must analysis of grape sampling. Results appear quite promising, indicating that certain key quality parameters (like brix levels, total phenolic content, brix to total acidity, anthocyanin levels) which describe the oenological potential, phenolic composition and chromatic characteristics can be efficiently estimated from the satellite data.

  15. High Resolution X-ray Imaging

    NASA Technical Reports Server (NTRS)

    Cash, Webster

    2002-01-01

    NAG5-5020 covered a period of 7.5 years during which a great deal of progress was made in x-ray optical techniques under this grant. We survived peer review numerous times during the effort to keep the grant going. In 1994, when the grant started we were actively pursuing the application of spherical mirrors to improving x-ray telescopes. We had found that x-ray detectors were becoming rapidly more sophisticated and affordable, but that x-ray telescopes were only being improved through the intense application of money within the AXAF program. Clearly new techniques for the future were needed. We were successful in developing and testing at the HELSTF facility in New Mexico a four reflection coma-corrected telescope made from spheres. We were able to demonstrate 0.3 arcsecond resolution, almost to the diffraction limit of the system. The community as a whole was, at that time, not particularly interested in looking past AXAF (Chandra) and the effort needed to evolve. Since we had reached the diffraction limit using non-Wolter optics we then decided to see if we could build an x-ray interferometer in the laboratory. In the lab the potential for improved resolution was substantial. If synthetic aperture telescopes could be built in space, then orders of magnitude improvement would become feasible. In 1998 NASA, under the direction of Dr Nick White of Goddard, started a study to assess the potential and feasibility of x-ray interferometry in space. My work became of central interest to the committee because it indicated that such was possible. In early 1999 we had the breakthrough that allowed us build a practical interferometer. By using flats and hooking up with the Marshall Space Flight Center facilities we were able to demonstrate fringes at 1.25keV on a one millimeter baseline. This actual laboratory demonstration provided the solid proof of concept that NASA needed. As the year progressed the future of x-ray astronomy jelled around the Maxim program. Maxim is a

  16. Modified Noise Power Ratio testing of high resolution digitizers

    SciTech Connect

    McDonald, T.S.

    1994-05-01

    A broadband, full signal range, side-by-side (tandem) test method for estimating the internal noise performance of high resolution digitizers is described and illustrated. The technique involves a re-definition of the traditional Noise Power Ratio (NPR) test, a change that not only makes this test applicable to higher resolution systems than was previously practical, but also enhances its value and flexibility. Since coherence analysis is the basis of this new definition, and since the application of coherence procedures to high resolution data poses several problems, this report discusses these problems and their resolution.

  17. The high spectral resolution (scanning) lidar (HSRL)

    SciTech Connect

    Eloranta, E.

    1995-09-01

    Lidars enable the spatial resolution of optical depth variation in clouds. The optical depth must be inverted from the backscatter signal, a process which is complicated by the fact that both molecular and aerosol backscatter signals are present. The HSRL has the advantage of allowing these two signals to be separated. It has a huge dynamic range, allowing optical depth retrieval for t = 0.01 to 3. Depolarization is used to determine the nature of hydrometeors present. Experiments show that water clouds must almost always be taken into account during cirrus observations. An exciting new development is the possibility of measuring effective radius via diffraction peak width and variable field-of-view measurements. 2 figs.

  18. High Spectral Resolution With Multilayer Gratings

    SciTech Connect

    Andre, J.-M.; Le Guen, K.; Jonnard, P.

    2010-04-06

    The improvement of spectral resolution brought about by the use of multilayer grating (MG) instead of multilayer mirror (MM) is analyzed. The spectrum of a complex sample containing various elements excited under electron irradiation is studied. This sample is a pellet made by pressing powders of Cu and compounds with Fe and F atoms. The MM is a Mo/B{sub 4}C periodic multilayer with a period of about 6 nm; for the MG a grating of 1 {mu}m period has been etched in the MM. It is shown that the MG can easily resolve the F Kalpha and Fe Lalpha emissions, separated by about 30 eV, whereas the MM is unable to give such a performance. A comparison with an EDS (SDD) detector is also given. It is also shown that the MG can improve the detection limit. Finally the role of the slit placed in front of the detector is discussed.

  19. Galileo high-resolution encoder system

    NASA Astrophysics Data System (ADS)

    Mancini, Dario; Cascone, Enrico; Schipani, Pietro

    1997-09-01

    The Galileo National Telescope (TNG) is a 3.6 meter Alt-Az telescope installed at the Astronomical Observatory of the Roque de Los Muchachos in La Palma, Canary Islands (Spain). The TNG motion control system, designed and realized by the Technology Working Group (TWG), is completely digital because of the versatility of this system topology. In a digital control system using an encoder as transducer means to have a digital feedback signal, therefore directly comparable with the reference without any conversion that is essential with other kinds of transducers. In the following the Galileo telescope (TNG) encoder system with its control electronics and the management software are described. It has been realized by a collaboration between the Heidenhain Company and the TWG. The TNG encoder system, at the state of the art, has one of the highest performances in the telescopes field, in terms of resolution, accuracy, readout time, reliability.

  20. Robust Tips for High Resolution Chemical Imaging

    NASA Astrophysics Data System (ADS)

    Barrios, Carlos; Malkovskiy, Andrey; Kisliuk, Alexander; Sokolov, Alexei; Foster, Mark

    2009-03-01

    Tip enhanced Raman spectroscopy (TERS) combines scanning probe microscopy with Raman spectroscopy, taking advantage of apertureless near-field optics. A plasmonic structure at the apex of a sharp tip provides signal amplification required for chemical imaging. Plasmonic structure characteristics such as roughness, shape, and radius determine the spatial resolution and signal enhancement. Unfortunately, noble metal nanostructures have limited lifetimes due to mechanical, chemical, and thermal degradation. Lifetime extension requires slowing degradation processes while minimizing unfavorable influences on the optical response. An ultrathin SiOx protective coating provides lifetime improvement of silver plasmonic nanostructures on SPM tips. Controlled physical vapor deposition (PVD) of Al can be used to create ultrathin (˜2-3 nm) Al2O3 coatings that improve significantly the stability and wear resistance of plasmonics structures without substantial degradation of optical properties. Such a coating completely prevented decay in plasmonic activity after 40 days of use.

  1. High Resolution X-ray Imaging

    NASA Technical Reports Server (NTRS)

    Cash, Webster

    2002-01-01

    NAG5-5020 covered a period of 7.5 years during which a great deal of progress was made in x-ray optical techniques under this grant. We survived peer review numerous times during the effort to keep the grant going. In 1994, when the grant started we were actively pursuing the application of spherical mirrors to improving x-ray telescopes. We had found that x-ray detectors were becoming rapidly more sophisticated and affordable, but that x-ray telescopes were only being improved through the intense application of money within the AXAF program. Clearly new techniques for the future were needed. We were successful in developing and testing at the HELSTF facility in New Mexico a four reflection coma-corrected telescope made from spheres. We were able to demonstrate 0.3 arcsecond resolution, almost to the diffraction limit of the system. The community as a whole was, at that time, not particularly interested in looking past AXAF (Chandra) and the effort needed to evolve. Since we had reached the diffraction limit using non-Wolter optics we then decided to see if we could build an x-ray interferometer in the laboratory. In the lab the potential for improved resolution was substantial. If synthetic aperture telescopes could be built in space, then orders of magnitude improvement would become feasible. In 1998 NASA, under the direction of Dr. Nick White of Goddard, started a study to assess the potential and feasibility of x-ray interferometry in space. My work became of central interest to the committee because it indicated that such was possible. In early 1999 we had the breakthrough that allowed us build a practical interferometer. By using flats and hooking up with the Marshall Space Flight Center facilities we were able to demonstrate fringes at 1.25keV on a one millimeter baseline. This actual laboratory demonstration provided the solid proof of concept that NASA needed.

  2. Spontaneous Raman scattering as a high resolution XUV radiation source

    NASA Technical Reports Server (NTRS)

    Rothenberg, J. E.; Young, J. F.; Harris, S. E.

    1983-01-01

    A type of high resolution XUV radiation source is described which is based upon spontaneous anti-Stokes scattering of tunable incident laser radiation from atoms excited to metastable levels. The theory of the source is summarized and two sets of experiments using He (1s2s)(1)S atoms, produced in a cw hollow cathode and in a pulsed high power microwave discharge, are discussed. The radiation source is used to examine transitions originating from the 3p(6) shell of potassium. The observed features include four previously unreported absorption lines and several sharp interferences of closely spaced autoionizing lines. A source linewidth of about 1.9 cm(-1) at 185,000 cm(-1) is demonstrated.

  3. Theoretical performance analysis for CMOS based high resolution detectors.

    PubMed

    Jain, Amit; Bednarek, Daniel R; Rudin, Stephen

    2013-03-01

    High resolution imaging capabilities are essential for accurately guiding successful endovascular interventional procedures. Present x-ray imaging detectors are not always adequate due to their inherent limitations. The newly-developed high-resolution micro-angiographic fluoroscope (MAF-CCD) detector has demonstrated excellent clinical image quality; however, further improvement in performance and physical design may be possible using CMOS sensors. We have thus calculated the theoretical performance of two proposed CMOS detectors which may be used as a successor to the MAF. The proposed detectors have a 300 μm thick HL-type CsI phosphor, a 50 μm-pixel CMOS sensor with and without a variable gain light image intensifier (LII), and are designated MAF-CMOS-LII and MAF-CMOS, respectively. For the performance evaluation, linear cascade modeling was used. The detector imaging chains were divided into individual stages characterized by one of the basic processes (quantum gain, binomial selection, stochastic and deterministic blurring, additive noise). Ranges of readout noise and exposure were used to calculate the detectors' MTF and DQE. The MAF-CMOS showed slightly better MTF than the MAF-CMOS-LII, but the MAF-CMOS-LII showed far better DQE, especially for lower exposures. The proposed detectors can have improved MTF and DQE compared with the present high resolution MAF detector. The performance of the MAF-CMOS is excellent for the angiography exposure range; however it is limited at fluoroscopic levels due to additive instrumentation noise. The MAF-CMOS-LII, having the advantage of the variable LII gain, can overcome the noise limitation and hence may perform exceptionally for the full range of required exposures; however, it is more complex and hence more expensive. PMID:24353390

  4. High-resolution studies of atmospheric IR emission spectra

    NASA Technical Reports Server (NTRS)

    Murcray, F. J.; Murcray, F. H.; Goldman, A.; Blatherwick, R. D.; Murcray, D. G.

    1991-01-01

    Atmospheric emission spectra obtained with two different spectrometer systems are presented. The first system (the BOMEM Michelson interferometer) is designed for emission work. Spectra were obtained under adverse conditions in the Antarctic, and are still of good absolute accuracy. The second system (a modified Bruker Instruments IFS120 very high spectral resolution interferometer) demonstrates the sensitivity that can be achieved even at higher spectral resolution. This system shows that mid-IR atmospheric emission spectra can be obtained with a good SNR in a reasonable length of time at a relatively high resolution. A properly designed high resolution system should achieve high accuracy, sensitivity, and resolution, thereby permitting measurements of many atmospheric constituents when solar spectra cannot be obtained.

  5. Proteogenomic analysis of Mycobacterium tuberculosis by high resolution mass spectrometry.

    PubMed

    Kelkar, Dhanashree S; Kumar, Dhirendra; Kumar, Praveen; Balakrishnan, Lavanya; Muthusamy, Babylakshmi; Yadav, Amit Kumar; Shrivastava, Priyanka; Marimuthu, Arivusudar; Anand, Sridhar; Sundaram, Hema; Kingsbury, Reena; Harsha, H C; Nair, Bipin; Prasad, T S Keshava; Chauhan, Devendra Singh; Katoch, Kiran; Katoch, Vishwa Mohan; Kumar, Prahlad; Chaerkady, Raghothama; Ramachandran, Srinivasan; Dash, Debasis; Pandey, Akhilesh

    2011-12-01

    The genome sequencing of H37Rv strain of Mycobacterium tuberculosis was completed in 1998 followed by the whole genome sequencing of a clinical isolate, CDC1551 in 2002. Since then, the genomic sequences of a number of other strains have become available making it one of the better studied pathogenic bacterial species at the genomic level. However, annotation of its genome remains challenging because of high GC content and dissimilarity to other model prokaryotes. To this end, we carried out an in-depth proteogenomic analysis of the M. tuberculosis H37Rv strain using Fourier transform mass spectrometry with high resolution at both MS and tandem MS levels. In all, we identified 3176 proteins from Mycobacterium tuberculosis representing ~80% of its total predicted gene count. In addition to protein database search, we carried out a genome database search, which led to identification of ~250 novel peptides. Based on these novel genome search-specific peptides, we discovered 41 novel protein coding genes in the H37Rv genome. Using peptide evidence and alternative gene prediction tools, we also corrected 79 gene models. Finally, mass spectrometric data from N terminus-derived peptides confirmed 727 existing annotations for translational start sites while correcting those for 33 proteins. We report creation of a high confidence set of protein coding regions in Mycobacterium tuberculosis genome obtained by high resolution tandem mass-spectrometry at both precursor and fragment detection steps for the first time. This proteogenomic approach should be generally applicable to other organisms whose genomes have already been sequenced for obtaining a more accurate catalogue of protein-coding genes. PMID:21969609

  6. Whole-animal imaging with high spatio-temporal resolution

    NASA Astrophysics Data System (ADS)

    Chhetri, Raghav; Amat, Fernando; Wan, Yinan; Höckendorf, Burkhard; Lemon, William C.; Keller, Philipp J.

    2016-03-01

    We developed isotropic multiview (IsoView) light-sheet microscopy in order to image fast cellular dynamics, such as cell movements in an entire developing embryo or neuronal activity throughput an entire brain or nervous system, with high resolution in all dimensions, high imaging speeds, good physical coverage and low photo-damage. To achieve high temporal resolution and high spatial resolution at the same time, IsoView microscopy rapidly images large specimens via simultaneous light-sheet illumination and fluorescence detection along four orthogonal directions. In a post-processing step, these four views are then combined by means of high-throughput multiview deconvolution to yield images with a system resolution of ≤ 450 nm in all three dimensions. Using IsoView microscopy, we performed whole-animal functional imaging of Drosophila embryos and larvae at a spatial resolution of 1.1-2.5 μm and at a temporal resolution of 2 Hz for up to 9 hours. We also performed whole-brain functional imaging in larval zebrafish and multicolor imaging of fast cellular dynamics across entire, gastrulating Drosophila embryos with isotropic, sub-cellular resolution. Compared with conventional (spatially anisotropic) light-sheet microscopy, IsoView microscopy improves spatial resolution at least sevenfold and decreases resolution anisotropy at least threefold. Compared with existing high-resolution light-sheet techniques, such as lattice lightsheet microscopy or diSPIM, IsoView microscopy effectively doubles the penetration depth and provides subsecond temporal resolution for specimens 400-fold larger than could previously be imaged.

  7. Tensorially consistent microleveling of high resolution full tensor gradiometry data

    NASA Astrophysics Data System (ADS)

    Schiffler, M.; Queitsch, M.; Schneider, M.; Stolz, R.; Krech, W.; Meyer, H.; Kukowski, N.

    2013-12-01

    Full Tensor Magnetic Gradiometry (FTMG) data obtained with Superconductive Quantum Interference Device (SQUID) sensors offer high resolution and a low signal-to-noise ratio. In airborne operation, processing steps for leveling of flight lines using tie-lines and subsequent micro-leveling become important. Airborne SQUID-FTMG surveys show that in magnetically calm regions the overall measurement system noise level of ≈10pT/m RMS is the main contribution to the magnetograms and line-dependent artifacts become visible. Both tie-line and micro-leveling are used to remove these artifacts (corrugations). But, in the application of these standard leveling routines - originally designed for total magnetic intensity measurements - to the tensor components independently, the tracelessness and the symmetry of the resulting corrected tensor is not preserved. We show that tie-line leveling for airborne SQUID-FTMG data can be surpassed using the presented micro-leveling algorithm and discuss how it is designed to preserve the tensor properties. The micro-leveling process is performed via a moving median filter using a geometric median which preserves the properties of the tensor either to the entire tensor at once or to its structural part (eigenvalues) and rotational part (eigenvectors or idempotences) independently. We discuss the impact on data quality for the different micro-leveling methods. At each observation point, the median along the distance of the flight line is subtracted and the median in a specific footprint radius is added. For application of this filter to the rotational states, we use quaternions and quaternion interpolation. Examples of the new processing methods on data acquired with the FTMG system will be presented in this work.

  8. Teaching Conflict Resolution Skills to Middle and High School Students through Interactive Drama and Role Play

    ERIC Educational Resources Information Center

    Graves, Kelly N.; Frabutt, James M.; Vigliano, Debra

    2007-01-01

    In response to the rising levels of school conflict, the present study investigated a new approach to conflict resolution for middle and high school students using interactive drama and role play called the Win-Win Resolutions program. The standardized curriculum delivered within the school setting includes strategies for self-control and anger…

  9. Towards high-resolution mantle convection simulations

    NASA Astrophysics Data System (ADS)

    Höink, T.; Richards, M. A.; Lenardic, A.

    2009-12-01

    The motion of tectonic plates at the Earth’s surface, earthquakes, most forms of volcanism, the growth and evolution of continents, and the volatile fluxes that govern the composition and evolution of the oceans and atmosphere are all controlled by the process of solid-state thermal convection in the Earth’s rocky mantle, with perhaps a minor contribution from convection in the iron core. Similar processes govern the evolution of other planetary objects such as Mars, Venus, Titan, and Europa, all of which might conceivably shed light on the origin and evolution of life on Earth. Modeling and understanding this complicated dynamical system is one of the true “grand challenges” of Earth and planetary science. In the past three decades much progress towards understanding the dynamics of mantle convection has been made, with the increasing aid of computational modeling. Numerical sophistication has evolved significantly, and a small number of independent codes have been successfully employed. Computational power continues to increase dramatically, and with it the ability to resolve increasingly finer fluid mechanical structures. Yet, the perhaps most often cited limitation in numerical modeling based publications is still the limitation of computing power, because the ability to resolve thermal boundary layers within the convecting mantle (e.g., lithospheric plates), requires a spatial resolution of ~ 10 km. At present, the largest supercomputing facilities still barely approach the power to resolve this length scale in mantle convection simulations that include the physics necessary to model plate-like behavior. Our goal is to use supercomputing facilities to perform 3D spherical mantle convection simulations that include the ingredients for plate-like behavior, i.e. strongly temperature- and stress-dependent viscosity, at Earth-like convective vigor with a global resolution of order 10 km. In order to qualify to use such facilities, it is also necessary to

  10. Cheetah: A high frame rate, high resolution SWIR image camera

    NASA Astrophysics Data System (ADS)

    Neys, Joel; Bentell, Jonas; O'Grady, Matt; Vermeiren, Jan; Colin, Thierry; Hooylaerts, Peter; Grietens, Bob

    2008-10-01

    A high resolution, high frame rate InGaAs based image sensor and associated camera has been developed. The sensor and the camera are capable of recording and delivering more than 1700 full 640x512pixel frames per second. The FPA utilizes a low lag CTIA current integrator in each pixel, enabling integration times shorter than one microsecond. On-chip logics allows for four different sub windows to be read out simultaneously at even higher rates. The spectral sensitivity of the FPA is situated in the SWIR range [0.9-1.7 μm] and can be further extended into the Visible and NIR range. The Cheetah camera has max 16 GB of on-board memory to store the acquired images and transfer the data over a Gigabit Ethernet connection to the PC. The camera is also equipped with a full CameralinkTM interface to directly stream the data to a frame grabber or dedicated image processing unit. The Cheetah camera is completely under software control.

  11. Towards high resolution soil property maps for Austria

    NASA Astrophysics Data System (ADS)

    Schürz, Christoph; Klotz, Daniel; Herrnegger, Mathew; Schulz, Karsten

    2015-04-01

    Soil hydraulic properties, such as soil texture, soil water retention characteristics, hydraulic conductivity, or soil depth are important inputs for hydrologic catchment modelling. However, the availability of such data in Austria is often insufficient to fulfill requirements of well-established hydrological models. Either, soil data is available in sufficient spatial resolution but only covers a small extent of the considered area, or the data is comprehensive but rather coarse in its spatial resolution. Furthermore, the level of detail and quality of the data differs between the available data sets. In order to generate a comprehensive soil data set for whole Austria that includes main soil physical properties, as well as soil depth and organic carbon content in a high spatial resolution (10x10 to 100x100m²) several available soil data bases are merged and harmonized. Starting point is a high resolution soil texture map that only covers agricultural areas and is available due to Austrian land appraisal. Soil physical properties for those areas are derived by applying pedotransfer functions (e.g. Saxton and Rawls, 2006) resulting in expectation values and quantiles of the respective property for each soil texture class. For agricultural areas where no texture information is available, the most likely soil texture is assigned applying a Bayesian network approach incorporating information such as elevation, soil slope, soil type, or hydro-geology at different spatial scales. Soil data for forested areas, that cover a large extent of the state territory, are rather sparse in Austria. For such areas a similar approach as for agricultural areas is applied by using a Bayesian network for prediction of the soil texture. Additionally, information to various soil parameters taken from literature is incorporated. For areas that are covered by land use different to agriculture or forestry, such as bare rock surfaces, or wetland areas, solely literature information is used

  12. Eigenvector pruning method for high resolution beamforming.

    PubMed

    Quijano, Jorge E; Zurk, Lisa M

    2015-10-01

    This paper introduces an eigenvector pruning algorithm for the estimation of the signal-plus-interference eigenspace, required as a preliminary step to subspace beamforming. The proposed method considers large-aperture passive array configurations operating in environments with multiple maneuvering targets in background noise, in which the available data for estimation of sample covariances and eigenvectors are limited. Based on statistical properties of scalar products between deterministic and complex random vectors, this work defines a statistically justified threshold to identify target-related features embedded in the sample eigenvectors, leading to an estimator for the signal-bearing eigenspace. It is shown that data projection into this signal subspace results in sharpening of beamforming outputs corresponding to closely spaced targets and provides better target separation compared to current subspace beamformers. In addition, the proposed threshold gives the user control over the worst-case scenario for the number of false detections by the beamformer. Simulated data are used to quantify the performance of the subspace estimator according to the distance between estimated and true signal subspaces. Beamforming resolution using the proposed method is analyzed with simulated data corresponding to a horizontal line array, as well as experimental data from the Shallow Water Array Performance experiment. PMID:26520298

  13. High-resolution time-frequency distributions for fall detection

    NASA Astrophysics Data System (ADS)

    Amin, Moeness G.; Zhang, Yimin D.; Boashash, Boualem

    2015-05-01

    In this paper, we examine the role of high-resolution time-frequency distributions (TFDs) of radar micro-Doppler signatures for fall detection. The work supports the recent and rising interest in using emerging radar technology for elderly care and assisted living. Spectrograms have been the de facto joint-variable signal representation, depicting the signal power in both time and frequency. Although there have been major advances in designing quadratic TFDs which are superior to spectrograms in terms of detailing the local signal behavior, the contributions of these distributions in the area of human motion classifications and their offerings in enhanced feature extractions have not yet been properly evaluated. The main purpose of this paper is to show the effect of using high-resolution TFD kernels, in lieu of spectrogram, on fall detection. We focus on the extended modified B-distribution (EMBD) and exploit the level of details it provides as compared with the coarse and smoothed time-frequency signatures offered by spectrograms.

  14. Low-dose high-resolution CT of lung parenchyma

    SciTech Connect

    Zwirewich, C.V.; Mayo, J.R.; Mueller, N.L. )

    1991-08-01

    To evaluate the efficacy of low-dose high-resolution computed tomography (HRCT) in the assessment of lung parenchyma, three observers reviewed the scans of 31 patients. The 1.5-mm-collimation, 2-second, 120-kVp scans were obtained at 20 and 200 mA at selected identical levels in the chest. The observers evaluated the visualization of normal pulmonary anatomy, various parenchymal abnormalities and their distribution, and artifacts. The low-dose and conventional scans were equivalent in the evaluation of vessels, lobar and segmental bronchi, and anatomy of secondary pulmonary lobules, and in characterizing the extent and distribution of reticulation, honeycomb cysts, and thickened interlobular septa. The low-dose technique failed to demonstrate ground-glass opacity in two of 10 cases (20%) and emphysema in one of nine cases (11%), in which they were evident but subtle on the high-dose scans. These differences were not statistically significant. Linear streak artifact was more prominent on images acquired with the low-dose technique, but the two techniques were judged equally diagnostic in 97% of cases. The authors conclude that HRCT images acquired at 20 mA yield anatomic information equivalent to that obtained with 200-mA scans in the majority of patients, without significant loss of spatial resolution or image degradation due to linear streak artifact.

  15. High resolution coherence analysis between planetary and climate oscillations

    NASA Astrophysics Data System (ADS)

    Scafetta, Nicola

    2016-05-01

    This study investigates the existence of a multi-frequency spectral coherence between planetary and global surface temperature oscillations by using advanced techniques of coherence analysis and statistical significance tests. The performance of the standard Matlab mscohere algorithms is compared versus high resolution coherence analysis methodologies such as the canonical correlation analysis. The Matlab mscohere function highlights large coherence peaks at 20 and 60-year periods although, due to the shortness of the global surface temperature record (1850-2014), the statistical significance of the result depends on the specific window function adopted for pre-processing the data. In fact, window functions disrupt the low frequency component of the spectrum. On the contrary, using the canonical correlation analysis at least five coherent frequencies at the 95% significance level are found at the following periods: 6.6, 7.4, 14, 20 and 60 years. Thus, high resolution coherence analysis confirms that the climate system can be partially modulated by astronomical forces of gravitational, electromagnetic and solar origin. A possible chain of the physical causes explaining this coherence is briefly discussed.

  16. High-resolution medical ultrasound arrays using smart materials technology

    NASA Astrophysics Data System (ADS)

    Bridger, Keith; Caldwell, Paul J.; Kuhn, Phillip; Winzer, Stephen R.

    1996-05-01

    Current ultrasound images have relatively low contrast (high levels of clutter) and resolution. Image quality could be dramatically improved if 2D ultrasound transducer arrays were available to perform the scans. These improvements would come from reducing clutter by eliminating target echoes that the beam width of a 1D array causes to be superimposed on a scan plane, and enhancing resolution by enabling the use of algorithms which correct the wavefront distortion introduced by propagation through tissue. The advent of 2D arrays would also enable 3D images to be displayed--eventually in real time. The fabrication of 2D ultrasound arrays is, however, very difficult. This stems from the acoustic requirements of the array (aperture, pitch and element size) which combine together to dictate large numbers (> 1000) of very-low capacitance (< 10 pF) elements. The technology problems revolve around interconnecting the elements and reducing signal losses due to stray capacitance and impedance mismatch. This paper will show how the development of composite smart materials involving the integration of electromechanical elements with electronics is being extended to the development of relatively-inexpensive high-sensitivity 2D ultrasound arrays.

  17. High resolution airborne geophysics at hazardous waste disposal sites

    SciTech Connect

    Beard, L.P.; Nyquist, J.E.; Doll, W.E.; Chong Foo, M.; Gamey, T.J.

    1995-06-01

    In 1994, a high resolution helicopter geophysical survey was conducted over portions of the Oak Ridge Reservation, Tennessee. The 1800 line kilometer survey included multi-frequency electromagnetic and magnetic sensors. The areas covered by the high resolution portion of the survey were selected on the basis of their importance to the environmental restoration effort and on data obtained from the reconnaissance phase of the airborne survey in which electromagnetic, magnetic, and radiometric data were collected over the entire Oak Ridge Reservation in 1992--1993. The high resolution phase had lower sensor heights, more and higher EM frequencies, and tighter line spacings than did the reconnaissance survey. When flying over exceptionally clear areas, the high resolution bird came within a few meters of the ground surface. Unfortunately, even sparse trees and power or phone lines could prevent the bird from being towed safely at low altitude, and over such areas it was more usual for it to be flown at about the same altitude as the bird in the reconnaissance survey, about 30m. Even so, the magnetometers used in the high resolution phase were 20m closer to the ground than in the reconnaissance phase because they were mounted on the tail of the bird rather than on the tow cable above the bird. The EM frequencies used in the high resolution survey ranged from 7400Hz to 67000Hz. Only the horizontal coplanar loop configuration was used in the high resolution flyovers.

  18. [High resolution scanning electron microscopy of isolated outer hair cells].

    PubMed

    Koitschev, A; Müller, H

    1996-11-01

    Isolated hair cell preparations have gained wide acceptance as a model for studying physiological and molecular properties of the sensory cells involved in the hearing process. Ultrastructural details, such as stereocilia links, lateral membrane substructure or synaptic links are of crucial importance for normal sensory transduction. For this reason, we developed a high-resolution scanning electron microscopy (SEM) procedure to study the surface of isolated hair cells. Cells were mechanically and/or enzymatically separated, isolated and immobilized on cover slips by alcian blue and fixed by 2% glutardialdehyde or 1% OsO4. After dehydration, preparations were critical point-dried and sputter-coated with gold-palladium (2-4 nm). Up to 5 nm resolution was achieved. Optimal fixation kept the cells in their typical cylindrical forms. Preservation of the stereocilia and the apical plates of the outer hair cells depended strongly on the fixation process. Tip- and side-links were observed only sporadically because of the aggressive preparation procedure. The lateral plasma membranes of the cell bodies showed regular granular structures of 5-7 nm diameter at maximal magnification. The granular structure of the cell membrane seemed to correspond to putative transmembrane proteins believed to generate membrane-based motility. The remnants of the nerve endings and/or supporting cells usually covered the cell base. The preservation of the cells was better when enzymatic isolation was omitted. The technique used allowed for high resolution ultrastructural examination of isolated hair cells and, when combined with immunological labeling, may permit the identification of proteins at a molecular level. PMID:9064297

  19. Reproducible high-resolution multispectral image acquisition in dermatology

    NASA Astrophysics Data System (ADS)

    Duliu, Alexandru; Gardiazabal, José; Lasser, Tobias; Navab, Nassir

    2015-07-01

    Multispectral image acquisitions are increasingly popular in dermatology, due to their improved spectral resolution which enables better tissue discrimination. Most applications however focus on restricted regions of interest, imaging only small lesions. In this work we present and discuss an imaging framework for high-resolution multispectral imaging on large regions of interest.

  20. High resolution data base for use with MAP

    SciTech Connect

    Tapley, W.C.; Harris, D.B.

    1987-05-05

    A high resolution cartographic data base of thw World is available from the CIA. We obtained this data, extracted portions of the data, and produced cartographic files of varying resolutions. The resulting data files are of the proper format for use with MAP (2), our in-house cartographic plotting program.

  1. Ultrastable reference pulser for high-resolution spectrometers

    NASA Technical Reports Server (NTRS)

    Brenner, R.; Lenkszus, F. R.; Sifter, L. L.; Strauss, M. G.

    1970-01-01

    Solid-state double-pulse generator for a high resolution semiconductor detector meets specific requirements for resolution /0.05 percent/, amplitude range /0.1-13 MeV/, and repetition rate /0.1-1000 pulses per second/. A tag pulse is generated in coincidence with each reference pulse.

  2. High Resolution Aerosol Modeling: Decadal Changes in Radiative Forcing

    SciTech Connect

    Bergmann, D J; Chuang, C C; Govindasamy, B; Cameron-Smith, P J; Rotman, D A

    2005-02-01

    The Atmospheric Science Division of LLNL has performed high-resolution calculations of direct sulfate forcing using a DOE-provided computer resource at NERSC. We integrated our global chemistry-aerosol model (IMPACT) with the LLNL high-resolution global climate model (horizontal resolution as high as 100 km) to examine the temporal evolution of sulfate forcing since 1950. We note that all previous assessments of sulfate forcing reported in IPCC (2001) were based on global models with coarse spatial resolutions ({approx} 300 km or even coarser). However, the short lifetime of aerosols ({approx} days) results in large spatial and temporal variations of radiative forcing by sulfate. As a result, global climate models with coarse resolutions do not accurately simulate sulfate forcing on regional scales. It requires much finer spatial resolutions in order to address the effects of regional anthropogenic SO{sub 2} emissions on the global atmosphere as well as the effects of long-range transport of sulfate aerosols on the regional climate forcing. By taking advantage of the tera-scale computer resources at NERSC, we simulated the historic direct sulfate forcing at much finer spatial resolutions than ever attempted before. Furthermore, we performed high-resolution chemistry simulations and saved monthly averaged oxidant fields, which will be used in subsequent simulations of sulfate aerosol formation and their radiative impact.

  3. High-Resolution Fluorometer for Mapping Microscale Phytoplankton Distributions

    PubMed Central

    Doubell, Mark J.; Seuront, Laurent; Seymour, Justin R.; Patten, Nicole L.; Mitchell, James G.

    2006-01-01

    A new high-resolution, in situ profiling fluorometer maps fluorescence distributions with a spatial resolution of 0.5 to 1.5 mm to a depth of 70 m in the open ocean. We report centimeter-scale patterns for phytoplankton distributions associated with gradients exhibiting 10- to 30-fold changes in fluorescence in contrasting marine ecosystems. PMID:16751572

  4. High-resolution fluorometer for mapping microscale phytoplankton distributions.

    PubMed

    Doubell, Mark J; Seuront, Laurent; Seymour, Justin R; Patten, Nicole L; Mitchell, James G

    2006-06-01

    A new high-resolution, in situ profiling fluorometer maps fluorescence distributions with a spatial resolution of 0.5 to 1.5 mm to a depth of 70 m in the open ocean. We report centimeter-scale patterns for phytoplankton distributions associated with gradients exhibiting 10- to 30-fold changes in fluorescence in contrasting marine ecosystems. PMID:16751572

  5. Demonstration of ultra high resolution soft x-ray tomography

    NASA Astrophysics Data System (ADS)

    Haddad, W. S.; McNulty, I.; Trebes, J. E.; Anderson, E. H.; Yang, L.; Brase, J. M.

    1995-05-01

    Ultra high resolution three dimensional images of a microscopic test object were made with soft x-rays using a scanning transmission x-ray microscope. The test object consisted of two different patterns of gold bars on silicon nitride windows which were separated by ˜ 5μm. Depth resolution comparable to the transverse resolution was achieved by recording nine 2-D images of the object at angles between -50 to +55 degrees with respect to the beam axis. The projections were then combined tomographically to form a 3-D image using an algebraic reconstruction technique (ART) algorithm. We observed a transverse resolution of ˜1000 Å. Artifacts in the reconstruction limited the overall depth resolution to ˜6000 Å, however some features were clearly reconstructed with a depth resolution of ˜1000 Å.

  6. Techniques in molecular spectroscopy: from broad bandwidth to high resolution

    NASA Astrophysics Data System (ADS)

    Cossel, Kevin C.

    This thesis presents a range of different experiments all seeking to extended the capabilities of molecular spectroscopy and enable new applications. The new technique of cavity-enhanced direct frequency comb spectroscopy (CE-DFCS) provides a unique combination of broad bandwidth, high resolution, and high sensitivity that can be useful for a wide range of applications. Previous demonstrations of CE-DFCS were confined to the visible or near-infrared and operated over a limited bandwidth: for many applications it is desirable to increase the spectral coverage and to extend to the mid-infrared where strong, fundamental vibrational modes of molecules occur. There are several key requirements for CE-DFCS: a frequency comb source that provides broad bandwidth and high resolution, an optical cavity for high sensitivity, and a detection system capable of multiplex detection of the comb spectrum transmitted through the cavity. We first discuss comb sources with emphasis on the coherence properties of spectral broadening in nonlinear fiber and the development of a high-power frequency comb source in the mid-infrared based on an optical-parametric oscillator (OPO). To take advantage of this new mid-infrared comb source for spectroscopy, we also discuss the development of a rapid-scan Fourier-transform spectrometer (FTS). We then discuss the first demonstration of CE-DFCS with spectrally broadened light from a highly nonlinear fiber with the application to measurements of impurities in semiconductor manufacturing gases. We also cover our efforts towards extending CE-DFCS to the mid-infrared using the mid-infrared OPO and FTS to measure ppb levels of various gases important for breath analysis and atmospheric chemistry and highlight some future applications of this system. In addition to the study of neutral molecules, broad-bandwidth and high-resolution spectra of molecular ions are useful for astrochemistry where many of the observed molecules are ionic, for studying

  7. High resolution remote sensing of water surface patterns

    NASA Astrophysics Data System (ADS)

    Woodget, A.; Visser, F.; Maddock, I.; Carbonneau, P.

    2012-12-01

    The assessment of in-stream habitat availability within fluvial environments in the UK traditionally includes the mapping of patterns which appear on the surface of the water, known as 'surface flow types' (SFTs). The UK's River Habitat Survey identifies ten key SFTs, including categories such as rippled flow, upwelling, broken standing waves and smooth flow. SFTs result from the interaction between the underlying channel morphology, water depth and velocity and reflect the local flow hydraulics. It has been shown that SFTs can be both biologically and hydraulically distinct. SFT mapping is usually conducted from the river banks where estimates of spatial coverage are made by eye. This approach is affected by user subjectivity and inaccuracies in the spatial extent of mapped units. Remote sensing and specifically the recent developments in unmanned aerial systems (UAS) may now offer an alternative approach for SFT mapping, with the capability for rapid and repeatable collection of very high resolution imagery from low altitudes, under bespoke flight conditions. This PhD research is aimed at investigating the mapping of SFTs using high resolution optical imagery (less than 10cm) collected from a helicopter-based UAS flown at low altitudes (less than 100m). This paper presents the initial findings from a series of structured experiments on the River Arrow, a small lowland river in Warwickshire, UK. These experiments investigate the potential for mapping SFTs from still and video imagery of different spatial resolutions collected at different flying altitudes and from different viewing angles (i.e. vertical and oblique). Imagery is processed using 3D mosaicking software to create orthophotos and digital elevation models (DEM). The types of image analysis which are tested include a simple, manual visual assessment undertaken in a GIS environment, based on the high resolution optical imagery. In addition, an object-based image analysis approach which makes use of the

  8. Applications of high resolution inverse Raman spectroscopy

    SciTech Connect

    Owyoung, A.; Esherick, P.

    1980-01-01

    The use of high-power, narrow-band lasers has significantly improved the resolving power and sensitivity of inverse Raman spectroscopy of gases. In this paper we shall describe this technique, illustrate its capabilities by showing some Q-branch spectra of heavy spherical tops, and survey some possible future applications.

  9. III-Nitride full-scale high-resolution microdisplays

    NASA Astrophysics Data System (ADS)

    Day, Jacob; Li, J.; Lie, D. Y. C.; Bradford, Charles; Lin, J. Y.; Jiang, H. X.

    2011-07-01

    We report the realization and properties of a high-resolution solid-state self-emissive microdisplay based on III-nitride semiconductor micro-size light emitting diodes (µLEDs) capable of delivering video graphics images. The luminance level of III-nitride microdisplays is several orders of magnitude higher than those of liquid crystal and organic-LED displays. The pixel emission intensity was almost constant over an operational temperature range from 100 to -100 °C. The outstanding performance is a direct attribute of III-nitride semiconductors. An energy efficient active drive scheme is accomplished by hybrid integration between µLED arrays and Si CMOS (complementary metal-oxide-semiconductor) active matrix integrated circuits. These integrated devices could play important roles in emerging fields such as biophotonics and optogenetics, as well as ultra-portable products such as next generation pico-projectors.

  10. Temporomandibular joints: high-resolution computed tomographic evaluation

    SciTech Connect

    Thompson, J.R.; Christiansen, E.; Hasso, A.N.; Hinshaw, D.B. Jr.

    1984-01-01

    High-resolution computed tomography of the temporomandibular joint (TMJ) was performed in 43 patients. Exquisite detail of the face, skull base, and TMJs was obtained with CT using soft tissue and bone algorithms, narrow collimation, and multiplanar images. In 10 patients clinically suspected of joint derangement, CT results were in close agreement with surgical findings and arthrography in 13/15 joints. CT showed indirect signs of disc dislocation, and the dislocated disc itself in 81% of affected joints. In two patients, arthrography with CT proved to be more helpful than conventional arthrography alone. CT without intra-articular contrast material provided information not appreciated on conventional radiogaphs in 28 patients (65%) and was particularly helpful in evaluating patients with disc pathosis and trauma. Early experience with CT of the TMJ shows that it is an excellent method of evaluation at acceptable radiation exposure levels that adds essential information not seen on standard radiographs.

  11. Proteogenomic Analysis of Mycobacterium smegmatis Using High Resolution Mass Spectrometry

    PubMed Central

    Potgieter, Matthys G.; Nakedi, Kehilwe C.; Ambler, Jon M.; Nel, Andrew J. M.; Garnett, Shaun; Soares, Nelson C.; Mulder, Nicola; Blackburn, Jonathan M.

    2016-01-01

    Biochemical evidence is vital for accurate genome annotation. The integration of experimental data collected at the proteome level using high resolution mass spectrometry allows for improvements in genome annotation by providing evidence for novel gene models, while validating or modifying others. Here, we report the results of a proteogenomic analysis of a reference strain of Mycobacterium smegmatis (mc2155), a fast growing model organism for the pathogenic Mycobacterium tuberculosis—the causative agent for Tuberculosis. By integrating high throughput LC/MS/MS proteomic data with genomic six frame translation and ab initio gene prediction databases, a total of 2887 ORFs were identified, including 2810 ORFs annotated to a Reference protein, and 63 ORFs not previously annotated to a Reference protein. Further, the translational start site (TSS) was validated for 558 Reference proteome gene models, while upstream translational evidence was identified for 81. In addition, N-terminus derived peptide identifications allowed for downstream TSS modification of a further 24 gene models. We validated the existence of six previously described interrupted coding sequences at the peptide level, and provide evidence for four novel frameshift positions. Analysis of peptide posterior error probability (PEP) scores indicates high-confidence novel peptide identifications and shows that the genome of M. smegmatis mc2155 is not yet fully annotated. Data are available via ProteomeXchange with identifier PXD003500. PMID:27092112

  12. Super high-resolution mesoscale weather prediction

    NASA Astrophysics Data System (ADS)

    Saito, K.; Tsuyuki, T.; Seko, H.; Kimura, F.; Tokioka, T.; Kuroda, T.; Duc, L.; Ito, K.; Oizumi, T.; Chen, G.; Ito, J.; the Spire Field 3 Mesoscale Nwp Group

    2013-08-01

    A five-year research project of high performance regional numerical weather prediction is underway as one of the five research fields of the Strategic Programs for Innovative Research (SPIRE). The ultimate goal of the project is to demonstrate feasibility of precise prediction of severe weather phenomena using the K-computer. Three sub-themes of the project are shown with achievements at the present and developments in the near future.

  13. Special issue on high-resolution optical imaging

    NASA Astrophysics Data System (ADS)

    Smith, Peter J. S.; Davis, Ilan; Galbraith, Catherine G.; Stemmer, Andreas

    2013-09-01

    The pace of development in the field of advanced microscopy is truly breath-taking, and is leading to major breakthroughs in our understanding of molecular machines and cell function. This special issue of Journal of Optics draws attention to a number of interesting approaches, ranging from fluorescence and imaging of unlabelled cells, to computational methods, all of which are describing the ever increasing detail of the dynamic behaviour of molecules in the living cell. This is a field which traditionally, and currently, demonstrates a marvellous interplay between the disciplines of physics, chemistry and biology, where apparent boundaries to resolution dissolve and living cells are viewed in ever more clarity. It is fertile ground for those interested in optics and non-conventional imaging to contribute high-impact outputs in the fields of cell biology and biomedicine. The series of articles presented here has been selected to demonstrate this interdisciplinarity and to encourage all those with a background in the physical sciences to 'dip their toes' into the exciting and dynamic discoveries surrounding cell function. Although single molecule super-resolution microscopy is commercially available, specimen preparation and interpretation of single molecule data remain a major challenge for scientists wanting to adopt the techniques. The paper by Allen and Davidson [1] provides a much needed detailed introduction to the practical aspects of stochastic optical reconstruction microscopy, including sample preparation, image acquisition and image analysis, as well as a brief description of the different variants of single molecule localization microscopy. Since super-resolution microscopy is no longer restricted to three-dimensional imaging of fixed samples, the review by Fiolka [2] is a timely introduction to techniques that have been successfully applied to four-dimensional live cell super-resolution microscopy. The combination of multiple high-resolution techniques

  14. High resolution survey for topographic surveying

    NASA Astrophysics Data System (ADS)

    Luh, L. C.; Setan, H.; Majid, Z.; Chong, A. K.; Tan, Z.

    2014-02-01

    In this decade, terrestrial laser scanner (TLS) is getting popular in many fields such as reconstruction, monitoring, surveying, as-built of facilities, archaeology, and topographic surveying. This is due the high speed in data collection which is about 50,000 to 1,000,000 three-dimensional (3D) points per second at high accuracy. The main advantage of 3D representation for the data is that it is more approximate to the real world. Therefore, the aim of this paper is to show the use of High-Definition Surveying (HDS), also known as 3D laser scanning for topographic survey. This research investigates the effectiveness of using terrestrial laser scanning system for topographic survey by carrying out field test in Universiti Teknologi Malaysia (UTM), Skudai, Johor. The 3D laser scanner used in this study is a Leica ScanStation C10. Data acquisition was carried out by applying the traversing method. In this study, the result for the topographic survey is under 1st class survey. At the completion of this study, a standard of procedure was proposed for topographic data acquisition using laser scanning systems. This proposed procedure serves as a guideline for users who wish to utilize laser scanning system in topographic survey fully.

  15. Strategies for Interpreting High Resolution Coherent Multidimensional Spectra

    NASA Astrophysics Data System (ADS)

    Wells, Thresa A.; House, Zuri R.; Chen, Peter C.; Strangfeld, Benjamin R.

    2013-06-01

    The electronic spectra of certain molecules can be very complex and consist of a high density of peaks. The high density of peaks results in severe spectral congestion, making conventional data analysis techniques extremely difficult to use. One solution to this problem is to use high resolution coherent 2D spectroscopy (HRC2DS), which can improve resolution and sort peaks into recognizable clusters. This technique requires new data analysis techniques to accurately assign peaks. Even though HRC2DS can improve spectral resolution, some regions of the spectra may still remain congested. The ability to solve this problem using even higher dimensional techniques (e.g., high resolution coherent 3D spectroscopy) with 3D pattern recognition and data analysis techniques will be discussed.

  16. High Resolution Imaging of Circumstellar Disks at Millimeter Wavelengths

    NASA Technical Reports Server (NTRS)

    Wilner, David J.

    2004-01-01

    We summarize progress on our program to use high angular resolution imaging of thermal dust continuum emission at millimeter and submillimeter wavelengths to probe the structure of protoplanetary disks and debris disks around nearby stars.

  17. Methodology of high-resolution photography for mural condition database

    NASA Astrophysics Data System (ADS)

    Higuchi, R.; Suzuki, T.; Shibata, M.; Taniguchi, Y.

    2015-08-01

    Digital documentation is one of the most useful techniques to record the condition of cultural heritage. Recently, high-resolution images become increasingly useful because it is possible to show general views of mural paintings and also detailed mural conditions in a single image. As mural paintings are damaged by environmental stresses, it is necessary to record the details of painting condition on high-resolution base maps. Unfortunately, the cost of high-resolution photography and the difficulty of operating its instruments and software have commonly been an impediment for researchers and conservators. However, the recent development of graphic software makes its operation simpler and less expensive. In this paper, we suggest a new approach to make digital heritage inventories without special instruments, based on our recent our research project in Üzümlü church in Cappadocia, Turkey. This method enables us to achieve a high-resolution image database with low costs, short time, and limited human resources.

  18. The Advanced X-ray Astrophysics Facility high resolution camera

    NASA Technical Reports Server (NTRS)

    Murray, Stephen S.; Chappell, Jon H.

    1986-01-01

    The HRC (High Resolution Camera) is a photon counting instrument to be flown on the Advanced X-Ray Astrophysics Facility (AXAF). It is a large field of view, high angular resolution, detector for the X-ray telescope. The HRC consists of a CsI coated microchannel plate (MCP) acting as a soft X-ray photocathode, followed by a second MCP for high electronic gain. The MCPs are readout by a crossed grid of resistively coupled wires to provide high spatial resolution along with timing and pulse height data. The instrument will be used in two modes, as a direct imaging detector with a limiting sensitivity of 10 to the -15th ergs/sq cm sec in a 10 to the 5th second exposure, and as a readout for an objective transmission grating providing spectral resolution of several hundreds to thousands.

  19. A compact, light weight, high resolution electron monochromator

    NASA Astrophysics Data System (ADS)

    Goembel, L.; Doering, J. P.

    1995-06-01

    A high resolution electron monochromator that incorporates Vespel polyimide plastic in its construction is described. A great saving in bulk can be realized by mounting the electron optical elements in Vespel tubes rather than mounting them by traditional means.

  20. High Resolution CryoFESEM of Microbial Surfaces

    NASA Astrophysics Data System (ADS)

    Erlandsen, Stanley; Lei, Ming; Martin-Lacave, Ines; Dunny, Gary; Wells, Carol

    2003-08-01

    The outer surfaces of three microorganisms, Giardia lamblia, Enterococcus faecalis, and Proteus mirabilis, were investigated by cryo-immobilization followed by sublimation of extracellular ice and cryocoating with either Pt alone or Pt plus carbon. Cryocoated samples were examined at [minus sign]125°C in either an in-lens field emission SEM or a below-the-lens field emission SEM. Cryocoating with Pt alone was sufficient for low magnification observation, but attempts to do high-resolution imaging resulted in radiolysis and cracking of the specimen surface. Double coating with Pt and carbon, in combination with high resolution backscatter electron detectors, enabled high-resolution imaging of the glycocalyx of bacteria, revealing a sponge-like network over the surface. High resolution examination of bacterial flagella also revealed a periodic substructure. Common artifacts included radiolysis leading to “cracking” of the surface, and insufficient deposition of Pt resulting in the absence of detectable surface topography.

  1. Update on High-Resolution Geodetically Controlled LROC Polar Mosaics

    NASA Astrophysics Data System (ADS)

    Archinal, B.; Lee, E.; Weller, L.; Richie, J.; Edmundson, K.; Laura, J.; Robinson, M.; Speyerer, E.; Boyd, A.; Bowman-Cisneros, E.; Wagner, R.; Nefian, A.

    2015-10-01

    We describe progress on high-resolution (1 m/pixel) geodetically controlled LROC mosaics of the lunar poles, which can be used for locating illumination resources (for solar power or cold traps) or landing site and surface operations planning.

  2. High resolution difference schemes for compressible gas dynamics

    SciTech Connect

    Woodward, P.; Colella, P.

    1980-07-30

    The advantages and disadvantages of four new high-resolution difference schemes, namely the von Neumann-Richtmyer, Godunovs, MUSCL and Glimms, for mathematically representing physical conditions in compressible gas flows are compared. (LCL)

  3. Mapping of Settlements in High Resolution Satellite Imagery using High Performance Computing

    SciTech Connect

    Cheriydat, Anil; Bright, Eddie A; Bhaduri, Budhendra L; Potere, David T

    2007-01-01

    Classifying urban land cover from high-resolution satellite imagery is challenging, and those challenges are compounded when the imagery databases are very large. Accurate land cover data is a crucial component of the population distribution modeling efforts of the Oak Ridge National Laboratory's (ORNL) LandScan Program. Currently, LandScan Program imagery analysts manually interpret high-resolution (1-5 meter) imagery to augment existing satellite-derived medium (30m) and coarse (1km) resolution land cover datasets. At LandScan, the high-resolution image archives that require interpretation are on the order of terabytes. The goal of this research is to automate urban land cover mapping utilizing ORNL's high performance computing capabilities. Our algorithm employs gray-level and local edge-pattern co-occurrence matrices to generate texture and edge patterns. Areas of urban land cover correlate with statistical features derived from these texture and edge patterns. We have parallelized our algorithms for implementation on a 64-node system using a single instruction multiple data programming model (SIMD) with Message Passing Interface (MPI) as the communication mode. Our parallel-configured classifier performs 30-40 times faster than stand-alone alternatives. When compared with manually interpreted IKONOS imagery, the classifier achieves a 91% overall accuracy. These early results are promising, pointing towards future large-scale classification of urban areas.

  4. Crevasse-splay sedimentation processes revealed through high resolution modelling

    NASA Astrophysics Data System (ADS)

    Hackney, Christopher; Darby, Stephen; Parsons, Daniel; Leyland, Julian; Aalto, Rolf; Nicholas, Andrew; Best, Jim

    2015-04-01

    During rapid rise flood events, crevasse-splay complexes are a dominant conduit through which sediment and water are passed from the main channel onto the floodplain, particularly for large rivers. These crevasse-splay systems are, therefore, key in controlling rates of floodplain sedimentation, as well as conditioning the location of avulsions. Despite recent advances in our capabilities to model the development and evolution of these systems, our understanding of the passage, storage and reworking of water and sediment across them remains relatively poor. A key limitation concerns the point that, since floodplain topography is a first-order control on the hydrodynamics of crevasse-splays, publicly available topographic data sets (e.g. SRTM) are currently unable to resolve key processes at the necessary spatial resolution. Here we employ Structure-from-Motion (SfM) on low-level aerial photography to obtain high-resolution (3m grid cell) georectified topographic data (horizontal error = 0.02 m; vertical error = 0.5 m) for a series of three representative crevasse-splay complexes located along the Mekong River, Cambodia. We use the coupled hydrodynamic and morphodynamic model, Delft-3D to simulate sedimentation patterns for a series of flood events. We model floodplain deposition and erosion and validate simulated spatial and temporal variations against observed patterns. We show how the spatial and temporal patterns of floodplain development via crevasse-splays are conditioned by key hydrological characteristics.

  5. High-Resolution Optical Tweezers for Single-Molecule Manipulation

    PubMed Central

    Zhang, Xinming; Ma, Lu; Zhang, Yongli

    2013-01-01

    Forces hold everything together and determine its structure and dynamics. In particular, tiny forces of 1-100 piconewtons govern the structures and dynamics of biomacromolecules. These forces enable folding, assembly, conformational fluctuations, or directional movements of biomacromolecules over sub-nanometer to micron distances. Optical tweezers have become a revolutionary tool to probe the forces, structures, and dynamics associated with biomacromolecules at a single-molecule level with unprecedented resolution. In this review, we introduce the basic principles of optical tweezers and their latest applications in studies of protein folding and molecular motors. We describe the folding dynamics of two strong coiled coil proteins, the GCN4-derived protein pIL and the SNARE complex. Both complexes show multiple folding intermediates and pathways. ATP-dependent chromatin remodeling complexes translocate DNA to remodel chromatin structures. The detailed DNA translocation properties of such molecular motors have recently been characterized by optical tweezers, which are reviewed here. Finally, several future developments and applications of optical tweezers are discussed. These past and future applications demonstrate the unique advantages of high-resolution optical tweezers in quantitatively characterizing complex multi-scale dynamics of biomacromolecules. PMID:24058311

  6. High resolution spectroscopic study of BeΛ10

    DOE PAGESBeta

    Gogami, T.; Chen, C.; Kawama, D.; Achenbach, P.; Ahmidouch, A.; Albayrak, I.; Androic, D.; Asaturyan, A.; Asaturyan, R.; Ates, O.; et al

    2016-03-10

    Spectroscopy of amore » $$^{10}_{\\Lambda}$$Be hypernucleus was carried out at JLab Hall C using the $$(e,e^{\\prime}K^{+})$$ reaction. A new magnetic spectrometer system (SPL+HES+HKS), specifically designed for high resolution hypernuclear spectroscopy, was used to obtain an energy spectrum with a resolution of 0.78 MeV (FWHM). The well-calibrated spectrometer system of the present experiment using the $$p(e,e^{\\prime}K^{+})\\Lambda,\\Sigma^{0}$$ reactions allowed us to determine the energy levels, and the binding energy of the ground state peak (mixture of 1$$^{-}$$ and 2$$^{-}$$ states) was obtained to be B$$_{\\Lambda}$$=8.55$$\\pm$$0.07(stat.)$$\\pm$$0.11(sys.) MeV. Furthermore, the result indicates that the ground state energy is shallower than that of an emulsion study by about 0.5 MeV which provides valuable experimental information on charge symmetry breaking effect in the $$\\Lambda N$$ interaction.« less

  7. Impact of High Resolution SST Data on Regional Weather Forecasts

    NASA Technical Reports Server (NTRS)

    Jedlovec, Gary J.; Case, Jonathon; LaFontaine, Frank; Vazquez, Jorge; Mattocks, Craig

    2010-01-01

    Past studies have shown that the use of coarse resolution SST products such as from the real-time global (RTG) SST analysis[1] or other coarse resolution once-a-day products do not properly portray the diurnal variability of fluxes of heat and moisture from the ocean that drive the formation of low level clouds and precipitation over the ocean. For example, the use of high resolution MODIS SST composite [2] to initialize the Advanced Research Weather Research and Forecast (WRF) (ARW) [3] has been shown to improve the prediction of sensible weather parameters in coastal regions [4][5}. In an extend study, [6] compared the MODIS SST composite product to the RTG SST analysis and evaluated forecast differences for a 6 month period from March through August 2007 over the Florida coastal regions. In a comparison to buoy data, they found that that the MODIS SST composites reduced the bias and standard deviation over that of the RTG data. These improvements led to significant changes in the initial and forecasted heat fluxes and the resulting surface temperature fields, wind patterns, and cloud distributions. They also showed that the MODIS composite SST product, produced for the Terra and Aqua satellite overpass times, captured a component of the diurnal cycle in SSTs not represented in the RTG or other one-a-day SST analyses. Failure to properly incorporate these effects in the WRF initialization cycle led to temperature biases in the resulting short term forecasts. The forecast impact was limited in some situations however, due to composite product inaccuracies brought about by data latency during periods of long-term cloud cover. This paper focuses on the forecast impact of an enhanced MODIS/AMSR-E composite SST product designed to reduce inaccuracies due data latency in the MODIS only composite product.

  8. PANGU: A High Resolution Gamma-Ray Space Telescope

    NASA Astrophysics Data System (ADS)

    Su, Meng

    2014-08-01

    We propose a high angular resolution telescope dedicated to the sub-GeV gamma-ray astronomy as a candidate for the CAS-ESA joint small mission. This mission, called PANGU (PAir-productioN Gamma-ray Unit), will open up a unique window of electromagnetic spectrum that has never been explored with great precision. A wide range of topics of both astronomy and fundamental physics can be attacked with a telescope that has an angular resolution about one order of magnitude better than the currently operating Fermi Gamma-ray Space Telescope (Fermi) in the sub-GeV range, covering galactic and extragalactic cosmic-ray physics, extreme physics of a variety of extended (e.g. supernova remnants, galaxies, galaxy clusters) and compact (e.g. black holes, pulsars, gamma-ray bursts) objects, solar and terrestrial gamma-ray phenomena, and searching for Dark Matter (DM) decay and/or annihilation signature etc. The unprecedented resolution can be achieved with a pair-production telescope that, instead of the high-Z converter commonly used, relies on a large number of thin active tracking layers to increase the photon conversion probability, and to precisely reconstruct the pair-produced electron and positron tracks. Scintillating fibers or thin silicon micro-strip detectors are suitable technology for such a tracker. The energy measurement is achieved by measuring the momentum of the electrons and positrons through a magnetic field. The innovated spectrometer approach provides superior photon conversion identification and photon pointing resolution, and is particular suitable in the sub-GeV range, where the opening angle between the electron and positron is relatively large. The level of tracking precision makes it possible to measure the polarization of gamma rays, which would open up a new frontier in gamma-ray astronomy. The sub-GeV full sky survey by PANGU would provides crucial link with GeV to TeV maps from current/future missions including Fermi, DAMPE, HERD, and CTA.

  9. High resolution simulation of the South Asian monsoon using a variable resolution global climate model

    NASA Astrophysics Data System (ADS)

    P Sabin, T.; Krishnan, R.; Ghattas, Josefine; Denvil, Sebastien; Dufresne, Jean-Louis; Hourdin, Frederic; Pascal, Terray

    2013-07-01

    This study examines the feasibility of using a variable resolution global general circulation model (GCM), with telescopic zooming and enhanced resolution (~35 km) over South Asia, to better understand regional aspects of the South Asian monsoon rainfall distribution and the interactions between monsoon circulation and precipitation. For this purpose, two sets of ten member realizations are produced with and without zooming using the LMDZ (Laboratoire Meteorologie Dynamique and Z stands for zoom) GCM. The simulations without zoom correspond to a uniform 1° × 1° grid with the same total number of grid points as in the zoom version. So the grid of the zoomed simulations is finer inside the region of interest but coarser outside. The use of these finer and coarser resolution ensemble members allows us to examine the impact of resolution on the overall quality of the simulated regional monsoon fields. It is found that the monsoon simulation with high-resolution zooming greatly improves the representation of the southwesterly monsoon flow and the heavy precipitation along the narrow orography of the Western Ghats, the northeastern mountain slopes and northern Bay of Bengal (BOB). A realistic Monsoon Trough (MT) is also noticed in the zoomed simulation, together with remarkable improvements in representing the associated precipitation and circulation features, as well as the large-scale organization of meso-scale convective systems over the MT region. Additionally, a more reasonable simulation of the monsoon synoptic disturbances (lows and disturbances) along the MT is noted in the high-resolution zoomed simulation. On the other hand, the no-zoom version has limitations in capturing the depressions and their movement, so that the MT zone is relatively dry in this case. Overall, the results from this work demonstrate the usefulness of the high-resolution variable resolution LMDZ model in realistically capturing the interactions among the monsoon large-scale dynamics

  10. Microbeam X-Ray Standing Wave and High Resolution Diffraction

    SciTech Connect

    Kazimirov, A.; Bilderback, D.H.; Huang, R.; Sirenko, A.

    2004-05-12

    Post-focusing collimating optics are introduced as a tool to condition X-ray microbeams for the use in high-resolution X-ray diffraction and scattering techniques. As an example, a one-bounce imaging capillary and miniature Si(004) channel-cut crystal were used to produce a microbeam with 10 {mu}m size and an ultimate angular resolution of 2.5 arc sec. This beam was used to measure the strain in semiconductor microstructures by using X-ray high resolution diffraction and standing wave techniques to {delta}d/d < 5x10-4.

  11. AVHRR/1-FM Advanced Very High Resolution Radiometer

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The advanced very high resolution radiometer is discussed. The program covers design, construction, and test of a breadboard model, engineering model, protoflight model, mechanical/structural model, and a life test model. Special bench test and calibration equipment was developed for use on the program. The flight model program objectives were to fabricate, assemble and test four of the advanced very high resolution radiometers along with a bench cooler and collimator.

  12. High energy resolution, high angular acceptance crystal monochromator

    DOEpatents

    Alp, Ercan E.; Mooney, Timothy M.; Toellner, Thomas

    1996-06-04

    A 4-bounce dispersive crystal monochromator reduces the bandpass of synchrotron radiation to a 10-50 meV range without sacrificing angular acceptance. The monochromator includes the combination of an asymmetrical channel-cut single crystal of lower order reflection and a symmetrical channel-cut single crystal of higher order reflection in a nested geometric configuration. In the disclosed embodiment, a highly asymmetrically cut (.alpha.=20) outer silicon crystal (4 2 2) with low order reflection is combined with a symmetrically cut inner silicon crystal (10 6 4) with high order reflection to condition a hard x-ray component (5-30 keV) of synchrotron radiation down to the .mu.eV-neV level. Each of the crystals is coupled to the combination of a positioning inchworm and angle encoder via a respective rotation stage for accurate relative positioning of the crystals and precise energy tuning of the monochromator.

  13. High energy resolution, high angular acceptance crystal monochromator

    DOEpatents

    Alp, E.E.; Mooney, T.M.; Toellner, T.

    1996-06-04

    A 4-bounce dispersive crystal monochromator reduces the bandpass of synchrotron radiation to a 10-50 meV range without sacrificing angular acceptance. The monochromator includes the combination of an asymmetrical channel-cut single crystal of lower order reflection and a symmetrical channel-cut single crystal of higher order reflection in a nested geometric configuration. In the disclosed embodiment, a highly asymmetrically cut ({alpha}=20) outer silicon crystal (4 2 2) with low order reflection is combined with a symmetrically cut inner silicon crystal (10 6 4) with high order reflection to condition a hard x-ray component (5--30 keV) of synchrotron radiation down to the {micro}eV-neV level. Each of the crystals is coupled to the combination of a positioning inchworm and angle encoder via a respective rotation stage for accurate relative positioning of the crystals and precise energy tuning of the monochromator. 7 figs.

  14. Phase contrast in high resolution electron microscopy

    DOEpatents

    Rose, H.H.

    1975-09-23

    This patent relates to a device for developing a phase contrast signal for a scanning transmission electron microscope. The lens system of the microscope is operated in a condition of defocus so that predictable alternate concentric regions of high and low electron density exist in the cone of illumination. Two phase detectors are placed beneath the object inside the cone of illumination, with the first detector having the form of a zone plate, each of its rings covering alternate regions of either higher or lower electron density. The second detector is so configured that it covers the regions of electron density not covered by the first detector. Each detector measures the number of electrons incident thereon and the signal developed by the first detector is subtracted from the signal developed by the record detector to provide a phase contrast signal. (auth)

  15. High-resolution tunnelling spectroscopy of a graphene quartet.

    PubMed

    Song, Young Jae; Otte, Alexander F; Kuk, Young; Hu, Yike; Torrance, David B; First, Phillip N; de Heer, Walt A; Min, Hongki; Adam, Shaffique; Stiles, Mark D; MacDonald, Allan H; Stroscio, Joseph A

    2010-09-01

    Electrons in a single sheet of graphene behave quite differently from those in traditional two-dimensional electron systems. Like massless relativistic particles, they have linear dispersion and chiral eigenstates. Furthermore, two sets of electrons centred at different points in reciprocal space ('valleys') have this dispersion, giving rise to valley degeneracy. The symmetry between valleys, together with spin symmetry, leads to a fourfold quartet degeneracy of the Landau levels, observed as peaks in the density of states produced by an applied magnetic field. Recent electron transport measurements have observed the lifting of the fourfold degeneracy in very large applied magnetic fields, separating the quartet into integer and, more recently, fractional levels. The exact nature of the broken-symmetry states that form within the Landau levels and lift these degeneracies is unclear at present and is a topic of intense theoretical debate. Here we study the detailed features of the four quantum states that make up a degenerate graphene Landau level. We use high-resolution scanning tunnelling spectroscopy at temperatures as low as 10 mK in an applied magnetic field to study the top layer of multilayer epitaxial graphene. When the Fermi level lies inside the fourfold Landau manifold, significant electron correlation effects result in an enhanced valley splitting for even filling factors, and an enhanced electron spin splitting for odd filling factors. Most unexpectedly, we observe states with Landau level filling factors of 7/2, 9/2 and 11/2, suggestive of new many-body states in graphene. PMID:20829790

  16. Optical Histology: High-Resolution Visualization of Tissue Microvasculature

    NASA Astrophysics Data System (ADS)

    Moy, Austin Jing-Ming

    Mammalian tissue requires the delivery of nutrients, growth factors, and the exchange of oxygen and carbon dioxide gases to maintain normal function. These elements are delivered by the blood, which travels through the connected network of blood vessels, known as the vascular system. The vascular system consists of large feeder blood vessels (arteries and veins) that are connected to the small blood vessels (arterioles and venules), which in turn are connected to the capillaries that are directly connected to the tissue and facilitate gas exchange and nutrient delivery. These small blood vessels and capillaries make up an intricate but organized network of blood vessels that exist in all mammalian tissues known as the microvasculature and are very important in maintaining the health and proper function of mammalian tissue. Due to the importance of the microvasculature in tissue survival, disruption of the microvasculature typically leads to tissue dysfunction and tissue death. The most prevalent method to study the microvasculature is visualization. Immunohistochemistry (IHC) is the gold-standard method to visualize tissue microvasculature. IHC is very well-suited for highly detailed interrogation of the tissue microvasculature at the cellular level but is unwieldy and impractical for wide-field visualization of the tissue microvasculature. The objective my dissertation research was to develop a method to enable wide-field visualization of the microvasculature, while still retaining the high-resolution afforded by optical microscopy. My efforts led to the development of a technique dubbed "optical histology" that combines chemical and optical methods to enable high-resolution visualization of the microvasculature. The development of the technique first involved preliminary studies to quantify optical property changes in optically cleared tissues, followed by development and demonstration of the methodology. Using optical histology, I successfully obtained high

  17. High spectral resolution image of Barnacle Bill

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The rover Sojourner's first target for measurement by the Alpha-Proton-Xray Spectrometer (APXS) was the rock named Barnacle Bill, located close to the ramp down which the rover made its egress from the lander. The full spectral capability of the Imager for Mars Pathfinder (IMP), consisting of 13 wavelength filters, was used to characterize the rock's surface. The measured area is relatively dark, and is shown in blue. Nearby on the rock surface, soil material is trapped in pits (shown in red).

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. The Imager for Mars Pathfinder (IMP) was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator. JPL is an operating division of the California Institute of Technology (Caltech).

  18. High Resolution Infrared Spectra of Triacetylene

    NASA Astrophysics Data System (ADS)

    Doney, Kirstin D.; Zhao, Dongfeng; Linnartz, Harold

    2015-06-01

    Triacetylene, HC6H, is the longest poly-acetylene chain found in space, and is believed to be involved in the formation of longer chain molecules and polycyclic aromatic hydrocarbons (PAHs). However, abundances are expected to be low, and observational confirmation requires knowledge of the gas-phase spectra, which up to now has been incomplete with only the weak, low lying bending modes being known. We present new infrared (IR) spectra in the C-H stretch region obtained using ultra-sensitive and highly precise IR continuous wave cavity ring-down spectroscopy (cw-CRDS), combined with supersonic plasma expansions The talk reviews the accurate determination of the rotational constants of the asymmetric fundamental mode, νb{5}, including discussion on the perturber state, and associated hot bands. The determined molecular parameters are accurate enough to aid astronomical searches with such facilities as ALMA (Atacama Large Millimeter Array) or the upcoming JWST (James Webb Space Telecscope), which can now probe even trace molecules (abundances of ˜ 10-6 - 10-10 with respect to H2). D. Zhao, J. Guss, A. Walsh, H. Linnartz, Chem. Phys. Lett., 565, 132 (2013) K.D. Doney, D. Zhao, H. Linnartz, in preparation

  19. High resolution amorphous silicon radiation detectors

    DOEpatents

    Street, R.A.; Kaplan, S.N.; Perez-Mendez, V.

    1992-05-26

    A radiation detector employing amorphous Si:H cells in an array with each detector cell having at least three contiguous layers (n-type, intrinsic, p-type), positioned between two electrodes to which a bias voltage is applied. An energy conversion layer atop the silicon cells intercepts incident radiation and converts radiation energy to light energy of a wavelength to which the silicon cells are responsive. A read-out device, positioned proximate to each detector element in an array allows each such element to be interrogated independently to determine whether radiation has been detected in that cell. The energy conversion material may be a layer of luminescent material having a columnar structure. In one embodiment a column of luminescent material detects the passage therethrough of radiation to be detected and directs a light beam signal to an adjacent a-Si:H film so that detection may be confined to one or more such cells in the array. One or both electrodes may have a comb structure, and the teeth of each electrode comb may be interdigitated for capacitance reduction. The amorphous Si:H film may be replaced by an amorphous Si:Ge:H film in which up to 40 percent of the amorphous material is Ge. Two dimensional arrays may be used in X-ray imaging, CT scanning, crystallography, high energy physics beam tracking, nuclear medicine cameras and autoradiography. 18 figs.

  20. High resolution amorphous silicon radiation detectors

    DOEpatents

    Street, Robert A.; Kaplan, Selig N.; Perez-Mendez, Victor

    1992-01-01

    A radiation detector employing amorphous Si:H cells in an array with each detector cell having at least three contiguous layers (n type, intrinsic, p type), positioned between two electrodes to which a bias voltage is applied. An energy conversion layer atop the silicon cells intercepts incident radiation and converts radiation energy to light energy of a wavelength to which the silicon cells are responsive. A read-out device, positioned proximate to each detector element in an array allows each such element to be interrogated independently to determine whether radiation has been detected in that cell. The energy conversion material may be a layer of luminescent material having a columnar structure. In one embodiment a column of luminescent material detects the passage therethrough of radiation to be detected and directs a light beam signal to an adjacent a-Si:H film so that detection may be confined to one or more such cells in the array. One or both electrodes may have a comb structure, and the teeth of each electrode comb may be interdigitated for capacitance reduction. The amorphous Si:H film may be replaced by an amorphous Si:Ge:H film in which up to 40 percent of the amorphous material is Ge. Two dimensional arrays may be used in X-ray imaging, CT scanning, crystallography, high energy physics beam tracking, nuclear medicine cameras and autoradiography.

  1. Space instrument performance traceability for high resolution satellite systems

    NASA Astrophysics Data System (ADS)

    Eckardt, A.; Börner, A.; Jahn, H.; Reulke, R.

    2008-08-01

    Technology changes in detector development and the significant improvement of manufacturing accuracy in combination with the permanent engineering research influences the spaceborne sensor systems, which are focused on Earth observation and remote sensing. Developments in focal plane technology, e.g. the combination of large TDI lines, intelligent synchronisation control, fast readable sensors and new focal plane and telescope concepts are the key developments for new remote sensing instruments. This class of instruments disposes of high spatial and radiometric resolution for the generation of data products for mapping and 3D GIS VR applications. Systemic approaches are essential for the design of complex sensor systems based on dedicated tasks. The system-theoretical description of the instrument inside and a simulated environment is the basic approach for the optimisation process of the optical, mechanical and electrical designs and assembly. Single modules and the entire system have to be calibrated and verified. The traceability of the performance-related parameters from the single sensor up to the flight readiness of the instrument forms the main focus inside such complex systems. In the future it will also be possible to prove the sensor performance on wafer level before assembly. This paper gives an overview about current technologies for performance measurements on sensor, focal plane assembly (FPA) and instrument level without the optical performance of the telescope. The paper proposes also a technology, which can be used for sensor performance measurements on wafer level.

  2. High resolution single particle refinement in EMAN2.1.

    PubMed

    Bell, James M; Chen, Muyuan; Baldwin, Philip R; Ludtke, Steven J

    2016-05-01

    EMAN2.1 is a complete image processing suite for quantitative analysis of grayscale images, with a primary focus on transmission electron microscopy, with complete workflows for performing high resolution single particle reconstruction, 2-D and 3-D heterogeneity analysis, random conical tilt reconstruction and subtomogram averaging, among other tasks. In this manuscript we provide the first detailed description of the high resolution single particle analysis pipeline and the philosophy behind its approach to the reconstruction problem. High resolution refinement is a fully automated process, and involves an advanced set of heuristics to select optimal algorithms for each specific refinement task. A gold standard FSC is produced automatically as part of refinement, providing a robust resolution estimate for the final map, and this is used to optimally filter the final CTF phase and amplitude corrected structure. Additional methods are in-place to reduce model bias during refinement, and to permit cross-validation using other computational methods. PMID:26931650

  3. High-resolution signal synthesis for time-frequency distributions

    SciTech Connect

    Cunningham, G.S.; Williams, W.J.

    1993-03-01

    Bilinear time-frequency distributions (TFDs) offer improved resolution over linear nine-frequency representations (TFRs), but many TFDs are costly to evaluate and are not associated with signal synthesis algorithms. Recently, the spectrogram (SP) decomposition and weighted reversal correlator decomposition have been used to define low-cost, high-resolution TFDs. In this paper, we show that the vector-valued ``square-root`` of a TFD (VVTFR) provides a representational underpinning for the TFD. By synthesizing signals from modified VVTFRs, we define high-resolution signal synthesis algorithms associated with TFDs. The signal analysis and synthesis packages can be implemented as weighted sums of SP/short-time Fourier Transform signal analysis and synthesis packages, which are widely available, allowing the interested non-specialist easy access to high-resolution methods.

  4. High-resolution signal synthesis for time-frequency distributions

    SciTech Connect

    Cunningham, G.S. ); Williams, W.J. . Dept. of Electrical Engineering and Computer Science)

    1993-01-01

    Bilinear time-frequency distributions (TFDs) offer improved resolution over linear nine-frequency representations (TFRs), but many TFDs are costly to evaluate and are not associated with signal synthesis algorithms. Recently, the spectrogram (SP) decomposition and weighted reversal correlator decomposition have been used to define low-cost, high-resolution TFDs. In this paper, we show that the vector-valued square-root'' of a TFD (VVTFR) provides a representational underpinning for the TFD. By synthesizing signals from modified VVTFRs, we define high-resolution signal synthesis algorithms associated with TFDs. The signal analysis and synthesis packages can be implemented as weighted sums of SP/short-time Fourier Transform signal analysis and synthesis packages, which are widely available, allowing the interested non-specialist easy access to high-resolution methods.

  5. High-resolution Urban Image Classification Using Extended Features

    SciTech Connect

    Vatsavai, Raju

    2011-01-01

    High-resolution image classification poses several challenges because the typical object size is much larger than the pixel resolution. Any given pixel (spectral features at that location) by itself is not a good indicator of the object it belongs to without looking at the broader spatial footprint. Therefore most modern machine learning approaches that are based on per-pixel spectral features are not very effective in high- resolution urban image classification. One way to overcome this problem is to extract features that exploit spatial contextual information. In this study, we evaluated several features in- cluding edge density, texture, and morphology. Several machine learning schemes were tested on the features extracted from a very high-resolution remote sensing image and results were presented.

  6. Microbeam High Angular Resolution Diffraction Applied to Optoelectronic Devices

    SciTech Connect

    Kazimirov, A.; Bilderback, D. H.; Sirenko, A. A.; Cai, Z.-H.; Lai, B.

    2007-01-19

    Collimating perfect crystal optics in a combination with the X-ray focusing optics has been applied to perform high angular resolution microbeam diffraction and scattering experiments on micron-size optoelectronic devices produced by modern semiconductor technology. At CHESS, we used capillary optics and perfect Si/Ge crystal(s) arrangement to perform X-ray standing waves, high angular-resolution diffraction and high resolution reciprocal space mapping analysis. At the APS, 2ID-D microscope beamline, we employed a phase zone plate producing a beam with the size of 240 nm in the horizontal plane and 350 nm in the vertical (diffraction) plane and a perfect Si (004) analyzer crystal to perform diffraction analysis of selectively grown InGaAsP and InGaAlAs-based waveguides with arc sec angular resolution.

  7. A Very High Spatial Resolution Detector for Small Animal PET

    SciTech Connect

    Kanai Shah, M.S.

    2007-03-06

    Positron Emission Tomography (PET) is an in vivo analog of autoradiography and has the potential to become a powerful new tool in imaging biological processes in small laboratory animals. PET imaging of small animals can provide unique information that can help in advancement of human disease models as well as drug development. Clinical PET scanners used for human imaging are bulky, expensive and do not have adequate spatial resolution for small animal studies. Hence, dedicated, low cost instruments are required for conducting small animal studies with higher spatial resolution than what is currently achieved with clinical as well as dedicated small animal PET scanners. The goal of the proposed project is to investigate a new all solid-state detector design for small animal PET imaging. Exceptionally high spatial resolution, good timing resolution, and excellent energy resolution are expected from the proposed detector design. The Phase I project was aimed at demonstrating the feasibility of producing high performance solid-state detectors that provide high sensitivity, spatial resolution, and timing characteristics. Energy resolution characteristics of the new detector were also investigated. The goal of the Phase II project is to advance the promising solid-state detector technology for small animal PET and determine its full potential. Detectors modules will be built and characterized and finally, a bench-top small animal PET system will be assembled and evaluated.

  8. High resolution surface plasmon microscopy for cell imaging

    NASA Astrophysics Data System (ADS)

    Argoul, F.; Monier, K.; Roland, T.; Elezgaray, J.; Berguiga, L.

    2010-04-01

    We introduce a new non-labeling high resolution microscopy method for cellular imaging. This method called SSPM (Scanning Surface Plasmon Microscopy) pushes down the resolution limit of surface plasmon resonance imaging (SPRi) to sub-micronic scales. High resolution SPRi is obtained by the surface plasmon lauching with a high numerical aperture objective lens. The advantages of SPPM compared to other high resolution SPRi's rely on three aspects; (i) the interferometric detection of the back reflected light after plasmon excitation, (ii) the twodimensional scanning of the sample for image reconstruction, (iii) the radial polarization of light, enhancing both resolution and sensitivity. This microscope can afford a lateral resolution of - 150 nm in liquid environment and - 200 nm in air. We present in this paper images of IMR90 fibroblasts obtained with SSPM in dried environment. Internal compartments such as nucleus, nucleolus, mitochondria, cellular and nuclear membrane can be recognized without labelling. We propose an interpretation of the ability of SSPM to reveal high index contrast zones by a local decomposition of the V (Z) function describing the response of the SSPM.

  9. High level white noise generator

    DOEpatents

    Borkowski, Casimer J.; Blalock, Theron V.

    1979-01-01

    A wide band, stable, random noise source with a high and well-defined output power spectral density is provided which may be used for accurate calibration of Johnson Noise Power Thermometers (JNPT) and other applications requiring a stable, wide band, well-defined noise power spectral density. The noise source is based on the fact that the open-circuit thermal noise voltage of a feedback resistor, connecting the output to the input of a special inverting amplifier, is available at the amplifier output from an equivalent low output impedance caused by the feedback mechanism. The noise power spectral density level at the noise source output is equivalent to the density of the open-circuit thermal noise or a 100 ohm resistor at a temperature of approximately 64,000 Kelvins. The noise source has an output power spectral density that is flat to within 0.1% (0.0043 db) in the frequency range of from 1 KHz to 100 KHz which brackets typical passbands of the signal-processing channels of JNPT's. Two embodiments, one of higher accuracy that is suitable for use as a standards instrument and another that is particularly adapted for ambient temperature operation, are illustrated in this application.

  10. High Resolution Hurricane Storm Surge and Inundation Modeling (Invited)

    NASA Astrophysics Data System (ADS)

    Luettich, R.; Westerink, J. J.

    2010-12-01

    Coastal counties are home to nearly 60% of the U.S. population and industry that accounts for over 16 million jobs and 10% of the U.S. annual gross domestic product. However, these areas are susceptible to some of the most destructive forces in nature, including tsunamis, floods, and severe storm-related hazards. Since 1900, tropical cyclones making landfall on the US Gulf of Mexico Coast have caused more than 9,000 deaths; nearly 2,000 deaths have occurred during the past half century. Tropical cyclone-related adjusted, annualized losses in the US have risen from 1.3 billion from 1949-1989, to 10.1 billion from 1990-1995, and $35.8 billion per year for the period 2001-2005. The risk associated with living and doing business in the coastal areas that are most susceptible to tropical cyclones is exacerbated by rising sea level and changes in the characteristics of severe storms associated with global climate change. In the five years since hurricane Katrina devastated the northern Gulf of Mexico Coast, considerable progress has been made in the development and utilization of high resolution coupled storm surge and wave models. Recent progress will be presented with the ADCIRC + SWAN storm surge and wave models. These tightly coupled models use a common unstructured grid in the horizontal that is capable of covering large areas while also providing high resolution (i.e., base resolution down to 20m plus smaller subgrid scale features such as sea walls and levees) in areas that are subject to surge and inundation. Hydrodynamic friction and overland winds are adjusted to account for local land cover. The models scale extremely well on modern high performance computers allowing rapid turnaround on large numbers of compute cores. The models have been adopted for FEMA National Flood Insurance Program studies, hurricane protection system design and risk analysis, and quasi-operational forecast systems for several regions of the country. They are also being evaluated as

  11. Dual camera system for acquisition of high resolution images

    NASA Astrophysics Data System (ADS)

    Papon, Jeremie A.; Broussard, Randy P.; Ives, Robert W.

    2007-02-01

    Video surveillance is ubiquitous in modern society, but surveillance cameras are severely limited in utility by their low resolution. With this in mind, we have developed a system that can autonomously take high resolution still frame images of moving objects. In order to do this, we combine a low resolution video camera and a high resolution still frame camera mounted on a pan/tilt mount. In order to determine what should be photographed (objects of interest), we employ a hierarchical method which first separates foreground from background using a temporal-based median filtering technique. We then use a feed-forward neural network classifier on the foreground regions to determine whether the regions contain the objects of interest. This is done over several frames, and a motion vector is deduced for the object. The pan/tilt mount then focuses the high resolution camera on the next predicted location of the object, and an image is acquired. All components are controlled through a single MATLAB graphical user interface (GUI). The final system we present will be able to detect multiple moving objects simultaneously, track them, and acquire high resolution images of them. Results will demonstrate performance tracking and imaging varying numbers of objects moving at different speeds.

  12. [Extracting municipal solid waste dumps based on high resolution images].

    PubMed

    Zhang, Fang-Li; Du, Shi-Hong; Guo, Zhou

    2013-08-01

    The dramatically increasing informal MSW dumps are endangering the urban environment. Remote sensing (RS) technologies are more efficient to monitor and manage municipal solid wastes (MSW) than traditional survey-based methods. In high spatial resolution remotely sensed images, these irregularly distributed dumps have complex compositions and strong heterogeneities, thus it is still hard to extract them automatically no matter the pixel-or object-based image analysis method is used. Therefore, based on the analysis of MSW characteristics, the present study develops a multiresolution strategy to extract MSW dumps by combining image features at both high resolution and resampled low heterogeneity images, while the high resolution images can provide detailed information and the low resolution images can suppress the strong heterogeneities of informal MSW dumps. Taking the QuickBird image covering part of Beijing as an example, this multi-resolution strategy produced a high accuracy (75%), indicating that this multi-resolution strategy is quite effective for extracting the open-air informal MSW dumps. PMID:24159838

  13. A miniature high-resolution accelerometer utilizing electron tunneling

    NASA Technical Reports Server (NTRS)

    Rockstad, Howard K.; Kenny, T. W.; Reynolds, J. K.; Kaiser, W. J.; Vanzandt, T. R.; Gabrielson, Thomas B.

    1992-01-01

    New methods have been developed to implement high-resolution position sensors based on electron tunneling. These methods allow miniaturization while utilizing the position sensitivity of electron tunneling to give high resolution. A single-element tunneling accelerometer giving a displacement resolution of 0.002 A/sq rt Hz at 10 Hz, corresponding to an acceleration resolution of 5 x 10 exp -8 g/sq rt Hz, is described. A new dual-element tunneling structure which overcomes the narrow bandwidth limitations of a single-element structure is described. A sensor with an operating range of 5 Hz to 10 kHz, which can have applications as an acoustic sensor, is discussed. Noise is analyzed for fundamental thermal vibration of the suspended masses and is compared to electronic noise. It is shown that miniature tunnel accelerometers can achieve resolution such that thermal noise in the suspended masses is the dominant cause of the resolution limit. With a proof mass of order 100 mg, noise analysis predicts limiting resolutions approaching 10 exp -9 g/sq rt Hz in a 300 Hz band and 10 exp -8 g/sq rt Hz at 1 kHz.

  14. Exploring for subtle traps with high-resolution paleogeographic maps

    SciTech Connect

    Bulling, T.B.; Breyer, J.A.

    1988-01-01

    High-resolution paleogeographic maps depicting the depositional history of the Reklaw 1 interval provide a basis for prospecting for subtle traps in the updip Reklaw trend in south Texas. The Reklaw 1 interval began with sand being carried southwest by longshore currents to form the barrier bar that forms the reservoir in Atkinson field. The hydrocarbons are trapped by the updip pinch-out of barrier-bar sand into lagoonal mud. Stratigraphic traps similar to Atkinson field could be present along depositional strike if the sand in the field were part of a more extensive-bar system. After the barrier bar formed, distributary-mouth bars prograded seaward depositing the bar-finger sands that are the reservoirs in Hysaw and Flax fields. Subtle structural traps could be present where small down-to-the-north faults associated with the Sample fault system cut the bar-finger sands downdip from the established production. Farther down paleoslope, the distributary channels began to bifurcate and the distributary-mouth bar coalesced to form a broad delt-front sheet sand. Burnell, Hondo Creek, and Runge West fields produce from this sheet sand near the unstable shelf margin. A rapid rise in relative sea level terminated deposition of the Reklaw 1 interval. Many of the oil and gas fields remaining to be discovered in the United States are in mature petroleum provinces where much of the remaining oil and gas probably resides in subtle traps. High-resolution paleogeographic maps may be a key to finding these subtle traps.

  15. High-resolution climate simulation of the last glacial maximum

    SciTech Connect

    Erickson III, David J

    2008-01-01

    The climate of the last glacial maximum (LGM) is simulated with a high-resolution atmospheric general circulation model, the NCAR CCM3 at spectral truncation of T170, corresponding to a grid cell size of roughly 75 km. The purpose of the study is to assess whether there are significant benefits from the higher resolution simulation compared to the lower resolution simulation associated with the role of topography. The LGM simulations were forced with modified CLIMAP sea ice distribution and sea surface temperatures (SST) reduced by 1 C, ice sheet topography, reduced CO{sub 2}, and 21,000 BP orbital parameters. The high-resolution model captures modern climate reasonably well, in particular the distribution of heavy precipitation in the tropical Pacific. For the ice age case, surface temperature simulated by the high-resolution model agrees better with those of proxy estimates than does the low-resolution model. Despite the fact that tropical SSTs were only 2.1 C less than the control run, there are many lowland tropical land areas 4-6 C colder than present. Comparison of T170 model results with the best constrained proxy temperature estimates (noble gas concentrations in groundwater) now yield no significant differences between model and observations. There are also significant upland temperature changes in the best resolved tropical mountain belt (the Andes). We provisionally attribute this result in part as resulting from decreased lateral mixing between ocean and land in a model with more model grid cells. A longstanding model-data discrepancy therefore appears to be resolved without invoking any unusual model physics. The response of the Asian summer monsoon can also be more clearly linked to local geography in the high-resolution model than in the low-resolution model; this distinction should enable more confident validation of climate proxy data with the high-resolution model. Elsewhere, an inferred salinity increase in the subtropical North Atlantic may have

  16. High-energy resolution alpha spectrometry using cryogenic detectors.

    PubMed

    Leblanc, E; Coron, N; Leblanc, J; de Marcillac, P; Bouchard, J; Plagnard, J

    2006-01-01

    Applications such as environment monitoring implying alpha emitters activity measurement associated with isotope identification, require high-energy resolution detectors. Conventional silicon detectors are inexpensive therefore widely used, although intrinsically limited in energy resolution. Thermal detection principle of cryogenic detectors introduces a breakthrough in alpha particle measurement. For the first time, spectra with 5.5 keV FWHM energy resolution have been obtained for several external alpha emitting sources using a copper-germanium bolometer specially developed for alpha spectrometry. PMID:16618545

  17. High resolution seismic stratigraphy of Tampa Bay, Florida

    SciTech Connect

    Tihansky, A.B.; Hine, A.C.; Locker, S.D.; Doyle, L.D. . Dept. of Marine Science)

    1993-03-01

    Tampa Bay is one of two large embayments that interrupt the broad, regional nature of the carbonate ramp of the west coast of the Florida carbonate platform. It is believed to have formed as a result of preferential dissolution of the Cenozoic limestones beneath it. Highly reactive freshwater systems became hydrologically focused in the bay region as the surface and groundwater systems established themselves during sea-level lowstands. This weakening of the underlying limestone resulted in extensive karstification, including warping, subsidence, sinkhole and spring formation. Over 120 miles of high resolution seismic reflection data were collected within Tampa Bay. This record has been tied into 170 core borings taken from within the bay. This investigation has found three major seismic stratigraphic sequences beneath the bay. The lowermost sequence is probably of Miocene age. Its surface is highly irregular due to erosion and dissolution and exhibits a great deal of vertical relief as well as gentler undulations or warping. Much of the middle sequence consists of low angle clinoforms that gently downlap and fill in the underlying karst features. The uppermost sequence is a discontinuous unit comprised of horizontal to low angle clinoforms that are local in their extent. The recent drainage and sedimentation patterns within the bay area are related to the underlying structure controlled by the Miocene karst activity.

  18. The dynamic solar chromosphere: recent advances from high resolution telescopes

    NASA Astrophysics Data System (ADS)

    Tziotziou, Konstantinos; Tsiropoula, Georgia

    This review focuses on the solar chromosphere, a very inhomogeneous and dynamic layer that exhibits phenomena on a large range of spatial and temporal scales. High-resolution observa-tions from existing telescopes (DST, SST, DOT), as well as long-duration observations with Hinode's SOT employing lines such as the Ca II infrared lines, the Ca II HK and above all the Hα line reveal an incredibly rich, dynamic and highly structured environment, both in quiet and active regions. The fine-structure chromosphere, is mainly constituted by fibrilar features that connect various parts of active regions or span across network cell interiors. We discuss this highly dynamical solar chromosphere, especially below the magnetic canopy, which is gov-erned by flows reflecting both the complex geometry and dynamics of the magnetic field and the propagation and dissipation of waves in the different atmospheric layers. A comprehensive view of the fine-structure chromosphere requires deep understanding of the physical processes involved, investigation of the intricate link with structures/processes at lower photospheric lev-els and analysis of its impact on the mass and energy transport to higher atmospheric layers through flows resulting from different physical processes such as magnetic reconnection and waves. Furthermore, we assess the challenges facing theory and numerical modelling which require the inclusion of several physical ingredients, such as non-LTE and three-dimensional numerical simulations.

  19. A parallel solution for high resolution histological image analysis.

    PubMed

    Bueno, G; González, R; Déniz, O; García-Rojo, M; González-García, J; Fernández-Carrobles, M M; Vállez, N; Salido, J

    2012-10-01

    This paper describes a general methodology for developing parallel image processing algorithms based on message passing for high resolution images (on the order of several Gigabytes). These algorithms have been applied to histological images and must be executed on massively parallel processing architectures. Advances in new technologies for complete slide digitalization in pathology have been combined with developments in biomedical informatics. However, the efficient use of these digital slide systems is still a challenge. The image processing that these slides are subject to is still limited both in terms of data processed and processing methods. The work presented here focuses on the need to design and develop parallel image processing tools capable of obtaining and analyzing the entire gamut of information included in digital slides. Tools have been developed to assist pathologists in image analysis and diagnosis, and they cover low and high-level image processing methods applied to histological images. Code portability, reusability and scalability have been tested by using the following parallel computing architectures: distributed memory with massive parallel processors and two networks, INFINIBAND and Myrinet, composed of 17 and 1024 nodes respectively. The parallel framework proposed is flexible, high performance solution and it shows that the efficient processing of digital microscopic images is possible and may offer important benefits to pathology laboratories. PMID:22522064

  20. Resolution-recovery-embedded image reconstruction for a high-resolution animal SPECT system.

    PubMed

    Zeraatkar, Navid; Sajedi, Salar; Farahani, Mohammad Hossein; Arabi, Hossein; Sarkar, Saeed; Ghafarian, Pardis; Rahmim, Arman; Ay, Mohammad Reza

    2014-11-01

    The small-animal High-Resolution SPECT (HiReSPECT) is a dedicated dual-head gamma camera recently designed and developed in our laboratory for imaging of murine models. Each detector is composed of an array of 1.2 × 1.2 mm(2) (pitch) pixelated CsI(Na) crystals. Two position-sensitive photomultiplier tubes (H8500) are coupled to each head's crystal. In this paper, we report on a resolution-recovery-embedded image reconstruction code applicable to the system and present the experimental results achieved using different phantoms and mouse scans. Collimator-detector response functions (CDRFs) were measured via a pixel-driven method using capillary sources at finite distances from the head within the field of view (FOV). CDRFs were then fitted by independent Gaussian functions. Thereafter, linear interpolations were applied to the standard deviation (σ) values of the fitted Gaussians, yielding a continuous map of CDRF at varying distances from the head. A rotation-based maximum-likelihood expectation maximization (MLEM) method was used for reconstruction. A fast rotation algorithm was developed to rotate the image matrix according to the desired angle by means of pre-generated rotation maps. The experiments demonstrated improved resolution utilizing our resolution-recovery-embedded image reconstruction. While the full-width at half-maximum (FWHM) radial and tangential resolution measurements of the system were over 2 mm in nearly all positions within the FOV without resolution recovery, reaching around 2.5 mm in some locations, they fell below 1.8 mm everywhere within the FOV using the resolution-recovery algorithm. The noise performance of the system was also acceptable; the standard deviation of the average counts per voxel in the reconstructed images was 6.6% and 8.3% without and with resolution recovery, respectively. PMID:24986422

  1. High resolution nitrogen dioxide observations: retrieval, evaluation, and interpretation

    NASA Astrophysics Data System (ADS)

    Lamsal, L. N.; Janz, S. J.; Krotkov, N. A.; Pickering, K. E.; Kowalewski, M. G.; Loughner, C.; Spurr, R. J. D.; Crawford, J. H.

    2015-12-01

    The Airborne Compact Atmospheric Mapper (ACAM) deployed during the DISCOVER-AQ Maryland field campaign made hyperspectral remote sensing measurements in the 304-910 nm range allowing observations of several tropospheric pollutants including nitrogen dioxide (NO2) at an unprecedented spatial resolution of 1.5x0.75 km2. We apply the DOAS method, include high resolution information for surface reflectivity and vertical distributions of NO2 and aerosols, and account for temporal variation in atmospheric NO2 to retrieve lower tropospheric NO2 column. We compare NO2 from ACAM with observations from in-situ aircraft, ground-based PANDORA, and space-based OMI, and NO2 simulation from air quality models. The high resolution ACAM measurements offer not only new insights into our understanding of atmospheric composition and chemistry through observation of sub-sampling variability in typical satellite and model resolutions, but also opportunities for algorithm improvements for upcoming geostationary air quality missions.

  2. Performance of a High Resolution Cavity Beam Position Monitor System

    SciTech Connect

    Walston, S; Boogert, S; Chung, C; Fitsos, P; Frisch, J; Gronberg, J; Hayano, H; Honda, Y; Kolomensky, Y; Lyapin, A; Malton, S; May, J; McCormick, D; Meller, R; Miller, D; Orimoto, T; Ross, M; Slater, M; Smith, S; Smith, T; Terunuma, N; Thomson, M; Urakawa, J; Vogel, V; Ward, D; White, G

    2006-12-18

    It has been estimated that an RF cavity Beam Position Monitor (BPM) could provide a position measurement resolution of less than one nanometer. We have developed a high resolution cavity BPM and associated electronics. A triplet comprised of these BPMs was installed in the extraction line of the Accelerator Test Facility (ATF) at the High Energy Accelerator Research Organization (KEK) for testing with its ultra-low emittance beam. The three BPMs were each rigidly mounted inside an alignment frame on six variable-length struts which could be used to move the BPMs in position and angle. We have developed novel methods for extracting the position and tilt information from the BPM signals including a robust calibration algorithm which is immune to beam jitter. To date, we have demonstrated a position resolution of 15.6 nm and a tilt resolution of 2.1 {micro}rad over a dynamic range of approximately {+-} 20 {micro}m.

  3. Performance of a High Resolution Cavity Beam Position Monitor System

    SciTech Connect

    Walston, Sean; Boogert, Stewart; Chung, Carl; Fitsos, Joe; Frisch, Joe; Gronberg, Jeff; Hayano, Hitoshi; Honda, Yosuke; Kolomensky, Yury; Lyapin, Alexey; Malton, Stephen; May, Justin; McCormick, Douglas; Meller, Robert; Miller, David John; Orimoto, Toyoko; Ross, Marc; Slater, Mark; Smith, Steve; Smith, Tonee; Terunuma, Nobuhiro; /Fermilab /UC, Berkeley /LBL, Berkeley /Cambridge U. /Royal Holloway, U. of London /Cornell U., LNS /LLNL, Livermore /University Coll. London /SLAC /Caltech /KEK, Tsukuba

    2007-06-08

    It has been estimated that an RF cavity Beam Position Monitor (BPM) could provide a position measurement resolution of less than one nanometer. We have developed a high resolution cavity BPM and associated electronics. A triplet comprised of these BPMs was installed in the extraction line of the Accelerator Test Facility (ATF) at the High Energy Accelerator Research Organization (KEK) for testing with its ultra-low emittance beam. The three BPMs were each rigidly mounted inside an alignment frame on six variable-length struts which could be used to move the BPMs in position and angle. We have developed novel methods for extracting the position and tilt information from the BPM signals including a robust calibration algorithm which is immune to beam jitter. To date, we have demonstrated a position resolution of 15.6 nm and a tilt resolution of 2.1 {mu}rad over a dynamic range of approximately {+-} 20 {mu}m.

  4. THz holography in reflection using a high resolution microbolometer array.

    PubMed

    Zolliker, Peter; Hack, Erwin

    2015-05-01

    We demonstrate a digital holographic setup for Terahertz imaging of surfaces in reflection. The set-up is based on a high-power continuous wave (CW) THz laser and a high-resolution (640 × 480 pixel) bolometer detector array. Wave propagation to non-parallel planes is used to reconstruct the object surface that is rotated relative to the detector plane. In addition we implement synthetic aperture methods for resolution enhancement and compare Fourier transform phase retrieval to phase stepping methods. A lateral resolution of 200 μm and a relative phase sensitivity of about 0.4 rad corresponding to a depth resolution of 6 μm are estimated from reconstructed images of two specially prepared test targets, respectively. We highlight the use of digital THz holography for surface profilometry as well as its potential for video-rate imaging. PMID:25969190

  5. Extracting low-resolution river networks from high-resolution digital elevation models

    USGS Publications Warehouse

    Olivera, F.; Lear, M.S.; Famiglietti, J.S.; Asante, Kwasi

    2002-01-01

    Including a global river network in the land component of global climate models (GCMs) is necessary in order to provide a more complete representation of the hydrologic cycle. The process of creating these networks is called river network upscaling and consists of lowering the resolution of already available fine networks to make them compatible with GCMs. Fine-resolution river networks have a level of detail appropriate for analysis at the watershed scale but are too intensive for global hydrologic studies. A river network upscaling algorithm, which processes fine-resolution digital elevation models to determine the flow directions that best describe the flow patterns in a coarser user-defined scale, is presented. The objectives of this study were to develop an algorithm that advances the previous work in the field by being applicable at a global scale, allowing for the upscaling to be performed in a projected environment, and generating evenly distributed flow directions.

  6. The Goddard High Resolution Spectrograph: Instrument, goals, and science results

    NASA Astrophysics Data System (ADS)

    Brandt, J. C.; Heap, S. R.; Beaver, E. A.; Boggess, A.; Carpenter, K. G.; Ebbets, D. C.; Hutchings, J. B.; Jura, M.; Leckrone, D. S.; Linsky, J. L.; Maran, S. P.; Savage, B. D.; Smith, A. M.; Trafton, L. M.; Walter, F. M.; Weymann, R. J.; Ake, T. B.; Bruhweiler, F.; Cardelli, J. A.; Lindler, D. J.; Malumuth, E.; Randall, C. E.; Robinson, R.; Shore, S. N.; Wahlgren, G.

    1994-08-01

    The Goddard High Resolution Spectrograph (GHRS), currently in Earth orbit on the Hubble Space Telescope (HST), operates in the wavelength range 1150-3200 A with spectral resolutions (lambda/delta lambda) of approximately 2 x 103, 2 x 104, and 1 x 103. The instrument and its development from inception, its current status, the approach to operations, representative results in the major areas of the scientific goals, and prospects for the future are described.

  7. High-resolution radiography by means of a hodoscope

    DOEpatents

    De Volpi, Alexander

    1978-01-01

    The fast neutron hodoscope, a device that produces neutron radiographs with coarse space resolution in a short time, is modified to produce neutron or gamma radiographs of relatively thick samples and with high space resolution. The modification comprises motorizing a neutron and gamma collimator to permit a controlled scanning pattern, simultaneous collection of data in a number of hodoscope channels over a period of time, and computerized image reconstruction of the data thus gathered.

  8. The Goddard High Resolution Spectrograph: Instrument, goals, and science results

    NASA Technical Reports Server (NTRS)

    Brandt, J. C.; Heap, S. R.; Beaver, E. A.; Boggess, A.; Carpenter, K. G.; Ebbets, D. C.; Hutchings, J. B.; Jura, M.; Leckrone, D. S.; Linsky, J. L.

    1994-01-01

    The Goddard High Resolution Spectrograph (GHRS), currently in Earth orbit on the Hubble Space Telescope (HST), operates in the wavelength range 1150-3200 A with spectral resolutions (lambda/delta lambda) of approximately 2 x 10(exp 3), 2 x 10(exp 4), and 1 x 10(exp 3). The instrument and its development from inception, its current status, the approach to operations, representative results in the major areas of the scientific goals, and prospects for the future are described.

  9. Infrared emission high spectral resolution atlas of the stratospheric limb

    NASA Technical Reports Server (NTRS)

    Maguire, William C.; Kunde, Virgil G.; Herath, Lawrence W.

    1989-01-01

    An atlas of high resolution infrared emission spectra identifies a number of gaseous atmospheric features significant to stratospheric chemistry in the 770-900/cm and 1100-1360/cm regions at six zenith angles from 86.7 to 95.1 deg. A balloon-borne Michelson interferometer was flown to obtain about 0.03/cm resolution spectra. Two 10/cm extracts are presented here.

  10. Applications of high-resolution remote sensing image data

    NASA Technical Reports Server (NTRS)

    Strome, W. M.; Leckie, D.; Miller, J.; Buxton, R.

    1990-01-01

    There are many situations in which the image resolution of satellite data is insufficient to provide the detail required for resource management and environmental monitoring. This paper will focus on applications of high-resolution (0.4 to 10 m) airborne multispectral and imaging spectrometer data acquired in Canada using the MEIS II multispectral line imager and the PMI imaging spectrometer. Applications discussed will include forestry, mapping, and geobotany.

  11. Isotope specific resolution recovery image reconstruction in high resolution PET imaging

    SciTech Connect

    Kotasidis, Fotis A.; Angelis, Georgios I.; Anton-Rodriguez, Jose; Matthews, Julian C.; Reader, Andrew J.; Zaidi, Habib

    2014-05-15

    Purpose: Measuring and incorporating a scanner-specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However, due to the short half-life of clinically used isotopes, other long-lived isotopes not used in clinical practice are used to perform the PSF measurements. As such, non-optimal PSF models that do not correspond to those needed for the data to be reconstructed are used within resolution modeling (RM) image reconstruction, usually underestimating the true PSF owing to the difference in positron range. In high resolution brain and preclinical imaging, this effect is of particular importance since the PSFs become more positron range limited and isotope-specific PSFs can help maximize the performance benefit from using resolution recovery image reconstruction algorithms. Methods: In this work, the authors used a printing technique to simultaneously measure multiple point sources on the High Resolution Research Tomograph (HRRT), and the authors demonstrated the feasibility of deriving isotope-dependent system matrices from fluorine-18 and carbon-11 point sources. Furthermore, the authors evaluated the impact of incorporating them within RM image reconstruction, using carbon-11 phantom and clinical datasets on the HRRT. Results: The results obtained using these two isotopes illustrate that even small differences in positron range can result in different PSF maps, leading to further improvements in contrast recovery when used in image reconstruction. The difference is more pronounced in the centre of the field-of-view where the full width at half maximum (FWHM) from the positron range has a larger contribution to the overall FWHM compared to the edge where the parallax error dominates the overall FWHM. Conclusions: Based on the proposed methodology, measured isotope-specific and spatially variant PSFs can be reliably derived and used for improved spatial resolution and variance performance in resolution

  12. Optimizing High Level Waste Disposal

    SciTech Connect

    Dirk Gombert

    2005-09-01

    If society is ever to reap the potential benefits of nuclear energy, technologists must close the fuel-cycle completely. A closed cycle equates to a continued supply of fuel and safe reactors, but also reliable and comprehensive closure of waste issues. High level waste (HLW) disposal in borosilicate glass (BSG) is based on 1970s era evaluations. This host matrix is very adaptable to sequestering a wide variety of radionuclides found in raffinates from spent fuel reprocessing. However, it is now known that the current system is far from optimal for disposal of the diverse HLW streams, and proven alternatives are available to reduce costs by billions of dollars. The basis for HLW disposal should be reassessed to consider extensive waste form and process technology research and development efforts, which have been conducted by the United States Department of Energy (USDOE), international agencies and the private sector. Matching the waste form to the waste chemistry and using currently available technology could increase the waste content in waste forms to 50% or more and double processing rates. Optimization of the HLW disposal system would accelerate HLW disposition and increase repository capacity. This does not necessarily require developing new waste forms, the emphasis should be on qualifying existing matrices to demonstrate protection equal to or better than the baseline glass performance. Also, this proposed effort does not necessarily require developing new technology concepts. The emphasis is on demonstrating existing technology that is clearly better (reliability, productivity, cost) than current technology, and justifying its use in future facilities or retrofitted facilities. Higher waste processing and disposal efficiency can be realized by performing the engineering analyses and trade-studies necessary to select the most efficient methods for processing the full spectrum of wastes across the nuclear complex. This paper will describe technologies being

  13. Towards a High-Resolution Global Inundation Delineation Dataset

    NASA Astrophysics Data System (ADS)

    Fluet-Chouinard, E.; Lehner, B.

    2011-12-01

    Although their importance for biodiversity, flow regulation and ecosystem service provision is widely recognized, wetlands and temporarily inundated landscapes remain poorly mapped globally because of their inherent elusive nature. Inventorying of wetland resources has been identified in international agreements as an essential component of appropriate conservation efforts and management initiatives of these threatened ecosystems. However, despite recent advances in remote sensing surface water monitoring, current inventories of surface water variations remain incomplete at the regional-to-global scale due to methodological limitations restricting truly global application. Remote sensing wetland applications such as SAR L-band are particularly constrained by image availability and heterogeneity of acquisition dates, while coarse resolution passive microwave and multi-sensor methods cannot discriminate distinct surface water bodies. As a result, the most popular global wetland dataset remains to this day the Global Lake & Wetland Database (Lehner and Doll, 2004) a spatially inconsistent database assembled from various existing data sources. The approach taken in this project circumvents the limitations of current global wetland monitoring methods by combining globally available topographic and hydrographic data to downscale coarse resolution global inundation data (Prigent et al., 2007) and thus create a superior inundation delineation map product. The developed procedure downscales inundation data from the coarse resolution (~27km) of current passive microwave sensors to the finer spatial resolution (~500m) of the topographic and hydrographic layers of HydroSHEDS' data suite (Lehner et al., 2006), while retaining the high temporal resolution of the multi-sensor inundation dataset. From the downscaling process emerges new information on the specific location of inundation, but also on its frequency and duration. The downscaling algorithm employs a decision tree

  14. A High Resolution On-Chip Delay Sensor with Low Supply-Voltage Sensitivity for High-Performance Electronic Systems

    PubMed Central

    Sheng, Duo; Lai, Hsiu-Fan; Chan, Sheng-Min; Hong, Min-Rong

    2015-01-01

    An all-digital on-chip delay sensor (OCDS) circuit with high delay-measurement resolution and low supply-voltage sensitivity for efficient detection and diagnosis in high-performance electronic system applications is presented. Based on the proposed delay measurement scheme, the quantization resolution of the proposed OCDS can be reduced to several picoseconds. Additionally, the proposed cascade-stage delay measurement circuit can enhance immunity to supply-voltage variations of the delay measurement resolution without extra self-biasing or calibration circuits. Simulation results show that the delay measurement resolution can be improved to 1.2 ps; the average delay resolution variation is 0.55% with supply-voltage variations of ±10%. Moreover, the proposed delay sensor can be implemented in an all-digital manner, making it very suitable for high-performance electronic system applications as well as system-level integration. PMID:25688590

  15. High-resolution land cover classification using low resolution global data

    NASA Astrophysics Data System (ADS)

    Carlotto, Mark J.

    2013-05-01

    A fusion approach is described that combines texture features from high-resolution panchromatic imagery with land cover statistics derived from co-registered low-resolution global databases to obtain high-resolution land cover maps. The method does not require training data or any human intervention. We use an MxN Gabor filter bank consisting of M=16 oriented bandpass filters (0-180°) at N resolutions (3-24 meters/pixel). The size range of these spatial filters is consistent with the typical scale of manmade objects and patterns of cultural activity in imagery. Clustering reduces the complexity of the data by combining pixels that have similar texture into clusters (regions). Texture classification assigns a vector of class likelihoods to each cluster based on its textural properties. Classification is unsupervised and accomplished using a bank of texture anomaly detectors. Class likelihoods are modulated by land cover statistics derived from lower resolution global data over the scene. Preliminary results from a number of Quickbird scenes show our approach is able to classify general land cover features such as roads, built up area, forests, open areas, and bodies of water over a wide range of scenes.

  16. Secure distribution for high resolution remote sensing images

    NASA Astrophysics Data System (ADS)

    Liu, Jin; Sun, Jing; Xu, Zheng Q.

    2010-09-01

    The use of remote sensing images collected by space platforms is becoming more and more widespread. The increasing value of space data and its use in critical scenarios call for adoption of proper security measures to protect these data against unauthorized access and fraudulent use. In this paper, based on the characteristics of remote sensing image data and application requirements on secure distribution, a secure distribution method is proposed, including users and regions classification, hierarchical control and keys generation, and multi-level encryption based on regions. The combination of the three parts can make that the same remote sensing images after multi-level encryption processing are distributed to different permission users through multicast, but different permission users can obtain different degree information after decryption through their own decryption keys. It well meets user access control and security needs in the process of high resolution remote sensing image distribution. The experimental results prove the effectiveness of the proposed method which is suitable for practical use in the secure transmission of remote sensing images including confidential information over internet.

  17. Extension of least squares spectral resolution algorithm to high-resolution lipidomics data.

    PubMed

    Zeng, Ying-Xu; Mjøs, Svein Are; David, Fabrice P A; Schmid, Adrien W

    2016-03-31

    Lipidomics, which focuses on the global study of molecular lipids in biological systems, has been driven tremendously by technical advances in mass spectrometry (MS) instrumentation, particularly high-resolution MS. This requires powerful computational tools that handle the high-throughput lipidomics data analysis. To address this issue, a novel computational tool has been developed for the analysis of high-resolution MS data, including the data pretreatment, visualization, automated identification, deconvolution and quantification of lipid species. The algorithm features the customized generation of a lipid compound library and mass spectral library, which covers the major lipid classes such as glycerolipids, glycerophospholipids and sphingolipids. Next, the algorithm performs least squares resolution of spectra and chromatograms based on the theoretical isotope distribution of molecular ions, which enables automated identification and quantification of molecular lipid species. Currently, this methodology supports analysis of both high and low resolution MS as well as liquid chromatography-MS (LC-MS) lipidomics data. The flexibility of the methodology allows it to be expanded to support more lipid classes and more data interpretation functions, making it a promising tool in lipidomic data analysis. PMID:26965325

  18. High-performance VGA-resolution digital color CMOS imager

    NASA Astrophysics Data System (ADS)

    Agwani, Suhail; Domer, Steve; Rubacha, Ray; Stanley, Scott

    1999-04-01

    This paper discusses the performance of a new VGA resolution color CMOS imager developed by Motorola on a 0.5micrometers /3.3V CMOS process. This fully integrated, high performance imager has on chip timing, control, and analog signal processing chain for digital imaging applications. The picture elements are based on 7.8micrometers active CMOS pixels that use pinned photodiodes for higher quantum efficiency and low noise performance. The image processing engine includes a bank of programmable gain amplifiers, line rate clamping for dark offset removal, real time auto white balancing, per column gain and offset calibration, and a 10 bit pipelined RSD analog to digital converter with a programmable input range. Post ADC signal processing includes features such as bad pixel replacement based on user defined thresholds levels, 10 to 8 bit companding and 5 tap FIR filtering. The sensor can be programmed via a standard I2C interface that runs on 3.3V clocks. Programmable features include variable frame rates using a constant frequency master clock, electronic exposure control, continuous or single frame capture, progressive or interlace scanning modes. Each pixel is individually addressable allowing region of interest imaging and image subsampling. The sensor operates with master clock frequencies of up to 13.5MHz resulting in 30FPS. A total programmable gain of 27dB is available. The sensor power dissipation is 400mW at full speed of operation. The low noise design yields a measured 'system on a chip' dynamic range of 50dB thus giving over 8 true bits of resolution. Extremely high conversion gain result in an excellent peak sensitivity of 22V/(mu) J/cm2 or 3.3V/lux-sec. This monolithic image capture and processing engine represent a compete imaging solution making it a true 'camera on a chip'. Yet in its operation it remains extremely easy to use requiring only one clock and a 3.3V power supply. Given the available features and performance levels, this sensor will be

  19. High resolution BPMS with integrated gain correction system

    SciTech Connect

    Wendt, M.; Briegel, C.; Eddy, N.; Fellenz, B.; Gianfelice, E.; Prieto, P.; Rechenmacher, R.; Voy, D.; Terunuma, N.; Urakawa, J.; /KEK, Tsukuba

    2009-08-01

    High resolution beam position monitors (BPM) are an essential tool to achieve and reproduce a low vertical beam emittance at the KEK Accelerator Test Facility (ATF) damping ring. The ATF damping ring (DR) BPMs are currently upgraded with new high resolution read-out electronics. Based on analog and digital down-conversion techniques, the upgrade includes an automatic gain calibration system to correct for slow drift effects and ensure high reproducible beam position readings. The concept and its technical realization, as well as preliminary results of beam studies are presented.

  20. Design and implementation of spaceborne high resolution infrared touch screen

    NASA Astrophysics Data System (ADS)

    Li, Tai-guo; Li, Wen-xin; Dong, Yi-peng; Ma, Wen; Xia, Jia-gao

    2015-10-01

    For the consideration of the special application environment of the electronic products used in aerospace and to further more improve the human-computer interaction of the manned aerospace area. The research is based on the design and implementation way of the high resolution spaceborne infrared touch screen on the basis of FPGA and DSP frame structure. Beside the introduction of the whole structure for the high resolution spaceborne infrared touch screen system, this essay also gives the detail information about design of hardware for the high resolution spaceborne infrared touch screen system, FPGA design, GUI design and DSP algorithm design based on Lagrange interpolation. What is more, the easy makes a comprehensive research of the reliability design for the high resolution spaceborne infrared touch screen for the special purpose of it. Besides, the system test is done after installation of spaceborne infrared touch screen. The test result shows that the system is simple and reliable enough, which has a stable running environment and high resolution, which certainly can meet the special requirement of the manned aerospace instrument products.

  1. Ultra-thin wafer-level camera with 720p resolution using micro-optics

    NASA Astrophysics Data System (ADS)

    Brückner, Andreas; Oberdörster, Alexander; Dunkel, Jens; Reimann, Andreas; Müller, Martin; Wippermann, Frank

    2014-09-01

    We propose a microoptical approach to ultra-compact optics for real-time vision systems that are inspired by the compound eyes of insects. The demonstrated module achieves 720p resolution with a total track length of 2.0 mm which is about 1.5 times shorter than comparable conventional miniaturized optics. The partial images that are separately recorded in multiple optical channels are stitched together to form a final image of the whole FOV by means of image processing. The microlens arrays are realized by microoptical fabrication techniques on wafer-level which are suitable for a potential application in high volume e.g. for consumer electronic products.

  2. Lynx: A High-Resolution Synthetic Aperture Radar

    SciTech Connect

    Doerry, A.W.; Hensley, W.H.; Pace, F.; Stence, J.; Tsunoda, S.I.; Walker, B.C.; Woodring, M.

    1999-03-08

    Lynx is a high resolution, synthetic aperture radar (SAR) that has been designed and built by Sandia National Laboratories in collaboration with General Atomics (GA). Although Lynx may be operated on a wide variety of manned and unmanned platforms, it is primarily intended to be fielded on unmanned aerial vehicles. In particular, it may be operated on the Predator, I-GNAT, or Prowler II platforms manufactured by GA Aeronautical Systems, Inc. The Lynx production weight is less than 120 lb. and has a slant range of 30 km (in 4 mm/hr rain). It has operator selectable resolution and is capable of 0.1 m resolution in spotlight mode and 0.3 m resolution in stripmap mode. In ground moving target indicator mode, the minimum detectable velocity is 6 knots with a minimum target cross-section of 10 dBsm. In coherent change detection mode, Lynx makes registered, complex image comparisons either of 0.1 m resolution (minimum) spotlight images or of 0.3 m resolution (minimum) strip images. The Lynx user interface features a view manager that allows it to pan and zoom like a video camera. Lynx was developed under corporate finding from GA and will be manufactured by GA for both military and commercial applications. The Lynx system architecture will be presented and some of its unique features will be described. Imagery at the finest resolutions in both spotlight and strip modes have been obtained and will also be presented.

  3. High resolution X-ray spectroscopy using microcalorimeters

    NASA Technical Reports Server (NTRS)

    Kelley, R. L.; Holt, S. S.; Madejski, G. M.; Moseley, S. H.; Schoelkopf, R. J.; Szymkowiak, A. E.

    1988-01-01

    The use of microcalorimeters for high-resolution, high quantum efficiency, nondispersive X-ray spectroscopy has been demonstrated over the past few years. In this paper, the principles of X-ray calorimetry are reviewed, and the results of ongoing X-ray tests using microcalorimetry are summarized. An approach to building an X-ray calorimeter spectrometer is discussed.

  4. Quantification of upland thermokarst features with high resolution remote sensing

    NASA Astrophysics Data System (ADS)

    Belshe, E. F.; Schuur, E. A. G.; Grosse, G.

    2013-09-01

    Climate-induced changes to permafrost are altering high latitude landscapes in ways that could increase the vulnerability of the vast soil carbon pools of the region. Permafrost thaw is temporally dynamic and spatially heterogeneous because, in addition to the thickening of the active layer, localized thermokarst features form when ice-rich permafrost thaws and the ground subsides. Thermokarst produces a diversity of landforms and alters the physical environment in dynamic ways. To estimate potential changes to the carbon cycle it is imperative to quantify the size and distribution of thermokarst landforms. By performing a supervised classification on a high resolution IKONOS image, we detected and mapped small, irregular thermokarst features occurring within an upland watershed in discontinuous permafrost of Interior Alaska. We found that 12% of the Eight Mile Lake (EML) watershed has undergone thermokarst, predominantly in valleys where tussock tundra resides. About 35% of the 3.7 km2 tussock tundra class has likely transitioned to thermokarst. These landscape level changes created by permafrost thaw at EML have important implications for ecosystem carbon cycling because thermokarst features are forming in carbon-rich areas and are altering the hydrology in ways that increase seasonal thawing of the soil.

  5. High spectral resolution measurements for the ARM Program

    SciTech Connect

    Revercomb, H.E.

    1992-05-22

    This report focuses on the design and fabrication of high spectral resolution FTIR (Fourier Transform Infrared) instrumentation for the CART sites of the Atmospheric Radiation Measurement (ARM) Program. The ultimate objective of this grant is to develop three different types of instruments, named the AERI, AERI-X, and SORT. The Atmospheric Emitted Radiance Interferometer (AERI) is the simplest. It will be available for early deployment at the first ARM site and will be deployable at several locations in the extended network to give horizontal coverage. The AERI will be an 0.5 cm{sup {minus}1} resolution instrument, which measures accurately calibrated radiance spectra for radiation studies and for remote sensing of atmospheric state variables. The AERI-X and the SORTI are higher spectral resolution instruments for obtaining the highest practical resolution for spectroscopy at the ARM central sites. The AERI-X, like the AERI will measure atmospheric emitted radiance, but with resolutions as high as 0.1 cm{sup {minus}1}. The Solar Radiance Transmission Interferometer will measure the total transmission of the atmosphere by tracking the sun through changes in atmospheric air mass. The large solar signal makes it practical for this instrument to offer the ultimate in spectral resolution, about 0.002 cm{sup {minus}1}.

  6. High Resolution X-Ray Spectroscopy Using Microcalorimeters

    NASA Technical Reports Server (NTRS)

    Kelley, R. L.

    1997-01-01

    During the past 13 years high resolution X ray spectrometers have been developed that use cryogenically cooled microcalorimeters. These devices have inherently high signal-to-noise by operating at temperatures below 0.1 K and can achieve an energy resolution of < 10 eV over the 0.1-10 keV band. Existing devices use doped semiconductor thermometers and typically employ HgTe absorbers. The energy resolution depends on achieving a low heat capacity for the device. For soft X ray applications a relatively thin absorber (approximately 1 micrometer) may be used and an energy resolution of approximately 7 eV has been achieved. For applications up to approximately 10 keV an absorber thickness of approximately 10 micrometer is required and the energy resolution is typically approximately 12 eV. Improvements to the energy resolution in this energy band could be achieved if the problems of thermalizing X rays in low heat capacity superconductors can be overcome. The recent work on transition edge thermometers by Irwin et nl. looks particularly promising because of the higher sensitivity achievable from a sharp superconducting transition. The relatively low impedance of such a device permits the use of a low noise SQUID amplifier for readout. This would also significantly reduce the cryogen heat load compared with JFETs required by higher impedance semiconductor thermometers.

  7. High-resolution DEM Effects on Geophysical Flow Models

    NASA Astrophysics Data System (ADS)

    Williams, M. R.; Bursik, M. I.; Stefanescu, R. E. R.; Patra, A. K.

    2014-12-01

    Geophysical mass flow models are numerical models that approximate pyroclastic flow events and can be used to assess the volcanic hazards certain areas may face. One such model, TITAN2D, approximates granular-flow physics based on a depth-averaged analytical model using inputs of basal and internal friction, material volume at a coordinate point, and a GIS in the form of a digital elevation model (DEM). The volume of modeled material propagates over the DEM in a way that is governed by the slope and curvature of the DEM surface and the basal and internal friction angles. Results from TITAN2D are highly dependent upon the inputs to the model. Here we focus on a single input: the DEM, which can vary in resolution. High resolution DEMs are advantageous in that they contain more surface details than lower-resolution models, presumably allowing modeled flows to propagate in a way more true to the real surface. However, very high resolution DEMs can create undesirable artifacts in the slope and curvature that corrupt flow calculations. With high-resolution DEMs becoming more widely available and preferable for use, determining the point at which high resolution data is less advantageous compared to lower resolution data becomes important. We find that in cases of high resolution, integer-valued DEMs, very high-resolution is detrimental to good model outputs when moderate-to-low (<10-15°) slope angles are involved. At these slope angles, multiple adjacent DEM cell elevation values are equal due to the need for the DEM to approximate the low slope with a limited set of integer values for elevation. The first derivative of the elevation surface thus becomes zero. In these cases, flow propagation is inhibited by these spurious zero-slope conditions. Here we present evidence for this "terracing effect" from 1) a mathematically defined simulated elevation model, to demonstrate the terracing effects of integer valued data, and 2) a real-world DEM where terracing must be

  8. PANGU: A high resolution gamma-ray space telescope

    NASA Astrophysics Data System (ADS)

    Wu, Xin; Su, Meng; Bravar, Alessandro; Chang, Jin; Fan, Yizhong; Pohl, Martin; Walter, Roland

    2014-07-01

    We describe the instrument concept of a high angular resolution telescope dedicated to the sub-GeV (from >=10 MeV to >=1 GeV) gamma-ray photon detection. This mission, named PANGU (PAir-productioN Gamma-ray Unit), has been suggested as a candidate for the joint small mission between the European Space Agency (ESA) and the Chinese Academy of Science (CAS). A wide range of topics of both astronomy and fundamental physics can be attacked with PANGU, covering Galactic and extragalactic cosmic-ray physics, extreme physics of a variety of extended (e.g. supernova remnants, galaxies, galaxy clusters) and compact (e.g. black holes, pulsars, gamma-ray bursts) objects, solar and terrestrial gamma-ray phenomena, and searching for dark matter decay and/or annihilation signature etc. The unprecedented point spread function can be achieved with a pair-production telescope with a large number of thin active tracking layers to precisely reconstruct the pair-produced electron and positron tracks. Scintillating fibers or thin silicon micro-strip detectors are suitable technology for such a tracker. The energy measurement is achieved by measuring the momentum of the electrons and positrons through a magnetic field. The innovated spectrometer approach provides superior photon pointing resolution, and is particular suitable in the sub-GeV range. The level of tracking precision makes it possible to measure the polarization of gamma rays, which would open up a new frontier in gamma-ray astronomy. The frequent full-sky survey at sub-GeV with PANGU's large field of view and significantly improved point spread function would provide crucial information to GeV-TeV astrophysics for current/future missions including Fermi, DAMPE, HERD, and CTA, and other multi-wavelength telescopes.

  9. Achieving High Resolution Timer Events in Virtualized Environment.

    PubMed

    Adamczyk, Blazej; Chydzinski, Andrzej

    2015-01-01

    Virtual Machine Monitors (VMM) have become popular in different application areas. Some applications may require to generate the timer events with high resolution and precision. This however may be challenging due to the complexity of VMMs. In this paper we focus on the timer functionality provided by five different VMMs-Xen, KVM, Qemu, VirtualBox and VMWare. Firstly, we evaluate resolutions and precisions of their timer events. Apparently, provided resolutions and precisions are far too low for some applications (e.g. networking applications with the quality of service). Then, using Xen virtualization we demonstrate the improved timer design that greatly enhances both the resolution and precision of achieved timer events. PMID:26177366

  10. Achieving High Resolution Timer Events in Virtualized Environment

    PubMed Central

    Adamczyk, Blazej; Chydzinski, Andrzej

    2015-01-01

    Virtual Machine Monitors (VMM) have become popular in different application areas. Some applications may require to generate the timer events with high resolution and precision. This however may be challenging due to the complexity of VMMs. In this paper we focus on the timer functionality provided by five different VMMs—Xen, KVM, Qemu, VirtualBox and VMWare. Firstly, we evaluate resolutions and precisions of their timer events. Apparently, provided resolutions and precisions are far too low for some applications (e.g. networking applications with the quality of service). Then, using Xen virtualization we demonstrate the improved timer design that greatly enhances both the resolution and precision of achieved timer events. PMID:26177366

  11. Vehicle Detection and Classification from High Resolution Satellite Images

    NASA Astrophysics Data System (ADS)

    Abraham, L.; Sasikumar, M.

    2014-11-01

    In the past decades satellite imagery has been used successfully for weather forecasting, geographical and geological applications. Low resolution satellite images are sufficient for these sorts of applications. But the technological developments in the field of satellite imaging provide high resolution sensors which expands its field of application. Thus the High Resolution Satellite Imagery (HRSI) proved to be a suitable alternative to aerial photogrammetric data to provide a new data source for object detection. Since the traffic rates in developing countries are enormously increasing, vehicle detection from satellite data will be a better choice for automating such systems. In this work, a novel technique for vehicle detection from the images obtained from high resolution sensors is proposed. Though we are using high resolution images, vehicles are seen only as tiny spots, difficult to distinguish from the background. But we are able to obtain a detection rate not less than 0.9. Thereafter we classify the detected vehicles into cars and trucks and find the count of them.

  12. Adaptive optics high resolution spectroscopy: present status and future direction

    SciTech Connect

    Alcock, C; Angel, R; Ciarlo, D; Fugate, R O; Ge, J; Kuzmenko, P; Lloyd-Hart, M; Macintosh, B; Najita, J; Woolf, N

    1999-07-27

    High resolution spectroscopy experiments with visible adaptive optics (AO) telescopes at Starfire Optical Range and Mt. Wilson have demonstrated that spectral resolution can be routinely improved by a factor of - 10 over the seeing-limited case with no extra light losses at visible wavelengths. With large CCDs now available, a very wide wavelength range can be covered in a single exposure. In the near future, most large ground-based telescopes will be equipped with powerful A0 systems. Most of these systems are aimed primarily at diffraction-limited operation in the near IR. An exciting new opportunity will thus open up for high resolution IR spectroscopy. Immersion echelle gratings with much coarser grooves being developed by us at LLNL will play a critical role in achieving high spectral resolution with a compact and low cost IR cryogenically cooled spectrograph and simultaneous large wavelength coverage on relatively small IR detectors. We have constructed a new A0 optimized spectrograph at Steward Observatory to provide R = 200,000 in the optical, which is being commissioned at the Starfire Optical Range 3.5m telescope. We have completed the optical design of the LLNL IR Immersion Spectrograph (LISPEC) to take advantage of improved silicon etching technology. Key words: adaptive optics, spectroscopy, high resolution, immersion gratings

  13. High Resolution SPectrometer for HCT, Hanle: an update

    NASA Astrophysics Data System (ADS)

    Sunetra, Giridhar; Sivarani, T.; Anantha, Ch.; Jayashree, Roy; Anand, M. N.; Anupama, G. C.; Mahesh, P. K.; Parihar, P. S.; Prabhu, T. P.; Singhal, A. K.; Sriram, S.; Sundararajan, M. S.

    A high resolution spectrometer for the 2m Himalayan Chandra Telescope (HCT) at Indian Astronomical Observatory (IAO) Hanle, is being built to meet the observational requirement of many advanced areas in astronomy requiring high spectral resolution. This instrument is based upon a modern design using a white pupil concept which has been adopted in several contemporary high resolution spectrometers. This design is known to reduce light losses due to vignetting and also provides the full spectral coverage (350nm-1000nm) in a single CCD frame. This design also incorporates additional features like image-slicer which would result in very high light efficiency. A peak throughput of 20% in visual range and throughput of 8% is expected at extreme blue and red wavelengths. The spectrometer would give resolutions of 60,000 and 30,000 in two resolution modes. In this contribution we describe the instrument and its environment and give an update on its development and science programs we propose to undertake.

  14. New vacuum solar telescope and observations with high resolution

    NASA Astrophysics Data System (ADS)

    Liu, Zhong; Xu, Jun; Gu, Bo-Zhong; Wang, Sen; You, Jian-Qi; Shen, Long-Xiang; Lu, Ru-Wei; Jin, Zhen-Yu; Chen, Lin-Fei; Lou, Ke; Li, Zhi; Liu, Guang-Qian; Xu, Zhi; Rao, Chang-Hui; Hu, Qi-Qian; Li, Ru-Feng; Fu, Hao-Wen; Wang, Feng; Bao, Men-Xian; Wu, Ming-Chan; Zhang, Bo-Rong

    2014-06-01

    The New Vacuum Solar Telescope (NVST) is a one meter vacuum solar telescope that aims to observe fine structures on the Sun. The main goals of NVST are high resolution imaging and spectral observations, including measurements of the solar magnetic field. NVST is the primary ground-based facility used by the Chinese solar research community in this solar cycle. It is located by Fuxian Lake in southwest China, where the seeing is good enough to perform high resolution observations. We first introduce the general conditions at the Fuxian Solar Observatory and the primary science cases of NVST. Then, the basic structures of this telescope and instruments are described in detail. Finally, some typical high resolution data of the solar photosphere and chromosphere are also shown.

  15. High spatial resolution measurements of ram accelerator gas dynamic phenomena

    NASA Technical Reports Server (NTRS)

    Hinkey, J. B.; Burnham, E. A.; Bruckner, A. P.

    1992-01-01

    High spatial resolution experimental tube wall pressure measurements of ram accelerator gas dynamic phenomena are presented. The projectile resembles the centerbody of a ramjet and travels supersonically through a tube filled with a combustible gaseous mixture, with the tube acting as the outer cowling. Pressure data are recorded as the projectile passes by sensors mounted in the tube wall at various locations along the tube. Data obtained by using a special highly instrumented section of tube has allowed the recording of gas dynamic phenomena with a spatial resolution on the order of one tenth the projectile length. High spatial resolution tube wall pressure data from the three regimes of propulsion studied to date (subdetonative, transdetonative, and superdetonative) are presented and reveal the 3D character of the flowfield induced by projectile fins and the canting of the projectile body relative to the tube wall. Also presented for comparison to the experimental data are calculations made with an inviscid, 3D CFD code.

  16. High-resolution adaptive optics test bed for vision science

    NASA Astrophysics Data System (ADS)

    Wilks, Scott C.; Thompson, Charles A.; Olivier, Scot S.; Bauman, Brian J.; Flath, Laurence M.; Silva, Dennis A.; Sawvel, Robert M.; Barnes, Thomas B.; Werner, John S.

    2002-02-01

    We discuss the design and implementation of a low-cost, high-resolution adaptive optics test-bed for vision research. It is well known that high-order aberrations in the human eye reduce optical resolution and limit visual acuity. However, the effects of aberration-free eyesight on vision are only now beginning to be studied using adaptive optics to sense and correct the aberrations in the eye. We are developing a high-resolution adaptive optics system for this purpose using a Hamamatsu Parallel Aligned Nematic Liquid Crystal Spatial Light Modulator. Phase-wrapping is used to extend the effective stroke of the device, and the wavefront sensing and wavefront correction are done at different wavelengths. Issues associated with these techniques will be discussed.

  17. High-resolution streaming video integrated with UGS systems

    NASA Astrophysics Data System (ADS)

    Rohrer, Matthew

    2010-04-01

    Imagery has proven to be a valuable complement to Unattended Ground Sensor (UGS) systems. It provides ultimate verification of the nature of detected targets. However, due to the power, bandwidth, and technological limitations inherent to UGS, sacrifices have been made to the imagery portion of such systems. The result is that these systems produce lower resolution images in small quantities. Currently, a high resolution, wireless imaging system is being developed to bring megapixel, streaming video to remote locations to operate in concert with UGS. This paper will provide an overview of how using Wifi radios, new image based Digital Signal Processors (DSP) running advanced target detection algorithms, and high resolution cameras gives the user an opportunity to take high-powered video imagers to areas where power conservation is a necessity.

  18. A high-resolution ambient seismic noise model for Europe

    NASA Astrophysics Data System (ADS)

    Kraft, Toni

    2014-05-01

    measurement precision (i.e. earthquake location), while considering this extremely complex boundary condition. To solve this problem I have developed a high-resolution ambient seismic noise model for Europe. The model is based on land-use data derived from satellite imagery by the EU-project CORINE in a resolution of 100x100m. The the CORINE data consists of several land-use classes, which, besides others, contain: industrial areas, mines, urban fabric, agricultural areas, permanent corps, forests and open spaces. Additionally, open GIS data for highways, and major and minor roads and railway lines were included from the OpenStreetMap project (www.openstreetmap.org). This data was divided into three classes that represent good, intermediate and bad ambient conditions of the corresponding land-use class based on expert judgment. To account for noise propagation away from its source a smoothing operator was applied to individual land-use noise-fields. Finally, the noise-fields were stacked to obtain an European map of ambient noise conditions. A calibration of this map with data of existing seismic stations Europe allowed me to estimate the expected noise level in actual ground motion units for the three ambient noise condition classes of the map. The result is a high-resolution ambient seismic noise map, that allows the network designer to make educated predictions on the expected noise level for arbitrary location in Europe. The ambient noise model was successfully tested in several network optimization projects in Switzerland and surrounding countries and will hopefully be a valuable contribution to improving the data quality of microseismic monitoring networks in Europe.

  19. High resolution collimator system for X-ray detector

    DOEpatents

    Eberhard, Jeffrey W.; Cain, Dallas E.

    1987-01-01

    High resolution in an X-ray computerized tomography (CT) inspection system is achieved by using a collimator/detector combination to limit the beam width of the X-ray beam incident on a detector element to the desired resolution width. In a detector such as a high pressure Xenon detector array, a narrow tapered collimator is provided above a wide detector element. The collimator slits have any desired width, as small as a few mils at the top, the slit width is easily controlled, and they are fabricated on standard machines. The slit length determines the slice thickness of the CT image.

  20. HIRES: the high resolution spectrograph for the E-ELT

    NASA Astrophysics Data System (ADS)

    Zerbi, F. M.; Bouchy, F.; Fynbo, J.; Maiolino, R.; Piskunov, N.; Rebolo Lopez, R.; Santos, N.; Strassmeier, K.; Udry, S.; Vanzi, L.; Riva, M.; Basden, A.; Boisse, I.; Bonfils, X.; Buscher, D.; Cabral, A.; Dimarcantonio, P.; Di Varano, I.; Henry, D.; Monteiro, M.; Morris, T.; Murray, G.; Oliva, Ernesto; Parry, I.; Pepe, F.; Quirrenbach, A.; Rasilla, J. L.; Rees, P.; Stempels, E.; Valenziano, L.; Wells, M.; Wildi, F.; Origlia, L.; Allende Prieto, C.; Chiavassa, A.; Cristiani, S.; Figueira, P.; Gustafsson, B.; Hatzes, A.; Haehnelt, M.; Heng, K.; Israelian, G.; Kochukhov, O.; Lovis, C.; Marconi, A.; Martins, C. J. A. P.; Noterdaeme, P.; Petitjean, P.; Puzia, T.; Queloz, D.; Reiners, A.; Zoccali, M.

    2014-08-01

    The current instrumentation plan for the E-ELT foresees a High Resolution Spectrograph conventionally indicated as HIRES. Shaped on the study of extra-solar planet atmospheres, Pop-III stars and fundamental physical constants, HIRES is intended to embed observing modes at high-resolution (up to R=150000) and large spectral range (from the blue limit to the K band) useful for a large suite of science cases that can exclusively be tackled by the E-ELT. We present in this paper the solution for HIRES envisaged by the "HIRES initiative", the international collaboration established in 2013 to pursue a HIRES on E-ELT.

  1. High resolution X-ray spectroscopy of active galactic nuclei

    NASA Technical Reports Server (NTRS)

    Krolik, Julian H.

    1990-01-01

    After a brief review of the principal problems of AGN research, selected potential high-resolution observations are discussed with a view toward assessing their scientific value and the degree of resolution they will require. Two classes of observations pertaining directly to AGNs are discussed. Fe K-alpha spectroscopy relevant to the dynamical and thermal character of the emission line zones; and measurement of resonance line absorption by highly-ionized species in BL Lac objects, which should provide information about entrainment of interstellar material by relativistic jets. A third class of potentially important observations uses AGNs as background light sources in order to directly measure the distance to clusters of galaxies.

  2. Design of high-resolution grazing-incidence echelle monochromators

    SciTech Connect

    Poletto, Luca; Frassetto, Fabio

    2009-10-01

    A grazing-incidence configuration to achieve high spectral resolution in the extreme ultraviolet and soft x-ray regions is presented. It adopts a grating in the off-plane mount operated at high diffracted orders. Resolutions in the 10{sup 5} range can be achieved in a relatively compact size. The monochromator can be tuned in a complete octave by using different diffracted orders without changing the geometrical parameters of the configuration. The optical design of the configuration and the application to a beamline for free-electron-laser radiation centered at 120 eV are discussed.

  3. Theoretical Problems in High Resolution Solar Physics, 2

    NASA Technical Reports Server (NTRS)

    Athay, G. (Editor); Spicer, D. S. (Editor)

    1987-01-01

    The Science Working Group for the High Resolution Solar Observatory (HRSO) laid plans beginning in 1984 for a series of workshops designed to stimulate a broadbased input from the scientific community to the HRSO mission. These workshops have the dual objectives of encouraging an early start on the difficult theoretical problems in radiative transfer, magnetohydrodynamics, and plasma physics that will be posed by the HRSO data, and maintaining current discussions of results in high resolution solar studies. This workshop was the second in the series. The workshop format presented invited review papers during the formal sessions and contributed poster papers for discussions during open periods. Both are presented.

  4. Exploring NASA Satellite Data with High Resolution Visualization

    NASA Astrophysics Data System (ADS)

    Wei, J. C.; Yang, W.; Johnson, J. E.; Shen, S.; Zhao, P.; Gerasimov, I. V.; Vollmer, B.; Vicente, G. A.; Pham, L.

    2013-12-01

    Satellite data products are important for a wide variety of applications that can bring far-reaching benefits to the science community and the broader society. These benefits can best be achieved if the satellite data are well utilized and interpreted, such as model inputs from satellite, or extreme event (such as volcano eruption, dust storm, ...etc) interpretation from satellite. Unfortunately, this is not always the case, despite the abundance and relative maturity of numerous satellite data products provided by NASA and other organizations. Such obstacles may be avoided by providing satellite data as ';Images' with accurate pixel-level (Level 2) information, including pixel coverage area delineation and science team recommended quality screening for individual geophysical parameters. We will present a prototype service from the Goddard Earth Sciences Data and Information Services Center (GES DISC) supporting various visualization and data accessing capabilities from satellite Level 2 data (non-aggregated and un-gridded) at high spatial resolution. Functionality will include selecting data sources (e.g., multiple parameters under the same measurement, like NO2 and SO2 from Ozone Monitoring Instrument (OMI), or same parameter with different methods of aggregation, like NO2 in OMNO2G and OMNO2D products), defining area-of-interest and temporal extents, zooming, panning, overlaying, sliding, and data subsetting and reformatting. The portal interface will connect to the backend services with OGC standard-compliant Web Mapping Service (WMS) and Web Coverage Service (WCS) calls. The interface will also be able to connect to other OGC WMS and WCS servers, which will greatly enhance its expandability to integrate additional outside data/map sources.

  5. High-resolution subsurface water-ice distributions on Mars.

    PubMed

    Bandfield, Joshua L

    2007-05-01

    Theoretical models indicate that water ice is stable in the shallow subsurface (depths of <1-2 m) of Mars at high latitudes. These models have been mainly supported by the observed presence of large concentrations of hydrogen detected by the Gamma Ray Spectrometer suite of instruments on the Mars Odyssey spacecraft. The models and measurements are consistent with a water-ice table that steadily increases in depth with decreasing latitude. More detailed modelling has predicted that the depth at which water ice is stable can be highly variable, owing to local surface heterogeneities such as rocks and slopes, and the thermal inertia of the ground cover. Measurements have, however, been limited to the footprint (several hundred kilometres) of the Gamma Ray Spectrometer suite, preventing the observations from documenting more detailed water-ice distributions. Here I show that by observing the seasonal temperature response of the martian surface with the Thermal Emission Imaging System on the Mars Odyssey spacecraft, it is possible to observe such heterogeneities at subkilometre scale. These observations show significant regional and local water-ice depth variability, and, in some cases, support distributions in the subsurface predicted by atmospheric exchange and vapour diffusion models. The presence of water ice where it follows the depth of stability under current climatic conditions implies an active martian water cycle that responds to orbit-driven climate cycles. Several regions also have apparent deviations from the theoretical stability level, indicating that additional factors influence the ice-table depth. The high-resolution measurements show that the depth to the water-ice table is highly variable within the potential Phoenix spacecraft landing ellipses, and is likely to be variable at scales that may be sampled by the spacecraft. PMID:17476262

  6. High resolution interferometer with multiple-pass optical configuration.

    PubMed

    Ahn, Jeongho; Kim, Jong-Ahn; Kang, Chu-Shik; Kim, Jae-Wan; Kim, Soohyun

    2009-11-01

    An interferometer having fourteen times higher resolution than a conventional single-pass interferometer has been developed by making multiple-pass optical path. To embody the multiple-pass optical configuration, a two-dimensional corner cube array block was designed, and its symmetric structure minimized the measurement error. The effect from the alignment error and the imperfection of corner cube is calculated as picometer level. An experiment proves that the suggested interferometer has about 45 nm of optical resolution and its nonlinearity is about 0.5 nm in peak-to-valley. PMID:19997342

  7. Progress in high-resolution x-ray holographic microscopy

    SciTech Connect

    Jacobsen, C.; Kirz, J.; Howells, M.; McQuaid, K.; Rothman, S.; Feder, R.; Sayre, D.

    1987-07-01

    Among the various types of x-ray microscopes that have been demonstrated, the holographic microscope has had the largest gap between promise and performance. The difficulties of fabricating x-ray optical elements have led some to view holography as the most attractive method for obtaining the ultimate in high resolution x-ray micrographs; however, we know of no investigations prior to 1987 that clearly demonstrated submicron resolution in reconstructed images. Previous efforts suffered from problems such as limited resolution and dynamic range in the recording media, low coherent x-ray flux, and aberrations and diffraction limits in visible light reconstruction. We have addressed the recording limitations through the use of an undulator x-ray source and high-resolution photoresist recording media. For improved results in the readout and reconstruction steps, we have employed metal shadowing and transmission electron microscopy, along with numerical reconstruction techniques. We believe that this approach will allow holography to emerge as a practical method of high-resolution x-ray microscopy. 30 refs., 4 figs.

  8. Wide-field, high-resolution Fourier ptychographic microscopy

    PubMed Central

    Zheng, Guoan; Horstmeyer, Roarke; Yang, Changhuei

    2014-01-01

    In this article, we report an imaging method, termed Fourier ptychographic microscopy (FPM), which iteratively stitches together a number of variably illuminated, low-resolution intensity images in Fourier space to produce a wide-field, high-resolution complex sample image. By adopting a wavefront correction strategy, the FPM method can also correct for aberrations and digitally extend a microscope’s depth-of-focus beyond the physical limitations of its optics. As a demonstration, we built a microscope prototype with a resolution of 0.78 μm, a field-of-view of ~120 mm2, and a resolution-invariant depth-of-focus of 0.3 mm (characterized at 632 nm). Gigapixel colour images of histology slides verify FPM’s successful operation. The reported imaging procedure transforms the general challenge of high-throughput, high-resolution microscopy from one that is coupled to the physical limitations of the system’s optics to one that is solvable through computation. PMID:25243016

  9. High-resolution EEG (HR-EEG) and magnetoencephalography (MEG).

    PubMed

    Gavaret, M; Maillard, L; Jung, J

    2015-03-01

    High-resolution EEG (HR-EEG) and magnetoencephalography (MEG) allow the recording of spontaneous or evoked electromagnetic brain activity with excellent temporal resolution. Data must be recorded with high temporal resolution (sampling rate) and high spatial resolution (number of channels). Data analyses are based on several steps with selection of electromagnetic signals, elaboration of a head model and use of algorithms in order to solve the inverse problem. Due to considerable technical advances in spatial resolution, these tools now represent real methods of ElectroMagnetic Source Imaging. HR-EEG and MEG constitute non-invasive and complementary examinations, characterized by distinct sensitivities according to the location and orientation of intracerebral generators. In the presurgical assessment of drug-resistant partial epilepsies, HR-EEG and MEG can characterize and localize interictal activities and thus the irritative zone. HR-EEG and MEG often yield significant additional data that are complementary to other presurgical investigations and particularly relevant in MRI-negative cases. Currently, the determination of the epileptogenic zone and functional brain mapping remain rather less well-validated indications. In France, in 2014, HR-EEG is now part of standard clinical investigation of epilepsy, while MEG remains a research technique. PMID:25648821

  10. High temperature liquid level sensor

    DOEpatents

    Tokarz, Richard D.

    1983-01-01

    A length of metal sheathed metal oxide cable is perforated to permit liquid access to the insulation about a pair of conductors spaced close to one another. Changes in resistance across the conductors will be a function of liquid level, since the wetted insulation will have greater electrical conductivity than that of the dry insulation above the liquid elevation.

  11. Contrast transfer and resolution limits for sub-angstrom high-resolution transmission electron microscopy.

    PubMed

    Lentzen, Markus

    2008-02-01

    The optimum imaging of an object structure at the sub-angstrom length scale requires precise adjustment of the lens aberrations of a high-resolution instrument up to the fifth order. A least-squares optimization of defocus aberration C1, third-order spherical aberration C3, and fifth-order spherical aberration C5 yields two sets of aberration coefficients for strong phase contrast up to the information limit: one for variable C1 and C3, at fixed C5, another for variable C1, C3, and C5. An additional correction to the defocus aberration, dependent on object thickness, is described, which becomes important for the use of image simulation programs in predicting optimum high-resolution contrast from thin objects at the sub-angstrom scale. For instruments with a sub-angstrom information limit the ultimate structure resolution, the power to resolve adjacent atom columns in a crystalline object, depends on both the instrumental pointspread and an object pointspread due to finite width of the atomic column potentials. A simulation study on a simple double-column model yields a range for structure resolutions, dependent on the atomic scattering power, from 0.070 nm down to 0.059 nm, for a hypothetical 300-kV instrument with an information limit of 0.050 nm. PMID:18096097

  12. Multi-resolution voxel phantom modeling: a high-resolution eye model for computational dosimetry

    NASA Astrophysics Data System (ADS)

    Caracappa, Peter F.; Rhodes, Ashley; Fiedler, Derek

    2014-09-01

    Voxel models of the human body are commonly used for simulating radiation dose with a Monte Carlo radiation transport code. Due to memory limitations, the voxel resolution of these computational phantoms is typically too large to accurately represent the dimensions of small features such as the eye. Recently reduced recommended dose limits to the lens of the eye, which is a radiosensitive tissue with a significant concern for cataract formation, has lent increased importance to understanding the dose to this tissue. A high-resolution eye model is constructed using physiological data for the dimensions of radiosensitive tissues, and combined with an existing set of whole-body models to form a multi-resolution voxel phantom, which is used with the MCNPX code to calculate radiation dose from various exposure types. This phantom provides an accurate representation of the radiation transport through the structures of the eye. Two alternate methods of including a high-resolution eye model within an existing whole-body model are developed. The accuracy and performance of each method is compared against existing computational phantoms.

  13. New Challenges in High-Resolution Modeling of Hurricanes

    NASA Astrophysics Data System (ADS)

    Chen, S. S.

    2006-12-01

    The extreme active Atlantic hurricane seasons in recent years have highlighted the urgent need for a better understanding of the factors that contribute to hurricane intensity and for development of the corresponding advanced hurricane prediction models to improve intensity forecasts. The lack of skill in present forecasts of hurricane structure and intensity may be attributed in part to deficiencies in the current prediction models: insufficient grid resolution, inadequate surface and boundary layer formulations, and the lack of full coupling to a dynamic ocean. The extreme high winds, intense rainfall, large ocean waves, and copious sea spray in hurricanes push the surface-exchange parameters for temperature, water vapor, and momentum into untested regimes. The recent modeling effort is to develop and test a fully coupled atmosphere-wave-ocean modeling system that is capable of resolving the eye and eyewall in a hurricane at ~1 km grid resolution. The new challenges for these very high resolution models are the corresponding physical representations at 1-km scale, including microphysics, sub-grid turbulence parameterization, atmospheric boundary layer, physical processes at the air-sea interface with surface waves among others. The lack of accurate initial conditions for high-resolution hurricane modeling presents another major challenge. Improvements in initial conditions rest on the use of more airborne and remotely sensed observations in high-resolution assimilation systems and on the application of advanced assimilation schemes to hurricanes. This study aimed to provide an overview of these new challenges using high-resolution model simulations of Hurricanes Isabel (2003), Frances (2004), Katrina and Rita (2005) that were observed extensively by two recent field programs, namely, the Coupled Boundary Layer Air-Sea Transfer (CBLAST)-Hurricane in 2003-2004 and the Hurricane Rainbands and Intensity Change Experiment (RAINEX) in 2005.

  14. High-resolution lensless Fourier transform holography for microstructure imaging

    NASA Astrophysics Data System (ADS)

    Zhao, Jie; Wang, Dayong; Wang, Huaying; Xie, Jianjun

    2007-12-01

    Digital holography combines the advantages of the optical holography and the computers. It can implement an all-digital processing and has the quasi real-time property. With lensless Fourier transform recording architecture, the limited bandwidth of CCD camera can be utilized sufficiently, and the sampling theorem is satisfied easily. Therefore, high-resolution can be achieved. So it is preferred in the microstructure imaging. In the paper, based on the Fresnel diffraction theory and the off-axis lensless Fourier transform recording architecture, the experimental optimization and correspondingly the digital reconstruction was investigated. Also, the lateral resolution of the reconstructed image was analyzed and improved by the proposed techniques. When the USAF test target was imaged without any pre-magnification, the lateral resolution of 3.1μm was achieved, which matched the theoretical prediction very well. The key points to achieve high resolution image are to use the smaller object and to arrange the distance between the object and the CCD plane as short as possible. Meanwhile, properly overlapping the reconstructed image with the DC term was helpful to improve the resolution. The noise in the reconstructed image could be reduced greatly by choosing the optical elements precisely and adjusting the beam path finely. The experimental results demonstrated that it is possible for the digital holographic microscopy to produce the high resolution image without the objective pre-magnification. The results also showed that, with a high quality hologram, the special image processing during the reconstruction may be unnecessary to obtain a high quality image.

  15. High-resolution harmonic motion imaging (HR-HMI) for tissue biomechanical property characterization

    PubMed Central

    Ma, Teng; Qian, Xuejun; Chiu, Chi Tat; Yu, Mingyue; Jung, Hayong; Tung, Yao-Sheng; Shung, K. Kirk

    2015-01-01

    Background Elastography, capable of mapping the biomechanical properties of biological tissues, serves as a useful technique for clinicians to perform disease diagnosis and determine stages of many diseases. Many acoustic radiation force (ARF) based elastography, including acoustic radiation force impulse (ARFI) imaging and harmonic motion imaging (HMI), have been developed to remotely assess the elastic properties of tissues. However, due to the lower operating frequencies of these approaches, their spatial resolutions are insufficient for revealing stiffness distribution on small scale applications, such as cancerous tumor margin detection, atherosclerotic plaque composition analysis and ophthalmologic tissue characterization. Though recently developed ARF-based optical coherence elastography (OCE) methods open a new window for the high resolution elastography, shallow imaging depths significantly limit their usefulness in clinics. Methods The aim of this study is to develop a high-resolution HMI method to assess the tissue biomechanical properties with acceptable field of view (FOV) using a 4 MHz ring transducer for efficient excitation and a 40 MHz needle transducer for accurate detection. Under precise alignment of two confocal transducers, the high-resolution HMI system has a lateral resolution of 314 µm and an axial resolution of 
147 µm with an effective FOV of 2 mm in depth. Results The performance of this high resolution imaging system was validated on the agar-based tissue mimicking phantoms with different stiffness distributions. These data demonstrated the imaging system’s improved resolution and sensitivity on differentiating materials with varying stiffness. In addition, ex vivo imaging of a human atherosclerosis coronary artery demonstrated the capability of high resolution HMI in identifying layer-specific structures and characterizing atherosclerotic plaques based on their stiffness differences. Conclusions All together high resolution HMI

  16. Special issue on high-resolution optical imaging

    NASA Astrophysics Data System (ADS)

    Smith, Peter J. S.; Davis, Ilan; Galbraith, Catherine G.; Stemmer, Andreas

    2013-09-01

    The pace of development in the field of advanced microscopy is truly breath-taking, and is leading to major breakthroughs in our understanding of molecular machines and cell function. This special issue of Journal of Optics draws attention to a number of interesting approaches, ranging from fluorescence and imaging of unlabelled cells, to computational methods, all of which are describing the ever increasing detail of the dynamic behaviour of molecules in the living cell. This is a field which traditionally, and currently, demonstrates a marvellous interplay between the disciplines of physics, chemistry and biology, where apparent boundaries to resolution dissolve and living cells are viewed in ever more clarity. It is fertile ground for those interested in optics and non-conventional imaging to contribute high-impact outputs in the fields of cell biology and biomedicine. The series of articles presented here has been selected to demonstrate this interdisciplinarity and to encourage all those with a background in the physical sciences to 'dip their toes' into the exciting and dynamic discoveries surrounding cell function. Although single molecule super-resolution microscopy is commercially available, specimen preparation and interpretation of single molecule data remain a major challenge for scientists wanting to adopt the techniques. The paper by Allen and Davidson [1] provides a much needed detailed introduction to the practical aspects of stochastic optical reconstruction microscopy, including sample preparation, image acquisition and image analysis, as well as a brief description of the different variants of single molecule localization microscopy. Since super-resolution microscopy is no longer restricted to three-dimensional imaging of fixed samples, the review by Fiolka [2] is a timely introduction to techniques that have been successfully applied to four-dimensional live cell super-resolution microscopy. The combination of multiple high-resolution techniques

  17. High Resolution Simulations of Future Climate in West Africa Using a Variable-Resolution Atmospheric Model

    NASA Astrophysics Data System (ADS)

    Adegoke, J. O.; Engelbrecht, F.; Vezhapparambu, S.

    2013-12-01

    In previous work demonstrated the application of a var¬iable-resolution global atmospheric model, the conformal-cubic atmospheric model (CCAM), across a wide range of spatial and time scales to investigate the ability of the model to provide realistic simulations of present-day climate and plausible projections of future climate change over sub-Saharan Africa. By applying the model in stretched-grid mode the versatility of the model dynamics, numerical formulation and physical parameterizations to function across a range of length scales over the region of interest, was also explored. We primarily used CCAM to illustrate the capability of the model to function as a flexible downscaling tool at the climate-change time scale. Here we report on additional long term climate projection studies performed by downscaling at much higher resolutions (8 Km) over an area that stretches from just south of Sahara desert to the southern coast of the Niger Delta and into the Gulf of Guinea. To perform these simulations, CCAM was provided with synoptic-scale forcing of atmospheric circulation from 2.5 deg resolution NCEP reanalysis at 6-hourly interval and SSTs from NCEP reanalysis data uses as lower boundary forcing. CCAM 60 Km resolution downscaled to 8 Km (Schmidt factor 24.75) then 8 Km resolution simulation downscaled to 1 Km (Schmidt factor 200) over an area approximately 50 Km x 50 Km in the southern Lake Chad Basin (LCB). Our intent in conducting these high resolution model runs was to obtain a deeper understanding of linkages between the projected future climate and the hydrological processes that control the surface water regime in this part of sub-Saharan Africa.

  18. High temporal resolution for multislice helical computed tomography.

    PubMed

    Taguchi, K; Anno, H

    2000-05-01

    Multislice helical computed tomography (CT) substantially reduces scanning time. However, the temporal resolution of individual images is still insufficient for imaging rapidly moving organs such as the heart and adjacent pulmonary vessels. It may, in some cases, be worse than with current single-slice helical CT. The purpose of this study is to describe a novel image reconstruction algorithm to improve temporal resolution in multislice helical CT, and to evaluate its performance against existing algorithms. The proposed image reconstruction algorithm uses helical interpolation followed by data weighting based on the acquisition time. The temporal resolution, the longitudinal (z-axis) spatial resolution, the image noise, and the in-plane image artifacts created by a moving phantom were compared with those from the basic multislice helical reconstruction (helical filter interpolation, HFI) algorithm and the basic single-slice helical reconstruction algorithm (180 degrees linear interpolation, 180LI) using computer simulations. Computer simulation results were verified with CT examinations of the heart and lung vasculature using a 0.5 second multislice scanner. The temporal resolution of HFI algorithm varies from 0.28 and 0.86 s, depending on helical pitch. The proposed method improves the resolution to a constant value of 0.29 s, independent of pitch, allowing moving objects to be imaged with reduced blurring or motion artifacts. The spatial (z) resolution was slightly worse than with the HFI algorithm; the image noise was worse than with the HFI algorithm but was comparable to axial (step-and-shoot) CT. The proposed method provided sharp images of the moving objects, portraying the anatomy accurately. The proposed algorithm for multislice helical CT allowed us to obtain CT images with high temporal resolution. It may improve the image quality of clinical cardiac, lung, and vascular CT imaging. PMID:10841388

  19. High Resolution Coherent Three-Dimensional Spectroscopy of Iodine

    NASA Astrophysics Data System (ADS)

    House, Zuri R.; Wells, Thresa A.; Chen, Peter C.; Strangfeld, Benjamin R.

    2013-06-01

    The heavy congestion found in many one-dimensional spectra can make it difficult to study many transitions. A new coherent three-dimensional spectroscopic technique has been developed to eliminate the kind of congestion commonly seen in high resolution electronic spectra. The molecule used for this test was Iodine. A well-characterized transition (X to B) was used to determine which four wave mixing process or processes were responsible for the peaks in the resulting multidimensional spectrum. The resolution of several peaks that overlap in a coherent 2D spectrum can be accomplished by using a higher dimensional (3D) spectroscopic method. This talk will discuss strategies for finding spectroscopic constants using this high resolution coherent 3D spectroscopic method.

  20. An Introduction to High Resolution Coherent Multidimensional Spectroscopy

    NASA Astrophysics Data System (ADS)

    Chen, Peter C.; Wells, Thresa A.; House, Zuri R.; Strangfeld, Benjamin R.

    2013-06-01

    High resolution coherent multidimensional spectroscopy is a technique that can be used to analyze and assign peaks for molecules that have resisted spectral analysis. Molecules that yield heavily congested and seemingly patternless spectra using conventional methods can yield 2D spectra that have recognizable patterns. The off-diagonal region of the coherent 2D plot shows only cross-peaks that are related by rotational selection rules. The resulting patterns facilitate peak assignment if they are sufficiently resolved. For systems that are not well-resolved, coherent 3D spectra may be generated to further improve resolution and provide selectivity. This presentation will provide an introduction to high resolution coherent 2D and 3D spectroscopies.