Improved Thermal-Vacuum Compatible Flat Plate Radiometric Souce for System-Level Testing of Optical Sensors

NASA Technical Reports Server (NTRS)

Schwarz, Mark A.; Kent, Craig J.; Bousquet, Robert; Brown, Steven W.

2015-01-01

This work describes the development of an improved vacuum compatible flat plate radiometric source used for characterizing and calibrating remote optical sensors, in situ, throughout their testing period. The original flat plate radiometric source was developed for use by the VIIRS instrument during the NPOESS Preparatory Project (NPP). Following this effort, the FPI has had significant upgrades in order to improve both the radiometric throughput and uniformity. Results of the VIIRS testing with the reconfigured FPI are reported and discussed.

Pre-Flight Radiometric Model of Linear Imager on LAPAN-IPB Satellite

NASA Astrophysics Data System (ADS)

Hadi Syafrudin, A.; Salaswati, Sartika; Hasbi, Wahyudi

2018-05-01

LAPAN-IPB Satellite is Microsatellite class with mission of remote sensing experiment. This satellite carrying Multispectral Line Imager for captured of radiometric reflectance value from earth to space. Radiometric quality of image is important factor to classification object on remote sensing process. Before satellite launch in orbit or pre-flight, Line Imager have been tested by Monochromator and integrating sphere to get spectral and every pixel radiometric response characteristic. Pre-flight test data with variety setting of line imager instrument used to see correlation radiance input and digital number of images output. Output input correlation is described by the radiance conversion model with imager setting and radiometric characteristics. Modelling process from hardware level until normalize radiance formula are presented and discussed in this paper.

The Landsat Data Continuity Mission Operational Land Imager (OLI) Radiometric Calibration

NASA Technical Reports Server (NTRS)

Markham, Brian L.; Dabney, Philip W.; Murphy-Morris, Jeanine E.; Knight, Edward J.; Kvaran, Geir; Barsi, Julia A.

2010-01-01

The Operational Land Imager (OLI) on the Landsat Data Continuity Mission (LDCM) has a comprehensive radiometric characterization and calibration program beginning with the instrument design, and extending through integration and test, on-orbit operations and science data processing. Key instrument design features for radiometric calibration include dual solar diffusers and multi-lamped on-board calibrators. The radiometric calibration transfer procedure from NIST standards has multiple checks on the radiometric scale throughout the process and uses a heliostat as part of the transfer to orbit of the radiometric calibration. On-orbit lunar imaging will be used to track the instruments stability and side slither maneuvers will be used in addition to the solar diffuser to flat field across the thousands of detectors per band. A Calibration Validation Team is continuously involved in the process from design to operations. This team uses an Image Assessment System (IAS), part of the ground system to characterize and calibrate the on-orbit data.

Geometry of the hemispherical radiometric footprint over plant canopies

NASA Astrophysics Data System (ADS)

Marcolla, B.; Cescatti, A.

2017-11-01

Radiometric measurements of hemispherical surface reflectance and long-wave irradiance are required to quantify the broadband albedo and the outgoing thermal radiation. These observations are typically integrated with eddy covariance measurements of sensible and latent heat fluxes to characterize the surface energy budget. While the aerodynamic footprint has been widely investigated, the geometry of the hemispherical radiometric footprint over plant canopies has been rarely tackled. In the present work, the size and shape of the hemispherical radiometric footprint are formalized for a bare surface and in presence of a vegetation cover. For this purpose, four idealized canopies are analyzed and the dependency of the radiometric footprint on leaf area index and canopy height is explored. Besides, the radiometric footprint is compared with the aerodynamic footprint in conditions of neutral stability. It was observed that almost 100% of the hemispherical radiometric signal originates within a distance of a few radiometer heights, while only about 50-80% of the cumulative aerodynamic signal is generated within a distance of about 20 sensor heights. In order to achieve comparable extensions of the footprint areas, hemispherical radiometric measurements should therefore be taken about 6-15 times higher than turbulent flux ones, depending on the vegetation type. The analysis also highlights that the size of the radiative footprint decreases at increasing leaf area index, whereas the aerodynamic footprint shows an opposite behavior. For the abovementioned reasons, this work may support the interpretation of energy flux measurements and the optimal design of eddy covariance stations located in heterogeneous sites.

Application of radiometric surface temperature for surface energy balance estimation: John Monteith's contributions

USDA-ARS?s Scientific Manuscript database

Over 25 years ago, Huband and Monteith paper’s investigating the radiative surface temperature and the surface energy balance of a wheat canopy, highlighted the key issues in computing fluxes with radiometric surface temperature. These included the relationship between radiometric and aerodynamic s...

Relative radiometric calibration of LANDSAT TM reflective bands

NASA Technical Reports Server (NTRS)

Barker, J. L.

1984-01-01

A common scientific methodology and terminology is outlined for characterizing the radiometry of both TM sensors. The magnitude of the most significant sources of radiometric variability are discussed and methods are recommended for achieving the exceptional potential inherent in the radiometric precision and accuracy of the TM sensors.

Radiometric Characterization of the IKONOS, QuickBird, and OrbView-3 Sensors

NASA Technical Reports Server (NTRS)

Holekamp, Kara

2006-01-01

Radiometric calibration of commercial imaging satellite products is required to ensure that science and application communities can better understand their properties. Inaccurate radiometric calibrations can lead to erroneous decisions and invalid conclusions and can limit intercomparisons with other systems. To address this calibration need, satellite at-sensor radiance values were compared to those estimated by each independent team member to determine the sensor's radiometric accuracy. The combined results of this evaluation provide the user community with an independent assessment of these commercially available high spatial resolution sensors' absolute calibration values.

Radiometric Calibration Assessment of Commercial High Spatial Resolution Multispectral Image Products

NASA Technical Reports Server (NTRS)

Holekamp, Kara; Aaron, David; Thome, Kurtis

2006-01-01

Radiometric calibration of commercial imaging satellite products is required to ensure that science and application communities can better understand their properties. Inaccurate radiometric calibrations can lead to erroneous decisions and invalid conclusions and can limit intercomparisons with other systems. To address this calibration need, satellite at-sensor radiance values were compared to those estimated by each independent team member to determine the sensor's radiometric accuracy. The combined results of this evaluation provide the user community with an independent assessment of these commercially available high spatial resolution sensors' absolute calibration values.

Lower Jurassic Navaho-Aztec-Equivalent Sandstones in southern Arizona and their paleogeographic significance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bilodeau, W.L.; Keith, S.B.

1986-06-01

Thick sequences of Lower Jurassic rhyolitic and andesitic volcanic rocks in several mountain ranges of southern Arizona contain interbedded quartzarenites. Locally up to 250 m thick, these sandstone lenses, composed of well-sorted and well-rounded quartz grains, commonly contain large-scale cross-stratification and are considered to be eolian sand deposits. The eolian sands were blown up against the continental side of the Early Jurassic volcanic arc that trended northwest-southeast across the southwestern margin of the North American continent and/or plate at that time. Paleocurrent data suggest southerly eolian transport of the sands from the Colorado Plateau area. Correlation of these sandstones withmore » the Lower Jurassic Navaho and Aztec Sandstones is indicated by the paleocurrent data as well as radiometric dating of the interbedded volcanics. Eolian sand transport southward across central Arizona in the Early Jurassic indicates that the Mogollon highlands either did not then exist, or were merely low, discontinuous inselbergs on a broad back-arc ramp, more appropriately called the Mogollon slope.« less

Galileo SSI/Ida Radiometrically Calibrated Images V1.0

NASA Astrophysics Data System (ADS)

Domingue, D. L.

2016-05-01

This data set includes Galileo Orbiter SSI radiometrically calibrated images of the asteroid 243 Ida, created using ISIS software and assuming nadir pointing. This is an original delivery of radiometrically calibrated files, not an update to existing files. All images archived include the asteroid within the image frame. Calibration was performed in 2013-2014.

Improved Thermal-Vacuum Compatible Flat Plate Radiometric Source For System-Level Testing Of Optical Sensors

NASA Technical Reports Server (NTRS)

Schwarz, Mark A.; Kent, Craig J.; Bousquet, Robert; Brown, Steven W.

2016-01-01

In this work, we describe an improved thermal-vacuum compatible flat plate radiometric source which has been developed and utilized for the characterization and calibration of remote optical sensors. This source is unique in that it can be used in situ, in both ambient and thermal-vacuum environments, allowing it to follow the sensor throughout its testing cycle. The performance of the original flat plate radiometric source was presented at the 2009 SPIE1. Following the original efforts, design upgrades were incorporated into the source to improve both radiometric throughput and uniformity. The pre-thermal-vacuum (pre-TVAC) testing results of a spacecraft-level optical sensor with the improved flat plate illumination source, both in ambient and vacuum environments, are presented. We also briefly discuss potential FPI configuration changes in order to improve its radiometric performance.

Radiometric age file for Alaska: A section in The United States Geological Survey in Alaska: Accomplishments during 1980

USGS Publications Warehouse

Shew, Nora B.; Wilson, Frederic H.

1982-01-01

The Alaska radiometric age file of the Branch of Alaskan Geology is a computer-based compilation of radiometric dates from the state of Alaska and the western parts of the Yukon Territory and British Columbia. More than 1800 age determinations from over 250 references have been entered in the file. References date back to 1958 and include both published and unpublished sources. The file is the outgrowth of an original radiometric age file compiled by Don Grybeck and students at the University of Alaska-Fairbanks (Turner and others, 1975).

Radiometric calibration updates to the Landsat collection

USGS Publications Warehouse

Micijevic, Esad; Haque, Md. Obaidul; Mishra, Nischal

2016-01-01

The Landsat Project is planning to implement a new collection management strategy for Landsat products generated at the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center. The goal of the initiative is to identify a collection of consistently geolocated and radiometrically calibrated images across the entire Landsat archive that is readily suitable for time-series analyses. In order to perform an accurate land change analysis, the data from all Landsat sensors must be on the same radiometric scale. Landsat 7 Enhanced Thematic Mapper Plus (ETM+) is calibrated to a radiance standard and all previous sensors are cross-calibrated to its radiometric scale. Landsat 8 Operational Land Imager (OLI) is calibrated to both radiance and reflectance standards independently. The Landsat 8 OLI reflectance calibration is considered to be most accurate. To improve radiometric calibration accuracy of historical data, Landsat 1-7 sensors also need to be cross-calibrated to the OLI reflectance scale. Results of that effort, as well as other calibration updates including the absolute and relative radiometric calibration and saturated pixel replacement for Landsat 8 OLI and absolute calibration for Landsat 4 and 5 Thematic Mappers (TM), will be implemented into Landsat products during the archive reprocessing campaign planned within the new collection management strategy. This paper reports on the planned radiometric calibration updates to the solar reflective bands of the new Landsat collection.

Comparison of diverse methods for the correction of atmospheric effects on LANDSAT and SKYLAB images. [radiometric correction in Brazil

NASA Technical Reports Server (NTRS)

Parada, N. D. J. (Principal Investigator); Camara, G.; Dias, L. A. V.; Mascarenhas, N. D. D.; Desouza, R. C. M.; Pereira, A. E. C.

1982-01-01

Earth's atmosphere reduces a sensors ability in currently discriminating targets. Using radiometric correction to reduce the atmospheric effects may improve considerably the performance of an automatic image interpreter. Several methods for radiometric correction from the open literature are compared leading to the development of an atmospheric correction system.

NASA IKONOS Radiometric Characterization

NASA Technical Reports Server (NTRS)

Pagnutti, Mary; Frisbee, Troy; Zanoni, Vicki; Blonski, Slawek; Daehler, Erik; Grant, Brennan; Holekamp, Kara; Ryan, Robert; Sellers, Richard; Smith, Charles

2002-01-01

The objective of this program: Perform radiometric vicarious calibrations of IKQNOS imagery and compare with Space Imaging calibration coefficients The approach taken: utilize multiple well-characterized sites which are widely used by the NASA science community for radiometric characterization of airborne and spaceborne sensors; and to Perform independent characterizations with independent teams. Each team has slightly different measurement techniques and data processing methods.

Experimental methods of indoor millimeter-wave radiometric imaging for personnel concealed contraband detection

NASA Astrophysics Data System (ADS)

Hu, Taiyang; Xiao, Zelong; Li, Hao; Lv, Rongchuan; Lu, Xuan

2014-11-01

The increasingly emerging terrorism attacks and violence crimes around the world have posed severe threats to public security, so carrying out relevant research on advanced experimental methods of personnel concealed contraband detection is crucial and meaningful. All of the advantages of imaging covertly, avoidance of interference with other systems, intrinsic property of being safe to persons under screening , and the superior ability of imaging through natural or manmade obscurants, have significantly combined to enable millimeter-wave (MMW) radiometric imaging to offer great potential in personnel concealed contraband detection. Based upon the current research status of MMW radiometric imaging and urgent demands of personnel security screening, this paper mainly focuses on the experimental methods of indoor MMW radiometric imaging. The reverse radiation noise resulting from super-heterodyne receivers seriously affects the image experiments carried out at short range, so both the generation mechanism and reducing methods of this noise are investigated. Then, the benefit of sky illumination no longer exists for the indoor radiometric imaging, and this leads to the decrease in radiometric temperature contrast between target and background. In order to enhance the radiometric temperature contrast for improving indoor imaging performance, the noise illumination technique is adopted in the indoor imaging scenario. In addition, the speed and accuracy of concealed contraband detection from acquired MMW radiometric images are usually restricted to the deficiencies in traditional artificial interpretation by security inspectors, thus an automatic recognition and location algorithm by integrating improved Fuzzy C-means clustering with moment invariants is put forward. A series of original results are also presented to demonstrate the significance and validity of these methods.

English/Russian terminology on radiometric calibration of space-borne optoelectronic sensors

NASA Astrophysics Data System (ADS)

Privalsky, V.; Zakharenkov, V.; Humpherys, T.; Sapritsky, V.; Datla, R.

The efficient use of data acquired through exo-atmospheric observations of the Earth within the framework of existing and newly planned programs requires a unique understanding of respective terms and definitions. Yet, the last large-scale document on the subject - The International Electrotechnical Vocabulary - had been published 18 years ago. This lack of a proper document, which would reflect the changes that had occurred in the area since that time, is especially detrimental to the developing international efforts aimed at global observations of the Earth from space such as the Global Earth Observations Program proposed by the U.S.A. at the 2003 WMO Congress. To cover this gap at least partially, a bi-lingual explanatory dictionary of terms and definitions in the area of radiometric calibration of space-borne IR sensors is developed. The objectives are to produce a uniform terminology for the global space-borne observations of the Earth, establish a unique understanding of terms and definitions by the radiometric communities, including a correspondence between the Russian and American terms and definitions, and to develop a formal English/Russian reference dictionary for use by scientists and engineers involved in radiometric observations of the Earth from space. The dictionary includes close to 400 items covering basic concepts of geometric, wave and corpuscular optics, remote sensing technologies, and ground-based calibration as well as more detailed treatment of terms and definitions in the areas of radiometric quantities, symbols and units, optical phenomena and optical properties of objects and media, and radiometric systems and their properties. The dictionary contains six chapters: Basic Concepts, Quantities, Symbols, and Units, Optical phenomena, Optical characteristics of surfaces and media, Components of Radiometric Systems, Characteristics of radiometric system components, plus English/Russian and Russian/Inglish indices.

Intra-annual NDVI validation of the Landsat 5 TM radiometric calibration

USGS Publications Warehouse

Chander, G.; Groeneveld, D.P.

2009-01-01

Multispectral data from the Landsat 5 (L5) Thematic Mapper (TM) sensor provide the backbone of the extensive archive of moderate‐resolution Earth imagery. Even after more than 24 years of service, the L5 TM is still operational. Given the longevity of the satellite, the detectors have aged and the sensor's radiometric characteristics have changed since launch. The calibration procedures and parameters in the National Land Archive Production System (NLAPS) have also changed with time. Revised radiometric calibrations in 2003 and 2007 have improved the radiometric accuracy of recently processed data. This letter uses the Normalized Difference Vegetation Index (NDVI) as a metric to evaluate the radiometric calibration. The calibration change has improved absolute calibration accuracy, consistency over time, and consistency with Landsat 7 (L7) Enhanced Thematic radiometry and will provide the basis for continued long‐term studies of the Earth's land surfaces.

Laboratory Measurement of Bidirectional Reflectance of Radiometric Tarps

NASA Technical Reports Server (NTRS)

Knowlton, Kelly

2006-01-01

Objectives: a) To determine the magnitude of radiometric tarp BRDF; b) To determine whether an ASD FieldSpec Pro spectroradiometer can be used to perform the experiment. Radiometric tarps with nominal reflectance values of 52%, 35%, and 3.5%, deployed for IKONOS. QuickBird, and OrbView-3 overpasses Ground-based spectroradiometric measurements of tarp and Spectralon@ panel taken during overpass using ASD FieldSpec Pro spectroradiometer, and tarp reflectance calculated. Reflectance data used in atmospheric radiative transfer model (MODTRAN) to predict satellite at-sensor radiance for radiometric calibration. Reflectance data also used to validate atmospheric correction of high-spatial-resolution multispectral image products

Reflectance characteristics of the Viking lander camera reference test charts

NASA Technical Reports Server (NTRS)

Wall, S. D.; Burcher, E. E.; Jabson, D. J.

1975-01-01

Reference test charts provide radiometric, colorimetric, and spatial resolution references for the Viking lander cameras on Mars. Reflectance measurements of these references are described, including the absolute bidirectional reflectance of the radiometric references and the relative spectral reflectance of both radiometric and colorimetric references. Results show that the bidirection reflectance of the radiometric references is Lambertian to within + or - 7% for incidence angles between 20 deg and 60 deg, and that their spectral reflectance is constant with wavelength to within + or - 5% over the spectral range of the cameras. Estimated accuracy of the measurements is + or - 0.05 in relative spectral reflectance.

Improved Absolute Radiometric Calibration of a UHF Airborne Radar

NASA Technical Reports Server (NTRS)

Chapin, Elaine; Hawkins, Brian P.; Harcke, Leif; Hensley, Scott; Lou, Yunling; Michel, Thierry R.; Moreira, Laila; Muellerschoen, Ronald J.; Shimada, Joanne G.; Tham, Kean W.;

Novel dental dynamic depth profilometric imaging using simultaneous frequency-domain infrared photothermal radiometry and laser luminescence

NASA Astrophysics Data System (ADS)

Nicolaides, Lena; Mandelis, Andreas

2000-01-01

A high-spatial-resolution dynamic experimental imaging setup, which can provide simultaneous measurements of laser- induced frequency-domain infrared photothermal radiometric and luminescence signals from defects in teeth, has been developed for the first time. The major findings of this work are: (1) radiometric images are complementary to (anticorrelated with) luminescence images, as a result of the nature of the two physical signal generation processes; (2) the radiometric amplitude exhibits much superior dynamic (signal resolution) range to luminescence in distinguishing between intact and cracked sub-surface structures in the enamel; (3) the radiometric signal (amplitude and phase) produces dental images with much better defect localization, delineation, and resolution; (4) radiometric images (amplitude and phase) at a fixed modulation frequency are depth profilometric, whereas luminescence images are not; and (5) luminescence frequency responses from enamel and hydroxyapatite exhibit two relaxation lifetimes, the longer of which (approximately ms) is common to all and is not sensitive to the defect state and overall quality of the enamel. Simultaneous radiometric and luminescence frequency scans for the purpose of depth profiling were performed and a quantitative theoretical two-lifetime rate model of dental luminescence was advanced.

New Laboratory Technique to Determine Thermal Conductivity of Complex Regolith Simulants Under High Vacuum

NASA Astrophysics Data System (ADS)

Ryan, A. J.; Christensen, P. R.

2016-12-01

Laboratory measurements have been necessary to interpret thermal data of planetary surfaces for decades. We present a novel radiometric laboratory method to determine temperature-dependent thermal conductivity of complex regolith simulants under high vacuum and across a wide range of temperatures. Here, we present our laboratory method, strategy, and initial results. This method relies on radiometric temperature measurements instead of contact measurements, eliminating the need to disturb the sample with thermal probes. We intend to determine the conductivity of grains that are up to 2 cm in diameter and to parameterize the effects of angularity, sorting, layering, composition, and cementation. These results will support the efforts of the OSIRIS-REx team in selecting a site on asteroid Bennu that is safe and meets grain size requirements for sampling. Our system consists of a cryostat vacuum chamber with an internal liquid nitrogen dewar. A granular sample is contained in a cylindrical cup that is 4 cm in diameter and 1 to 6 cm deep. The surface of the sample is exposed to vacuum and is surrounded by a black liquid nitrogen cold shroud. Once the system has equilibrated at 80 K, the base of the sample cup is rapidly heated to 450 K. An infrared camera observes the sample from above to monitor its temperature change over time. We have built a time-dependent finite element model of the experiment in COMSOL Multiphysics. Boundary temperature conditions and all known material properties (including surface emissivities) are included to replicate the experiment as closely as possible. The Optimization module in COMSOL is specifically designed for parameter estimation. Sample thermal conductivity is assumed to be a quadratic or cubic polynomial function of temperature. We thus use gradient-based optimization methods in COMSOL to vary the polynomial coefficients in an effort to reduce the least squares error between the measured and modeled sample surface temperature.

Mapping surface soil moisture with L-band radiometric measurements

NASA Technical Reports Server (NTRS)

Wang, James R.; Shiue, James C.; Schmugge, Thomas J.; Engman, Edwin T.

1989-01-01

A NASA C-130 airborne remote sensing aircraft was used to obtain four-beam pushbroom microwave radiometric measurements over two small Kansas tall-grass prairie region watersheds, during a dry-down period after heavy rainfall in May and June, 1987. While one of the watersheds had been burned 2 months before these measurements, the other had not been burned for over a year. Surface soil-moisture data were collected at the time of the aircraft measurements and correlated with the corresponding radiometric measurements, establishing a relationship for surface soil-moisture mapping. Radiometric sensitivity to soil moisture variation is higher in the burned than in the unburned watershed; surface soil moisture loss is also faster in the burned watershed.

The radiometric characteristics of KOMPSAT-3A by using reference radiometric tarps and ground measurement

NASA Astrophysics Data System (ADS)

Yeom, Jong-Min

2016-09-01

In this study, we performed the vicarious radiometric calibration of KOMPSAT-3A multispectral bands by using 6S radiative transfer model, radiometric tarps, MFRSR measurements. Furthermore, to prepare the accurate input parameter, we also did experiment work to measure the BRDF of radiometric tarps based on hyperspectral gonioradiometer to compensate the observation geometry difference between satellite and ASD Fieldspec 3. Also, we measured point spread function (PSF) by using the bright star and corrected multispectral bands based on the Wiener filter. For accurate atmospheric constituent effects such as aerosol optical depth, column water, and total ozone, we used MFRSR instrument and estimated related optical depth of each gases. Based on input parameters for 6S radiative transfer model, we simulated top of atmosphere (TOA) radiance by observed by KOMPSAT-3A and matched-up the digital number. Consequently, DN to radiance coefficients was determined based on aforementioned methods and showed reasonable statistics results.

Landsat-8 Operational Land Imager (OLI) radiometric performance on-orbit

USGS Publications Warehouse

Morfitt, Ron; Barsi, Julia A.; Levy, Raviv; Markham, Brian L.; Micijevic, Esad; Ong, Lawrence; Scaramuzza, Pat; Vanderwerff, Kelly

2015-01-01

Expectations of the Operational Land Imager (OLI) radiometric performance onboard Landsat-8 have been met or exceeded. The calibration activities that occurred prior to launch provided calibration parameters that enabled ground processing to produce imagery that met most requirements when data were transmitted to the ground. Since launch, calibration updates have improved the image quality even more, so that all requirements are met. These updates range from detector gain coefficients to reduce striping and banding to alignment parameters to improve the geometric accuracy. This paper concentrates on the on-orbit radiometric performance of the OLI, excepting the radiometric calibration performance. Topics discussed in this paper include: signal-to-noise ratios that are an order of magnitude higher than previous Landsat missions; radiometric uniformity that shows little residual banding and striping, and continues to improve; a dynamic range that limits saturation to extremely high radiance levels; extremely stable detectors; slight nonlinearity that is corrected in ground processing; detectors that are stable and 100% operable; and few image artifacts.

Numerical study of radiometric forces via the direct solution of the Boltzmann kinetic equation

NASA Astrophysics Data System (ADS)

Anikin, Yu. A.

2011-07-01

The two-dimensional rarefied gas motion in a Crookes radiometer and the resulting radiometric forces are studied by numerically solving the Boltzmann kinetic equation. The collision integral is directly evaluated using a projection method, and second-order accurate TVD schemes are used to solve the advection equation. The radiometric forces are found as functions of the Knudsen number and the temperatures, and their spatial distribution is analyzed.

Artifact correction and absolute radiometric calibration techniques employed in the Landsat 7 image assessment system

USGS Publications Warehouse

Boncyk, Wayne C.; Markham, Brian L.; Barker, John L.; Helder, Dennis

1996-01-01

The Landsat-7 Image Assessment System (IAS), part of the Landsat-7 Ground System, will calibrate and evaluate the radiometric and geometric performance of the Enhanced Thematic Mapper Plus (ETM +) instrument. The IAS incorporates new instrument radiometric artifact correction and absolute radiometric calibration techniques which overcome some limitations to calibration accuracy inherent in historical calibration methods. Knowledge of ETM + instrument characteristics gleaned from analysis of archival Thematic Mapper in-flight data and from ETM + prelaunch tests allow the determination and quantification of the sources of instrument artifacts. This a priori knowledge will be utilized in IAS algorithms designed to minimize the effects of the noise sources before calibration, in both ETM + image and calibration data.

Radiometric Characterization Results for the IKONOS, Quickbird, and OrbView-3 Sensor

NASA Technical Reports Server (NTRS)

Holekamp, Kara; Aaron, David; Thome, Kurtis

2006-01-01

Radiometric calibration of commercial imaging satellite products is required to ensure that science and application communities better understand commercial imaging satellite properties. Inaccurate radiometric calibrations can lead to erroneous decisions and invalid conclusions and can limit intercomparisons with other systems. To address this calibration need, the NASA Applied Sciences Directorate (ASD) at Stennis Space Center established a commercial satellite imaging radiometric calibration team consisting of three independent groups: NASA ASD, the University of Arizona Remote Sensing Group, and South Dakota State University. Each group independently determined the absolute radiometric calibration coefficients of available high-spatial-resolution commercial 4-band multispectral products, in the visible though near-infrared spectrum, from GeoEye(tradeMark) (formerly SpaceImaging(Registered TradeMark)) IKONOS, DigitalGlobe(Regitered TradeMark) QuickBird, and GeoEye (formerly ORBIMAGE(Registered TradeMark) OrbView. Each team member employed some variant of reflectance-based vicarious calibration approach, requiring ground-based measurements coincident with image acquisitions and radiative transfer calculations. Several study sites throughout the United States that covered a significant portion of the sensor's dynamic range were employed. Satellite at-sensor radiance values were compared to those estimated by each independent team member to evaluate the sensor's radiometric accuracy. The combined results of this evaluation provide the user community with an independent assessment of these sensors' absolute calibration values.

PHASS99: A software program for retrieving and decoding the radiometric ages of igneous rocks from the international database IGBADAT

NASA Astrophysics Data System (ADS)

Al-Mishwat, Ali T.

2016-05-01

PHASS99 is a FORTRAN program designed to retrieve and decode radiometric and other physical age information of igneous rocks contained in the international database IGBADAT (Igneous Base Data File). In the database, ages are stored in a proprietary format using mnemonic representations. The program can handle up to 99 ages in an igneous rock specimen and caters to forty radiometric age systems. The radiometric age alphanumeric strings assigned to each specimen description in the database consist of four components: the numeric age and its exponential modifier, a four-character mnemonic method identification, a two-character mnemonic name of analysed material, and the reference number in the rock group bibliography vector. For each specimen, the program searches for radiometric age strings, extracts them, parses them, decodes the different age components, and converts them to high-level English equivalents. IGBADAT and similarly-structured files are used for input. The output includes three files: a flat raw ASCII text file containing retrieved radiometric age information, a generic spreadsheet-compatible file for data import to spreadsheets, and an error file. PHASS99 builds on the old program TSTPHA (Test Physical Age) decoder program and expands greatly its capabilities. PHASS99 is simple, user friendly, fast, efficient, and does not require users to have knowledge of programing.

Vicarious absolute radiometric calibration of GF-2 PMS2 sensor using permanent artificial targets in China

NASA Astrophysics Data System (ADS)

Liu, Yaokai; Li, Chuanrong; Ma, Lingling; Wang, Ning; Qian, Yonggang; Tang, Lingli

2016-10-01

GF-2, launched on August 19 2014, is one of the high-resolution land resource observing satellite of the China GF series satellites plan. The radiometric performance evaluation of the onboard optical pan and multispectral (PMS2) sensor of GF-2 satellite is very important for the further application of the data. And, the vicarious absolute radiometric calibration approach is one of the most useful way to monitor the radiometric performance of the onboard optical sensors. In this study, the traditional reflectance-based method is used to vicarious radiometrically calibrate the onboard PMS2 sensor of GF-2 satellite using three black, gray and white reflected permanent artificial targets located in the AOE Baotou site in China. Vicarious field calibration campaign were carried out in the AOE-Baotou calibration site on 22 April 2016. And, the absolute radiometric calibration coefficients were determined with in situ measured atmospheric parameters and surface reflectance of the permanent artificial calibration targets. The predicted TOA radiance of a selected desert area with our determined calibrated coefficients were compared with the official distributed calibration coefficients. Comparison results show a good consistent and the mean relative difference of the multispectral channels is less than 5%. Uncertainty analysis was also carried out and a total uncertainty with 3.87% is determined of the TOA radiance.

Determination of the microbolometric FPA's responsivity with imaging system's radiometric considerations

NASA Astrophysics Data System (ADS)

Gogler, Slawomir; Bieszczad, Grzegorz; Krupinski, Michal

2013-10-01

Thermal imagers and used therein infrared array sensors are subject to calibration procedure and evaluation of their voltage sensitivity on incident radiation during manufacturing process. The calibration procedure is especially important in so-called radiometric cameras, where accurate radiometric quantities, given in physical units, are of concern. Even though non-radiometric cameras are not expected to stand up to such elevated standards, it is still important, that the image faithfully represents temperature variations across the scene. Detectors used in thermal camera are illuminated by infrared radiation transmitted through an infrared transmitting optical system. Often an optical system, when exposed to uniform Lambertian source forms a non-uniform irradiation distribution in its image plane. In order to be able to carry out an accurate non-uniformity correction it is essential to correctly predict irradiation distribution from a uniform source. In the article a non-uniformity correction method has been presented, that takes into account optical system's radiometry. Predictions of the irradiation distribution have been confronted with measured irradiance values. Presented radiometric model allows fast and accurate non-uniformity correction to be carried out.

Adjustments to the MODIS Terra Radiometric Calibration and Polarization Sensitivity in the 2010 Reprocessing

NASA Technical Reports Server (NTRS)

Meister, Gerhard; Franz, Bryan A.

2011-01-01

The Moderate-Resolution Imaging Spectroradiometer (MODIS) on NASA s Earth Observing System (EOS) satellite Terra provides global coverage of top-of-atmosphere (TOA) radiances that have been successfully used for terrestrial and atmospheric research. The MODIS Terra ocean color products, however, have been compromised by an inadequate radiometric calibration at the short wavelengths. The Ocean Biology Processing Group (OBPG) at NASA has derived radiometric corrections using ocean color products from the SeaWiFS sensor as truth fields. In the R2010.0 reprocessing, these corrections have been applied to the whole mission life span of 10 years. This paper presents the corrections to the radiometric gains and to the instrument polarization sensitivity, demonstrates the improvement to the Terra ocean color products, and discusses issues that need further investigation. Although the global averages of MODIS Terra ocean color products are now in excellent agreement with those of SeaWiFS and MODIS Aqua, and image quality has been significantly improved, the large corrections applied to the radiometric calibration and polarization sensitivity require additional caution when using the data.

Feasibility Study of Radiometry for Airborne Detection of Aviation Hazards

NASA Technical Reports Server (NTRS)

Gimmestad, Gary G.; Papanicolopoulos, Chris D.; Richards, Mark A.; Sherman, Donald L.; West, Leanne L.; Johnson, James W. (Technical Monitor)

2001-01-01

Radiometric sensors for aviation hazards have the potential for widespread and inexpensive deployment on aircraft. This report contains discussions of three aviation hazards - icing, turbulence, and volcanic ash - as well as candidate radiometric detection techniques for each hazard. Dual-polarization microwave radiometry is the only viable radiometric technique for detection of icing conditions, but more research will be required to assess its usefulness to the aviation community. Passive infrared techniques are being developed for detection of turbulence and volcanic ash by researchers in this country and also in Australia. Further investigation of the infrared airborne radiometric hazard detection approaches will also be required in order to develop reliable detection/discrimination techniques. This report includes a description of a commercial hyperspectral imager for investigating the infrared detection techniques for turbulence and volcanic ash.

HiRadProp: High-Frequency Modeling and Prediction of Tropospheric Radiopropagation Parameters from Ground-Based-Multi-Channel Radiometric Measurements between Ka and W Band

DTIC Science & Technology

2016-05-11

new physically -based prediction models for all-weather path attenuation estimation at Ka, V and W band from multi- channel microwave radiometric data...of new physically -based prediction models for all-weather path attenuation estimation at Ka, V and W band from multi- channel microwave radiometric...the medium behavior at these frequency bands from both a physical and a statistical point of view (e.g., [5]-[7]). However, these campaigns are

Economic Outlook for Radiometric Selection of Ores; POSSIBILITES OUVERTES EN MATIERE ECONOMIQUE PAR SELECTION RADIOMETRIQUE DES MINERAIS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Formery, P.; Ziegler, V.

1959-10-31

The radiometric grading of uranium ores is analyzed. The cut-off is defined, and its parameters are derived. Cut-off above ground and underground are statistically interpreted. An evaluation is made of the combined effects of both kinds of cut-off made in succession. The corrections to be made to the radiometric apparatus used are determined. Application of the theory of cutoff to the evaluation of reserves is discussed. (J.S.R.)

Study of Spectral/Radiometric Characteristics of the Thematic Mapper for Land Use Applications

NASA Technical Reports Server (NTRS)

Malila, W. A. (Principal Investigator); Metzler, M. D. (Principal Investigator)

1985-01-01

An investigation conducted in support of the LANDSAT 4/5 Image Data Quality Analysis (LIDQA) Program is discussed. Results of engineering analyses of radiometric, spatial, spectral, and geometric properties of the Thematic Mapper systems are summarized; major emphasis is placed on the radiometric analysis. Details of the analyses are presented in appendices, which contain three of the eight technical papers produced during this investigation; these three, together, describe the major activities and results of the investigation.

Teaching the Mathematics of Radioactive Dating.

ERIC Educational Resources Information Center

Shea, James H.

2001-01-01

Describes a method used to teach the concept of radiometric dating using mathematical equations. Explores the lack of information in textbooks on how to solve radiometric dating problems using mathematical concepts. (SAH)

Advanced Land Imager Assessment System

NASA Technical Reports Server (NTRS)

Chander, Gyanesh; Choate, Mike; Christopherson, Jon; Hollaren, Doug; Morfitt, Ron; Nelson, Jim; Nelson, Shar; Storey, James; Helder, Dennis; Ruggles, Tim;

Broadband radiometric LED measurements

NASA Astrophysics Data System (ADS)

Eppeldauer, G. P.; Cooksey, C. C.; Yoon, H. W.; Hanssen, L. M.; Podobedov, V. B.; Vest, R. E.; Arp, U.; Miller, C. C.

2016-09-01

At present, broadband radiometric LED measurements with uniform and low-uncertainty results are not available. Currently, either complicated and expensive spectral radiometric measurements or broadband photometric LED measurements are used. The broadband photometric measurements are based on the CIE standardized V(λ) function, which cannot be used in the UV range and leads to large errors when blue or red LEDs are measured in its wings, where the realization is always poor. Reference irradiance meters with spectrally constant response and high-intensity LED irradiance sources were developed here to implement the previously suggested broadband radiometric LED measurement procedure [1, 2]. Using a detector with spectrally constant response, the broadband radiometric quantities of any LEDs or LED groups can be simply measured with low uncertainty without using any source standard. The spectral flatness of filtered-Si detectors and low-noise pyroelectric radiometers are compared. Examples are given for integrated irradiance measurement of UV and blue LED sources using the here introduced reference (standard) pyroelectric irradiance meters. For validation, the broadband measured integrated irradiance of several LED-365 sources were compared with the spectrally determined integrated irradiance derived from an FEL spectral irradiance lamp-standard. Integrated responsivity transfer from the reference irradiance meter to transfer standard and field UV irradiance meters is discussed.

Design and analysis of radiometric instruments using high-level numerical models and genetic algorithms

NASA Astrophysics Data System (ADS)

Sorensen, Ira Joseph

A primary objective of the effort reported here is to develop a radiometric instrument modeling environment to provide complete end-to-end numerical models of radiometric instruments, integrating the optical, electro-thermal, and electronic systems. The modeling environment consists of a Monte Carlo ray-trace (MCRT) model of the optical system coupled to a transient, three-dimensional finite-difference electrothermal model of the detector assembly with an analytic model of the signal-conditioning circuitry. The environment provides a complete simulation of the dynamic optical and electrothermal behavior of the instrument. The modeling environment is used to create an end-to-end model of the CERES scanning radiometer, and its performance is compared to the performance of an operational CERES total channel as a benchmark. A further objective of this effort is to formulate an efficient design environment for radiometric instruments. To this end, the modeling environment is then combined with evolutionary search algorithms known as genetic algorithms (GA's) to develop a methodology for optimal instrument design using high-level radiometric instrument models. GA's are applied to the design of the optical system and detector system separately and to both as an aggregate function with positive results.

Laboratory-Based Bidirectional Reflectance Distribution Functions of Radiometric Tarps

NASA Technical Reports Server (NTRS)

Georgiev, Georgi T.; Butler, James J.

2008-01-01

Laboratory-based bidirectional reflectance distribution functions of radiometric tarp samples used in the vicarious calibration of Earth remote sensing satellite instruments are presented in this paper. The results illustrate the BRDF dependence on the orientation of the tarps weft and warp threads. The study was performed using the GSFC scatterometer at incident zenith angles of 0 deg, 10 deg, and 30 deg; scatter zenith angles from 0 deg. to 60 deg.; and scatter azimuth angles of 0 deg., 45 deg., 90 deg., 135 deg. and 180 deg. The wavelengths were 485nm, 550nm, 633nm and 800nm. The tarp's weft and warp dependence on BRDF is well defined at all measurement geometries and wavelengths. The BRDF difference can be as high as 8% at 0o incident angle and 12% at 30 deg. incident angle. The fitted BRDF data shows a very small discrepancy from the measured ones. New data on the forward and backscatter properties of radiometric tarps are reported. The backward scatter is well pronounced for the white samples. The black sample has well pronounced forward scatter. The provided BRDF characterization of radiometric tarps is an excellent reference for anyone interested in using tarps for radiometric calibrations. The results are NIST traceable.

LANDSAT-D data format control book. Volume 6: (Products)

NASA Technical Reports Server (NTRS)

Kabat, F.

1981-01-01

Four basic product types are generated from the raw thematic mapper (TM) and multispectral scanner (MSS) payload data by the NASA GSFC LANDSAT 4 data management system: (1) unprocessed data (raw sensor data); (2) partially processed data, which consists of radiometrically corrected sensor data with geometric correction information appended; (3) fully processed data, which consists of radiometrically and geometrically corrected sensor data; and (4) inventory data which consists of summary information about product types 2 and 3. High density digital recorder formatting and the radiometric correction process are described. Geometric correction information is included.

SNPP VIIRS RSB Earth View Reflectance Uncertainty

NASA Technical Reports Server (NTRS)

Lei, Ning; Twedt, Kevin; McIntire, Jeff; Xiong, Xiaoxiong

2017-01-01

The Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi National Polar-orbiting Partnership (SNPP) satellite uses its 14 reflective solar bands to passively collect solar radiant energy reflected off the Earth. The Level 1 product is the geolocated and radiometrically calibrated top-of- the-atmosphere solar reflectance. The absolute radiometric uncertainty associated with this product includes contributions from the noise associated with measured detector digital counts and the radiometric calibration bias. Here, we provide a detailed algorithm for calculating the estimated standard deviation of the retrieved top-of-the-atmosphere spectral solar radiation reflectance.

Numerical study of the radiometric phenomenon exhibited by a rotating Crookes radiometer

NASA Astrophysics Data System (ADS)

Anikin, Yu. A.

2011-11-01

The two-dimensional rarefied gas flow around a rotating Crookes radiometer and the arising radiometric forces are studied by numerically solving the Boltzmann kinetic equation. The computations are performed in a noninertial frame of reference rotating together with the radiometer. The collision integral is directly evaluated using a projection method, while second- and third-order accurate TVD schemes are used to solve the advection equation and the equation for inertia-induced transport in the velocity space, respectively. The radiometric forces are found as functions of the rotation frequency.

An Empirical Approach to Ocean Color Data: Reducing Bias and the Need for Post-Launch Radiometric Re-Calibration

NASA Technical Reports Server (NTRS)

Gregg, Watson W.; Casey, Nancy W.; O'Reilly, John E.; Esaias, Wayne E.

2009-01-01

A new empirical approach is developed for ocean color remote sensing. Called the Empirical Satellite Radiance-In situ Data (ESRID) algorithm, the approach uses relationships between satellite water-leaving radiances and in situ data after full processing, i.e., at Level-3, to improve estimates of surface variables while relaxing requirements on post-launch radiometric re-calibration. The approach is evaluated using SeaWiFS chlorophyll, which is the longest time series of the most widely used ocean color geophysical product. The results suggest that ESRID 1) drastically reduces the bias of ocean chlorophyll, most impressively in coastal regions, 2) modestly improves the uncertainty, and 3) reduces the sensitivity of global annual median chlorophyll to changes in radiometric re-calibration. Simulated calibration errors of 1% or less produce small changes in global median chlorophyll (less than 2.7%). In contrast, the standard NASA algorithm set is highly sensitive to radiometric calibration: similar 1% calibration errors produce changes in global median chlorophyll up to nearly 25%. We show that 0.1% radiometric calibration error (about 1% in water-leaving radiance) is needed to prevent radiometric calibration errors from changing global annual median chlorophyll more than the maximum interannual variability observed in the SeaWiFS 9-year record (+/- 3%), using the standard method. This is much more stringent than the goal for SeaWiFS of 5% uncertainty for water leaving radiance. The results suggest ocean color programs might consider less emphasis of expensive efforts to improve post-launch radiometric re-calibration in favor of increased efforts to characterize in situ observations of ocean surface geophysical products. Although the results here are focused on chlorophyll, in principle the approach described by ESRID can be applied to any surface variable potentially observable by visible remote sensing.

OrbView-3 Technical Performance Evaluation 2005: Modulation Transfer Function

NASA Technical Reports Server (NTRS)

Cole, Aaron

2007-01-01

The Technical performance evaluation of OrbView-3 using the Modulation Transfer Function (MTF) is presented. The contents include: 1) MTF Results and Methodology; 2) Radiometric Calibration Methodology; and 3) Relative Radiometric Assessment Results

Radiometric Dating Does Work!

ERIC Educational Resources Information Center

Dalrymple, G. Brent

2000-01-01

Discusses the accuracy of dating methods and creationist arguments that radiometric dating does not work. Explains the Manson meteorite impact and the Pierre shale, the ages of meteorites, the K-T tektites, and dating the Mount Vesuvius eruption. (Author/YDS)

Revised Radiometric Calibration Technique for LANDSAT-4 Thematic Mapper Data by the Canada Centre for Remote Sensing

NASA Technical Reports Server (NTRS)

Murphy, J.; Butlin, T.; Duff, P.; Fitzgerald, A.

1984-01-01

A technique for the radiometric correction of LANDSAT-4 Thematic Mapper data was proposed by the Canada Center for Remote Sensing. Subsequent detailed observations of raw image data, raw radiometric calibration data and background measurements extracted from the raw data stream on High Density Tape highlighted major shortcomings in the proposed method which if left uncorrected, can cause severe radiometric striping in the output product. Results are presented which correlate measurements of the DC background with variations in both image data background and calibration samples. The effect on both raw data and on data corrected using the earlier proposed technique is explained, and the correction required for these factors as a function of individual scan line number for each detector is described. It is shown how the revised technique can be incorporated into an operational environment.

Validation of Radiometric Standards for the Laboratory Calibration of Reflected-Solar Earth Observing Satellite Instruments

NASA Technical Reports Server (NTRS)

Butler, James J.; Johnson, B. Carol; Rice, Joseph P.; Brown, Steven W.; Barnes, Robert A.

2007-01-01

Historically, the traceability of the laboratory calibration of Earth-observing satellite instruments to a primary radiometric reference scale (SI units) is the responsibility of each instrument builder. For the NASA Earth Observing System (EOS), a program has been developed using laboratory transfer radiometers, each with its own traceability to the primary radiance scale of a national metrology laboratory, to independently validate the radiances assigned to the laboratory sources of the instrument builders. The EOS Project Science Office also developed a validation program for the measurement of onboard diffuse reflecting plaques, which are also used as radiometric standards for Earth-observing satellite instruments. Summarized results of these validation campaigns, with an emphasis on the current state-of-the-art uncertainties in laboratory radiometric standards, will be presented. Future mission uncertainty requirements, and possible enhancements to the EOS validation program to ensure that those uncertainties can be met, will be presented.

Landsat-5 TM reflective-band absolute radiometric calibration

USGS Publications Warehouse

Chander, G.; Helder, D.L.; Markham, B.L.; Dewald, J.D.; Kaita, E.; Thome, K.J.; Micijevic, E.; Ruggles, T.A.

2004-01-01

The Landsat-5 Thematic Mapper (TM) sensor provides the longest running continuous dataset of moderate spatial resolution remote sensing imagery, dating back to its launch in March 1984. Historically, the radiometric calibration procedure for this imagery used the instrument's response to the Internal Calibrator (IC) on a scene-by-scene basis to determine the gain and offset of each detector. Due to observed degradations in the IC, a new procedure was implemented for U.S.-processed data in May 2003. This new calibration procedure is based on a lifetime radiometric calibration model for the instrument's reflective bands (1-5 and 7) and is derived, in part, from the IC response without the related degradation effects and is tied to the cross calibration with the Landsat-7 Enhanced Thematic Mapper Plus. Reflective-band absolute radiometric accuracy of the instrument tends to be on the order of 7% to 10%, based on a variety of calibration methods.

Analysis of the Radiometric Response of Orange Tree Crown in Hyperspectral Uav Images

NASA Astrophysics Data System (ADS)

Imai, N. N.; Moriya, E. A. S.; Honkavaara, E.; Miyoshi, G. T.; de Moraes, M. V. A.; Tommaselli, A. M. G.; Näsi, R.

2017-10-01

High spatial resolution remote sensing images acquired by drones are highly relevant data source in many applications. However, strong variations of radiometric values are difficult to correct in hyperspectral images. Honkavaara et al. (2013) presented a radiometric block adjustment method in which hyperspectral images taken from remotely piloted aerial systems - RPAS were processed both geometrically and radiometrically to produce a georeferenced mosaic in which the standard Reflectance Factor for the nadir is represented. The plants crowns in permanent cultivation show complex variations since the density of shadows and the irradiance of the surface vary due to the geometry of illumination and the geometry of the arrangement of branches and leaves. An evaluation of the radiometric quality of the mosaic of an orange plantation produced using images captured by a hyperspectral imager based on a tunable Fabry-Pérot interferometer and applying the radiometric block adjustment method, was performed. A high-resolution UAV based hyperspectral survey was carried out in an orange-producing farm located in Santa Cruz do Rio Pardo, state of São Paulo, Brazil. A set of 25 narrow spectral bands with 2.5 cm of GSD images were acquired. Trend analysis was applied to the values of a sample of transects extracted from plants appearing in the mosaic. The results of these trend analysis on the pixels distributed along transects on orange tree crown showed the reflectance factor presented a slightly trend, but the coefficients of the polynomials are very small, so the quality of mosaic is good enough for many applications.

Cross-Calibration between ASTER and MODIS Visible to Near-Infrared Bands for Improvement of ASTER Radiometric Calibration

PubMed Central

Tsuchida, Satoshi; Thome, Kurtis

2017-01-01

Radiometric cross-calibration between the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and the Terra-Moderate Resolution Imaging Spectroradiometer (MODIS) has been partially used to derive the ASTER radiometric calibration coefficient (RCC) curve as a function of date on visible to near-infrared bands. However, cross-calibration is not sufficiently accurate, since the effects of the differences in the sensor’s spectral and spatial responses are not fully mitigated. The present study attempts to evaluate radiometric consistency across two sensors using an improved cross-calibration algorithm to address the spectral and spatial effects and derive cross-calibration-based RCCs, which increases the ASTER calibration accuracy. Overall, radiances measured with ASTER bands 1 and 2 are on averages 3.9% and 3.6% greater than the ones measured on the same scene with their MODIS counterparts and ASTER band 3N (nadir) is 0.6% smaller than its MODIS counterpart in current radiance/reflectance products. The percentage root mean squared errors (%RMSEs) between the radiances of two sensors are 3.7, 4.2, and 2.3 for ASTER band 1, 2, and 3N, respectively, which are slightly greater or smaller than the required ASTER radiometric calibration accuracy (4%). The uncertainty of the cross-calibration is analyzed by elaborating the error budget table to evaluate the International System of Units (SI)-traceability of the results. The use of the derived RCCs will allow further reduction of errors in ASTER radiometric calibration and subsequently improve interoperability across sensors for synergistic applications. PMID:28777329

Radiometric temperature reference

NASA Technical Reports Server (NTRS)

Monford, L. G., Jr.

1969-01-01

Radiometric Temperature Reference uses a thermistor as both a heating and sensing element to maintain its resistance at a preselected level to continuously control the power supplying it. The fixed infrared radiation level must be simple, rugged, and capable of high temperature operation.

Flight Technology Improvement. [spaceborne optical radiometric instruments, attitude control, and electromechanical and power subsystems

NASA Technical Reports Server (NTRS)

1979-01-01

Shortcomings in spaceborne instrumentation technology are analyzed and recommendations are given for corrections and technology development. The technologies discussed are optical radiometric instruments and calibration, attitude control and determination, and electromechanical and power subsystems.

Broadband Radiometric LED Measurements

PubMed Central

Eppeldauer, G. P.; Cooksey, C. C.; Yoon, H. W.; Hanssen, L. M.; Podobedov, V. B.; Vest, R. E.; Arp, U.; Miller, C. C.

2017-01-01

At present, broadband radiometric measurements of LEDs with uniform and low-uncertainty results are not available. Currently, either complicated and expensive spectral radiometric measurements or broadband photometric LED measurements are used. The broadband photometric measurements are based on the CIE standardized V(λ) function, which cannot be used in the UV range and leads to large errors when blue or red LEDs are measured in its wings, where the realization is always poor. Reference irradiance meters with spectrally constant response and high-intensity LED irradiance sources were developed here to implement the previously suggested broadband radiometric LED measurement procedure [1, 2]. Using a detector with spectrally constant response, the broadband radiometric quantities of any LEDs or LED groups can be simply measured with low uncertainty without using any source standard. The spectral flatness of filtered-Si detectors and low-noise pyroelectric radiometers are compared. Examples are given for integrated irradiance measurement of UV and blue LED sources using the here introduced reference (standard) pyroelectric irradiance meters. For validation, the broadband measured integrated irradiance of several LED-365 sources were compared with the spectrally determined integrated irradiance derived from an FEL spectral irradiance lamp-standard. Integrated responsivity transfer from the reference irradiance meter to transfer standard and field UV irradiance meters is discussed. PMID:28649167

Broadband Radiometric LED Measurements.

PubMed

Eppeldauer, G P; Cooksey, C C; Yoon, H W; Hanssen, L M; Podobedov, V B; Vest, R E; Arp, U; Miller, C C

2016-01-01

At present, broadband radiometric measurements of LEDs with uniform and low-uncertainty results are not available. Currently, either complicated and expensive spectral radiometric measurements or broadband photometric LED measurements are used. The broadband photometric measurements are based on the CIE standardized V(λ) function, which cannot be used in the UV range and leads to large errors when blue or red LEDs are measured in its wings, where the realization is always poor. Reference irradiance meters with spectrally constant response and high-intensity LED irradiance sources were developed here to implement the previously suggested broadband radiometric LED measurement procedure [1, 2]. Using a detector with spectrally constant response, the broadband radiometric quantities of any LEDs or LED groups can be simply measured with low uncertainty without using any source standard. The spectral flatness of filtered-Si detectors and low-noise pyroelectric radiometers are compared. Examples are given for integrated irradiance measurement of UV and blue LED sources using the here introduced reference (standard) pyroelectric irradiance meters. For validation, the broadband measured integrated irradiance of several LED-365 sources were compared with the spectrally determined integrated irradiance derived from an FEL spectral irradiance lamp-standard. Integrated responsivity transfer from the reference irradiance meter to transfer standard and field UV irradiance meters is discussed.

Landsat-7 Enhanced Thematic Mapper plus radiometric calibration

USGS Publications Warehouse

Markham, B.L.; Boncyk, Wayne C.; Helder, D.L.; Barker, J.L.

1997-01-01

Landsat-7 is currently being built and tested for launch in 1998. The Enhanced Thematic Mapper Plus (ETM+) sensor for Landsat-7, a derivative of the highly successful Thematic Mapper (TM) sensors on Landsats 4 and 5, and the Landsat-7 ground system are being built to provide enhanced radiometric calibration performance. In addition, regular vicarious calibration campaigns are being planned to provide additional information for calibration of the ETM+ instrument. The primary upgrades to the instrument include the addition of two solar calibrators: the full aperture solar calibrator, a deployable diffuser, and the partial aperture solar calibrator, a passive device that allows the ETM+ to image the sun. The ground processing incorporates for the first time an off-line facility, the Image Assessment System (IAS), to perform calibration, evaluation and analysis. Within the IAS, processing capabilities include radiometric artifact characterization and correction, radiometric calibration from the multiple calibrator sources, inclusion of results from vicarious calibration and statistical trending of calibration data to improve calibration estimation. The Landsat Product Generation System, the portion of the ground system responsible for producing calibrated products, will incorporate the radiometric artifact correction algorithms and will use the calibration information generated by the IAS. This calibration information will also be supplied to ground processing systems throughout the world.

Texture analysis of radiometric signatures of new sea ice forming in Arctic leads

NASA Technical Reports Server (NTRS)

Eppler, Duane T.; Farmer, L. Dennis

1991-01-01

Analysis of 33.6-GHz, high-resolution, passive microwave images suggests that new sea ice accumulating in open leads is characterized by a unique textural signature which can be used to discriminate new ice forming in this environment from adjacent surfaces of similar radiometric temperature. Ten training areas were selected from the data set, three of which consisted entirely of first-year ice, four entirely of multilayer ice, and three of new ice in open leads in the process of freezing. A simple gradient operator was used to characterize the radiometric texture in each training region in terms of the degree to which radiometric gradients are oriented. New ice in leads has a sufficiently high proportion of well-oriented features to distinguish it uniquely from first-year ice and multiyear ice. The predominance of well-oriented features probably reflects physical processes by which new ice accumulates in open leads. Banded structures, which are evident in aerial photographs of new ice, apparently give rise to the radiometric signature observed, in which the trend of brightness temperature gradients is aligned parallel to lead trends. First-year ice and multiyear ice, which have been subjected to a more random growth and process history, lack this banded structure and therefore are characterized by signatures in which well-aligned elements are less dominant.

Next-generation pushbroom filter radiometers for remote sensing

NASA Astrophysics Data System (ADS)

Tarde, Richard W.; Dittman, Michael G.; Kvaran, Geir E.

2012-09-01

Individual focal plane size, yield, and quality continue to improve, as does the technology required to combine these into large tiled formats. As a result, next-generation pushbroom imagers are replacing traditional scanning technologies in remote sensing applications. Pushbroom architecture has inherently better radiometric sensitivity and significantly reduced payload mass, power, and volume than previous generation scanning technologies. However, the architecture creates challenges achieving the required radiometric accuracy performance. Achieving good radiometric accuracy, including image spectral and spatial uniformity, requires creative optical design, high quality focal planes and filters, careful consideration of on-board calibration sources, and state-of-the-art ground test facilities. Ball Aerospace built the Landsat Data Continuity Mission (LDCM) next-generation Operational Landsat Imager (OLI) payload. Scheduled to launch in 2013, OLI provides imagery consistent with the historical Landsat spectral, spatial, radiometric, and geometric data record and completes the generational technology upgrade from the Enhanced Thematic Mapper (ETM+) whiskbroom technology to modern pushbroom technology afforded by advanced focal planes. We explain how Ball's capabilities allowed producing the innovative next-generational OLI pushbroom filter radiometer that meets challenging radiometric accuracy or calibration requirements. OLI will improve the multi-decadal land surface observation dataset dating back to the 1972 launch of ERTS-1 or Landsat 1.

Laboratory-based bidirectional reflectance distribution functions of radiometric tarps.

PubMed

Georgiev, Georgi T; Butler, James J

2008-06-20

Laboratory-based bidirectional reflectance distribution functions (BRDFs) of radiometric tarp samples used in the vicarious calibration of Earth remote sensing satellite instruments are presented in this paper. The results illustrate the BRDF dependence on the orientation of the tarps' weft and warp threads. The study was performed using the GSFC scatterometer at incident zenith angles of 0 degrees, 10 degrees, and 30 degrees; scatter zenith angles from 0 degrees to 60 degrees; and scatter azimuth angles of 0 degrees, 45 degrees, 90 degrees, 135 degrees, and 180 degrees. The wavelengths were 485 nm, 550 nm, 633 nm, and 800 nm. The tarp's weft and warp dependence on BRDF is well defined at all measurement geometries and wavelengths. The BRDF difference can be as high as 8% at 0 degrees incident angle and 12% at 30 degrees incident angle. The fitted BRDF data show a very small discrepancy from the measured ones. New data on the forward and backscatter properties of radiometric tarps are reported. The backward scatter is well pronounced for the white samples. The black sample has well-pronounced forward scatter. The provided BRDF characterization of radiometric tarps is an excellent reference for anyone interested in using tarps for radiometric calibrations. The results are NIST traceable.

Solar Tower Experiments for Radiometric Calibration and Validation of Infrared Imaging Assets and Analysis Tools for Entry Aero-Heating Measurements

NASA Technical Reports Server (NTRS)

Splinter, Scott C.; Daryabeigi, Kamran; Horvath, Thomas J.; Mercer, David C.; Ghanbari, Cheryl M.; Ross, Martin N.; Tietjen, Alan; Schwartz, Richard J.

2008-01-01

The NASA Engineering and Safety Center sponsored Hypersonic Thermodynamic Infrared Measurements assessment team has a task to perform radiometric calibration and validation of land-based and airborne infrared imaging assets and tools for remote thermographic imaging. The IR assets and tools will be used for thermographic imaging of the Space Shuttle Orbiter during entry aero-heating to provide flight boundary layer transition thermography data that could be utilized for calibration and validation of empirical and theoretical aero-heating tools. A series of tests at the Sandia National Laboratories National Solar Thermal Test Facility were designed for this task where reflected solar radiation from a field of heliostats was used to heat a 4 foot by 4 foot test panel consisting of LI 900 ceramic tiles located on top of the 200 foot tall Solar Tower. The test panel provided an Orbiter-like entry temperature for the purposes of radiometric calibration and validation. The Solar Tower provided an ideal test bed for this series of radiometric calibration and validation tests because it had the potential to rapidly heat the large test panel to spatially uniform and non-uniform elevated temperatures. Also, the unsheltered-open-air environment of the Solar Tower was conducive to obtaining unobstructed radiometric data by land-based and airborne IR imaging assets. Various thermocouples installed on the test panel and an infrared imager located in close proximity to the test panel were used to obtain surface temperature measurements for evaluation and calibration of the radiometric data from the infrared imaging assets. The overall test environment, test article, test approach, and typical test results are discussed.

Mechanically scanned deployable antenna study

NASA Technical Reports Server (NTRS)

1983-01-01

The conceptual design of a Mechanically Scanned Deployable Antenna which is launched by the STS (Space Shuttle) to provide radiometric brightness temperature maps of the Earth and oceans at selected frequency bands in the frequency range of 1.4 GHz to 11 GHz is presented. Unlike previous scanning radiometric systems, multiple radiometers for each frequency are required in order to fill in the resolution cells across the swath created by the 15 meter diameter spin stabilized system. This multiple beam radiometric system is sometimes designated as a ""whiskbroom'' system in that it combines the techniques of the scanning and ""pushbroom'' type systems. The definition of the feed system including possible feed elements and location, determination of the fundamental reflector feed offset geometry including offset angles and f/D ratio, preliminary estimates of the beam efficiency of the feed reflector system, a summary of reflector mesh losses at the proposed radiometric frequency bands, an overall conceptual configuration design and preliminary structural and thermal analyses are included.

Research on orbit prediction for solar-based calibration proper satellite

NASA Astrophysics Data System (ADS)

Chen, Xuan; Qi, Wenwen; Xu, Peng

2018-03-01

Utilizing the mathematical model of the orbit mechanics, the orbit prediction is to forecast the space target's orbit information of a certain time based on the orbit of the initial moment. The proper satellite radiometric calibration and calibration orbit prediction process are introduced briefly. On the basis of the research of the calibration space position design method and the radiative transfer model, an orbit prediction method for proper satellite radiometric calibration is proposed to select the appropriate calibration arc for the remote sensor and to predict the orbit information of the proper satellite and the remote sensor. By analyzing the orbit constraint of the proper satellite calibration, the GF-1solar synchronous orbit is chose as the proper satellite orbit in order to simulate the calibration visible durance for different satellites to be calibrated. The results of simulation and analysis provide the basis for the improvement of the radiometric calibration accuracy of the satellite remote sensor, which lays the foundation for the high precision and high frequency radiometric calibration.

Passive microwave sensing of soil moisture content: Soil bulk density and surface roughness

NASA Technical Reports Server (NTRS)

Wang, J. R.

1982-01-01

Microwave radiometric measurements over bare fields of different surface roughnesses were made at the frequencies of 1.4 GHz, 5 GHz, and 10.7 GHz to study the frequency dependence as well as the possible time variation of surface roughness. The presence of surface roughness was found to increase the brightness temperature of soils and reduce the slope of regression between brightness temperature and soil moisture content. The frequency dependence of the surface roughness effect was relatively weak when compared with that of the vegetation effect. Radiometric time series observation over a given field indicated that field surface roughness might gradually diminish with time, especially after a rainfall or irrigation. This time variation of surface roughness served to enhance the uncertainty in remote soil moisture estimate by microwave radiometry. Three years of radiometric measurements over a test site revealed a possible inconsistency in the soil bulk density determination, which turned out to be an important factor in the interpretation of radiometric data.

A Preliminary Analysis of LANDSAT-4 Thematic Mapper Radiometric Performance

NASA Technical Reports Server (NTRS)

Justice, C.; Fusco, L.; Mehl, W.

1985-01-01

The NASA raw (BT) product, the radiometrically corrected (AT) product, and the radiometrically and geometrically corrected (PT) product of a TM scene were analyzed examine the frequency distribution of the digital data; the statistical correlation between the bands; and the variability between the detectors within a band. The analyses were performed on a series of image subsets from the full scence. Results are presented from one 1024 c 1024 pixel subset of Realfoot Lake, Tennessee which displayed a representative range of ground conditions and cover types occurring within the full frame image. From this cursory examination of one of the first seven channel TM data sets, it would appear that the radiometric performance of the system is most satisfactory and largely meets pre-launch specifications. Problems were noted with Band 5 Detector 3 and Band 2 Detector 4. Differences were observed between forward and reverse scan detector responses both for the BT and AT products. No systematic variations were observed between odd and even detectors.

Passive microwave sensing of soil moisture content - The effects of soil bulk density and surface roughness

NASA Technical Reports Server (NTRS)

Wang, J. R.

1983-01-01

Microwave radiometric measurements over bare fields of different surface roughness were made at frequencies of 1.4 GHz, 5 GHz, and 10.7 GHz to study the frequency dependence, as well as the possible time variation, of surface roughness. An increase in surface roughness was found to increase the brightness temperature of soils and reduce the slope of regression between brightness temperature and soil moisture content. The frequency dependence of the surface roughness effect was relatively weak when compared with that of the vegetation effect. Radiometric time-series observations over a given field indicate that field surface roughness might gradually diminish with time, especially after a rainfall or irrigation. The variation of surface roughness increases the uncertainty of remote soil moisture estimates by microwave radiometry. Three years of radiometric measurements over a test site revealed a possible inconsistency in the soil bulk density determination, which is an important factor in the interpretation of radiometric data.

Automated geographic registration and radiometric correction for UAV-based mosaics

NASA Astrophysics Data System (ADS)

Thomasson, J. Alex; Shi, Yeyin; Sima, Chao; Yang, Chenghai; Cope, Dale A.

2017-05-01

Texas A and M University has been operating a large-scale, UAV-based, agricultural remote-sensing research project since 2015. To use UAV-based images in agricultural production, many high-resolution images must be mosaicked together to create an image of an agricultural field. Two key difficulties to science-based utilization of such mosaics are geographic registration and radiometric calibration. In our current research project, image files are taken to the computer laboratory after the flight, and semi-manual pre-processing is implemented on the raw image data, including ortho-mosaicking and radiometric calibration. Ground control points (GCPs) are critical for high-quality geographic registration of images during mosaicking. Applications requiring accurate reflectance data also require radiometric-calibration references so that reflectance values of image objects can be calculated. We have developed a method for automated geographic registration and radiometric correction with targets that are installed semi-permanently at distributed locations around fields. The targets are a combination of black (≍5% reflectance), dark gray (≍20% reflectance), and light gray (≍40% reflectance) sections that provide for a transformation of pixel-value to reflectance in the dynamic range of crop fields. The exact spectral reflectance of each target is known, having been measured with a spectrophotometer. At the time of installation, each target is measured for position with a real-time kinematic GPS receiver to give its precise latitude and longitude. Automated location of the reference targets in the images is required for precise, automated, geographic registration; and automated calculation of the digital-number to reflectance transformation is required for automated radiometric calibration. To validate the system for radiometric calibration, a calibrated UAV-based image mosaic of a field was compared to a calibrated single image from a manned aircraft. Reflectance values in selected zones of each image were strongly linearly related, and the average error of UAV-mosaic reflectances was 3.4% in the red band, 1.9% in the green band, and 1.5% in the blue band. Based on these results, the proposed physical system and automated software for calibrating UAV mosaics show excellent promise.

Are the World's Oceans Optically Different?

NASA Technical Reports Server (NTRS)

Szeto, M.; Werdell, P. J.; Moore, T. S.; Campbell, J. W.

2011-01-01

Regional differences in the Sea-viewing Wide Field-of-view Sensor chlorophyll algorithm uncertainty were observed in a large global data set containing coincident in situ measurements of chlorophyll a concentration (Chla) and spectral radiometry. The uncertainty was found to be systematic when the data were sorted by ocean: Atlantic, Pacific, Southern, and Indian Oceans. Artifacts associated with different instrumentation and analytical methods had been previously ruled out. Given these oceanic biases in the chlorophyll algorithm, we hypothesized that the oceans may be optically different, and their optical differences may be intrinsically related to regional differences in phytoplankton community structure or biogeochemical processes. The oceanic biases, originally observed using radiometric measurements, were independently verified using total absorption measurements in a subset of the data. Moreover, they were explained through oceanic differences in the absorption of colored detrital matter (CDM) and phytoplankton. Both effects were considered together in explaining the ocean biases through a stepwise linear regression analysis. Significant oceanic differences in the amount of CDM and in phytoplankton cell sizes and pigmentation would give rise to optical differences, but we raise a concern for the spatial coverage of the data. We do not suggest the application of ocean-based algorithms but rather emphasize the importance of consolidating regional data sets before reaching this conclusion.

Imager for Mars Pathfinder (IMP) image calibration

USGS Publications Warehouse

Reid, R.J.; Smith, P.H.; Lemmon, M.; Tanner, R.; Burkland, M.; Wegryn, E.; Weinberg, J.; Marcialis, R.; Britt, D.T.; Thomas, N.; Kramm, R.; Dummel, A.; Crowe, D.; Bos, B.J.; Bell, J.F.; Rueffer, P.; Gliem, F.; Johnson, J. R.; Maki, J.N.; Herkenhoff, K. E.; Singer, Robert B.

1999-01-01

The Imager for Mars Pathfinder returned over 16,000 high-quality images from the surface of Mars. The camera was well-calibrated in the laboratory, with <5% radiometric uncertainty. The photometric properties of two radiometric targets were also measured with 3% uncertainty. Several data sets acquired during the cruise and on Mars confirm that the system operated nominally throughout the course of the mission. Image calibration algorithms were developed for landed operations to correct instrumental sources of noise and to calibrate images relative to observations of the radiometric targets. The uncertainties associated with these algorithms as well as current improvements to image calibration are discussed. Copyright 1999 by the American Geophysical Union.

All-digital precision processing of ERTS images

NASA Technical Reports Server (NTRS)

Bernstein, R. (Principal Investigator)

1975-01-01

The author has identified the following significant results. Digital techniques have been developed and used to apply precision-grade radiometric and geometric corrections to ERTS MSS and RBV scenes. Geometric accuracies sufficient for mapping at 1:250,000 scale have been demonstrated. Radiometric quality has been superior to ERTS NDPF precision products. A configuration analysis has shown that feasible, cost-effective all-digital systems for correcting ERTS data are easily obtainable. This report contains a summary of all results obtained during this study and includes: (1) radiometric and geometric correction techniques, (2) reseau detection, (3) GCP location, (4) resampling, (5) alternative configuration evaluations, and (6) error analysis.

Summary of the Flight Technology Improvement Workshop. [spaceborne optical radiometric instruments, attitude control, and electromechanical and power subsystems

NASA Technical Reports Server (NTRS)

1979-01-01

Spaceborne instrumentation technology deficiencies are summarized. Recommendations are given for technology development, improvements in existing technology, and policy changes needed to facilitate the use of improved technology. Optical radiometric instruments, attitude control, and electromechanical and power subsystems are considered.

Correction to Method of Establishing the Absolute Radiometric Accuracy of Remote Sensing Systems While On-orbit Using Characterized Stellar Sources

NASA Technical Reports Server (NTRS)

Bowen, Howard S.; Cunningham, Douglas M.

2007-01-01

The contents include: 1) Brief history of related events; 2) Overview of original method used to establish absolute radiometric accuracy of remote sensing instruments using stellar sources; and 3) Considerations to improve the stellar calibration approach.

Validating the MISR radiometric scale for the ocean aerosol science communities

NASA Technical Reports Server (NTRS)

Bruegge, Carol J.; Abdou, Wedad; Diner, David J.; Gaitley, Barbara; Helmlinger, Mark; Kahn, Ralph; Martonchik, John V.

2004-01-01

This paper validates that radiometric accuracy is maintained throughout the dynamic range of the instrument. As part of this study, a new look has been taken on the band-relative scale, and a decrease in the radiance reported for the Red and NIR Bands has resulted.

Ellipsoidal geometry in asteroid thermal models - The standard radiometric model

NASA Technical Reports Server (NTRS)

Brown, R. H.

1985-01-01

The major consequences of ellipsoidal geometry in an othewise standard radiometric model for asteroids are explored. It is shown that for small deviations from spherical shape a spherical model of the same projected area gives a reasonable aproximation to the thermal flux from an ellipsoidal body. It is suggested that large departures from spherical shape require that some correction be made for geometry. Systematic differences in the radii of asteroids derived radiometrically at 10 and 20 microns may result partly from nonspherical geometry. It is also suggested that extrapolations of the rotational variation of thermal flux from a nonspherical body based solely on the change in cross-sectional area are in error.

DIGITAL CARTOGRAPHY OF THE PLANETS: NEW METHODS, ITS STATUS, AND ITS FUTURE.

USGS Publications Warehouse

Batson, R.M.

1987-01-01

A system has been developed that establishes a standardized cartographic database for each of the 19 planets and major satellites that have been explored to date. Compilation of the databases involves both traditional and newly developed digital image processing and mosaicking techniques, including radiometric and geometric corrections of the images. Each database, or digital image model (DIM), is a digital mosaic of spacecraft images that have been radiometrically and geometrically corrected and photometrically modeled. During compilation, ancillary data files such as radiometric calibrations and refined photometric values for all camera lens and filter combinations and refined camera-orientation matrices for all images used in the mapping are produced.

Target contrast considerations in millimeter wave radiometry for airborne navigation

NASA Technical Reports Server (NTRS)

Mayer, A.

1971-01-01

Target signal requirements for aircraft navigation systems that use radiometric receivers which map thermally emitted power radiated by terrain or power radiated by ground-based beacons are discussed. For selected millimeter wavelength bands, microwaves suffer relatively little degradation by absorption or scattering on passage through the atmosphere, despite extreme weather variations. Interest centers on 8-millimeter waves because of component availability, portability (small size), high image resolution, and all-weather capability at this wavelength. The idea of radiometric airborne navigation is introduced. Elements of radiometry, terrain radiation, and atmospheric transmission characteristics are reviewed. Data pertaining to these elements at 8 mm wavelength are collected. Calculation of radiometric contrasts is discussed for some simple models of terrain targets.

Radiometric Method for the Detection of Coliform Organisms in Water

PubMed Central

Bachrach, Uriel; Bachrach, Zelilah

1974-01-01

A new radiometric method for the detection of coliform bacteria in water has been described. The method is based on the release of 14CO2 from [14C]lactose by bacteria suspended in growth medium and incubated at 37 C. The evolved 14CO2 is trapped by hyamine hydroxide and counted in a liquid scintillation spectrometer. The method permits the detection of 1 to 10 organisms within 6 h of incubation. Coliform bacteria suspended in water for several days recover from starvation and may be quantitated by the proposed method. Bacteria from water samples may also be concentrated by filtration through membrane filters and detected by the radiometric assay. PMID:4605007

An equivalent method of mixed dielectric constant in passive microwave/millimeter radiometric measurement

NASA Astrophysics Data System (ADS)

Su, Jinlong; Tian, Yan; Hu, Fei; Gui, Liangqi; Cheng, Yayun; Peng, Xiaohui

2017-10-01

Dielectric constant is an important role to describe the properties of matter. This paper proposes This paper proposes the concept of mixed dielectric constant(MDC) in passive microwave radiometric measurement. In addition, a MDC inversion method is come up, Ratio of Angle-Polarization Difference(RAPD) is utilized in this method. The MDC of several materials are investigated using RAPD. Brightness temperatures(TBs) which calculated by MDC and original dielectric constant are compared. Random errors are added to the simulation to test the robustness of the algorithm. Keywords: Passive detection, microwave/millimeter, radiometric measurement, ratio of angle-polarization difference (RAPD), mixed dielectric constant (MDC), brightness temperatures, remote sensing, target recognition.

LANDSAT-D data format control book. Volume 6, appendix D: Thematic mapper Computer Compatible Tape (CCT-AT/PT)

NASA Technical Reports Server (NTRS)

Ahmed, H.

1981-01-01

The format of computer compatible tapes which contain LANDSAT 4 and D Prime thematic mapper data is defined. A complete specification of the CCT-AT (radiometric corrections applied and geometric matrices appended) and the CCT-PT (radiometric and geometric corrections) data formats is provided.

Space Object Radiometric Modeling for Hardbody Optical Signature Database Generation

DTIC Science & Technology

2009-09-01

Introduction This presentation summarizes recent activity in monitoring spacecraft health status using passive remote optical nonimaging ...Approved for public release; distribution is unlimited. Space Object Radiometric Modeling for Hardbody Optical Signature Database Generation...It is beneficial to the observer/analyst to understand the fundamental optical signature variability associated with these detection and

EREP geothermal. [northern California

NASA Technical Reports Server (NTRS)

Johnston, E. W. (Principal Investigator); Dunklee, A. L.; Wychgram, D. C.

1974-01-01

The author has identified the following significant results. A reasonably good agreement was found for the radiometric temperatures calculated from the ground truth data and the radiometric temperatures measured by the S192 scanner. This study showed that the S192 scanner data could be used to create good thermal images, particularly with the x-5 detector array.

Tracking and Data Relay Satellite System (TDRSS) navigation with DSN radio metric data

NASA Technical Reports Server (NTRS)

Ellis, J.

1981-01-01

The use of DSN radiometric data for enhancing the orbit determination capability for TDRS is examined. Results of a formal covariance analysis are presented which establish the nominal TDRS navigation performance and assess the performance improvement based on augmenting the nominal TDRS data strategy with radiometric data from DSN sites.

Calibration of passive remote observing optical and microwave instrumentation; Proceedings of the Meeting, Orlando, FL, Apr. 3-5, 1991

NASA Technical Reports Server (NTRS)

Guenther, Bruce W. (Editor)

1991-01-01

Various papers on the calibration of passive remote observing optical and microwave instrumentation are presented. Individual topics addressed include: on-board calibration device for a wide field-of-view instrument, calibration for the medium-resolution imaging spectrometer, cryogenic radiometers and intensity-stabilized lasers for EOS radiometric calibrations, radiometric stability of the Shuttle-borne solar backscatter ultraviolet spectrometer, ratioing radiometer for use with a solar diffuser, requirements of a solar diffuser and measurements of some candidate materials, reflectance stability analysis of Spectralon diffuse calibration panels, stray light effects on calibrations using a solar diffuser, radiometric calibration of SPOT 23 HRVs, surface and aerosol models for use in radiative transfer codes. Also addressed are: calibrated intercepts for solar radiometers used in remote sensor calibration, radiometric calibration of an airborne multispectral scanner, in-flight calibration of a helicopter-mounted Daedalus multispectral scanner, technique for improving the calibration of large-area sphere sources, remote colorimetry and its applications, spatial sampling errors for a satellite-borne scanning radiometer, calibration of EOS multispectral imaging sensors and solar irradiance variability.

Study on radiometric consistency of LANDSAT-4 multispectral scanner. [borders between North and South Carolina and between the Imperial Valley of California and Mexico

NASA Technical Reports Server (NTRS)

Malila, W. A. (Principal Investigator)

1983-01-01

Two full frames of radiometrically corrected LANDSAT-4 MSS data were examined to determine a number of radiometric properties. It was found that LANDSAT-4 MSS produces data of good quality with dynamic ranges and target responses qualitatively similar to those of previous MSS sensors. Banding appears to be quite well corrected, with a residual rms error of about 0.3 digital counts being measured; the histogram equalization algorithm appears to be working as advertised. A low level coherent noise effect was found in all bands, appearing in uniform areas as a diagonal striping pattern. The principle component of this noise was found by Fourier analysis to be a highly consistent wavelength of 3.6 pixels along a scan line (28 KHz). The magnitude of this effect ranged from about 0.75 of one count in the worst band (Band 1) to only about 0.25 counts in the best band (Band 4). Preparations were made for establishing a relative radiometric calibration from MSS 4 data with respect to MSS 3.

Radiometric assessment method for diffraction effects in hyperspectral imagers applied to the earth explorer #8 mission candidate flex

NASA Astrophysics Data System (ADS)

Berlich, R.; Harnisch, B.

2017-11-01

An accurate stray light analysis represents a crucial part in the early design phase of hyperspectral imaging systems, since scattering effects can severely limit the radiometric accuracy performance. In addition to conventional contributors including ghost images and surface scattering, i.e. caused by a residual surface micro-roughness and particle contamination, diffraction effects can result in significant radiometric errors in the spatial and spectral domain of pushbroom scanners. In this paper, we present a mathematical approach that efficiently evaluates these diffraction effects based on a Fourier analysis. It is shown that considering the conventional diffraction at the systems entrance pupil only, significantly overestimates the stray light contribution. In fact, a correct assessment necessitates taking into account the joint influence of the entrance pupil, the spectrometer slit as well as the dispersion element. We quantitatively investigate the corresponding impact on the Instrument Spectral Response Function (ISRF) of the Earth Explorer #8 Mission Candidate FLEX and analyse the expected radiometric error distribution for a typical earth observation scenario requirement.

Classification of Dual-Wavelength Airborne Laser Scanning Point Cloud Based on the Radiometric Properties of the Objects

NASA Astrophysics Data System (ADS)

Pilarska, M.

2018-05-01

Airborne laser scanning (ALS) is a well-known and willingly used technology. One of the advantages of this technology is primarily its fast and accurate data registration. In recent years ALS is continuously developed. One of the latest achievements is multispectral ALS, which consists in obtaining simultaneously the data in more than one laser wavelength. In this article the results of the dual-wavelength ALS data classification are presented. The data were acquired with RIEGL VQ-1560i sensor, which is equipped with two laser scanners operating in different wavelengths: 532 nm and 1064 nm. Two classification approaches are presented in the article: classification, which is based on geometric relationships between points and classification, which mostly relies on the radiometric properties of registered objects. The overall accuracy of the geometric classification was 86 %, whereas for the radiometric classification it was 81 %. As a result, it can be assumed that the radiometric features which are provided by the multispectral ALS have potential to be successfully used in ALS point cloud classification.

Radiometric resolution enhancement by lossy compression as compared to truncation followed by lossless compression

NASA Technical Reports Server (NTRS)

Tilton, James C.; Manohar, Mareboyana

1994-01-01

Recent advances in imaging technology make it possible to obtain imagery data of the Earth at high spatial, spectral and radiometric resolutions from Earth orbiting satellites. The rate at which the data is collected from these satellites can far exceed the channel capacity of the data downlink. Reducing the data rate to within the channel capacity can often require painful trade-offs in which certain scientific returns are sacrificed for the sake of others. In this paper we model the radiometric version of this form of lossy compression by dropping a specified number of least significant bits from each data pixel and compressing the remaining bits using an appropriate lossless compression technique. We call this approach 'truncation followed by lossless compression' or TLLC. We compare the TLLC approach with applying a lossy compression technique to the data for reducing the data rate to the channel capacity, and demonstrate that each of three different lossy compression techniques (JPEG/DCT, VQ and Model-Based VQ) give a better effective radiometric resolution than TLLC for a given channel rate.

Preliminary radiometric calibration assessment of ALOS AVNIR-2

USGS Publications Warehouse

Bouvet, M.; Goryl, P.; Chander, G.; Santer, R.; Saunier, S.

2008-01-01

This paper summarizes the activities carried out in the frame of the data quality activities of the Advanced Visible and Near Infrared Radiometer type 2 (AVNIR-2) sensor onboard the Advanced Land Observing Satellite (ALOS). Assessment of the radiometric calibration of the AVNIR-2 multi-spectral imager is achieved via three intercomparisons to currently flying sensors over the Libyan desert, during the first year of operation. AU three methodologies indicate a slight underestimation of AVNIR-2 in band 1 by 4 to 7% with respect to other sensors radiometric scale. Band 2 does not show any obvious bias. Results for band 3 are affected by saturation due to inappropriate gain setting. Two methodologies indicate no significant bias in band 4. Preliminary results indicate possible degradations of the AVNIR-2 channels, which, when modeled as an exponentially decreasing functions, have time constants of respectively 13.2 %.year-1, 8.8%.year-1 and 0.1%.year-1 in band 1, 2 and 4 (with respect to the radiometric scale of the MEdium Resolution Imaging Spectrometer, MERIS). Longer time series of AVNIR-2 data are needed to draw final conclusions. ?? 2007 IEEE.

Radiometric age map of Aleutian Islands

USGS Publications Warehouse

Wilson, Frederic H.; Turner, D.L.

1975-01-01

This map includes published, thesis, and open-file radiometric data available to us as of June, 1975. Some dates are not plotted because of inadequate location data in the original references.The map is divided into five sections, based on 1:1,000,000 scale enlargements of the National Atlas maps of Alaska. Within each section (e.g., southeastern Alaska), radiometric dates are plotted and keyed to 1:250,000 scale quadrangles. Accompanying each map section is table 1, listing map numbers and the sample identification numbers used in DGGS Special Report 10: Radiometric Dates from Alaska-A 1975 Compilation”. The reader is referred to Special Report 10 for more complete information on location, rock type, dating method, and literature references for each age entry. A listing of dates in Special Report lo which require correction or deletion is included S table 2. Corrected and additional entries are listed in table 3. The listings in tables 2 and 3 follow the format of Special Report 10. Table 4 is a glossary of abbreviations used for quadrangle name, rock type, mineral dated, and type of dating method used.

Radiometric age map of southcentral Alaska

USGS Publications Warehouse

Wilson, Frederic H.; Turner, D.L.

1975-01-01

This map includes published, thesis, and open-file radiometric data available to us as of June, 1975. Some dates are not plotted because of inadequate location data in the original references.The map is divided into five sections, based on 1:1,000,000 scale enlargements of the National Atlas maps of Alaska. Within each section (e.g., southeastern Alaska), radiometric dates are plotted and keyed to 1:250,000 scale quadrangles. Accompanying each map section is table 1, listing map numbers and the sample identification numbers used in DGGS Special Report 10: Radiometric Dates from Alaska-A 1975 Compilation”. The reader is referred to Special Report 10 for more complete information on location, rock type, dating method, and literature references for each age entry. A listing of dates in Special Report lo which require correction or deletion is included S table 2. Corrected and additional entries are listed in table 3. The listings in tables 2 and 3 follow the format of Special Report 10. Table 4 is a glossary of abbreviations used for quadrangle name, rock type, mineral dated, and type of dating method used.

Radiometric age map of southwest Alaska

USGS Publications Warehouse

Wilson, Frederic H.; Turner, D.L.

1975-01-01

This map includes published, thesis, and open-file radiometric data available to us as of June, 1975. Some dates are not plotted because of inadequate location data in the original references.The map is divided into five sections, based on 1:1,000,000 scale enlargements of the National Atlas maps of Alaska. Within each section (e.g., southeastern Alaska), radiometric dates are plotted and keyed to 1:250,000 scale quadrangles. Accompanying each map section is table 1, listing map numbers and the sample identification numbers used in DGGS Special Report 10: Radiometric Dates from Alaska-A 1975 Compilation”. The reader is referred to Special Report 10 for more complete information on location, rock type, dating method, and literature references for each age entry. A listing of dates in Special Report lo which require correction or deletion is included S table 2. Corrected and additional entries are listed in table 3. The listings in tables 2 and 3 follow the format of Special Report 10. Table 4 is a glossary of abbreviations used for quadrangle name, rock type, mineral dated, and type of dating method used.

Radiometric age map of southeast Alaska

USGS Publications Warehouse

Wilson, Frederic H.; Turner, D.L.

1975-01-01

This map includes published, thesis, and open-file radiometric data available to us as of June, 1975. Some dates are not plotted because of inadequate location data in the original references.The map is divided into five sections, based on 1:1,000,000 scale enlargements of the National Atlas maps of Alaska. Within each section (e.g., southeastern Alaska), radiometric dates are plotted and keyed to 1:250,000 scale quadrangles. Accompanying each map section is table 1, listing map numbers and the sample identification numbers used in DGGS Special Report 10: Radiometric Dates from Alaska-A 1975 Compilation”. The reader is referred to Special Report 10 for more complete information on location, rock type, dating method, and literature references for each age entry. A listing of dates in Special Report lo which require correction or deletion is included S table 2. Corrected and additional entries are listed in table 3. The listings in tables 2 and 3 follow the format of Special Report 10. Table 4 is a glossary of abbreviations used for quadrangle name, rock type, mineral dated, and type of dating method used.

Radiometric age map of northern Alaska

USGS Publications Warehouse

Wilson, Frederic H.; Turner, D.L.

1975-01-01

This map includes published, thesis, and open-file radiometric data available to us as of June, 1975. Some dates are not plotted because of inadequate location data in the original references.The map is divided into five sections, based on 1:1,000,000 scale enlargements of the National Atlas maps of Alaska. Within each section (e.g., southeastern Alaska), radiometric dates are plotted and keyed to 1:250,000 scale quadrangles. Accompanying each map section is table 1, listing map numbers and the sample identification numbers used in DGGS Special Report 10: Radiometric Dates from Alaska-A 1975 Compilation”. The reader is referred to Special Report 10 for more complete information on location, rock type, dating method, and literature references for each age entry. A listing of dates in Special Report lo which require correction or deletion is included S table 2. Corrected and additional entries are listed in table 3. The listings in tables 2 and 3 follow the format of Special Report 10. Table 4 is a glossary of abbreviations used for quadrangle name, rock type, mineral dated, and type of dating method used.

Application of side-oblique image-motion blur correction to Kuaizhou-1 agile optical images.

PubMed

Sun, Tao; Long, Hui; Liu, Bao-Cheng; Li, Ying

2016-03-21

Given the recent development of agile optical satellites for rapid-response land observation, side-oblique image-motion (SOIM) detection and blur correction have become increasingly essential for improving the radiometric quality of side-oblique images. The Chinese small-scale agile mapping satellite Kuaizhou-1 (KZ-1) was developed by the Harbin Institute of Technology and launched for multiple emergency applications. Like other agile satellites, KZ-1 suffers from SOIM blur, particularly in captured images with large side-oblique angles. SOIM detection and blur correction are critical for improving the image radiometric accuracy. This study proposes a SOIM restoration method based on segmental point spread function detection. The segment region width is determined by satellite parameters such as speed, height, integration time, and side-oblique angle. The corresponding algorithms and a matrix form are proposed for SOIM blur correction. Radiometric objective evaluation indices are used to assess the restoration quality. Beijing regional images from KZ-1 are used as experimental data. The radiometric quality is found to increase greatly after SOIM correction. Thus, the proposed method effectively corrects image motion for KZ-1 agile optical satellites.

Laboratory-Based BRDF Calibration of Radiometric Tarps

NASA Technical Reports Server (NTRS)

Georgiev, Georgi T.; Butler, James J.

2007-01-01

The current study provides the remote sensing community with important high accuracy laboratory-based BRDF calibration of radiometric tarps. The results illustrate the dependence of tarps' weft and warp threads orientation on BRDF. The study was done at incident angles of 0deg, 10deg, and 30deg; scatter zenith angles from 0deg to 60deg, and scatter azimuth angles of 0deg, 45deg, 90deg, 135deg, and 180deg. The wavelengths were 485nm, 550nm, 633nm and 800nm. The dependence is well defined at all measurement geometries and wavelengths. It can be as high as 8% at 0deg incident angle and 2% at 30deg incident angle. The fitted BRDF data show a very small discrepancy from the measured ones. New data on the forward and backscatter properties of radiometric tarps is reported. The backward scatter is well pronounced for the white samples. The black sample has well pronounced forward scatter. The BRDF characterization of radiometric tarps can be successfully extended to other structured surface fabric samples. The results are NIST traceable.

Melanoma thickness measurement in two-layer tissue phantoms using pulsed photothermal radiometry (PPTR)

NASA Astrophysics Data System (ADS)

Wang, Tianyi; Qiu, Jinze; Paranjape, Amit; Milner, Thomas E.

2009-02-01

Melanoma is a malignant tumor of melanocytes which are found predominantly in skin. Melanoma is one of the rarer types of skin cancer but causes the majority of skin cancer related deaths. The staging of malignant melanoma using Breslow thickness is important because of the relationship to survival rate after five years. Pulsed photothermal radiometry (PPTR) is based on the time-resolved acquisition of infrared (IR) emission from a sample after pulsed laser exposure. PPTR can be used to investigate the relationship between melanoma thickness and detected radiometric temperature using two-layer tissue phantoms. We used a Monte Carlo simulation to mimic light transport in melanoma and employed a three-dimensional heat transfer model to obtain simulated radiometric temperature increase and, in comparison, we also conducted PPTR experiments to confirm our simulation results. Simulation and experimental results show similar trends: thicker absorbing layers corresponding to deeper lesions produce slower radiometric temperature decays. A quantitative relationship exists between PPTR radiometric temperature decay time and thickness of the absorbing layer in tissue phantoms.

Revised landsat-5 thematic mapper radiometric calibration

USGS Publications Warehouse

Chander, G.; Markham, B.L.; Barsi, J.A.

2007-01-01

Effective April 2, 2007, the radiometric calibration of Landsat-5 (L5) Thematic Mapper (TM) data that are processed and distributed by the U.S. Geological Survey (USGS) Center for Earth Resources Observation and Science (EROS) will be updated. The lifetime gain model that was implemented on May 5, 2003, for the reflective bands (1-5, 7) will be replaced by a new lifetime radiometric-calibration curve that is derived from the instrument's response to pseudoinvariant desert sites and from cross calibration with the Landsat-7 (L7) Enhanced TM Plus (ETM+). Although this calibration update applies to all archived and future L5 TM data, the principal improvements in the calibration are for the data acquired during the first eight years of the mission (1984-1991), where the changes in the instrument-gain values are as much as 15%. The radiometric scaling coefficients for bands 1 and 2 for approximately the first eight years of the mission have also been changed. Users will need to apply these new coefficients to convert the calibrated data product digital numbers to radiance. The scaling coefficients for the other bands have not changed.

A Digital Sensor Simulator of the Pushbroom Offner Hyperspectral Imaging Spectrometer

PubMed Central

Tao, Dongxing; Jia, Guorui; Yuan, Yan; Zhao, Huijie

2014-01-01

Sensor simulators can be used in forecasting the imaging quality of a new hyperspectral imaging spectrometer, and generating simulated data for the development and validation of the data processing algorithms. This paper presents a novel digital sensor simulator for the pushbroom Offner hyperspectral imaging spectrometer, which is widely used in the hyperspectral remote sensing. Based on the imaging process, the sensor simulator consists of a spatial response module, a spectral response module, and a radiometric response module. In order to enhance the simulation accuracy, spatial interpolation-resampling, which is implemented before the spatial degradation, is developed to compromise the direction error and the extra aliasing effect. Instead of using the spectral response function (SRF), the dispersive imaging characteristics of the Offner convex grating optical system is accurately modeled by its configuration parameters. The non-uniformity characteristics, such as keystone and smile effects, are simulated in the corresponding modules. In this work, the spatial, spectral and radiometric calibration processes are simulated to provide the parameters of modulation transfer function (MTF), SRF and radiometric calibration parameters of the sensor simulator. Some uncertainty factors (the stability, band width of the monochromator for the spectral calibration, and the integrating sphere uncertainty for the radiometric calibration) are considered in the simulation of the calibration process. With the calibration parameters, several experiments were designed to validate the spatial, spectral and radiometric response of the sensor simulator, respectively. The experiment results indicate that the sensor simulator is valid. PMID:25615727

Analysis of a commercial small unmanned airborne system (sUAS) in support of the Radiometric Calibration Test Site (RadCaTS) at Railroad Valley

NASA Astrophysics Data System (ADS)

Czapla-Myers, Jeffrey S.; Anderson, Nikolaus J.

2017-09-01

The Radiometric Calibration Test Site (RadCaTS) is an automated facility developed by the Remote Sensing Group (RSG) at the University of Arizona to provide radiometric calibration data for airborne and satellite sensors. RadCaTS uses stationary ground-viewing radiometers (GVRs) to spatially sample the surface reflectance of the site. The number and location of the GVRs is based on previous spatial, spectral, and temporal analyses of Railroad Valley. With the increase in high-resolution satellite sensors, there is renewed interest in examining the spatial uniformity the 1-km2 RadCaTS area at scales smaller than a typical 30-m sensor. RadCaTS is one of the four instrumented sites currently in the CEOS WGCV Radiometric Calibration Network (RadCalNet), which aims to harmonize the post-launch radiometric calibration of satellite sensors through the use of a global network of automated calibration sites. A better understanding of the RadCaTS spatial uniformity as a function of pixel size will also benefit the RadCalNet work. RSG has recently acquired a commercially-available small unmanned airborne system (sUAS) system, with which preliminary spatial homogeneity measurements of the 1-km2 RadCaTS area were made. This work describes an initial assessment of the airborne platform and integrated camera for spatial studies of RadCaTS using data that were collected in 2016 and 2017.

Changes in the Radiometric Sensitivity of SeaWiFS

NASA Technical Reports Server (NTRS)

McClain, Charles R.; Barnes, Robert A.; Eplee, Robert E., Jr.; Patt, Frederick S.

1998-01-01

We report on the lunar and solar measurements used to determine the changes in the radiometric sensitivity of the Sea-viewing Wide Field-of-view Sensor (SeaWiFS). Radiometric sensitivity is defined as the output from the instrument (or from one of the instrument bands) per unit spectral radiance at the instrument's input aperture. Knowledge of the long-term repeatability of the SeaWiFS measurements is crucial to maintaining the quality of the ocean scenes derived from measurements by the instrument. For SeaWiFS bands 1 through 6 (412 nm through 670 rim), the change in radiometric sensitivity is less than 0.2% for the period from November 1997 through November 1998. For band 7 (765 nm), the change is about 1.5%, and for band 8 (865 nm) about 5%. The rates of change of bands 7 and 8, which were linear with time for the first eight months of lunar measurements, are now slowing. The scatter in the data points about the trend lines in this analysis is less than 0.3% for all eight SeaWiFS bands. These results are based on monthly measurements of the moon. Daily solar measurements using an onboard diffuser show that the radiometric sensitivities of the SeaWiFS bands have changed smoothly during the time intervals between lunar measurements. Since SeaWiFS measurements have continued past November 1998, the results presented here are considered as a snapshot of the instrument performance as of that date.

CRISM Multispectral and Hyperspectral Mapping Data - A Global Data Set for Hydrated Mineral Mapping

NASA Astrophysics Data System (ADS)

Seelos, F. P.; Hash, C. D.; Murchie, S. L.; Lim, H.

2017-12-01

The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) is a visible through short-wave infrared hyperspectral imaging spectrometer (VNIR S-detector: 364-1055 nm; IR L-detector: 1001-3936 nm; 6.55 nm sampling) that has been in operation on the Mars Reconnaissance Orbiter (MRO) since 2006. Over the course of the MRO mission, CRISM has acquired 290,000 individual mapping observation segments (mapping strips) with a variety of observing modes and data characteristics (VNIR/IR; 100/200 m/pxl; multi-/hyper-spectral band selection) over a wide range of observing conditions (atmospheric state, observation geometry, instrument state). CRISM mapping data coverage density varies primarily with latitude and secondarily due to seasonal and operational considerations. The aggregate global IR mapping data coverage currently stands at 85% ( 80% at the equator with 40% repeat sampling), which is sufficient spatial sampling density to support the assembly of empirically optimized radiometrically consistent mapping mosaic products. The CRISM project has defined a number of mapping mosaic data products (e.g. Multispectral Reduced Data Record (MRDR) map tiles) with varying degrees of observation-specific processing and correction applied prior to mosaic assembly. A commonality among the mosaic products is the presence of inter-observation radiometric discrepancies which are traceable to variable observation circumstances or associated atmospheric/photometric correction residuals. The empirical approach to radiometric reconciliation leverages inter-observation spatial overlaps and proximal relationships to construct a graph that encodes the mosaic structure and radiometric discrepancies. The graph theory abstraction allows the underling structure of the msaic to be evaluated and the corresponding optimization problem configured so it is well-posed. Linear and non-linear least squares optimization is then employed to derive a set of observation- and wavelength- specific model parameters for a series of transform functions that minimize the total radiometric discrepancy across the mosaic. This empirical approach to CRISM data radiometric reconciliation and the utility of the resulting mapping data mosaic products for hydrated mineral mapping will be presented.

ASD FieldSpec Calibration Setup and Techniques

NASA Technical Reports Server (NTRS)

Olive, Dan

2001-01-01

This paper describes the Analytical Spectral Devices (ASD) Fieldspec Calibration Setup and Techniques. The topics include: 1) ASD Fieldspec FR Spectroradiometer; 2) Components of Calibration; 3) Equipment list; 4) Spectral Setup; 5) Spectral Calibration; 6) Radiometric and Linearity Setup; 7) Radiometric setup; 8) Datadets Required; 9) Data files; and 10) Field of View Measurement. This paper is in viewgraph form.

Radiometric calibration of an ultra-compact microbolometer thermal imaging module

NASA Astrophysics Data System (ADS)

Riesland, David W.; Nugent, Paul W.; Laurie, Seth; Shaw, Joseph A.

2017-05-01

As microbolometer focal plane array formats are steadily decreasing, new challenges arise in correcting for thermal drift in the calibration coefficients. As the thermal mass of the cameras decrease the focal plane becomes more sensitive to external thermal inputs. This paper shows results from a temperature compensation algorithm for characterizing and radiometrically calibrating a FLIR Lepton camera.

Revised radiometric calibration technique for LANDSAT-4 Thematic Mapper data by the Canada Centre for Remote Sensing

NASA Technical Reports Server (NTRS)

Murphy, J.; Butlin, T.; Duff, P.; Fitzgerald, A.

1984-01-01

Observations of raw image data, raw radiometric calibration data, and background measurements extracted from the raw data streams on high density tape reveal major shortcomings in a technique proposed by the Canadian Center for Remote Sensing in 1982 for the radiometric correction of TM data. Results are presented which correlate measurements of the DC background with variations in both image data background and calibration samples. The effect on both raw data and data corrected using the earlier proposed technique is explained and the correction required for these factors as a function of individual scan line number for each detector is described. How the revised technique can be incorporated into an operational environment is demonstrated.

Characterization of radiometric calibration of LANDSAT-4 TM reflective bands

NASA Technical Reports Server (NTRS)

Barker, J. L.; Abrams, R. B.; Ball, D. L.; Leung, K. C.

1984-01-01

Prelaunch and postlaunch internal calibrator, image, and background data is to characterize the radiometric performance of the LANDSAT-4 TM and to recommend improved procedures for radiometric calibration. All but two channels (band 2, channel 4; band 5, channel 3) behave normally. Gain changes relative to a postlaunch reference for channels within a band vary within 0.5 percent as a group. Instrument gain for channels in the cold focal plane oscillates. Noise in background and image data ranges from 0.5 to 1.7 counts. Average differences in forward and reverse image data indicate a need for separate calibration processing of forward and reverse scans. Precision is improved by increasing the pulse integration width from 31 to 41 minor frames, depending on the band.

Mississippi exploration field trials using microbial, radiometrics, free soil gas, and other techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moody, J.S.; Brown, L.R.; Thieling, S.C.

1995-12-31

The Mississippi Office of Geology has conducted field trials using the surface exploration techniques of geomicrobial, radiometrics, and free soil gas. The objective of these trials is to determine if Mississippi oil and gas fields have surface hydrocarbon expression resulting from vertical microseepage migration. Six fields have been surveyed ranging in depth from 3,330 ft to 18,500 ft. The fields differ in trapping styles and hydrocarbon type. The results so far indicate that these fields do have a surface expression and that geomicrobial analysis as well as radiometrics and free soil gas can detect hydrocarbon microseepage from pressurized reservoirs. Allmore » three exploration techniques located the reservoirs independent of depth, hydrocarbon type, or trapping style.« less

The OLI Radiometric Scale Realization Round Robin Measurement Campaign

NASA Technical Reports Server (NTRS)

Cutlip, Hansford; Cole,Jerold; Johnson, B. Carol; Maxwell, Stephen; Markham, Brian; Ong, Lawrence; Hom, Milton; Biggar, Stuart

2011-01-01

A round robin radiometric scale realization was performed at the Ball Aerospace Radiometric Calibration Laboratory in January/February 2011 in support of the Operational Land Imager (OLI) Program. Participants included Ball Aerospace, NIST, NASA Goddard Space Flight Center, and the University of Arizona. The eight day campaign included multiple observations of three integrating sphere sources by nine radiometers. The objective of the campaign was to validate the radiance calibration uncertainty ascribed to the integrating sphere used to calibrate the OLI instrument. The instrument level calibration source uncertainty was validated by quatnifying: (1) the long term stability of the NIST calibrated radiance artifact, (2) the responsivity scale of the Ball Aerospace transfer radiometer and (3) the operational characteristics of the large integrating sphere.

Radiometric characterization of Landsat Collection 1 products

USGS Publications Warehouse

Micijevic, Esad; Haque, Md. Obaidul; Mishra, Nischal

2017-01-01

Landsat data in the U.S. Geological Survey (USGS) archive are being reprocessed to generate a tiered collection of consistently geolocated and radiometrically calibrated products that are suitable for time series analyses. With the implementation of the collection management, no major updates will be made to calibration of the Landsat sensors within a collection. Only calibration parameters needed to maintain the established calibration trends without an effect on derived environmental records will be regularly updated, while all other changes will be deferred to a new collection. This first collection, Collection 1, incorporates various radiometric calibration updates to all Landsat sensors including absolute and relative gains for Landsat 8 Operational Land Imager (OLI), stray light correction for Landsat 8 Thermal Infrared Sensor (TIRS), absolute gains for Landsat 4 and 5 Thematic Mappers (TM), recalibration of Landsat 1-5 Multispectral Scanners (MSS) to ensure radiometric consistency among different formats of archived MSS data, and a transfer of Landsat 8 OLI reflectance based calibration to all previous Landsat sensors. While all OLI/TIRS, ETM+ and majority of TM data have already been reprocessed to Collection 1, a completion of MSS and remaining TM data reprocessing is expected by the end of this year. It is important to note that, although still available for download from the USGS web pages, the products generated using the Pre-Collection processing do not benefit from the latest radiometric calibration updates. In this paper, we are assessing radiometry of solar reflective bands in Landsat Collection 1 products through analysis of trends in on-board calibrator and pseudo invariant site (PICS) responses.

A definitive calibration record for the Landsat-5 thematic mapper anchored to the Landsat-7 radiometric scale

USGS Publications Warehouse

Teillet, P.M.; Helder, D.L.; Ruggles, T.A.; Landry, R.; Ahern, F.J.; Higgs, N.J.; Barsi, J.; Chander, G.; Markham, B.L.; Barker, J.L.; Thome, K.J.; Schott, J.R.; Palluconi, Frank Don

2004-01-01

A coordinated effort on the part of several agencies has led to the specification of a definitive radiometric calibration record for the Landsat-5 thematic mapper (TM) for its lifetime since launch in 1984. The time-dependent calibration record for Landsat-5 TM has been placed on the same radiometric scale as the Landsat-7 enhanced thematic mapper plus (ETM+). It has been implemented in the National Landsat Archive Production Systems (NLAPS) in use in North America. This paper documents the results of this collaborative effort and the specifications for the related calibration processing algorithms. The specifications include (i) anchoring of the Landsat-5 TM calibration record to the Landsat-7 ETM+ absolute radiometric calibration, (ii) new time-dependent calibration processing equations and procedures applicable to raw Landsat-5 TM data, and (iii) algorithms for recalibration computations applicable to some of the existing processed datasets in the North American context. The cross-calibration between Landsat-5 TM and Landsat-7 ETM+ was achieved using image pairs from the tandem-orbit configuration period that was programmed early in the Laridsat-7 mission. The time-dependent calibration for Landsat-5 TM is based on a detailed trend analysis of data from the on-board internal calibrator. The new lifetime radiometric calibration record for Landsat-5 will overcome problems with earlier product generation owing to inadequate maintenance and documentation of the calibration over time and will facilitate the quantitative examination of a continuous, near-global dataset at 30-m scale that spans almost two decades.

Radiometric characterization of Landsat Collection 1 products

NASA Astrophysics Data System (ADS)

Micijevic, Esad; Haque, Md. Obaidul; Mishra, Nischal

2017-09-01

Landsat data in the U.S. Geological Survey (USGS) archive are being reprocessed to generate a tiered collection of consistently geolocated and radiometrically calibrated products that are suitable for time series analyses. With the implementation of the collection management, no major updates will be made to calibration of the Landsat sensors within a collection. Only calibration parameters needed to maintain the established calibration trends without an effect on derived environmental records will be regularly updated, while all other changes will be deferred to a new collection. This first collection, Collection 1, incorporates various radiometric calibration updates to all Landsat sensors including absolute and relative gains for Landsat 8 Operational Land Imager (OLI), stray light correction for Landsat 8 Thermal Infrared Sensor (TIRS), absolute gains for Landsat 4 and 5 Thematic Mappers (TM), recalibration of Landsat 1-5 Multispectral Scanners (MSS) to ensure radiometric consistency among different formats of archived MSS data, and a transfer of Landsat 8 OLI reflectance based calibration to all previous Landsat sensors. While all OLI/TIRS, ETM+ and majority of TM data have already been reprocessed to Collection 1, a completion of MSS and remaining TM data reprocessing is expected by the end of this year. It is important to note that, although still available for download from the USGS web pages, the products generated using the Pre-Collection processing do not benefit from the latest radiometric calibration updates. In this paper, we are assessing radiometry of solar reflective bands in Landsat Collection 1 products through analysis of trends in on-board calibrator and pseudo invariant site (PICS) responses.

Radiometric Calibration of the NASA Advanced X-Ray Astrophysics Facility

NASA Technical Reports Server (NTRS)

Kellogg, Edwin M.

1999-01-01

We present the results of absolute calibration of the quantum efficiency of soft x-ray detectors performed at the PTB/BESSY beam lines. The accuracy goal is 1%. We discuss the implementation of that goal. These detectors were used as transfer standards to provide the radiometric calibration of the AXAF X-ray observatory, to be launched in April 1999.

Spectral and radiometric calibration of the Airborne Visible/Infrared Imaging Spectrometer

NASA Technical Reports Server (NTRS)

Vane, Gregg; Chrien, Thomas G.; Miller, Edward A.; Reimer, John H.

1987-01-01

The laboratory spectral and radiometric calibration of the AVIRIS science data collected since 1987 is described. The instrumentation and procedures used in the calibration are discussed and the accuracy achieved in the laboratory as determined by measurement and calculation is compared with the requirements. Instrument performance factors affecting radiometry are described. The paper concludes with a discussion of future plans.

The Relationship between Balancing Reactions and Reaction Lifetimes: A Consideration of the Potassium-Argon Radiometric Method for Dating Minerals

ERIC Educational Resources Information Center

Howard, William A.

2005-01-01

A detailed examination of a commonly accepted practice in geology offers an example of how to stimulate critical thinking, teaches students how to read reactions, and challenges students to formulate better experiments for determining mineral ages more accurately. A demonstration of a Potassium-Argon radiometric method for dating minerals is…

A preliminary study of a very large space radiometric antenna

NASA Technical Reports Server (NTRS)

Agrawal, P. K.

1979-01-01

An approach used to compute the size of a special radiometric reflector antenna is presented. Operating at 1 GHz, this reflector is required to produce 200 simultaneous contiguous beams, each with a 3 dB footprint of 1 km from an assumed satellite height of 650 km. The overall beam efficiency for each beam is required to be more than 90%.

Precise orbit determination of the Lunar Reconnaissance Orbiter and first gravity field results

NASA Astrophysics Data System (ADS)

Maier, Andrea; Baur, Oliver

2014-05-01

The Lunar Reconnaissance Orbiter (LRO) was launched in 2009 and is expected to orbit the Moon until the end of 2014. Among other instruments, LRO has a highly precise altimeter on board demanding an orbit accuracy of one meter in the radial component. Precise orbit determination (POD) is achieved with radiometric observations (Doppler range rates, ranges) on the one hand, and optical laser ranges on the other hand. LRO is the first satellite at a distance of approximately 360 000 to 400 000 km from the Earth that is routinely tracked with optical laser ranges. This measurement type was introduced to achieve orbits of higher precision than it would be possible with radiometric observations only. In this contribution we investigate the strength of each measurement type (radiometric range rates, radiometric ranges, optical laser ranges) based on single-technique orbit estimation. In a next step all measurement types are combined in a joined analysis. In addition to POD results, preliminary gravity field coefficients are presented being a subsequent product of the orbit determination process. POD and gravity field estimation was accomplished with the NASA/GSFC software packages GEODYN and SOLVE.

Radiometric Calibration of a Dual-Wavelength, Full-Waveform Terrestrial Lidar.

PubMed

Li, Zhan; Jupp, David L B; Strahler, Alan H; Schaaf, Crystal B; Howe, Glenn; Hewawasam, Kuravi; Douglas, Ewan S; Chakrabarti, Supriya; Cook, Timothy A; Paynter, Ian; Saenz, Edward J; Schaefer, Michael

2016-03-02

Radiometric calibration of the Dual-Wavelength Echidna(®) Lidar (DWEL), a full-waveform terrestrial laser scanner with two simultaneously-pulsing infrared lasers at 1064 nm and 1548 nm, provides accurate dual-wavelength apparent reflectance (ρ(app)), a physically-defined value that is related to the radiative and structural characteristics of scanned targets and independent of range and instrument optics and electronics. The errors of ρ(app) are 8.1% for 1064 nm and 6.4% for 1548 nm. A sensitivity analysis shows that ρ(app) error is dominated by range errors at near ranges, but by lidar intensity errors at far ranges. Our semi-empirical model for radiometric calibration combines a generalized logistic function to explicitly model telescopic effects due to defocusing of return signals at near range with a negative exponential function to model the fall-off of return intensity with range. Accurate values of ρ(app) from the radiometric calibration improve the quantification of vegetation structure, facilitate the comparison and coupling of lidar datasets from different instruments, campaigns or wavelengths and advance the utilization of bi- and multi-spectral information added to 3D scans by novel spectral lidars.

Method of radiometric quality assessment of NIR images acquired with a custom sensor mounted on an unmanned aerial vehicle

NASA Astrophysics Data System (ADS)

Wierzbicki, Damian; Fryskowska, Anna; Kedzierski, Michal; Wojtkowska, Michalina; Delis, Paulina

2018-01-01

Unmanned aerial vehicles are suited to various photogrammetry and remote sensing missions. Such platforms are equipped with various optoelectronic sensors imaging in the visible and infrared spectral ranges and also thermal sensors. Nowadays, near-infrared (NIR) images acquired from low altitudes are often used for producing orthophoto maps for precision agriculture among other things. One major problem results from the application of low-cost custom and compact NIR cameras with wide-angle lenses introducing vignetting. In numerous cases, such cameras acquire low radiometric quality images depending on the lighting conditions. The paper presents a method of radiometric quality assessment of low-altitude NIR imagery data from a custom sensor. The method utilizes statistical analysis of NIR images. The data used for the analyses were acquired from various altitudes in various weather and lighting conditions. An objective NIR imagery quality index was determined as a result of the research. The results obtained using this index enabled the classification of images into three categories: good, medium, and low radiometric quality. The classification makes it possible to determine the a priori error of the acquired images and assess whether a rerun of the photogrammetric flight is necessary.

Application of radiometric force to microactuation and energy transformation

NASA Astrophysics Data System (ADS)

Selden, Nathaniel; Gimelshein, Natalia; Gimelshein, Sergey; Ketsdever, Andrew

2012-11-01

The force that acts on a thin vane immersed in rarefied gas when a temperature gradient is imposed along or across the vane has historically been known as the Radiometric force. First observed by Fresnel in 1825, the radiometric force has regained its former popularity in recent decades due to the advent of micro-machines, where a transitional flow regime can occur at atmospheric pressures. Whether used for its force potential or simply viewed as a nuisance, this force cannot be ignored in micro-devices where thermal gradients exist. Potential applications of radiometric force now span from atomic force microscopy to astrophysics to high altitude flight. This paper describes an application of these forces to a conceptual micro-scale energy harvester, where two possible geometries of operation are described. It is shown that one configuration is significantly simpler to fabricate while the other geometry is more efficient at producing larger forces. The effect of pressure, feature separation, and feature-to-ring gap are analyzed. For consistency and the accurate treatment of the relevant flow conditions, an implementation of the SMOKE code that solves the ES BGK equation was used in all computations.

Characterizing the natural radiation levels throughout the main geological units of Sabkhat al Jabboul area, northern Syria.

PubMed

Al-Hilal, Mohamed; Aissa, Mosa

2015-02-01

The concentrations of equivalent eU, eTh, and K% were determined together with soil gas radon values and carborne gamma-ray survey in order to define the natural radioactivity levels throughout main geological units of Sabkhat al Jabboul region. Forty five soil and rock samples were collected from various lithofacies in each geological unit, and analyzed by γ-ray spectrometric technique for determining the concentration values of major radioelements. Such radiometric data could be used to differentiate between various lithologies of the investigated rocks. Although no distinct radioactive anomalies were found in the area, the radiometric profiles showed some minor variations with slightly higher values than the normal level. Despite the low radioactivity and the lack of rocks diversity in the surveyed area, it was possible to classify some certain rock types based on their radiometric response. The relationships between eU, eTh and their ratios were discussed for the Quaternary, Neogene and Paleogene formations, in order to evaluate the degree of uranium distribution and remobilization. The overall results of this radiometric survey were generally low, and lying within the range of the normal background levels in Syrian. Copyright © 2014 Elsevier Ltd. All rights reserved.

Radiometric stability of the Multi-angle Imaging SpectroRadiometer (MISR) following 15 years on-orbit

NASA Astrophysics Data System (ADS)

Bruegge, Carol J.; Val, Sebastian; Diner, David J.; Jovanovic, Veljko; Gray, Ellyn; Di Girolamo, Larry; Zhao, Guangyu

2014-09-01

The Multi-angle Imaging SpectroRadiometer (MISR) has successfully operated on the EOS/ Terra spacecraft since 1999. It consists of nine cameras pointing from nadir to 70.5° view angle with four spectral channels per camera. Specifications call for a radiometric uncertainty of 3% absolute and 1% relative to the other cameras. To accomplish this, MISR utilizes an on-board calibrator (OBC) to measure camera response changes. Once every two months the two Spectralon panels are deployed to direct solar-light into the cameras. Six photodiode sets measure the illumination level that are compared to MISR raw digital numbers, thus determining the radiometric gain coefficients used in Level 1 data processing. Although panel stability is not required, there has been little detectable change in panel reflectance, attributed to careful preflight handling techniques. The cameras themselves have degraded in radiometric response by 10% since launch, but calibration updates using the detector-based scheme has compensated for these drifts and allowed the radiance products to meet accuracy requirements. Validation using Sahara desert observations show that there has been a drift of ~1% in the reported nadir-view radiance over a decade, common to all spectral bands.

Radiometric Correction of Multitemporal Hyperspectral Uas Image Mosaics of Seedling Stands

NASA Astrophysics Data System (ADS)

Markelin, L.; Honkavaara, E.; Näsi, R.; Viljanen, N.; Rosnell, T.; Hakala, T.; Vastaranta, M.; Koivisto, T.; Holopainen, M.

2017-10-01

Novel miniaturized multi- and hyperspectral imaging sensors on board of unmanned aerial vehicles have recently shown great potential in various environmental monitoring and measuring tasks such as precision agriculture and forest management. These systems can be used to collect dense 3D point clouds and spectral information over small areas such as single forest stands or sample plots. Accurate radiometric processing and atmospheric correction is required when data sets from different dates and sensors, collected in varying illumination conditions, are combined. Performance of novel radiometric block adjustment method, developed at Finnish Geospatial Research Institute, is evaluated with multitemporal hyperspectral data set of seedling stands collected during spring and summer 2016. Illumination conditions during campaigns varied from bright to overcast. We use two different methods to produce homogenous image mosaics and hyperspectral point clouds: image-wise relative correction and image-wise relative correction with BRDF. Radiometric datasets are converted to reflectance using reference panels and changes in reflectance spectra is analysed. Tested methods improved image mosaic homogeneity by 5 % to 25 %. Results show that the evaluated method can produce consistent reflectance mosaics and reflectance spectra shape between different areas and dates.

Radiometric Calibration of a Dual-Wavelength, Full-Waveform Terrestrial Lidar

PubMed Central

Li, Zhan; Jupp, David L. B.; Strahler, Alan H.; Schaaf, Crystal B.; Howe, Glenn; Hewawasam, Kuravi; Douglas, Ewan S.; Chakrabarti, Supriya; Cook, Timothy A.; Paynter, Ian; Saenz, Edward J.; Schaefer, Michael

2016-01-01

Radiometric calibration of the Dual-Wavelength Echidna® Lidar (DWEL), a full-waveform terrestrial laser scanner with two simultaneously-pulsing infrared lasers at 1064 nm and 1548 nm, provides accurate dual-wavelength apparent reflectance (ρapp), a physically-defined value that is related to the radiative and structural characteristics of scanned targets and independent of range and instrument optics and electronics. The errors of ρapp are 8.1% for 1064 nm and 6.4% for 1548 nm. A sensitivity analysis shows that ρapp error is dominated by range errors at near ranges, but by lidar intensity errors at far ranges. Our semi-empirical model for radiometric calibration combines a generalized logistic function to explicitly model telescopic effects due to defocusing of return signals at near range with a negative exponential function to model the fall-off of return intensity with range. Accurate values of ρapp from the radiometric calibration improve the quantification of vegetation structure, facilitate the comparison and coupling of lidar datasets from different instruments, campaigns or wavelengths and advance the utilization of bi- and multi-spectral information added to 3D scans by novel spectral lidars. PMID:26950126

Temporal dynamics of sand dune bidirectional reflectance characteristics for absolute radiometric calibration of optical remote sensing data

NASA Astrophysics Data System (ADS)

Coburn, Craig A.; Logie, Gordon S. J.

2018-01-01

Attempts to use pseudoinvariant calibration sites (PICS) for establishing absolute radiometric calibration of Earth observation (EO) satellites requires high-quality information about the nature of the bidirectional reflectance distribution function (BRDF) of the surfaces used for these calibrations. Past studies have shown that the PICS method is useful for evaluating the trend of sensors over time or for the intercalibration of sensors. The PICS method was not considered until recently for deriving absolute radiometric calibration. This paper presents BRDF data collected by a high-performance portable goniometer system to develop a temporal BRDF model for the Algodones Dunes in California. By sampling the BRDF of the sand surface at similar solar zenith angles to those normally encountered by EO satellites, additional information on the changing nature of the surface can improve models used to provide absolute radiometric correction. The results demonstrated that the BRDF of a reasonably simple sand surface was complex with changes in anisotropy taking place in response to changing solar zenith angles. For the majority of observation and illumination angles, the spectral reflectance anisotropy observed varied between 1% and 5% in patterns that repeat around solar noon.

Non-invasive hyperthermia apparatus including coaxial applicator having a non-invasive radiometric receiving antenna incorporated therein and method of use thereof

DOEpatents

Ross, Michael P.

1996-01-01

A coaxial hyperthermia applicator for applying non-invasively electromagnetic energy to a body against which it is placed. The coaxial applicator antenna has formed integrally within it a non-invasive radiometric antenna for receiving thermoelectromagnetic emissions. The coaxial-configured applicator produces a bell-shaped radiation pattern symmetric about the axis of symmetry of the coaxial applicator. Integrating the radiometric antenna within the coaxial applicator produces a single device that performs dual functions. The first function is to transmit non-invasively energy for heating a subcutaneous tumor. The second function is to receive non-invasively thermal electromagnetic radiation from the tumor by which temperature is sensed and fed back to control the output of the coaxial applicator.

Non-invasive hyperthermia apparatus including coaxial applicator having a non-invasive radiometric receiving antenna incorporated therein and method of use thereof

DOEpatents

Ross, M.P.

1996-08-27

A coaxial hyperthermia applicator is disclosed for applying non-invasively electromagnetic energy to a body against which it is placed. The coaxial applicator antenna has formed integrally within it a non-invasive radiometric antenna for receiving thermoelectromagnetic emissions. The coaxial-configured applicator produces a bell-shaped radiation pattern symmetric about the axis of symmetry of the coaxial applicator. Integrating the radiometric antenna within the coaxial applicator produces a single device that performs dual functions. The first function is to transmit non-invasively energy for heating a subcutaneous tumor. The second function is to receive non-invasively thermal electromagnetic radiation from the tumor by which temperature is sensed and fed back to control the output of the coaxial applicator. 11 figs.

Radiometric and Spatial Characterization of High-Spatial Resolution Sensors

NASA Technical Reports Server (NTRS)

Thome, Kurtis; Zanoni, Vicki (Technical Monitor)

2002-01-01

The development and improvement of commercial hyperspatial sensors in recent years has increased the breadth of information that can be retrieved from spaceborne and airborne imagery. NASA, through it's Scientific Data Purchases, has successfully provided such data sets to its user community. A key element to the usefulness of these data are an understanding of the radiometric and spatial response quality of the imagery. This proposal seeks funding to examine the absolute radiometric calibration of the Ikonos sensor operated by Space Imaging and the recently-launched Quickbird sensor from DigitalGlobe. In addition, we propose to evaluate the spatial response of the two sensors. The proposed methods rely on well-understood, ground-based targets that have been used by the University of Arizona for more than a decade.

THEMIS Images as Art #59

NASA Technical Reports Server (NTRS)

2005-01-01

Welcome to another brief interval of THEMIS Images as Art. For two weeks, we will be showcasing images for their aesthetic value rather than their science content. Portions of these images resemble things in our everyday lives, from animals to letters of the alphabet. We hope you enjoy our fanciful look at Mars!

Perhaps a louse, or maybe some sort of unicellular organism?

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

Development of a novel cell sorting method that samples population diversity in flow cytometry.

PubMed

Osborne, Geoffrey W; Andersen, Stacey B; Battye, Francis L

2015-11-01

Flow cytometry based electrostatic cell sorting is an important tool in the separation of cell populations. Existing instruments can sort single cells into multi-well collection plates, and keep track of cell of origin and sorted well location. However currently single sorted cell results reflect the population distribution and fail to capture the population diversity. Software was designed that implements a novel sorting approach, "Slice and Dice Sorting," that links a graphical representation of a multi-well plate to logic that ensures that single cells are sampled and sorted from all areas defined by the sort region/s. Therefore the diversity of the total population is captured, and the more frequently occurring or rarer cell types are all sampled. The sorting approach was tested computationally, and using functional cell based assays. Computationally we demonstrate that conventional single cell sorting can sample as little as 50% of the population diversity dependant on the population distribution, and that Slice and Dice sorting samples much more of the variety present within a cell population. We then show by sorting single cells into wells using the Slice and Dice sorting method that there are cells sorted using this method that would be either rarely sorted, or not sorted at all using conventional single cell sorting approaches. The present study demonstrates a novel single cell sorting method that samples much more of the population diversity than current methods. It has implications in clonal selection, stem cell sorting, single cell sequencing and any areas where population heterogeneity is of importance. © 2015 International Society for Advancement of Cytometry.

LANDSAT-4 multispectral scanner (MSS) subsystem radiometric characterization

NASA Technical Reports Server (NTRS)

Alford, W. (Editor); Barker, J. (Editor); Clark, B. P.; Dasgupta, R.

1983-01-01

The multispectral band scanner (mass) and its spectral characteristics are described and methods are given for relating video digital levels on computer compatible tapes to radiance into the sensor. Topics covered include prelaunch calibration procedures and postlaunch radiometric processng. Examples of current data resident on the MSS image processing system are included. The MSS on LANDSAT 4 is compared with the scanners on earlier LANDSAT satellites.

Initial Radiometric Calibration of the AWiFS using Vicarious Calibration Techniques

NASA Technical Reports Server (NTRS)

Pagnutti, Mary; Thome, Kurtis; Aaron, David; Leigh, Larry

2006-01-01

NASA SSC maintains four ASD FieldSpec FR spectroradiometers: 1) Laboratory transfer radiometers; 2) Ground surface reflectance for V&V field collection activities. Radiometric Calibration consists of a NIST-calibrated integrating sphere which serves as a source with known spectral radiance. Spectral Calibration consists of a laser and pen lamp illumination of integrating sphere. Environmental Testing includes temperature stability tests performed in environmental chamber.

VIIRS ZEMAX and FORTRAN Polarization Models

NASA Technical Reports Server (NTRS)

Waluschka, Eugene; Meister, Gerhard; Voss, Kenneth; Moyer, David

2007-01-01

The Visible/Infrared Imager/Radiometer Suite (VIIRS) collects visible/infrared imagery and radiometric data. The radiometric requirements are such that the instrument's polarization sensitivity must be very well understood. This paper presents the ZEMAX and FORTRAN polarization ray trace models of the instrument's visible light path. This will include the measured optical surface reflectance data, the bandpass shapes and a comparison of the results of the two models.

LANDSAT 4 band 6 data evaluation

NASA Technical Reports Server (NTRS)

1984-01-01

The objectives of this investigation are to evaluate and monitor the radiometric integrity of the LANDSAT-D Thematic Mapper (TM) thermal infrared channel (Band 6) data to develop improved radiometric preprocessing calibration techniques for removal of atmospheric effects. Efforts this period have concentrated on underflight data collection. Two successful flights were made on September 18 and October 6. The radiosonde data for these flights have been obtained.

Radiometric Measurement Comparisons Using Transfer Radiometers in Support of the Calibration of NASA's Earth Observing System (EOS) Sensors

NASA Technical Reports Server (NTRS)

Butler, James J.; Johnson, B. Carol; Brown, Steven W.; Yoon, Howard W.; Barnes, Robert A.; Markham, Brian L.; Biggar, Stuart F.; Zalewski, Edward F.; Spyak, Paul R.; Cooper, John W.;

Development of radiometric assays for quantification of enzyme activities of the key enzymes of thyroid hormones metabolism.

PubMed

Pavelka, S

2014-01-01

We newly elaborated and adapted several radiometric enzyme assays for the determination of activities of the key enzymes engaged in the biosynthesis (thyroid peroxidase, TPO) and metabolic transformations (conjugating enzymes and iodothyronine deiodinases, IDs) of thyroid hormones (THs) in the thyroid gland and in peripheral tissues, especially in white adipose tissue (WAT). We also elaborated novel, reliable radiometric methods for extremely sensitive determination of enzyme activities of IDs of types 1, 2 and 3 in microsomal fractions of different rat and human tissues, as well as in homogenates of cultured mammalian cells. The use of optimized TLC separation of radioactive products from the unconsumed substrates and film-less autoradiography of radiochromatograms, taking advantage of storage phosphor screens, enabled us to determine IDs enzyme activities as low as 10(-18) katals. In studies of the interaction of fluoxetine (Fluox) with the metabolism of THs, we applied adapted radiometric enzyme assays for iodothyronine sulfotransferases (ST) and uridine 5'-diphospho-glucuronyltransferase (UDP-GT). Fluox is the most frequently used representative of a new group of non-tricyclic antidepressant drugs--selective serotonin re-uptake inhibitors. We used the elaborated assays for quantification the effects of Fluox and for the assessment of the degree of potential induction of rat liver ST and/or UDP-GT enzyme activities by Fluox alone or in combination with T(3). Furthermore, we studied possible changes in IDs activities in murine adipose tissue under the conditions that promoted either tissue hypertrophy (obesogenic treatment) or involution (caloric restriction), and in response to leptin, using our newly developed radiometric enzyme assays for IDs. Our results suggest that deiodinase D1 has a functional role in WAT, with D1 possibly being involved in the control of adipose tissue metabolism and/or accumulation of the tissue. Significant positive correlation between specific enzyme activity of D1 in WAT and plasma leptin levels was found. The newly developed and adapted radiometric enzyme assays proved to be very useful tools for studies of factors modulating THs metabolism, not only in model animals but also in clinical studies of human obesity.

Ground-based radiometric calibration of the Landsat 8 Operational Land Imager (OLI) using in situ techniques

NASA Astrophysics Data System (ADS)

Czapla-Myers, J.

2013-12-01

Landsat 8 was successfully launched from Vandenberg Air Force Base in California on 11 February 2013, and was placed into the orbit previously occupied by Landsat 5. Landsat 8 is the latest platform in the 40-year history of the Landsat series of satellites, and it contains two instruments that operate in the solar-reflective and the thermal infrared regimes. The Operational Land Imager (OLI) is a pushbroom sensor that contains eight multispectral bands ranging from 400-2300 nm, and one panchromatic band. The spatial resolution of the multispectral bands is 30 m, which is similar to previous Landsat sensors, and the panchromatic band has a 15-m spatial resolution, which is also similar to previous Landsat sensors. The 12-bit radiometric resolution of OLI improves upon the 8-bit resolution of the Enhanced Thematic Mapper Plus (ETM+) onboard Landsat 7. An important requirement for the Landsat program is the long-term radiometric continuity of its sensors. Ground-based vicarious techniques have been used for over 20 years to determine the absolute radiometric calibration of sensors that encompass a wide variety of spectral and spatial characteristics. This work presents the early radiometric calibration results of Landsat 8 OLI that were obtained using the traditional reflectance-based approach. University of Arizona personnel used five sites in Arizona, California, and Nevada to collect ground-based data. In addition, a unique set of in situ data were collected in March 2013, when Landsat 7 and Landsat 8 were observing the same site within minutes of each other. The tandem overfly schedule occurred while Landsat 8 was shifting to the WRS-2 orbital grid, and lasted only a few days. The ground-based data also include results obtained using the University of Arizona's Radiometric Calibration Test Site (RadCaTS), which is an automated suite of instruments located at Railroad Valley, Nevada. The results presented in this work include a comparison to the L1T at-sensor spectral radiance and the top-of-atmosphere reflectance, both of which are standard products available from the US Geological Survey.

A task analysis of the shift from teacher instructions to self-instructions in performing an in-common task.

PubMed

Grote, I; Rosales, J; Baer, D M

1996-11-01

Three preschool children repeatedly did four kinds of sorts with a deck of stimulus cards: a difficult, untaught target sort and three other sorts considered analytic of self-instructing the target performance. The untaught target sort was to find in a deck of cards those matching what two sample cards had in common. Most preschool children must be taught to mediate this problem. The three other kinds of sorts taught skills involved in the target performance or its mediation. As correct self-instructive talk emerged in the target sorts, it was confirmed. The untaught target sorts were interspersed infrequently among the three alternating directly taught skill sorts, to see if accurate target sorts, and accurate self-instructive talk about the target sorts, would emerge as the three skill sorts were mastered. As all the sorts progressed, increasing accuracy was seen first in the skill sorts and then in the untaught target sorts. All three subjects showed subsequent generalization to new target sorts involving other stimulus sets. Correct spontaneous self-instructions about the target sorts increased from near zero at the beginning of the experiment to consistency at its end. Thus the three skill sorts appeared sufficient for the emergence of a self-instructed solution to the previously insoluble target performance.

Parallel sort with a ranged, partitioned key-value store in a high perfomance computing environment

DOEpatents

Bent, John M.; Faibish, Sorin; Grider, Gary; Torres, Aaron; Poole, Stephen W.

2016-01-26

Improved sorting techniques are provided that perform a parallel sort using a ranged, partitioned key-value store in a high performance computing (HPC) environment. A plurality of input data files comprising unsorted key-value data in a partitioned key-value store are sorted. The partitioned key-value store comprises a range server for each of a plurality of ranges. Each input data file has an associated reader thread. Each reader thread reads the unsorted key-value data in the corresponding input data file and performs a local sort of the unsorted key-value data to generate sorted key-value data. A plurality of sorted, ranged subsets of each of the sorted key-value data are generated based on the plurality of ranges. Each sorted, ranged subset corresponds to a given one of the ranges and is provided to one of the range servers corresponding to the range of the sorted, ranged subset. Each range server sorts the received sorted, ranged subsets and provides a sorted range. A plurality of the sorted ranges are concatenated to obtain a globally sorted result.

High speed radiometric measurements of IED detonation fireballs

NASA Astrophysics Data System (ADS)

Spidell, Matthew T.; Gordon, J. Motos; Pitz, Jeremey; Gross, Kevin C.; Perram, Glen P.

2010-04-01

Continuum emission is predominant in fireball spectral phenomena and in some demonstrated cases, fine detail in the temporal evolution of infrared spectral emissions can be used to estimate size and chemical composition of the device. Recent work indicates that a few narrow radiometric bands may reveal forensic information needed for the explosive discrimination and classification problem, representing an essential step in moving from "laboratory" measurements to a rugged, fieldable system. To explore phenomena not observable in previous experiments, a high speed (10μs resolution) radiometer with four channels spanning the infrared spectrum observed the detonation of nine home made explosive (HME) devices in the < 100lb class. Radiometric measurements indicate that the detonation fireball is well approximated as a single temperature blackbody at early time (0 < t <~ 3ms). The effective radius obtained from absolute intensity indicates fireball growth at supersonic velocity during this time. Peak fireball temperatures during this initial detonation range between 3000.3500K. The initial temperature decay with time (t <~ 10ms) can be described by a simple phenomenological model based on radiative cooling. After this rapid decay, temperature exhibits a small, steady increase with time (10 <~ t <~ 50ms) and peaking somewhere between 1000.1500K-likely the result of post-detonation combustion-before subsequent cooling back to ambient conditions . Radius derived from radiometric measurements can be described well (R2 > 0.98) using blast model functional forms, suggesting that energy release could be estimated from single-pixel radiometric detectors. Comparison of radiometer-derived fireball size with FLIR infrared imagery indicate the Planckian intensity size estimates are about a factor of two smaller than the physical extent of the fireball.

Uncertainty Evaluations of the CRCS In-orbit Field Radiometric Calibration Methods for Thermal Infrared Channels of FENGYUN Meteorological Satellites

NASA Astrophysics Data System (ADS)

Zhang, Y.; Rong, Z.; Min, M.; Hao, X.; Yang, H.

2017-12-01

Meteorological satellites have become an irreplaceable weather and ocean-observing tool in China. These satellites are used to monitor natural disasters and improve the efficiency of many sectors of Chinese national economy. It is impossible to ignore the space-derived data in the fields of meteorology, hydrology, and agriculture, as well as disaster monitoring in China, a large agricultural country. For this reason, China is making a sustained effort to build and enhance its meteorological observing system and application system. The first Chinese polar-orbiting weather satellite was launched in 1988. Since then China has launched 14 meteorological satellites, 7 of which are sun synchronous and 7 of which are geostationary satellites; China will continue its two types of meteorological satellite programs. In order to achieve the in-orbit absolute radiometric calibration of the operational meteorological satellites' thermal infrared channels, China radiometric calibration sites (CRCS) established a set of in-orbit field absolute radiometric calibration methods (FCM) for thermal infrared channels (TIR) and the uncertainty of this method was evaluated and analyzed based on TERRA/AQUA MODIS observations. Comparisons between the MODIS at pupil brightness temperatures (BTs) and the simulated BTs at the top of atmosphere using radiative transfer model (RTM) based on field measurements showed that the accuracy of the current in-orbit field absolute radiometric calibration methods was better than 1.00K (@300K, K=1) in thermal infrared channels. Therefore, the current CRCS field calibration method for TIR channels applied to Chinese metrological satellites was with favorable calibration accuracy: for 10.5-11.5µm channel was better than 0.75K (@300K, K=1) and for 11.5-12.5µm channel was better than 0.85K (@300K, K=1).

Airborne gamma-ray spectrometer and magnetometer survey, Durango A, B, C, and D, Colorado. Volume I. Detail area. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1983-01-01

An airborne combined radiometric and magnetic survey was performed for the Department of Energy (DOE) over the Durango A, Durango B, Durango C, and Durango D Detail Areas of southwestern Colorado. The Durango A Detail Area is within the coverage of the Needle Mountains and Silverton 15' map sheets, and the Pole Creek Mountain, Rio Grande Pyramid, Emerald Lake, Granite Peak, Vallecito Reservoir, and Lemon Reservoir 7.5' map sheets of the National Topographic Map Series (NTMS). The Durango B Detail Area is within the coverage of the Silverton 15' map sheet and the Wetterhorn Peak, Uncompahgre Peak, Lake City, Redcloudmore » Peak, Lake San Cristobal, Pole Creek Mountain, and Finger Mesa 7.5' map sheets of the NTMS. The Durango C Detail Area is within the coverage of the Platoro and Wolf Creek Pass 15' map sheets of the NTMS. The Durango D Detail Area is within the coverage of the Granite Lake, Cimarrona Peak, Bear Mountain, and Oakbrush Ridge 7.5' map sheets of the NTMS. Radiometric data were corrected for live time, aircraft and equipment background, cosmic background, atmospheric radon, Compton scatter, and altitude dependence. The corrected data were statistically evaluated, gridded, and contoured to produce maps of the radiometric variables, uranium, potassium, and thorium; their ratios; and the residual magnetic field. These maps have been analyzed in order to produce a multi-variant analysis contour map based on the radiometric response of the individual geological units. A geochemical analysis has been performed, using the radiometric and magnetic contour maps, the multi-variant analysis map, and factor analysis techniques, to produce a geochemical analysis map for the area.« less

Classification of high-resolution multi-swath hyperspectral data using Landsat 8 surface reflectance data as a calibration target and a novel histogram based unsupervised classification technique to determine natural classes from biophysically relevant fit parameters

NASA Astrophysics Data System (ADS)

McCann, C.; Repasky, K. S.; Morin, M.; Lawrence, R. L.; Powell, S. L.

2016-12-01

Compact, cost-effective, flight-based hyperspectral imaging systems can provide scientifically relevant data over large areas for a variety of applications such as ecosystem studies, precision agriculture, and land management. To fully realize this capability, unsupervised classification techniques based on radiometrically-calibrated data that cluster based on biophysical similarity rather than simply spectral similarity are needed. An automated technique to produce high-resolution, large-area, radiometrically-calibrated hyperspectral data sets based on the Landsat surface reflectance data product as a calibration target was developed and applied to three subsequent years of data covering approximately 1850 hectares. The radiometrically-calibrated data allows inter-comparison of the temporal series. Advantages of the radiometric calibration technique include the need for minimal site access, no ancillary instrumentation, and automated processing. Fitting the reflectance spectra of each pixel using a set of biophysically relevant basis functions reduces the data from 80 spectral bands to 9 parameters providing noise reduction and data compression. Examination of histograms of these parameters allows for determination of natural splitting into biophysical similar clusters. This method creates clusters that are similar in terms of biophysical parameters, not simply spectral proximity. Furthermore, this method can be applied to other data sets, such as urban scenes, by developing other physically meaningful basis functions. The ability to use hyperspectral imaging for a variety of important applications requires the development of data processing techniques that can be automated. The radiometric-calibration combined with the histogram based unsupervised classification technique presented here provide one potential avenue for managing big-data associated with hyperspectral imaging.

BOREAS TE-18, 60-m, Radiometrically Rectified Landsat TM Imagery

NASA Technical Reports Server (NTRS)

Hall, Forrest G. (Editor); Knapp, David

2000-01-01

The BOREAS TE-18 team used a radiometric rectification process to produce standardized DN values for a series of Landsat TM images of the BOREAS SSA and NSA in order to compare images that were collected under different atmospheric conditions. The images for each study area were referenced to an image that had very clear atmospheric qualities. The reference image for the SSA was collected on 02-Sep-1994, while the reference image for the NSA was collected on 2 1 Jun-1995. The 23 rectified images cover the period of 07-Jul-1985 to 18-Sep-1994 in the SSA and 22-Jun-1984 to 09-Jun-1994 in the NSA. Each of the reference scenes had coincident atmospheric optical thickness measurements made by RSS-11. The radiometric rectification process is described in more detail by Hall et al. (1991). The original Landsat TM data were received from CCRS for use in the BOREAS project. Due to the nature of the radiometric rectification process and copyright issues, the full-resolution (30-m) images may not be publicly distributed. However, this spatially degraded 60-m resolution version of the images may be openly distributed and is available on the BOREAS CD-ROM series. After the radiometric rectification processing, the original data were degraded to a 60-m pixel size from the original 30-m pixel size by averaging the data over a 2- by 2-pixel window. The data are stored in binary image-format files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Activity Archive Center (DAAC).

Validation of EO-1 Hyperion and Advanced Land Imager Using the Radiometric Calibration Test Site at Railroad Valley, Nevada

NASA Technical Reports Server (NTRS)

Czapla-Myers, Jeffrey; Ong, Lawrence; Thome, Kurtis; McCorkel, Joel

2015-01-01

The Earth-Observing One (EO-1) satellite was launched in 2000. Radiometric calibration of Hyperion and the Advanced Land Imager (ALI) has been performed throughout the mission lifetime using various techniques that include ground-based vicarious calibration, pseudo-invariant calibration sites, and also the moon. The EO-1 mission is nearing its useful lifetime, and this work seeks to validate the radiometric calibration of Hyperion and ALI from 2013 until the satellite is decommissioned. Hyperion and ALI have been routinely collecting data at the automated Radiometric Calibration Test Site [RadCaTS/Railroad Valley (RRV)] since launch. In support of this study, the frequency of the acquisitions at RadCaTS has been significantly increased since 2013, which provides an opportunity to analyze the radiometric stability and accuracy during the final stages of the EO-1 mission. The analysis of Hyperion and ALI is performed using a suite of ground instrumentation that measures the atmosphere and surface throughout the day. The final product is an estimate of the top-of-atmosphere (TOA) spectral radiance, which is compared to Hyperion and ALI radiances. The results show that Hyperion agrees with the RadCaTS predictions to within 5% in the visible and near-infrared (VNIR) and to within 10% in the shortwave infrared (SWIR). The 2013-2014 ALI results show agreement to within 6% in the VNIR and 7.5% in the SWIR bands. A cross comparison between ALI and the Operational Land Imager (OLI) using RadCaTS as a transfer source shows agreement of 3%-6% during the period of 2013-2014.

Sentinel-2 radiometric image quality commissioning: first results

NASA Astrophysics Data System (ADS)

Lachérade, S.; Lonjou, V.; Farges, M.; Gamet, P.; Marcq, S.; Raynaud, J.-L.; Trémas, T.

2015-10-01

In partnership with the European Commission and in the frame of the Copernicus program, the European Space Agency (ESA) is developing the Sentinel-2 optical imaging mission devoted to the operational monitoring of land and coastal areas. The Sentinel-2 mission is based on a satellites constellation deployed in polar sun-synchronous orbit. Sentinel-2 offers a unique combination of global coverage with a wide field of view (290km), a high revisit (5 days with two satellites), a high spatial resolution (10m, 20m and 60m) and multi-spectral imagery (13 spectral bands in visible and shortwave infrared domains). The first satellite, Sentinel-2A, has been launched in June 2015. The Sentinel-2A Commissioning Phase starts immediately after the Launch and Early Orbit Phase and continues until the In-Orbit Commissioning Review which is planned three months after the launch. The Centre National d'Etudes Spatiales (CNES) supports ESA/ESTEC to insure the Calibration/Validation commissioning phase during the first three months in flight. This paper provides first an overview of the Sentinel-2 system and a description of the products delivered by the ground segment associated to the main radiometric specifications to achieve. Then the paper focuses on the preliminary radiometric results obtained during the in-flight commissioning phase. The radiometric methods and calibration sites used in the CNES image quality center to reach the specifications of the sensor are described. A status of the Sentinel-2A radiometric performances at the end of the first three months after the launch is presented. We will particularly address in this paper the results in term of absolute calibration, pixel to pixel relative sensitivity and MTF estimation.

Geometric Calibration and Radiometric Correction of the Maia Multispectral Camera

NASA Astrophysics Data System (ADS)

Nocerino, E.; Dubbini, M.; Menna, F.; Remondino, F.; Gattelli, M.; Covi, D.

2017-10-01

Multispectral imaging is a widely used remote sensing technique, whose applications range from agriculture to environmental monitoring, from food quality check to cultural heritage diagnostic. A variety of multispectral imaging sensors are available on the market, many of them designed to be mounted on different platform, especially small drones. This work focuses on the geometric and radiometric characterization of a brand-new, lightweight, low-cost multispectral camera, called MAIA. The MAIA camera is equipped with nine sensors, allowing for the acquisition of images in the visible and near infrared parts of the electromagnetic spectrum. Two versions are available, characterised by different set of band-pass filters, inspired by the sensors mounted on the WorlView-2 and Sentinel2 satellites, respectively. The camera details and the developed procedures for the geometric calibrations and radiometric correction are presented in the paper.

Radiometrically accurate scene-based nonuniformity correction for array sensors.

PubMed

Ratliff, Bradley M; Hayat, Majeed M; Tyo, J Scott

2003-10-01

A novel radiometrically accurate scene-based nonuniformity correction (NUC) algorithm is described. The technique combines absolute calibration with a recently reported algebraic scene-based NUC algorithm. The technique is based on the following principle: First, detectors that are along the perimeter of the focal-plane array are absolutely calibrated; then the calibration is transported to the remaining uncalibrated interior detectors through the application of the algebraic scene-based algorithm, which utilizes pairs of image frames exhibiting arbitrary global motion. The key advantage of this technique is that it can obtain radiometric accuracy during NUC without disrupting camera operation. Accurate estimates of the bias nonuniformity can be achieved with relatively few frames, which can be fewer than ten frame pairs. Advantages of this technique are discussed, and a thorough performance analysis is presented with use of simulated and real infrared imagery.

The effects of vegetation cover on the radar and radiometric sensitivity to soil moisture

NASA Technical Reports Server (NTRS)

Ulaby, F. T.; Dobson, M. C.; Brunfeldt, D. R.; Razani, M.

1982-01-01

The measured effects of vegetation canopies on radar and radiometric sensitivity to soil moisture are compared to emission and scattering models. The models are found to predict accurately the measured emission and backscattering for various crop canopies at frequencies between 1.4 and 5.0 GHz, especially at theta equal to or less than 30 deg. Vegetation loss factors, L(theta), increase with frequency and are found to be dependent upon canopy type and water content. In addition, the radiometric power absorption coefficient of a mature corn canopy is 1.75 times that calculated for the radar. Comparison of an L-band radiometer with a C-band radar shows the two systems to be complementary in terms of accurate soil moisture sensing over the extreme range of naturally occurring soil moisture conditions.

Experimental tests and radiometric calculations for the feasibility of fluorescence LIDAR-based discrimination of oil spills from UAV

NASA Astrophysics Data System (ADS)

Raimondi, Valentina; Palombi, Lorenzo; Lognoli, David; Masini, Andrea; Simeone, Emilio

2017-09-01

This paper presents experimental tests and radiometric calculations for the feasibility of an ultra-compact fluorescence LIDAR from an Unmanned Air Vehicle (UAV) for the characterisation of oil spills in natural waters. The first step of this study was to define the experimental conditions for a LIDAR and its budget constraints on the basis of the specifications of small UAVs already available on the market. The second step consisted of a set of fluorescence LIDAR measurements on oil spills in the laboratory in order to propose a simplified discrimination method and to calculate the oil fluorescence conversion efficiency. Lastly, the main technical specifications of the payload were defined and radiometric calculations carried out to evaluate the performances of both the payload and the proposed discrimination method.

The 90 GHz radiometric imaging. [for terrain analysis

NASA Technical Reports Server (NTRS)

King, H. E.; White, J. D.; Wilson, W. J.; Mori, T. T.; Hollinger, J. P.; Troy, B. E.; Kenney, J. E.; Mcgoogan, J. T.

1976-01-01

A 90-GHz (3 mm wavelength) radiometer with a noise output fluctuation of 0.22 K (RMS), with a scanning antenna beam mirror, and the data processing system are described. Real-time radiometric imaging of terrain and man-made objects are shown. Flying at an altitude of 1500 ft a radiometer antenna with a 2 degrees halfpower beamwidth can distinguish landforms, waterways, roads, runways, bridges, ships at sea and their wakes, aircraft on runways, and athletic fields. A flight taken at an altitude of 3000 ft with approximately 2000 ft of clouds below the radiometer demonstrates the ability to distinguish bridges, rivers, marshland and other landforms even though the clouds are optically opaque. The radiometric images of a few representative scenes along with photographs of the corresponding scenes are presented to demonstrate the resolution of the imager system.

False no-growth blood cultures in pneumococcal pneumonia.

PubMed Central

Adeniyi-Jones, C C; Stevens, D L; Rasquinha, E S

1980-01-01

The growth of Streptococcus pneumoniae in commercial media containing 14C-labeled substrates was studied experimentally; the results of blood cultures that were positive for S. pneumoniae over a 14-month period were analyzed to explain no-growth but radiometrically positive blood cultures from four patients with clinically diagnosed pneumococcal pneumonia. The growth of S. pneumonoiae in aerobic blood culture vials resulted in a chocolate color in the medium. S. pneumoniae grew rapidly in both aerobic and anaerobic media, but 14CO2 evolved from the metabolism of the labeled substrates was detected only in the aerobic culture vials. Radiometric detection lagged behind growth of the organisms and was accompanied by visual changes in the media. By 24 h, the viability of the culture was on the decline; radiometric readings remained positive even when the culture had died. PMID:7419708

Estrogens, Microtubules and Aneuploidy: Mechanisms of Mammary Gland Tumorigenesis.

DTIC Science & Technology

1999-07-01

Endocrinology 136: 1718-1730. STATEMENT OF WORK Aim 1. Task 1. Establish radiometric HPLC assay for estradiol (E2) metabolism Task 2. Establish radiometric... HPLC assay for 7,12- dimethylbenz[a]anthracene (DMBA) metabolism Task 3. Characterize E2 metabolism in ACI and Sprague-Dawley (SD) rat liver...epigallocatechin gallate (EGCG) are flavonoids which have potent chemopreventive activity in a vari- ety of animal models of cancer. One proposed

Evaluation of VICAR software capability for land information support system needs. [Elk River quadrangle, Idaho

NASA Technical Reports Server (NTRS)

Yao, S. S. (Principal Investigator)

1981-01-01

A preliminary evaluation of the processing capability of the VICAR software for land information support system needs is presented. The geometric and radiometric properties of four sets of LANDSAT data taken over the Elk River, Idaho quadrangle were compared. Storage of data sets, the means of location, pixel resolution, and radiometric and geometric characteristics are described. Recommended modifications of VICAR programs are presented.

The Focusing of Light Scattered from Diffuse Reflectors Using Phase Modulation

DTIC Science & Technology

2012-03-22

was recently demonstrated for imaging otherwise hidden scene information through the collection and radiometric modeling of light reflecting off of...effectively reducing the radiometric model to that of the previously demonstrated dual photography, and leading to much-simplified results. This...angle. The fundamental geometric descriptor of reflectance is given by the bidirectional reflectance distribution function ( BRDF ) fr (θi, φi; θs, φs

Thematic mapper flight model preshipment review data package. Volume 3, part B: System data

NASA Technical Reports Server (NTRS)

1982-01-01

Procedures and results are presented for performance and systems integration tests of flight model-1 thematic mapper. Aspects considered cover electronic module integration, radiometric calibration, spectral matching, spatial coverage, radiometric calibration of the calibrator, coherent noise, dynamic square wave response, band to band registration, geometric accuracy, and self induced vibration. Thermal vacuum tests, EMI/EMS, and mass properties are included. Liens are summarized.

User's guide to the Radiometric Age Data Bank (RADB)

USGS Publications Warehouse

Zartman, Robert Eugene; Cole, James C.; Marvin, Richard F.

1976-01-01

The Radiometric Age Data Bank (RADB) has been established by the U.S. Geological Survey, as a means for collecting and organizing the estimated 100,000 radiometric ages presently published for the United States. RADB has been constructed such that a complete sample description (location, rock type, etc.), literature citation, and extensive analytical data are linked to form an independent record for each sample reported in a published work. Analytical data pertinent to the potassium-argon, rubidium-strontium, uranium-thorium-lead, lead-alpha, and fission-track methods can be accommodated, singly or in combinations, for each record. Data processing is achieved using the GIPSY program (University of Oklahoma) which maintains the data file and builds, updates, searches, and prints the records using simple yet versatile command statements. Searching and selecting records is accomplished by specifying the presence, absence, or (numeric or alphabetic) value of any element of information in the data bank, and these specifications can be logically linked to develop sophisticated searching strategies. Output is available in the form of complete data records, abbreviated tests, or columnar tabulations. Samples of data-reporting forms, GIPSY command statements, output formats, and data records are presented to illustrate the comprehensive nature and versatility of the Radiometric Age Data Bank.

Model of an optical system's influence on sensitivity of microbolometric focal plane array

NASA Astrophysics Data System (ADS)

Gogler, Sławomir; Bieszczad, Grzegorz; Zarzycka, Alicja; Szymańska, Magdalena; Sosnowski, Tomasz

2012-10-01

Thermal imagers and used therein infrared array sensors are subject to calibration procedure and evaluation of their voltage sensitivity on incident radiation during manufacturing process. The calibration procedure is especially important in so-called radiometric cameras, where accurate radiometric quantities, given in physical units, are of concern. Even though non-radiometric cameras are not expected to stand up to such elevated standards, it is still important, that the image faithfully represents temperature variations across the scene. The detectors used in thermal camera are illuminated by infrared radiation transmitted through a specialized optical system. Each optical system used influences irradiation distribution across an sensor array. In the article a model describing irradiation distribution across an array sensor working with an optical system used in the calibration set-up has been proposed. In the said method optical and geometrical considerations of the array set-up have been taken into account. By means of Monte-Carlo simulation, large number of rays has been traced to the sensor plane, what allowed to determine the irradiation distribution across the image plane for different aperture limiting configurations. Simulated results have been confronted with proposed analytical expression. Presented radiometric model allows fast and accurate non-uniformity correction to be carried out.

High-fidelity real-time maritime scene rendering

NASA Astrophysics Data System (ADS)

Shyu, Hawjye; Taczak, Thomas M.; Cox, Kevin; Gover, Robert; Maraviglia, Carlos; Cahill, Colin

2011-06-01

The ability to simulate authentic engagements using real-world hardware is an increasingly important tool. For rendering maritime environments, scene generators must be capable of rendering radiometrically accurate scenes with correct temporal and spatial characteristics. When the simulation is used as input to real-world hardware or human observers, the scene generator must operate in real-time. This paper introduces a novel, real-time scene generation capability for rendering radiometrically accurate scenes of backgrounds and targets in maritime environments. The new model is an optimized and parallelized version of the US Navy CRUISE_Missiles rendering engine. It was designed to accept environmental descriptions and engagement geometry data from external sources, render a scene, transform the radiometric scene using the electro-optical response functions of a sensor under test, and output the resulting signal to real-world hardware. This paper reviews components of the scene rendering algorithm, and details the modifications required to run this code in real-time. A description of the simulation architecture and interfaces to external hardware and models is presented. Performance assessments of the frame rate and radiometric accuracy of the new code are summarized. This work was completed in FY10 under Office of Secretary of Defense (OSD) Central Test and Evaluation Investment Program (CTEIP) funding and will undergo a validation process in FY11.

Calibrating Late Quaternary terrestrial climate signals: radiometrically dated pollen evidence from the southern Sierra Nevada, USA

USGS Publications Warehouse

Litwin, Ronald J.; Smoot, Joseph P.; Durika, Nancy J.; Smith, George I.

1999-01-01

We constructed a radiometrically calibrated proxy record of Late Pleistocene and Holocene climate change exceeding 230,000 yr duration, using pollen profiles from two cores taken through age-equivalent dry lakes - one core having greater age control (via 230Th alpha mass-spectrometry) and the other having greater stratigraphic completeness. The better dated of these two serial pollen records (Searles Lake) served as a reference section for improving the effective radiometric age control in a nearby and more complete pollen record (Owens Lake) because they: (1) are situated ~90 km apart in the same drainage system (on, and immediately leeward of, the eastern flank of the Sierra Nevada), and (2) preserved strikingly similar pollen profiles and concordant sequences of sedimentological changes. Pollen assemblages from both lakes are well preserved and diverse, and document serial changes in Late Pleistocene and Holocene plant zone distribution and composition in the westernmost Great Basin; they consist of taxa now inhabiting montane forest, woodland, steppe, and desert-scrub environments. The studied core intervals are interpreted here to be the terrestrial equivalent of marine δ18O stages 1 through 9; these pollen profiles now appear to be among the best radiometrically dated Late Pleistocene records of terrestrial climate change known.

Geometric and Radiometric Evaluation of Rasat Images

NASA Astrophysics Data System (ADS)

Cam, Ali; Topan, Hüseyin; Oruç, Murat; Özendi, Mustafa; Bayık, Çağlar

2016-06-01

RASAT, the second remote sensing satellite of Turkey, was designed and assembled, and also is being operated by TÜBİTAK Uzay (Space) Technologies Research Institute (Ankara). RASAT images in various levels are available free-of-charge via Gezgin portal for Turkish citizens. In this paper, the images in panchromatic (7.5 m GSD) and RGB (15 m GSD) bands in various levels were investigated with respect to its geometric and radiometric characteristics. The first geometric analysis is the estimation of the effective GSD as less than 1 pixel for radiometrically processed level (L1R) of both panchromatic and RGB images. Secondly, 2D georeferencing accuracy is estimated by various non-physical transformation models (similarity, 2D affine, polynomial, affine projection, projective, DLT and GCP based RFM) reaching sub-pixel accuracy using minimum 39 and maximum 52 GCPs. The radiometric characteristics are also investigated for 8 bits, estimating SNR between 21.8-42.2, and noise 0.0-3.5 for panchromatic and MS images for L1R when the sea is masked to obtain the results for land areas. The analysis show that RASAT images satisfies requirements for various applications. The research is carried out in Zonguldak test site which is mountainous and partly covered by dense forest and urban areas.

The Second SIMBIOS Radiometric Intercomparison (SIMRIC-2), March-November 2002. Volume 2

NASA Technical Reports Server (NTRS)

Meister, Gerhard; Abel, Peter; Carder, Kendall; Chapin, Albert; Clark, Dennis; Cooper, John; Davis, Curtis; English, David; Fargion, Giulietta; Feinholz, Michael;

Lidar-Radiometer Inversion Code (LIRIC) for the Retrieval of Vertical Aerosol Properties from Combined Lidar Radiometer Data: Development and Distribution in EARLINET

NASA Technical Reports Server (NTRS)

Chaikovsky, A.; Dubovik, O.; Holben, Brent N.; Bril, A.; Goloub, P.; Tanre, D.; Pappalardo, G.; Wandinger, U.; Chaikovskaya, L.; Denisov, S.;

Denni Algorithm An Enhanced Of SMS (Scan, Move and Sort) Algorithm

NASA Astrophysics Data System (ADS)

Aprilsyah Lubis, Denni; Salim Sitompul, Opim; Marwan; Tulus; Andri Budiman, M.

2017-12-01

Sorting has been a profound area for the algorithmic researchers, and many resources are invested to suggest a more working sorting algorithm. For this purpose many existing sorting algorithms were observed in terms of the efficiency of the algorithmic complexity. Efficient sorting is important to optimize the use of other algorithms that require sorted lists to work correctly. Sorting has been considered as a fundamental problem in the study of algorithms that due to many reasons namely, the necessary to sort information is inherent in many applications, algorithms often use sorting as a key subroutine, in algorithm design there are many essential techniques represented in the body of sorting algorithms, and many engineering issues come to the fore when implementing sorting algorithms., Many algorithms are very well known for sorting the unordered lists, and one of the well-known algorithms that make the process of sorting to be more economical and efficient is SMS (Scan, Move and Sort) algorithm, an enhancement of Quicksort invented Rami Mansi in 2010. This paper presents a new sorting algorithm called Denni-algorithm. The Denni algorithm is considered as an enhancement on the SMS algorithm in average, and worst cases. The Denni algorithm is compared with the SMS algorithm and the results were promising.

Rmax: A systematic approach to evaluate instrument sort performance using center stream catch☆

PubMed Central

Riddell, Andrew; Gardner, Rui; Perez-Gonzalez, Alexis; Lopes, Telma; Martinez, Lola

2015-01-01

Sorting performance can be evaluated with regard to Purity, Yield and/or Recovery of the sorted fraction. Purity is a check on the quality of the sample and the sort decisions made by the instrument. Recovery and Yield definitions vary with some authors regarding both as how efficient the instrument is at sorting the target particles from the original sample, others distinguishing Recovery from Yield, where the former is used to describe the accuracy of the instrument’s sort count. Yield and Recovery are often neglected, mostly due to difficulties in their measurement. Purity of the sort product is often cited alone but is not sufficient to evaluate sorting performance. All of these three performance metrics require re-sampling of the sorted fraction. But, unlike Purity, calculating Yield and/or Recovery calls for the absolute counting of particles in the sorted fraction, which may not be feasible, particularly when dealing with rare populations and precious samples. In addition, the counting process itself involves large errors. Here we describe a new metric for evaluating instrument sort Recovery, defined as the number of particles sorted relative to the number of original particles to be sorted. This calculation requires only measuring the ratios of target and non-target populations in the original pre-sort sample and in the waste stream or center stream catch (CSC), avoiding re-sampling the sorted fraction and absolute counting. We called this new metric Rmax, since it corresponds to the maximum expected Recovery for a particular set of instrument parameters. Rmax is ideal to evaluate and troubleshoot the optimum drop-charge delay of the sorter, or any instrument related failures that will affect sort performance. It can be used as a daily quality control check but can be particularly useful to assess instrument performance before single-cell sorting experiments. Because we do not perturb the sort fraction we can calculate Rmax during the sort process, being especially valuable to check instrument performance during rare population sorts. PMID:25747337

Examination of Chemical Adsorption and Marine Biofouling on Metal Surfaces Using Raman Scattering Techniques and Electrochemical Impedance Spectroscopy

DTIC Science & Technology

1991-03-14

analyses of labeled model compounds, such as the protein, RuBisCO (Ribulose Bisphosphate CarboxylaselOxygenase). (3) Examine adsorption of...coverages were determined radiometrically using tritiated RuBisCO . Although natural thin films were detectable using Raman scattering techniques...optical, electrochemical, and radiometric techniques and the protein RuBisCO as a model adsorbate on titanium, copper, and iron, we have been able to

The absolute radiometric calibration of the advanced very high resolution radiometer

NASA Technical Reports Server (NTRS)

Slater, P. N.; Teillet, P. M.; Ding, Y.

1988-01-01

The need for independent, redundant absolute radiometric calibration methods is discussed with reference to the Thematic Mapper. Uncertainty requirements for absolute calibration of between 0.5 and 4 percent are defined based on the accuracy of reflectance retrievals at an agricultural site. It is shown that even very approximate atmospheric corrections can reduce the error in reflectance retrieval to 0.02 over the reflectance range 0 to 0.4.

Thermal-Polarimetric and Visible Data Collection for Face Recognition

DTIC Science & Technology

2016-09-01

pixels • Spectral range: 7.5–13 μm • Analog image output: NTSC analog video • Digital image output: Firewire radiometric, 14-bit digital video to...PC The analog video was not used for this study. The radiometric, 14-bit digital data provided temperature measurement information for comparison...distribution unlimited. 18 9. References 1. Choi J, Hu S, Young SS, Davis LS. Thermal to visible face recognition. Proc. SPIE 8371, Sensing

Hyperspectral imaging spectro radiometer improves radiometric accuracy

NASA Astrophysics Data System (ADS)

Prel, Florent; Moreau, Louis; Bouchard, Robert; Bullis, Ritchie D.; Roy, Claude; Vallières, Christian; Levesque, Luc

2013-06-01

Reliable and accurate infrared characterization is necessary to measure the specific spectral signatures of aircrafts and associated infrared counter-measures protections (i.e. flares). Infrared characterization is essential to improve counter measures efficiency, improve friend-foe identification and reduce the risk of friendly fire. Typical infrared characterization measurement setups include a variety of panchromatic cameras and spectroradiometers. Each instrument brings essential information; cameras measure the spatial distribution of targets and spectroradiometers provide the spectral distribution of the emitted energy. However, the combination of separate instruments brings out possible radiometric errors and uncertainties that can be reduced with Hyperspectral imagers. These instruments combine both spectral and spatial information into the same data. These instruments measure both the spectral and spatial distribution of the energy at the same time ensuring the temporal and spatial cohesion of collected information. This paper presents a quantitative analysis of the main contributors of radiometric uncertainties and shows how a hyperspectral imager can reduce these uncertainties.

HYDICE postflight data processing

NASA Astrophysics Data System (ADS)

Aldrich, William S.; Kappus, Mary E.; Resmini, Ronald G.; Mitchell, Peter A.

1996-06-01

The hyperspectral digital imagery collection experiment (HYDICE) sensor records instrument counts for scene data, in-flight spectral and radiometric calibration sequences, and dark current levels onto an AMPEX DCRsi data tape. Following flight, the HYDICE ground data processing subsystem (GDPS) transforms selected scene data from digital numbers (DN) to calibrated radiance levels at the sensor aperture. This processing includes: dark current correction, spectral and radiometric calibration, conversion to radiance, and replacement of bad detector elements. A description of the algorithms for post-flight data processing is presented. A brief analysis of the original radiometric calibration procedure is given, along with a description of the development of the modified procedure currently used. Example data collected during the 1995 flight season, but uncorrected and processed, are shown to demonstrate the removal of apparent sensor artifacts (e.g., non-uniformities in detector response over the array) as a result of this transformation.

Reconstruction of Sky Illumination Domes from Ground-Based Panoramas

NASA Astrophysics Data System (ADS)

Coubard, F.; Lelégard, L.; Brédif, M.; Paparoditis, N.; Briottet, X.

2012-07-01

The knowledge of the sky illumination is important for radiometric corrections and for computer graphics applications such as relighting or augmented reality. We propose an approach to compute environment maps, representing the sky radiance, from a set of ground-based images acquired by a panoramic acquisition system, for instance a mobile-mapping system. These images can be affected by important radiometric artifacts, such as bloom or overexposure. A Perez radiance model is estimated with the blue sky pixels of the images, and used to compute additive corrections in order to reduce these radiometric artifacts. The sky pixels are then aggregated in an environment map, which still suffers from discontinuities on stitching edges. The influence of the quality of estimated sky radiance on the simulated light signal is measured quantitatively on a simple synthetic urban scene; in our case, the maximal error for the total sensor radiance is about 10%.

Data inversion algorithm development for the hologen occultation experiment

NASA Technical Reports Server (NTRS)

Gordley, Larry L.; Mlynczak, Martin G.

1986-01-01

The successful retrieval of atmospheric parameters from radiometric measurement requires not only the ability to do ideal radiometric calculations, but also a detailed understanding of instrument characteristics. Therefore a considerable amount of time was spent in instrument characterization in the form of test data analysis and mathematical formulation. Analyses of solar-to-reference interference (electrical cross-talk), detector nonuniformity, instrument balance error, electronic filter time-constants and noise character were conducted. A second area of effort was the development of techniques for the ideal radiometric calculations required for the Halogen Occultation Experiment (HALOE) data reduction. The computer code for these calculations must be extremely complex and fast. A scheme for meeting these requirements was defined and the algorithms needed form implementation are currently under development. A third area of work included consulting on the implementation of the Emissivity Growth Approximation (EGA) method of absorption calculation into a HALOE broadband radiometer channel retrieval algorithm.

Discrimination of fluoride and phosphate contamination in central Florida for analyses of environmental effects

NASA Technical Reports Server (NTRS)

Coker, A. E.; Marshall, R.; Thomson, F.

1972-01-01

A study was made of the spatial registration of fluoride and phosphate pollution parameters in central Florida by utilizing remote sensing techniques. Multispectral remote sensing data were collected over the area and processed to produce multispectral recognition maps. These processed data were used to map land areas and waters containing concentrations of fluoride and phosphate. Maps showing distribution of affected and unaffected vegetation were produced. In addition, the multispectral data were processed by single band radiometric slicing to produce radiometric maps used to delineate areas of high ultraviolet radiance, which indicates high fluoride concentrations. The multispectral parameter maps and radiometric maps in combination showed distinctive patterns, which are correlated with areas known to be affected by fluoride and phosphate contamination. These remote sensing techniques have the potential for regional use to assess the environmental impact of fluoride and phosphate wastes in central Florida.

Hot and cold body reference noise generators from 0 to 40 GHz

NASA Technical Reports Server (NTRS)

Hornbostel, D. H.

1974-01-01

This article describes the design, development, and analysis of exceptionally accurate radiometric noise generators from 0-40 GHz to serve as standard references. Size, weight, power, and reliability are optimized to meet the requirements of NASA air- and space-borne radiometers. The radiometric noise temperature of these noise generators is, unavoidably, calculated from measured values rather than measured directly. The absolute accuracy and stability are equal to or better than those of reliable standards available for comparison. A noise generator has been developed whose measurable properties (VSWR, line loss, thermometric temperatures) have been optimized in order to minimize the effects of the uncertainty in the calculated radiometric noise temperatures. Each measurable property is evaluated and analyzed to determine the effects of the uncertainty of the measured value. Unmeasurable properties (primarily temperature gradients) are analyzed, and reasonable precautions are designed into the noise generator to guarantee that the uncertainty of the value remains within tolerable limits.

Initial On-Orbit Radiometric Calibration of the Suomi NPP VIIRS Reflective Solar Bands

NASA Technical Reports Server (NTRS)

Lei, Ning; Wang, Zhipeng; Fulbright, Jon; Lee, Shihyan; McIntire, Jeff; Chiang, Vincent; Xiong, Jack

2012-01-01

The on-orbit radiometric response calibration of the VISible/Near InfraRed (VISNIR) and the Short-Wave InfraRed (SWIR) bands of the Visible/Infrared Imager/Radiometer Suite (VIIRS) aboard the Suomi National Polar-orbiting Partnership (NPP) satellite is carried out through a Solar Diffuser (SD). The transmittance of the SD screen and the SD's Bidirectional Reflectance Distribution Function (BRDF) are measured before launch and tabulated, allowing the VIIRS sensor aperture spectral radiance to be accurately determined. The radiometric response of a detector is described by a quadratic polynomial of the detector?s digital number (dn). The coefficients were determined before launch. Once on orbit, the coefficients are assumed to change by a common factor: the F-factor. The radiance scattered from the SD allows the determination of the F-factor. In this Proceeding, we describe the methodology and the associated algorithms in the determination of the F-factors and discuss the results.

Application of a scattered-light radiometric power meter.

PubMed

Caron, James N; DiComo, Gregory P; Ting, Antonio C; Fischer, Richard P

2011-04-01

The power measurement of high-power continuous-wave laser beams typically calls for the use of water-cooled thermopile power meters. Large thermopile meters have slow response times that can prove insufficient to conduct certain tests, such as determining the influence of atmospheric turbulence on transmitted beam power. To achieve faster response times, we calibrated a digital camera to measure the power level as the optical beam is projected onto a white surface. This scattered-light radiometric power meter saves the expense of purchasing a large area power meter and the required water cooling. In addition, the system can report the power distribution, changes in the position, and the spot size of the beam. This paper presents the theory of the scattered-light radiometric power meter and demonstrates its use during a field test at a 2.2 km optical range. © 2011 American Institute of Physics

SLC-off Landsat-7 ETM+ reflective band radiometric calibration

USGS Publications Warehouse

Markham, B.L.; Barsi, J.A.; Thome, K.J.; Barker, J.L.; Scaramuzza, P.L.; Helder, D.L.; ,

2005-01-01

Since May 31, 2003, when the scan line corrector (SLC) on the Landsat-7 ETM+ failed, the primary foci of Landsat-7 ETM+ analyses have been on understanding and attempting to fix the problem and later on developing composited products to mitigate the problem. In the meantime, the Image Assessment System personnel and vicarious calibration teams have continued to monitor the radiometric performance of the ETM+ reflective bands. The SLC failure produced no measurable change in the radiometric calibration of the ETM+ bands. No trends in the calibration are definitively present over the mission lifetime, and, if present, are less than 0.5% per year. Detector 12 in Band 7 dropped about 0.5% in response relative to the rest of the detectors in the band in May 2004 and recovered back to within 0.1% of its initial relative gain in October 2004.

Transponder-aided joint calibration and synchronization compensation for distributed radar systems.

PubMed

Wang, Wen-Qin

2015-01-01

High-precision radiometric calibration and synchronization compensation must be provided for distributed radar system due to separate transmitters and receivers. This paper proposes a transponder-aided joint radiometric calibration, motion compensation and synchronization for distributed radar remote sensing. As the transponder signal can be separated from the normal radar returns, it is used to calibrate the distributed radar for radiometry. Meanwhile, the distributed radar motion compensation and synchronization compensation algorithms are presented by utilizing the transponder signals. This method requires no hardware modifications to both the normal radar transmitter and receiver and no change to the operating pulse repetition frequency (PRF). The distributed radar radiometric calibration and synchronization compensation require only one transponder, but the motion compensation requires six transponders because there are six independent variables in the distributed radar geometry. Furthermore, a maximum likelihood method is used to estimate the transponder signal parameters. The proposed methods are verified by simulation results.

The Candela and Photometric and Radiometric Measurements

PubMed Central

Parr, Albert C.

2001-01-01

The national measurement system for photometric and radiometric quantities is presently based upon techniques that make these quantities traceable to a high-accuracy cryogenic radiometer. The redefinition of the candela in 1979 provided the opportunity for national measurement laboratories to base their photometric measurements on optical detector technology rather than on the emission from high-temperature blackbody optical sources. The ensuing technical developments of the past 20 years, including the significant improvements in cryogenic radiometer performance, have provided the opportunity to place the fundamental maintenance of photometric quantities upon absolute detector based technology as was allowed by the 1979 redefinition. Additionally, the development of improved photodetectors has had a significant impact on the methodology in most of the radiometric measurement areas. This paper will review the status of the NIST implementation of the technical changes mandated by the 1979 redefinition of the candela and its effect upon the maintenance and dissemination of optical radiation measurements. PMID:27500020

Sea surface temperature of the coastal zones of France. Heat Capacity Mapping Mission (HCMM)

NASA Technical Reports Server (NTRS)

Deschamps, P. Y.; Frouin, R.; Cassanet, G.; Verger, F. (Principal Investigator)

1979-01-01

The author has identified the following significant results. HCMM data analysis shows some mesoscale features which were previously expected to occur: summer coastal upwellings in the Gulf of Lions, tidal fronts bordering the English Channel, and cooler surface waters at the continental shelf break. The analysis of the spectral variance density spectra show that the interpretation of the data usually is limited by the HCMM radiometric performance (noise levels) at wavenumbers below 5 km in the oceanic areas; from this analysis it may also be concluded that a decrease of the radiometric noise level down to 0.1 k against an increase of the ground resolution up to 2 km would give a better optimum of the radiometric performances in the oceanic areas. HCMM data appear to be useful for analysis of the sea surface temperature field, particularly in the very coastal area by profiting from the ground resolution of 500 m.

Extreme Ultraviolet Variability Experiment (EVE) Multiple EUV Grating Spectrographs (MEGS): Radiometric Calibrations and Results

NASA Technical Reports Server (NTRS)

Hock, R. A.; Woods, T. N.; Crotser, D.; Eparvier, F. G.; Woodraska, D. L.; Chamberlin, P. C.; Woods, E. C.

2010-01-01

The NASA Solar Dynamics Observatory (SDO), scheduled for launch in early 2010, incorporates a suite of instruments including the Extreme Ultraviolet Variability Experiment (EVE). EVE has multiple instruments including the Multiple Extreme ultraviolet Grating Spectrographs (MEGS) A, B, and P instruments, the Solar Aspect Monitor (SAM), and the Extreme ultraviolet SpectroPhotometer (ESP). The radiometric calibration of EVE, necessary to convert the instrument counts to physical units, was performed at the National Institute of Standards and Technology (NIST) Synchrotron Ultraviolet Radiation Facility (SURF III) located in Gaithersburg, Maryland. This paper presents the results and derived accuracy of this radiometric calibration for the MEGS A, B, P, and SAM instruments, while the calibration of the ESP instrument is addressed by Didkovsky et al. . In addition, solar measurements that were taken on 14 April 2008, during the NASA 36.240 sounding-rocket flight, are shown for the prototype EVE instruments.

Parallel integer sorting with medium and fine-scale parallelism

NASA Technical Reports Server (NTRS)

Dagum, Leonardo

1993-01-01

Two new parallel integer sorting algorithms, queue-sort and barrel-sort, are presented and analyzed in detail. These algorithms do not have optimal parallel complexity, yet they show very good performance in practice. Queue-sort designed for fine-scale parallel architectures which allow the queueing of multiple messages to the same destination. Barrel-sort is designed for medium-scale parallel architectures with a high message passing overhead. The performance results from the implementation of queue-sort on a Connection Machine CM-2 and barrel-sort on a 128 processor iPSC/860 are given. The two implementations are found to be comparable in performance but not as good as a fully vectorized bucket sort on the Cray YMP.

Sort computation

NASA Technical Reports Server (NTRS)

Dorband, John E.

1988-01-01

Sorting has long been used to organize data in preparation for further computation, but sort computation allows some types of computation to be performed during the sort. Sort aggregation and sort distribution are the two basic forms of sort computation. Sort aggregation generates an accumulative or aggregate result for each group of records and places this result in one of the records. An aggregate operation can be any operation that is both associative and commutative, i.e., any operation whose result does not depend on the order of the operands or the order in which the operations are performed. Sort distribution copies the value from a field of a specific record in a group into that field in every record of that group.

Derivation of sorting programs

NASA Technical Reports Server (NTRS)

Varghese, Joseph; Loganantharaj, Rasiah

1990-01-01

Program synthesis for critical applications has become a viable alternative to program verification. Nested resolution and its extension are used to synthesize a set of sorting programs from their first order logic specifications. A set of sorting programs, such as, naive sort, merge sort, and insertion sort, were successfully synthesized starting from the same set of specifications.

Spin-the-bottle Sort and Annealing Sort: Oblivious Sorting via Round-robin Random Comparisons

PubMed Central

Goodrich, Michael T.

2013-01-01

We study sorting algorithms based on randomized round-robin comparisons. Specifically, we study Spin-the-bottle sort, where comparisons are unrestricted, and Annealing sort, where comparisons are restricted to a distance bounded by a temperature parameter. Both algorithms are simple, randomized, data-oblivious sorting algorithms, which are useful in privacy-preserving computations, but, as we show, Annealing sort is much more efficient. We show that there is an input permutation that causes Spin-the-bottle sort to require Ω(n2 log n) expected time in order to succeed, and that in O(n2 log n) time this algorithm succeeds with high probability for any input. We also show there is a specification of Annealing sort that runs in O(n log n) time and succeeds with very high probability. PMID:24550575

Safe sorting of GFP-transduced live cells for subsequent culture using a modified FACS vantage.

PubMed

Sørensen, T U; Gram, G J; Nielsen, S D; Hansen, J E

1999-12-01

A stream-in-air cell sorter enables rapid sorting to a high purity, but it is not well suited for sorting of infectious material due to the risk of airborne spread to the surroundings. A FACS Vantage cell sorter was modified for safe use with potentially HIV infected cells. Safety tests with bacteriophages were performed to evaluate the potential spread of biologically active material during cell sorting. Cells transduced with a retroviral vector carrying the gene for GFP were sorted on the basis of their GFP fluorescence, and GFP expression was followed during subsequent culture. The bacteriophage sorting showed that the biologically active material was confined to the sorting chamber. A failure mode simulating a nozzle blockage resulted in detectable droplets inside the sorting chamber, but no droplets could be detected when an additional air suction from the sorting chamber had been put on. The GFP transduced cells were sorted to 99% purity. Cells not expressing GFP at the time of sorting did not turn on the gene during subsequent culture. Un-sorted cells and cells sorted to be positive for GFP showed a decrease in the fraction of GFP positive cells during culture. Sorting of live infected cells can be performed safely and with no deleterious effects on vector expression using the modified FACS Vantage instrument. Copyright 1999 Wiley-Liss, Inc.

A Method for Eliminating Beam Steering Error for the Modulated Absorption-Emission Thermometry Technique

DTIC Science & Technology

2014-01-01

broadened and merged. It is also suitable for environments where broadband emitters such as soot are present. Radiometric measurements in general can be...emitters such as soot are present. Radiometric measurements in general can be made with very high accuracy. The international temperature scale (ITS...by a fitting to a model. In the case of sooting flames, the emissivity is a result of the nearly black absorption and emission features of soot

Assessment of the first radiances received from the VSSR Atmospheric Sounder (VAS) instrument

NASA Technical Reports Server (NTRS)

Chesters, D.; Uccellini, L. W.; Montgomery, H.; Mostek, A.; Robinson, W.

1981-01-01

The first orderly, calibrated radiances from the VAS-D instrument on the GOES-4 satellite are examined for: image quality, radiometric precision, radiation transfer verification at clear air radiosonde sites, regression retrieval accuracy, and mesoscale analysis features. Postlaunch problems involving calibration and data processing irregularities of scientific or operational significance are included. The radiances provide good visual and relative radiometric data for empirically conditioned retrievals of mesoscale temperature and moisture fields in clear air.

Rain attenuation studies from radiometric and rain DSD measurements at two tropical locations

NASA Astrophysics Data System (ADS)

Halder, Tuhina; Adhikari, Arpita; Maitra, Animesh

2018-05-01

Efficient use of satellite communication in tropical regions demands proper characterization of rain attenuation, particularly, in view of the available popular propagation models which are mostly based on temperate climatic data. Thus rain attenuations at frequencies 22.234, 23.834 and 31.4/30 GHz over two tropical locations Kolkata (22.57°N, 88.36°E, India) and Belem (1.45°S, 48.49° W, Brazil), have been estimated for the year 2010 and 2011, respectively. The estimation has been done utilizing ground-based disdrometer observations and radiometric measurements over Earth-space path. The results show that rain attenuation estimations from radiometric data are reliable only at low rain rates (<30 mm/h). However, the rain attenuation estimations from disdrometer measurements show good agreement with the ITU-R model, even at high rain rates (upto100 mm/h). Despite having significant variability in terms of drop size distribution (DSD), the attenuation values calculated from DSD data (disdrometer measurements) at Kolkata and Belem differ a little for the rain rates below 30 mm/h. However, the attenuation values, obtained from radiometric measurements at the two places, show significant deviations ranging from 0.54 dB to 3.2 dB up to a rain rate of 30 mm/h, on account of different rain heights, mean atmospheric temperatures and climatology of the two locations.

The structure and temperature of Pluto's Sputnik Planum using 4.2 cm radiometry

NASA Astrophysics Data System (ADS)

Linscott, Ivan; Protopapa, Silvia; Hinson, David P.; Bird, Mike; Tyler, G. Leonard; Grundy, William M.; McKinnon, William B.; Olkin, Catherine B.; Stern, S. Alan; Stansberry, John A.; Weaver, Harold A.; Pluto Composition Team, Pluto Geophysics and Geology Team, Pluto Atmospheres Team

2016-10-01

New Horizons measured the radiometric brightness temperature of Pluto at 4.2 cm, during the encounter with two scans of the spacecraft's high gain antenna shortly after closest approach. The Pluto mid-section scan included the region informally known as Sputnik Planum, now understood to be filled with nitrogen ice. The mean radiometric brightness temperature at 4.2 cm, obtained in this region is 25 K, for both Right Circular Polarization (RCP) and Left Circular Polarization (LCP), well below the sublimation temperature for nitrogen ice. Sputnik Planum was near the limb and the termination of the radiometric scan. Consequently, the thermal emission was measured obliquely over a wide range of emission angles. This geometry affords detailed modeling of the angular dependence of the thermal radiation, incorporating surface and subsurface electromagnetic scattering models as well as emissivity models of the nitrogen ice. In addition, a bistatic radar measurement detected the scattering of a 4.2 cm uplink transmitted from Earth. The bistatic specular point was within Sputnik Planum and the measurements are useful for constraining the dielectric constant as well as the surface and subsurface scattering functions of the nitrogen ice. The combination of the thermal emission's angular dependence, RCP and LCP polarization dependence, and the bistatic scattering, yields estimates of the radiometric thermal emissivity, nitrogen ice temperature and spatial correlation scales.This work is supported by the NASA New Horizons Mission.

Methods for LWIR Radiometric Calibration and Characterization

NASA Technical Reports Server (NTRS)

Ryan, Robert; Harrington, Gary; Howell, Dane; Pagnutti, Mary; Zanoni, Vicki

2002-01-01

The utility of a remote sensing system increases with its ability to retrieve surface temperature or radiance accurately. Research applications, such as sea temperature and power plant discharge, require a 0.2 C resolution or better for absolute temperature retrievals. Other applications, including agriculture water stress detection, require at least a 1 C resolution. To achieve these levels of accuracy routinely, scientists must perform laboratory and onboard calibration, as well as in-flight vicarious radiometric characterization. A common approach used for in-flight radiometric characterization incorporates a well-calibrated infrared radiometer that is mounted on a bouy and placed on a uniform water body. The radiometer monitors radiant temperature along with pressure, humidity, and temperature measurements of an associated column of atmosphere. On very still waters, however, a buoy can significantly distrub these measurements. Researchers at NASA's Stennis Space Center (SSC) have developed a novel approach of using an uncooled infrared camera mounted on a boom to quantify buoy effects. Another critical aspect of using buoy-mounted infrared radiometers is the need for extensive laboratory characterization of the instruments' radiometric sensitivity, field of view, and spectral response. Proper surface temperature retrieval also requires detailed knowledge of both the upward emission and the reflected sky emission. Recent work at SSC has demonstrated that the use of a polarization-based radiometer operating at the Brewster angle can greatly simplify temperature retrieval as well as improve overall accuracy.

Radiometric 81Kr dating identifies 120,000-year-old ice at Taylor Glacier, Antarctica

PubMed Central

Buizert, Christo; Baggenstos, Daniel; Jiang, Wei; Purtschert, Roland; Petrenko, Vasilii V.; Lu, Zheng-Tian; Müller, Peter; Kuhl, Tanner; Lee, James; Severinghaus, Jeffrey P.; Brook, Edward J.

2014-01-01

We present successful 81Kr-Kr radiometric dating of ancient polar ice. Krypton was extracted from the air bubbles in four ∼350-kg polar ice samples from Taylor Glacier in the McMurdo Dry Valleys, Antarctica, and dated using Atom Trap Trace Analysis (ATTA). The 81Kr radiometric ages agree with independent age estimates obtained from stratigraphic dating techniques with a mean absolute age offset of 6 ± 2.5 ka. Our experimental methods and sampling strategy are validated by (i) 85Kr and 39Ar analyses that show the samples to be free of modern air contamination and (ii) air content measurements that show the ice did not experience gas loss. We estimate the error in the 81Kr ages due to past geomagnetic variability to be below 3 ka. We show that ice from the previous interglacial period (Marine Isotope Stage 5e, 130–115 ka before present) can be found in abundance near the surface of Taylor Glacier. Our study paves the way for reliable radiometric dating of ancient ice in blue ice areas and margin sites where large samples are available, greatly enhancing their scientific value as archives of old ice and meteorites. At present, ATTA 81Kr analysis requires a 40–80-kg ice sample; as sample requirements continue to decrease, 81Kr dating of ice cores is a future possibility. PMID:24753606

Radiometric 81Kr dating identifies 120,000-year-old ice at Taylor Glacier, Antarctica.

PubMed

Buizert, Christo; Baggenstos, Daniel; Jiang, Wei; Purtschert, Roland; Petrenko, Vasilii V; Lu, Zheng-Tian; Müller, Peter; Kuhl, Tanner; Lee, James; Severinghaus, Jeffrey P; Brook, Edward J

2014-05-13

We present successful (81)Kr-Kr radiometric dating of ancient polar ice. Krypton was extracted from the air bubbles in four ∼350-kg polar ice samples from Taylor Glacier in the McMurdo Dry Valleys, Antarctica, and dated using Atom Trap Trace Analysis (ATTA). The (81)Kr radiometric ages agree with independent age estimates obtained from stratigraphic dating techniques with a mean absolute age offset of 6 ± 2.5 ka. Our experimental methods and sampling strategy are validated by (i) (85)Kr and (39)Ar analyses that show the samples to be free of modern air contamination and (ii) air content measurements that show the ice did not experience gas loss. We estimate the error in the (81)Kr ages due to past geomagnetic variability to be below 3 ka. We show that ice from the previous interglacial period (Marine Isotope Stage 5e, 130-115 ka before present) can be found in abundance near the surface of Taylor Glacier. Our study paves the way for reliable radiometric dating of ancient ice in blue ice areas and margin sites where large samples are available, greatly enhancing their scientific value as archives of old ice and meteorites. At present, ATTA (81)Kr analysis requires a 40-80-kg ice sample; as sample requirements continue to decrease, (81)Kr dating of ice cores is a future possibility.

Inflight Radiometric Calibration of New Horizons' Multispectral Visible Imaging Camera (MVIC)

NASA Technical Reports Server (NTRS)

Howett, C. J. A.; Parker, A. H.; Olkin, C. B.; Reuter, D. C.; Ennico, K.; Grundy, W. M.; Graps, A. L.; Harrison, K. P.; Throop, H. B.; Buie, M. W.;

From SED HI concept to Pleiades FM detection unit measurements

NASA Astrophysics Data System (ADS)

Renard, Christophe; Dantes, Didier; Neveu, Claude; Lamard, Jean-Luc; Oudinot, Matthieu; Materne, Alex

2017-11-01

The first flight model PLEIADES high resolution instrument under Thales Alenia Space development, on behalf of CNES, is currently in integration and test phases. Based on the SED HI detection unit concept, PLEIADES detection unit has been fully qualified before the integration at telescope level. The main radiometric performances have been measured on engineering and first flight models. This paper presents the results of performances obtained on the both models. After a recall of the SED HI concept, the design and performances of the main elements (charge coupled detectors, focal plane and video processing unit), detection unit radiometric performances are presented and compared to the instrument specifications for the panchromatic and multispectral bands. The performances treated are the following: - video signal characteristics, - dark signal level and dark signal non uniformity, - photo-response non uniformity, - non linearity and differential non linearity, - temporal and spatial noises regarding system definitions PLEIADES detection unit allows tuning of different functions: reference and sampling time positioning, anti-blooming level, gain value, TDI line number. These parameters are presented with their associated criteria of optimisation to achieve system radiometric performances and their sensitivities on radiometric performances. All the results of the measurements performed by Thales Alenia Space on the PLEIADES detection units demonstrate the high potential of the SED HI concept for Earth high resolution observation system allowing optimised performances at instrument and satellite levels.

Vesicoureteral reflux in young children: a study of radiometric thermometry as detection modality using an ex vivo porcine model

NASA Astrophysics Data System (ADS)

Jacobsen, Svein; Klemetsen, Øystein; Birkelund, Yngve

2012-09-01

Microwave radiometry is evaluated for renal thermometry tailored to detect the pediatric condition of vesicoureteral urine reflux (VUR) from the bladder through the ureter into the kidney. Prior to a potential reflux event, the urine is heated within the bladder by an external body contacting a hyperthermia applicator to generate a fluidic contrast temperature relative to normal body temperature. A single band, miniaturized radiometer (operating at 3.5 GHz) is connected to an electromagnetic-interference-shielded and suction-coupled elliptical antenna to receive thermal radiation from an ex vivo porcine phantom model. Brightness (radiometric) and fiberoptic temperature data are recorded for varying urine phantom reflux volumes (20-40 mL) and contrast temperatures ranging from 2 to 10 °C within the kidney phantom. The kidney phantom itself is located at 40 mm depth (skin-to-kidney center distance) and surrounded by the porcine phantom. Radiometric step responses to injection of urine simulant by a syringe are shown to be highly correlated with in situ kidney temperatures measured by fiberoptic probes. Statistically, the performance of the VUR detecting scheme is evaluated by error probabilities of making a wrong decision. Laboratory testing of the radiometric system supports the feasibility of passive non-invasive kidney thermometry for the detection of VUR classified within the two highest grades

Design and realization of sort manipulator of crystal-angle sort machine

NASA Astrophysics Data System (ADS)

Wang, Ming-shun; Chen, Shu-ping; Guan, Shou-ping; Zhang, Yao-wei

2005-12-01

It is a current tendency of development in automation technology to replace manpower with manipulators in working places where dangerous, harmful, heavy or repetitive work is involved. The sort manipulator is installed in a crystal-angle sort machine to take the place of manpower, and engaged in unloading and sorting work. It is the outcome of combing together mechanism, electric transmission, and pneumatic element and micro-controller control. The step motor makes the sort manipulator operate precisely. The pneumatic elements make the sort manipulator be cleverer. Micro-controller's software bestows some simple artificial intelligence on the sort manipulator, so that it can precisely repeat its unloading and sorting work. The combination of manipulator's zero position and step motor counting control puts an end to accumulating error in long time operation. A sort manipulator's design in the practice engineering has been proved to be correct and reliable.

A Task Analysis of the Shift from Teacher Instructions to Self-Instructions in Performing an In-Common Task.

ERIC Educational Resources Information Center

Grote, Irene; And Others

1996-01-01

Three preschoolers performed four sorts with stimulus cards--an untaught target sort and three directly taught alternating sorts considered to self-instruct the target performance. Accuracy increased first in the skill sorts and then in the untaught target sorts. All subjects generalized to new target sorts. Correct spontaneous self-instructions…

To sort or not to sort: the impact of spike-sorting on neural decoding performance.

PubMed

Todorova, Sonia; Sadtler, Patrick; Batista, Aaron; Chase, Steven; Ventura, Valérie

2014-10-01

Brain-computer interfaces (BCIs) are a promising technology for restoring motor ability to paralyzed patients. Spiking-based BCIs have successfully been used in clinical trials to control multi-degree-of-freedom robotic devices. Current implementations of these devices require a lengthy spike-sorting step, which is an obstacle to moving this technology from the lab to the clinic. A viable alternative is to avoid spike-sorting, treating all threshold crossings of the voltage waveform on an electrode as coming from one putative neuron. It is not known, however, how much decoding information might be lost by ignoring spike identity. We present a full analysis of the effects of spike-sorting schemes on decoding performance. Specifically, we compare how well two common decoders, the optimal linear estimator and the Kalman filter, reconstruct the arm movements of non-human primates performing reaching tasks, when receiving input from various sorting schemes. The schemes we tested included: using threshold crossings without spike-sorting; expert-sorting discarding the noise; expert-sorting, including the noise as if it were another neuron; and automatic spike-sorting using waveform features. We also decoded from a joint statistical model for the waveforms and tuning curves, which does not involve an explicit spike-sorting step. Discarding the threshold crossings that cannot be assigned to neurons degrades decoding: no spikes should be discarded. Decoding based on spike-sorted units outperforms decoding based on electrodes voltage crossings: spike-sorting is useful. The four waveform based spike-sorting methods tested here yield similar decoding efficiencies: a fast and simple method is competitive. Decoding using the joint waveform and tuning model shows promise but is not consistently superior. Our results indicate that simple automated spike-sorting performs as well as the more computationally or manually intensive methods used here. Even basic spike-sorting adds value to the low-threshold waveform-crossing methods often employed in BCI decoding.

To sort or not to sort: the impact of spike-sorting on neural decoding performance

NASA Astrophysics Data System (ADS)

Todorova, Sonia; Sadtler, Patrick; Batista, Aaron; Chase, Steven; Ventura, Valérie

2014-10-01

Objective. Brain-computer interfaces (BCIs) are a promising technology for restoring motor ability to paralyzed patients. Spiking-based BCIs have successfully been used in clinical trials to control multi-degree-of-freedom robotic devices. Current implementations of these devices require a lengthy spike-sorting step, which is an obstacle to moving this technology from the lab to the clinic. A viable alternative is to avoid spike-sorting, treating all threshold crossings of the voltage waveform on an electrode as coming from one putative neuron. It is not known, however, how much decoding information might be lost by ignoring spike identity. Approach. We present a full analysis of the effects of spike-sorting schemes on decoding performance. Specifically, we compare how well two common decoders, the optimal linear estimator and the Kalman filter, reconstruct the arm movements of non-human primates performing reaching tasks, when receiving input from various sorting schemes. The schemes we tested included: using threshold crossings without spike-sorting; expert-sorting discarding the noise; expert-sorting, including the noise as if it were another neuron; and automatic spike-sorting using waveform features. We also decoded from a joint statistical model for the waveforms and tuning curves, which does not involve an explicit spike-sorting step. Main results. Discarding the threshold crossings that cannot be assigned to neurons degrades decoding: no spikes should be discarded. Decoding based on spike-sorted units outperforms decoding based on electrodes voltage crossings: spike-sorting is useful. The four waveform based spike-sorting methods tested here yield similar decoding efficiencies: a fast and simple method is competitive. Decoding using the joint waveform and tuning model shows promise but is not consistently superior. Significance. Our results indicate that simple automated spike-sorting performs as well as the more computationally or manually intensive methods used here. Even basic spike-sorting adds value to the low-threshold waveform-crossing methods often employed in BCI decoding.

Sorting nexin-2 is associated with tubular elements of the early endosome, but is not essential for retromer-mediated endosome-to-TGN transport

PubMed Central

Carlton, Jez G.; Bujny, Miriam V.; Peter, Brian J.; Oorschot, Viola M. J.; Rutherford, Anna; Arkell, Rebecca S.; Klumperman, Judith; McMahon, Harvey T.; Cullen, Peter J.

2006-01-01

Summary Sorting nexins are a large family of phox-homology-domain-containing proteins that have been implicated in the control of endosomal sorting. Sorting nexin-1 is a component of the mammalian retromer complex that regulates retrieval of the cation-independent mannose 6-phosphate receptor from endosomes to the trans-Golgi network. In yeast, retromer is composed of Vps5p (the orthologue of sorting nexin-1), Vps17p (a related sorting nexin) and a cargo selective subcomplex composed of Vps26p, Vps29p and Vps35p. With the exception of Vps17p, mammalian orthologues of all yeast retromer components have been identified. For Vps17p, one potential mammalian orthologue is sorting nexin-2. Here we show that, like sorting nexin-1, sorting nexin-2 binds phosphatidylinositol 3-monophosphate and phosphatidylinositol 3,5-bisphosphate, and possesses a Bin/Amphiphysin/Rvs domain that can sense membrane curvature. However, in contrast to sorting nexin-1, sorting nexin-2 could not induce membrane tubulation in vitro or in vivo. Functionally, we show that endogenous sorting nexin-1 and sorting nexin-2 co-localise on high curvature tubular elements of the 3-phosphoinositide-enriched early endosome, and that suppression of sorting nexin-2 does not perturb the degradative sorting of receptors for epidermal growth factor or transferrin, nor the steady-state distribution of the cation-independent mannose 6-phosphate receptor. However, suppression of sorting nexin-2 results in a subtle alteration in the kinetics of cation-independent mannose 6-phosphate receptor retrieval. These data suggest that although sorting nexin-2 may be a component of the retromer complex, its presence is not essential for the regulation of endosome-to-trans Golgi network retrieval of the cation-independent mannose 6-phosphate receptor. PMID:16179610

A procedure for radiometric recalibration of Landsat 5 TM reflective-band data

USGS Publications Warehouse

Chander, G.; Haque, M.O.; Micijevic, E.; Barsi, J.A.

2010-01-01

From the Landsat program's inception in 1972 to the present, the Earth science user community has been benefiting from a historical record of remotely sensed data. The multispectral data from the Landsat 5 (L5) Thematic Mapper (TM) sensor provide the backbone for this extensive archive. Historically, the radiometric calibration procedure for the L5 TM imagery used the detectors' response to the internal calibrator (IC) on a scene-by-scene basis to determine the gain and offset for each detector. The IC system degraded with time, causing radiometric calibration errors up to 20%. In May 2003, the L5 TM data processed and distributed by the U.S. Geological Survey (USGS) Earth Resources Observation and Science Center through the National Landsat Archive Production System (NLAPS) were updated to use a lifetime lookup-table (LUT) gain model to radiometrically calibrate TM data instead of using scene-specific IC gains. Further modification of the gain model was performed in 2007. The L5 TM data processed using IC prior to the calibration update do not benefit from the recent calibration revisions. A procedure has been developed to give users the ability to recalibrate their existing level-1 products. The best recalibration results are obtained if the work-order report that was included in the original standard data product delivery is available. However, if users do not have the original work-order report, the IC trends can be used for recalibration. The IC trends were generated using the radiometric gain trends recorded in the NLAPS database. This paper provides the details of the recalibration procedure for the following: 1) data processed using IC where users have the work-order file; 2) data processed using IC where users do not have the work-order file; 3) data processed using prelaunch calibration parameters; and 4) data processed using the previous version of the LUT (e.g., LUT03) that was released before April 2, 2007.

Graphics processing unit (GPU) real-time infrared scene generation

NASA Astrophysics Data System (ADS)

Christie, Chad L.; Gouthas, Efthimios (Themie); Williams, Owen M.

2007-04-01

VIRSuite, the GPU-based suite of software tools developed at DSTO for real-time infrared scene generation, is described. The tools include the painting of scene objects with radiometrically-associated colours, translucent object generation, polar plot validation and versatile scene generation. Special features include radiometric scaling within the GPU and the presence of zoom anti-aliasing at the core of VIRSuite. Extension of the zoom anti-aliasing construct to cover target embedding and the treatment of translucent objects is described.

Remote measurement of salinity: Repeated measurements over a single flight line near the Mississippi Sound

NASA Technical Reports Server (NTRS)

Thomann, G. C.

1973-01-01

Experiments to remotely determine sea water salinity from measurements of the sea surface radiometric temperature over the Mississippi Sound were conducted. The line was flown six times at an altitude of 244 meters. The radiometric temperature of the sea surface was measured in two spectral intervals. The specifications of the equipment and the conditions under which the tests were conducted are described. Results of the tests are presented in the form of graphs.

Using Onboard Telemetry for MAVEN Orbit Determination

NASA Technical Reports Server (NTRS)

Lam, Try; Trawny, Nikolas; Lee, Clifford

2013-01-01

Determination of the spacecraft state has been traditional done using radiometric tracking data before and after the atmosphere drag pass. This paper describes our approach and results to include onboard telemetry measurements in addition to radiometric observables to refine the reconstructed trajectory estimate for the Mars Atmosphere and Volatile Evolution Mission (MAVEN). Uncertainties in the Mars atmosphere models, combined with non-continuous tracking degrade navigation accuracy, making MAVEN a key candidate for using onboard telemetry data to help complement its orbit determination process.

THEMIS Images as Art #45

NASA Technical Reports Server (NTRS)

2005-01-01

Welcome to the second annual THEMIS ART MONTH. From Jan. 31 through March 4 we will be showcasing images for their aesthetic value, rather than their science content. Portions of these images resemble things in our everyday lives, from animals to letters of the alphabet. We hope you enjoy our fanciful look at Mars!

One wonders what sort of creature needs to be kept back by this large strand of barbed wire...or perhaps this is the scar on the top of some giant Frankenstein's monster's head?

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

Design of monitoring system for mail-sorting based on the Profibus S7 series PLC

NASA Astrophysics Data System (ADS)

Zhang, W.; Jia, S. H.; Wang, Y. H.; Liu, H.; Tang, G. C.

2017-01-01

With the rapid development of the postal express, the workload of mail sorting is increasing, but the automatic technology of mail sorting is not mature enough. In view of this, the system uses Siemens S7-300 PLC as the main station controller, PLC of Siemens S7-200/400 is from the station controller, through the man-machine interface configuration software MCGS, PROFIBUS-DP communication, RFID technology and mechanical sorting hand achieve mail classification sorting monitoring. Among them, distinguish mail-sorting by scanning RFID posted in the mail electronic bar code (fixed code), the system uses the corresponding controller on the acquisition of information processing, the processed information transmit to the sorting manipulator by PROFIBUS-DP. The system can realize accurate and efficient mail sorting, which will promote the development of mail sorting technology.

Dissecting Stop Transfer versus Conservative Sorting Pathways for Mitochondrial Inner Membrane Proteins in Vivo*

PubMed Central

Park, Kwangjin; Botelho, Salomé Calado; Hong, Joonki; Österberg, Marie; Kim, Hyun

2013-01-01

Mitochondrial inner membrane proteins that carry an N-terminal presequence are sorted by one of two pathways: stop transfer or conservative sorting. However, the sorting pathway is known for only a small number of proteins, in part due to the lack of robust experimental tools with which to study. Here we present an approach that facilitates determination of inner membrane protein sorting pathways in vivo by fusing a mitochondrial inner membrane protein to the C-terminal part of Mgm1p containing the rhomboid cleavage region. We validated the Mgm1 fusion approach using a set of proteins for which the sorting pathway is known, and determined sorting pathways of inner membrane proteins for which the sorting mode was previously uncharacterized. For Sdh4p, a multispanning membrane protein, our results suggest that both conservative sorting and stop transfer mechanisms are required for insertion. Furthermore, the sorting process of Mgm1 fusion proteins was analyzed under different growth conditions and yeast mutant strains that were defective in the import motor or the m-AAA protease function. Our results show that the sorting of mitochondrial proteins carrying moderately hydrophobic transmembrane segments is sensitive to cellular conditions, implying that mitochondrial import and membrane sorting in the physiological environment may be dynamically tuned. PMID:23184936

Seminal plasma affects sperm sex sorting in boars.

PubMed

Alkmin, Diego V; Parrilla, Inmaculada; Tarantini, Tatiana; Del Olmo, David; Vazquez, Juan M; Martinez, Emilio A; Roca, Jordi

2016-04-01

Two experiments were conducted in boar semen samples to evaluate how both holding time (24h) and the presence of seminal plasma (SP) before sorting affect sperm sortability and the ability of sex-sorted spermatozoa to tolerate liquid storage. Whole ejaculate samples were divided into three aliquots immediately after collection: one was diluted (1:1, v/v) in Beltsville thawing solution (BTS; 50% SP); the SP of the other two aliquots was removed and the sperm pellets were diluted with BTS + 10% of their own SP (10% SP) or BTS alone (0% SP). The three aliquots of each ejaculate were divided into two portions, one that was processed immediately for sorting and a second that was sorted after 24h storage at 15-17°C. In the first experiment, the ability to exhibit well-defined X- and Y-chromosome-bearing sperm peaks (split) in the cytometry histogram and the subsequent sorting efficiency were assessed (20 ejaculates). In contrast with holding time, the SP proportion influenced the parameters examined, as evidenced by the higher number of ejaculates exhibiting split and better sorting efficiency (P<0.05) in semen samples with 0-10% SP compared with those with 50% SP. In a second experiment, the quality (viability, total and progressive motility) and functionality (plasma membrane fluidity and intracellular generation of reactive oxygen species) of sex-sorted spermatozoa were evaluated after 0, 72 and 120h storage at 15-17°C (10 ejaculates). Holding time and SP proportion did not influence the quality or functionality of stored sex-sorted spermatozoa. In conclusion, a holding time as long as 24h before sorting did not negatively affect sex sorting efficiency or the ability of sorted boar spermatozoa to tolerate long-term liquid storage. A high proportion of SP (50%) in the semen samples before sorting reduced the number of ejaculates to be sorted and negatively influenced the sorting efficiency, but did not affect the ability of sex-sorted spermatozoa to tolerate liquid storage.

Stochastic Model of Vesicular Sorting in Cellular Organelles

NASA Astrophysics Data System (ADS)

Vagne, Quentin; Sens, Pierre

2018-02-01

The proper sorting of membrane components by regulated exchange between cellular organelles is crucial to intracellular organization. This process relies on the budding and fusion of transport vesicles, and should be strongly influenced by stochastic fluctuations, considering the relatively small size of many organelles. We identify the perfect sorting of two membrane components initially mixed in a single compartment as a first passage process, and we show that the mean sorting time exhibits two distinct regimes as a function of the ratio of vesicle fusion to budding rates. Low ratio values lead to fast sorting but result in a broad size distribution of sorted compartments dominated by small entities. High ratio values result in two well-defined sorted compartments but sorting is exponentially slow. Our results suggest an optimal balance between vesicle budding and fusion for the rapid and efficient sorting of membrane components and highlight the importance of stochastic effects for the steady-state organization of intracellular compartments.

Identification and genetic analysis of cancer cells with PCR-activated cell sorting

PubMed Central

Eastburn, Dennis J.; Sciambi, Adam; Abate, Adam R.

2014-01-01

Cell sorting is a central tool in life science research for analyzing cellular heterogeneity or enriching rare cells out of large populations. Although methods like FACS and FISH-FC can characterize and isolate cells from heterogeneous populations, they are limited by their reliance on antibodies, or the requirement to chemically fix cells. We introduce a new cell sorting technology that robustly sorts based on sequence-specific analysis of cellular nucleic acids. Our approach, PCR-activated cell sorting (PACS), uses TaqMan PCR to detect nucleic acids within single cells and trigger their sorting. With this method, we identified and sorted prostate cancer cells from a heterogeneous population by performing >132 000 simultaneous single-cell TaqMan RT-PCR reactions targeting vimentin mRNA. Following vimentin-positive droplet sorting and downstream analysis of recovered nucleic acids, we found that cancer-specific genomes and transcripts were significantly enriched. Additionally, we demonstrate that PACS can be used to sort and enrich cells via TaqMan PCR reactions targeting single-copy genomic DNA. PACS provides a general new technical capability that expands the application space of cell sorting by enabling sorting based on cellular information not amenable to existing approaches. PMID:25030902

Comparison of Data Quality of NOAA's ISIS and SURFRAD Networks to NREL's SRRL-BMS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderberg, M.; Sengupta, M.

2014-11-01

This report provides analyses of broadband solar radiometric data quality for the National Oceanic and Atmospheric Administration's Integrated Surface Irradiance Study and Surface Radiation Budget Network (SURFRAD) solar measurement networks. The data quality of these networks is compared to that of the National Renewable Energy Laboratory's Solar Radiation Research Laboratory Baseline Measurement System (SRRL-BMS) native data resolutions and hourly averages of the data from the years 2002 through 2013. This report describes the solar radiometric data quality testing and flagging procedures and the method used to determine and tabulate data quality statistics. Monthly data quality statistics for each network weremore » plotted by year against the statistics for the SRRL-BMS. Some of the plots are presented in the body of the report, but most are in the appendix. These plots indicate that the overall solar radiometric data quality of the SURFRAD network is superior to that of the Integrated Surface Irradiance Study network and can be comparable to SRRL-BMS.« less

Reconnaissance geologic map of part of the San Isidro Quadrangle, Baja California Sur, Mexico

USGS Publications Warehouse

McLean, Hugh; Hausback, B.P.; Knapp, J.H.

1985-01-01

Mapping was done on aerial photographs and transferred, where possible, to 1:50,000-scale topographic base maps. Areas with roads were field checked; however, in the northeast part of the map area, lack of roads prevented field checks. Previous geologic surveys of parts of the map area were made by horseback in the early 1920's; reports were published by Darton (1921), Heim (1922), and Beal (1948). Subsurface data from petroleum exploration and a geologic map were incorporated in a regional study by Mina (1957). The first radiometric ages of rocks from the map area were published by Gastil and others (1979). Recently determined radiometric ages and chemical analysis of volcanic rocks were reported by Hausback (1984) and by Sawlan and Smith (1984). Our study incorporates geologic mapping with age control based on new radiometric ages as well as paleontology, Flows and tuffs were dated by the K-Ar method. Fossil ages are based on diatom and mollusk assemblages.

A multi-frequency radiometric measurement of soil moisture content over bare and vegetated fields

NASA Technical Reports Server (NTRS)

Wang, J. R.; Schmugge, T. J.; Mcmurtrey, J. E., III; Gould, W. I.; Glazar, W. S.; Fuchs, J. E. (Principal Investigator)

1981-01-01

A USDA Beltsville Agricultural Research Center site was used for an experiment in which soil moisture remote sensing over bare, grass, and alfalfa fields was conducted over a three-month period using 0.6 GHz, 1.4 GHz, and 10.6 GHz Dicke-type microwave radiometers mounted on mobile towers. Ground truth soil moisture content and ambient air and sil temperatures were obtained concurrently with the radiometric measurements. Biomass of the vegetation cover was sampled about once a week. Soil density for each of the three fields was measured several times during the course of the experiment. Results of the radiometric masurements confirm the frequency dependence of moisture sensing sensitivity reduction reported earlier. Observations over the bare, wet field show that the measured brightness temperature is lowest at 5.0 GHz and highest of 0.6 GHz frequency, a result contrary to expectation based on the estimated dielectric permittivity of soil water mixtures and current radiative transfer model in that frequency range.

Radiometric and spectral stray light correction for the portable remote imaging spectrometer (PRISM) coastal ocean sensor

NASA Astrophysics Data System (ADS)

Haag, Justin M.; Van Gorp, Byron E.; Mouroulis, Pantazis; Thompson, David R.

2017-09-01

The airborne Portable Remote Imaging Spectrometer (PRISM) instrument is based on a fast (F/1.8) Dyson spectrometer operating at 350-1050 nm and a two-mirror telescope combined with a Teledyne HyViSI 6604A detector array. Raw PRISM data contain electronic and optical artifacts that must be removed prior to radiometric calibration. We provide an overview of the process transforming raw digital numbers to calibrated radiance values. Electronic panel artifacts are first corrected using empirical relationships developed from laboratory data. The instrument spectral response functions (SRF) are reconstructed using a measurement-based optimization technique. Removal of SRF effects from the data improves retrieval of true spectra, particularly in the typically low-signal near-ultraviolet and near-infrared regions. As a final step, radiometric calibration is performed using corrected measurements of an object of known radiance. Implementation of the complete calibration procedure maximizes data quality in preparation for subsequent processing steps, such as atmospheric removal and spectral signature classification.

Radiometric calibration of hyper-spectral imaging spectrometer based on optimizing multi-spectral band selection

NASA Astrophysics Data System (ADS)

Sun, Li-wei; Ye, Xin; Fang, Wei; He, Zhen-lei; Yi, Xiao-long; Wang, Yu-peng

2017-11-01

Hyper-spectral imaging spectrometer has high spatial and spectral resolution. Its radiometric calibration needs the knowledge of the sources used with high spectral resolution. In order to satisfy the requirement of source, an on-orbit radiometric calibration method is designed in this paper. This chain is based on the spectral inversion accuracy of the calibration light source. We compile the genetic algorithm progress which is used to optimize the channel design of the transfer radiometer and consider the degradation of the halogen lamp, thus realizing the high accuracy inversion of spectral curve in the whole working time. The experimental results show the average root mean squared error is 0.396%, the maximum root mean squared error is 0.448%, and the relative errors at all wavelengths are within 1% in the spectral range from 500 nm to 900 nm during 100 h operating time. The design lays a foundation for the high accuracy calibration of imaging spectrometer.

Radiometric infrared focal plane array imaging system for thermographic applications

NASA Technical Reports Server (NTRS)

Esposito, B. J.; Mccafferty, N.; Brown, R.; Tower, J. R.; Kosonocky, W. F.

1992-01-01

This document describes research performed under the Radiometric Infrared Focal Plane Array Imaging System for Thermographic Applications contract. This research investigated the feasibility of using platinum silicide (PtSi) Schottky-barrier infrared focal plane arrays (IR FPAs) for NASA Langley's specific radiometric thermal imaging requirements. The initial goal of this design was to develop a high spatial resolution radiometer with an NETD of 1 percent of the temperature reading over the range of 0 to 250 C. The proposed camera design developed during this study and described in this report provides: (1) high spatial resolution (full-TV resolution); (2) high thermal dynamic range (0 to 250 C); (3) the ability to image rapid, large thermal transients utilizing electronic exposure control (commandable dynamic range of 2,500,000:1 with exposure control latency of 33 ms); (4) high uniformity (0.5 percent nonuniformity after correction); and (5) high thermal resolution (0.1 C at 25 C background and 0.5 C at 250 C background).

Radiometric responsivity determination for Feature Identification and Location Experiment (FILE) flown on space shuttle mission

NASA Technical Reports Server (NTRS)

Wilson, R. G.; Davis, R. E.; Wright, R. E., Jr.; Sivertson, W. E., Jr.; Bullock, G. F.

1986-01-01

A procedure was developed to obtain the radiometric (radiance) responsivity of the Feature Identification and Local Experiment (FILE) instrument in preparation for its flight on Space Shuttle Mission 41-G (November 1984). This instrument was designed to obtain Earth feature radiance data in spectral bands centered at 0.65 and 0.85 microns, along with corroborative color and color-infrared photographs, and to collect data to evaluate a technique for in-orbit autonomous classification of the Earth's primary features. The calibration process incorporated both solar radiance measurements and radiative transfer model predictions in estimating expected radiance inputs to the FILE on the Shuttle. The measured data are compared with the model predictions, and the differences observed are discussed. Application of the calibration procedure to the FILE over an 18-month period indicated a constant responsivity characteristic. This report documents the calibration procedure and the associated radiometric measurements and predictions that were part of the instrument preparation for flight.

Radiometric infrared focal plane array imaging system for thermographic applications

NASA Astrophysics Data System (ADS)

Esposito, B. J.; McCafferty, N.; Brown, R.; Tower, J. R.; Kosonocky, W. F.

1992-11-01

This document describes research performed under the Radiometric Infrared Focal Plane Array Imaging System for Thermographic Applications contract. This research investigated the feasibility of using platinum silicide (PtSi) Schottky-barrier infrared focal plane arrays (IR FPAs) for NASA Langley's specific radiometric thermal imaging requirements. The initial goal of this design was to develop a high spatial resolution radiometer with an NETD of 1 percent of the temperature reading over the range of 0 to 250 C. The proposed camera design developed during this study and described in this report provides: (1) high spatial resolution (full-TV resolution); (2) high thermal dynamic range (0 to 250 C); (3) the ability to image rapid, large thermal transients utilizing electronic exposure control (commandable dynamic range of 2,500,000:1 with exposure control latency of 33 ms); (4) high uniformity (0.5 percent nonuniformity after correction); and (5) high thermal resolution (0.1 C at 25 C background and 0.5 C at 250 C background).

A Preliminary Analysis of LANDSAT-4 Thematic Mapper Radiometric Performance

NASA Technical Reports Server (NTRS)

Justice, C.; Fusco, L.; Mehl, W.

1984-01-01

Analysis was performed to characterize the radiometry of three Thematic Mapper (TM) digital products of a scene of Arkansas. The three digital products examined were the NASA raw (BT) product, the radiometrically corrected (AT) product and the radiometrically and geometrically corrected (PT) product. The frequency distribution of the digital data; the statistical correlation between the bands; and the variability between the detectors within a band were examined on a series of image subsets from the full scene. The results are presented from one 1024 x 1024 pixel subset of Realfoot Lake, Tennessee which displayed a representative range of ground conditions and cover types occurring within the full frame image. Bands 1, 2 and 5 of the sample area are presented. The subsets were extracted from the three digital data products to cover the same geographic area. This analysis provides the first step towards a full appraisal of the TM radiometry being performed as part of the ESA/CEC contribution to the NASA/LIDQA program.

Producing Science-Ready Radar Datasets for the Retrieval of Forest Structure Parameters from Backscatter: Correcting for Terrain Topography and Changes in Vegetation Reflectivity

NASA Technical Reports Server (NTRS)

Simard, M.; Riel, Bryan; Hensley, S.; Lavalle, Marco

2011-01-01

Radar backscatter data contain both geometric and radiometric distortions due to underlying topography and the radar viewing geometry. Our objective is to develop a radiometric correction algorithm specific to the UAVSAR system configuration that would improve retrieval of forest structure parameters. UAVSAR is an airborne Lband radar capable of repeat?pass interferometry producing images with a spatial resolution of 5m. It is characterized by an electronically steerable antenna to compensate for aircraft attitude. Thus, the computation of viewing angles (i.e. look, incidence and projection) must include aircraft attitude angles (i.e. yaw, pitch and roll) in addition to the antenna steering angle. In this presentation, we address two components of radiometric correction: area projection and vegetation reflectivity. The first correction is applied by normalization of the radar backscatter by the local ground area illuminated by the radar beam. The second is a correction due to changes in vegetation reflectivity with viewing geometry.

A radiometric Bode's Law: Predictions for Uranus

NASA Technical Reports Server (NTRS)

Desch, M. D.; Kaiser, M. L.

1984-01-01

The magnetospheres of three planets, Earth, Jupiter, and Saturn, are known to be sources of intense, nonthermal radio bursts. The emissions from these sources undergo pronounced long term intensity fluctuations that are caused by the solar wind interaction with the magnetosphere of each planet. Determinations by spacecraft of the low frequency radio spectra and radiation beam geometry now permit a reliable assessment of the overall efficiency of the solar wind in stimulating these emissions. Earlier estimates of how magnetospheric radio output scales with the solar wind energy input must be revised greatly, with the result that, while the efficiency is much lower than previously thought, it is remarkably uniform from planet to planet. The formulation of a radiometric Bode's Law from which a planet's magnetic moment is estimated from its radio emission output is presented. Applying the radiometric scaling law to Uranus, the low-frequency radio power is likely to be measured by the Voyager 2 spacecraft as it approaches this planet.

Evaluation of motility, membrane status and DNA integrity of frozen-thawed bottlenose dolphin (Tursiops truncatus) spermatozoa after sex-sorting and recryopreservation.

PubMed

Montano, G A; Kraemer, D C; Love, C C; Robeck, T R; O'Brien, J K

2012-06-01

Artificial insemination (AI) with sex-sorted frozen-thawed spermatozoa has led to enhanced management of ex situ bottlenose dolphin populations. Extended distance of animals from the sorting facility can be overcome by the use of frozen-thawed, sorted and recryopreserved spermatozoa. Although one bottlenose dolphin calf had been born using sexed frozen-thawed spermatozoa derived from frozen semen, a critical evaluation of in vitro sperm quality is needed to justify the routine use of such samples in AI programs. Sperm motility parameters and plasma membrane integrity were influenced by stage of the sex-sorting process, sperm type (non-sorted and sorted) and freezing method (straw and directional) (P<0.05). After recryopreservation, sorted spermatozoa frozen with the directional freezing method maintained higher (P<0.05) motility parameters over a 24-h incubation period compared to spermatozoa frozen using straws. Quality of sperm DNA of non-sorted spermatozoa, as assessed by the sperm chromatin structure assay (SCSA), was high and remained unchanged throughout freeze-thawing and incubation processes. Though a possible interaction between Hoechst 33342 and the SCSA-derived acridine orange was observed in stained and sorted samples, the proportion of sex-sorted, recryopreserved spermatozoa exhibiting denatured DNA was low (6.6±4.1%) at 6 h after the second thawing step and remained unchanged (P>0.05) at 24 h. The viability of sorted spermatozoa was higher (P<0.05) than that of non-sorted spermatozoa across all time points after recryopreservation. Collective results indicate that bottlenose dolphin spermatozoa undergoing cryopreservation, sorting and recryopreservation are of adequate quality for use in AI.

Assessment of SNPP VIIRS VIS NIR Radiometric Calibration Stability Using Aqua MODIS and Invariant Surface Targets

NASA Technical Reports Server (NTRS)

Wu, Aisheng; Xiong, Xiaoxiong; Cao, Changyong; Chiang, Kwo-Fu

2016-01-01

The first Visible Infrared Imaging Radiometer Suite (VIIRS) is onboard the Suomi National Polar-orbiting Partnership (SNPP) satellite. As a primary sensor, it collects imagery and radiometric measurements of the land, atmosphere, cryosphere, and oceans in the spectral regions from visible (VIS) to long-wave infrared. NASA's National Polar-orbiting Partnership (NPP) VIIRS Characterization Support Team has been actively involved in the VIIRS radiometric and geometric calibration to support its Science Team Principal Investigators for their independent quality assessment of VIIRS Environmental Data Records. This paper presents the performance assessment of the radiometric calibration stability of the VIIRS VIS and NIR spectral bands using measurements from SNPP VIIRS and Aqua MODIS simultaneous nadir overpasses and over the invariant surface targets at the Libya-4 desert and Antarctic Dome Concordia snow sites. The VIIRS sensor data records (SDRs) used in this paper are reprocessed by the NASA SNPP Land Product Evaluation and Analysis Tool Element. This paper shows that the reprocessed VIIRS SDRs have been consistently calibrated from the beginning of the mission, and the calibration stability is similar to or better than MODIS. Results from different approaches indicate that the calibrations of the VIIRS VIS and NIR spectral bands are maintained to be stable to within 1% over the first three-year mission. The absolute calibration differences between VIIRS and MODIS are within 2%, with an exception for the 0.865-m band, after correction of their spectral response differences.

PCA determination of the radiometric noise of high spectral resolution infrared observations from spectral residuals: Application to IASI

NASA Astrophysics Data System (ADS)

Serio, C.; Masiello, G.; Camy-Peyret, C.; Jacquette, E.; Vandermarcq, O.; Bermudo, F.; Coppens, D.; Tobin, D.

2018-02-01

The problem of characterizing and estimating the instrumental or radiometric noise of satellite high spectral resolution infrared spectrometers directly from Earth observations is addressed in this paper. An approach has been developed, which relies on the Principal Component Analysis (PCA) with a suitable criterion to select the optimal number of PC scores. Different selection criteria have been set up and analysed, which is based on the estimation theory of Least Squares and/or Maximum Likelihood Principle. The approach is independent of any forward model and/or radiative transfer calculations. The PCA is used to define an orthogonal basis, which, in turn, is used to derive an optimal linear reconstruction of the observations. The residual vector that is the observation vector minus the calculated or reconstructed one is then used to estimate the instrumental noise. It will be shown that the use of the spectral residuals to assess the radiometric instrumental noise leads to efficient estimators, which are largely independent of possible departures of the true noise from that assumed a priori to model the observational covariance matrix. Application to the Infrared Atmospheric Sounder Interferometer (IASI) has been considered. A series of case studies has been set up, which make use of IASI observations. As a major result, the analysis confirms the high stability and radiometric performance of IASI. The approach also proved to be efficient in characterizing noise features due to mechanical micro-vibrations of the beam splitter of the IASI instrument.

Measuring inhibition of monoamine reuptake transporters by new psychoactive substances (NPS) in real-time using a high-throughput, fluorescence-based assay.

PubMed

Zwartsen, Anne; Verboven, Anouk H A; van Kleef, Regina G D M; Wijnolts, Fiona M J; Westerink, Remco H S; Hondebrink, Laura

2017-12-01

The prevalence and use of new psychoactive substances (NPS) is increasing and currently over 600 NPS exist. Many illicit drugs and NPS increase brain monoamine levels by inhibition and/or reversal of monoamine reuptake transporters (DAT, NET and SERT). This is often investigated using labor-intensive, radiometric endpoint measurements. We investigated the applicability of a novel and innovative assay that is based on a fluorescent monoamine mimicking substrate. DAT, NET or SERT-expressing human embryonic kidney (HEK293) cells were exposed to common drugs (cocaine, dl-amphetamine or MDMA), NPS (4-fluoroamphetamine, PMMA, α-PVP, 5-APB, 2C-B, 25B-NBOMe, 25I-NBOMe or methoxetamine) or the antidepressant fluoxetine. We demonstrate that this fluorescent microplate reader-based assay detects inhibition of different transporters by various drugs and discriminates between drugs. Most IC 50 values were in line with previous results from radiometric assays and within estimated human brain concentrations. However, phenethylamines showed higher IC 50 values on hSERT, possibly due to experimental differences. Compared to radiometric assays, this high-throughput fluorescent assay is uncomplicated, can measure at physiological conditions, requires no specific facilities and allows for kinetic measurements, enabling detection of transient effects. This assay is therefore a good alternative for radiometric assays to investigate effects of illicit drugs and NPS on monoamine reuptake transporters. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Microfluidic cell sorting: a review of the advances in the separation of cells from debulking to rare cell isolation.

PubMed

Shields, C Wyatt; Reyes, Catherine D; López, Gabriel P

2015-03-07

Accurate and high throughput cell sorting is a critical enabling technology in molecular and cellular biology, biotechnology, and medicine. While conventional methods can provide high efficiency sorting in short timescales, advances in microfluidics have enabled the realization of miniaturized devices offering similar capabilities that exploit a variety of physical principles. We classify these technologies as either active or passive. Active systems generally use external fields (e.g., acoustic, electric, magnetic, and optical) to impose forces to displace cells for sorting, whereas passive systems use inertial forces, filters, and adhesion mechanisms to purify cell populations. Cell sorting on microchips provides numerous advantages over conventional methods by reducing the size of necessary equipment, eliminating potentially biohazardous aerosols, and simplifying the complex protocols commonly associated with cell sorting. Additionally, microchip devices are well suited for parallelization, enabling complete lab-on-a-chip devices for cellular isolation, analysis, and experimental processing. In this review, we examine the breadth of microfluidic cell sorting technologies, while focusing on those that offer the greatest potential for translation into clinical and industrial practice and that offer multiple, useful functions. We organize these sorting technologies by the type of cell preparation required (i.e., fluorescent label-based sorting, bead-based sorting, and label-free sorting) as well as by the physical principles underlying each sorting mechanism.

Microfluidic Cell Sorting: A Review of the Advances in the Separation of Cells from Debulking to Rare Cell Isolation

PubMed Central

Shields, C. Wyatt; Reyes, Catherine D.; López, Gabriel P.

2015-01-01

Accurate and high throughput cell sorting is a critical enabling technology in molecular and cellular biology, biotechnology, and medicine. While conventional methods can provide high efficiency sorting in short timescales, advances in microfluidics have enabled the realization of miniaturized devices offering similar capabilities that exploit a variety of physical principles. We classify these technologies as either active or passive. Active systems generally use external fields (e.g., acoustic, electric, magnetic, and optical) to impose forces to displace cells for sorting, whereas passive systems use inertial forces, filters, and adhesion mechanisms to purify cell populations. Cell sorting on microchips provides numerous advantages over conventional methods by reducing the size of necessary equipment, eliminating potentially biohazardous aerosols, and simplifying the complex protocols commonly associated with cell sorting. Additionally, microchip devices are well suited for parallelization, enabling complete lab-on-a-chip devices for cellular isolation, analysis, and experimental processing. In this review, we examine the breadth of microfluidic cell sorting technologies, while focusing on those that offer the greatest potential for translation into clinical and industrial practice and that offer multiple, useful functions. We organize these sorting technologies by the type of cell preparation required (i.e., fluorescent label-based sorting, bead-based sorting, and label-free sorting) as well as by the physical principles underlying each sorting mechanism. PMID:25598308

A Binary Array Asynchronous Sorting Algorithm with Using Petri Nets

NASA Astrophysics Data System (ADS)

Voevoda, A. A.; Romannikov, D. O.

2017-01-01

Nowadays the tasks of computations speed-up and/or their optimization are actual. Among the approaches on how to solve these tasks, a method applying approaches of parallelization and asynchronization to a sorting algorithm is considered in the paper. The sorting methods are ones of elementary methods and they are used in a huge amount of different applications. In the paper, we offer a method of an array sorting that based on a division into a set of independent adjacent pairs of numbers and their parallel and asynchronous comparison. And this one distinguishes the offered method from the traditional sorting algorithms (like quick sorting, merge sorting, insertion sorting and others). The algorithm is implemented with the use of Petri nets, like the most suitable tool for an asynchronous systems description.

A Quality Sorting of Fruit Using a New Automatic Image Processing Method

NASA Astrophysics Data System (ADS)

Amenomori, Michihiro; Yokomizu, Nobuyuki

This paper presents an innovative approach for quality sorting of objects such as apples sorting in an agricultural factory, using an image processing algorithm. The objective of our approach are; firstly to sort the objects by their colors precisely; secondly to detect any irregularity of the colors surrounding the apples efficiently. An experiment has been conducted and the results have been obtained and compared with that has been preformed by human sorting process and by color sensor sorting devices. The results demonstrate that our approach is capable to sort the objects rapidly and the percentage of classification valid rate was 100 %.

Performance evaluation of firefly algorithm with variation in sorting for non-linear benchmark problems

NASA Astrophysics Data System (ADS)

Umbarkar, A. J.; Balande, U. T.; Seth, P. D.

2017-06-01

The field of nature inspired computing and optimization techniques have evolved to solve difficult optimization problems in diverse fields of engineering, science and technology. The firefly attraction process is mimicked in the algorithm for solving optimization problems. In Firefly Algorithm (FA) sorting of fireflies is done by using sorting algorithm. The original FA is proposed with bubble sort for ranking the fireflies. In this paper, the quick sort replaces bubble sort to decrease the time complexity of FA. The dataset used is unconstrained benchmark functions from CEC 2005 [22]. The comparison of FA using bubble sort and FA using quick sort is performed with respect to best, worst, mean, standard deviation, number of comparisons and execution time. The experimental result shows that FA using quick sort requires less number of comparisons but requires more execution time. The increased number of fireflies helps to converge into optimal solution whereas by varying dimension for algorithm performed better at a lower dimension than higher dimension.

Virtual and remote experiments for radiometric and photometric measurements

NASA Astrophysics Data System (ADS)

Thoms, L.-J.; Girwidz, R.

2017-09-01

The analysis of spectra is fundamental to our modern understanding of wave optics and colour perception. Since spectrometers are expensive, and accurate calibration is necessary to achieve high quality spectra, we developed a remote lab on optical spectrometry. With this tool, students can carry out real experiments over the Internet. In this article the pros and cons of remote labs, the physical background of optical spectrometry, and the development and use of a radiometric remote lab for higher education are discussed. The remote lab is freely accessible to everyone at http://virtualremotelab.net.

Radiometric calibration of SPOT 2 HRV - A comparison of three methods

NASA Technical Reports Server (NTRS)

Biggar, Stuart F.; Dinguirard, Magdeleine C.; Gellman, David I.; Henry, Patrice; Jackson, Ray D.; Moran, M. S.; Slater, Philip N.

1991-01-01

Three methods for determining an absolute radiometric calibration of a spacecraft optical sensor are compared. They are the well-known reflectance-based and radiance-based methods and a new method based on measurements of the ratio of diffuse-to-global irradiance at the ground. The latter will be described in detail and the comparison of the three approaches will be made with reference to the SPOT-2 HRV cameras for a field campaign 1990-06-19 through 1990-06-24 at the White Sands Missile Range in New Mexico.

Radiometric analysis of photographic data by the effective exposure method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Constantine, B J

1972-04-01

The effective exposure method provides for radiometric analysis of photographic data. A three-dimensional model, where density is a function of energy and wavelength, is postulated to represent the film response function. Calibration exposures serve to eliminate the other factors which affect image density. The effective exposure causing an image can be determined by comparing the image density with that of a calibration exposure. If the relative spectral distribution of the source is known, irradiance and/or radiance can be unfolded from the effective exposure expression.

Impact of vane size and separation on radiometric forces for microactuation

NASA Astrophysics Data System (ADS)

Gimelshein, Natalia; Gimelshein, Sergey; Ketsdever, Andrew; Selden, Nathaniel

2011-04-01

A kinetic approach is used to study the feasibility of increasing the efficiency of microactuators that use radiometric force through etching holes in a single radiometer vane. It has been shown that a radiometer that consists of small vanes is capable of producing at least an order of magnitude larger force than a single-vane radiometer that takes up the same area. The optimum gap between the vanes is found to be slightly smaller than the vane size, with the optimum Knudsen number of about 0.05 based on the vane height.

Apparatus description and data analysis of a radiometric technique for measurements of spectral and total normal emittance

NASA Technical Reports Server (NTRS)

Edwards, S. F.; Kantsios, A. G.; Voros, J. P.; Stewart, W. F.

1975-01-01

The development of a radiometric technique for determining the spectral and total normal emittance of materials heated to temperatures of 800, 1100, and 1300 K by direct comparison with National Bureau of Standards (NBS) reference specimens is discussed. Emittances are measured over the spectral range of 1 to 15 microns and are statistically compared with NBS reference specimens. Results are included for NBS reference specimens, Rene 41, alundum, zirconia, AISI type 321 stainless steel, nickel 201, and a space-shuttle reusable surface insulation.

Learning cellular sorting pathways using protein interactions and sequence motifs.

PubMed

Lin, Tien-Ho; Bar-Joseph, Ziv; Murphy, Robert F

2011-11-01

Proper subcellular localization is critical for proteins to perform their roles in cellular functions. Proteins are transported by different cellular sorting pathways, some of which take a protein through several intermediate locations until reaching its final destination. The pathway a protein is transported through is determined by carrier proteins that bind to specific sequence motifs. In this article, we present a new method that integrates protein interaction and sequence motif data to model how proteins are sorted through these sorting pathways. We use a hidden Markov model (HMM) to represent protein sorting pathways. The model is able to determine intermediate sorting states and to assign carrier proteins and motifs to the sorting pathways. In simulation studies, we show that the method can accurately recover an underlying sorting model. Using data for yeast, we show that our model leads to accurate prediction of subcellular localization. We also show that the pathways learned by our model recover many known sorting pathways and correctly assign proteins to the path they utilize. The learned model identified new pathways and their putative carriers and motifs and these may represent novel protein sorting mechanisms. Supplementary results and software implementation are available from http://murphylab.web.cmu.edu/software/2010_RECOMB_pathways/.

Birth of kids after artificial insemination with sex-sorted, frozen-thawed goat spermatozoa.

PubMed

Bathgate, R; Mace, N; Heasman, K; Evans, G; Maxwell, W M C; de Graaf, S P

2013-12-01

Successful sex-sorting of goat spermatozoa and subsequent birth of pre-sexed kids have yet to be reported. As such, a series of experiments were conducted to develop protocols for sperm-sorting (using a modified flow cytometer, MoFlo SX(®) ) and cryopreservation of goat spermatozoa. Saanen goat spermatozoa (n = 2 males) were (i) collected into Salamon's or Tris catch media post-sorting and (ii) frozen in Tris-citrate-glucose media supplemented with 5, 10 or 20% egg yolk in (iii) 0.25 ml pellets on dry ice or 0.25 ml straws in a controlled-rate freezer. Post-sort and post-thaw sperm quality were assessed by motility (CASA), viability and acrosome integrity (PI/FITC-PNA). Sex-sorted goat spermatozoa frozen in pellets displayed significantly higher post-thaw motility and viability than spermatozoa frozen in straws. Catch media and differing egg yolk concentration had no effect on the sperm parameters tested. The in vitro and in vivo fertility of sex-sorted goat spermatozoa produced with this optimum protocol were then tested by means of a heterologous ova binding assay and intrauterine artificial insemination of Saanen goat does, respectively. Sex-sorted goat spermatozoa bound to sheep ova zona pellucidae in similar numbers (p > 0.05) to non-sorted goat spermatozoa, non-sorted ram spermatozoa and sex-sorted ram spermatozoa. Following intrauterine artificial insemination with sex-sorted spermatozoa, 38% (5/13) of does kidded with 83% (3/5) of kids being of the expected sex. Does inseminated with non-sorted spermatozoa achieved a 50% (3/6) kidding rate and a sex ratio of 3 : 1 (F : M). This study demonstrates for the first time that goat spermatozoa can be sex-sorted by flow cytometry, successfully frozen and used to produce pre-sexed kids. © 2013 Blackwell Verlag GmbH.

Sorting drops and cells with acoustics: acoustic microfluidic fluorescence-activated cell sorter.

PubMed

Schmid, Lothar; Weitz, David A; Franke, Thomas

2014-10-07

We describe a versatile microfluidic fluorescence-activated cell sorter that uses acoustic actuation to sort cells or drops at ultra-high rates. Our acoustic sorter combines the advantages of traditional fluorescence-activated cell (FACS) and droplet sorting (FADS) and is applicable for a multitude of objects. We sort aqueous droplets, at rates as high as several kHz, into two or even more outlet channels. We can also sort cells directly from the medium without prior encapsulation into drops; we demonstrate this by sorting fluorescently labeled mouse melanoma cells in a single phase fluid. Our acoustic microfluidic FACS is compatible with standard cell sorting cytometers, yet, at the same time, enables a rich variety of more sophisticated applications.

Surface acoustic wave actuated cell sorting (SAWACS).

PubMed

Franke, T; Braunmüller, S; Schmid, L; Wixforth, A; Weitz, D A

2010-03-21

We describe a novel microfluidic cell sorter which operates in continuous flow at high sorting rates. The device is based on a surface acoustic wave cell-sorting scheme and combines many advantages of fluorescence activated cell sorting (FACS) and fluorescence activated droplet sorting (FADS) in microfluidic channels. It is fully integrated on a PDMS device, and allows fast electronic control of cell diversion. We direct cells by acoustic streaming excited by a surface acoustic wave which deflects the fluid independently of the contrast in material properties of deflected objects and the continuous phase; thus the device underlying principle works without additional enhancement of the sorting by prior labelling of the cells with responsive markers such as magnetic or polarizable beads. Single cells are sorted directly from bulk media at rates as fast as several kHz without prior encapsulation into liquid droplet compartments as in traditional FACS. We have successfully directed HaCaT cells (human keratinocytes), fibroblasts from mice and MV3 melanoma cells. The low shear forces of this sorting method ensure that cells survive after sorting.

Diurnal remote sensing of coastal/oceanic waters: a radiometric analysis for Geostationary Coastal and Air Pollution Events.

PubMed

Pahlevan, Nima; Lee, Zhongping; Hu, Chuanmin; Schott, John R

2014-02-01

Optical remote sensing systems aboard geostationary platforms can provide high-frequency observations of bio-optical properties in dynamical coastal/oceanic waters. From the end-user standpoint, it is recognized that the fidelity of daily science products relies heavily on the radiometric sensitivity/performance of the imaging system. This study aims to determine the theoretical detection limits for bio-optical properties observed diurnally from a geostationary orbit. The analysis is based upon coupled radiative transfer simulations and the minimum radiometric requirements defined for the GEOstationary Coastal and Air Pollution Events (GEO-CAPE) mission. The diurnal detection limits are found for the optically active constituents of water, including near-surface concentrations of chlorophyll-a (CHL) and total suspended solids (TSS), and the absorption of colored dissolved organic matter (aCDOM). The diurnal top-of-atmosphere radiance (Lt) is modeled for several locations across the field of regard (FOR) to investigate the radiometric sensitivity at different imaging geometries. It is found that, in oceanic waters (CHL=0.07  mg/m3), detecting changes smaller than 0.01  mg/m3 in CHL is feasible for all locations and hours except for late afternoon observations on the edge of the FOR. For more trophic/turbid waters (0.6

Absolute Radiometric Calibration of the GÖKTÜRK-2 Satellite Sensor Using Tuz GÖLÜ (landnet Site) from Ndvi Perspective

NASA Astrophysics Data System (ADS)

Sakarya, Ufuk; Hakkı Demirhan, İsmail; Seda Deveci, Hüsne; Teke, Mustafa; Demirkesen, Can; Küpçü, Ramazan; Feray Öztoprak, A.; Efendioğlu, Mehmet; Fehmi Şimşek, F.; Berke, Erdinç; Zübeyde Gürbüz, Sevgi

2016-06-01

TÜBİTAK UZAY has conducted a research study on the use of space-based satellite resources for several aspects of agriculture. Especially, there are two precision agriculture related projects: HASSAS (Widespread application of sustainable precision agriculture practices in Southeastern Anatolia Project Region (GAP) Project) and AKTAR (Smart Agriculture Feasibility Project). The HASSAS project aims to study development of precision agriculture practice in GAP region. Multi-spectral satellite imagery and aerial hyperspectral data along with ground measurements was collected to analyze data in an information system. AKTAR aims to develop models for irrigation, fertilization and spectral signatures of crops in Inner Anatolia. By the end of the project precision agriculture practices to control irrigation, fertilization, pesticide and estimation of crop yield will be developed. Analyzing the phenology of crops using NDVI is critical for the projects. For this reason, absolute radiometric calibration of the Red and NIR bands in space-based satellite sensors is an important issue. The Göktürk-2 satellite is an earth observation satellite which was designed and built in Turkey and was launched in 2012. The Göktürk-2 satellite sensor has a resolution 2.5 meters in panchromatic and 5 meters in R/G/B/NIR bands. The absolute radiometric calibration of the Göktürk-2 satellite sensor was performed via the ground-based measurements - spectra-radiometer, sun photometer, and meteorological station- in Tuz Gölü cal/val site in 2015. In this paper, the first ground-based absolute radiometric calibration results of the Göktürk-2 satellite sensor using Tuz Gölü is demonstrated. The absolute radiometric calibration results of this paper are compared with the published cross-calibration results of the Göktürk-2 satellite sensor utilizing Landsat 8 imagery. According to the experimental comparison results, the Göktürk-2 satellite sensor coefficients for red and NIR bands estimated in this work sustained to agree within 2% of calibration coefficients estimated in the cross-calibration results.

Dating human skeletal remains using 90Sr and 210Pb: case studies.

PubMed

Schrag, Bettina; Uldin, Tanya; Mangin, Patrice; Bochud, François; Froidevaux, Pascal

2014-01-01

In legal medicine, the post mortem interval (PMI) of interest covers the last 50 years. When only human skeletal remains are found, determining the PMI currently relies mostly on the experience of the forensic anthropologist, with few techniques available to help. Recently, several radiometric methods have been proposed to reveal PMI. For instance, (14)C and (90)Sr bomb pulse dating covers the last 60 years and give reliable PMI when teeth or bones are available. (232)Th series dating has also been proposed but requires a large amount of bones. In addition, (210)Pb dating is promising but is submitted to diagenesis and individual habits like smoking that must be handled carefully. Here we determine PMI on 29 cases of forensic interest using (90)Sr bomb pulse. In 12 cases, (210)Pb dating was added to narrow the PMI interval. In addition, anthropological investigations were carried out on 15 cases to confront anthropological expertise to the radiometric method. Results show that 10 of the 29 cases can be discarded as having no forensic interest (PMI>50 years) based only on the (90)Sr bomb pulse dating. For 10 other cases, the additional (210)Pb dating restricts the PMI uncertainty to a few years. In 15 cases, anthropological investigations corroborate the radiometric PMI. This study also shows that diagenesis and inter-individual difference in radionuclide uptake represent the main sources of uncertainty in the PMI determination using radiometric methods. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

BOREAS TE-18, 30-m, Radiometrically Rectified Landsat TM Imagery

NASA Technical Reports Server (NTRS)

Hall, Forrest G. (Editor); Knapp, David

2000-01-01

The BOREAS TE-18 team used a radiometric rectification process to produce standardized DN values for a series of Landsat TM images of the BOREAS SSA and NSA in order to compare images that were collected under different atmospheric conditions. The images for each study area were referenced to an image that had very clear atmospheric qualities. The reference image for the SSA was collected on 02-Sep-1994, while the reference image for the NSA was collected on 21-Jun-1995. the 23 rectified images cover the period of 07-Jul-1985 to 18 Sep-1994 in the SSA and from 22-Jun-1984 to 09-Jun-1994 in the NSA. Each of the reference scenes had coincident atmospheric optical thickness measurements made by RSS-11. The radiometric rectification process is described in more detail by Hall et al. (199 1). The original Landsat TM data were received from CCRS for use in the BOREAS project. The data are stored in binary image-format files. Due to the nature of the radiometric rectification process and copyright issues, these full-resolution images may not be publicly distributed. However, a spatially degraded 60-m resolution version of the images is available on the BOREAS CD-ROM series. See Sections 15 and 16 for information about how to possibly acquire the full resolution data. Information about the full-resolution images is provided in an inventory listing on the CD-ROMs. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Activity Archive Center (DAAC).

Radiometric calibration of the Landsat MSS sensor series

USGS Publications Warehouse

Helder, Dennis L.; Karki, Sadhana; Bhatt, Rajendra; Micijevik, Esad; Aaron, David; Jasinski, Benjamin

2012-01-01

Multispectral remote sensing of the Earth using Landsat sensors was ushered on July 23, 1972, with the launch of Landsat-1. Following that success, four more Landsat satellites were launched, and each of these carried the Multispectral Scanner System (MSS). These five sensors provided the only consistent multispectral space-based imagery of the Earth's surface from 1972 to 1982. This work focuses on developing both a consistent and absolute radiometric calibration of this sensor system. Cross-calibration of the MSS was performed through the use of pseudoinvariant calibration sites (PICSs). Since these sites have been shown to be stable for long periods of time, changes in MSS observations of these sites were attributed to changes in the sensors themselves. In addition, simultaneous data collections were available for some MSS sensor pairs, and these were also used for cross-calibration. Results indicated substantial differences existed between instruments, up to 16%, and these were reduced to 5% or less across all MSS sensors and bands. Lastly, this paper takes the calibration through the final step and places the MSS sensors on an absolute radiometric scale. The methodology used to achieve this was based on simultaneous data collections by the Landsat-5 MSS and Thematic Mapper (TM) instruments. Through analysis of image data from a PICS location and through compensating for the spectral differences between the two instruments, the Landsat-5 MSS sensor was placed on an absolute radiometric scale based on the Landsat-5 TM sensor. Uncertainties associated with this calibration are considered to be less than 5%.

Inter-laboratory comparison of radiometric culture for Mycobacterium avium subsp. paratuberculosis using raw milk from known infected herds and individual dairy cattle in Victoria.

PubMed

Ridge, S E; Andreata, S; Jones, K; Cantlon, K; Francis, B; Florisson, N; Gwozdz, J

2010-07-01

To compare the results of radiometric culture conducted in three Australian laboratories for Mycobacterium avium subsp. paratuberculosis (Mptb) using bulk vat and individual animal milk samples. Milk samples were collected from 15 cows exhibiting clinical signs of Johne's disease, and subsequently confirmed as infected with Mptb, and from the bulk milk vats on 91 farms running herds known to be infected with Mptb. Each milk sample was divided into three equivalent samples and one of each of the replicates was forwarded to the three participating laboratories. The identity and nature of the samples was protected from the study collaborators. The laboratories processed the samples and undertook radiometric culture for Mptb using their standard method. Results of testing were provided to the principal investigator for collation and analysis. In total, 2 (2.2%) of 91 vat-milk samples and 8 (53.3%) of 15 individual cows' milk samples returned positive radiometric milk culture results. Only one sample, from a clinical case of Johne's disease, was identified as positive by more than one laboratory. There were differences in the absolute frequency with which Mptb was identified in the milk samples by the collaborating laboratories. Mptb was cultured from a very small percentage of Australian raw bulk milk samples sourced from known infected herds. By contrast, Mptb was successfully cultured from half of the milk samples collected from clinically affected cows. There was no statistical difference between laboratories in the proportion of vat samples or individual animal milk samples in which Mptb was detected.

Research of grasping algorithm based on scara industrial robot

NASA Astrophysics Data System (ADS)

Peng, Tao; Zuo, Ping; Yang, Hai

2018-04-01

As the tobacco industry grows, facing the challenge of the international tobacco giant, efficient logistics service is one of the key factors. How to complete the tobacco sorting task of efficient economy is the goal of tobacco sorting and optimization research. Now the cigarette distribution system uses a single line to carry out the single brand sorting task, this article adopts a single line to realize the cigarette sorting task of different brands. Using scara robot special algorithm for sorting and packaging, the optimization scheme significantly enhances the indicators of smoke sorting system. Saving labor productivity, obviously improve production efficiency.

Learning Cellular Sorting Pathways Using Protein Interactions and Sequence Motifs

PubMed Central

Lin, Tien-Ho; Bar-Joseph, Ziv

2011-01-01

Abstract Proper subcellular localization is critical for proteins to perform their roles in cellular functions. Proteins are transported by different cellular sorting pathways, some of which take a protein through several intermediate locations until reaching its final destination. The pathway a protein is transported through is determined by carrier proteins that bind to specific sequence motifs. In this article, we present a new method that integrates protein interaction and sequence motif data to model how proteins are sorted through these sorting pathways. We use a hidden Markov model (HMM) to represent protein sorting pathways. The model is able to determine intermediate sorting states and to assign carrier proteins and motifs to the sorting pathways. In simulation studies, we show that the method can accurately recover an underlying sorting model. Using data for yeast, we show that our model leads to accurate prediction of subcellular localization. We also show that the pathways learned by our model recover many known sorting pathways and correctly assign proteins to the path they utilize. The learned model identified new pathways and their putative carriers and motifs and these may represent novel protein sorting mechanisms. Supplementary results and software implementation are available from http://murphylab.web.cmu.edu/software/2010_RECOMB_pathways/. PMID:21999284

A New Algorithm Using the Non-Dominated Tree to Improve Non-Dominated Sorting.

PubMed

Gustavsson, Patrik; Syberfeldt, Anna

2018-01-01

Non-dominated sorting is a technique often used in evolutionary algorithms to determine the quality of solutions in a population. The most common algorithm is the Fast Non-dominated Sort (FNS). This algorithm, however, has the drawback that its performance deteriorates when the population size grows. The same drawback applies also to other non-dominating sorting algorithms such as the Efficient Non-dominated Sort with Binary Strategy (ENS-BS). An algorithm suggested to overcome this drawback is the Divide-and-Conquer Non-dominated Sort (DCNS) which works well on a limited number of objectives but deteriorates when the number of objectives grows. This article presents a new, more efficient algorithm called the Efficient Non-dominated Sort with Non-Dominated Tree (ENS-NDT). ENS-NDT is an extension of the ENS-BS algorithm and uses a novel Non-Dominated Tree (NDTree) to speed up the non-dominated sorting. ENS-NDT is able to handle large population sizes and a large number of objectives more efficiently than existing algorithms for non-dominated sorting. In the article, it is shown that with ENS-NDT the runtime of multi-objective optimization algorithms such as the Non-Dominated Sorting Genetic Algorithm II (NSGA-II) can be substantially reduced.

The influence of tissue layering on microwave thermographic measurements.

PubMed

Hawley, M S; Conway, J; Anderson, A P; Cudd, P A

1988-01-01

Non-invasive thermal imaging and temperature measurement by microwave radiometry has been investigated for medical diagnostic applications and monitoring hyperthermia treatment of cancer, in the context of heterogeneous body structure. The temperature measured by a radiometer is a function of the emission and propagation of microwaves in tissue and the receiving characteristics of the radiometric probe. Propagation of microwaves in lossy media was analysed by a spectral diffraction approach. Extension of this technique via a cascade transmission line model provides an efficient algorithm for predicting the field patterns of aperture antennas contacting multi-layered tissue. A coherent radiative transfer analysis was used to relate the field pattern of a radiating antenna to its receiving characteristics when used as a radiometer probe, leading to a method for simulating radiometric data. Measurements and simulations were used to assess the effect of overlying fat layers upon radiometer response to temperature hot spots in muscle-type media. Results suggest that dielectric layering in tissue greatly influences measured temperatures and should be accounted for in the interpretation of radiometric data.

Photometric stability of the lunar surface

USGS Publications Warehouse

Kieffer, H.H.

1997-01-01

The rate at which cratering events currently occur on the Moon is considered in light of their influence on the use of the Moon as a radiometric standard. The radiometric effect of small impact events is determined empirically from the study of Clementine images. Events that would change the integral brightness of the moon by 1% are expected once per 1.4 Gyr. Events that cause a 1% shift in one pixel for low Earth-orbiting instruments with a 1-km nadir field of view are expected approximately once each 43 Myr. Events discernible at 1% radiometric resolution with a 5 arc-sec telescope resolution correspond to crater diameters of approximately 210 m and are expected once every 200 years. These rates are uncertain by a factor of two. For a fixed illumination and observation geometry, the Moon can be considered photometrically stable to 1 ?? 10-8per annum for irradiance, and 1 ?? 10-7per annum for radiance at a resolution common for spacecraft imaging instruments, exceeding reasonable instrument goals by six orders of magnitude. ?? 1997 Academic Press.

Imager-to-Radiometer In-flight Cross Calibration: RSP Radiometric Comparison with Airborne and Satellite Sensors

NASA Technical Reports Server (NTRS)

McCorkel, Joel; Cairns, Brian; Wasilewski, Andrzej

2016-01-01

This work develops a method to compare the radiometric calibration between a radiometer and imagers hosted on aircraft and satellites. The radiometer is the airborne Research Scanning Polarimeter (RSP), which takes multi-angle, photo-polarimetric measurements in several spectral channels. The RSP measurements used in this work were coincident with measurements made by the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS), which was on the same aircraft. These airborne measurements were also coincident with an overpass of the Landsat 8 Operational Land Imager (OLI). First we compare the RSP and OLI radiance measurements to AVIRIS since the spectral response of the multispectral instruments can be used to synthesize a spectrally equivalent signal from the imaging spectrometer data. We then explore a method that uses AVIRIS as a transfer between RSP and OLI to show that radiometric traceability of a satellite-based imager can be used to calibrate a radiometer despite differences in spectral channel sensitivities. This calibration transfer shows agreement within the uncertainty of both the various instruments for most spectral channels.

Empirical Corrections for MISR Calibration Temporal Trends, Point-Spread Function, Flat-Fielding, and Ghosting

NASA Astrophysics Data System (ADS)

Limbacher, J.; Kahn, R. A.

2015-12-01

MISR aerosol optical depth retrievals are fairly robust to small radiometric calibration artifacts, due to the multi-angle observations. However, even small errors in the MISR calibration, especially structured artifacts in the imagery, have a disproportionate effect on the retrieval of aerosol properties from these data. Using MODIS, POLDER-3, AERONET, MAN, and MISR lunar images, we diagnose and correct various calibration and radiometric artifacts found in the MISR radiance (Level 1) data, using empirical image analysis. The calibration artifacts include temporal trends in MISR top-of-atmosphere reflectance at relatively stable desert sites and flat-fielding artifacts detected by comparison to MODIS over bright, low-contrast scenes. The radiometric artifacts include ghosting (as compared to MODIS, POLDER-3, and forward model results) and point-spread function mischaracterization (using the MISR lunar data and MODIS). We minimize the artifacts to the extent possible by parametrically modeling the artifacts and then removing them from the radiance (reflectance) data. Validation is performed using non-training scenes (reflectance comparison), and also by using the MISR Research Aerosol retrieval algorithm results compared to MAN and AERONET.

A Method to Estimate Uncertainty in Radiometric Measurement Using the Guide to the Expression of Uncertainty in Measurement (GUM) Method; NREL (National Renewable Energy Laboratory)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Habte, A.; Sengupta, M.; Reda, I.

Radiometric data with known and traceable uncertainty is essential for climate change studies to better understand cloud radiation interactions and the earth radiation budget. Further, adopting a known and traceable method of estimating uncertainty with respect to SI ensures that the uncertainty quoted for radiometric measurements can be compared based on documented methods of derivation.Therefore, statements about the overall measurement uncertainty can only be made on an individual basis, taking all relevant factors into account. This poster provides guidelines and recommended procedures for estimating the uncertainty in calibrations and measurements from radiometers. The approach follows the Guide to the Expressionmore » of Uncertainty in Measurement (GUM). derivation.Therefore, statements about the overall measurement uncertainty can only be made on an individual basis, taking all relevant factors into account. This poster provides guidelines and recommended procedures for estimating the uncertainty in calibrations and measurements from radiometers. The approach follows the Guide to the Expression of Uncertainty in Measurement (GUM).« less

The moon as a radiometric reference source for on-orbit sensor stability calibration

USGS Publications Warehouse

Stone, T.C.

2009-01-01

The wealth of data generated by the world's Earth-observing satellites, now spanning decades, allows the construction of long-term climate records. A key consideration for detecting climate trends is precise quantification of temporal changes in sensor calibration on-orbit. For radiometer instruments in the solar reflectance wavelength range (near-UV to shortwave-IR), the Moon can be viewed as a solar diffuser with exceptional stability properties. A model for the lunar spectral irradiance that predicts the geometric variations in the Moon's brightness with ???1% precision has been developed at the U.S. Geological Survey in Flagstaff, AZ. Lunar model results corresponding to a series of Moon observations taken by an instrument can be used to stabilize sensor calibration with sub-percent per year precision, as demonstrated by the Sea-viewing Wide Field-of-view Sensor (SeaWiFS). The inherent stability of the Moon and the operational model to utilize the lunar irradiance quantity provide the Moon as a reference source for monitoring radiometric calibration in orbit. This represents an important capability for detecting terrestrial climate change from space-based radiometric measurements.

RADIOACTIVE DISEQUILIBRIUM AND DYNAMIC OF NATURAL RADIONUCLIDES IN SOILS IN THE STATE OF PERNAMBUCO-BRAZIL.

PubMed

Dos Santos Júnior, José Araújo; Dos Santos Amaral, Romilton; do Nascimento Santos, Josineide Marques; da Silva, Arykerne Nascimento Casado; Rojas, Lino Angel Valcárcel; Milan, Marvic Ortueta; de Almeida Maciel Neto, José; Bezerra, Jairo Dias; Araújo, Eduardo Eudes Nóbrega de

2018-06-15

Environmental radioactivity studies have been allowed establishing radiometric patterns in several area of the earth's crust. The work was conducted through radiometric analyses of regions with high levels of radionuclides and others with no history of anomalies. The research allowed establishing the radiometric profile of soils in the state of Pernambuco, Brazil, using a gamma spectrometry system. The specific activities ranged from 16.5 to 287.5 Bq kg-1 for 238U, 2.0 to 191.7 Bq kg-1 for 226Ra, 1.3 to 281.4 Bq kg-1 for 232Th and from 5.0 to 2600.9 Bq kg-1 for 40K. The results showed areas with low levels of ionizing radiation. However, for 40K some points presented high values, although non-representative of the number of samples investigated. The 226Ra/238U and 232Th/238U ratios allowed to determine the radioactive imbalance condition and to obtain information about aspects of soil availability providing an assessment of the dynamics of these radionuclides.

Particle Transport and Size Sorting in Bubble Microstreaming Flow

NASA Astrophysics Data System (ADS)

Thameem, Raqeeb; Rallabandi, Bhargav; Wang, Cheng; Hilgenfeldt, Sascha

2014-11-01

Ultrasonic driving of sessile semicylindrical bubbles results in powerful steady streaming flows that are robust over a wide range of driving frequencies. In a microchannel, this flow field pattern can be fine-tuned to achieve size-sensitive sorting and trapping of particles at scales much smaller than the bubble itself; the sorting mechanism has been successfully described based on simple geometrical considerations. We investigate the sorting process in more detail, both experimentally (using new parameter variations that allow greater control over the sorting) and theoretically (incorporating the device geometry as well as the superimposed channel flow into an asymptotic theory). This results in optimized criteria for size sorting and a theoretical description that closely matches the particle behavior close to the bubble, the crucial region for size sorting.

Sperm sex-sorting and preservation for managing the sex ratio and genetic diversity of the southern white rhinoceros (Ceratotherium simum simum).

PubMed

O'Brien, J K; Roth, T L; Stoops, M A; Ball, R L; Steinman, K J; Montano, G A; Love, C C; Robeck, T R

2015-01-01

White rhinoceros ejaculates (n=9) collected by electroejaculation from four males were shipped (10°C, 12h) to develop procedures for the production of chilled and frozen-thawed sex-sorted spermatozoa of adequate quality for artificial insemination (AI). Of all electroejaculate fractions, 39.7% (31/78) exhibited high quality post-collection (≥70% total motility and membrane integrity) and of those, 54.8% (17/31) presented reduced in vitro quality after transport and were retrospectively determined to exhibit urine-contamination (≥21.0μg creatinine/ml). Of fractions analyzed for creatinine concentration, 69% (44/64) were classified as urine-contaminated. For high quality non-contaminated fractions, in vitro parameters (motility, velocity, membrane, acrosome and DNA integrity) of chilled non-sorted and sorted spermatozoa were well-maintained at 5°C up to 54h post-collection, whereby >70% of post-transport (non-sorted) or post-sort (sorted) values were retained. By 54h post-collection, some motility parameters were higher (P<0.05) for non-sorted spermatozoa (total motility, rapid velocity, average path velocity) whereas all remaining motion parameters as well as membrane, acrosome and DNA integrity were similar between sperm types. In comparison with a straw method, directional freezing resulted in enhanced (P<0.05) motility and velocity of non-sorted and sorted spermatozoa, with comparable overall post-thaw quality between sperm types. High purity enrichment of X-bearing (89±6%) or Y-bearing (86±3%) spermatozoa was achieved using moderate sorting rates (2540±498X-spermatozoa/s; 1800±557Y-spermatozoa/s). Collective in vitro characteristics of sorted-chilled or sorted-frozen-thawed spermatozoa derived from high quality electroejaculates indicate acceptable fertility potential for use in AI. Copyright © 2014 Elsevier B.V. All rights reserved.

Encapsulation of sex sorted boar semen: sperm membrane status and oocyte penetration parameters.

PubMed

Spinaci, Marcella; Chlapanidas, Theodora; Bucci, Diego; Vallorani, Claudia; Perteghella, Sara; Lucconi, Giulia; Communod, Ricardo; Vigo, Daniele; Galeati, Giovanna; Faustini, Massimo; Torre, Maria Luisa

2013-03-01

Although sorted semen is experimentally used for artificial, intrauterine, and intratubal insemination and in vitro fertilization, its commercial application in swine species is still far from a reality. This is because of the low sort rate and the large number of sperm required for routine artificial insemination in the pig, compared with other production animals, and the greater susceptibility of porcine spermatozoa to stress induced by the different sex sorting steps and the postsorting handling protocols. The encapsulation technology could overcome this limitation in vivo, protecting and allowing the slow release of low-dose sorted semen. The aim of this work was to evaluate the impact of the encapsulation process on viability, acrosome integrity, and on the in vitro fertilizing potential of sorted boar semen. Our results indicate that the encapsulation technique does not damage boar sorted semen; in fact, during a 72-hour storage, no differences were observed between liquid-stored sorted semen and encapsulated sorted semen in terms of plasma membrane (39.98 ± 14.38% vs. 44.32 ± 11.72%, respectively) and acrosome integrity (74.32 ± 12.17% vs. 66.07 ± 10.83%, respectively). Encapsulated sorted spermatozoa presented a lower penetration potential than nonencapsulated ones (47.02% vs. 24.57%, respectively, P < 0.0001), and a significant reduction of polyspermic fertilization (60.76% vs. 36.43%, respectively, polyspermic ova/total ova; P < 0.0001). However, no difference (P > 0.05) was observed in terms of total efficiency of fertilization expressed as normospermic oocytes/total oocytes (18.45% vs. 15.43% for sorted diluted and sorted encapsulated semen, respectively). The encapsulation could be an alternative method of storing of pig sex sorted spermatozoa and is potentially a promising technique in order to optimize the use of low dose of sexed spermatozoa in vivo. Copyright © 2013 Elsevier Inc. All rights reserved.

Sortilin 1 Loss-of-Function Protects Against Cholestatic Liver Injury by Attenuating Hepatic Bile Acid Accumulation in Bile Duct Ligated Mice.

PubMed

Li, Jibiao; Woolbright, Benjamin L; Zhao, Wen; Wang, Yifeng; Matye, David; Hagenbuch, Bruno; Jaeschke, Hartmut; Li, Tiangang

2018-01-01

Sortilin 1 (Sort1) is an intracellular trafficking receptor that mediates protein sorting in the endocytic or secretory pathways. Recent studies revealed a role of Sort1 in the regulation of cholesterol and bile acid (BA) metabolism. This study further investigated the role of Sort1 in modulating BA detoxification and cholestatic liver injury in bile duct ligated mice. We found that Sort1 knockout (KO) mice had attenuated liver injury 24 h after bile duct ligation (BDL), which was mainly attributed to less bile infarct formation. Sham-operated Sort1 KO mice had about 20% larger BA pool size than sham-operated wildtype (WT) mice, but 24 h after BDL Sort1 KO mice had significantly attenuated hepatic BA accumulation and smaller BA pool size. After 14 days BDL, Sort1 KO mice showed significantly lower hepatic BA concentration and reduced expression of inflammatory and fibrotic marker genes, but similar degree of liver fibrosis compared with WT mice. Unbiased quantitative proteomics revealed that Sort1 KO mice had increased hepatic BA sulfotransferase 2A1, but unaltered phase-I BA metabolizing cytochrome P450s or phase-III BA efflux transporters. Consistently, Sort1 KO mice showed elevated plasma sulfated taurocholate after BDL. Finally, we found that liver Sort1 was repressed after BDL, which may be due to BA activation of farnesoid x receptor. In conclusion, we report a role of Sort1 in the regulation of hepatic BA detoxification and cholestatic liver injury in mice. The mechanisms underlying increased hepatic BA elimination in Sort1 KO mice after BDL require further investigation. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Reducing 4D CT artifacts using optimized sorting based on anatomic similarity.

PubMed

Johnston, Eric; Diehn, Maximilian; Murphy, James D; Loo, Billy W; Maxim, Peter G

2011-05-01

Four-dimensional (4D) computed tomography (CT) has been widely used as a tool to characterize respiratory motion in radiotherapy. The two most commonly used 4D CT algorithms sort images by the associated respiratory phase or displacement into a predefined number of bins, and are prone to image artifacts at transitions between bed positions. The purpose of this work is to demonstrate a method of reducing motion artifacts in 4D CT by incorporating anatomic similarity into phase or displacement based sorting protocols. Ten patient datasets were retrospectively sorted using both the displacement and phase based sorting algorithms. Conventional sorting methods allow selection of only the nearest-neighbor image in time or displacement within each bin. In our method, for each bed position either the displacement or the phase defines the center of a bin range about which several candidate images are selected. The two dimensional correlation coefficients between slices bordering the interface between adjacent couch positions are then calculated for all candidate pairings. Two slices have a high correlation if they are anatomically similar. Candidates from each bin are then selected to maximize the slice correlation over the entire data set using the Dijkstra's shortest path algorithm. To assess the reduction of artifacts, two thoracic radiation oncologists independently compared the resorted 4D datasets pairwise with conventionally sorted datasets, blinded to the sorting method, to choose which had the least motion artifacts. Agreement between reviewers was evaluated using the weighted kappa score. Anatomically based image selection resulted in 4D CT datasets with significantly reduced motion artifacts with both displacement (P = 0.0063) and phase sorting (P = 0.00022). There was good agreement between the two reviewers, with complete agreement 34 times and complete disagreement 6 times. Optimized sorting using anatomic similarity significantly reduces 4D CT motion artifacts compared to conventional phase or displacement based sorting. This improved sorting algorithm is a straightforward extension of the two most common 4D CT sorting algorithms.

NIH Toolbox Cognition Battery (NIHTB-CB): list sorting test to measure working memory.

PubMed

Tulsky, David S; Carlozzi, Noelle; Chiaravalloti, Nancy D; Beaumont, Jennifer L; Kisala, Pamela A; Mungas, Dan; Conway, Kevin; Gershon, Richard

2014-07-01

The List Sorting Working Memory Test was designed to assess working memory (WM) as part of the NIH Toolbox Cognition Battery. List Sorting is a sequencing task requiring children and adults to sort and sequence stimuli that are presented visually and auditorily. Validation data are presented for 268 participants ages 20 to 85 years. A subset of participants (N=89) was retested 7 to 21 days later. As expected, the List Sorting Test had moderately high correlations with other measures of working memory and executive functioning (convergent validity) but a low correlation with a test of receptive vocabulary (discriminant validity). Furthermore, List Sorting demonstrates expected changes over the age span and has excellent test-retest reliability. Collectively, these results provide initial support for the construct validity of the List Sorting Working Memory Measure as a measure of working memory. However, the relationship between the List Sorting Test and general executive function has yet to be determined.

Manual sorting to eliminate aflatoxin from peanuts.

PubMed

Galvez, F C F; Francisco, M L D L; Villarino, B J; Lustre, A O; Resurreccion, A V A

2003-10-01

A manual sorting procedure was developed to eliminate aflatoxin contamination from peanuts. The efficiency of the sorting process in eliminating aflatoxin-contaminated kernels from lots of raw peanuts was verified. The blanching of 20 kg of peanuts at 140 degrees C for 25 min in preheated roasters facilitated the manual sorting of aflatoxin-contaminated kernels after deskinning. The manual sorting of raw materials with initially high aflatoxin contents (300 ppb) resulted in aflatoxin-free peanuts (i.e., peanuts in which no aflatoxin was detected). Verification procedures showed that the sorted sound peanuts contained no aflatoxin or contained low levels (<15 ppb) of aflatoxin. The results obtained confirmed that the sorting process was effective in separating contaminated peanuts whether or nor contamination was extensive. At the commercial level, when roasters were not preheated, the dry blanching of 50 kg of peanuts for 45 to 55 min facilitated the proper deskinning and subsequent manual sorting of aflatoxin-contaminated peanut kernels from sound kernels.

Automated spike sorting algorithm based on Laplacian eigenmaps and k-means clustering.

PubMed

Chah, E; Hok, V; Della-Chiesa, A; Miller, J J H; O'Mara, S M; Reilly, R B

2011-02-01

This study presents a new automatic spike sorting method based on feature extraction by Laplacian eigenmaps combined with k-means clustering. The performance of the proposed method was compared against previously reported algorithms such as principal component analysis (PCA) and amplitude-based feature extraction. Two types of classifier (namely k-means and classification expectation-maximization) were incorporated within the spike sorting algorithms, in order to find a suitable classifier for the feature sets. Simulated data sets and in-vivo tetrode multichannel recordings were employed to assess the performance of the spike sorting algorithms. The results show that the proposed algorithm yields significantly improved performance with mean sorting accuracy of 73% and sorting error of 10% compared to PCA which combined with k-means had a sorting accuracy of 58% and sorting error of 10%.A correction was made to this article on 22 February 2011. The spacing of the title was amended on the abstract page. No changes were made to the article PDF and the print version was unaffected.

A Simple Deep Learning Method for Neuronal Spike Sorting

NASA Astrophysics Data System (ADS)

Yang, Kai; Wu, Haifeng; Zeng, Yu

2017-10-01

Spike sorting is one of key technique to understand brain activity. With the development of modern electrophysiology technology, some recent multi-electrode technologies have been able to record the activity of thousands of neuronal spikes simultaneously. The spike sorting in this case will increase the computational complexity of conventional sorting algorithms. In this paper, we will focus spike sorting on how to reduce the complexity, and introduce a deep learning algorithm, principal component analysis network (PCANet) to spike sorting. The introduced method starts from a conventional model and establish a Toeplitz matrix. Through the column vectors in the matrix, we trains a PCANet, where some eigenvalue vectors of spikes could be extracted. Finally, support vector machine (SVM) is used to sort spikes. In experiments, we choose two groups of simulated data from public databases availably and compare this introduced method with conventional methods. The results indicate that the introduced method indeed has lower complexity with the same sorting errors as the conventional methods.

NIH Toolbox Cognition Battery (NIHTB-CB): The List Sorting Test to Measure Working Memory

PubMed Central

Tulsky, David S.; Carlozzi, Noelle; Chiaravalloti, Nancy D.; Beaumont, Jennifer L.; Kisala, Pamela A.; Mungas, Dan; Conway, Kevin; Gershon, Richard

2015-01-01

The List Sorting Working Memory Test was designed to assess working memory (WM) as part of the NIH Toolbox Cognition Battery. List Sorting is a sequencing task requiring children and adults to sort and sequence stimuli that are presented visually and auditorily. Validation data are presented for 268 participants ages 20 to 85 years. A subset of participants (N=89) was retested 7 to 21 days later. As expected, the List Sorting Test had moderately high correlations with other measures of working memory and executive functioning (convergent validity) but a low correlation with a test of receptive vocabulary (discriminant validity). Furthermore, List Sorting demonstrates expected changes over the age span and has excellent test-retest reliability. Collectively, these results provide initial support the construct validity of the List Sorting Working Memory Measure as a measure of working memory. However, the relation between the List Sorting Test and general executive function has yet to be determined. PMID:24959983

Regulation of synaptic activity by snapin-mediated endolysosomal transport and sorting

PubMed Central

Di Giovanni, Jerome; Sheng, Zu-Hang

2015-01-01

Recycling synaptic vesicles (SVs) transit through early endosomal sorting stations, which raises a fundamental question: are SVs sorted toward endolysosomal pathways? Here, we used snapin mutants as tools to assess how endolysosomal sorting and trafficking impact presynaptic activity in wild-type and snapin−/− neurons. Snapin acts as a dynein adaptor that mediates the retrograde transport of late endosomes (LEs) and interacts with dysbindin, a subunit of the endosomal sorting complex BLOC-1. Expressing dynein-binding defective snapin mutants induced SV accumulation at presynaptic terminals, mimicking the snapin−/− phenotype. Conversely, over-expressing snapin reduced SV pool size by enhancing SV trafficking to the endolysosomal pathway. Using a SV-targeted Ca2+ sensor, we demonstrate that snapin–dysbindin interaction regulates SV positional priming through BLOC-1/AP-3-dependent sorting. Our study reveals a bipartite regulation of presynaptic activity by endolysosomal trafficking and sorting: LE transport regulates SV pool size, and BLOC-1/AP-3-dependent sorting fine-tunes the Ca2+ sensitivity of SV release. Therefore, our study provides new mechanistic insights into the maintenance and regulation of SV pool size and synchronized SV fusion through snapin-mediated LE trafficking and endosomal sorting. PMID:26108535

Radiometric liquid level gauge with linear-detection (in German)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glaeser, M.; Emmelmann, K.P.

1973-09-01

A description is given of a radiometric liquid level gauge with linear detection. It consists of a set of radioactive sources (e.g., /sup 137/Cs) with quadratic graduation in their activities, of a scintillation counter with electronic back-up unit and of a slender tube. The tube, sources and scintillation counter form a compact snd easily transportsble liquid level gauge. It is-especially adapted for liquid level measurements in slender, difficulty accessible and opaque containers. The device supplements the different methods for liquid level measurement with a new variant which is adopted for many cases in practice. (auth)

Machine processing of ERTS and ground truth data

NASA Technical Reports Server (NTRS)

Rogers, R. H. (Principal Investigator); Peacock, K.

1973-01-01

The author has identified the following significant results. Results achieved by ERTS-Atmospheric Experiment PR303, whose objective is to establish a radiometric calibration technique, are reported. This technique, which determines and removes solar and atmospheric parameters that degrade the radiometric fidelity of ERTS-1 data, transforms the ERTS-1 sensor radiance measurements to absolute target reflectance signatures. A radiant power measuring instrument and its use in determining atmospheric parameters needed for ground truth are discussed. The procedures used and results achieved in machine processing ERTS-1 computer -compatible tapes and atmospheric parameters to obtain target reflectance are reviewed.

Radiometric calibration of Landsat Thematic Mapper multispectral images

USGS Publications Warehouse

Chavez, P.S.

1989-01-01

A main problem encountered in radiometric calibration of satellite image data is correcting for atmospheric effects. Without this correction, an image digital number (DN) cannot be converted to a surface reflectance value. In this paper the accuracy of a calibration procedure, which includes a correction for atmospheric scattering, is tested. Two simple methods, a stand-alone and an in situ sky radiance measurement technique, were used to derive the HAZE DN values for each of the six reflectance Thematic Mapper (TM) bands. The DNs of two Landsat TM images of Phoenix, Arizona were converted to surface reflectances. -from Author

LANDSAT-4 band 6 data evaluation

NASA Technical Reports Server (NTRS)

1983-01-01

The radiometric integrity of the LANDSAT-D thematic mapper (TM) thermal infrared channel (band 6) data was evaluated to develop improved radiometric preprocessing calibration techniques for removal of atmospheric effects. Primary data analysis was spent in evaluating the line to line and detector to detector variation in the thermal infrared data. The data studied was in the core area of Lake Ontario where very stable temperatures were expected. The detectors and the scan direction were taken as separate parameters and an analysis of variance was conducted. The data indicate that significant variability exists both between detectors and between scan directions.

Radiometers Optimize Local Weather Prediction

NASA Technical Reports Server (NTRS)

2010-01-01

Radiometrics Corporation, headquartered in Boulder, Colorado, engaged in Small Business Innovation Research (SBIR) agreements with Glenn Research Center that resulted in a pencil-beam radiometer designed to detect supercooled liquid along flight paths -- a prime indicator of dangerous icing conditions. The company has brought to market a modular radiometer that resulted from the SBIR work. Radiometrics' radiometers are used around the world as key tools for detecting icing conditions near airports and for the prediction of weather conditions like fog and convective storms, which are known to produce hail, strong winds, flash floods, and tornadoes. They are also employed for oceanographic research and soil moisture studies.

Analysis of radiometric signal in sedimentating suspension flow in open channel

NASA Astrophysics Data System (ADS)

Zych, Marcin; Hanus, Robert; Petryka, Leszek; Świsulski, Dariusz; Doktor, Marek; Mastej, Wojciech

2015-05-01

The article discusses issues related to the estimation of the sedimentating solid particles average flow velocity in an open channel using radiometric methods. Due to the composition of the compound, which formed water and diatomite, received data have a very weak signal to noise ratio. In the process analysis the known determining of the solid phase transportation time delay the classical cross-correlation function is the most reliable method. The use of advanced frequency analysis based on mutual spectral density function and wavelet transform of recorded signals allows a reduction of the noise contribution.

Spectrally and Radiometrically Stable, Wideband, Onboard Calibration Source

NASA Technical Reports Server (NTRS)

Coles, James B.; Richardson, Brandon S.; Eastwood, Michael L.; Sarture, Charles M.; Quetin, Gregory R.; Porter, Michael D.; Green, Robert O.; Nolte, Scott H.; Hernandez, Marco A.; Knoll, Linley A.

2013-01-01

The Onboard Calibration (OBC) source incorporates a medical/scientific-grade halogen source with a precisely designed fiber coupling system, and a fiber-based intensity-monitoring feedback loop that results in radiometric and spectral stabilities to within less than 0.3 percent over a 15-hour period. The airborne imaging spectrometer systems developed at the Jet Propulsion Laboratory incorporate OBC sources to provide auxiliary in-use system calibration data. The use of the OBC source will provide a significant increase in the quantitative accuracy, reliability, and resulting utility of the spectral data collected from current and future imaging spectrometer instruments.

Evaluation of spatial, radiometric and spectral Thematic Mapper performance for coastal studies

NASA Technical Reports Server (NTRS)

Klemas, V.; Ackleson, S. G.; Hardisky, M. A.

1985-01-01

On 31 March 1983, the University of Delaware's Center for Remote Sensing initiated a study to evaluate the spatial, radiometric and spectral performance of the LANDSAT Thematic Mapper for coastal and estuarine studies. The investigation was supported by Contract NAS5-27580 from the NASA Goddard Space Flight Center. The research was divided into three major subprojects: (1) a comparison of LANDSAT TM to MSS imagery for detecting submerged aquatic vegetation in Chesapeake Bay; (2) remote sensing of submerged aquatic vegetation - a radiative transfer approach; and (3) remote sensing of coastal wetland biomass using Thematic Mapper wavebands.

Cropland measurement using Thematic Mapper data and radiometric model

NASA Technical Reports Server (NTRS)

Lyon, John G.; Khuwaiter, I. H. S.

1989-01-01

To halt erosion and desertification, it is necessary to quantify resources that are affected. Necessary information includes inventory of croplands and desert areas as they change over time. Several studies indicate the value of remote sensor data as input to inventories. In this study, the radiometric modeling of spectral characteristics of soil and vegetation provides the theoretical basis for the remote sensing approach. Use of Landsat Thematic Mapper images allows measurement of croplands in Saudi Arabia, demonstrating the capability of the approach. The inventory techniques and remote sensing approach presented are potentially useful in developing countries.

Airborne interferometer for atmospheric emission and solar absorption.

PubMed

Keith, D W; Dykema, J A; Hu, H; Lapson, L; Anderson, J G

2001-10-20

The interferometer for emission and solar absorption (INTESA) is an infrared spectrometer designed to study radiative transfer in the troposphere and lower stratosphere from a NASA ER-2 aircraft. The Fourier-transform spectrometer (FTS) operates from 0.7 to 50 mum with a resolution of 0.7 cm(-1). The FTS observes atmospheric thermal emission from multiple angles above and below the aircraft. A heliostat permits measurement of solar absorption spectra. INTESA's calibration system includes three blackbodies to permit in-flight assessment of radiometric error. Results suggest that the in-flight radiometric accuracy is ~0.5 K in the mid-infrared.

Titan Density Reconstruction Using Radiometric and Cassini Attitude Control Flight Data

NASA Technical Reports Server (NTRS)

Andrade, Luis G., Jr.; Burk, Thomas A.

2015-01-01

This paper compares three different methods of Titan atmospheric density reconstruction for the Titan 87 Cassini flyby. T87 was a unique flyby that provided independent Doppler radiometric measurements on the ground throughout the flyby including at Titan closest approach. At the same time, the onboard accelerometer provided an independent estimate of atmospheric drag force and density during the flyby. These results are compared with the normal method of reconstructing atmospheric density using thruster on-time and angular momentum accumulation. Differences between the estimates are analyzed and a possible explanation for the differences is evaluated.

A simple and effective radiometric correction method to improve landscape change detection across sensors and across time

USGS Publications Warehouse

Chen, X.; Vierling, Lee; Deering, D.

2005-01-01

Satellite data offer unrivaled utility in monitoring and quantifying large scale land cover change over time. Radiometric consistency among collocated multi-temporal imagery is difficult to maintain, however, due to variations in sensor characteristics, atmospheric conditions, solar angle, and sensor view angle that can obscure surface change detection. To detect accurate landscape change using multi-temporal images, we developed a variation of the pseudoinvariant feature (PIF) normalization scheme: the temporally invariant cluster (TIC) method. Image data were acquired on June 9, 1990 (Landsat 4), June 20, 2000 (Landsat 7), and August 26, 2001 (Landsat 7) to analyze boreal forests near the Siberian city of Krasnoyarsk using the normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), and reduced simple ratio (RSR). The temporally invariant cluster (TIC) centers were identified via a point density map of collocated pixel VIs from the base image and the target image, and a normalization regression line was created to intersect all TIC centers. Target image VI values were then recalculated using the regression function so that these two images could be compared using the resulting common radiometric scale. We found that EVI was very indicative of vegetation structure because of its sensitivity to shadowing effects and could thus be used to separate conifer forests from deciduous forests and grass/crop lands. Conversely, because NDVI reduced the radiometric influence of shadow, it did not allow for distinctions among these vegetation types. After normalization, correlations of NDVI and EVI with forest leaf area index (LAI) field measurements combined for 2000 and 2001 were significantly improved; the r 2 values in these regressions rose from 0.49 to 0.69 and from 0.46 to 0.61, respectively. An EVI "cancellation effect" where EVI was positively related to understory greenness but negatively related to forest canopy coverage was evident across a post fire chronosequence with normalized data. These findings indicate that the TIC method provides a simple, effective and repeatable method to create radiometrically comparable data sets for remote detection of landscape change. Compared to some previous relative radiometric normalization methods, this new method does not require high level programming and statistical skills, yet remains sensitive to landscape changes occurring over seasonal and inter-annual time scales. In addition, the TIC method maintains sensitivity to subtle changes in vegetation phenology and enables normalization even when invariant features are rare. While this normalization method allowed detection of a range of land use, land cover, and phenological/biophysical changes in the Siberian boreal forest region studied here, it is necessary to further examine images representing a wide variety of ecoregions to thoroughly evaluate the TIC method against other normalization schemes. ?? 2005 Elsevier Inc. All rights reserved.

CellSort: a support vector machine tool for optimizing fluorescence-activated cell sorting and reducing experimental effort.

PubMed

Yu, Jessica S; Pertusi, Dante A; Adeniran, Adebola V; Tyo, Keith E J

2017-03-15

High throughput screening by fluorescence activated cell sorting (FACS) is a common task in protein engineering and directed evolution. It can also be a rate-limiting step if high false positive or negative rates necessitate multiple rounds of enrichment. Current FACS software requires the user to define sorting gates by intuition and is practically limited to two dimensions. In cases when multiple rounds of enrichment are required, the software cannot forecast the enrichment effort required. We have developed CellSort, a support vector machine (SVM) algorithm that identifies optimal sorting gates based on machine learning using positive and negative control populations. CellSort can take advantage of more than two dimensions to enhance the ability to distinguish between populations. We also present a Bayesian approach to predict the number of sorting rounds required to enrich a population from a given library size. This Bayesian approach allowed us to determine strategies for biasing the sorting gates in order to reduce the required number of enrichment rounds. This algorithm should be generally useful for improve sorting outcomes and reducing effort when using FACS. Source code available at http://tyolab.northwestern.edu/tools/ . k-tyo@northwestern.edu. Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

Categorizing Variations of Student-Implemented Sorting Algorithms

ERIC Educational Resources Information Center

Taherkhani, Ahmad; Korhonen, Ari; Malmi, Lauri

2012-01-01

In this study, we examined freshmen students' sorting algorithm implementations in data structures and algorithms' course in two phases: at the beginning of the course before the students received any instruction on sorting algorithms, and after taking a lecture on sorting algorithms. The analysis revealed that many students have insufficient…

Review of log sort yards

Treesearch

John Rusty Dramm; Gerry L. Jackson; Jenny Wong

2002-01-01

This report provides a general overview of current log sort yard operations in the United States, including an extensive literature review and information collected during on-site visits to several operations throughout the nation. Log sort yards provide many services in marketing wood and fiber by concentrating, merchandising, processing, sorting, and adding value to...

COST EVALUATION OF AUTOMATED AND MANUAL POST- CONSUMER PLASTIC BOTTLE SORTING SYSTEMS

EPA Science Inventory

This project evaluates, on the basis of performance and cost, two Automated BottleSort® sorting systems for post-consumer commingled plastic containers developed by Magnetic Separation Systems. This study compares the costs to sort mixed bales of post-consumer plastic at these t...

An accelerated image matching technique for UAV orthoimage registration

NASA Astrophysics Data System (ADS)

Tsai, Chung-Hsien; Lin, Yu-Ching

2017-06-01

Using an Unmanned Aerial Vehicle (UAV) drone with an attached non-metric camera has become a popular low-cost approach for collecting geospatial data. A well-georeferenced orthoimage is a fundamental product for geomatics professionals. To achieve high positioning accuracy of orthoimages, precise sensor position and orientation data, or a number of ground control points (GCPs), are often required. Alternatively, image registration is a solution for improving the accuracy of a UAV orthoimage, as long as a historical reference image is available. This study proposes a registration scheme, including an Accelerated Binary Robust Invariant Scalable Keypoints (ABRISK) algorithm and spatial analysis of corresponding control points for image registration. To determine a match between two input images, feature descriptors from one image are compared with those from another image. A "Sorting Ring" is used to filter out uncorrected feature pairs as early as possible in the stage of matching feature points, to speed up the matching process. The results demonstrate that the proposed ABRISK approach outperforms the vector-based Scale Invariant Feature Transform (SIFT) approach where radiometric variations exist. ABRISK is 19.2 times and 312 times faster than SIFT for image sizes of 1000 × 1000 pixels and 4000 × 4000 pixels, respectively. ABRISK is 4.7 times faster than Binary Robust Invariant Scalable Keypoints (BRISK). Furthermore, the positional accuracy of the UAV orthoimage after applying the proposed image registration scheme is improved by an average of root mean square error (RMSE) of 2.58 m for six test orthoimages whose spatial resolutions vary from 6.7 cm to 10.7 cm.

DOE Office of Scientific and Technical Information (OSTI.GOV)

May, R.T.; Strand, J.R.; Reid, B.E.

Uranium favorability of the Sangre de Cristo Formation (Pennsylvanian-Permian) in the Las Vegas basin has been evaluated. The Las Vegas basin project area, located in Colfax, Mora, and San Miguel Counties, New Mexico, comprises about 3,489 sq mi. The formation contains sedimentologic and stratigraphic characteristics that are considered favorable for uranium deposition. Field investigations consisted of section measuring, rock sampling, and ground radiometric reconnaissance. North-south and east-west cross sections of the basin were prepared from well logs and measured sections. Petrographic, chemical, and spectrographic analyses were conducted on selected samples. Stratigraphic and sedimentologic information were used to determine depositional environments.more » The most favorable potential host rocks include red to pink, coarse-grained, poorly sorted, feldspathic to arkosic lenticular sandstones with stacked sandstone thicknesses of more than 20 ft and sandstone-to-shale ratios between 1:1 and 2:1. The sandstone is interbedded with mudstone and contains carbonaceous debris and anomalous concentrations of uranium locally. Areas of maximum favorability are found in a braided-stream, alluvial-plain depositional environment in the north-central part of the Las Vegas basin. There, carbonaceous material is well preserved, probably due to rapid subsidence and burial. Furthermore, uranium favorability is highest in the lower half of the formation because carbonaceous wood and plant fragments, as well as known uranium deposits, are concentrated in this zone. Piedmont deposits in the north and east, and meander-belt, alluvial-plain deposits in the south, are not considered favorable because of the paucity of uranium deposits and a minimum of carbonaceous material.« less

Suitability of low cost commercial off-the-shelf aerial platforms and consumer grade digital cameras for small format aerial photography

NASA Astrophysics Data System (ADS)

Turley, Anthony Allen

Many research projects require the use of aerial images. Wetlands evaluation, crop monitoring, wildfire management, environmental change detection, and forest inventory are but a few of the applications of aerial imagery. Low altitude Small Format Aerial Photography (SFAP) is a bridge between satellite and man-carrying aircraft image acquisition and ground-based photography. The author's project evaluates digital images acquired using low cost commercial digital cameras and standard model airplanes to determine their suitability for remote sensing applications. Images from two different sites were obtained. Several photo missions were flown over each site, acquiring images in the visible and near infrared electromagnetic bands. Images were sorted and analyzed to select those with the least distortion, and blended together with Microsoft Image Composite Editor. By selecting images taken within minutes apart, radiometric qualities of the images were virtually identical, yielding no blend lines in the composites. A commercial image stitching program, Autopano Pro, was purchased during the later stages of this study. Autopano Pro was often able to mosaic photos that the free Image Composite Editor was unable to combine. Using telemetry data from an onboard data logger, images were evaluated to calculate scale and spatial resolution. ERDAS ER Mapper and ESRI ArcGIS were used to rectify composite images. Despite the limitations inherent in consumer grade equipment, images of high spatial resolution were obtained. Mosaics of as many as 38 images were created, and the author was able to record detailed aerial images of forest and wetland areas where foot travel was impractical or impossible.

Application of visible spectroscopy in waste sorting

NASA Astrophysics Data System (ADS)

Spiga, Philippe; Bourely, Antoine

2011-10-01

Today, waste recycling, (bottles, papers...), is a mechanical operation: the waste are crushed, fused and agglomerated in order to obtain new manufactured products (e.g. new bottles, clothes ...). The plastics recycling is the main application in the color sorting process. The colorless plastics recovered are more valuable than the colored plastics. Other emergent applications are in the paper sorting, where the main goal is to sort dyed paper from white papers. Up to now, Pellenc Selective Technologies has manufactured color sorting machines based on RGB cameras. Three dimensions (red, green and blue) are no longer sufficient to detect low quantities of dye in the considered waste. In order to increase the efficiency of the color detection, a new sorting machine, based on visible spectroscopy, has been developed. This paper presents the principles of the two approaches and their difference in terms of sorting performance, making visible spectroscopy a clear winner.

MetaSort untangles metagenome assembly by reducing microbial community complexity

PubMed Central

Ji, Peifeng; Zhang, Yanming; Wang, Jinfeng; Zhao, Fangqing

2017-01-01

Most current approaches to analyse metagenomic data rely on reference genomes. Novel microbial communities extend far beyond the coverage of reference databases and de novo metagenome assembly from complex microbial communities remains a great challenge. Here we present a novel experimental and bioinformatic framework, metaSort, for effective construction of bacterial genomes from metagenomic samples. MetaSort provides a sorted mini-metagenome approach based on flow cytometry and single-cell sequencing methodologies, and employs new computational algorithms to efficiently recover high-quality genomes from the sorted mini-metagenome by the complementary of the original metagenome. Through extensive evaluations, we demonstrated that metaSort has an excellent and unbiased performance on genome recovery and assembly. Furthermore, we applied metaSort to an unexplored microflora colonized on the surface of marine kelp and successfully recovered 75 high-quality genomes at one time. This approach will greatly improve access to microbial genomes from complex or novel communities. PMID:28112173

Ubiquitin-dependent sorting of integral membrane proteins for degradation in lysosomes

PubMed Central

Piper, Robert C.

2007-01-01

Summary The pathways that deliver newly synthesized proteins that reside in lysosomes are well understood by comparison with our knowledge of how integral membrane proteins are sorted and delivered to the lysosome for degradation. Many membrane proteins are sorted to lysosomes following ubiquitination, which provides a sorting signal that can operate for sorting at the TGN (trans-Golgi network), at the plasma membrane or at the endosome for delivery into lumenal vesicles. Candidate multicomponent machines that can potentially move ubiquitinated integral membrane cargo proteins have been identified, but much work is still required to ascertain which of these candidates directly recognizes ubiquitinated cargo and what they do with cargo after recognition. In the case of the machinery required for sorting into the lumenal vesicles of endosomes, other functions have also been determined including a link between sorting and movement of endosomes along microtubules. PMID:17689064

Is it time to revisit the log-sort yard?

Treesearch

John Dramm; Gerry Jackson

2000-01-01

Log-sort yards provide better utilization and marketing with improved value recovery of currently available timber resources in North America. Log-sort yards provide many services in marketing wood and fiber by concentrating, merchandising, manufacturing, sorting, and adding value to logs. Such operations supply forest products firms with desired raw materials, which...

Word Sorts for General Music Classes

ERIC Educational Resources Information Center

Cardany, Audrey Berger

2015-01-01

Word sorts are standard practice for aiding children in acquiring skills in English language arts. When included in the general music classroom, word sorts may aid students in acquiring a working knowledge of music vocabulary. The author shares a word sort activity drawn from vocabulary in John Lithgow's children's book "Never Play…

A new radiometric unit of measure to characterize SWIR illumination

NASA Astrophysics Data System (ADS)

Richards, A.; Hübner, M.

2017-05-01

We propose a new radiometric unit of measure we call the `swux' to unambiguously characterize scene illumination in the SWIR spectral band between 0.8μm-1.8μm, where most of the ever-increasing numbers of deployed SWIR cameras (based on standard InGaAs focal plane arrays) are sensitive. Both military and surveillance applications in the SWIR currently suffer from a lack of a standardized SWIR radiometric unit of measure that can be used to definitively compare or predict SWIR camera performance with respect to SNR and range metrics. We propose a unit comparable to the photometric illuminance lux unit; see Ref. [1]. The lack of a SWIR radiometric unit becomes even more critical if one uses lux levels to describe SWIR sensor performance at twilight or even low light condition, since in clear, no-moon conditions in rural areas, the naturally-occurring SWIR radiation from nightglow produces a much higher irradiance than visible starlight. Thus, even well-intentioned efforts to characterize a test site's ambient illumination levels in the SWIR band may fail based on photometric instruments that only measure visible light. A study of this by one of the authors in Ref. [2] showed that the correspondence between lux values and total SWIR irradiance in typical illumination conditions can vary by more than two orders of magnitude, depending on the spectrum of the ambient background. In analogy to the photometric lux definition, we propose the SWIR irradiance equivalent `swux' level, derived by integration over the scene SWIR spectral irradiance weighted by a spectral sensitivity function S(λ), a SWIR analog of the V(λ) photopic response function.

Spatial and radiometric characterization of multi-spectrum satellite images through multi-fractal analysis

NASA Astrophysics Data System (ADS)

Alonso, Carmelo; Tarquis, Ana M.; Zúñiga, Ignacio; Benito, Rosa M.

2017-03-01

Several studies have shown that vegetation indexes can be used to estimate root zone soil moisture. Earth surface images, obtained by high-resolution satellites, presently give a lot of information on these indexes, based on the data of several wavelengths. Because of the potential capacity for systematic observations at various scales, remote sensing technology extends the possible data archives from the present time to several decades back. Because of this advantage, enormous efforts have been made by researchers and application specialists to delineate vegetation indexes from local scale to global scale by applying remote sensing imagery. In this work, four band images have been considered, which are involved in these vegetation indexes, and were taken by satellites Ikonos-2 and Landsat-7 of the same geographic location, to study the effect of both spatial (pixel size) and radiometric (number of bits coding the image) resolution on these wavelength bands as well as two vegetation indexes: the Normalized Difference Vegetation Index (NDVI) and the Enhanced Vegetation Index (EVI). In order to do so, a multi-fractal analysis of these multi-spectral images was applied in each of these bands and the two indexes derived. The results showed that spatial resolution has a similar scaling effect in the four bands, but radiometric resolution has a larger influence in blue and green bands than in red and near-infrared bands. The NDVI showed a higher sensitivity to the radiometric resolution than EVI. Both were equally affected by the spatial resolution. From both factors, the spatial resolution has a major impact in the multi-fractal spectrum for all the bands and the vegetation indexes. This information should be taken in to account when vegetation indexes based on different satellite sensors are obtained.

Radiometric sounding system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whiteman, C.D.; Anderson, G.A.; Alzheimer, J.M.

1995-04-01

Vertical profiles of solar and terrestrial radiative fluxes are key research needs for global climate change research. These fluxes are expected to change as radiatively active trace gases are emitted to the earth`s atmosphere as a consequence of energy production and industrial and other human activities. Models suggest that changes in the concentration of such gases will lead to radiative flux divergences that will produce global warming of the earth`s atmosphere. Direct measurements of the vertical variation of solar and terrestrial radiative fluxes that lead to these flux divergences have been largely unavailable because of the expense of making suchmore » measurements from airplanes. These measurements are needed to improve existing atmospheric radiative transfer models, especially under the cloudy conditions where the models have not been adequately tested. A tethered-balloon-borne Radiometric Sounding System has been developed at Pacific Northwest Laboratory to provide an inexpensive means of making routine vertical soundings of radiative fluxes in the earth`s atmospheric boundary layer to altitudes up to 1500 m above ground level. Such vertical soundings would supplement measurements being made from aircraft and towers. The key technical challenge in the design of the Radiometric Sounding System is to develop a means of keeping the radiometers horizontal while the balloon ascends and descends in a turbulent atmospheric environment. This problem has been addressed by stabilizing a triangular radiometer-carrying platform that is carried on the tetherline of a balloon sounding system. The platform, carried 30 m or more below the balloon to reduce the balloon`s effect on the radiometric measurements, is leveled by two automatic control loops that activate motors, gears and pulleys when the platform is off-level. The sensitivity of the automatic control loops to oscillatory motions of various frequencies and amplitudes can be adjusted using filters.« less

Design and optimization of an ultra wideband and compact microwave antenna for radiometric monitoring of brain temperature.

PubMed

Rodrigues, Dario B; Maccarini, Paolo F; Salahi, Sara; Oliveira, Tiago R; Pereira, Pedro J S; Limao-Vieira, Paulo; Snow, Brent W; Reudink, Doug; Stauffer, Paul R

2014-07-01

We present the modeling efforts on antenna design and frequency selection to monitor brain temperature during prolonged surgery using noninvasive microwave radiometry. A tapered log-spiral antenna design is chosen for its wideband characteristics that allow higher power collection from deep brain. Parametric analysis with the software HFSS is used to optimize antenna performance for deep brain temperature sensing. Radiometric antenna efficiency (η) is evaluated in terms of the ratio of power collected from brain to total power received by the antenna. Anatomical information extracted from several adult computed tomography scans is used to establish design parameters for constructing an accurate layered 3-D tissue phantom. This head phantom includes separate brain and scalp regions, with tissue equivalent liquids circulating at independent temperatures on either side of an intact skull. The optimized frequency band is 1.1-1.6 GHz producing an average antenna efficiency of 50.3% from a two turn log-spiral antenna. The entire sensor package is contained in a lightweight and low-profile 2.8 cm diameter by 1.5 cm high assembly that can be held in place over the skin with an electromagnetic interference shielding adhesive patch. The calculated radiometric equivalent brain temperature tracks within 0.4 °C of the measured brain phantom temperature when the brain phantom is lowered 10 °C and then returned to the original temperature (37 °C) over a 4.6-h experiment. The numerical and experimental results demonstrate that the optimized 2.5-cm log-spiral antenna is well suited for the noninvasive radiometric sensing of deep brain temperature.

Imaging Spectroscopy Enables Novel Applications and Continuity with the Landsat Record to Sustain Legacy Applications: An Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and Landsat 8 OLI Case Study

NASA Astrophysics Data System (ADS)

Stavros, E. N.; Seidel, F.; Cable, M. L.; Green, R. O.; Freeman, A.

2017-12-01

While, imaging spectrometers offer additional information that provide value added products for applications that are otherwise underserved, there is need to demonstrate their ability to augment the multi-spectral (e.g., Landsat) optical record by both providing more frequent temporal revisit and lengthening the existing record. Here we test the hypothesis that imaging spectroscopic optical data is compatible with multi-spectral data to within ±5% radiometric accuracy, as desirable to continue the long-term Landsat data record. We use a coincident Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) flight with over-passing Operational Land Imager (OLI) data on Landsat 8 to document a procedure for simulating OLI multi-spectral bands from AVIRIS, evaluate influencing factors on the observed radiance, and assess AVIRIS radiometric accuracy compared to OLI. The procedure for simulating OLI data includes spectral convolution, accounting for atmospheric effects introduced by different sensor altitude and viewing geometries, and spatial resampling. After accounting for these influences, we expect the remaining differences between the simulated and the real OLI data result from differences in sensor calibration, surface bi-directional reflectance, from the different viewing geometries, and spatial sampling. The median radiometric percent difference for each band in the data used range from 0.6% to 8.3%. After bias-correction to minimize potential calibration discrepancies, we find no more than 1.2% radiometric percent difference for any OLI band. This analysis therefore successfully demonstrates that imaging spectrometer data can not only address novel applications, but also contribute to the Landsat-type or other multi-spectral data records to sustain legacy applications.

A novel solution for car traffic control based on radiometric microwave devices

NASA Astrophysics Data System (ADS)

Soldovieri, Francesco; Denisov, Alexander; Speziale, Victor

2014-05-01

The significant problem of traffic in big cities, connected with huge and building up quantity of automobile cars, demands for novel strategies, based on nonconventional solutions, in order to improve system traffic control, especially at crossroads. As well known, the usual solution is based on the time relay, which requires the installation of a fixed traffic interval (signal light switching) at a crossroad; this solution is low cost, but does not account for the actual traffic conditions. Therefore, in the recent years, attention is towards to new designs, where the monitoring of the and control of traffic is carried out by using various methods including, optical, the infrared, magnetic, radar tracking, acoustical ones. In this work, we discuss the deployment of high sensitivity radiometric systems and radiometers(sensor) in the microwave range [1, 2]. In fact, the radiometer as "sensor" can provide an always updated information about the car traffic in any weather condition and in absence or low visibility conditions. In fact, the radiometric sensor detects the cars thanks to the different behavior of the car roofs which reflect the cold sky whereas the road asphalt is visible as warm object (at around outside temperature). [1] A. G. Denisov, V. P. Gorishnyak, S. E. Kuzmin et al., "Some experiments concerning resolution of 32 sensors passive 8mm wave imaging system," in Proceedings of the International Symposium on Space Terahertz Technology (ISSTT '09), Charlottesville, Va, USA, April 2009. [2] F. Soldovieri, A. Natale, V. Gorishnyak, A. Pavluchenko, A. Denisov, and L. Chen, "Radiometric Imaging for Monitoring and Surveillance Issues," International Journal of Antennas and Propagation, vol. 2013, Article ID 272561, 8 pages, 2013. doi:10.1155/2013/272561.

Absolute Radiometric Calibration of KOMPSAT-3A

NASA Astrophysics Data System (ADS)

Ahn, H. Y.; Shin, D. Y.; Kim, J. S.; Seo, D. C.; Choi, C. U.

2016-06-01

This paper presents a vicarious radiometric calibration of the Korea Multi-Purpose Satellite-3A (KOMPSAT-3A) performed by the Korea Aerospace Research Institute (KARI) and the Pukyong National University Remote Sensing Group (PKNU RSG) in 2015.The primary stages of this study are summarized as follows: (1) A field campaign to determine radiometric calibrated target fields was undertaken in Mongolia and South Korea. Surface reflectance data obtained in the campaign were input to a radiative transfer code that predicted at-sensor radiance. Through this process, equations and parameters were derived for the KOMPSAT-3A sensor to enable the conversion of calibrated DN to physical units, such as at-sensor radiance or TOA reflectance. (2) To validate the absolute calibration coefficients for the KOMPSAT-3A sensor, we performed a radiometric validation with a comparison of KOMPSAT-3A and Landsat-8 TOA reflectance using one of the six PICS (Libya 4). Correlations between top-of-atmosphere (TOA) radiances and the spectral band responses of the KOMPSAT-3A sensors at the Zuunmod, Mongolia and Goheung, South Korea sites were significant for multispectral bands. The average difference in TOA reflectance between KOMPSAT-3A and Landsat-8 image over the Libya 4, Libya site in the red-green-blue (RGB) region was under 3%, whereas in the NIR band, the TOA reflectance of KOMPSAT-3A was lower than the that of Landsat-8 due to the difference in the band passes of two sensors. The KOMPSAT-3Aensor includes a band pass near 940 nm that can be strongly absorbed by water vapor and therefore displayed low reflectance. Toovercome this, we need to undertake a detailed analysis using rescale methods, such as the spectral bandwidth adjustment factor.

L5 TM radiometric recalibration procedure using the internal calibration trends from the NLAPS trending database

USGS Publications Warehouse

Chander, G.; Haque, Md. O.; Micijevic, E.; Barsi, J.A.

2008-01-01

From the Landsat program's inception in 1972 to the present, the earth science user community has benefited from a historical record of remotely sensed data. The multispectral data from the Landsat 5 (L5) Thematic Mapper (TM) sensor provide the backbone for this extensive archive. Historically, the radiometric calibration procedure for this imagery used the instrument's response to the Internal Calibrator (IC) on a scene-by-scene basis to determine the gain and offset for each detector. The IC system degraded with time causing radiometric calibration errors up to 20 percent. In May 2003 the National Landsat Archive Production System (NLAPS) was updated to use a gain model rather than the scene acquisition specific IC gains to calibrate TM data processed in the United States. Further modification of the gain model was performed in 2007. L5 TM data that were processed using IC prior to the calibration update do not benefit from the recent calibration revisions. A procedure has been developed to give users the ability to recalibrate their existing Level-1 products. The best recalibration results are obtained if the work order report that was originally included in the standard data product delivery is available. However, many users may not have the original work order report. In such cases, the IC gain look-up table that was generated using the radiometric gain trends recorded in the NLAPS database can be used for recalibration. This paper discusses the procedure to recalibrate L5 TM data when the work order report originally used in processing is not available. A companion paper discusses the generation of the NLAPS IC gain and bias look-up tables required to perform the recalibration.

Optical Imaging and Radiometric Modeling and Simulation

NASA Technical Reports Server (NTRS)

Ha, Kong Q.; Fitzmaurice, Michael W.; Moiser, Gary E.; Howard, Joseph M.; Le, Chi M.

2010-01-01

OPTOOL software is a general-purpose optical systems analysis tool that was developed to offer a solution to problems associated with computational programs written for the James Webb Space Telescope optical system. It integrates existing routines into coherent processes, and provides a structure with reusable capabilities that allow additional processes to be quickly developed and integrated. It has an extensive graphical user interface, which makes the tool more intuitive and friendly. OPTOOL is implemented using MATLAB with a Fourier optics-based approach for point spread function (PSF) calculations. It features parametric and Monte Carlo simulation capabilities, and uses a direct integration calculation to permit high spatial sampling of the PSF. Exit pupil optical path difference (OPD) maps can be generated using combinations of Zernike polynomials or shaped power spectral densities. The graphical user interface allows rapid creation of arbitrary pupil geometries, and entry of all other modeling parameters to support basic imaging and radiometric analyses. OPTOOL provides the capability to generate wavefront-error (WFE) maps for arbitrary grid sizes. These maps are 2D arrays containing digital sampled versions of functions ranging from Zernike polynomials to combination of sinusoidal wave functions in 2D, to functions generated from a spatial frequency power spectral distribution (PSD). It also can generate optical transfer functions (OTFs), which are incorporated into the PSF calculation. The user can specify radiometrics for the target and sky background, and key performance parameters for the instrument s focal plane array (FPA). This radiometric and detector model setup is fairly extensive, and includes parameters such as zodiacal background, thermal emission noise, read noise, and dark current. The setup also includes target spectral energy distribution as a function of wavelength for polychromatic sources, detector pixel size, and the FPA s charge diffusion modulation transfer function (MTF).

Ground-based microwave radiometric remote sensing of the tropical atmosphere

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, Yong.

1992-01-01

A partially developed 9-channel ground-based microwave radiometer for the Department of Meteorology at Penn State was completed and tested. Complementary units were added, corrections to both hardware and software were made, and system software was corrected and upgraded. Measurements from this radiometer were used to infer tropospheric temperature, water vapor and cloud liquid water. The various weighting functions at each of the 9 channels were calculated and analyzed to estimate the sensitivities of the brightness temperature to the desired atmospheric variables. The mathematical inversion problem, in a linear form, was viewed in terms of the theory of linear algebra. Severalmore » methods for solving the inversion problem were reviewed. Radiometric observations were conducted during the 1990 Tropical Cyclone Motion Experiment. The radiometer was installed on the island of Saipan in a tropical region. The radiometer was calibrated using tipping curve and radiosonde data as well as measurements of the radiation from a blackbody absorber. A linear statistical method was applied for the data inversion. The inversion coefficients in the equation were obtained using a large number of radiosonde profiles from Guam and a radiative transfer model. Retrievals were compared with those from local, Saipan, radiosonde measurements. Water vapor profiles, integrated water vapor, and integrated liquid water were retrieved successfully. For temperature profile retrievals, however, the radiometric measurements with experimental noises added no more profile information to the inversion than that they were determined mainly by the surface pressure measurements. A method was developed to derive the integrated water vapor and liquid water from combined radiometer and ceilometer measurements. Significant improvement on radiometric measurements of the integrated liquid water can be gained with this method.« less

An Overview of Lunar Calibration and Characterization for the EOS Terra and Aqua MODIS

NASA Technical Reports Server (NTRS)

Xiong, X.; Salomonson, V. V.; Sun, J.; Chiang, K.; Xiong, S.; Humphries, S.; Barnes, W.; Guenther, B.

2004-01-01

The Moon can be used as a stable source for Earth-observing sensors on-orbit radiometric and spatial stability monitoring in the VIS and NIR spectral regions. It can also serve as a calibration transfer vehicle among multiple sensors. Nearly identical copies of the Moderate Resolution Imaging Spectroradiometer (MODE) have been operating on-board the NASA's Earth Observing System (EOS) Terra and Aqua satellites since their launches in December 1999 and May 2002, respectively. Terra and Aqua MODIS each make observations in 36 spectral bands covering the spectral range from 0.41 to 14.5 microns and are calibrated on-orbit by a set of on-board calibrations (OBCs) including: 1) a solar diffuser (SD), 2) a solar diffuser stability monitor (SDSM), 3) a blackbody (BB), and 4) a spectro-radiometric calibration assembly (SRCA). In addition to fully utilizing the OBCs, the Moon has been used extensively by both Terra and Aqua MODIS to support their on-orbit calibration and characterization. A 4 This paper provides an overview of applications of lunar calibration and characterization from the MODIS perspective, including monitoring radiometric calibration stability for the reflective solar bands (RSBs), tracking changes of the sensors response versus scan-angle (RVS), examining the sensors spatial performance , and characterizing optical leaks and electronic crosstalk among different spectral bands and detectors. On-orbit calibration consistency between the two MODIS instruments is also addressed. Based on the existing on-orbit time series of the Terra and Aqua MODIS lunar observations, the radiometric difference between the two sensors is less than +/-1% for the RSBs. This method provides a powerful means of performing calibration comparisons among Earth-observing sensors and assures consistent data and science products for the long-term studies of climate and environmental changes.

The effects of hoechst 33342 staining and the male sample donor on the sorting efficiency of canine spermatozoa.

PubMed

Rodenas, C; Lucas, X; Tarantini, T; Del Olmo, D; Roca, J; Vazquez, J M; Martinez, E A; Parrilla, I

2014-02-01

The aim of this study was to evaluate the influence of Hoechst 33342 (H-42) concentration and of the male donor on the efficiency of sex-sorting procedure in canine spermatozoa. Semen samples from six dogs (three ejaculates/dog) were diluted to 100 × 10(6) sperm/ml, split into four aliquots, stained with increasing H-42 concentrations (5, 7.5, 10 and 12.5 μl, respectively) and sorted by flow cytometry. The rates of non-viable (FDA+), oriented (OS) and selected spermatozoa (SS), as well as the average sorting rates (SR, sorted spermatozoa/s), were used to determine the sorting efficiency. The effects of the sorting procedure on the quality of sorted spermatozoa were evaluated in terms of total motility (TM), percentage of viable spermatozoa (spermatozoa with membrane and acrosomal integrity) and percentage of spermatozoa with reacted/damaged acrosomes. X- and Y-chromosome-bearing sperm populations were identified in all of the samples stained with 7.5, 10 and 12.5 μl of H-42, while these two populations were only identified in 77.5% of samples stained with 5 μl. The values of OS, SS and SR were influenced by the male donor (p < 0.01) but not by the H-42 concentration used. The quality of sorted sperm samples immediately after sorting was similar to that of fresh samples, while centrifugation resulted in significant reduction (p < 0.05) in TM and in the percentage of viable spermatozoa and a significant increase (p < 0.01) in the percentage of spermatozoa with damage/reacted acrosomes. In conclusion, the sex-sorting of canine spermatozoa by flow cytometry can be performed successfully using H-42 concentrations between 7.5 and 12.5 μl. The efficiency of the sorting procedure varies based on the dog from which the sperm sample derives. © 2013 Blackwell Verlag GmbH.

Sorting out Ideas about Function

ERIC Educational Resources Information Center

Hillen, Amy F.; Malik, LuAnn

2013-01-01

Card sorting has the potential to provide opportunities for exploration of a variety of topics and levels. In a card-sorting task, each participant is presented with a set of cards--each of which depicts a relationship--and is asked to sort the cards into categories that make sense to him or her. The concept of function is critical to…

Gender Sorting across K-12 Schools in the United States

ERIC Educational Resources Information Center

Long, Mark C.; Conger, Dylan

2013-01-01

This article documents evidence of nonrandom gender sorting across K-12 schools in the United States. The sorting exists among coed schools and at all grade levels, and it is highest in the secondary school grades. We observe some gender sorting across school sectors and types: for instance, males are slightly underrepresented in private schools…

Lazarus's BASIC ID: Making Initial Client Assessments Using Q-Sorts.

ERIC Educational Resources Information Center

Miller, Mark J.

1987-01-01

Presents overview of Lazarus's multimodal therapy model and the Q-sort, an observer-evaluation scoring instrument. Outlines feasibility of integrating Q-sort within multimodal model. Describes both a preliminary attempt using expert raters to categorize Q-sort cards within the model and a case study on how to assess client by incorporating Q-sort…

Machine Vision System for Color Sorting Wood Edge-Glued Panel Parts

Treesearch

Qiang Lu; S. Srikanteswara; W. King; T. Drayer; Richard Conners; D. Earl Kline; Philip A. Araman

1997-01-01

This paper describes an automatic color sorting system for hardwood edge-glued panel parts. The color sorting system simultaneously examines both faces of a panel part and then determines which face has the "better" color given specified color uniformity and priority defined by management. The real-time color sorting system software and hardware are briefly...

Flankers Facilitate 3-Year-Olds' Performance in a Card-Sorting Task

ERIC Educational Resources Information Center

Jordan, Patricia L.; Morton, J. Bruce

2008-01-01

Three-year-old children often act inflexibly in card-sorting tasks by continuing to sort by an old rule after being asked to switch and sort by a new rule. This inflexibility has been variously attributed to age-related constraints on higher order rule use, object redescription, and attention shifting. In 2 experiments, flankers that were…

My eSorts and Digital Extensions of Word Study

ERIC Educational Resources Information Center

Zucker, Tricia A.; Invernizzi, Marcia

2008-01-01

"My eSorts" is a strategy for helping children learn to read and spell in a socially motivated context. It is based on developmental spelling research and the word study approach to teaching phonics and spelling. "eSorting" employs digital desktop publishing tools that allow children to author their own electronic word sorts and then share these…

Continuous sorting of Brownian particles using coupled photophoresis and asymmetric potential cycling.

PubMed

Ng, Tuck Wah; Neild, Adrian; Heeraman, Pascal

2008-03-15

Feasible sorters need to function rapidly and permit the input and delivery of particles continuously. Here, we describe a scheme that incorporates (i) restricted spatial input location and (ii) orthogonal sort and movement direction features. Sorting is achieved using an asymmetric potential that is cycled on and off, whereas movement is accomplished using photophoresis. Simulations with 0.2 and 0.5 microm diameter spherical particles indicate that sorting can commence quickly from a continuous stream. Procedures to optimize the sorting scheme are also described.

Application of Raman spectroscopy to identification and sorting of post-consumer plastics for recycling

DOEpatents

Sommer, Edward J.; Rich, John T.

2001-01-01

A high accuracy rapid system for sorting a plurality of waste products by polymer type. The invention involves the application of Raman spectroscopy and complex identification techniques to identify and sort post-consumer plastics for recycling. The invention reads information unique to the molecular structure of the materials to be sorted to identify their chemical compositions and uses rapid high volume sorting techniques to sort them into product streams at commercially viable throughput rates. The system employs a laser diode (20) for irradiating the material sample (10), a spectrograph (50) is used to determine the Raman spectrum of the material sample (10) and a microprocessor based controller (70) is employed to identify the polymer type of the material sample (10).

Evaluation of active and passive near-millimeter-wave radiometric imaging techniques for detection of concealed objects

NASA Astrophysics Data System (ADS)

Reber, E. E.; Foote, F. B.; Schellenbaum, R. L.; Bradley, R. G.

1981-07-01

The potential of radiometric imaging technique to detect shielded nuclear materials and explosives carried covertly by personnel was investigated. This method of detecting contraband depends upon the differences in emissivity and reflectivity of the contraband relative to human tissue. Explosives, unlike metals and metal composites, generally have high emissivities and low reflectivities that closely approximate those of human tissue making explosives difficult to detect. Samples of several common types of explosives (TNT, Detasheet, C4, and several types of water gels) were examined at the 1.4- and 3-mm wavelengths using active and passive radiometeric techniques.

Ar-39-Ar-40 Ages of Two Nakhlites, MIL03346 and Y000593: A Detailed Analysis

NASA Technical Reports Server (NTRS)

Park, Jisun; Garrison, Daniel; Bogard, Donald

2007-01-01

Radiometric dating of martian nakhlites by several techniques have given similar ages of approx.1.2-1.4 Ga [e.g. 1, 2]. Unlike the case with shergottites, where the presence of martian atmosphere and inherited radiogenic Ar-40 produce apparent Ar-39-Ar-40 ages older than other radiometric ages, Ar-Ar ages of nakhlites are similar to ages derived by other techniques. However, even in some nakhlites the presence of trapped martian Ar produces some uncertainty in the Ar-Ar age. We present here an analysis of such Ar-Ar ages from the MIL03346 and Y000593 nakhlites.

Optical radiation measurements II; Proceedings of the Meeting, Orlando, FL, Mar. 27, 28, 1989

NASA Astrophysics Data System (ADS)

Palmer, James M.

1989-09-01

The present conference discusses topics in the characterization of imaging radiometers, laboratory instrumentation, field and spacecraft instrumentation, and quantum and thermal standard detectors. Attention is given to UV radiometric imaging, dual-color radiometer imagery, a novel diode-array radiometer, a novel reference spectrophotometer, radiance calibration of spherical integrators, instrumentation for measurement of spectral goniometric reflectance, and a real-time IR background discrimination radiometer. Also discussed are a multichannel radiometer for atmosphere optical property measurements, the UV spectroradiometric output of a turbojet, characterizations of the Earth Radiation Budget Experiment scanning radiometers, total-radiation thermometry, future directions in Si photodiode self-calibration, and radiometric quality Ge photodiodes.

Local effects of partly-cloudy skies on solar and emitted radiations

NASA Technical Reports Server (NTRS)

Whitney, D. A.; Griffin, T. J.

1983-01-01

Atmospheric aerosol and turbidity measurements were analyzed and the results are presented. The correlation of global insolation with cloud cover fractions for the first complete year's data set was completed. A theoretical model was developed to parameterize the effects of local aerosols upon insolation received at the ground using satellite radiometric data and insolation measurements under clear sky conditions. A February data set, composed of one minute integrated global insolation and direct solar irradiances, cloud cover fractions, meteorological data from nearby weather stations, and GOES East satellite radiometric data was collected to test the model and used to calculate the effects of local aerosols.

Interpretation of detailed aerial gamma-ray survey, Jabal Ashirah area, southeastern Arabian Shield, Kingdom of Saudi Arabia

USGS Publications Warehouse

Duval, J.S.

1987-01-01

A detailed aerial gamma-ray spectrometric survey of the Jabal Ashirah area in the southeastern Arabian Shield has been analyzed using computer-classification algorithms. The analysis resulted in maps that show radiometric map units and gamma-ray anomalies indicating the presence of possible concentrations of potassium and uranium. The radiometric-unit map was interpreted to 'produce a simplified radiolithic map that was correlated with the mapped geology. The gamma-ray data show uranium anomalies that coincide with a tin-bearing granite, but known gold and nickel mineralization do not have any associated gamma-ray signatures.

Activities of NIST (National Inst. of Standards and Technology)

NASA Technical Reports Server (NTRS)

1992-01-01

The Radiometric Physics Division of the NIST is responsible for the national standards in radiation thermometry, spectroradiometry, photometry, and spectrophotometry; dissemination of these standards by providing measurement services to customers requiring calibrations of the highest accuracy; and conducting fundamental and applied research to develop the scientific basis for future measurement services. Its relevance to EOS/TIR calibration includes calibrating unknown blackbody for radiance using a well-characterized NIST blackbody source by matching the radiant fluxes with an IR radiometer. The TIR Round Robin is used to verify the calibration of the sources that are used for the absolute radiometric calibration of the individual EOS sensors.

Earth Observing-1 Advanced Land Imager: Radiometric Response Calibration

NASA Technical Reports Server (NTRS)

Mendenhall, J. A.; Lencioni, D. E.; Evans, J. B.

2000-01-01

The Advanced Land Imager (ALI) is one of three instruments to be flown on the first Earth Observing mission (EO-1) under NASA's New Millennium Program (NMP). ALI contains a number of innovative features, including a wide field of view optical design, compact multispectral focal plane arrays, non-cryogenic HgCdTe detectors for the short wave infrared bands, and silicon carbide optics. This document outlines the techniques adopted during ground calibration of the radiometric response of the Advanced Land Imager. Results from system level measurements of the instrument response, signal-to-noise ratio, saturation radiance, and dynamic range for all detectors of every spectral band are also presented.

A preliminary evaluation of LANDSAT-4 thematic mapper data for their geometric and radiometric accuracies

NASA Technical Reports Server (NTRS)

Podwysocki, M. H.; Bender, L. U.; Falcone, N.; Jones, O. D.

1983-01-01

Some LANDSAT thematic mapper data collected over the eastern United States were analyzed for their whole scene geometric accuracy, band to band registration and radiometric accuracy. Band ratio images were created for a part of one scene in order to assess the capability of mapping geologic units with contrasting spectral properties. Systematic errors were found in the geometric accuracy of whole scenes, part of which were attributable to the film writing device used to record the images to film. Band to band registration showed that bands 1 through 4 were registered to within one pixel. Likewise, bands 5 and 7 also were registered to within one pixel. However, bands 5 and 7 were misregistered with bands 1 through 4 by 1 to 2 pixels. Band 6 was misregistered by 4 pixels to bands 1 through 4. Radiometric analysis indicated two kinds of banding, a modulo-16 stripping and an alternate light dark group of 16 scanlines. A color ratio composite image consisting of TM band ratios 3/4, 5/2, and 5/7 showed limonitic clay rich soils, limonitic clay poor soils, and nonlimonitic materials as distinctly different colors on the image.

A Review of LIDAR Radiometric Processing: From Ad Hoc Intensity Correction to Rigorous Radiometric Calibration.

PubMed

Kashani, Alireza G; Olsen, Michael J; Parrish, Christopher E; Wilson, Nicholas

2015-11-06

In addition to precise 3D coordinates, most light detection and ranging (LIDAR) systems also record "intensity", loosely defined as the strength of the backscattered echo for each measured point. To date, LIDAR intensity data have proven beneficial in a wide range of applications because they are related to surface parameters, such as reflectance. While numerous procedures have been introduced in the scientific literature, and even commercial software, to enhance the utility of intensity data through a variety of "normalization", "correction", or "calibration" techniques, the current situation is complicated by a lack of standardization, as well as confusing, inconsistent use of terminology. In this paper, we first provide an overview of basic principles of LIDAR intensity measurements and applications utilizing intensity information from terrestrial, airborne topographic, and airborne bathymetric LIDAR. Next, we review effective parameters on intensity measurements, basic theory, and current intensity processing methods. We define terminology adopted from the most commonly-used conventions based on a review of current literature. Finally, we identify topics in need of further research. Ultimately, the presented information helps lay the foundation for future standards and specifications for LIDAR radiometric calibration.

A Review of LIDAR Radiometric Processing: From Ad Hoc Intensity Correction to Rigorous Radiometric Calibration

PubMed Central

Kashani, Alireza G.; Olsen, Michael J.; Parrish, Christopher E.; Wilson, Nicholas

2015-01-01

In addition to precise 3D coordinates, most light detection and ranging (LIDAR) systems also record “intensity”, loosely defined as the strength of the backscattered echo for each measured point. To date, LIDAR intensity data have proven beneficial in a wide range of applications because they are related to surface parameters, such as reflectance. While numerous procedures have been introduced in the scientific literature, and even commercial software, to enhance the utility of intensity data through a variety of “normalization”, “correction”, or “calibration” techniques, the current situation is complicated by a lack of standardization, as well as confusing, inconsistent use of terminology. In this paper, we first provide an overview of basic principles of LIDAR intensity measurements and applications utilizing intensity information from terrestrial, airborne topographic, and airborne bathymetric LIDAR. Next, we review effective parameters on intensity measurements, basic theory, and current intensity processing methods. We define terminology adopted from the most commonly-used conventions based on a review of current literature. Finally, we identify topics in need of further research. Ultimately, the presented information helps lay the foundation for future standards and specifications for LIDAR radiometric calibration. PMID:26561813

CIRiS: Compact Infrared Radiometer in Space

NASA Astrophysics Data System (ADS)

Osterman, D. P.; Collins, S.; Ferguson, J.; Good, W.; Kampe, T.; Rohrschneider, R.; Warden, R.

2016-09-01

The Compact Infrared Radiometer in Space (CIRiS) is a thermal infrared radiometric imaging instrument under development by Ball Aerospace for a Low Earth Orbit mission on a CubeSat spacecraft. Funded by the NASA Earth Science Technology Office's In-Space Validation of Earth Science Technology (InVEST) program, the mission objective is technology demonstration for improved on-orbit radiometric calibration. The CIRiS calibration approach uses a scene select mirror to direct three calibration views to the focal plane array and to transfer the resulting calibrated response to earth images. The views to deep space and two blackbody sources, including one at a selectable temperature, provide multiple options for calibration optimization. Two new technologies, carbon nanotube blackbody sources and microbolometer focal plane arrays with reduced pixel sizes, enable improved radiometric performance within the constrained 6U CubeSat volume. The CIRiS instrument's modular design facilitates subsystem modifications as required by future mission requirements. CubeSat constellations of CIRiS and derivative instruments offer an affordable approach to achieving revisit times as short as one day for diverse applications including water resource and drought management, cloud, aerosol, and dust studies, and land use and vegetation monitoring. Launch is planned for 2018.

Thermal return reflection method for resolving emissivity and temperature in radiometric measurements

NASA Astrophysics Data System (ADS)

Woskov, P. P.; Sundaram, S. K.

2002-11-01

A radiometric method for resolving emissivity epsilon and temperature T in thermal emission measurements is presented. Thermal radiation from a viewed source is split by a beamsplitter between a radiometer and a mirror aligned to return a part of the thermal radiation back to the source. The ratio of the thermal signal with and without a return reflection provides a measurement of the emissivity without need of any other probing sources. The analytical expressions that establish this relationship are derived taking into account waveguide/optic losses and sources between the radiometer and viewed sample. The method is then applied to thermal measurements of several refractory materials at temperatures up to 1150 degC. A 137 GHz radiometer is used to measure the emissivity and temperature of an alumina brick, an Inconel 690 plate, and two grades of silicon carbide. Reasonable temperature agreement is achieved with an independent thermocouple measurement. However, when the emissivity approaches zero, as in the case of the Inconel plate, radiometric temperature determinations are inaccurate, though an emissivity near zero is correctly measured. This method is expected to be of considerable value to noncontact thermal analysis applications of materials.

Relative radiometric calibration for multispectral remote sensing imagery

NASA Astrophysics Data System (ADS)

Ren, Hsuan

2006-10-01

Our environment has been changed continuously by nature causes or human activities. In order to identify what has been changed during certain time period, we need to spend enormous resources to collect all kinds of data and analyze them. With remote sensing images, change detection has become one efficient and inexpensive technique. It has wide applications including disaster management, agriculture analysis, environmental monitoring and military reconnaissance. To detect the changes between two remote sensing images collected at different time, radiometric calibration is one of the most important processes. Under the different weather and atmosphere conditions, even the same material might be resulting distinct radiance spectrum in two images. In this case, they will be misclassified as changes and false alarm rate will also increase. To achieve absolute calibration, i.e., to convert the radiance to reflectance spectrum, the information about the atmosphere condition or ground reference materials with known reflectance spectrum is needed but rarely available. In this paper, we present relative radiometric calibration methods which transform image pair into similar atmospheric effect instead of remove it in absolutely calibration, so that the information of atmosphere condition is not required. A SPOT image pair will be used for experiment to demonstrate the performance.

PTB’s radiometric scales for UV and VUV source calibration based on synchrotron radiation

NASA Astrophysics Data System (ADS)

Klein, Roman; Kroth, Simone; Paustian, Wolfgang; Richter, Mathias; Thornagel, Reiner

2018-06-01

The radiant intensity of synchrotron radiation can be accurately calculated with classical electrodynamics. This primary realization of the spectral radiant intensity has been used by PTB at several electron storage rings which have been optimized to be operated as primary source standards for the calibration of transfer sources in the spectral range of UV and VUV for almost 30 years. The transfer sources are compared to the primary source standard by means of suitable wavelength-dispersive transfer stations. The spectral range covered by deuterium lamps, which represent transfer sources that are easy to handle, is of particular relevance in practice. Here, we report on developments in the realization and preservation of the radiometric scales for spectral radiant intensity and spectral radiance in the wavelength region from 116 nm to 400 nm, based on a set of deuterium reference lamps, over the last few decades. An inside view and recommendations on the operation of the D2 lamps used for the realization of the radiometric scale are presented. The data has been recently compiled to illustrate the chronological behaviour at various wavelengths. Moreover, an overview of the internal and external validation measurements and intercomparisons is given.

Multipurpose Spectroradiometer for Satellite Instrument Calibration and Zenith Sky Remote Sensing Measurements

NASA Technical Reports Server (NTRS)

Heath, Donald F.; Ahmad, Zia

2001-01-01

In the early 1990s a series of surface-based direct sun and zenith sky measurements of total column ozone were made with SBUV/2 flight models and the SSBUV Space Shuttle instrument in Boulder, Colorado which were compared with NOAA Dobson Instrument direct sun observations and TOMS instrument overpass observations of column ozone. These early measurements led to the investigation of the accuracy of derived total column ozone amounts and aerosol optical depths from zenith sky observations. Following the development and availability of radiometrically stable IAD narrow band interference filter and nitrided silicon photodiodes a simple compact multifilter spectroradiometer was developed which can be used as a calibration transfer standard spectroradiometer (CTSS) or as a surface based instrument remote sensing instruments for measurements of total column ozone and aerosol optical depths. The total column ozone derived from zenith sky observations agrees with Dobson direct sun AD double wavelength pair measurements and with TOMS overpass ozone amounts within uncertainties of about 1%. When used as a calibration transfer standard spectroradiometer the multifilter spectroradiometer appears to be capable of establishing instrument radiometric calibration uncertainties of the order of 1% or less relative to national standards laboratory radiometric standards.

Geochronological correlation of the main coal interval in Brazilian Lower Permian: Radiometric dating of tonstein and calibration of biostratigraphic framework

NASA Astrophysics Data System (ADS)

Simas, Margarete Wagner; Guerra-Sommer, Margot; Cazzulo-Klepzig, Miriam; Menegat, Rualdo; Schneider Santos, João Orestes; Fonseca Ferreira, José Alcides; Degani-Schmidt, Isabela

2012-11-01

The radiometric age of 291 ± 1.2 Ma obtained through single-crystal zircon U-Pb ages (Sensitive High Resolution Ion MicroProbe - SHRIMP II) of tonsteins from the Leão-Butiá Coalfield, southern Paraná Basin (Rio Grande do Sul state), associated with previous SHRIMP II radiometric data obtained from tonsteins from the western (Candiota Coalfield) and eastern (Faxinal and Leão-Butiá coalfields) borders of the basin indicate that the mean age of the main peat-forming interval is 291.0 ± 1.3 Ma. In a regional context, the mean age represents a consistent geochronological correlation for the uppermost and more important coal seams in southern Brazilian coalfields, but this assumption does not establish an ash fall origin from a single volcanic event. According to the International Stratigraphic Chart, the interval is dated as middle Sakmarian. The coal palynofloras are included in the Protohaploxypinus goraiensis Subzone within the palynostratigraphic framework for the Brazilian Paraná Basin. Formal relationships are also established with the Glossopteris-Rhodeopteridium Zone within the phytostratigraphic chart for the Lower Permian of southern Brazilian Paraná Basin.

Radiometric calibration method for large aperture infrared system with broad dynamic range.

PubMed

Sun, Zhiyuan; Chang, Songtao; Zhu, Wei

2015-05-20

Infrared radiometric measurements can acquire important data for missile defense systems. When observation is carried out by ground-based infrared systems, a missile is characterized by long distance, small size, and large variation of radiance. Therefore, the infrared systems should be manufactured with a larger aperture to enhance detection ability and calibrated at a broader dynamic range to extend measurable radiance. Nevertheless, the frequently used calibration methods demand an extended-area blackbody with broad dynamic range or a huge collimator for filling the system's field stop, which would greatly increase manufacturing costs and difficulties. To overcome this restriction, a calibration method based on amendment of inner and outer calibration is proposed. First, the principles and procedures of this method are introduced. Then, a shifting strategy of infrared systems for measuring targets with large fluctuations of infrared radiance is put forward. Finally, several experiments are performed on a shortwave infrared system with Φ400  mm aperture. The results indicate that the proposed method cannot only ensure accuracy of calibration but have the advantage of low cost, low power, and high motility. Hence, it is an effective radiometric calibration method in the outfield.

Multivariate analysis of subsurface radiometric data in Rongsohkham area, East Khasi Hills district, Meghalaya (India): implication on uranium exploration.

PubMed

Kukreti, B M; Pandey, Pradeep; Singh, R V

2012-08-01

Non-coring based exploratory drilling was under taken in the sedimentary environment of Rangsohkham block, East Khasi Hills district to examine the eastern extension of existing uranium resources located at Domiasiat and Wakhyn in the Mahadek basin of Meghalaya (India). Although radiometric survey and radiometric analysis of surface grab/channel samples in the block indicate high uranium content but the gamma ray logging results of exploratory boreholes in the block, did not obtain the expected results. To understand this abrupt discontinuity between the two sets of data (surface and subsurface) multivariate statistical analysis of primordial radioactive elements (K(40), U(238) and Th(232)) was performed using the concept of representative subsurface samples, drawn from the randomly selected 11 boreholes of this block. The study was performed to a high confidence level (99%), and results are discussed for assessing the U and Th behavior in the block. Results not only confirm the continuation of three distinct geological formations in the area but also the uranium bearing potential in the Mahadek sandstone of the eastern part of Mahadek Basin. Copyright © 2012 Elsevier Ltd. All rights reserved.

Projection technologies for imaging sensor calibration, characterization, and HWIL testing at AEDC

NASA Astrophysics Data System (ADS)

Lowry, H. S.; Breeden, M. F.; Crider, D. H.; Steely, S. L.; Nicholson, R. A.; Labello, J. M.

2010-04-01

The characterization, calibration, and mission simulation testing of imaging sensors require continual involvement in the development and evaluation of radiometric projection technologies. Arnold Engineering Development Center (AEDC) uses these technologies to perform hardware-in-the-loop (HWIL) testing with high-fidelity complex scene projection technologies that involve sophisticated radiometric source calibration systems to validate sensor mission performance. Testing with the National Institute of Standards and Technology (NIST) Ballistic Missile Defense Organization (BMDO) transfer radiometer (BXR) and Missile Defense Agency (MDA) transfer radiometer (MDXR) offers improved radiometric and temporal fidelity in this cold-background environment. The development of hardware and test methodologies to accommodate wide field of view (WFOV), polarimetric, and multi/hyperspectral imaging systems is being pursued to support a variety of program needs such as space situational awareness (SSA). Test techniques for the acquisition of data needed for scene generation models (solar/lunar exclusion, radiation effects, etc.) are also needed and are being sought. The extension of HWIL testing to the 7V Chamber requires the upgrade of the current satellite emulation scene generation system. This paper provides an overview of pertinent technologies being investigated and implemented at AEDC.

Radiometrie recalibration procedure for landsat-5 thematic mapper data

USGS Publications Warehouse

Chander, G.; Micijevic, E.; Hayes, R.W.; Barsi, J.A.

2008-01-01

The Landsat-5 (L5) satellite was launched on March 01, 1984, with a design life of three years. Incredibly, the L5 Thematic Mapper (TM) has collected data for 23 years. Over this time, the detectors have aged, and its radiometric characteristics have changed since launch. The calibration procedures and parameters have also changed with time. Revised radiometric calibrations have improved the radiometric accuracy of recently processed data; however, users with data that were processed prior to the calibration update do not benefit from the revisions. A procedure has been developed to give users the ability to recalibrate their existing Level 1 (L1) products without having to purchase reprocessed data from the U.S. Geological Survey (USGS). The accuracy of the recalibration is dependent on the knowledge of the prior calibration applied to the data. The ""Work Order" file, included with standard National Land Archive Production System (NLAFS) data products, gives parameters that define the applied calibration. These are the Internal Calibrator (IC) calibration parameters or the default prelaunch calibration, if there were problems with the IC calibration. This paper details the recalibration procedure for data processed using IC, in which users have the Work Order file. ?? 2001 IEEE.

Landsat-7 ETM+ Radiometric Calibration Status

NASA Technical Reports Server (NTRS)

Barsi, Julia A.; Markham, Brian L.; Czapla-Myers, Jeffrey S.; Helder, Dennis L.; Hook, Simon J.; Schott, John R; Haque, Md. Obaidul

2016-01-01

Now in its 17th year of operation, the Enhanced Thematic Mapper + (ETM+), on board the Landsat-7 satellite, continues to systematically acquire imagery of the Earth to add to the 40+ year archive of Landsat data. Characterization of the ETM+ on-orbit radiometric performance has been on-going since its launch in 1999. The radiometric calibration of the reflective bands is still monitored using on-board calibration devices, though the Pseudo-Invariant Calibration Sites (PICS) method has proven to be an effect tool as well. The calibration gains were updated in April 2013 based primarily on PICS results, which corrected for a change of as much as -0.2%/year degradation in the worst case bands. A new comparison with the SADE database of PICS results indicates no additional degradation in the updated calibration. PICS data are still being tracked though the recent trends are not well understood. The thermal band calibration was updated last in October 2013 based on a continued calibration effort by NASA/Jet Propulsion Lab and Rochester Institute of Technology. The update accounted for a 0.31 W/sq m/ sr/micron bias error. The updated lifetime trend is now stable to within + 0.4K.

Assessment of the short-term radiometric stability between Terra MODIS and Landsat 7 ETM+ sensors

USGS Publications Warehouse

Choi, Taeyoung; Xiong, Xiaoxiong; Chander, Gyanesh; Angal, A.

2009-01-01

Short-term radiometric stability was evaluated using continuous ETM+ scenes within a single orbit (contact period) and the corresponding MODIS scenes for the four matching solar reflective visible and near-infrared (VNIR) band pairs between the two sensors. The near-simultaneous earth observations were limited by the smaller swath size of ETM+ (183 km) compared to MODIS (2330 km). Two sets of continuous granules for Terra MODIS and Landsat 7 ETM+ were selected and mosaicked based on pixel geolocation information for noncloudy pixels over the African continent. The matching pixel pairs were resampled from a fine to a coarse pixel resolution, and the at-sensor spectral radiance values for a wide dynamic range of the sensors were compared and analyzed, covering various surface types. The following study focuses on radiometric stability analysis from the VNIR band-pairs of ETM+ and MODIS. The Libya-4 desert target was included in the path of this continuous orbit, which served as a verification point between the short-term and the long-term trending results from previous studies. MODTRAN at-sensor spectral radiance simulation is included for a representative desert surface type to evaluate the consistency of the results.

Branching Ratios for The Radiometric Calibration of EUNIS-2012

NASA Technical Reports Server (NTRS)

Daw, Adrian N.; Bhatia, A. K.; Rabin, Douglas M.

2012-01-01

The Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS) sounding rocket instrument is a two-channel imaging spectrograph that observes the solar corona and transition region with high spectral resolution and a rapid cadence made possible by unprecedented sensitivity. The upcoming flight will incorporate a new wavelength channel covering the range 524-630 Angstroms, the previously-flown 300-370 Angstroms channel, and the first flight demonstration of cooled active pixel sensor (APS) arrays. The new 524-630 Angstrom channel incorporates a Toroidal Varied Line Space (TVLS) grating coated with B4C/Ir, providing broad spectral coverage and a wide temperature range of 0.025 to 10 MK. Absolute radiometric calibration of the two channels is being performed using a hollow cathode discharge lamp and NIST-calibrated AXUV-100G photodiode. Laboratory observations of He I 584 Angstroms and He II 304 Angstroms provide absolute radiometric calibrations of the two channels at those two respective wavelengths by using the AXUV photodiode as a transfer standard. The spectral responsivity is being determined by observing line pairs with a common upper state in the spectra of Ne I-III and Ar II-III. Calculations of A-values for the observed branching ratios are in progress.

The Future Spaceborne Hyperspectral Imager Enmap: its In-Flight Radiometric and Geometric Calibration Concept

NASA Astrophysics Data System (ADS)

Schneider, M.; Müller, R.; Krawzcyk, H.; Bachmann, M.; Storch, T.; Mogulsky, V.; Hofer, S.

2012-07-01

The German Aerospace Center DLR - namely the Earth Observation Center EOC and the German Space Operations Center GSOC - is responsible for the establishment of the ground segment of the future German hyperspectral satellite mission EnMAP (Environmental Mapping and Analysis Program). The Earth Observation Center has long lasting experiences with air- and spaceborne acquisition, processing, and analysis of hyperspectral image data. In the first part of this paper, an overview of the radiometric in-flight calibration concept including dark value measurements, deep space measurements, internal lamps measurements and sun measurements is presented. Complemented by pre-launch calibration and characterization these analyses will deliver a detailed and quantitative assessment of possible changes of spectral and radiometric characteristics of the hyperspectral instrument, e.g. due to degradation of single elements. A geometric accuracy of 100 m, which will be improved to 30 m with respect to a used reference image, if it exists, will be achieved by ground processing. Therfore, and for the required co-registration accuracy between SWIR and VNIR channels, additional to the radiometric calibration, also a geometric calibration is necessary. In the second part of this paper, the concept of the geometric calibration is presented in detail. The geometric processing of EnMAP scenes will be based on laboratory calibration results. During repeated passes over selected calibration areas images will be acquired. The update of geometric camera model parameters will be done by an adjustment using ground control points, which will be extracted by automatic image matching. In the adjustment, the improvements of the attitude angles (boresight angles), the improvements of the interior orientation (view vector) and the improvements of the position data are estimated. In this paper, the improvement of the boresight angles is presented in detail as an example. The other values and combinations follow the same rules. The geometric calibration will mainly be executed during the commissioning phase, later in the mission it is only executed if required, i.e. if the geometric accuracy of the produced images is close to or exceeds the requirements of 100 m or 30 m respectively, whereas the radiometric calibration will be executed periodically during the mission with a higher frequency during commissioning phase.

Unsupervised neural spike sorting for high-density microelectrode arrays with convolutive independent component analysis.

PubMed

Leibig, Christian; Wachtler, Thomas; Zeck, Günther

2016-09-15

Unsupervised identification of action potentials in multi-channel extracellular recordings, in particular from high-density microelectrode arrays with thousands of sensors, is an unresolved problem. While independent component analysis (ICA) achieves rapid unsupervised sorting, it ignores the convolutive structure of extracellular data, thus limiting the unmixing to a subset of neurons. Here we present a spike sorting algorithm based on convolutive ICA (cICA) to retrieve a larger number of accurately sorted neurons than with instantaneous ICA while accounting for signal overlaps. Spike sorting was applied to datasets with varying signal-to-noise ratios (SNR: 3-12) and 27% spike overlaps, sampled at either 11.5 or 23kHz on 4365 electrodes. We demonstrate how the instantaneity assumption in ICA-based algorithms has to be relaxed in order to improve the spike sorting performance for high-density microelectrode array recordings. Reformulating the convolutive mixture as an instantaneous mixture by modeling several delayed samples jointly is necessary to increase signal-to-noise ratio. Our results emphasize that different cICA algorithms are not equivalent. Spike sorting performance was assessed with ground-truth data generated from experimentally derived templates. The presented spike sorter was able to extract ≈90% of the true spike trains with an error rate below 2%. It was superior to two alternative (c)ICA methods (≈80% accurately sorted neurons) and comparable to a supervised sorting. Our new algorithm represents a fast solution to overcome the current bottleneck in spike sorting of large datasets generated by simultaneous recording with thousands of electrodes. Copyright © 2016 Elsevier B.V. All rights reserved.

Automatic Color Sorting of Hardwood Edge-Glued Panel Parts

Treesearch

D. Earl Kline; Richard Conners; Qiang Lu; Philip A. Araman

1997-01-01

This paper describes an automatic color sorting system for red oak edge-glued panel parts. The color sorting system simultaneously examines both faces of a panel part and then determines which face has the "best" color, and sorts the part into one of a number of color classes at plant production speeds. Initial test results show that the system generated over...

Two Types of Perseveration in the Dimension Change Card Sort Task

ERIC Educational Resources Information Center

Hanania, Rima

2010-01-01

In the Dimension Change Card Sort (DCCS) task, 3-year-olds can sort cards well by one dimension but have difficulty in switching to sort the same cards by another dimension when asked; that is, they perseverate on the first relevant information. What is the information that children perseverate on? Using a new version of the DCCS, the experiments…

Cell-Free Reconstitution of Multivesicular Body Formation and Receptor Sorting

PubMed Central

Sun, Wei; Vida, Thomas A.; Sirisaengtaksin, Natalie; Merrill, Samuel A.; Hanson, Phyllis I.; Bean, Andrew J.

2010-01-01

The number of surface membrane proteins and their residence time on the plasma membrane are critical determinants of cellular responses to cues that can control plasticity, growth and differentiation. After internalization, the ultimate fate of many plasma membrane proteins is dependent on whether they are sorted for internalization into the lumenal vesicles of multivesicular bodies (MVBs), an obligate step prior to lysosomal degradation. To help to elucidate the mechanisms underlying MVB sorting, we have developed a novel cell-free assay that reconstitutes the sorting of a prototypical membrane protein, the epidermal growth factor receptor, with which we have probed some of its molecular requirements. The sorting event measured is dependent on cytosol, ATP, time, temperature and an intact proton gradient. Depletion of Hrs inhibited biochemical and morphological measures of sorting that were rescued by inclusion of recombinant Hrs in the assay. Moreover, depletion of signal-transducing adaptor molecule (STAM), or addition of mutated ATPase-deficient Vps4, also inhibited sorting. This assay reconstitutes the maturation of late endosomes, including the formation of internal vesicles and the sorting of a membrane protein, and allows biochemical investigation of this process. PMID:20214752

An Unsupervised Online Spike-Sorting Framework.

PubMed

Knieling, Simeon; Sridharan, Kousik S; Belardinelli, Paolo; Naros, Georgios; Weiss, Daniel; Mormann, Florian; Gharabaghi, Alireza

2016-08-01

Extracellular neuronal microelectrode recordings can include action potentials from multiple neurons. To separate spikes from different neurons, they can be sorted according to their shape, a procedure referred to as spike-sorting. Several algorithms have been reported to solve this task. However, when clustering outcomes are unsatisfactory, most of them are difficult to adjust to achieve the desired results. We present an online spike-sorting framework that uses feature normalization and weighting to maximize the distinctiveness between different spike shapes. Furthermore, multiple criteria are applied to either facilitate or prevent cluster fusion, thereby enabling experimenters to fine-tune the sorting process. We compare our method to established unsupervised offline (Wave_Clus (WC)) and online (OSort (OS)) algorithms by examining their performance in sorting various test datasets using two different scoring systems (AMI and the Adamos metric). Furthermore, we evaluate sorting capabilities on intra-operative recordings using established quality metrics. Compared to WC and OS, our algorithm achieved comparable or higher scores on average and produced more convincing sorting results for intra-operative datasets. Thus, the presented framework is suitable for both online and offline analysis and could substantially improve the quality of microelectrode-based data evaluation for research and clinical application.

Design of mechanical arm for an automatic sorting system of recyclable cans

NASA Astrophysics Data System (ADS)

Resti, Y.; Mohruni, A. S.; Burlian, F.; Yani, I.; Amran, A.

2018-04-01

The use of a mechanical arm for an automatic sorting system of used cans should be designed carefully. The right design will result in a high precision sorting rate and a short sorting time. The design includes first; design manipulator,second; determine link and joint specifications, and third; build mechanical systems and control systems. This study aims to design the mechanical arm as a hardware system for automatic cans sorting system. The material used for the manipulator is the aluminum plate. The manipulator is designed using 6 links and 6 join where the 6th link is the end effectorand the 6th join is the gripper. As a driving motor used servo motor, while as a microcontroller used Arduino Uno which is connected with Matlab programming language. Based on testing, a mechanical arm designed for this recyclable canned recycling system has a precision sorting rate at 93%, where the average total time required for sorting is 10.82 seconds.

Low power and high accuracy spike sorting microprocessor with on-line interpolation and re-alignment in 90 nm CMOS process.

PubMed

Chen, Tung-Chien; Ma, Tsung-Chuan; Chen, Yun-Yu; Chen, Liang-Gee

2012-01-01

Accurate spike sorting is an important issue for neuroscientific and neuroprosthetic applications. The sorting of spikes depends on the features extracted from the neural waveforms, and a better sorting performance usually comes with a higher sampling rate (SR). However for the long duration experiments on free-moving subjects, the miniaturized and wireless neural recording ICs are the current trend, and the compromise on sorting accuracy is usually made by a lower SR for the lower power consumption. In this paper, we implement an on-chip spike sorting processor with integrated interpolation hardware in order to improve the performance in terms of power versus accuracy. According to the fabrication results in 90nm process, if the interpolation is appropriately performed during the spike sorting, the system operated at the SR of 12.5 k samples per second (sps) can outperform the one not having interpolation at 25 ksps on both accuracy and power.

Algorithm Sorts Groups Of Data

NASA Technical Reports Server (NTRS)

Evans, J. D.

1987-01-01

For efficient sorting, algorithm finds set containing minimum or maximum most significant data. Sets of data sorted as desired. Sorting process simplified by reduction of each multielement set of data to single representative number. First, each set of data expressed as polynomial with suitably chosen base, using elements of set as coefficients. Most significant element placed in term containing largest exponent. Base selected by examining range in value of data elements. Resulting series summed to yield single representative number. Numbers easily sorted, and each such number converted back to original set of data by successive division. Program written in BASIC.

Chip-based droplet sorting

DOEpatents

Beer, Neil Reginald; Lee, Abraham; Hatch, Andrew

2014-07-01

A non-contact system for sorting monodisperse water-in-oil emulsion droplets in a microfluidic device based on the droplet's contents and their interaction with an applied electromagnetic field or by identification and sorting.

A QR code identification technology in package auto-sorting system

NASA Astrophysics Data System (ADS)

di, Yi-Juan; Shi, Jian-Ping; Mao, Guo-Yong

2017-07-01

Traditional manual sorting operation is not suitable for the development of Chinese logistics. For better sorting packages, a QR code recognition technology is proposed to identify the QR code label on the packages in package auto-sorting system. The experimental results compared with other algorithms in literatures demonstrate that the proposed method is valid and its performance is superior to other algorithms.

When Seeing Is Knowing: The Role of Visual Cues in the Dissociation between Children's Rule Knowledge and Rule Use

ERIC Educational Resources Information Center

Buss, Aaron T.; Spencer, John P.

2012-01-01

The Dimensional Change Card Sort (DCCS) task requires children to switch from sorting cards based on shape or color to sorting based on the other dimension. Typically, 3-year-olds perseverate, whereas 4-year-olds flexibly sort by different dimensions. Zelazo and colleagues (1996, Cognitive Development, 11, 37-63) asked children questions about the…

Technology to sort lumber by color and grain for furniture parts

Treesearch

D. Earl Kline; Richard Conners; Philip A. Araman

2000-01-01

This paper describes an automatic color and grain sorting system for wood edge-glued panel parts. The color sorting system simultaneously examines both faces of a panel part and then determines which face has the "best" color, and sorts the part into one of a number of color classes at plant production speeds. In-plant test results show that the system...

BayesMotif: de novo protein sorting motif discovery from impure datasets.

PubMed

Hu, Jianjun; Zhang, Fan

2010-01-18

Protein sorting is the process that newly synthesized proteins are transported to their target locations within or outside of the cell. This process is precisely regulated by protein sorting signals in different forms. A major category of sorting signals are amino acid sub-sequences usually located at the N-terminals or C-terminals of protein sequences. Genome-wide experimental identification of protein sorting signals is extremely time-consuming and costly. Effective computational algorithms for de novo discovery of protein sorting signals is needed to improve the understanding of protein sorting mechanisms. We formulated the protein sorting motif discovery problem as a classification problem and proposed a Bayesian classifier based algorithm (BayesMotif) for de novo identification of a common type of protein sorting motifs in which a highly conserved anchor is present along with a less conserved motif regions. A false positive removal procedure is developed to iteratively remove sequences that are unlikely to contain true motifs so that the algorithm can identify motifs from impure input sequences. Experiments on both implanted motif datasets and real-world datasets showed that the enhanced BayesMotif algorithm can identify anchored sorting motifs from pure or impure protein sequence dataset. It also shows that the false positive removal procedure can help to identify true motifs even when there is only 20% of the input sequences containing true motif instances. We proposed BayesMotif, a novel Bayesian classification based algorithm for de novo discovery of a special category of anchored protein sorting motifs from impure datasets. Compared to conventional motif discovery algorithms such as MEME, our algorithm can find less-conserved motifs with short highly conserved anchors. Our algorithm also has the advantage of easy incorporation of additional meta-sequence features such as hydrophobicity or charge of the motifs which may help to overcome the limitations of PWM (position weight matrix) motif model.

Sorted bedforms developed on sandy lobes fed by small ephemeral streams (Catalan continental shelf)

NASA Astrophysics Data System (ADS)

Durán, R.; Guillén, J.; Muñoz, A.; Guerrero, Q.

2016-12-01

The morphology and sedimentological characteristics of sorted bedforms identified in the Catalan continental shelf (NW Mediterranean Sea) have been characterized using multibeam echosounder data and sediment samples collected in 2013 within the FORMED project. Bathymetric data was compared with previous data gathered in 2004 within the ESPACE project to assess the decadal stability of these bedforms. The sorted bedforms were observed on the inner shelf at water depths from 10 to 40 m, along a coastal stretch of more than 3 km. They are associated with elongated patches of low backscatter, corresponding to fine sand. The fine-grained sediment patches are located off small bays fed by short, intermittent streams, extending down to 40 m water depth. The sorted bedforms exhibit elongated shapes with subtle relief (up to 1 m) and are oriented nearly perpendicular to the shoreline. In cross-section, the sorted bedforms display lateral symmetry in bathymetric relief and backscatter, with high backscatter corresponding to poorly sorted coarse sand (median size of 0.55-0.96 mm) centered on the bathymetric depression, and low backscatter consisting of well-sorted fine to medium sand (median sized of 0.22-0.35 mm) on the crest. The local input of well-sorted fine sand supplied by ephemeral streams over the coarse sand domain of the infralittoral prograding wedge contributes to the bed sediment heterogeneity (mixture of sediment), which is further reorganized into sorted bedforms. The sorted bedforms are better developed in deeper waters (20-40 m) than near the shoreline, probably due to stronger wave forcing in the shallower shelf that prevents the maintenance of these morphologies. At a decadal time scale, the morphological evolution of these bedforms indicates that they are persistent features, showing small changes in their boundaries, which is in agreement with previous observations and numerical simulations that highlighted the persistence and long-term stability of sorted bedforms at water depths greater than 15-20 m over annual or even decadal timescales.

Put your hands up! Gesturing improves preschoolers' executive function.

PubMed

Rhoads, Candace L; Miller, Patricia H; Jaeger, Gina O

2018-09-01

This study addressed the causal direction of a previously reported relation between preschoolers' gesturing and their executive functioning on the Dimensional Change Card Sort (DCCS) sorting-switch task. Gesturing the relevant dimension for sorting was induced in a Gesture group through instructions, imitation, and prompts. In contrast, the Control group was instructed to "think hard" when sorting. Preschoolers (N = 50) performed two DCCS tasks: (a) sort by size and then spatial orientation of two objects and (b) sort by shape and then proximity of the two objects. An examination of performance over trials permitted a fine-grained depiction of patterns of younger and older children in the Gesture and Control conditions. After the relevant dimension was switched, the Gesture group had more accurate sorts than the Control group, particularly among younger children on the second task. Moreover, the amount of gesturing predicted the number of correct sorts among younger children on the second task. The overall association between gesturing and sorting was not reflected at the level of individual trials, perhaps indicating covert gestural representation on some trials or the triggering of a relevant verbal representation by the gesturing. The delayed benefit of gesturing, until the second task, in the younger children may indicate a utilization deficiency. Results are discussed in terms of theories of gesturing and thought. The findings open up a new avenue of research and theorizing about the possible role of gesturing in emerging executive function. Copyright © 2018 Elsevier Inc. All rights reserved.

[CD34(+)/CD123(+) cell sorting from the patients with leukemia by Midi MACS method].

PubMed

Wang, Guang-Ping; Cao, Xin-Yu; Xin, Hong-Ya; Li, Qun; Qi, Zhen-Hua; Chen, Fang-Ping

2006-10-01

The aim of this study was to sort the CD34(+)/CD123(+) cells from the bone marrow cells of patients with acute myeloid leukemia (AML) by Midi MACS method. Firstly, the bone marrow mononuclear cells (BMMNC) were isolated from the patients with AML with Ficoll Paque, CD34(+) cells were then isolated by Midi MACS method followed by the isolation of CD34(+)/CD123(+) cells from the fraction of CD34(+) cells. The enrichment and recovery of CD34(+) and CD34(+)/CD123(+) cells were assayed by FACS technique. The results showed that the enrichment of CD34(+) cells was up to 98.73%, its average enrichment was 95.6%, and the recovery of CD34(+) was 84.6%, its average recovery was 51% after the first round sorting, by the second round sorting, the enrichment of CD34(+)/CD123(+) cells was up to 99.23%, its average enrichment was 83%. With regard to BMMNCs before sorting, the recovery of CD34(+)/CD123(+) was 34%. But, on the CD34(+) cells obtained by the first round sorting, its recovery was 56%. In conclusion, these results confirmed that the method of Midi MACS sorting can be applied to sort CD34(+)/CD123(+) cells from the bone marrow cells of AML patients, which give rise to the similar enrichment and recovery of the sorted cells with that of literature reported by the method of FACS.

Perseveration and the Status of 3-Year-Olds' Knowledge in a Card-Sorting Task: Evidence from Studies Involving Congruent Flankers

ERIC Educational Resources Information Center

Jordan, Patricia L.; Morton, J. Bruce

2012-01-01

Infants and young children often perseverate despite apparent knowledge of the correct response. Two Experiments addressed questions concerning the status of such knowledge in the context of a card-sorting task. In Experiment 1, three groups of 3-year-olds sorted bivalent cards one way and then were instructed to switch and sort the same cards…

Activation of epidermal growth factor receptor mediates receptor axon sorting and extension in the developing olfactory system of the moth Manduca sexta.

PubMed

Gibson, Nicholas J; Tolbert, Leslie P

2006-04-10

During development of the adult olfactory system of the moth Manduca sexta, olfactory receptor neurons extend axons from the olfactory epithelium in the antenna into the brain. As they arrive at the brain, interactions with centrally derived glial cells cause axons to sort and fasciculate with other axons destined to innervate the same glomeruli. Here we report studies indicating that activation of the epidermal growth factor receptor (EGFR) is involved in axon ingrowth and targeting. Blocking the EGFR kinase domain pharmacologically leads to stalling of many axons in the sorting zone and nerve layer as well as abnormal axonal fasciculation in the sorting zone. We also find that neuroglian, an IgCAM known to activate the EGFR through homophilic interactions in other systems, is transiently present on olfactory receptor neuron axons and on glia during the critical stages of the sorting process. The neuroglian is resistant to extraction with Triton X-100 in the sorting zone and nerve layer, possibly indicating its stabilization by homophilic binding in these regions. Our results suggest a mechanism whereby neuroglian molecules on axons and possibly sorting zone glia bind homophilically, leading to activation of EGFRs, with subsequent effects on axon sorting, pathfinding, and extension, and glomerulus development. Copyright 2006 Wiley-Liss, Inc.

Activation of EGF Receptor Mediates Receptor Axon Sorting and Extension in the Developing Olfactory System of the Moth Manduca sexta

PubMed Central

Gibson, Nicholas J.; Tolbert, Leslie P.

2008-01-01

During development of the adult olfactory system of the moth Manduca sexta, olfactory receptor neurons extend axons from the olfactory epithelium in the antenna into the brain. As they arrive at the brain, interactions with centrally-derived glial cells cause axons to sort and fasciculate with other axons destined to innervate the same glomeruli. Here we report studies that indicate that activation of the epidermal growth factor receptor (EGFR) is involved in axon ingrowth and targeting. Blocking the EGFR kinase domain pharmacologically leads to stalling of many axons in the sorting zone and nerve layer, as well as abnormal axonal fasciculation in the sorting zone. We also find that neuroglian, an IgCAM known to activate the EGFR through homophilic interactions in other systems, is transiently present on olfactory receptor neuron axons and on glia during the critical stages of the sorting process. The neuroglian is resistant to extraction with Triton X-100 in the sorting zone and nerve layer, possibly indicating its stabilization by homophilic binding in these regions. Our results suggest a mechanism whereby neuroglian molecules on axons and possibly sorting zone glia bind homophilically, leading to activation of EGFRs with subsequent effects on axon sorting, pathfinding, and extension, and glomerulus development. PMID:16498681

Effect of staining and freezing media on sortability of stallion spermatozoa and their post-thaw viability after sex-sorting and cryopreservation.

PubMed

Clulow, J R; Buss, H; Evans, G; Sieme, H; Rath, D; Morris, L H A; Maxwell, W M C

2012-02-01

Sex-sorted, frozen-thawed stallion spermatozoa remain out of reach of commercial horse breeders because of the low efficiency of the sex-sorting process and unacceptable fertility rates after insemination. Two experiments were designed to test the effects of alternative staining and freezing media to improve the viability of sex-sorted frozen-thawed stallion spermatozoa. Experiment 1 compared two freezing media, INRA 82(®) and a modified lactose-ethylenediaminetetraacetic acid (EDTA), for the cryopreservation of sex-sorted stallion spermatozoa. No significant differences between the two freezing media could be identified, suggesting that both cryodiluents would be suitable for incorporation into a sex-preselection protocol for stallion spermatozoa. Experiment 2 compared Kenney's modified Tyrode's (KMT) and Sperm TALP (Sp-TALP) as the staining and incubation medium for stallion spermatozoa prior to sex-sorting. A significant increase in the percentage of acrosome-reacted spermatozoa occurred after staining and incubation in the clarified Sp-TALP compared with KMT. As no improvements in sorting rates were achieved using Sp-TALP, it was concluded that stallion sorting protocols could include KMT as the staining and incubation medium while either INRA 82(®) or lactose-EDTA could be employed as a cryodiluents. © 2011 Blackwell Verlag GmbH.

Sorted bedform pattern evolution: Persistence, destruction and self-organized intermittency

NASA Astrophysics Data System (ADS)

Goldstein, Evan B.; Murray, A. Brad; Coco, Giovanni

2011-12-01

We investigate the long-term evolution of inner continental shelf sorted bedform patterns. Numerical modeling suggests that a range of behaviors are possible, from pattern persistence to spatial-temporal intermittency. Sorted bedform persistence results from a robust sorting feedback that operates when the seabed features a sufficient concentration of coarse material. In the absence of storm events, pattern maturation processes such as defect dynamics and pattern migration tend to cause the burial of coarse material and excavation of fine material, leading to the fining of the active layer. Vertical sorting occurs until a critical state of active layer coarseness is reached. This critical state results in the local cessation of the sorting feedback, leading to a self-organized spatially intermittent pattern, a hallmark of observed sorted bedforms. Bedforms in shallow conditions and those subject to high wave climates may be temporally intermittent features as a result of increased wave orbital velocity during storms. Erosion, or deposition of bimodal sediment, similarly leads to a spatially intermittent pattern, with individual coarse domains exhibiting temporal intermittence. Recurring storm events cause coarsening of the seabed (strengthening the sorting feedback) and the development of large wavelength patterns. Cessation of storm events leads to the superposition of storm (large wavelength) and inter-storm (small wavelength) patterns and spatial heterogeneity of pattern modes.

A Sequence of Sorting Strategies.

ERIC Educational Resources Information Center

Duncan, David R.; Litwiller, Bonnie H.

1984-01-01

Describes eight increasingly sophisticated and efficient sorting algorithms including linear insertion, binary insertion, shellsort, bubble exchange, shakersort, quick sort, straight selection, and tree selection. Provides challenges for the reader and the student to program these efficiently. (JM)

UBE4B Protein Couples Ubiquitination and Sorting Machineries to Enable Epidermal Growth Factor Receptor (EGFR) Degradation*

PubMed Central

Sirisaengtaksin, Natalie; Gireud, Monica; Yan, Qing; Kubota, Yoshihisa; Meza, Denisse; Waymire, Jack C.; Zage, Peter E.; Bean, Andrew J.

2014-01-01

The signaling of plasma membrane proteins is tuned by internalization and sorting in the endocytic pathway prior to recycling or degradation in lysosomes. Ubiquitin modification allows recognition and association of cargo with endosomally associated protein complexes, enabling sorting of proteins to be degraded from those to be recycled. The mechanism that provides coordination between the cellular machineries that mediate ubiquitination and endosomal sorting is unknown. We report that the ubiquitin ligase UBE4B is recruited to endosomes in response to epidermal growth factor receptor (EGFR) activation by binding to Hrs, a key component of endosomal sorting complex required for transport (ESCRT) 0. We identify the EGFR as a substrate for UBE4B, establish UBE4B as a regulator of EGFR degradation, and describe a mechanism by which UBE4B regulates endosomal sorting, affecting cellular levels of the EGFR and its downstream signaling. We propose a model in which the coordinated action of UBE4B, ESCRT-0, and the deubiquitinating enzyme USP8 enable the endosomal sorting and lysosomal degradation of the EGFR. PMID:24344129

Statistical Characteristics of Single Sort of Grape Bulgarian Wines

NASA Astrophysics Data System (ADS)

Boyadzhiev, D.

2008-10-01

The aim of this paper is to evaluate the differences in the values of the 8 basic physicochemical indices of single sort of grape Bulgarian wines (white and red ones), obligatory for the standardization of ready production in the winery. Statistically significant differences in the values of various sorts and vintages are established and possibilities for identifying the sort and the vintage on the base of these indices by applying discriminant analysis are discussed.

Cloning of Plasmodium falciparum by single-cell sorting

PubMed Central

Miao, Jun; Li, Xiaolian; Cui, Liwang

2010-01-01

Malaria parasite cloning is traditionally carried out mainly by using the limiting dilution method, which is laborious, imprecise, and unable to distinguish multiply-infected RBCs. In this study, we used a parasite engineered to express green fluorescent protein (GFP) to evaluate a single-cell sorting method for rapidly cloning Plasmodium falciparum. By dividing a two dimensional scattergram from a cell sorter into 17 gates, we determined the parameters for isolating singly-infected erythrocytes and sorted them into individual cultures. Pre-gating of the engineered parasites for GFP allowed the isolation of almost 100% GFP-positive clones. Compared with the limiting dilution method, the number of parasite clones obtained by single-cell sorting was much higher. Molecular analyses showed that parasite isolates obtained by single-cell sorting were highly homogenous. This highly efficient single-cell sorting method should prove very useful for cloning both P. falciparum laboratory populations from genetic manipulation experiments and clinical samples. PMID:20435038

PhySortR: a fast, flexible tool for sorting phylogenetic trees in R.

PubMed

Stephens, Timothy G; Bhattacharya, Debashish; Ragan, Mark A; Chan, Cheong Xin

2016-01-01

A frequent bottleneck in interpreting phylogenomic output is the need to screen often thousands of trees for features of interest, particularly robust clades of specific taxa, as evidence of monophyletic relationship and/or reticulated evolution. Here we present PhySortR, a fast, flexible R package for classifying phylogenetic trees. Unlike existing utilities, PhySortR allows for identification of both exclusive and non-exclusive clades uniting the target taxa based on tip labels (i.e., leaves) on a tree, with customisable options to assess clades within the context of the whole tree. Using simulated and empirical datasets, we demonstrate the potential and scalability of PhySortR in analysis of thousands of phylogenetic trees without a priori assumption of tree-rooting, and in yielding readily interpretable trees that unambiguously satisfy the query. PhySortR is a command-line tool that is freely available and easily automatable.

Sortilin 1 knockout alters basal adipose glucose metabolism but not diet-induced obesity in mice.

PubMed

Li, Jibiao; Matye, David J; Wang, Yifeng; Li, Tiangang

2017-04-01

Sortilin 1 (Sort1) is a trafficking receptor that has been implicated in the regulation of plasma cholesterol in humans and mice. Here, we use metabolomics and hyperinsulinemic-euglycemic clamp approaches to obtain further understanding of the in vivo effects of Sort1 deletion on diet-induced obesity as well as on adipose lipid and glucose metabolism. Results show that Sort1 knockout (KO) does not affect Western diet-induced obesity nor adipose fatty acid and ceramide concentrations. Under the basal fasting state, chow-fed Sort1 KO mice have decreased adipose glycolytic metabolites, but Sort1 deletion does not affect insulin-stimulated tissue glucose uptake during the insulin clamp. These results suggest that Sort1 loss-of-function in vivo does not affect obesity development, but differentially modulates adipose glucose metabolism under fasting and insulin-stimulated states. © 2017 Federation of European Biochemical Societies.

Standard practice for cell sorting in a BSL-3 facility.

PubMed

Perfetto, Stephen P; Ambrozak, David R; Nguyen, Richard; Roederer, Mario; Koup, Richard A; Holmes, Kevin L

2011-01-01

Over the past decade, there has been a rapid growth in the number of BSL-3 and BSL-4 laboratories in the USA and an increase in demand for infectious cell sorting in BSL-3 laboratories. In 2007, the International Society for Advancement of Cytometry (ISAC) Biosafety Committee published standards for the sorting of unfixed cells and is an important resource for biosafety procedures when performing infectious cell sorting. Following a careful risk assessment, if it is determined that a cell sorter must be located within a BSL-3 laboratory, there are a variety of factors to be considered prior to the establishment of the laboratory. This chapter outlines procedures for infectious cell sorting in a BSL-3 environment to facilitate the establishment and safe operation of a BSL-3 cell sorting laboratory. Subjects covered include containment verification, remote operation, disinfection, personal protective equipment (PPE), and instrument-specific modifications for enhanced aerosol evacuation.

Standard Practice for Cell Sorting in a BSL-3 Facility

PubMed Central

Perfetto, Stephen P.; Ambrozak, David R.; Nguyen, Richard; Roederer, Mario; Koup, Richard A.; Holmes, Kevin L.

2016-01-01

Over the past decade, there has been a rapid growth in the number of BSL-3 and BSL-4 laboratories in the USA and an increase in demand for infectious cell sorting in BSL-3 laboratories. In 2007, the International Society for Advancement of Cytometry (ISAC) Biosafety Committee published standards for the sorting of unfixed cells and is an important resource for biosafety procedures when performing infectious cell sorting. Following a careful risk assessment, if it is determined that a cell sorter must be located within a BSL-3 laboratory, there are a variety of factors to be considered prior to the establishment of the laboratory. This chapter outlines procedures for infectious cell sorting in a BSL-3 environment to facilitate the establishment and safe operation of a BSL-3 cell sorting laboratory. Subjects covered include containment verification, remote operation, disinfection, personal protective equipment (PPE), and instrument-specific modifications for enhanced aerosol evacuation. PMID:21116997

Data parallel sorting for particle simulation

NASA Technical Reports Server (NTRS)

Dagum, Leonardo

1992-01-01

Sorting on a parallel architecture is a communications intensive event which can incur a high penalty in applications where it is required. In the case of particle simulation, only integer sorting is necessary, and sequential implementations easily attain the minimum performance bound of O (N) for N particles. Parallel implementations, however, have to cope with the parallel sorting problem which, in addition to incurring a heavy communications cost, can make the minimun performance bound difficult to attain. This paper demonstrates how the sorting problem in a particle simulation can be reduced to a merging problem, and describes an efficient data parallel algorithm to solve this merging problem in a particle simulation. The new algorithm is shown to be optimal under conditions usual for particle simulation, and its fieldwise implementation on the Connection Machine is analyzed in detail. The new algorithm is about four times faster than a fieldwise implementation of radix sort on the Connection Machine.

The interactive electrode localization utility: software for automatic sorting and labeling of intracranial subdural electrodes

PubMed Central

Tang, Wei; Peled, Noam; Vallejo, Deborah I.; Borzello, Mia; Dougherty, Darin D.; Eskandar, Emad N.; Widge, Alik S.; Cash, Sydney S.; Stufflebeam, Steven M.

2018-01-01

Purpose Existing methods for sorting, labeling, registering, and across-subject localization of electrodes in intracranial encephalography (iEEG) may involve laborious work requiring manual inspection of radiological images. Methods We describe a new open-source software package, the interactive electrode localization utility which presents a full pipeline for the registration, localization, and labeling of iEEG electrodes from CT and MR images. In addition, we describe a method to automatically sort and label electrodes from subdural grids of known geometry. Results We validated our software against manual inspection methods in twelve subjects undergoing iEEG for medically intractable epilepsy. Our algorithm for sorting and labeling performed correct identification on 96% of the electrodes. Conclusions The sorting and labeling methods we describe offer nearly perfect performance and the software package we have distributed may simplify the process of registering, sorting, labeling, and localizing subdural iEEG grid electrodes by manual inspection. PMID:27915398

OrbView-3 Initial On-Orbit Characterization

NASA Technical Reports Server (NTRS)

Ross, Kent; Blonski, Slawomir; Holekamp, Kara; Pagnutti, Mary; Zanoni, Vicki; Carver, David; Fendley, Debbie; Smith, Charles

2004-01-01

NASA at Stennis Space Center (SSC) established a Space Act Agreement with Orbital Sciences Corporation (OSC) and ORBIMAGE Inc. to collaborate on the characterization of the OrbView-3 system and its imagery products and to develop characterization techniques further. In accordance with the agreement, NASA performed an independent radiometric, spatial, and geopositional accuracy assessment of OrbView-3 imagery acquired before completion of the system's initial on-orbit checkout. OSC acquired OrbView-3 imagery over SSC from July 2003 through January 2004, and NASA collected ground reference information coincident with many of these acquisitions. After evaluating all acquisitions, NASA deemed two multispectral images and five panchromatic images useful for characterization. NASA then performed radiometric, spatial, and geopositional characterizations.

A Kalman Approach to Lunar Surface Navigation using Radiometric and Inertial Measurements

NASA Technical Reports Server (NTRS)

Chelmins, David T.; Welch, Bryan W.; Sands, O. Scott; Nguyen, Binh V.

2009-01-01

Future lunar missions supporting the NASA Vision for Space Exploration will rely on a surface navigation system to determine astronaut position, guide exploration, and return safely to the lunar habitat. In this report, we investigate one potential architecture for surface navigation, using an extended Kalman filter to integrate radiometric and inertial measurements. We present a possible infrastructure to support this technique, and we examine an approach to simulating navigational accuracy based on several different system configurations. The results show that position error can be reduced to 1 m after 5 min of processing, given two satellites, one surface communication terminal, and knowledge of the starting position to within 100 m.

Mass selective separation applied to radioisotopes of cesium: Mass selective applied to radioisotopes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dion, Michael; Eiden, Greg; Farmer, Orville

2016-07-22

A developed technique that uses the intrinsic mass-based separation capability of a quadrupole mass spectrometer has been used to resolve spectral radiometric interference of two isotopes of the same element. In this work the starting sample was a combination of 137Cs and 134Cs and was (activity) dominated by 137Cs and this methodology separated and “implanted” 134Cs that was later quantified for spectral features and ac- tivity with traditional radiometric techniques. This work demonstrated a 134Cs/137Cs activity ratio enhancement of >4 orders of magnitude and complete removal of 137Cs spectral features from the implanted target mass (i.e., 134).

The effect of spatial, spectral and radiometric factors on classification accuracy using thematic mapper data

NASA Technical Reports Server (NTRS)

Wrigley, R. C.; Acevedo, W.; Alexander, D.; Buis, J.; Card, D.

1984-01-01

An experiment of a factorial design was conducted to test the effects on classification accuracy of land cover types due to the improved spatial, spectral and radiometric characteristics of the Thematic Mapper (TM) in comparison to the Multispectral Scanner (MSS). High altitude aircraft scanner data from the Airborne Thematic Mapper instrument was acquired over central California in August, 1983 and used to simulate Thematic Mapper data as well as all combinations of the three characteristics for eight data sets in all. Results for the training sites (field center pixels) showed better classification accuracies for MSS spatial resolution, TM spectral bands and TM radiometry in order of importance.

High-precision radiometric tracking for planetary approach and encounter in the inner solar system

NASA Technical Reports Server (NTRS)

Christensen, C. S.; Thurman, S. W.; Davidson, J. M.; Finger, M. H.; Folkner, W. M.

1989-01-01

The benefits of improved radiometric tracking data have been studied for planetary approach within the inner Solar System using the Mars Rover Sample Return trajectory as a model. It was found that the benefit of improved data to approach and encounter navigation was highly dependent on the a priori uncertainties assumed for several non-estimated parameters, including those for frame-tie, Earth orientation, troposphere delay, and station locations. With these errors at their current levels, navigational performance was found to be insensitive to enhancements in data accuracy. However, when expected improvements in these errors are modeled, performance with current-accuracy data significantly improves, with substantial further improvements possible with enhancements in data accuracy.

Revised radiometric calibration technique for LANDSAT-4 Thematic Mapper data

NASA Technical Reports Server (NTRS)

Murphy, J.; Butlin, T.; Duff, P.; Fitzgerald, A.

1984-01-01

Depending on detector number, there are random fluctuations in the background level for spectral band 1 of magnitudes ranging from 2 to 3.5 digital numbers (DN). Similar variability is observed in all the other reflective bands, but with smaller magnitude in the range 0.5 to 2.5 DN. Observations of background reference levels show that line dependent variations in raw TM image data and in the associated calibration data can be measured and corrected within an operational environment by applying simple offset corrections on a line-by-line basis. The radiometric calibration procedure defined by the Canadian Center for Remote Sensing was revised accordingly in order to prevent striping in the output product.

GIFTS SM EDU Radiometric and Spectral Calibrations

NASA Technical Reports Server (NTRS)

Tian, J.; Reisse, R. a.; Johnson, D. G.; Gazarik, J. J.

2007-01-01

The Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS) Sensor Module (SM) Engineering Demonstration Unit (EDU) is a high resolution spectral imager designed to measure infrared (IR) radiance using a Fourier transform spectrometer (FTS). The GIFTS instrument gathers measurements across the long-wave IR (LWIR), short/mid-wave IR (SMWIR), and visible spectral bands. The raw interferogram measurements are radiometrically and spectrally calibrated to produce radiance spectra, which are further processed to obtain atmospheric profiles via retrieval algorithms. This paper describes the processing algorithms involved in the calibration. The calibration procedures can be subdivided into three categories: the pre-calibration stage, the calibration stage, and finally, the post-calibration stage. Detailed derivations for each stage are presented in this paper.

Ar-Ar Dating of Martian Chassignites, NWA2737 and Chassigny, and Nakhlite MIL03346

NASA Technical Reports Server (NTRS)

Bogard, D. D.; Garrison, D. H.

2006-01-01

Until recently only three nakhlites and one chassignite had been identified among martian meteorites. These four exhibit very similar radiometric ages and cosmic ray exposure (CRE) ages, indicating that they may have derived from a common location on Mars and were ejected into space by a single impact. This situation is quite different from that of martian shergottites, which exhibit a range of radiometric ages and CRE ages (1). Recently, several new nakhlites and a new martian dunite (NWA2737) have been recognized. Here we report our results of Ar-39-Ar-40 dating for the MIL03346 nakhlite and the NWA2737 "chassignite", along with new results on Chassigny.

An intercomparison of longwave measurements by ERBE radiometers on the NOAA-9 and ERBS satellites

NASA Technical Reports Server (NTRS)

House, Frederick B.

1989-01-01

Two instrument modules of each satellite on which the Earth Radiation Budget Experiment (ERBE) is orbiting observe components of the earth radiation budget with three different scales of earth view. An intercomparison of longwave measurements by these instruments provides relative information concerning radiometric performance at satellite altitude, techniques of estimating upwelling exitances, and an end-to-end evaluation of the data processing system. Results indicate that the ERBE radiometers are mildly sensitive to varying thermal loads from the spacecraft and/or the earth-space environment. Radiometric variations at the satellite and methods of data interpretation contribute about equally to the uncertainty of radiant exitances from the earth.

Evaluation of S190A radiometric exposure test data

NASA Technical Reports Server (NTRS)

Lockwood, H. E.; Goodding, R. A.

1974-01-01

The S190A preflight radiometric exposure test data generated as part of preflight and system test of KM-002 Sequence 29 on flight camera S/N 002 was analyzed. The analysis was to determine camera system transmission using available data which included: (1) films exposed to a calibrated light source subject; (2) filter transmission data; (3) calibrated light source data; (4) density vs. log10 exposure curves for the films; and (5) spectral sensitometric data for the films. The procedure used is outlined, and includes the data and a transmission matrix as a function of field position for nine measured points on each station-film-filter-aperture-shutter speed combination.

Study of the character of the time dependence of the ratio of signals in the IR and visible channels of a radiometric apparatus when fragments of space junk are observed

NASA Astrophysics Data System (ADS)

Pavlov, N. I.; Él'Ts, E. É.

2006-01-01

A more accurate expression is derived for determining the specific load of fragments of space junk via the time dependence of the ratio of signals in the IR and visible channels of on-board radiometric observation apparatus. Results are presented of a calculation of the time behavior of this ratio when aluminum and plastic debris is observed on near-earth orbits. The cases considered here involve constant heating of the debris by solar radiation and the variation of this heating according to a harmonic law because the debris rotates around its center of mass.

Microwave radiometric aircraft observations of the Fabry-Perot interference fringes of an ice-water system

NASA Technical Reports Server (NTRS)

Harrington, R. F.; Swift, C. T.; Fedors, J. C.

1980-01-01

Airborne stepped-frequency microwave radiometer (SFMR) observations of the Fabry-Perot interference fringes of ice-water systems are discussed. The microwave emissivity at normal incidence of a smooth layered dielectric medium over a semi-infinite dielectric medium is examined for the case of ice over water as a function of ice thickness and attenuation coefficient, and the presence of quarter-wavelength oscillations in emissivity as the ice thickness and frequency are varied is pointed out. Experimental observations of pronounced quarter-wavelength oscillations in radiometric brightness temperature due to the Fabry-Perot interference fringes over smooth sea ice and lake ice varying in roughness as the radiometer frequencies were scanned are then presented.

The importance and attainment of accurate absolute radiometric calibration

NASA Technical Reports Server (NTRS)

Slater, P. N.

1984-01-01

The importance of accurate absolute radiometric calibration is discussed by reference to the needs of those wishing to validate or use models describing the interaction of electromagnetic radiation with the atmosphere and earth surface features. The in-flight calibration methods used for the Landsat Thematic Mapper (TM) and the Systeme Probatoire d'Observation de la Terre, Haute Resolution visible (SPOT/HRV) systems are described and their limitations discussed. The questionable stability of in-flight absolute calibration methods suggests the use of a radiative transfer program to predict the apparent radiance, at the entrance pupil of the sensor, of a ground site of measured reflectance imaged through a well characterized atmosphere. The uncertainties of such a method are discussed.

Temperature measurements behind reflected shock waves in air. [radiometric measurement of gas temperature in self-absorbing gas flow

NASA Technical Reports Server (NTRS)

Bader, J. B.; Nerem, R. M.; Dann, J. B.; Culp, M. A.

1972-01-01

A radiometric method for the measurement of gas temperature in self-absorbing gases has been applied in the study of shock tube generated flows. This method involves making two absolute intensity measurements at identical wavelengths, but for two different pathlengths in the same gas sample. Experimental results are presented for reflected shock waves in air at conditions corresponding to incident shock velocities from 7 to 10 km/s and an initial driven tube pressure of 1 torr. These results indicate that, with this technique, temperature measurements with an accuracy of + or - 5 percent can be carried out. The results also suggest certain facility related problems.

A calibration method of infrared LVF based spectroradiometer

NASA Astrophysics Data System (ADS)

Liu, Jiaqing; Han, Shunli; Liu, Lei; Hu, Dexin

2017-10-01

In this paper, a calibration method of LVF-based spectroradiometer is summarize, including spectral calibration and radiometric calibration. The spectral calibration process as follow: first, the relationship between stepping motor's step number and transmission wavelength is derivative by theoretical calculation, including a non-linearity correction of LVF;second, a line-to-line method was used to corrected the theoretical wavelength; Finally, the 3.39 μm and 10.69 μm laser is used for spectral calibration validation, show the sought 0.1% accuracy or better is achieved.A new sub-region multi-point calibration method is used for radiometric calibration to improving accuracy, results show the sought 1% accuracy or better is achieved.

MODIS Solar Diffuser: Modelled and Actual Performance

NASA Technical Reports Server (NTRS)

Waluschka, Eugene; Xiong, Xiao-Xiong; Esposito, Joe; Wang, Xin-Dong; Krebs, Carolyn (Technical Monitor)

2001-01-01

The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument's solar diffuser is used in its radiometric calibration for the reflective solar bands (VIS, NTR, and SWIR) ranging from 0.41 to 2.1 micron. The sun illuminates the solar diffuser either directly or through a attenuation screen. The attenuation screen consists of a regular array of pin holes. The attenuated illumination pattern on the solar diffuser is not uniform, but consists of a multitude of pin-hole images of the sun. This non-uniform illumination produces small, but noticeable radiometric effects. A description of the computer model used to simulate the effects of the attenuation screen is given and the predictions of the model are compared with actual, on-orbit, calibration measurements.

Impact of respiratory-correlated CT sorting algorithms on the choice of margin definition for free-breathing lung radiotherapy treatments.

PubMed

Thengumpallil, Sheeba; Germond, Jean-François; Bourhis, Jean; Bochud, François; Moeckli, Raphaël

2016-06-01

To investigate the impact of Toshiba phase- and amplitude-sorting algorithms on the margin strategies for free-breathing lung radiotherapy treatments in the presence of breathing variations. 4D CT of a sphere inside a dynamic thorax phantom was acquired. The 4D CT was reconstructed according to the phase- and amplitude-sorting algorithms. The phantom was moved by reproducing amplitude, frequency, and a mix of amplitude and frequency variations. Artefact analysis was performed for Mid-Ventilation and ITV-based strategies on the images reconstructed by phase- and amplitude-sorting algorithms. The target volume deviation was assessed by comparing the target volume acquired during irregular motion to the volume acquired during regular motion. The amplitude-sorting algorithm shows reduced artefacts for only amplitude variations while the phase-sorting algorithm for only frequency variations. For amplitude and frequency variations, both algorithms perform similarly. Most of the artefacts are blurring and incomplete structures. We found larger artefacts and volume differences for the Mid-Ventilation with respect to the ITV strategy, resulting in a higher relative difference of the surface distortion value which ranges between maximum 14.6% and minimum 4.1%. The amplitude- is superior to the phase-sorting algorithm in the reduction of motion artefacts for amplitude variations while phase-sorting for frequency variations. A proper choice of 4D CT sorting algorithm is important in order to reduce motion artefacts, especially if Mid-Ventilation strategy is used. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Efficient sampling of parsimonious inversion histories with application to genome rearrangement in Yersinia.

PubMed

Miklós, István; Darling, Aaron E

2009-06-22

Inversions are among the most common mutations acting on the order and orientation of genes in a genome, and polynomial-time algorithms exist to obtain a minimal length series of inversions that transform one genome arrangement to another. However, the minimum length series of inversions (the optimal sorting path) is often not unique as many such optimal sorting paths exist. If we assume that all optimal sorting paths are equally likely, then statistical inference on genome arrangement history must account for all such sorting paths and not just a single estimate. No deterministic polynomial algorithm is known to count the number of optimal sorting paths nor sample from the uniform distribution of optimal sorting paths. Here, we propose a stochastic method that uniformly samples the set of all optimal sorting paths. Our method uses a novel formulation of parallel Markov chain Monte Carlo. In practice, our method can quickly estimate the total number of optimal sorting paths. We introduce a variant of our approach in which short inversions are modeled to be more likely, and we show how the method can be used to estimate the distribution of inversion lengths and breakpoint usage in pathogenic Yersinia pestis. The proposed method has been implemented in a program called "MC4Inversion." We draw comparison of MC4Inversion to the sampler implemented in BADGER and a previously described importance sampling (IS) technique. We find that on high-divergence data sets, MC4Inversion finds more optimal sorting paths per second than BADGER and the IS technique and simultaneously avoids bias inherent in the IS technique.

Size-based cell sorting with a resistive pulse sensor and an electromagnetic pump in a microfluidic chip.

PubMed

Song, Yongxin; Li, Mengqi; Pan, Xinxiang; Wang, Qi; Li, Dongqing

2015-02-01

An electrokinetic microfluidic chip is developed to detect and sort target cells by size from human blood samples. Target-cell detection is achieved by a differential resistive pulse sensor (RPS) based on the size difference between the target cell and other cells. Once a target cell is detected, the detected RPS signal will automatically actuate an electromagnetic pump built in a microchannel to push the target cell into a collecting channel. This method was applied to automatically detect and sort A549 cells and T-lymphocytes from a peripheral fingertip blood sample. The viability of A549 cells sorted in the collecting well was verified by Hoechst33342 and propidium iodide staining. The results show that as many as 100 target cells per minute can be sorted out from the sample solution and thus is particularly suitable for sorting very rare target cells, such as circulating tumor cells. The actuation of the electromagnetic valve has no influence on RPS cell detection and the consequent cell-sorting process. The viability of the collected A549 cell is not impacted by the applied electric field when the cell passes the RPS detection area. The device described in this article is simple, automatic, and label-free and has wide applications in size-based rare target cell sorting for medical diagnostics. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Microfluidic droplet sorting using integrated bilayer micro-valves

NASA Astrophysics Data System (ADS)

Chen, Yuncong; Tian, Yang; Xu, Zhen; Wang, Xinran; Yu, Sicong; Dong, Liang

2016-10-01

This paper reports on a microfluidic device capable of sorting microfluidic droplets utilizing conventional bilayer pneumatic micro-valves as sorting controllers. The device consists of two micro-valves placed symmetrically on two sides of a sorting area, each on top of a branching channel at an inclined angle with respect to the main channel. Changes in transmitted light intensity, induced by varying light absorbance by each droplet, are used to divert the droplet from the sorting area into one of the three outlet channels. When no valve is activated, the droplet flows into the outlet channel in the direction of the main channel. When one of the valves is triggered, the flexible membrane of valve will first be deflected. Once the droplet leaves the detection point, the deflected membrane will immediately return to its default flattened position, thereby exerting a drawing pressure on the droplet and deviating it from its original streamline to the outlet on the same side as the valve. This sorting method will be particularly suitable for numerous large-scale integrated microfluidic systems, where pneumatic micro-valves are already used. Only few structural modifications are needed to achieve droplet sorting capabilities in these systems. Due to the mechanical nature of diverting energy applied to droplets, the proposed sorting method may induce only minimal interference to biological species or microorganisms encapsulated inside the droplets that may accompany electrical, optical and magnetic-based techniques.

Airborne lidar/radiometric measurements of cirrus cloud parameters and their application to LOWTRAN radiance evaluations

NASA Technical Reports Server (NTRS)

Uthe, Edward E.

1990-01-01

SRI has assembled an airborne lidar/radiometric instrumentation suite for mapping cirrus cloud distribution and analyzing cirrus cloud optical properties. Operation of upward viewing infrared radiometers from an airborne platform provides the optimum method of measuring high altitude cold cloud radiative properties with minimum interference from the thermal emission by the earth's surface and lower atmospheric components. Airborne installed sensors can also operate over large regional areas including water, urban, and mountain surfaces and above lower atmospheric convective clouds and haze layers. Currently available sensors installed on the SRI Queen Air aircraft are illustrated. Lidar and radiometric data records are processed for real time viewing on a color video screen. A cirrus cloud data example is presented as a black and white reproduction of a color display of data at the aircraft altitude of 12,000 ft, the 8 to 14 micron atmospheric radiation background was equivalent to a blackbody temperature of about -60 C and, therefore, the radiometer did not respond strongly to low density cirrus cloud concentrations detected by the lidar. Cloud blackbody temperatures (observed by radiometer) are shown plotted against midcloud temperatures (derived from lidar observed cloud heights and supporting temperature profiles) for data collected on 30 June and 28 July.

Modeling the Radiance of the Moon for On-orbit Calibration

USGS Publications Warehouse

Stone, T.C.; Kieffer, H.H.; Becker, K.J.; ,

2003-01-01

The RObotic Lunar Observatory (ROLO) project has developed radiometric models of the Moon for disk-integrated irradiance and spatially resolved radiance. Although the brightness of the Moon varies spatially and with complex dependencies upon illumination and viewing geometry, the surface photometric properties are extremely stable, and therefore potentially knowable to high accuracy. The ROLO project has acquired 5+ years of spatially resolved lunar images in 23 VNIR and 9 SWIR filter bands at phase angles up to 90??. These images are calibrated to exoatmospheric radiance using nightly stellar observations in a band-coupled extinction algorithm and a radiometric scale based upon observations of the star Vega. An effort is currently underway to establish an absolute scale with direct traceability to NIST radiometric standards. The ROLO radiance model performs linear fitting of the spatially resolved lunar image data on an individual pixel basis. The results are radiance images directly comparable to spacecraft observations of the Moon. Model-generated radiance images have been produced for the ASTER lunar view conducted on 14 April 2003. The radiance model is still experimental - simplified photometric functions have been used, and initial results show evidence of computational instabilities, particularly at the lunar poles. The ROLO lunar image dataset is unique and extensive and presents opportunities for development of novel approaches to lunar photometric modeling.

NURE aerial gamma-ray and magnetic-reconnaissance survey portions of New Mexico, Arizona, and Texas. Volume I. Instrumentation and data reduction. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

As part of the Department of Energy (DOE) National Uranium Resource Evaluation Program, a rotary-wing high sensitivity radiometric and magnetic survey was flown covering portions of the State of New Mexico, Arizona and Texas. The survey encompassed six 1:250,000 scale quadrangles, Holbrook, El Paso, Las Cruces, Carlsbad, Fort Sumner and Roswell. The survey was flown with a Sikorsky S58T helicopter equipped with a high sensitivity gamma ray spectrometer which was calibrated at the DOE calibration facilities at Walker Field in Grand Junction, Colorado, and the Dynamic Test Range at Lake Mead, Arizona. The radiometric data were processed to compensate formore » Compton scattering effects and altitude variations. The data were normalized to 400 feet terrain clearance. The reduced data is presented in the form of stacked profiles, standard deviation anomaly plots, histogram plots and microfiche listings. The results of the geologic interpretation of the radiometric data together with the profiles, anomaly maps and histograms are presented in the individual quadrangle reports. The survey was awarded to LKB Resources, Inc. which completed the data acquisition. In April, 1980 Carson Helicopters, Inc. and Carson Geoscience Company agreed to manage the project and complete delivery of this final report.« less

Analysis of AIRS and IASI System Performance Under Clear and Cloudy Conditions

NASA Technical Reports Server (NTRS)

Aumann, Hartmut H.; Strow, L. Larrabee

2010-01-01

The radiometric and spectral system performance of space-borne infrared radiometers is generally specified and analyzed under strictly cloud-free, spatially uniform and warm conditions, with the assumption that the observed performance applies to the full dynamic range under clear and cloudy conditions and that random noise cancels for the evaluation of the radiometric accuracy. Such clear conditions are found in only one percent of the data. Ninety nine percent of the data include clouds, which produce spatially highly non-uniform scenes with 11 micrometers window brightness temperatures as low as 200K. We use AIRS and IASI radiance spectra to compare system performance under clear and a wide range of cloudy conditions. Although the two instruments are in polar orbits, with the ascending nodes separated by four hours, daily averages already reveal surprisingly similar measurements. The AIRS and IASI radiometric performance based on the mean of large numbers of observation is comparable and agrees within 200 mK over a wide range of temperatures. There are also some unexpected differences at the 200 -500 mK level, which are of significance for climate applications. The results were verified with data from July 2007 through January 2010, but many can already be gleaned from the analysis of a single day of data.

The First SIMBIOS Radiometric Intercomparison (SIMRIC-1), April-September 2001

NASA Technical Reports Server (NTRS)

Meister, Gerhard; Abel, Peter; McClain, Charles; Barnes, Robert; Fargion, Giulietta; Cooper, John; Davis, Curtiss; Korwan, Daniel; Godin, Mike; Maffione, Robert

2002-01-01

This report describes the first SIMBIOS (Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies) Radiometric Intercomparison (SIMRIC-1). The purpose of the SIMRIC-1 is to ensure a common radiometric scale of the calibration facilities that are engaged in calibrating in situ radiometers used for ocean color related research and to document the calibration procedures and protocols. SIMBIOS staff visited the seven participating laboratories for at least two days each. The SeaWiFS Transfer Radiometer SXR-II measured the calibration radiances produced in the laboratories. The measured radiances were compared with the radiances expected by the laboratories. Typically, the measured radiances were higher than the expected radiances by 0 to 2%. This level of agreement is satisfactory. Several issues were identified, where the calibration protocols need to be improved, especially the reflectance calibration of the reference plaques and the distance correction when using the irradiance standards at distances greater than the 50 cm. The responsivity of the SXR-II changed between 0.3% (channel 6) and 1.6% (channel 2) from December 2000 to December 2001. Monitoring the SXR-II with a portable light source showed a linear drift of the calibration, except for channel 1, where a 2% drop occurred in summer.

Reduction of Radiometric Miscalibration—Applications to Pushbroom Sensors

PubMed Central

Rogaß, Christian; Spengler, Daniel; Bochow, Mathias; Segl, Karl; Lausch, Angela; Doktor, Daniel; Roessner, Sigrid; Behling, Robert; Wetzel, Hans-Ulrich; Kaufmann, Hermann

2011-01-01

The analysis of hyperspectral images is an important task in Remote Sensing. Foregoing radiometric calibration results in the assignment of incident electromagnetic radiation to digital numbers and reduces the striping caused by slightly different responses of the pixel detectors. However, due to uncertainties in the calibration some striping remains. This publication presents a new reduction framework that efficiently reduces linear and nonlinear miscalibrations by an image-driven, radiometric recalibration and rescaling. The proposed framework—Reduction Of Miscalibration Effects (ROME)—considering spectral and spatial probability distributions, is constrained by specific minimisation and maximisation principles and incorporates image processing techniques such as Minkowski metrics and convolution. To objectively evaluate the performance of the new approach, the technique was applied to a variety of commonly used image examples and to one simulated and miscalibrated EnMAP (Environmental Mapping and Analysis Program) scene. Other examples consist of miscalibrated AISA/Eagle VNIR (Visible and Near Infrared) and Hawk SWIR (Short Wave Infrared) scenes of rural areas of the region Fichtwald in Germany and Hyperion scenes of the Jalal-Abad district in Southern Kyrgyzstan. Recovery rates of approximately 97% for linear and approximately 94% for nonlinear miscalibrated data were achieved, clearly demonstrating the benefits of the new approach and its potential for broad applicability to miscalibrated pushbroom sensor data. PMID:22163960

Using Landsat Surface Reflectance Data as a Reference Target for Multiswath Hyperspectral Data Collected Over Mixed Agricultural Rangeland Areas

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCann, Cooper; Repasky, Kevin S.; Morin, Mikindra

Low-cost flight-based hyperspectral imaging systems have the potential to provide important information for ecosystem and environmental studies as well as aide in land management. To realize this potential, methods must be developed to provide large-area surface reflectance data allowing for temporal data sets at the mesoscale. This paper describes a bootstrap method of producing a large-area, radiometrically referenced hyperspectral data set using the Landsat surface reflectance (LaSRC) data product as a reference target. The bootstrap method uses standard hyperspectral processing techniques that are extended to remove uneven illumination conditions between flight passes, allowing for radiometrically self-consistent data after mosaicking. Throughmore » selective spectral and spatial resampling, LaSRC data are used as a radiometric reference target. Advantages of the bootstrap method include the need for minimal site access, no ancillary instrumentation, and automated data processing. Data from two hyperspectral flights over the same managed agricultural and unmanaged range land covering approximately 5.8 km 2 acquired on June 21, 2014 and June 24, 2015 are presented. As a result, data from a flight over agricultural land collected on June 6, 2016 are compared with concurrently collected ground-based reflectance spectra as a means of validation.« less

Landsat-7 ETM+ radiometric calibration status

USGS Publications Warehouse

Barsi, Julia A.; Markham, Brian L.; Czapla-Myers, J. S.; Helder, Dennis L.; Hook, Simon; Schott, John R.; Haque, Md. Obaidul

2016-01-01

Now in its 17th year of operation, the Enhanced Thematic Mapper + (ETM+), on board the Landsat-7 satellite, continues to systematically acquire imagery of the Earth to add to the 40+ year archive of Landsat data. Characterization of the ETM+ on-orbit radiometric performance has been on-going since its launch in 1999. The radiometric calibration of the reflective bands is still monitored using on-board calibration devices, though the Pseudo-Invariant Calibration Sites (PICS) method has proven to be an effective tool as well. The calibration gains were updated in April 2013 based primarily on PICS results, which corrected for a change of as much as -0.2%/year degradation in the worst case bands. A new comparison with the SADE database of PICS results indicates no additional degradation in the updated calibration. PICS data are still being tracked though the recent trends are not well understood. The thermal band calibration was updated last in October 2013 based on a continued calibration effort by NASA/Jet Propulsion Lab and Rochester Institute of Technology. The update accounted for a 0.036 W/m2 sr μm or 0.26K at 300K bias error. The updated lifetime trend is now stable to within +/- 0.4K.

Radiometric Survey in Western Afghanistan: A Website for Distribution of Data

USGS Publications Warehouse

Sweeney, Ronald E.; Kucks, Robert P.; Hill, Patricia L.; Finn, Carol A.

2007-01-01

Radiometric (uranium content, thorium content, potassium content, and gamma-ray intensity) and related data were digitized from radiometric and survey route location maps of western Afghanistan published in 1976. The uranium content data were digitized along contour lines from 33 maps in a series entitled 'Map of Uranium (Radium) Contents of Afghanistan (Western Area),' compiled by V. N. Kirsanov and R. S. Dershimanov. The thorium content data were digitized along contour lines from 33 maps in a series entitled 'Map of Thorium Contents of Afghanistan (Western Area),' compiled by V. N. Kirsanov and R. S. Dershimanov. The potassium content data were digitized along contour lines from 33 maps in a series entitled 'Map of Potassium Contents of Afghanistan (Western Area),' compiled by V. N. Kirsanov and R. S. Dershimanov. The gamma-ray intensity data were digitized along contour lines from 33 maps in a series entitled 'Map of Gamma-Field of Afghanistan (Western Area),' compiled by V. N. Kirsanov and R. S. Dershimanov. The survey route location data were digitized along flight-lines located on 33 maps in a series entitled 'Survey Routes Location and Contours of Flight Equal Altitudes. Western Area of Afghanistan,' compiled by Z. A. Alpatova, V. G. Kurnosov, and F. A. Grebneva.

Using Landsat Surface Reflectance Data as a Reference Target for Multiswath Hyperspectral Data Collected Over Mixed Agricultural Rangeland Areas

DOE PAGES

McCann, Cooper; Repasky, Kevin S.; Morin, Mikindra; ...

2017-07-25

Low-cost flight-based hyperspectral imaging systems have the potential to provide important information for ecosystem and environmental studies as well as aide in land management. To realize this potential, methods must be developed to provide large-area surface reflectance data allowing for temporal data sets at the mesoscale. This paper describes a bootstrap method of producing a large-area, radiometrically referenced hyperspectral data set using the Landsat surface reflectance (LaSRC) data product as a reference target. The bootstrap method uses standard hyperspectral processing techniques that are extended to remove uneven illumination conditions between flight passes, allowing for radiometrically self-consistent data after mosaicking. Throughmore » selective spectral and spatial resampling, LaSRC data are used as a radiometric reference target. Advantages of the bootstrap method include the need for minimal site access, no ancillary instrumentation, and automated data processing. Data from two hyperspectral flights over the same managed agricultural and unmanaged range land covering approximately 5.8 km 2 acquired on June 21, 2014 and June 24, 2015 are presented. As a result, data from a flight over agricultural land collected on June 6, 2016 are compared with concurrently collected ground-based reflectance spectra as a means of validation.« less

Transmittance Measurement of a Heliostat Facility used in the Preflight Radiometric Calibration of Earth-Observing Sensors

NASA Technical Reports Server (NTRS)

Czapla-Myers, J.; Thome, K.; Anderson, N.; McCorkel, J.; Leisso, N.; Good, W.; Collins, S.

2009-01-01

Ball Aerospace and Technologies Corporation in Boulder, Colorado, has developed a heliostat facility that will be used to determine the preflight radiometric calibration of Earth-observing sensors that operate in the solar-reflective regime. While automatically tracking the Sun, the heliostat directs the solar beam inside a thermal vacuum chamber, where the sensor under test resides. The main advantage to using the Sun as the illumination source for preflight radiometric calibration is because it will also be the source of illumination when the sensor is in flight. This minimizes errors in the pre- and post-launch calibration due to spectral mismatches. It also allows the instrument under test to operate at irradiance values similar to those on orbit. The Remote Sensing Group at the University of Arizona measured the transmittance of the heliostat facility using three methods, the first of which is a relative measurement made using a hyperspectral portable spectroradiometer and well-calibrated reference panel. The second method is also a relative measurement, and uses a 12-channel automated solar radiometer. The final method is an absolute measurement using a hyperspectral spectroradiometer and reference panel combination, where the spectroradiometer is calibrated on site using a solar-radiation-based calibration.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carbone, L.; Ciani, G.; Dolesi, R.

The low frequency sensitivity of space-borne gravitational wave observatories will depend critically on the geodesic purity of the trajectories of orbiting test masses. Fluctuations in the temperature difference across the enclosure surrounding the free-falling test mass can produce noisy forces through several processes, including the radiometric effect, radiation pressure, and outgassing. We present here a detailed experimental investigation of thermal gradient-induced forces for the Laser Interferometer Space Antenna (LISA) gravitational wave mission and the LISA Pathfinder, employing high resolution torsion pendulum measurements of the torque on a LISA-like test mass suspended inside a prototype of the LISA gravitational reference sensormore » that will surround the test mass in orbit. The measurement campaign, accompanied by numerical simulations of the radiometric and radiation pressure effects, allows a more accurate and representative characterization of thermal-gradient forces in the specific geometry and environment relevant to LISA free-fall. The pressure dependence of the measured torques allows clear identification of the radiometric effect, in quantitative agreement with the model developed. In the limit of zero gas pressure, the measurements are most likely dominated by outgassing, but at a low level that does not threaten the current LISA noise estimate, which assumes a maximum net force per degree of temperature difference of 100(pN/K) for the overall thermal gradient-induced effects.« less

Algorithm for automatic image dodging of unmanned aerial vehicle images using two-dimensional radiometric spatial attributes

NASA Astrophysics Data System (ADS)

Li, Wenzhuo; Sun, Kaimin; Li, Deren; Bai, Ting

2016-07-01

Unmanned aerial vehicle (UAV) remote sensing technology has come into wide use in recent years. The poor stability of the UAV platform, however, produces more inconsistencies in hue and illumination among UAV images than other more stable platforms. Image dodging is a process used to reduce these inconsistencies caused by different imaging conditions. We propose an algorithm for automatic image dodging of UAV images using two-dimensional radiometric spatial attributes. We use object-level image smoothing to smooth foreground objects in images and acquire an overall reference background image by relative radiometric correction. We apply the Contourlet transform to separate high- and low-frequency sections for every single image, and replace the low-frequency section with the low-frequency section extracted from the corresponding region in the overall reference background image. We apply the inverse Contourlet transform to reconstruct the final dodged images. In this process, a single image must be split into reasonable block sizes with overlaps due to large pixel size. Experimental mosaic results show that our proposed method reduces the uneven distribution of hue and illumination. Moreover, it effectively eliminates dark-bright interstrip effects caused by shadows and vignetting in UAV images while maximally protecting image texture information.

Radiometric and Geometric Accuracy Analysis of Rasat Pan Imagery

NASA Astrophysics Data System (ADS)

Kocaman, S.; Yalcin, I.; Guler, M.

2016-06-01

RASAT is the second Turkish Earth Observation satellite which was launched in 2011. It operates with pushbroom principle and acquires panchromatic and MS images with 7.5 m and 15 m resolutions, respectively. The swath width of the sensor is 30 km. The main aim of this study is to analyse the radiometric and geometric quality of RASAT images. A systematic validation approach for the RASAT imagery and its products is being applied. RASAT image pair acquired over Kesan city in Edirne province of Turkey are used for the investigations. The raw RASAT data (L0) are processed by Turkish Space Agency (TUBITAK-UZAY) to produce higher level image products. The image products include radiometrically processed (L1), georeferenced (L2) and orthorectified (L3) data, as well as pansharpened images. The image quality assessments include visual inspections, noise, MTF and histogram analyses. The geometric accuracy assessment results are only preliminary and the assessment is performed using the raw images. The geometric accuracy potential is investigated using 3D ground control points extracted from road intersections, which were measured manually in stereo from aerial images with 20 cm resolution and accuracy. The initial results of the study, which were performed using one RASAT panchromatic image pair, are presented in this paper.

Radiometric cross calibration of Landsat 8 Operational Land Imager (OLI) and Landsat 7 Enhanced Thematic Mapper Plus (ETM+)

USGS Publications Warehouse

Mishra, Nischal; Haque, Md. Obaidul; Leigh, Larry; Aaron, David; Helder, Dennis; Markham, Brian L

2014-01-01

This study evaluates the radiometric consistency between Landsat-8 Operational Land Imager (OLI) and Landsat 7 Enhanced Thematic Mapper Plus (ETM+) using cross calibration techniques. Two approaches are used, one based on cross calibration between the two sensors using simultaneous image pairs, acquired during an underfly event on 29–30 March 2013. The other approach is based on using time series of image statistics acquired by these two sensors over the Libya 4 pseudo invariant calibration site (PICS) (+28.55°N, +23.39°E). Analyses from these approaches show that the reflectance calibration of OLI is generally within ±3% of the ETM+ radiance calibration for all the reflective bands from visible to short wave infrared regions when the ChKur solar spectrum is used to convert the ETM+ radiance to reflectance. Similar results are obtained comparing the OLI radiance calibration directly with the ETM+ radiance calibration and the results in these two different physical units (radiance and reflectance) agree to within ±2% for all the analogous bands. These results will also be useful to tie all the Landsat heritage sensors from Landsat 1 MultiSpectral Scanner (MSS) through Landsat-8 OLI to a consistent radiometric scale.

The Global Precipitation Measurement (GPM) Microwave Imager (GMI): Instrument Overview and Early On-Orbit Performance

NASA Technical Reports Server (NTRS)

Draper, David W.; Newell, David A.; Wentz, Frank J.; Krimchansky, Sergey; Jackson, Gail

2015-01-01

The Global Precipitation Measurement (GPM) mission is an international satellite mission that uses measurements from an advanced radar/radiometer system on a core observatory as reference standards to unify and advance precipitation estimates made by a constellation of research and operational microwave sensors. The GPM core observatory was launched on February 27, 2014 at 18:37 UT in a 65? inclination nonsun-synchronous orbit. GPM focuses on precipitation as a key component of the Earth's water and energy cycle, and has the capability to provide near-real-time observations for tracking severe weather events, monitoring freshwater resources, and other societal applications. The GPM microwave imager (GMI) on the core observatory provides the direct link to the constellation radiometer sensors, which fly mainly in polar orbits. The GMI sensitivity, accuracy, and stability play a crucial role in unifying the measurements from the GPM constellation of satellites. The instrument has exhibited highly stable operations through the duration of the calibration/validation period. This paper provides an overview of the GMI instrument and a report of early on-orbit commissioning activities. It discusses the on-orbit radiometric sensitivity, absolute calibration accuracy, and stability for each radiometric channel. Index Terms-Calibration accuracy, passive microwave remote sensing, radiometric sensitivity.

THEMIS Images as Art #18

NASA Technical Reports Server (NTRS)

2004-01-01

Released 25 February 2004

Humanity is a very visual species. We rely on our eyes to tell us what is going on in the world around us. Put any image in front of a person and that person will examine the picture looking for anything familiar. Even if the examiner has no idea what he/she is looking at in a picture, he/she will still be able to make a statement about the picture, usually preceded by the words 'it looks like...' The image above is part of the surface of Mars, but is presented for its artistic value rather than its scientific value. When first viewed, this image solicited a statement that 'it looks like...' something seen in everyday life.

Perhaps a crystal; perhaps a plant of some sort?

Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

Repeated ruminal acidosis challenges in lactating dairy cows at high and low risk for developing acidosis: feed sorting.

PubMed

Devries, T J; Dohme, F; Beauchemin, K A

2008-10-01

An experiment was conducted to determine whether the susceptibility of cows to ruminal acidosis influences feed sorting and whether feed sorting changes during a bout of ruminal acidosis. Eight ruminally cannulated cows were assigned to 1 of 2 acidosis risk levels: low risk (LR, mid-lactation cows fed a 60% forage diet) or high risk (HR, early lactation cows fed a 45% forage diet). As a result, diets were intentionally confounded with milk production to represent 2 different acidosis risk scenarios. Cows were exposed to an acidosis challenge in each of two 14-d periods. Each period consisted of 3 baseline days, a feed restriction day (restricting TMR to 50% of ad libitum intake), an acidosis challenge day (1-h meal of 4 kg of ground barley/wheat before allocating the TMR), and a recovery phase. Ruminal pH was measured continuously for the first 9 d of each period using an indwelling system. Feed and orts were sampled for 2 baseline days, on the challenge day, and 1 and 3 d after the challenge day for each cow and subjected to particle size analysis. The separator contained 3 screens (18, 9, and 1.18 mm) and a bottom pan to determine the proportion of long, medium, short, and fine particles, respectively. Sorting was calculated as the actual intake of each particle size fraction expressed as a percentage of the predicted intake of that fraction. All cows sorted against the longest and finest TMR particles and sorted for medium-length particles. Sorting was performed to a greater extent by the HR cows, and this sorting was related to low ruminal pH. Both HR and LR cows altered their sorting behavior in response to acidosis challenges. For the HR cows, severe acidosis was associated with increased sorting for the longer particles in the diet and against the shorter particles, likely to lessen the effects of the very.

Flow cytometric sorting of fresh and frozen-thawed spermatozoa in the western lowland gorilla (Gorilla gorilla gorilla).

PubMed

O'Brien, J K; Stojanov, T; Crichton, E G; Evans, K M; Leigh, D; Maxwell, W M C; Evans, G; Loskutoff, N M

2005-08-01

We adapted flow cytometry technology for high-purity sorting of X chromosome-bearing spermatozoa in the western lowland gorilla (Gorilla gorilla gorilla). Our objectives were to develop methodologies for liquid storage of semen prior to sorting, sorting of liquid-stored and frozen-thawed spermatozoa, and assessment of sorting accuracy. In study 1, the in vitro sperm characteristics of gorilla ejaculates from one male were unchanged (P > 0.05) after 8 hr of liquid storage at 15 degrees C in a non-egg yolk diluent (HEPES-buffered modified Tyrode's medium). In study 2, we examined the efficacy of sorting fresh and frozen-thawed spermatozoa using human spermatozoa as a model for gorilla spermatozoa. Ejaculates from one male were split into fresh and frozen aliquots. X-enriched samples derived from both fresh and frozen-thawed human semen were of high purity, as determined by fluorescence in situ hybridization (FISH; 90.7%+/-2.3%, overall), and contained a high proportion of morphologically normal spermatozoa (86.0%+/-1.0%, overall). In study 3, we processed liquid-stored semen from two gorillas for sorting using a modification of methods for human spermatozoa. The sort rate for enrichment of X-bearing spermatozoa was 7.3+/-2.5 spermatozoa per second. The X-enriched samples were of high purity (single-sperm PCR: 83.7%) and normal morphology (79.0%+/-3.9%). In study 4 we examined frozen-thawed gorilla semen, and the sort rate (8.3+/-2.9 X-bearing sperm/sec), purity (89.7%), and normal morphology (81.4%+/-3.4%) were comparable to those of liquid-stored semen. Depending on the male and the type of sample used (fresh or frozen-thawed), 0.8-2.2% of gorilla spermatozoa in the processed ejaculate were present in the X-enriched sample. These results demonstrate that fresh or frozen-thawed gorilla spermatozoa can be flow cytometrically sorted into samples enriched for X-bearing spermatozoa. Copyright 2005 Wiley-Liss, Inc.

Paleomagnetism of the Red Dog Zn-Pb massive sulfide deposit in northern Alaska

USGS Publications Warehouse

Lewchuk, Michael T.; Leach, D.L.; Kelley, K.D.; Symons, David T. A.

2004-01-01

Paleomagnetic methods have isolated two ancient magnetizations in and around the Paleozoic shale-hosted Red Dog ore deposit in northern Alaska. A high-latitude, westerly magnetization carried by magnetite, termed characteristic remanent magnetization A, was found in rocks that have barite and/or substantial quartz replacement of barite. An intermediate- to low-latitude, southerly magnetization (characteristic remanent magnetization B) is carried by pyrrhotite and was found in rocks dominated by galena and sphalerite. The ages the two components are constrained by their relationship with geochemistry, radiometric age dating, and hypotheses for the Mesozoic tectonic history of the Brooks Range. Characteristic remanent magnetization A fails the fold test so it must postdate the end of Brookian orogenesis (??? 150 Ma). It is always found with replacement quartz that has a radiometric date (white mica from a vug, 39Ar/40Ar) of 126 Ma. The paleolatitude for characteristic remanent magnetization B is too shallow to be Mesozoic or younger, regardless of the model for the tectonic origin of northern Alaska, and must predate Brookian orogenesis. Geologic mapping suggests that most of the ore is syngenetic, formed at 330 to 340 Ma, and a radiometric date (Re-Os on pyrite) yields an age of 338 Ma. Since characteristic remanent magnetization B predates deformation, is found in mineralized rocks and is carried by pyrrhotite, it was probably acquired during the mineralizing process as well. The combined radiometric ages and paleomagnetic data sets can be best interpreted by assuming that northern Alaska was part of an accreted terrane that was translated northward by about 30?? into its current location relative to the rest of North America and then rotated counterclockwise by 50?? to 70??. This tectonic interpretation yields plausible magnetization ages for both characteristic remanent magnetization A and B. Geologic evidence, isotopic ages, and paleomagnetic data indicate formation of the deposit at a paleolatitude that is much lower than today. ?? 2004 by Economic Geology.

Preliminary Evaluation of GAOFEN-3 Polarimetric and Radiometric Accuracy by Corner Reflectors in Inner Mongolia

NASA Astrophysics Data System (ADS)

Shi, L.; Ding, X.; Li, P.; Yang, J.; Zhao, L.; Yang, L.; Chang, Y.; Yan, L.

2018-04-01

On August 10, 2016, China launched its first C-band full polarimetric radar satellite, named Gaofen-3 (GF-3), for urban and agriculture monitoring, landslide detection, ocean applications, etc. According to the design specification, GF-3 is expected to work at -35 dB crosstalk and 0.5 dB channel imbalance, with less than 10 degree error. The absolute radiometric bias is expected to be less than 1.5 dB in a single scene and 2.0 dB when operating for a long time. To complete the calibration and evaluation, the Institute of Electronics, Chinese Academy Sciences (IECAS) built a test site at Inner Mongolia, and deployed active reflectors (ARs) and trihedral corner reflectors (CRs) to solve and evaluate the hardware distortion. To the best of the authors' knowledge, the product accuracy of GF-3 has not been comprehensively evaluated in any open publication. The remote sensing community urgently requires a detailed report about the product accuracy and stability, before any subsequent application. From June to August of 2017, IECAS begun its second round ground campaign and deployed 10 CRs to evaluate product distortions. In this paper, we exploit Inner Mongolia CRs to investigate polarimetric and radiometric accuracy of QPSI I Stripmap. Although some CRs found fall into AR side lobe, the rest CRs enable us to preliminarily evaluate the accuracy of some special imaging beams. In the experimental part, the image of July 6, 2017 was checked by 5 trihedral CRs and the integration estimation method demonstrated the crosstalk varying from -42.65 to -32.74 dB, and the channel imbalance varying from -0.21 to 0.47 with phase error from -2.4 to 0.2 degree. Comparing with the theoretical radar cross-section of 1.235 m trihedral CR, i.e. 35 dB, the radiometric error varies about 0.20 ± 0.29 dB in HH channel and 0.40 ± 0.20 dB in VV channel.

OCRA radiometric cloud fractions for GOME-2 on MetOp-A/B

NASA Astrophysics Data System (ADS)

Lutz, R.; Loyola, D.; Gimeno García, S.; Romahn, F.

2015-12-01

This paper describes an approach for cloud parameter retrieval (radiometric cloud fraction estimation) using the polarization measurements of the Global Ozone Monitoring Experiment-2 (GOME-2) on-board the MetOp-A/B satellites. The core component of the Optical Cloud Recognition Algorithm (OCRA) is the calculation of monthly cloud-free reflectances for a global grid (resolution of 0.2° in longitude and 0.2° in latitude) and to derive radiometric cloud fractions. These cloud fractions will serve as a priori information for the retrieval of cloud top height (CTH), cloud top pressure (CTP), cloud top albedo (CTA) and cloud optical thickness (COT) with the Retrieval Of Cloud Information using Neural Networks (ROCINN) algorithm. This approach is already being implemented operationally for the GOME/ERS-2 and SCIAMACHY/ENVISAT sensors and here we present version 3.0 of the OCRA algorithm applied to the GOME-2 sensors. Based on more than six years of GOME-2A data (February 2007-June 2013), reflectances are calculated for ≈ 35 000 orbits. For each measurement a degradation correction as well as a viewing angle dependent and latitude dependent correction is applied. In addition, an empirical correction scheme is introduced in order to remove the effect of oceanic sun glint. A comparison of the GOME-2A/B OCRA cloud fractions with co-located AVHRR geometrical cloud fractions shows a general good agreement with a mean difference of -0.15±0.20. From operational point of view, an advantage of the OCRA algorithm is its extremely fast computational time and its straightforward transferability to similar sensors like OMI (Ozone Monitoring Instrument), TROPOMI (TROPOspheric Monitoring Instrument) on Sentinel 5 Precursor, as well as Sentinel 4 and Sentinel 5. In conclusion, it is shown that a robust, accurate and fast radiometric cloud fraction estimation for GOME-2 can be achieved with OCRA by using the polarization measurement devices (PMDs).

Exploring a Black Body Source as an Absolute Radiometric Calibration Standard and Comparison with a NIST Traced Lamp Standard

NASA Technical Reports Server (NTRS)

Green, Robert O.; Chrien, Thomas; Sarture, Chuck

2001-01-01

Radiometric calibration of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) is required for the scientific research and application objectives pursued with the spectroscopic measurements. Specifically calibration is required for: inter-comparison of AVIRIS data measured at different locations and at different times; analysis of AVIRIS data with data measured by other instruments; and analysis of AVIRIS data in conjunction with computer models. The primary effect of radiometric calibration is conversion of AVIRIS instrument response values (digitized numbers, or DN) to units of absolute radiance. For example, a figure shows the instrument response spectrum measured by AVIRIS over a portion of Rogers Dry Lake, California, and another figure shows the same spectrum calibrated to radiance. Only the calibrated spectrum may be quantitatively analyzed for science research and application objectives. Since the initial development of the AVIRIS instrument-radiometric calibration has been based upon a 1000-W irradiance lamp with a calibration traced to the National Institute of Standards and Technology (NIST). There are several advantages to this irradiance-lamp calibration approach. First, the considerable effort of NIST backs up the calibration. Second, by changing the distance to the lamp, the output can closely span the radiance levels measured by AVIRIS. Third, this type of standard is widely used. Fourth, these calibrated lamps are comparatively inexpensive. Conversely, there are several disadvantages to this approach as well. First, the lamp is not a primary standard. Second, the lamp output characteristics may change in an unknown manner through time. Third, it is difficult to assess, constrain, or improve the calibration uncertainty delivered with the lamp. In an attempt to explore the effect and potentially address some of these disadvantages a set of analyses and measurements comparing an irradiance lamp with a black-body source have been completed. This research is ongoing, and the current set of measurements, analyses, and results are presented in this paper.

OCRA radiometric cloud fractions for GOME-2 on MetOp-A/B

NASA Astrophysics Data System (ADS)

Lutz, Ronny; Loyola, Diego; Gimeno García, Sebastián; Romahn, Fabian

2016-05-01

This paper describes an approach for cloud parameter retrieval (radiometric cloud-fraction estimation) using the polarization measurements of the Global Ozone Monitoring Experiment-2 (GOME-2) onboard the MetOp-A/B satellites. The core component of the Optical Cloud Recognition Algorithm (OCRA) is the calculation of monthly cloud-free reflectances for a global grid (resolution of 0.2° in longitude and 0.2° in latitude) to derive radiometric cloud fractions. These cloud fractions will serve as a priori information for the retrieval of cloud-top height (CTH), cloud-top pressure (CTP), cloud-top albedo (CTA) and cloud optical thickness (COT) with the Retrieval Of Cloud Information using Neural Networks (ROCINN) algorithm. This approach is already being implemented operationally for the GOME/ERS-2 and SCIAMACHY/ENVISAT sensors and here we present version 3.0 of the OCRA algorithm applied to the GOME-2 sensors. Based on more than five years of GOME-2A data (April 2008 to June 2013), reflectances are calculated for ≈ 35 000 orbits. For each measurement a degradation correction as well as a viewing-angle-dependent and latitude-dependent correction is applied. In addition, an empirical correction scheme is introduced in order to remove the effect of oceanic sun glint. A comparison of the GOME-2A/B OCRA cloud fractions with colocated AVHRR (Advanced Very High Resolution Radiometer) geometrical cloud fractions shows a general good agreement with a mean difference of -0.15 ± 0.20. From an operational point of view, an advantage of the OCRA algorithm is its very fast computational time and its straightforward transferability to similar sensors like OMI (Ozone Monitoring Instrument), TROPOMI (TROPOspheric Monitoring Instrument) on Sentinel 5 Precursor, as well as Sentinel 4 and Sentinel 5. In conclusion, it is shown that a robust, accurate and fast radiometric cloud-fraction estimation for GOME-2 can be achieved with OCRA using polarization measurement devices (PMDs).

An on-chip imaging droplet-sorting system: a real-time shape recognition method to screen target cells in droplets with single cell resolution

NASA Astrophysics Data System (ADS)

Girault, Mathias; Kim, Hyonchol; Arakawa, Hisayuki; Matsuura, Kenji; Odaka, Masao; Hattori, Akihiro; Terazono, Hideyuki; Yasuda, Kenji

2017-01-01

A microfluidic on-chip imaging cell sorter has several advantages over conventional cell sorting methods, especially to identify cells with complex morphologies such as clusters. One of the remaining problems is how to efficiently discriminate targets at the species level without labelling. Hence, we developed a label-free microfluidic droplet-sorting system based on image recognition of cells in droplets. To test the applicability of this method, a mixture of two plankton species with different morphologies (Dunaliella tertiolecta and Phaeodactylum tricornutum) were successfully identified and discriminated at a rate of 10 Hz. We also examined the ability to detect the number of objects encapsulated in a droplet. Single cell droplets sorted into collection channels showed 91 ± 4.5% and 90 ± 3.8% accuracy for D. tertiolecta and P. tricornutum, respectively. Because we used image recognition to confirm single cell droplets, we achieved highly accurate single cell sorting. The results indicate that the integrated method of droplet imaging cell sorting can provide a complementary sorting approach capable of isolating single target cells from a mixture of cells with high accuracy without any staining.

An on-chip imaging droplet-sorting system: a real-time shape recognition method to screen target cells in droplets with single cell resolution.

PubMed

Girault, Mathias; Kim, Hyonchol; Arakawa, Hisayuki; Matsuura, Kenji; Odaka, Masao; Hattori, Akihiro; Terazono, Hideyuki; Yasuda, Kenji

2017-01-06

A microfluidic on-chip imaging cell sorter has several advantages over conventional cell sorting methods, especially to identify cells with complex morphologies such as clusters. One of the remaining problems is how to efficiently discriminate targets at the species level without labelling. Hence, we developed a label-free microfluidic droplet-sorting system based on image recognition of cells in droplets. To test the applicability of this method, a mixture of two plankton species with different morphologies (Dunaliella tertiolecta and Phaeodactylum tricornutum) were successfully identified and discriminated at a rate of 10 Hz. We also examined the ability to detect the number of objects encapsulated in a droplet. Single cell droplets sorted into collection channels showed 91 ± 4.5% and 90 ± 3.8% accuracy for D. tertiolecta and P. tricornutum, respectively. Because we used image recognition to confirm single cell droplets, we achieved highly accurate single cell sorting. The results indicate that the integrated method of droplet imaging cell sorting can provide a complementary sorting approach capable of isolating single target cells from a mixture of cells with high accuracy without any staining.

Automatic Spike Sorting Using Tuning Information

PubMed Central

Ventura, Valérie

2011-01-01

Current spike sorting methods focus on clustering neurons’ characteristic spike waveforms. The resulting spike-sorted data are typically used to estimate how covariates of interest modulate the firing rates of neurons. However, when these covariates do modulate the firing rates, they provide information about spikes’ identities, which thus far have been ignored for the purpose of spike sorting. This letter describes a novel approach to spike sorting, which incorporates both waveform information and tuning information obtained from the modulation of firing rates. Because it efficiently uses all the available information, this spike sorter yields lower spike misclassification rates than traditional automatic spike sorters. This theoretical result is verified empirically on several examples. The proposed method does not require additional assumptions; only its implementation is different. It essentially consists of performing spike sorting and tuning estimation simultaneously rather than sequentially, as is currently done. We used an expectation-maximization maximum likelihood algorithm to implement the new spike sorter. We present the general form of this algorithm and provide a detailed implementable version under the assumptions that neurons are independent and spike according to Poisson processes. Finally, we uncover a systematic flaw of spike sorting based on waveform information only. PMID:19548802

Automatic spike sorting using tuning information.

PubMed

Ventura, Valérie

2009-09-01

Current spike sorting methods focus on clustering neurons' characteristic spike waveforms. The resulting spike-sorted data are typically used to estimate how covariates of interest modulate the firing rates of neurons. However, when these covariates do modulate the firing rates, they provide information about spikes' identities, which thus far have been ignored for the purpose of spike sorting. This letter describes a novel approach to spike sorting, which incorporates both waveform information and tuning information obtained from the modulation of firing rates. Because it efficiently uses all the available information, this spike sorter yields lower spike misclassification rates than traditional automatic spike sorters. This theoretical result is verified empirically on several examples. The proposed method does not require additional assumptions; only its implementation is different. It essentially consists of performing spike sorting and tuning estimation simultaneously rather than sequentially, as is currently done. We used an expectation-maximization maximum likelihood algorithm to implement the new spike sorter. We present the general form of this algorithm and provide a detailed implementable version under the assumptions that neurons are independent and spike according to Poisson processes. Finally, we uncover a systematic flaw of spike sorting based on waveform information only.

Jab1 regulates Schwann cell proliferation and axonal sorting through p27

PubMed Central

Porrello, Emanuela; Rivellini, Cristina; Dina, Giorgia; Triolo, Daniela; Del Carro, Ubaldo; Ungaro, Daniela; Panattoni, Martina; Feltri, Maria Laura; Wrabetz, Lawrence; Pardi, Ruggero; Quattrini, Angelo

2014-01-01

Axonal sorting is a crucial event in nerve formation and requires proper Schwann cell proliferation, differentiation, and contact with axons. Any defect in axonal sorting results in dysmyelinating peripheral neuropathies. Evidence from mouse models shows that axonal sorting is regulated by laminin211– and, possibly, neuregulin 1 (Nrg1)–derived signals. However, how these signals are integrated in Schwann cells is largely unknown. We now report that the nuclear Jun activation domain–binding protein 1 (Jab1) may transduce laminin211 signals to regulate Schwann cell number and differentiation during axonal sorting. Mice with inactivation of Jab1 in Schwann cells develop a dysmyelinating neuropathy with axonal sorting defects. Loss of Jab1 increases p27 levels in Schwann cells, which causes defective cell cycle progression and aberrant differentiation. Genetic down-regulation of p27 levels in Jab1-null mice restores Schwann cell number, differentiation, and axonal sorting and rescues the dysmyelinating neuropathy. Thus, Jab1 constitutes a regulatory molecule that integrates laminin211 signals in Schwann cells to govern cell cycle, cell number, and differentiation. Finally, Jab1 may constitute a key molecule in the pathogenesis of dysmyelinating neuropathies. PMID:24344238

Feature extraction using extrema sampling of discrete derivatives for spike sorting in implantable upper-limb neural prostheses.

PubMed

Zamani, Majid; Demosthenous, Andreas

2014-07-01

Next generation neural interfaces for upper-limb (and other) prostheses aim to develop implantable interfaces for one or more nerves, each interface having many neural signal channels that work reliably in the stump without harming the nerves. To achieve real-time multi-channel processing it is important to integrate spike sorting on-chip to overcome limitations in transmission bandwidth. This requires computationally efficient algorithms for feature extraction and clustering suitable for low-power hardware implementation. This paper describes a new feature extraction method for real-time spike sorting based on extrema analysis (namely positive peaks and negative peaks) of spike shapes and their discrete derivatives at different frequency bands. Employing simulation across different datasets, the accuracy and computational complexity of the proposed method are assessed and compared with other methods. The average classification accuracy of the proposed method in conjunction with online sorting (O-Sort) is 91.6%, outperforming all the other methods tested with the O-Sort clustering algorithm. The proposed method offers a better tradeoff between classification error and computational complexity, making it a particularly strong choice for on-chip spike sorting.

A fully automated non-external marker 4D-CT sorting algorithm using a serial cine scanning protocol.

PubMed

Carnes, Greg; Gaede, Stewart; Yu, Edward; Van Dyk, Jake; Battista, Jerry; Lee, Ting-Yim

2009-04-07

Current 4D-CT methods require external marker data to retrospectively sort image data and generate CT volumes. In this work we develop an automated 4D-CT sorting algorithm that performs without the aid of data collected from an external respiratory surrogate. The sorting algorithm requires an overlapping cine scan protocol. The overlapping protocol provides a spatial link between couch positions. Beginning with a starting scan position, images from the adjacent scan position (which spatial match the starting scan position) are selected by maximizing the normalized cross correlation (NCC) of the images at the overlapping slice position. The process was continued by 'daisy chaining' all couch positions using the selected images until an entire 3D volume was produced. The algorithm produced 16 phase volumes to complete a 4D-CT dataset. Additional 4D-CT datasets were also produced using external marker amplitude and phase angle sorting methods. The image quality of the volumes produced by the different methods was quantified by calculating the mean difference of the sorted overlapping slices from adjacent couch positions. The NCC sorted images showed a significant decrease in the mean difference (p < 0.01) for the five patients.

Interval linear programming model for long-term planning of vehicle recycling in the Republic of Serbia under uncertainty.

PubMed

Simic, Vladimir; Dimitrijevic, Branka

2015-02-01

An interval linear programming approach is used to formulate and comprehensively test a model for optimal long-term planning of vehicle recycling in the Republic of Serbia. The proposed model is applied to a numerical case study: a 4-year planning horizon (2013-2016) is considered, three legislative cases and three scrap metal price trends are analysed, availability of final destinations for sorted waste flows is explored. Potential and applicability of the developed model are fully illustrated. Detailed insights on profitability and eco-efficiency of the projected contemporary equipped vehicle recycling factory are presented. The influences of the ordinance on the management of end-of-life vehicles in the Republic of Serbia on the vehicle hulks procuring, sorting generated material fractions, sorted waste allocation and sorted metals allocation decisions are thoroughly examined. The validity of the waste management strategy for the period 2010-2019 is tested. The formulated model can create optimal plans for procuring vehicle hulks, sorting generated material fractions, allocating sorted waste flows and allocating sorted metals. Obtained results are valuable for supporting the construction and/or modernisation process of a vehicle recycling system in the Republic of Serbia. © The Author(s) 2015.

An on-chip imaging droplet-sorting system: a real-time shape recognition method to screen target cells in droplets with single cell resolution

PubMed Central

Girault, Mathias; Kim, Hyonchol; Arakawa, Hisayuki; Matsuura, Kenji; Odaka, Masao; Hattori, Akihiro; Terazono, Hideyuki; Yasuda, Kenji

2017-01-01

A microfluidic on-chip imaging cell sorter has several advantages over conventional cell sorting methods, especially to identify cells with complex morphologies such as clusters. One of the remaining problems is how to efficiently discriminate targets at the species level without labelling. Hence, we developed a label-free microfluidic droplet-sorting system based on image recognition of cells in droplets. To test the applicability of this method, a mixture of two plankton species with different morphologies (Dunaliella tertiolecta and Phaeodactylum tricornutum) were successfully identified and discriminated at a rate of 10 Hz. We also examined the ability to detect the number of objects encapsulated in a droplet. Single cell droplets sorted into collection channels showed 91 ± 4.5% and 90 ± 3.8% accuracy for D. tertiolecta and P. tricornutum, respectively. Because we used image recognition to confirm single cell droplets, we achieved highly accurate single cell sorting. The results indicate that the integrated method of droplet imaging cell sorting can provide a complementary sorting approach capable of isolating single target cells from a mixture of cells with high accuracy without any staining. PMID:28059147

An improved infrared technique for sorting pecans

NASA Astrophysics Data System (ADS)

Graeve, Thorsten; Dereniak, Eustace L.; Lamonica, John A., Jr.

1991-10-01

This paper presents the results of a study of pecan spectral reflectances. It describes an experiment for measuring the contrast between several components of raw pecan product to be sorted. An analysis of the experimental data reveals high contrast ratios in the infrared spectrum, suggesting a potential improvement in sorting efficiency when separating pecan meat from shells. It is believed that this technique has the potential to dramatically improve the efficiency of current sorting machinery, and to reduce the cost of processing pecans for the consumer market.

[THE PRINCIPLES OF ORGANIZATION AND TREATMENT FOR SORTING OF WOUNDED PERSONS WITH A COMBAT SURGICAL TRAUMA OF EXTREMITIES ON THE IV LEVEL OF THE MEDICAL CARE PROVISION].

PubMed

Korohl, S O; Zherdev, I I; Domanskiy, A M

2015-12-01

Experience of medical sorting of 434 injured persons with a gun-shot woundings of extremities in 2014-2015 yrs is adduced. The principles of organization and treatment for medical sorting of wounded persons were elaborated. Prognostic intrahospital, diagnostic and evacuation--transport sorting was introduced in wounded persons in the IV level hospital, concerning severity of traumatic shock and prognosis of their survival.

Radiometric and spectral calibrations of the Geostationary Imaging Fourier Transform Spectrometer (GIFTS) using principle component analysis

NASA Astrophysics Data System (ADS)

Tian, Jialin; Smith, William L.; Gazarik, Michael J.

2008-10-01

The ultimate remote sensing benefits of the high resolution Infrared radiance spectrometers will be realized with their geostationary satellite implementation in the form of imaging spectrometers. This will enable dynamic features of the atmosphere's thermodynamic fields and pollutant and greenhouse gas constituents to be observed for revolutionary improvements in weather forecasts and more accurate air quality and climate predictions. As an important step toward realizing this application objective, the Geostationary Imaging Fourier Transform Spectrometer (GIFTS) Engineering Demonstration Unit (EDU) was successfully developed under the NASA New Millennium Program, 2000-2006. The GIFTS-EDU instrument employs three focal plane arrays (FPAs), which gather measurements across the long-wave IR (LWIR), short/mid-wave IR (SMWIR), and visible spectral bands. The raw GIFTS interferogram measurements are radiometrically and spectrally calibrated to produce radiance spectra, which are further processed to obtain atmospheric profiles via retrieval algorithms. The radiometric calibration is achieved using internal blackbody calibration references at ambient (260 K) and hot (286 K) temperatures. The absolute radiometric performance of the instrument is affected by several factors including the FPA off-axis effect, detector/readout electronics induced nonlinearity distortions, and fore-optics offsets. The GIFTS-EDU, being the very first imaging spectrometer to use ultra-high speed electronics to readout its large area format focal plane array detectors, operating at wavelengths as large as 15 microns, possessed non-linearity's not easily removable in the initial calibration process. In this paper, we introduce a refined calibration technique that utilizes Principle Component (PC) analysis to compensate for instrument distortions and artifacts remaining after the initial radiometric calibration process, thus, further enhance the absolute calibration accuracy. This method is applied to data collected during an atmospheric measurement experiment with the GIFTS, together with simultaneous observations by the accurately calibrated AERI (Atmospheric Emitted Radiance Interferometer), both simultaneously zenith viewing the sky through the same external scene mirror at ten-minute intervals throughout a cloudless day at Logan Utah on September 13, 2006. The PC vectors of the calibrated radiance spectra are defined from the AERI observations and regression matrices relating the initial GIFTS radiance PC scores to the AERI radiance PC scores are calculated using the least squares inverse method. A new set of accurately calibrated GIFTS radiances are produced using the first four PC scores in the regression model. Temperature and moisture profiles retrieved from the PC-calibrated GIFTS radiances are verified against radiosonde measurements collected throughout the GIFTS sky measurement period.

Sorted bed forms as self-organized patterns: 2. complex forcing scenarios

USGS Publications Warehouse

Coco, Giovanni; Murray, A. Brad; Green, Malcom O.; Thieler, E. Robert; Hume, T.M.

2007-01-01

We employ a numerical model to study the development of sorted bed forms under a variety of hydrodynamic and sedimentary conditions. Results indicate that increased variability in wave height decreases the growth rate of the features and can potentially give rise to complicated, a priori unpredictable, behavior. This happens because the system responds to a change in wave characteristics by attempting to self-organize into a patterned seabed of different geometry and spacing. The new wavelength might not have enough time to emerge before a new change in wave characteristics occurs, leading to less regular seabed configurations. The new seabed configuration is also highly dependent on the preexisting morphology, which further limits the possibility of predicting future behavior. For the same reasons, variability in the mean current magnitude and direction slows down the growth of features and causes patterns to develop that differ from classical sorted bed forms. Spatial variability in grain size distribution and different types of net sediment aggradation/degradation can also result in the development of sorted bed forms characterized by a less regular shape. Numerical simulations qualitatively agree with observed geometry (spacing and height) of sorted bed forms. Also in agreement with observations is that at shallower depths, sorted bed forms are more likely to be affected by changes in the forcing conditions, which might also explain why, in shallow waters, sorted bed forms are described as ephemeral features. Finally, simulations indicate that the different sorted bed form shapes and patterns observed in the field might not necessarily be related to diverse physical mechanisms. Instead, variations in sorted bed form characteristics may result from variations in local hydrodynamic and/or sedimentary conditions.

Handling of boar spermatozoa during and after flow cytometric sex-sorting process to improve their in vitro fertilizing ability.

PubMed

del Olmo, D; Parrilla, I; Gil, M A; Maside, C; Tarantini, T; Angel, M A; Roca, J; Martinez, E A; Vazquez, J M

2013-09-01

The objective of this study was to develop an adequate sperm handling protocol in order to obtain a sex-sorted sperm population with an optimal fertilizing ability. For this purpose, different aspects of the sorting procedure were examined. The effects of the high dilution rates (experiment 1), type of collection medium used (experiment 2), and sheath fluid composition (experiment 3) on sorted boar sperm quality and function were evaluated. Sperm quality was assessed by motility and viability tests, whereas sperm function was evaluated by an in vitro fertilization assay which determined the penetration and polyspermy rates as well as the mean number of sperm penetrating each oocyte. In experiment 1, the results obtained indicated that the high dilution rates did not cause a decrease either in the sperm quality parameters evaluated or the in vitro fertilization ability of spermatozoa. In experiment 2, although sperm quality was not affected, fertilizing ability was compromised after sorting, regardless of the collection medium that was used. In the experiment 3, all groups displayed adequate sperm quality values, but higher in vitro fertility parameters were obtained for spermatozoa sorted in presence of EDTA in the sheath fluid and egg yolk (EY) in the collection media when compared with those sorted in absence of these protective agents. No differences in penetration rates between unsorted highly diluted (control) and sorted sperm in the presence of EDTA and EY were observed. In conclusion, fertilizing ability was compromised in sex-sorted sperm. The addition of EDTA to sheath fluid and EY to collection medium improved boar sperm fertilizing ability, and both agents should be included as essential media components in future studies. Copyright © 2013 Elsevier Inc. All rights reserved.

Flow cytometric sex sorting affects CD4 membrane distribution and binding of exogenous DNA on bovine sperm cells.

PubMed

Domingues, William Borges; da Silveira, Tony Leandro Rezende; Komninou, Eliza Rossi; Monte, Leonardo Garcia; Remião, Mariana Härter; Dellagostin, Odir Antônio; Corcini, Carine Dahl; Varela Junior, Antônio Sergio; Seixas, Fabiana Kömmling; Collares, Tiago; Campos, Vinicius Farias

2017-08-01

Bovine sex-sorted sperm have been commercialized and successfully used for the production of transgenic embryos of the desired sex through the sperm-mediated gene transfer (SMGT) technique. However, sex-sorted sperm show a reduced ability to internalize exogenous DNA. The interaction between sperm cells and the exogenous DNA has been reported in other species to be a CD4-like molecule-dependent process. The flow cytometry-based sex-sorting process subjects the spermatozoa to different stresses causing changes in the cell membrane. The aim of this study was to elucidate the relationship between the redistribution of CD4-like molecules and binding of exogenous DNA to sex-sorted bovine sperm. In the first set of experiments, the membrane phospholipid disorder and the redistribution of the CD4 were evaluated. The second set of experiments was conducted to investigate the effect of CD4 redistribution on the mechanism of binding of exogenous DNA to sperm cells and the efficiency of lipofection in sex-sorted bovine sperm. Sex-sorting procedure increased the membrane phospholipid disorder and induced the redistribution of CD4-like molecules. Both X-sorted and Y-sorted sperm had decreased DNA bound to membrane in comparison with the unsorted sperm; however, the binding of the exogenous DNA was significantly increased with the addition of liposomes. Moreover, we demonstrated that the number of sperm-bound exogenous DNA was decreased when these cells were preincubated with anti-bovine CD4 monoclonal antibody, supporting our hypothesis that CD4-like molecules indeed play a crucial role in the process of exogenous DNA/bovine sperm cells interaction.

Physical Mechanisms Driving Cell Sorting in Hydra.

PubMed

Cochet-Escartin, Olivier; Locke, Tiffany T; Shi, Winnie H; Steele, Robert E; Collins, Eva-Maria S

2017-12-19

Cell sorting, whereby a heterogeneous cell mixture organizes into distinct tissues, is a fundamental patterning process in development. Hydra is a powerful model system for carrying out studies of cell sorting in three dimensions, because of its unique ability to regenerate after complete dissociation into individual cells. The physicists Alfred Gierer and Hans Meinhardt recognized Hydra's self-organizing properties more than 40 years ago. However, what drives cell sorting during regeneration of Hydra from cell aggregates is still debated. Differential motility and differential adhesion have been proposed as driving mechanisms, but the available experimental data are insufficient to distinguish between these two. Here, we answer this longstanding question by using transgenic Hydra expressing fluorescent proteins and a multiscale experimental and numerical approach. By quantifying the kinematics of single cell and whole aggregate behaviors, we show that no differences in cell motility exist among cell types and that sorting dynamics follow a power law with an exponent of ∼0.5. Additionally, we measure the physical properties of separated tissues and quantify their viscosities and surface tensions. Based on our experimental results and numerical simulations, we conclude that tissue interfacial tensions are sufficient to explain cell sorting in aggregates of Hydra cells. Furthermore, we demonstrate that the aggregate's geometry during sorting is key to understanding the sorting dynamics and explains the exponent of the power law behavior. Our results answer the long standing question of the physical mechanisms driving cell sorting in Hydra cell aggregates. In addition, they demonstrate how powerful this organism is for biophysical studies of self-organization and pattern formation. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Efficient Sampling of Parsimonious Inversion Histories with Application to Genome Rearrangement in Yersinia

PubMed Central

Darling, Aaron E.

2009-01-01

Inversions are among the most common mutations acting on the order and orientation of genes in a genome, and polynomial-time algorithms exist to obtain a minimal length series of inversions that transform one genome arrangement to another. However, the minimum length series of inversions (the optimal sorting path) is often not unique as many such optimal sorting paths exist. If we assume that all optimal sorting paths are equally likely, then statistical inference on genome arrangement history must account for all such sorting paths and not just a single estimate. No deterministic polynomial algorithm is known to count the number of optimal sorting paths nor sample from the uniform distribution of optimal sorting paths. Here, we propose a stochastic method that uniformly samples the set of all optimal sorting paths. Our method uses a novel formulation of parallel Markov chain Monte Carlo. In practice, our method can quickly estimate the total number of optimal sorting paths. We introduce a variant of our approach in which short inversions are modeled to be more likely, and we show how the method can be used to estimate the distribution of inversion lengths and breakpoint usage in pathogenic Yersinia pestis. The proposed method has been implemented in a program called “MC4Inversion.” We draw comparison of MC4Inversion to the sampler implemented in BADGER and a previously described importance sampling (IS) technique. We find that on high-divergence data sets, MC4Inversion finds more optimal sorting paths per second than BADGER and the IS technique and simultaneously avoids bias inherent in the IS technique. PMID:20333186

Recent progress in multi-electrode spike sorting methods

PubMed Central

Lefebvre, Baptiste; Yger, Pierre; Marre, Olivier

2017-01-01

In recent years, arrays of extracellular electrodes have been developed and manufactured to record simultaneously from hundreds of electrodes packed with a high density. These recordings should allow neuroscientists to reconstruct the individual activity of the neurons spiking in the vicinity of these electrodes, with the help of signal processing algorithms. Algorithms need to solve a source separation problem, also known as spike sorting. However, these new devices challenge the classical way to do spike sorting. Here we review different methods that have been developed to sort spikes from these large-scale recordings. We describe the common properties of these algorithms, as well as their main differences. Finally, we outline the issues that remain to be solved by future spike sorting algorithms. PMID:28263793

A review on automated sorting of source-separated municipal solid waste for recycling.

PubMed

Gundupalli, Sathish Paulraj; Hait, Subrata; Thakur, Atul

2017-02-01

A crucial prerequisite for recycling forming an integral part of municipal solid waste (MSW) management is sorting of useful materials from source-separated MSW. Researchers have been exploring automated sorting techniques to improve the overall efficiency of recycling process. This paper reviews recent advances in physical processes, sensors, and actuators used as well as control and autonomy related issues in the area of automated sorting and recycling of source-separated MSW. We believe that this paper will provide a comprehensive overview of the state of the art and will help future system designers in the area. In this paper, we also present research challenges in the field of automated waste sorting and recycling. Copyright © 2016 Elsevier Ltd. All rights reserved.

All sorts of options for food product sorting

USDA-ARS?s Scientific Manuscript database

Most food products undergo significant processing before arrival at the grocery store or local market. A major component of this processing includes sorting the product according to quality attributes such as size, color, sweetness, and ripeness. In addition, removal of defects or contaminants is a ...

Viable cell sorting of dinoflagellates by multi-parametric flow cytometry.

USDA-ARS?s Scientific Manuscript database

Electronic cell sorting for isolation and culture of dinoflagellates and other marine eukaryotic phytoplankton was compared to the traditional method of manually picking of cells using a micropipette. Trauma to electronically sorted cells was not a limiting factor as fragile dinoflagellates, such a...

Cloning of Plasmodium falciparum by single-cell sorting.

PubMed

Miao, Jun; Li, Xiaolian; Cui, Liwang

2010-10-01

Malaria parasite cloning is traditionally carried out mainly by using the limiting dilution method, which is laborious, imprecise, and unable to distinguish multiply-infected RBCs. In this study, we used a parasite engineered to express green fluorescent protein (GFP) to evaluate a single-cell sorting method for rapidly cloning Plasmodium falciparum. By dividing a two-dimensional scattergram from a cell sorter into 17 gates, we determined the parameters for isolating singly-infected erythrocytes and sorted them into individual cultures. Pre-gating of the engineered parasites for GFP allowed the isolation of almost 100% GFP-positive clones. Compared with the limiting dilution method, the number of parasite clones obtained by single-cell sorting was much higher. Molecular analyses showed that parasite isolates obtained by single-cell sorting were highly homogenous. This highly efficient single-cell sorting method should prove very useful for cloning both P. falciparum laboratory populations from genetic manipulation experiments and clinical samples. Copyright 2010 Elsevier Inc. All rights reserved.

Sperm sexing in sheep and cattle: the exception and the rule.

PubMed

de Graaf, S P; Beilby, K H; Underwood, S L; Evans, G; Maxwell, W M C

2009-01-01

Flow cytometric sorting for the preselection of sex has progressed considerably in the 20 years since its inception. This technique has allowed the production of pre-sexed offspring in a multitude of species and become a commercial success in cattle around the world. However, due to the stress inherent to the sex-sorting process, sex-sorted spermatozoa are widely recognized as functionally compromised in terms of their fertilizing lifespan within the female reproductive tract as a result of reduced motility and viability and changed functional state. These characteristics, when compared to non-sorted controls, are manifest in vivo as lower fertility. However, improvements to the technology and a greater understanding of its biological impact have facilitated recent developments in sheep, showing sex-sorting is capable of selecting a functionally superior population in terms of both in vitro and in vivo function. These results are reviewed in the context of recent developments in other species and the reasons for success after artificial insemination with sex-sorted ram spermatozoa are discussed.

Queue and stack sorting algorithm optimization and performance analysis

NASA Astrophysics Data System (ADS)

Qian, Mingzhu; Wang, Xiaobao

2018-04-01

Sorting algorithm is one of the basic operation of a variety of software development, in data structures course specializes in all kinds of sort algorithm. The performance of the sorting algorithm is directly related to the efficiency of the software. A lot of excellent scientific research queue is constantly optimizing algorithm, algorithm efficiency better as far as possible, the author here further research queue combined with stacks of sorting algorithms, the algorithm is mainly used for alternating operation queue and stack storage properties, Thus avoiding the need for a large number of exchange or mobile operations in the traditional sort. Before the existing basis to continue research, improvement and optimization, the focus on the optimization of the time complexity of the proposed optimization and improvement, The experimental results show that the improved effectively, at the same time and the time complexity and space complexity of the algorithm, the stability study corresponding research. The improvement and optimization algorithm, improves the practicability.

Agricultural produce grading and sorting system using color CCD and new color identification algorithm

NASA Astrophysics Data System (ADS)

Wang, Dongsheng; Zou, Jizuo; Yang, Yunping; Dong, Jianhua; Zhang, Yuanxiang

1996-10-01

A high-speed automatic agricultural produce grading and sorting system using color CCD and new color identification algorithm has been developed. In a typical application, the system can sort almonds into tow output grades according to their color. Almonds ar rich in 18 kinds of amino acids and 13 kinds of micro minerals and vitamins and can be made into almond drink. In order to ensure the drink quality, almonds must be sorted carefully before being made into a drink. Using this system, almonds can be sorted into two grades: up to grade and below grade almonds or foreign materials. A color CCD inspects the almonds passing on a conveyor of rotating rollers, a color identification algorithm grades almonds and distinguishes foreign materials from almonds. Employing an elaborately designed mechanism, the below grade almonds and foreign materials can be removed effectively from the raw almonds. This system can be easily adapted for inspecting and sorting other kinds of agricultural produce such as peanuts, beans tomatoes and so on.

The tetraspanin CD63 regulates ESCRT-independent and dependent endosomal sorting during melanogenesis

PubMed Central

van Niel, Guillaume; Charrin, Stéphanie; Simoes, Sabrina; Romao, Maryse; Rochin, Leila; Saftig, Paul; Marks, Michael S.; Rubinstein, Eric; Raposo, Graça

2011-01-01

Summary Cargo sorting to intraluminal vesicles (ILVs) of multivesicular endosomes is required for numerous physiological processes including lysosome-related organelle (LRO) biogenesis. PMEL – a component of melanocyte LROs (melanosomes) – is sorted to ILVs in an ESCRT-independent manner, where it is proteolytically processed and assembled into functional amyloid fibrils during melanosome maturation. Here we show that the tetraspanin CD63 directly participates in ESCRT-independent sorting of the PMEL luminal domain, but not of traditional ESCRT-dependent cargoes, to ILVs. Inactivating CD63 in cell culture or in mice impairs amyloidogenesis and downstream melanosome morphogenesis. Whereas CD63 is required for normal PMEL luminal domain sorting, the disposal of the remaining PMEL transmembrane fragment requires functional ESCRTs but not CD63. In the absence of CD63, the PMEL luminal domain follows this fragment and is targeted for ESCRT-dependent degradation. Our data thus reveal a tight interplay regulated by CD63 between two distinct endosomal ILV sorting processes for a single cargo during LRO biogenesis. PMID:21962903

The sorting of a small potassium channel in mammalian cells can be shifted between mitochondria and plasma membrane.

PubMed

von Charpuis, Charlotte; Meckel, Tobias; Moroni, Anna; Thiel, Gerhard

2015-07-01

The two small and similar viral K(+) channels Kcv and Kesv are sorted in mammalian cells and yeast to different destinations. Analysis of the sorting pathways shows that Kcv is trafficking via the secretory pathway to the plasma membrane, while Kesv is inserted via the TIM/TOM complex to the inner membrane of mitochondria. Studies with Kesv mutants show that an N-terminal mitochondrial targeting sequence in this channel is neither necessary nor sufficient for sorting of Kesv the mitochondria. Instead the sorting of Kesv can be redirected from the mitochondria to the plasma membrane by an insertion of ≥2 amino acids in a position sensitive manner into the C-terminal transmembrane domain (TMD2) of this channel. The available data advocate the presence of a C-terminal sorting signal in TMD2 of Kesv channel, which is presumably not determined by the length of this domain. Copyright © 2014. Published by Elsevier Ltd.

A novel method for isolating podocytes using magnetic activated cell sorting.

PubMed

Murakami, Ayumi; Oshiro, Hisashi; Kanzaki, Seiichi; Yamaguchi, Akira; Yamanaka, Shoji; Furuya, Mitsuko; Miura, Satoshi; Kanno, Hiroshi; Nagashima, Yoji; Aoki, Ichiro; Nagahama, Kiyotaka

2010-12-01

A large body of accumulated data has now revealed that podocytes play a major role in the development of proteinuria. However, the mechanisms of podocyte injury, leading to foot process effacement and proteinuria, are still unclear partly due to the current lack of an appropriate strategy for preparing podocytes. In this study, we have developed a novel method of rapid isolation of podocytes from mice using magnetic activated cell sorting with an anti-nephrin antibody. After endothelial cell depletion using anti-CD31 antibody, nephrin-positive cells were prepared from mouse kidneys using magnetic activated cell sorting with polyclonal rabbit anti-nephrin antibody. Purity of the positively sorted cells was determined by confocal microscopy and fluorescence-activated cell sorting (FACS) analysis. Expression profiles of podocyte-specific molecules in the sorted fractions were characterized by qualitative PCR and immunoblot analysis. Nephrin-positive cells, isolated from mouse kidneys within 6 h, showed dual positivity for synaptopodin and rabbit IgG on confocal microscopy. FACS analysis revealed that the purity of the positively sorted fractions was ∼75%. The nephrin-positive cells sorted by this approach showed a significantly higher expression of podocyte-specific molecules compared with nephrin-negative fractions. These data strongly suggest that our novel method for isolating podocytes has great utility for various downstream applications such as genomic analysis, proteomics and transcriptomics to elucidate molecular profiling of podocyte biology in vivo compared with conventional methods as our approach requires only several hours to complete and no tissue culture.

Label-free density difference amplification-based cell sorting.

PubMed

Song, Jihwan; Song, Minsun; Kang, Taewook; Kim, Dongchoul; Lee, Luke P

2014-11-01

The selective cell separation is a critical step in fundamental life sciences, translational medicine, biotechnology, and energy harvesting. Conventional cell separation methods are fluorescent activated cell sorting and magnetic-activated cell sorting based on fluorescent probes and magnetic particles on cell surfaces. Label-free cell separation methods such as Raman-activated cell sorting, electro-physiologically activated cell sorting, dielectric-activated cell sorting, or inertial microfluidic cell sorting are, however, limited when separating cells of the same kind or cells with similar sizes and dielectric properties, as well as similar electrophysiological phenotypes. Here we report a label-free density difference amplification-based cell sorting (dDACS) without using any external optical, magnetic, electrical forces, or fluidic activations. The conceptual microfluidic design consists of an inlet, hydraulic jump cavity, and multiple outlets. Incoming particles experience gravity, buoyancy, and drag forces in the separation chamber. The height and distance that each particle can reach in the chamber are different and depend on its density, thus allowing for the separation of particles into multiple outlets. The separation behavior of the particles, based on the ratio of the channel heights of the inlet and chamber and Reynolds number has been systematically studied. Numerical simulation reveals that the difference between the heights of only lighter particles with densities close to that of water increases with increasing the ratio of the channel heights, while decreasing Reynolds number can amplify the difference in the heights between the particles considered irrespective of their densities.

Spontaneous cell sorting of fibroblasts and keratinocytes creates an organotypic human skin equivalent.

PubMed

Wang, C K; Nelson, C F; Brinkman, A M; Miller, A C; Hoeffler, W K

2000-04-01

We show that an inherent ability of two distinct cell types, keratinocytes and fibroblasts, can be relied upon to accurately reconstitute full-thickness human skin including the dermal-epidermal junction by a cell-sorting mechanism. A cell slurry containing both cell types added to silicone chambers implanted on the backs of severe combined immunodeficient mice sorts out to reconstitute a clearly defined dermis and stratified epidermis within 2 wk, forming a cell-sorted skin equivalent. Immunostaining of the cell-sorted skin equivalent with human cell markers showed patterns similar to those of normal full-thickness skin. We compared the cell-sorted skin equivalent model with a composite skin model also made on severe combined immunodeficient mice. The composite grafts were constructed from partially differentiated keratinocyte sheets placed on top of a dermal equivalent constructed of devitalized dermis. Electron microscopy revealed that both models formed ample numbers of normal appearing hemidesmosomes. The cell-sorted skin equivalent model, however, had greater numbers of keratin intermediate filaments within the basal keratinocytes that connected to hemidesmosomes, and on the dermal side both collagen filaments and anchoring fibril connections to the lamina densa were more numerous compared with the composite model. Our results may provide some insight into why, in clinical applications for treating burns and other wounds, composite grafts may exhibit surface instability and blistering for up to a year following grafting, and suggest the possible usefulness of the cell-sorted skin equivalent in future grafting applications.

Working spectacles for sorting mail.

PubMed

Hemphälä, Hillevi; Dahlqvist, Camilla; Nordander, Catarina; Gao, Chuansi; Kuklane, Kalev; Nylén, Per; Hansson, Gert-Åke

2014-01-01

Sorting mail into racks for postmen is visually demanding work. This can result in backward inclination of their heads, especially more pronounced for those who use progressive addition lenses. To evaluate the effects of customized working spectacles on the physical workload of postmen. Twelve male postmen sorted mail on two occasions: once using their private progressive spectacles and once using customized sorting spectacles with inverted progressive lenses. Postures and movements of the head, upper back, neck, and upper arms were measured by inclinometry. The muscular load of the trapezius was measured by surface electromyography. With the customized sorting spectacles, both the backward inclination of the head and backward flexion of the neck were reduced (3°), as well as the muscular load of the right upper trapezius, compared to sorting with private spectacles. However, with the sorting spectacles, there was a tendency for increased neck forward flexion, and increased sorting time. The reduction in work load may reduce the risk for developing work-related musculoskeletal disorders due to the positive reduction of the backward inclination of the head. But the tendency for increased neck forward flexion may reduce the positive effects. However, the magnitude of the possible reduction is difficult to predict, especially since quantitative data on exposure-response relationships are unknown. Alternative working spectacles with inverted near progressive lenses ought to be evaluated. They should still result in a positive reduced backward inclination of the head and may not cause any increased forward flexion.

Mauna Kea Observatory infrared observations

NASA Technical Reports Server (NTRS)

Jefferies, J. T.

1974-01-01

Galactic and solar system infrared observations are reported using a broad variety of radiometric and spectroscopic instrumentation. Infrared programs and papers published during this period are listed.

Trend analysis of Terra/ASTER/VNIR radiometric calibration coefficient through onboard and vicarious calibrations as well as cross calibration with MODIS

NASA Astrophysics Data System (ADS)

Arai, Kohei

2012-07-01

More than 11 years Radiometric Calibration Coefficients (RCC) derived from onboard and vicarious calibrations are compared together with cross comparison to the well calibrated MODIS RCC. Fault Tree Analysis (FTA) is also conducted for clarification of possible causes of the RCC degradation together with sensitivity analysis for vicarious calibration. One of the suspects of causes of RCC degradation is clarified through FTA. Test site dependency on vicarious calibration is quite obvious. It is because of the vicarious calibration RCC is sensitive to surface reflectance measurement accuracy, not atmospheric optical depth. The results from cross calibration with MODIS support that significant sensitivity of surface reflectance measurements on vicarious calibration.

Electronic transport characterization of silicon wafers by spatially resolved steady-state photocarrier radiometric imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Qian; University of the Chinese Academy of Sciences, Beijing 100039; Li, Bincheng, E-mail: bcli@ioe.ac.cn

2015-09-28

Spatially resolved steady-state photocarrier radiometric (PCR) imaging technique is developed to characterize the electronic transport properties of silicon wafers. Based on a nonlinear PCR theory, simulations are performed to investigate the effects of electronic transport parameters (the carrier lifetime, the carrier diffusion coefficient, and the front surface recombination velocity) on the steady-state PCR intensity profiles. The electronic transport parameters of an n-type silicon wafer are simultaneously determined by fitting the measured steady-state PCR intensity profiles to the three-dimensional nonlinear PCR model. The determined transport parameters are in good agreement with the results obtained by the conventional modulated PCR technique withmore » multiple pump beam radii.« less

The Moon Mineralogy (M3) Imaging Spectrometer: Early Assessment of the Spectral, Radiometric, Spatial and Uniformity Properties

NASA Technical Reports Server (NTRS)

Green, Robert O.; Pieters, C. M.; Boardman, J.; Barr, D.; Bruce, C.; Bousman, J.; Chatterjee, A.; Eastwood, M.; Essandoh, V.; Geier, S.;

Antiquity of man in America indicated by radiometric dates on the Yuha burial site

USGS Publications Warehouse

Bischoff, J.L.; Merriam, R.; Childers, W.M.; Protsch, R.

1976-01-01

MUCH evidence suggests that man was present in the Western Hemisphere before 12,000 yr ago, but the case has remained less than conclusive 1. In some situations, the geological age of the site is reasonably well established but the association or nature of the artefacts is questionable2,3. In other cases, museum specimens of human bones dated by radiocarbon analysis of collagen lack desirable information concerning site location, geology, and stratigraphy even though the accuracy of their absolute ages seems valid4-6. We report here the results of radiometric dates of the Yuha burial site from Imperial County, California, for which the geology and stratigraphy have been documented and reported in detail7. ?? 1976 Nature Publishing Group.

Preliminary results of radiometric measurements of clear air and cloud brightness (antenna) temperatures at 37GHz

NASA Astrophysics Data System (ADS)

Arakelyan, A. K.; Hambaryan, A. K.; Arakelyan, A. A.

2012-05-01

In this paper the results of polarization measurements of clear air and clouds brightness temperatures at 37GHz are presented. The results were obtained during the measurements carried out in Armenia from the measuring complex built under the framework of ISTC Projects A-872 and A-1524. The measurements were carried out at vertical and horizontal polarizations, under various angles of sensing by Ka-band combined scatterometric-radiometric system (ArtAr-37) developed and built by ECOSERV Remote Observation Centre Co.Ltd. under the framework of the above Projects. In the paper structural and operational features of the utilized system and the whole measuring complex will be considered and discussed as well.

Validation of the Thematic Mapper radiometric and geometric correction algorithms

NASA Technical Reports Server (NTRS)

Fischel, D.

1984-01-01

The radiometric and geometric correction algorithms for Thematic Mapper are critical to subsequent successful information extraction. Earlier Landsat scanners, known as Multispectral Scanners, produce imagery which exhibits striping due to mismatching of detector gains and biases. Thematic Mapper exhibits the same phenomenon at three levels: detector-to-detector, scan-to-scan, and multiscan striping. The cause of these variations has been traced to variations in the dark current of the detectors. An alternative formulation has been tested and shown to be very satisfactory. Unfortunately, the Thematic Mapper detectors exhibit saturation effects suffered while viewing extensive cloud areas, and is not easily correctable. The geometric correction algorithm has been shown to be remarkably reliable. Only minor and modest improvements are indicated and shown to be effective.

Radiometry of water turbidity measurements

NASA Technical Reports Server (NTRS)

Mccluney, W. R.

1974-01-01

An examination of a number of measurements of turbidity reported in the literature reveals considerable variability in the definitions, units, and measurement techniques used. Many of these measurements differ radically in the optical quantity measured. The radiometric basis of each of the most common definitions of turbidity is examined. Several commercially available turbidimeters are described and their principles of operation are evaluated radiometrically. It is recommended that the term turbidity be restricted to measurements based upon the light scattered by the sample with that scattered by standard suspensions of known turbidity. It is also recommended that the measurement procedure be standardized by requiring the use of Formazin as the turbidity standardizing material and that the Formazin Turbidity Unit (FTU) be adopted as the standard unit of turbidity.

Infrared temperature measurements over bare soil and vegetation - A HAPEX perspective

NASA Technical Reports Server (NTRS)

Carlson, Toby N.; Perry, Eileen M.; Taconet, Odile

1987-01-01

Preliminary analyses of aircraft and ground measurements made in France during the HAPEX experiment show that horizontal radiometric surface temperature variations, as viewed by aircraft, can reflect the vertical profile of soil moisture (soil versus root zone) because of horizontal variations in vegetation density. Analyses based on one day's data show that, although horizontal variations in soil moisture were small, the vertical differences between a dry surface and a wet root zone were large. Horizontal temperature differences between bare soil, corn and oats reflect differences in the fractional vegetation cover, as seen by the radiometer. On the other hand, these horizontal variations in radiometric surface temperature seem to reflect real horizontal variations in surface turbulent energy fluxes.

Characterizing the scientific potential of satellite sensors. [San Francisco, California

NASA Technical Reports Server (NTRS)

1984-01-01

Eleven thematic mapper (TM) radiometric calibration programs were tested and evaluated in support of the task to characterize the potential of LANDSAT TM digital imagery for scientific investigations in the Earth sciences and terrestrial physics. Three software errors related to integer overflow, divide by zero, and nonexist file group were found and solved. Raw, calibrated, and corrected image groups that were created and stored on the Barker2 disk are enumerated. Black and white pixel print files were created for various subscenes of a San Francisco scene (ID 40392-18152). The development of linear regression software is discussed. The output of the software and its function are described. Future work in TM radiometric calibration, image processing, and software development is outlined.

System implications of large radiometric array antennas

NASA Technical Reports Server (NTRS)

Levis, C. A.; Lin, H. C.

1976-01-01

Current radiometric earth and atmospheric sensing systems in the centimeter wavelength range generally employ a directive antenna connected through a single terminal pair to a Dicke receiver. It is shown that this approach does not lend itself to systems with greatly increased spatial resolution. Signal to noise considerations relating to antenna efficiency force the introduction of active elements at the subarray level; thus, if Dicke switching is to be used, it must be distributed throughout the system. Some possible approaches are suggested. The introduction of active elements at the subarray level is found to ease the design constraints on time delay elements, necessary for bandwidth, and on multiple beam generation, required in order to achieve sufficient integration time with high resolution.

Phase difference statistics related to sensor and forest parameters

NASA Technical Reports Server (NTRS)

Lopes, A.; Mougin, E.; Beaudoin, A.; Goze, S.; Nezry, E.; Touzi, R.; Karam, M. A.; Fung, A. K.

1992-01-01

The information content of ordinary synthetic aperture radar (SAR) data is principally contained in the radiometric polarization channels, i.e., the four Ihh, Ivv, Ihv and Ivh backscattered intensities. In the case of clutter, polarimetric information is given by the four complex degrees of coherence, from which the mean polarization phase differences (PPD), correlation coefficients or degrees of polarization can be deduced. For radiometric features, the polarimetric parameters are corrupted by multiplicative speckle noise and by some sensor effects. The PPD distribution is related to the sensor, speckle and terrain properties. Experimental results are given for the variation of the terrain hh/vv mean phase difference and magnitude of the degree of coherence observed on bare soil and on different pine forest stands.

Scanner imaging systems, aircraft

NASA Technical Reports Server (NTRS)

Ungar, S. G.

1982-01-01

The causes and effects of distortion in aircraft scanner data are reviewed and an approach to reduce distortions by modelling the effect of aircraft motion on the scanner scene is discussed. With the advent of advanced satellite borne scanner systems, the geometric and radiometric correction of aircraft scanner data has become increasingly important. Corrections are needed to reliably simulate observations obtained by such systems for purposes of evaluation. It is found that if sufficient navigational information is available, aircraft scanner coordinates may be related very precisely to planimetric ground coordinates. However, the potential for a multivalue remapping transformation (i.e., scan lines crossing each other), adds an inherent uncertainty, to any radiometric resampling scheme, which is dependent on the precise geometry of the scan and ground pattern.

The PreferenSort: A Holistic Instrument for Career Counseling

ERIC Educational Resources Information Center

Amit, Adi; Sagiv, Lilach

2013-01-01

We present the PreferenSort, a career counseling instrument that derives counselees' vocational interests from their preferences among occupational titles. The PreferenSort allows for a holistic decision process, while taking into account the full complexity of occupations and encouraging deliberation about one's preferences and acceptable…

Processes of Overall Similarity Sorting in Free Classification

ERIC Educational Resources Information Center

Milton, Fraser; Longmore, Christopher A.; Wills, A. J.

2008-01-01

The processes of overall similarity sorting were investigated in 5 free classification experiments. Experiments 1 and 2 demonstrated that increasing time pressure can reduce the likelihood of overall similarity categorization. Experiment 3 showed that a concurrent load also reduced overall similarity sorting. These findings suggest that overall…

Log sort yard economics, planning, and feasibility

Treesearch

John Rusty Dramm; Robert Govett; Ted Bilek; Gerry L. Jackson

2004-01-01

This publication discusses basic marketing and economic concepts, planning approach, and feasibility methodology for assessing log sort yard operations. Special attention is given to sorting small diameter and underutilized logs from forest restoration, fuels reduction, and thinning operations. A planned programming approach of objectively determining the feasibility...

A multispectral sorting device for isolating single wheat kernels with high protein content

USDA-ARS?s Scientific Manuscript database

Automated sorting of single wheat kernels according to protein content was demonstrated using two novel multispectral sorting devices with different spectral ranges; 470-1070 nm (silicone based detector) and 910nm-1550 nm (InGaAs based detector). The multispectral data were acquired by rapidly (~12...

Bio optofluidics cell sorter: cell-BOCS concept and applications

NASA Astrophysics Data System (ADS)

Roth, Tue; Glückstad, Jesper

2012-03-01

The cell-BOCS is a novel microfluidics based cell-sorting instrument utilizing next generation optical trapping technology developed at the Technical University of Denmark. It is targeted emerging bio-medical research and diagnostics markets where it for certain applications offers a number of advantages over conventional fluorescence activated cell-sorting (FACSTM) technology. Advantages include gentle handling of cells, sterile sorting, easy operation, small footprint and lower cost allowing out-of-core-facility use. Application examples are found within sorting of fragile transfected cells, high value samples and primary cell lines, where traditional FACS technology has limited application due to it's droplet-based approach to cell-sorting. In the diagnostics field, in particular applying the cell-BOCS for isolating pure populations of circulating tumor cells is an area that has generated a lot of interest.

Recent progress in multi-electrode spike sorting methods.

PubMed

Lefebvre, Baptiste; Yger, Pierre; Marre, Olivier

2016-11-01

In recent years, arrays of extracellular electrodes have been developed and manufactured to record simultaneously from hundreds of electrodes packed with a high density. These recordings should allow neuroscientists to reconstruct the individual activity of the neurons spiking in the vicinity of these electrodes, with the help of signal processing algorithms. Algorithms need to solve a source separation problem, also known as spike sorting. However, these new devices challenge the classical way to do spike sorting. Here we review different methods that have been developed to sort spikes from these large-scale recordings. We describe the common properties of these algorithms, as well as their main differences. Finally, we outline the issues that remain to be solved by future spike sorting algorithms. Copyright © 2017 Elsevier Ltd. All rights reserved.

Acoustic bubble sorting for ultrasound contrast agent enrichment.

PubMed

Segers, Tim; Versluis, Michel

2014-05-21

An ultrasound contrast agent (UCA) suspension contains encapsulated microbubbles with a wide size distribution, with radii ranging from 1 to 10 μm. Medical transducers typically operate at a single frequency, therefore only a small selection of bubbles will resonate to the driving ultrasound pulse. Thus, the sensitivity can be improved by narrowing down the size distribution. Here, we present a simple lab-on-a-chip method to sort the population of microbubbles on-chip using a traveling ultrasound wave. First, we explore the physical parameter space of acoustic bubble sorting using well-defined bubble sizes formed in a flow-focusing device, then we demonstrate successful acoustic sorting of a commercial UCA. This novel sorting strategy may lead to an overall improvement of the sensitivity of contrast ultrasound by more than 10 dB.

The Role of the Clathrin Adaptor AP-1: Polarized Sorting and Beyond

PubMed Central

Nakatsu, Fubito; Hase, Koji; Ohno, Hiroshi

2014-01-01

The selective transport of proteins or lipids by vesicular transport is a fundamental process supporting cellular physiology. The budding process involves cargo sorting and vesicle formation at the donor membrane and constitutes an important process in vesicular transport. This process is particularly important for the polarized sorting in epithelial cells, in which the cargo molecules need to be selectively sorted and transported to two distinct destinations, the apical or basolateral plasma membrane. Adaptor protein (AP)-1, a member of the AP complex family, which includes the ubiquitously expressed AP-1A and the epithelium-specific AP-1B, regulates polarized sorting at the trans-Golgi network and/or at the recycling endosomes. A growing body of evidence, especially from studies using model organisms and animals, demonstrates that the AP-1-mediated polarized sorting supports the development and physiology of multi-cellular units as functional organs and tissues (e.g., cell fate determination, inflammation and gut immune homeostasis). Furthermore, a possible involvement of AP-1B in the pathogenesis of human diseases, such as Crohn’s disease and cancer, is now becoming evident. These data highlight the significant contribution of AP-1 complexes to the physiology of multicellular organisms, as master regulators of polarized sorting in epithelial cells. PMID:25387275

Application of Quality Function Deployment (QFD) method and kano model to redesign fresh fruit bunches sorting tool

NASA Astrophysics Data System (ADS)

Anizar; Siregar, I.; Yahya, I.; Yesika, N.

2018-02-01

The activity of lowering fresh fruit bunches (FFB) from truck to sorting floor is performed manually by workers using a sorting tool. Previously, the sorting tool used is a pointed iron bar with a T-shaped handle. Changes made to the sorting tool causes several complaints on worker and affect the time to lower the fruit. The purpose of this article is to obtain the design of an FFB sorting tool that suits the needs of these workers by applying the Quality Function Deployment (QFD) and Kano Model methods. Both of the two methods will be integrated to find the design that matches workers’ image and psychological feeling. The main parameters are to obtain the customer requirements of the palm fruit loading workers, to find the most important technical characteristics and critical part affecting the quality of the FFB sorting tool. The customer requirements of the palm loading workers are the following : the color of the coating paint is gray, the bar material is made of stainless pipe, the main grip coating material is made of grip, the tip material is made of the spring steel, the additional grip is made of rubber and the handle is of triangular shape.

Co-assembly of Viral Envelope Glycoproteins Regulates Their Polarized Sorting in Neurons

PubMed Central

Mardones, Gonzalo A.; Bonifacino, Juan S.

2014-01-01

Newly synthesized envelope glycoproteins of neuroinvasive viruses can be sorted in a polarized manner to the somatodendritic and/or axonal domains of neurons. Although critical for transneuronal spread of viruses, the molecular determinants and interregulation of this process are largely unknown. We studied the polarized sorting of the attachment (NiV-G) and fusion (NiV-F) glycoproteins of Nipah virus (NiV), a paramyxovirus that causes fatal human encephalitis, in rat hippocampal neurons. When expressed individually, NiV-G exhibited a non-polarized distribution, whereas NiV-F was specifically sorted to the somatodendritic domain. Polarized sorting of NiV-F was dependent on interaction of tyrosine-based signals in its cytosolic tail with the clathrin adaptor complex AP-1. Co-expression of NiV-G with NiV-F abolished somatodendritic sorting of NiV-F due to incorporation of NiV-G•NiV-F complexes into axonal transport carriers. We propose that faster biosynthetic transport of unassembled NiV-F allows for its proteolytic activation in the somatodendritic domain prior to association with NiV-G and axonal delivery of NiV-G•NiV-F complexes. Our study reveals how interactions of viral glycoproteins with the host's transport machinery and between themselves regulate their polarized sorting in neurons. PMID:24831812

The solution space of sorting by DCJ.

PubMed

Braga, Marília D V; Stoye, Jens

2010-09-01

In genome rearrangements, the double cut and join (DCJ) operation, introduced by Yancopoulos et al. in 2005, allows one to represent most rearrangement events that could happen in multichromosomal genomes, such as inversions, translocations, fusions, and fissions. No restriction on the genome structure considering linear and circular chromosomes is imposed. An advantage of this general model is that it leads to considerable algorithmic simplifications compared to other genome rearrangement models. Recently, several works concerning the DCJ operation have been published, and in particular, an algorithm was proposed to find an optimal DCJ sequence for sorting one genome into another one. Here we study the solution space of this problem and give an easy-to-compute formula that corresponds to the exact number of optimal DCJ sorting sequences for a particular subset of instances of the problem. We also give an algorithm to count the number of optimal sorting sequences for any instance of the problem. Another interesting result is the demonstration of the possibility of obtaining one optimal sorting sequence by properly replacing any pair of consecutive operations in another optimal sequence. As a consequence, any optimal sorting sequence can be obtained from one other by applying such replacements successively, but the problem of finding the shortest number of replacements between two sorting sequences is still open.

Multiple motifs regulate apical sorting of p75 via a mechanism that involves dimerization and higher-order oligomerization

PubMed Central

Youker, Robert T.; Bruns, Jennifer R.; Costa, Simone A.; Rbaibi, Youssef; Lanni, Frederick; Kashlan, Ossama B.; Teng, Haibing; Weisz, Ora A.

2013-01-01

The sorting signals that direct proteins to the apical surface of polarized epithelial cells are complex and can include posttranslational modifications, such as N- and O-linked glycosylation. Efficient apical sorting of the neurotrophin receptor p75 is dependent on its O-glycosylated membrane proximal stalk, but how this domain mediates targeting is unknown. Protein oligomerization or clustering has been suggested as a common step in the segregation of all apical proteins. Like many apical proteins, p75 forms dimers, and we hypothesized that formation of higher-order clusters mediated by p75 dimerization and interactions of the stalk facilitate its apical sorting. Using fluorescence fluctuation techniques (photon-counting histogram and number and brightness analyses) to study p75 oligomerization status in vivo, we found that wild-type p75–green fluorescent protein forms clusters in the trans-Golgi network (TGN) but not at the plasma membrane. Disruption of either the dimerization motif or the stalk domain impaired both clustering and polarized delivery. Manipulation of O-glycan processing or depletion of multiple galectins expressed in Madin-Darby canine kidney cells had no effect on p75 sorting, suggesting that the stalk domain functions as a structural prop to position other determinants in the lumenal domain of p75 for oligomerization. Additionally, a p75 mutant with intact dimerization and stalk motifs but with a dominant basolateral sorting determinant (Δ250 mutant) did not form oligomers, consistent with a requirement for clustering in apical sorting. Artificially enhancing dimerization restored clustering to the Δ250 mutant but was insufficient to reroute this mutant to the apical surface. Together these studies demonstrate that clustering in the TGN is required for normal biosynthetic apical sorting of p75 but is not by itself sufficient to reroute a protein to the apical surface in the presence of a strong basolateral sorting determinant. Our studies shed new light on the hierarchy of polarized sorting signals and on the mechanisms by which newly synthesized proteins are segregated in the TGN for eventual apical delivery. PMID:23637462

Changes in Patient Sorting to Nursing Homes under Public Reporting: Improved Patient Matching or Provider Gaming?

PubMed Central

Werner, Rachel M; Konetzka, R Tamara; Stuart, Elizabeth A; Polsky, Daniel

2011-01-01

Objective To test whether public reporting in the setting of postacute care in nursing homes results in changes in patient sorting. Data Sources/Study Setting All postacute care admissions from 2001 to 2003 in the nursing home Minimum Data Set. Study Design We test changes in patient sorting (or the changes in the illness severity of patients going to high- versus low-scoring facilities) when public reporting was initiated in nursing homes in 2002. We test for changes in sorting with respect to pain, delirium, and walking and then examine the potential roles of cream skimming and downcoding in changes in patient sorting. We use a difference-in-differences framework, taking advantage of the variation in the launch of public reporting in pilot and nonpilot states, to control for underlying trends in patient sorting. Principal Findings There was a significant change in patient sorting with respect to pain after public reporting was initiated, with high-risk patients being more likely to go to high-scoring facilities and low-risk patients more likely to go to low-scoring facilities. There was also an overall decrease in patient risk of pain with the launch of public reporting, which may be consistent with changes in documentation of pain levels (or downcoding). There was no significant change in sorting for delirium or walking. Conclusions Public reporting of nursing home quality improves matching of high-risk patients to high-quality facilities. However, efforts should be made to reduce the incentives for downcoding by nursing facilities. PMID:21105869

Microfluidic Droplet Sorting with a High Frequency Ultrasound Beam

PubMed Central

Lee, Changyang; Lee, Jungwoo; Kim, Hyung Ham; Teh, Shia-Yen; Lee, Abraham; Chung, In-Young; Park, Jae Yeong; Shung, K. Kirk

2012-01-01

This paper presents experimental results demonstrating the feasibility of high frequency ultrasonic sensing and sorting for screening single oleic acid (lipid or oil) droplets under continuous flow in a microfluidic channel. In these experiments, hydrodynamically focused lipid droplets of two different diameters (50 μm and 100 μm) are centered along the middle of the channel that is filled with deionized (DI) water. A 30 MHz lithium niobate (LiNbO3) transducer, placed outside the channel, first transmits short sensing pulses to non-invasively determine acoustic scattering properties of individual droplets that are passing through the beam’s focus. Integrated backscatter (IB) coefficients, utilized as a sorting criterion, are measured by analyzing received echo signals from each droplet. When the IB values corresponding to 100 μm droplets are obtained, a custom-built LabVIEW panel commands the transducer to emit sinusoidal burst signals to commence the sorting operation. The number of droplets tested for the sorting is 139 for 50 μm droplets and 95 for 100 μm droplets. The sensing efficiencies are estimated to be 98.6 % and 99.0 %, respectively. The sorting is carried out by applying acoustic radiation forces to 100 μm droplets to direct them towards the upper sheath flow, thus separating them from the centered droplet flow. The sorting efficiencies are 99.3 % for 50 μm droplets and 85.3 % for 100 μm droplets. The results suggest that this proposed technique has the potential to be further developed into a cost-effective and efficient cell/microparticle sorting instrument. PMID:22643737

Online sorting of recovered wood waste by automated XRF-technology: part II. Sorting efficiencies.

PubMed

Hasan, A Rasem; Solo-Gabriele, Helena; Townsend, Timothy

2011-04-01

Sorting of waste wood is an important process practiced at recycling facilities in order to detect and divert contaminants from recycled wood products. Contaminants of concern include arsenic, chromium and copper found in chemically preserved wood. The objective of this research was to evaluate the sorting efficiencies of both treated and untreated parts of the wood waste stream, and metal (As, Cr and Cu) mass recoveries by the use of automated X-ray fluorescence (XRF) systems. A full-scale system was used for experimentation. This unit consisted of an XRF-detection chamber mounted on the top of a conveyor and a pneumatic slide-way diverter which sorted wood into presumed treated and presumed untreated piles. A randomized block design was used to evaluate the operational conveyance parameters of the system, including wood feed rate and conveyor belt speed. Results indicated that online sorting efficiencies of waste wood by XRF technology were high based on number and weight of pieces (70-87% and 75-92% for treated wood and 66-97% and 68-96% for untreated wood, respectively). These sorting efficiencies achieved mass recovery for metals of 81-99% for As, 75-95% for Cu and 82-99% of Cr. The incorrect sorting of wood was attributed almost equally to deficiencies in the detection and conveyance/diversion systems. Even with its deficiencies, the system was capable of producing a recyclable portion that met residential soil quality levels established for Florida, for an infeed that contained 5% of treated wood. Copyright © 2010 Elsevier Ltd. All rights reserved.

A cell sorting and trapping microfluidic device with an interdigital channel

NASA Astrophysics Data System (ADS)

Tu, Jing; Qiao, Yi; Xu, Minghua; Li, Junji; Liang, Fupeng; Duan, Mengqin; Ju, An; Lu, Zuhong

2016-12-01

The growing interest in cell sorting and trapping is driving the demand for high performance technologies. Using labeling techniques or external forces, cells can be identified by a series of methods. However, all of these methods require complicated systems with expensive devices. Based on inherent differences in cellular morphology, cells can be sorted by specific structures in microfluidic devices. The weir filter is a basic and efficient cell sorting and trapping structure. However, in some existing weir devices, because of cell deformability and high flow velocity in gaps, trapped cells may become stuck or even pass through the gaps. Here, we designed and fabricated a microfluidic device with interdigital channels for cell sorting and trapping. The chip consisted of a sheet of silicone elastomer polydimethylsiloxane and a sheet of glass. A square-wave-like weir was designed in the middle of the channel, comprising the interdigital channels. The square-wave pattern extended the weir length by three times with the channel width remaining constant. Compared with a straight weir, this structure exhibited a notably higher trapping capacity. Interdigital channels provided more space to slow down the rate of the pressure decrease, which prevented the cells from becoming stuck in the gaps. Sorting a mixture K562 and blood cells to trap cells demonstrated the efficiency of the chip with the interdigital channel to sort and trap large and less deformable cells. With stable and efficient cell sorting and trapping abilities, the chip with an interdigital channel may be widely applied in scientific research fields.

A probability-based multi-cycle sorting method for 4D-MRI: A simulation study.

PubMed

Liang, Xiao; Yin, Fang-Fang; Liu, Yilin; Cai, Jing

2016-12-01

To develop a novel probability-based sorting method capable of generating multiple breathing cycles of 4D-MRI images and to evaluate performance of this new method by comparing with conventional phase-based methods in terms of image quality and tumor motion measurement. Based on previous findings that breathing motion probability density function (PDF) of a single breathing cycle is dramatically different from true stabilized PDF that resulted from many breathing cycles, it is expected that a probability-based sorting method capable of generating multiple breathing cycles of 4D images may capture breathing variation information missing from conventional single-cycle sorting methods. The overall idea is to identify a few main breathing cycles (and their corresponding weightings) that can best represent the main breathing patterns of the patient and then reconstruct a set of 4D images for each of the identified main breathing cycles. This method is implemented in three steps: (1) The breathing signal is decomposed into individual breathing cycles, characterized by amplitude, and period; (2) individual breathing cycles are grouped based on amplitude and period to determine the main breathing cycles. If a group contains more than 10% of all breathing cycles in a breathing signal, it is determined as a main breathing pattern group and is represented by the average of individual breathing cycles in the group; (3) for each main breathing cycle, a set of 4D images is reconstructed using a result-driven sorting method adapted from our previous study. The probability-based sorting method was first tested on 26 patients' breathing signals to evaluate its feasibility of improving target motion PDF. The new method was subsequently tested for a sequential image acquisition scheme on the 4D digital extended cardiac torso (XCAT) phantom. Performance of the probability-based and conventional sorting methods was evaluated in terms of target volume precision and accuracy as measured by the 4D images, and also the accuracy of average intensity projection (AIP) of 4D images. Probability-based sorting showed improved similarity of breathing motion PDF from 4D images to reference PDF compared to single cycle sorting, indicated by the significant increase in Dice similarity coefficient (DSC) (probability-based sorting, DSC = 0.89 ± 0.03, and single cycle sorting, DSC = 0.83 ± 0.05, p-value <0.001). Based on the simulation study on XCAT, the probability-based method outperforms the conventional phase-based methods in qualitative evaluation on motion artifacts and quantitative evaluation on tumor volume precision and accuracy and accuracy of AIP of the 4D images. In this paper the authors demonstrated the feasibility of a novel probability-based multicycle 4D image sorting method. The authors' preliminary results showed that the new method can improve the accuracy of tumor motion PDF and the AIP of 4D images, presenting potential advantages over the conventional phase-based sorting method for radiation therapy motion management.

Sorting waves and associated eigenvalues

NASA Astrophysics Data System (ADS)

Carbonari, Costanza; Colombini, Marco; Solari, Luca

2017-04-01

The presence of mixed sediment always characterizes gravel bed rivers. Sorting processes take place during bed load transport of heterogeneous sediment mixtures. The two main elements necessary to the occurrence of sorting are the heterogeneous character of sediments and the presence of an active sediment transport. When these two key ingredients are simultaneously present, the segregation of bed material is consistently detected both in the field [7] and in laboratory [3] observations. In heterogeneous sediment transport, bed altimetric variations and sorting always coexist and both mechanisms are independently capable of driving the formation of morphological patterns. Indeed, consistent patterns of longitudinal and transverse sorting are identified almost ubiquitously. In some cases, such as bar formation [2] and channel bends [5], sorting acts as a stabilizing effect and therefore the dominant mechanism driving pattern formation is associated with bed altimetric variations. In other cases, such as longitudinal streaks, sorting enhances system instability and can therefore be considered the prevailing mechanism. Bedload sheets, first observed by Khunle and Southard [1], represent another classic example of a morphological pattern essentially triggered by sorting, as theoretical [4] and experimental [3] results suggested. These sorting waves cause strong spatial and temporal fluctuations of bedload transport rate typical observed in gravel bed rivers. The problem of bed load transport of a sediment mixture is formulated in the framework of a 1D linear stability analysis. The base state consists of a uniform flow in an infinitely wide channel with active bed load transport. The behaviour of the eigenvalues associated with fluid motion, bed evolution and sorting processes in the space of the significant flow and sediment parameters is analysed. A comparison is attempted with the results of the theoretical analysis of Seminara Colombini and Parker [4] and Stecca, Siviglia and Blom [6]. [1] Kuhnle, R.A. and Southard, J.B. 1988. Bed Load Transport Fluctuations in a Gravel Bed Laboratory Channel. Water Resources Research, 24(2), 247-260. [2] Lanzoni, S. and Tubino, M. 1999. Grain sorting and bar instability. Journal of Fluid Mechanics. 393, 149-174. [3] Recking, A., Frey, P., Paquier, A. and Belleudy, P. 2009. An experimental investigation of mechanisms involved in bed load sheet production and migration. Journal of Geophysical Research, 114, F03010. [4] Seminara, G., Colombini, M. and Parker, G. 1996. Nearly pure sorting waves and formation of bedload sheets. Journal of Fluid Mechanics. 312, (1996), 253-278. [5] Seminara, G., Solari, L. and Tubino, M. 1997. Finite amplitude scour and grain sorting in wide channel bends. XXVII IAHR Congress, San Francisco, 1445-1450. [6] Stecca, G., Siviglia, A. and Blom, A. 2014. Mathematical analysis of the Saint-Venant-Hirano model for mixed-sediment morphodynamics. Water Resources Research, 50, 7563-7589. [7] Whiting, P.J., Dietrich, W.E., Leopold, L. B., Drake, T. G. and Shreve, R.L. 1988. Bedload sheets in heterogeneous sediment. Geology, 16, 105-108.

The Use of Binary Search Trees in External Distribution Sorting.

ERIC Educational Resources Information Center

Cooper, David; Lynch, Michael F.

1984-01-01

Suggests new method of external distribution called tree partitioning that involves use of binary tree to split incoming file into successively smaller partitions for internal sorting. Number of disc accesses during a tree-partitioning sort were calculated in simulation using files extracted from British National Bibliography catalog files. (19…

Competition, Student Sorting and Performance Gains in Local Education Markets: The Dutch Secondary Sector

ERIC Educational Resources Information Center

Cabus, Sofie; Cornelisz, Ilja

2017-01-01

This article empirically examines the implications of competition among Dutch secondary schools: (1) regarding the sorting of students by performance levels in schools at the beginning of secondary education; and (2) regarding performance gains in the secondary school career, controlling for the aforementioned sorting patterns. We used data from…

Card-Sorting Usability Tests of the WMU Libraries' Web Site

ERIC Educational Resources Information Center

Whang, Michael

2008-01-01

This article describes the card-sorting techniques used by several academic libraries, reports and discusses the results of card-sorting usability tests of the Western Michigan University Libraries' Web site, and reveals how the WMU libraries incorporated the findings into a new Web site redesign, setting the design direction early on. The article…

Automatic Color Sorting System for Hardwood Edge-Glued Panel Parts

Treesearch

Richard W. Conners; D.Earl Kline; Philip A. Araman

1996-01-01

The color sorting of edge-glued panel parts is becoming more important in the manufacture of hardwood products. Consumers, while admiring the natural appearance of hardwoods, do not like excessive color variation across product surfaces. Color uniformity is particularly important today because of the popularity of lightly stained products. Unfortunately, color sorting...

Raman-Activated Droplet Sorting (RADS) for Label-Free High-Throughput Screening of Microalgal Single-Cells.

PubMed

Wang, Xixian; Ren, Lihui; Su, Yetian; Ji, Yuetong; Liu, Yaoping; Li, Chunyu; Li, Xunrong; Zhang, Yi; Wang, Wei; Hu, Qiang; Han, Danxiang; Xu, Jian; Ma, Bo

2017-11-21

Raman-activated cell sorting (RACS) has attracted increasing interest, yet throughput remains one major factor limiting its broader application. Here we present an integrated Raman-activated droplet sorting (RADS) microfluidic system for functional screening of live cells in a label-free and high-throughput manner, by employing AXT-synthetic industrial microalga Haematococcus pluvialis (H. pluvialis) as a model. Raman microspectroscopy analysis of individual cells is carried out prior to their microdroplet encapsulation, which is then directly coupled to DEP-based droplet sorting. To validate the system, H. pluvialis cells containing different levels of AXT were mixed and underwent RADS. Those AXT-hyperproducing cells were sorted with an accuracy of 98.3%, an enrichment ratio of eight folds, and a throughput of ∼260 cells/min. Of the RADS-sorted cells, 92.7% remained alive and able to proliferate, which is equivalent to the unsorted cells. Thus, the RADS achieves a much higher throughput than existing RACS systems, preserves the vitality of cells, and facilitates seamless coupling with downstream manipulations such as single-cell sequencing and cultivation.

Impact of Reminders on Children’s Cognitive Flexibility, Intrinsic Motivation, and Mood Depends on Who Provides the Reminders

PubMed Central

Qu, Li; Ong, Jing Y.

2016-01-01

Reminding children to think about alternatives is a strategy adults often use to promote children’s cognitive flexibility, as well as children’s engagement in and enjoyment of the task. The current study investigated whether the impacts of reminders on kindergarten children’s cognitive flexibility, intrinsic motivation, and mood are moderated by who provides the reminders. Eighty-three healthy 5-year-old kindergarten children were randomly assigned to 2 (Reminder: no reminders vs. Reminders) × 2 (Agent: Tester vs. Partner) conditions. Children’s cognitive flexibility was measured via the Block Sorting Task (Garton and Pratt, 2001; Fawcett and Garton, 2005). Children reported their motivation and mood before Block Sorting, after practicing for Block Sorting, and after the actual Block Sorting. Children’s intrinsic motivation was measured by evaluating children’s choices during a period of free play after Block Sorting. The results revealed that, depending on who provides the reminders, reminding children of alternatives can influence kindergarten children’s performance on Block Sorting, children’s intrinsic motivation, and children’s self-reported mood. PMID:26779058

Phosphatidylinositol-4-kinase type II alpha contains an AP-3-sorting motif and a kinase domain that are both required for endosome traffic.

PubMed

Craige, Branch; Salazar, Gloria; Faundez, Victor

2008-04-01

The adaptor complex 3 (AP-3) targets membrane proteins from endosomes to lysosomes, lysosome-related organelles and synaptic vesicles. Phosphatidylinositol-4-kinase type II alpha (PI4KIIalpha) is one of several proteins possessing catalytic domains that regulate AP-3-dependent sorting. Here we present evidence that PI4KIIalpha uniquely behaves both as a membrane protein cargo as well as an enzymatic regulator of adaptor function. In fact, AP-3 and PI4KIIalpha form a complex that requires a dileucine-sorting motif present in PI4KIIalpha. Mutagenesis of either the PI4KIIalpha-sorting motif or its kinase-active site indicates that both are necessary to interact with AP-3 and properly localize PI4KIIalpha to LAMP-1-positive endosomes. Similarly, both the kinase activity and the sorting signal present in PI4KIIalpha are necessary to rescue endosomal PI4KIIalpha siRNA-induced mutant phenotypes. We propose a mechanism whereby adaptors use canonical sorting motifs to selectively recruit a regulatory enzymatic activity to restricted membrane domains.

IAP-Based Cell Sorting Results in Homogeneous Transplantable Dopaminergic Precursor Cells Derived from Human Pluripotent Stem Cells.

PubMed

Lehnen, Daniela; Barral, Serena; Cardoso, Tiago; Grealish, Shane; Heuer, Andreas; Smiyakin, Andrej; Kirkeby, Agnete; Kollet, Jutta; Cremer, Harold; Parmar, Malin; Bosio, Andreas; Knöbel, Sebastian

2017-10-10

Human pluripotent stem cell (hPSC)-derived mesencephalic dopaminergic (mesDA) neurons can relieve motor deficits in animal models of Parkinson's disease (PD). Clinical translation of differentiation protocols requires standardization of production procedures, and surface-marker-based cell sorting is considered instrumental for reproducible generation of defined cell products. Here, we demonstrate that integrin-associated protein (IAP) is a cell surface marker suitable for enrichment of hPSC-derived mesDA progenitor cells. Immunomagnetically sorted IAP + mesDA progenitors showed increased expression of ventral midbrain floor plate markers, lacked expression of pluripotency markers, and differentiated into mature dopaminergic (DA) neurons in vitro. Intrastriatal transplantation of IAP + cells sorted at day 16 of differentiation in a rat model of PD resulted in functional recovery. Grafts from sorted IAP + mesDA progenitors were more homogeneous in size and DA neuron density. Thus, we suggest IAP-based sorting for reproducible prospective enrichment of mesDA progenitor cells in clinical cell replacement strategies. Copyright © 2017 Miltenyi Biotec GmbH. Published by Elsevier Inc. All rights reserved.

Sorting signed permutations by inversions in O(nlogn) time.

PubMed

Swenson, Krister M; Rajan, Vaibhav; Lin, Yu; Moret, Bernard M E

2010-03-01

The study of genomic inversions (or reversals) has been a mainstay of computational genomics for nearly 20 years. After the initial breakthrough of Hannenhalli and Pevzner, who gave the first polynomial-time algorithm for sorting signed permutations by inversions, improved algorithms have been designed, culminating with an optimal linear-time algorithm for computing the inversion distance and a subquadratic algorithm for providing a shortest sequence of inversions--also known as sorting by inversions. Remaining open was the question of whether sorting by inversions could be done in O(nlogn) time. In this article, we present a qualified answer to this question, by providing two new sorting algorithms, a simple and fast randomized algorithm and a deterministic refinement. The deterministic algorithm runs in time O(nlogn + kn), where k is a data-dependent parameter. We provide the results of extensive experiments showing that both the average and the standard deviation for k are small constants, independent of the size of the permutation. We conclude (but do not prove) that almost all signed permutations can be sorted by inversions in O(nlogn) time.