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

An overview of in-orbit radiometric calibration of typical satellite sensors

NASA Astrophysics Data System (ADS)

Zhou, G. Q.; Li, C. Y.; Yue, T.; Jiang, L. J.; Liu, N.; Sun, Y.; Li, M. Y.

2015-06-01

This paper reviews the development of in-orbit radiometric calibration methods in the past 40 years. It summarizes the development of in-orbit radiometric calibration technology of typical satellite sensors in the visible/near-infrared bands and the thermal infrared band. Focuses on the visible/near-infrared bands radiometric calibration method including: Lamp calibration and solar radiationbased calibration. Summarizes the calibration technology of Landsat series satellite sensors including MSS, TM, ETM+, OLI, TIRS; SPOT series satellite sensors including HRV, HRS. In addition to the above sensors, there are also summarizing ALI which was equipped on EO-1, IRMSS which was equipped on CBERS series satellite. Comparing the in-orbit radiometric calibration technology of different periods but the same type satellite sensors analyzes the similarities and differences of calibration technology. Meanwhile summarizes the in-orbit radiometric calibration technology in the same periods but different country satellite sensors advantages and disadvantages of calibration technology.

Radiometric cytolysis inhibition assay, a new rapid test for neutralizing antibodies to intact and trypsin-cleaved poliovirus

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

Hovi, T.; Roivainen, M.

1989-04-01

We have developed a new rapid test, the radiometric cytolysis inhibition assay (RACINA), for the determination of neutralizing poliovirus antibodies. HeLa cells prelabeled with /sup 51/Cr, (/sup 3/H)leucine, or, preferentially, with (/sup 3/H)uridine are used as sensitive quantitative indicators of residual infectious virus. Both suspensions and monolayer cultures of the indicator cells can be used. Neutralization of a fraction of a high-titer virus preparation can be scored after the first replication cycle at 8 to 10 h. By lowering the incubation temperature to 30/degree/C, the completion of the cytolysis due to the first replication cycle of poliovirus was delayed beyondmore » 21 h. This makes it possible to use the RACINA, unlike the standard microneutralization assay, for measuring antibodies to trypsin-cleaved polioviruses. The RACINA was found to be as sensitive as and more reproducible than the standard microneutralization assay in the measurement of neutralizing poliovirus antibodies. The RACINA is a rapid and reliable test for neutralizing antibodies and in principle it may be applicable for quantitation of neutralizing antibodies to other cytolytic agents as well.« less

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.

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).

Verification of the radiometric map of the Czech Republic.

PubMed

Matolín, Milan

2017-01-01

The radiometric map of the Czech Republic is based on uniform regional airborne radiometric total count measurements (1957-1959) which covered 100% of the country. The airborne radiometric instrument was calibrated to a 226 Ra point source. The calibration facility for field gamma-ray spectrometers, established in the Czech Republic in 1975, significantly contributed to the subsequent radiometric data standardization. In the 1990's, the original analogue airborne radiometric data were digitized and using the method of back-calibration (IAEA, 2003) converted to dose rate. The map of terrestrial gamma radiation expressed in dose rate (nGy/h) was published on the scale 1:500,000 in 1995. Terrestrial radiation in the Czech Republic, formed by magmatic, sedimentary and metamorphic rocks of Proterozoic to Quaternary age, ranges mostly from 6 to 245 nGy/h, with a mean of 65.6 ± 19.0 nGy/h. The elevated terrestrial radiation in the Czech Republic, in comparison to the global dose rate average of 54 nGy/h, reflects an enhanced content of natural radioactive elements in the rocks. The 1995 published radiometric map of the Czech Republic was successively studied and verified by additional ground gamma-ray spectrometric measurements and by comparison to radiometric maps of Germany, Poland and Slovakia in border zones. A ground dose rate intercomparison measurement under participation of foreign and domestic professional institutions revealed mutual dose rate deviations about 20 nGy/h and more due to differing technical parameters of applied radiometric instruments. Studies and verification of the radiometric map of the Czech Republic illustrate the magnitude of current deviations in dose rate data. This gained experience can assist in harmonization of dose rate data on the European scale. Copyright © 2016 Elsevier Ltd. All rights reserved.

Lessons learned from the AIRS pre-flight radiometric calibration

NASA Astrophysics Data System (ADS)

Pagano, Thomas S.; Aumann, Hartmut H.; Weiler, Margie

2013-09-01

The Atmospheric Infrared Sounder (AIRS) instrument flies on the NASA Aqua satellite and measures the upwelling hyperspectral earth radiance in the spectral range of 3.7-15.4 μm with a nominal ground resolution at nadir of 13.5 km. The AIRS spectra are achieved using a temperature controlled grating spectrometer and HgCdTe infrared linear arrays providing 2378 channels with a nominal spectral resolution of approximately 1200. The AIRS pre-flight tests that impact the radiometric calibration include a full system radiometric response (linearity), polarization response, and response vs scan angle (RVS). We re-derive the AIRS instrument radiometric calibration coefficients from the pre-flight polarization measurements, the response vs scan (RVS) angle tests as well as the linearity tests, and a recent lunar roll test that allowed the AIRS to view the moon. The data and method for deriving the coefficients is discussed in detail and the resulting values compared amongst the different tests. Finally, we examine the residual errors in the reconstruction of the external calibrator blackbody radiances and the efficacy of a new radiometric uncertainty model. Results show the radiometric calibration of AIRS to be excellent and the radiometric uncertainty model does a reasonable job of characterizing the errors.

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.

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.

Radiometric performance of the Voyager cameras

NASA Technical Reports Server (NTRS)

Danielson, G. E.; Kupferman, P. N.; Johnson, T. V.; Soderblom, L. A.

1981-01-01

The Voyager Imaging Experiment provided high-quality data of Jupiter and the Galilean satellites with the two flyby trajectories in March and July of 1979. Moderately accurate radiometric measurements have been made using these data. This paper evaluates the radiometric results and describes the inflight and ground geometric and radiometric correction factors. The radiometric quantities of intensity I and geometric albedo I/F are derived, and scaling factors for each of the filters are tabulated for correcting the 'calibrated' data from the Image Processing Laboratory at JPL. In addition, the key characteristics of both Voyager I and Voyager 2 cameras are tabulated.

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.

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

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.

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-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.

Preliminary Evaluation of the Radiometric Calibration of LANDSAT-4 Thematic Mapper Data by the Canada Centre for Remote Sensing

NASA Technical Reports Server (NTRS)

Murphy, J.; Park, W.; Fitzgerald, A.

1985-01-01

The radiometric characteristics of the LANDSAT-4 TM sensor are being studied with a view to developing absolute and relative radiometric calibration procedures. Preliminary results from several different approaches to the relative correction of all detectors within each band are reported. Topics covered include: the radiometric correction method; absolute calibration; the relative radiometric calibration algorithm; relative gain and offset calibration; relative gain and offset observations; and residual radiometric stripping.

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 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…

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 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).

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.

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

Evaluation on Radiometric Capability of Chinese Optical Satellite Sensors

PubMed Central

Yang, Aixia; Zhong, Bo; Wu, Shanlong; Liu, Qinhuo

2017-01-01

The radiometric capability of on-orbit sensors should be updated on time due to changes induced by space environmental factors and instrument aging. Some sensors, such as Moderate Resolution Imaging Spectroradiometer (MODIS), have onboard calibrators, which enable real-time calibration. However, most Chinese remote sensing satellite sensors lack onboard calibrators. Their radiometric calibrations have been updated once a year based on a vicarious calibration procedure, which has affected the applications of the data. Therefore, a full evaluation of the sensors’ radiometric capabilities is essential before quantitative applications can be made. In this study, a comprehensive procedure for evaluating the radiometric capability of several Chinese optical satellite sensors is proposed. In this procedure, long-term radiometric stability and radiometric accuracy are the two major indicators for radiometric evaluation. The radiometric temporal stability is analyzed by the tendency of long-term top-of-atmosphere (TOA) reflectance variation; the radiometric accuracy is determined by comparison with the TOA reflectance from MODIS after spectrally matching. Three Chinese sensors including the Charge-Coupled Device (CCD) camera onboard Huan Jing 1 satellite (HJ-1), as well as the Visible and Infrared Radiometer (VIRR) and Medium-Resolution Spectral Imager (MERSI) onboard the Feng Yun 3 satellite (FY-3) are evaluated in reflective bands based on this procedure. The results are reasonable, and thus can provide reliable reference for the sensors’ application, and as such will promote the development of Chinese satellite data. PMID:28117745

Evaluation on Radiometric Capability of Chinese Optical Satellite Sensors.

PubMed

Yang, Aixia; Zhong, Bo; Wu, Shanlong; Liu, Qinhuo

2017-01-22

The radiometric capability of on-orbit sensors should be updated on time due to changes induced by space environmental factors and instrument aging. Some sensors, such as Moderate Resolution Imaging Spectroradiometer (MODIS), have onboard calibrators, which enable real-time calibration. However, most Chinese remote sensing satellite sensors lack onboard calibrators. Their radiometric calibrations have been updated once a year based on a vicarious calibration procedure, which has affected the applications of the data. Therefore, a full evaluation of the sensors' radiometric capabilities is essential before quantitative applications can be made. In this study, a comprehensive procedure for evaluating the radiometric capability of several Chinese optical satellite sensors is proposed. In this procedure, long-term radiometric stability and radiometric accuracy are the two major indicators for radiometric evaluation. The radiometric temporal stability is analyzed by the tendency of long-term top-of-atmosphere (TOA) reflectance variation; the radiometric accuracy is determined by comparison with the TOA reflectance from MODIS after spectrally matching. Three Chinese sensors including the Charge-Coupled Device (CCD) camera onboard Huan Jing 1 satellite (HJ-1), as well as the Visible and Infrared Radiometer (VIRR) and Medium-Resolution Spectral Imager (MERSI) onboard the Feng Yun 3 satellite (FY-3) are evaluated in reflective bands based on this procedure. The results are reasonable, and thus can provide reliable reference for the sensors' application, and as such will promote the development of Chinese satellite data.

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.

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.

Prospects for the application of radiometric methods in the measurement of two-phase flows

NASA Astrophysics Data System (ADS)

Zych, Marcin

2018-06-01

The article constitutes an overview of the application of radiometric methods in the research of two-phase flows: liquid-solid particles and liquid-gas flows. The methods which were used were described on the basis of the experiments which were conducted in the Water Laboratory of the Wrocław University of Environmental and Life Sciences and in the Sedimentological Laboratory of the Faculty of Geology, Geophysics and Environmental Protection, AGH-UST in Kraków. The advanced mathematical methods for the analysis of signals from scintillation probes that were applied enable the acquisition of a number of parameters associated with the flowing two-phase mixture, such as: average velocities of the particular phases, concentration of the solid phase, and void fraction for a liquid-gas mixture. Despite the fact that the application of radioactive sources requires considerable carefulness and a number of state permits, in many cases these sources become useful in the experiments which are presented.

Radiometric packaging of uncooled bolometric infrared focal plane arrays

NASA Astrophysics Data System (ADS)

García-Blanco, Sonia; Pope, Timothy; Côté, Patrice; Leclerc, Mélanie; Ngo Phong, Linh; Châteauneuf, François

2017-11-01

INO has a wide experience in the design and fabrication of different kinds of microbolometer focal plane arrays (FPAs). In particular, a 512x3 pixel microbolometer FPA has been selected as the sensor for the New Infrared Sensor Technology (NIRST) instrument, one of the payloads of the SACD/Aquarius mission. In order to make the absolute temperature measurements necessary for many infrared Earth observation applications, the microbolometer FPA must be integrated into a package offering a very stable thermal environment. The radiometric packaging technology developed at INO presents an innovative approach since it was conceived to be modular and adaptable for the packaging of different microbolometer FPAs and for different sets of assembly requirements without need for requalification of the assembly process. The development of the radiometric packaging technology has broadened the position of INO as a supplier of radiometric detector modules integrating FPAs of microbolometers inside a radiometric package capable of achieving the requirements of different space missions. This paper gives an overview of the design of INO's radiometric package. Key performance parameters are also discussed and the test campaign conducted with the radiometric package is presented.

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.

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.

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.

Method for radiometric calibration of an endoscope's camera and light source

NASA Astrophysics Data System (ADS)

Rai, Lav; Higgins, William E.

2008-03-01

An endoscope is a commonly used instrument for performing minimally invasive visual examination of the tissues inside the body. A physician uses the endoscopic video images to identify tissue abnormalities. The images, however, are highly dependent on the optical properties of the endoscope and its orientation and location with respect to the tissue structure. The analysis of endoscopic video images is, therefore, purely subjective. Studies suggest that the fusion of endoscopic video images (providing color and texture information) with virtual endoscopic views (providing structural information) can be useful for assessing various pathologies for several applications: (1) surgical simulation, training, and pedagogy; (2) the creation of a database for pathologies; and (3) the building of patient-specific models. Such fusion requires both geometric and radiometric alignment of endoscopic video images in the texture space. Inconsistent estimates of texture/color of the tissue surface result in seams when multiple endoscopic video images are combined together. This paper (1) identifies the endoscope-dependent variables to be calibrated for objective and consistent estimation of surface texture/color and (2) presents an integrated set of methods to measure them. Results show that the calibration method can be successfully used to estimate objective color/texture values for simple planar scenes, whereas uncalibrated endoscopes performed very poorly for the same tests.

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.

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.

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.

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.

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.

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.

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

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

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.

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

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.

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.

New Sentinel-2 radiometric validation approaches (SEOM program)

NASA Astrophysics Data System (ADS)

Bruniquel, Véronique; Lamquin, Nicolas; Ferron, Stéphane; Govaerts, Yves; Woolliams, Emma; Dilo, Arta; Gascon, Ferran

2016-04-01

SEOM is an ESA program element whose one of the objectives aims at launching state-of-the-art studies for the scientific exploitation of operational missions. In the frame of this program, ESA awarded ACRI-ST and its partners Rayference and National Physical Laboratory (NPL) early 2016 for a R&D study on the development and intercomparison of algorithms for validating the Sentinel-2 radiometric L1 data products beyond the baseline algorithms used operationally in the frame of the S2 Mission Performance Centre. In this context, several algorithms have been proposed and are currently in development: The first one is based on the exploitation of Deep Convective Cloud (DCC) observations over ocean. This method allows an inter-band radiometry validation from the blue to the NIR (typically from B1 to B8a) from a reference band already validated for example with the well-known Rayleigh method. Due to their physical properties, DCCs appear from the remote sensing point of view to have bright and cold tops and they can be used as invariant targets to monitor the radiometric response degradation of reflective solar bands. The DCC approach is statistical i.e. the method shall be applied on a large number of measurements to derive reliable statistics and decrease the impact of the perturbing contributors. The second radiometric validation method is based on the exploitation of matchups combining both concomitant in-situ measurements and Sentinel-2 observations. The in-situ measurements which are used here correspond to measurements acquired in the frame of the RadCalNet networks. The validation is performed for the Sentinel-2 bands similar to the bands of the instruments equipping the validation site. The measurements from the Cimel CE 318 12-filters BRDF Sun Photometer installed recently in the Gobabeb site near the Namib desert are used for this method. A comprehensive verification of the calibration requires an analysis of MSI radiances over the full dynamic range

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

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.

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.

Rapid, Standardized Method for Determination of Mycobacterium tuberculosis Drug Susceptibility by Use of Mycolic Acid Analysis▿

PubMed Central

Parrish, Nicole; Osterhout, Gerard; Dionne, Kim; Sweeney, Amy; Kwiatkowski, Nicole; Carroll, Karen; Jost, Kenneth C.; Dick, James

2007-01-01

Multidrug-resistant (MDR) Mycobacterium tuberculosis and extrensively drug-resistant (XDR) M. tuberculosis are emerging public health threats whose threats are compounded by the fact that current techniques for testing the susceptibility of M. tuberculosis require several days to weeks to complete. We investigated the use of high-performance liquid chromatography (HPLC)-based quantitation of mycolic acids as a means of rapidly determining drug resistance and susceptibility in M. tuberculosis. Standard susceptibility testing and determination of the MICs of drug-susceptible (n = 26) and drug-resistant M. tuberculosis strains, including MDR M. tuberculosis strains (n = 34), were performed by using the Bactec radiometric growth system as the reference method. The HPLC-based susceptibilities of the current first-line drugs, isoniazid (INH), rifampin (RIF), ethambutol (EMB), and pyrazinamide (PZA), were determined. The vials were incubated for 72 h, and aliquots were removed for HPLC analysis by using the Sherlock mycobacterial identification system. HPLC quantitation of total mycolic acid peaks (TMAPs) was performed with treated and untreated cultures. At 72 h, the levels of agreement of the HPLC method with the reference method were 99.5% for INH, EMB, and PZA and 98.7% for RIF. The inter- and intra-assay reproducibilities varied by drug, with an average precision of 13.4%. In summary, quantitation of TMAPs is a rapid, sensitive, and accurate method for antibiotic susceptibility testing of all first-line drugs currently used against M. tuberculosis and offers the potential of providing susceptibility testing results within hours, rather than days or weeks, for clinical M. tuberculosis isolates. PMID:17913928

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

Radiometric characterization of hyperspectral imagers using multispectral sensors

NASA Astrophysics Data System (ADS)

McCorkel, Joel; Thome, Kurt; Leisso, Nathan; Anderson, Nikolaus; Czapla-Myers, Jeff

2009-08-01

The Remote Sensing Group (RSG) at the University of Arizona has a long history of using ground-based test sites for the calibration of airborne and satellite based sensors. Often, ground-truth measurements at these tests sites are not always successful due to weather and funding availability. Therefore, RSG has also employed automated ground instrument approaches and cross-calibration methods to verify the radiometric calibration of a sensor. The goal in the cross-calibration method is to transfer the calibration of a well-known sensor to that of a different sensor. This work studies the feasibility of determining the radiometric calibration of a hyperspectral imager using multispectral imagery. The work relies on the Moderate Resolution Imaging Spectroradiometer (MODIS) as a reference for the hyperspectral sensor Hyperion. Test sites used for comparisons are Railroad Valley in Nevada and a portion of the Libyan Desert in North Africa. Hyperion bands are compared to MODIS by band averaging Hyperion's high spectral resolution data with the relative spectral response of MODIS. The results compare cross-calibration scenarios that differ in image acquisition coincidence, test site used for the calibration, and reference sensor. Cross-calibration results are presented that show agreement between the use of coincident and non-coincident image pairs within 2% in most bands as well as similar agreement between results that employ the different MODIS sensors as a reference.

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.

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.

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.

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.

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 novel method for destriping of OCM-2 data and radiometric performance analysis for improved ocean color data products

NASA Astrophysics Data System (ADS)

Singh, Rakesh Kumar; Shanmugam, Palanisamy

2018-06-01

Despite the capability of Ocean Color Monitor aboard Oceansat-2 satellite to provide frequent, high-spatial resolution, visible and near-infrared images for scientific research on coastal zones and climate data records over the global ocean, the generation of science quality ocean color products from OCM-2 data has been hampered by serious vertical striping artifacts and poor calibration of detectors. These along-track stripes are the results of variations in the relative response of the individual detectors of the OCM-2 CCD array. The random unsystematic stripes and bandings on the scene edges affect both visual interpretation and radiometric integrity of remotely sensed data, contribute to confusion in the aerosol correction process, and multiply and propagate into higher level ocean color products generated by atmospheric correction and bio-optical algorithms. Despite a number of destriping algorithms reported in the literature, complete removal of stripes without residual effects and signal distortion in both low- and high-level products is still challenging. Here, a new operational algorithm has been developed that employs an inverted gaussian function to estimate error fraction parameters, which are uncorrelated and vary in spatial, spectral and temporal domains. The algorithm is tested on a large number of OCM-2 scenes from Arabian Sea and Bay of Bengal waters contaminated with severe stripes. The destriping effectiveness of this approach is then evaluated by means of various qualitative and quantitative analyses, and by comparison with the results of the previously reported method. Clearly, the present method is more effective in terms of removing the stripe noise while preserving the radiometric integrity of the destriped OCM-2 data. Furthermore, a preliminary time-dependent calibration of the OCM-2 sensor is performed with several match-up in-situ data to evaluate its radiometric performance for ocean color applications. OCM-2 derived water

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-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.

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.

Ground-Based Radiometric Measurements of Slant Path Attenuation in the V/W Bands

DTIC Science & Technology

2016-04-01

GROUND-BASED RADIOMETRIC MEASUREMENTS OF SLANT PATH ATTENUATION IN THE V/W BANDS APRIL 2016 FINAL TECHNICAL REPORT APPROVED FOR PUBLIC RELEASE...2. REPORT TYPE FINAL TECHNICAL REPORT 3. DATES COVERED (From - To) OCT 2012 – SEP 2015 4. TITLE AND SUBTITLE GROUND-BASED RADIOMETRIC MEASUREMENTS ...SUPPLEMENTARY NOTES 14. ABSTRACT Ground-based radiometric techniques were applied to measure the slant path attenuation cumulative distribution function to

Radiometric Normalization of Large Airborne Image Data Sets Acquired by Different Sensor Types

NASA Astrophysics Data System (ADS)

Gehrke, S.; Beshah, B. T.

2016-06-01

Generating seamless mosaics of aerial images is a particularly challenging task when the mosaic comprises a large number of im-ages, collected over longer periods of time and with different sensors under varying imaging conditions. Such large mosaics typically consist of very heterogeneous image data, both spatially (different terrain types and atmosphere) and temporally (unstable atmo-spheric properties and even changes in land coverage). We present a new radiometric normalization or, respectively, radiometric aerial triangulation approach that takes advantage of our knowledge about each sensor's properties. The current implementation supports medium and large format airborne imaging sensors of the Leica Geosystems family, namely the ADS line-scanner as well as DMC and RCD frame sensors. A hierarchical modelling - with parameters for the overall mosaic, the sensor type, different flight sessions, strips and individual images - allows for adaptation to each sensor's geometric and radiometric properties. Additional parameters at different hierarchy levels can compensate radiome-tric differences of various origins to compensate for shortcomings of the preceding radiometric sensor calibration as well as BRDF and atmospheric corrections. The final, relative normalization is based on radiometric tie points in overlapping images, absolute radiometric control points and image statistics. It is computed in a global least squares adjustment for the entire mosaic by altering each image's histogram using a location-dependent mathematical model. This model involves contrast and brightness corrections at radiometric fix points with bilinear interpolation for corrections in-between. The distribution of the radiometry fixes is adaptive to each image and generally increases with image size, hence enabling optimal local adaptation even for very long image strips as typi-cally captured by a line-scanner sensor. The normalization approach is implemented in HxMap software. It has been

Radiometric Characterization of Hyperspectral Imagers using Multispectral Sensors

NASA Technical Reports Server (NTRS)

McCorkel, Joel; Kurt, Thome; Leisso, Nathan; Anderson, Nikolaus; Czapla-Myers, Jeff

2009-01-01

The Remote Sensing Group (RSG) at the University of Arizona has a long history of using ground-based test sites for the calibration of airborne and satellite based sensors. Often, ground-truth measurements at these test sites are not always successful due to weather and funding availability. Therefore, RSG has also automated ground instrument approaches and cross-calibration methods to verify the radiometric calibration of a sensor. The goal in the cross-calibration method is to transfer the calibration of a well-known sensor to that of a different sensor, This work studies the feasibility of determining the radiometric calibration of a hyperspectral imager using multispectral a imagery. The work relies on the Moderate Resolution Imaging Spectroradiometer (M0DIS) as a reference for the hyperspectral sensor Hyperion. Test sites used for comparisons are Railroad Valley in Nevada and a portion of the Libyan Desert in North Africa. Hyperion bands are compared to MODIS by band averaging Hyperion's high spectral resolution data with the relative spectral response of M0DlS. The results compare cross-calibration scenarios that differ in image acquisition coincidence, test site used for the calibration, and reference sensor. Cross-calibration results are presented that show agreement between the use of coincident and non-coincident image pairs within 2% in most brands as well as similar agreement between results that employ the different MODIS sensors as a reference.

[Rapid prototyping: a very promising method].

PubMed

Haverman, T M; Karagozoglu, K H; Prins, H-J; Schulten, E A J M; Forouzanfar, T

2013-03-01

Rapid prototyping is a method which makes it possible to produce a three-dimensional model based on two-dimensional imaging. Various rapid prototyping methods are available for modelling, such as stereolithography, selective laser sintering, direct laser metal sintering, two-photon polymerization, laminated object manufacturing, three-dimensional printing, three-dimensional plotting, polyjet inkjet technology,fused deposition modelling, vacuum casting and milling. The various methods currently being used in the biomedical sector differ in production, materials and properties of the three-dimensional model which is produced. Rapid prototyping is mainly usedforpreoperative planning, simulation, education, and research into and development of bioengineering possibilities.

Ground-Based Microwave Radiometric Remote Sensing of the Tropical Atmosphere

NASA Astrophysics Data System (ADS)

Han, Yong

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 temperatures to the desired atmospheric variables. The mathematical inversion problem, in a linear form, was viewed in terms of the theory of linear algebra. Several 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. During this experiment, the radiometer was calibrated by using tipping curve and radiosonde data as well as measurements of the radiation from a blackbody absorber. A linear statistical method was first 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, it was shown that the radiometric measurements with experimental noises added no more profile information to the inversion than that which was available from a climatological mean. Although successful retrievals of the geopotential heights were made, it was shown that they were determined mainly by the surface pressure measurements. The reasons why the radiometer did not contribute to the retrievals of temperature profiles and geopotential heights were discussed. A method

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.

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.;

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.

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.

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.

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.

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.

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.

Radiometric dates from Alaska: A 1975 compilation

USGS Publications Warehouse

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

1975-01-01

The following table of radiometric dates from Alaska includes published material through 1972 as well as some selected later data. The table includes 726 mineral and whole-rock dates determined by the K-Ar, Rb-Sr, fission-track U-Pb, and Pb-alpha techniques.The data are organized in alphabetical order of the 1:250,000 scale quadrangles in which the dated rocks are located. The latitude and longitude of each sample are given. In addition, each sample is located on a 1:250,000 quadrangle map by a grid system. The initial point of the grid is taken as the southwest corner of the quadrangle and the location of the sample is measured in inches east and inches north from that corner, e.g., "156E 126N" indicated 15.6 inches east and 12.6 inches north of the southwest corner of the quadrangle. Zeroes in the location columns for some dates indicate that accurate locations are not available.Rock type, dating method, mineral dated, radiometric age, sample identification number, and reference are also listed where possible. Short comments, mostly geographic locality names, are given for some dates. These comments have been taken from the original references.Sample identification numbers beginning with "AA" or "BB" have been assigned arbitrarily in cases where sample numbers were not assigned in the original references. Abbreviations are explained in the appendix at the end of table 1.

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

Innovative rapid construction/reconstruction methods.

DOT National Transportation Integrated Search

2005-07-01

Innovative construction and reconstruction methods provide the opportunity to significantly reduce the time of roadway projects while maintaining the necessary quality of workmanship. The need for these rapid methods stems from the increase in ...

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.

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.

A scoping review of rapid review methods.

PubMed

Tricco, Andrea C; Antony, Jesmin; Zarin, Wasifa; Strifler, Lisa; Ghassemi, Marco; Ivory, John; Perrier, Laure; Hutton, Brian; Moher, David; Straus, Sharon E

2015-09-16

Rapid reviews are a form of knowledge synthesis in which components of the systematic review process are simplified or omitted to produce information in a timely manner. Although numerous centers are conducting rapid reviews internationally, few studies have examined the methodological characteristics of rapid reviews. We aimed to examine articles, books, and reports that evaluated, compared, used or described rapid reviews or methods through a scoping review. MEDLINE, EMBASE, the Cochrane Library, internet websites of rapid review producers, and reference lists were searched to identify articles for inclusion. Two reviewers independently screened literature search results and abstracted data from included studies. Descriptive analysis was conducted. We included 100 articles plus one companion report that were published between 1997 and 2013. The studies were categorized as 84 application papers, seven development papers, six impact papers, and four comparison papers (one was included in two categories). The rapid reviews were conducted between 1 and 12 months, predominantly in Europe (58 %) and North America (20 %). The included studies failed to report 6 % to 73 % of the specific systematic review steps examined. Fifty unique rapid review methods were identified; 16 methods occurred more than once. Streamlined methods that were used in the 82 rapid reviews included limiting the literature search to published literature (24 %) or one database (2 %), limiting inclusion criteria by date (68 %) or language (49 %), having one person screen and another verify or screen excluded studies (6 %), having one person abstract data and another verify (23 %), not conducting risk of bias/quality appraisal (7 %) or having only one reviewer conduct the quality appraisal (7 %), and presenting results as a narrative summary (78 %). Four case studies were identified that compared the results of rapid reviews to systematic reviews. Three studies found that the conclusions between

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.

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.

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.

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.

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.

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.

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...

A design of an on-orbit radiometric calibration device for high dynamic range infrared remote sensors

NASA Astrophysics Data System (ADS)

Sheng, Yicheng; Jin, Weiqi; Dun, Xiong; Zhou, Feng; Xiao, Si

2017-10-01

With the demand of quantitative remote sensing technology growing, high reliability as well as high accuracy radiometric calibration technology, especially the on-orbit radiometric calibration device has become an essential orientation in term of quantitative remote sensing technology. In recent years, global launches of remote sensing satellites are equipped with innovative on-orbit radiometric calibration devices. In order to meet the requirements of covering a very wide dynamic range and no-shielding radiometric calibration system, we designed a projection-type radiometric calibration device for high dynamic range sensors based on the Schmidt telescope system. In this internal radiometric calibration device, we select the EF-8530 light source as the calibration blackbody. EF-8530 is a high emittance Nichrome (Ni-Cr) reference source. It can operate in steady or pulsed state mode at a peak temperature of 973K. The irradiance from the source was projected to the IRFPA. The irradiance needs to ensure that the IRFPA can obtain different amplitude of the uniform irradiance through the narrow IR passbands and cover the very wide dynamic range. Combining the internal on-orbit radiometric calibration device with the specially designed adaptive radiometric calibration algorithms, an on-orbit dynamic non-uniformity correction can be accomplished without blocking the optical beam from outside the telescope. The design optimizes optics, source design, and power supply electronics for irradiance accuracy and uniformity. The internal on-orbit radiometric calibration device not only satisfies a series of indexes such as stability, accuracy, large dynamic range and uniformity of irradiance, but also has the advantages of short heating and cooling time, small volume, lightweight, low power consumption and many other features. It can realize the fast and efficient relative radiometric calibration without shielding the field of view. The device can applied to the design and

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.

Radiometric Cross-Calibration of the HJ-1B IRS in the Thermal Infrared Spectral Band

NASA Astrophysics Data System (ADS)

Sun, K.

2012-12-01

The natural calamities occur continually, environment pollution and destruction in a severe position on the earth presently, which restricts societal and economic development. The satellite remote sensing technology has an important effect on improving surveillance ability of environment pollution and natural calamities. The radiometric calibration is precondition of quantitative remote sensing; which accuracy decides quality of the retrieval parameters. Since the China Environment Satellite (HJ-1A/B) has been launched successfully on September 6th, 2008, it has made an important role in the economic development of China. The satellite has four infrared bands; and one of it is thermal infrared. With application fields of quantitative remote sensing in china, finding appropriate calibration method becomes more and more important. Many kinds of independent methods can be used to do the absolute radiometric calibration. In this paper, according to the characteristic of thermal infrared channel of HJ-1B thermal infrared multi-spectral camera, the thermal infrared spectral band of HJ-1B IRS was calibrated using cross-calibration methods based on MODIS data. Firstly, the corresponding bands of the two sensors were obtained. Secondly, the MONDTRAN was run to analyze the influences of different spectral response, satellite view zenith angle, atmosphere condition and temperature on the match factor. In the end, their band match factor was calculated in different temperature, considering the dissimilar band response of the match bands. Seven images of Lake Qinghai in different time were chosen as the calibration data. On the basis of radiance of MODIS and match factor, the IRS radiance was calculated. And then the calibration coefficients were obtained by linearly regressing the radiance and the DN value. We compared the result of this cross-calibration with that of the onboard blackbody calibration, which consistency was good.The maximum difference of brightness temperature

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.

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.

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.

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)

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.

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

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.

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.

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.

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.

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.

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).

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 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.

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

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.

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.

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

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.

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%.

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.

Rapid Method for Sodium Hydroxide/Sodium Peroxide Fusion ...

EPA Pesticide Factsheets

Technical Fact Sheet Analysis Purpose: Qualitative analysis Technique: Alpha spectrometry Method Developed for: Plutonium-238 and plutonium-239 in water and air filters Method Selected for: SAM lists this method as a pre-treatment technique supporting analysis of refractory radioisotopic forms of plutonium in drinking water and air filters using the following qualitative techniques: • Rapid methods for acid or fusion digestion • Rapid Radiochemical Method for Plutonium-238 and Plutonium 239/240 in Building Materials for Environmental Remediation Following Radiological Incidents. Summary of subject analytical method which will be posted to the SAM website to allow access to the method.

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.

Rapid Radiochemical Methods for Selected Radionuclides

EPA Pesticide Factsheets

The rapid methods documents are supplement guidance in a planned series designed to present radioanalytical laboratory personnel, Incident Commanders (and their designees), and other field response personnel.

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.

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.

Rapid Radiochemical Methods for Asphalt Paving Material ...

EPA Pesticide Factsheets

Technical Brief Validated rapid radiochemical methods for alpha and beta emitters in solid matrices that are commonly encountered in urban environments were previously unavailable for public use by responding laboratories. A lack of tested rapid methods would delay the quick determination of contamination levels and the assessment of acceptable site-specific exposure levels. Of special concern are matrices with rough and porous surfaces, which allow the movement of radioactive material deep into the building material making it difficult to detect. This research focuses on methods that address preparation, radiochemical separation, and analysis of asphalt paving materials and asphalt roofing shingles. These matrices, common to outdoor environments, challenge the capability and capacity of very experienced radiochemistry laboratories. Generally, routine sample preparation and dissolution techniques produce liquid samples (representative of the original sample material) that can be processed using available radiochemical methods. The asphalt materials are especially difficult because they do not readily lend themselves to these routine sample preparation and dissolution techniques. The HSRP and ORIA coordinate radiological reference laboratory priorities and activities in conjunction with HSRP’s Partner Process. As part of the collaboration, the HSRP worked with ORIA to publish rapid radioanalytical methods for selected radionuclides in building material matrice

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.

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.

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.

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

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.

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.

Application and sensitivity investigation of Fourier transforms for microwave radiometric inversions

NASA Technical Reports Server (NTRS)

Holmes, J. J.; Balanis, C. A.

1974-01-01

Existing microwave radiometer technology now provides a suitable method for remote determination of the ocean surface's absolute brightness temperature. To extract the brightness temperature of the water from the antenna temperature equation, an unstable Fredholm integral equation of the first kind was solved. Fast Fourier Transform techniques were used to invert the integral after it is placed into a cross-correlation form. Application and verification of the methods to a two-dimensional modeling of a laboratory wave tank system were included. The instability of the Fredholm equation was then demonstrated and a restoration procedure was included which smooths the resulting oscillations. With the recent availability and advances of Fast Fourier Transform techniques, the method presented becomes very attractive in the evaluation of large quantities of data. Actual radiometric measurements of sea water are inverted using the restoration method, incorporating the advantages of the Fast Fourier Transform algorithm for computations.

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

Creating the Infrastructure for Rapid Application Development and Processing Response to the HIRDLS Radiance Anomaly

NASA Astrophysics Data System (ADS)

Cavanaugh, C.; Gille, J.; Francis, G.; Nardi, B.; Hannigan, J.; McInerney, J.; Krinsky, C.; Barnett, J.; Dean, V.; Craig, C.

2005-12-01

The High Resolution Dynamics Limb Sounder (HIRDLS) instrument onboard the NASA Aura spacecraft experienced a rupture of the thermal blanketing material (Kapton) during the rapid depressurization of launch. The Kapton draped over the HIRDLS scan mirror, severely limiting the aperture through which HIRDLS views space and Earth's atmospheric limb. In order for HIRDLS to achieve its intended measurement goals, rapid characterization of the anomaly, and rapid recovery from it were required. The recovery centered around a new processing module inserted into the standard HIRDLS processing scheme, with a goal of minimizing the effect of the anomaly on the already existing processing modules. We describe the software infrastructure on which the new processing module was built, and how that infrastructure allows for rapid application development and processing response. The scope of the infrastructure spans three distinct anomaly recovery steps and the means for their intercommunication. Each of the three recovery steps (removing the Kapton-induced oscillation in the radiometric signal, removing the Kapton signal contamination upon the radiometric signal, and correcting for the partially-obscured atmospheric view) is completely modularized and insulated from the other steps, allowing focused and rapid application development towards a specific step, and neutralizing unintended inter-step influences, thus greatly shortening the design-development-test lifecycle. The intercommunication is also completely modularized and has a simple interface to which the three recovery steps adhere, allowing easy modification and replacement of specific recovery scenarios, thereby heightening the processing response.

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.

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 surveys in underground environment

NASA Astrophysics Data System (ADS)

Bochiolo, Massimo; Chiozzi, Paolo; Verdoya, Massimo; Pasquale, Vincenzo

2010-05-01

Due to their ability to travel through the air for several metres, gamma-rays emitted from natural radioactive elements can be successfully used in surveys carried out both with airborne and ground equipments. Besides the concentration of the radio-elements contained in rocks and soils and the intrinsic characteristics of the gamma-ray detector, the detected count rate depends on the solid angle around the spectrometer. On a flat outcrop, ground spectrometry detects the radiation ideally produced by a cylindrical mass of rock of about two metres in diameter and thickness of about half a meter. Under these geometrical conditions, the natural radioactivity can be easily evaluated. With operating conditions different from the standard ones, such as at the edge of an escarpment, the count rate halves because of the missing material, whereas in the vicinity of a rock wall the count rate will increase. In underground environment, the recorded count rate may even double and the in situ assessment of the concentration of radio-elements may be rather difficult, even if the ratios between the different radio-elements may not be affected. We tested the applicability of gamma-ray spectrometry for rapid assessment of the potential hazard levels related to radon and radiation dose rate in underground environment. A mine shaft, located in a zone of uranium enrichment in Liguria (Italy), has been investigated. A preliminary ground radiometric survey was carried out to define the extent of the ore deposit. Then, the radiometric investigation was focussed on the mine shaft. Due to rock mass above the shaft vault, the background gamma radiation can be considered of negligible influence on measurements. In underground surveys, besides deviations from a flat geometry, factors controlling radon exhalation, emanation and stagnation, such as fractures, water leakage and the presence of ventilation, should be carefully examined. We attempted to evaluate these control factors and collected

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.;

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

Absolute Radiometric Calibration of EUNIS-06

NASA Technical Reports Server (NTRS)

Thomas, R. J.; Rabin, D. M.; Kent, B. J.; Paustian, W.

2007-01-01

The Extreme-Ultraviolet Normal-Incidence Spectrometer (EUNIS) is a soundingrocket payload that obtains imaged high-resolution spectra of individual solar features, providing information about the Sun's corona and upper transition region. Shortly after its successful initial flight last year, a complete end-to-end calibration was carried out to determine the instrument's absolute radiometric response over its Longwave bandpass of 300 - 370A. The measurements were done at the Rutherford-Appleton Laboratory (RAL) in England, using the same vacuum facility and EUV radiation source used in the pre-flight calibrations of both SOHO/CDS and Hinode/EIS, as well as in three post-flight calibrations of our SERTS sounding rocket payload, the precursor to EUNIS. The unique radiation source provided by the Physikalisch-Technische Bundesanstalt (PTB) had been calibrated to an absolute accuracy of 7% (l-sigma) at 12 wavelengths covering our bandpass directly against the Berlin electron storage ring BESSY, which is itself a primary radiometric source standard. Scans of the EUNIS aperture were made to determine the instrument's absolute spectral sensitivity to +- 25%, considering all sources of error, and demonstrate that EUNIS-06 was the most sensitive solar E W spectrometer yet flown. The results will be matched against prior calibrations which relied on combining measurements of individual optical components, and on comparisons with theoretically predicted 'insensitive' line ratios. Coordinated observations were made during the EUNIS-06 flight by SOHO/CDS and EIT that will allow re-calibrations of those instruments as well. In addition, future EUNIS flights will provide similar calibration updates for TRACE, Hinode/EIS, and STEREO/SECCHI/EUVI.

RAPID METHOD FOR DETERMINATION OF RADIOSTRONTIUM IN EMERGENCY MILK SAMPLES

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

Maxwell, S.; Culligan, B.

2008-07-17

A new rapid separation method for radiostrontium in emergency milk samples was developed at the Savannah River Site (SRS) Environmental Bioassay Laboratory (Aiken, SC, USA) that will allow rapid separation and measurement of Sr-90 within 8 hours. The new method uses calcium phosphate precipitation, nitric acid dissolution of the precipitate to coagulate residual fat/proteins and a rapid strontium separation using Sr Resin (Eichrom Technologies, Darien, IL, USA) with vacuum-assisted flow rates. The method is much faster than previous method that use calcination or cation exchange pretreatment, has excellent chemical recovery, and effectively removes beta interferences. When a 100 ml samplemore » aliquot is used, the method has a detection limit of 0.5 Bq/L, well below generic emergency action levels.« less

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;

REVIEW OF RAPID METHODS FOR ASSESSING WETLAND CONDITION

EPA Science Inventory

We evaluated over 40 wetland rapid assessment methods developed for a variety of purposes for their use in the assessment of ecological integrity or ecosystem condition. Four criteria were used to screen methods: 1) the method can be used to measure condition, 2) it is truly rap...

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.

Radiometric dating of the Siloam Tunnel, Jerusalem.

PubMed

Frumkin, Amos; Shimron, Aryeh; Rosenbaum, Jeff

2003-09-11

The historical credibility of texts from the Bible is often debated when compared with Iron Age archaeological finds (refs. 1, 2 and references therein). Modern scientific methods may, in principle, be used to independently date structures that seem to be mentioned in the biblical text, to evaluate its historical authenticity. In reality, however, this approach is extremely difficult because of poor archaeological preservation, uncertainty in identification, scarcity of datable materials, and restricted scientific access into well-identified worship sites. Because of these problems, no well-identified Biblical structure has been radiometrically dated until now. Here we report radiocarbon and U-Th dating of the Siloam Tunnel, proving its Iron Age II date; we conclude that the Biblical text presents an accurate historic record of the Siloam Tunnel's construction. Being one of the longest ancient water tunnels lacking intermediate shafts, dating the Siloam Tunnel is a key to determining where and when this technological breakthrough took place. Siloam Tunnel dating also refutes a claim that the tunnel was constructed in the second century bc.

A comparison of radiometric correction techniques in the evaluation of the relationship between LST and NDVI in Landsat imagery.

PubMed

Tan, Kok Chooi; Lim, Hwee San; Matjafri, Mohd Zubir; Abdullah, Khiruddin

2012-06-01

Atmospheric corrections for multi-temporal optical satellite images are necessary, especially in change detection analyses, such as normalized difference vegetation index (NDVI) rationing. Abrupt change detection analysis using remote-sensing techniques requires radiometric congruity and atmospheric correction to monitor terrestrial surfaces over time. Two atmospheric correction methods were used for this study: relative radiometric normalization and the simplified method for atmospheric correction (SMAC) in the solar spectrum. A multi-temporal data set consisting of two sets of Landsat images from the period between 1991 and 2002 of Penang Island, Malaysia, was used to compare NDVI maps, which were generated using the proposed atmospheric correction methods. Land surface temperature (LST) was retrieved using ATCOR3_T in PCI Geomatica 10.1 image processing software. Linear regression analysis was utilized to analyze the relationship between NDVI and LST. This study reveals that both of the proposed atmospheric correction methods yielded high accuracy through examination of the linear correlation coefficients. To check for the accuracy of the equation obtained through linear regression analysis for every single satellite image, 20 points were randomly chosen. The results showed that the SMAC method yielded a constant value (in terms of error) to predict the NDVI value from linear regression analysis-derived equation. The errors (average) from both proposed atmospheric correction methods were less than 10%.

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.

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.

[Principle of LAMP method--a simple and rapid gene amplification method].

PubMed

Ushikubo, Hiroshi

2004-06-01

So far nucleic acid test (NAT) has been employed in various fields, including infectious disease diagnoses. However, due to its complicated procedures and relatively high cost, it has not been widely utilized in many actual diagnostic applications. We have therefore developed a simple and rapid gene amplification technology, Loop-mediated Isothermal Amplification (LAMP) method, which has shown prominent results of surpassing the performance of the conventional gene amplification methods. LAMP method acquires three main features: (1) all reaction can be carried out under isothermal conditions; (2) the amplification efficiency is extremely high and tremendous amount of amplification products can be obtained; and (3) the reaction is highly specific. Furthermore, developed from the standard LAMP method, a rapid LAMP method, by adding in the loop primers, can reduce the amplification time from the previous 1 hour to less than 30 minutes. Enormous amount of white precipitate of magnesium pyrophosphate is produced as a by-product of the amplification, therefore, direct visual detection is possible without using any reaction indicators and detection equipments. We believe LAMP technology, with the integration of these features, can rightly apply to clinical genetic testing, food and environmental analysis, as well as NAT in different fields.

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.

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).

Validation of Rapid Radiochemical Method for Californium ...

EPA Pesticide Factsheets

Technical Brief In the event of a radiological/nuclear contamination event, the response community would need tools and methodologies to rapidly assess the nature and the extent of contamination. To characterize a radiologically contaminated outdoor area and to inform risk assessment, large numbers of environmental samples would be collected and analyzed over a short period of time. To address the challenge of quickly providing analytical results to the field, the U.S. EPA developed a robust analytical method. This method allows response officials to characterize contaminated areas and to assess the effectiveness of remediation efforts, both rapidly and accurately, in the intermediate and late phases of environmental cleanup. Improvement in sample processing and analysis leads to increased laboratory capacity to handle the analysis of a large number of samples following the intentional or unintentional release of a radiological/nuclear contaminant.

JPSS-1 VIIRS Pre-Launch Radiometric Performance

NASA Technical Reports Server (NTRS)

Oudrari, Hassan; McIntire, Jeff; Xiong, Xiaoxiong; Butler, James; Efremova, Boryana; Ji, Jack; Lee, Shihyan; Schwarting, Tom

2015-01-01

The Visible Infrared Imaging Radiometer Suite (VIIRS) on-board the first Joint Polar Satellite System (JPSS) completed its sensor level testing on December 2014. The JPSS-1 (J1) mission is scheduled to launch in December 2016, and will be very similar to the Suomi-National Polar-orbiting Partnership (SNPP) mission. VIIRS instrument was designed to provide measurements of the globe twice daily. It is a wide-swath (3,040 kilometers) cross-track scanning radiometer with spatial resolutions of 370 and 740 meters at nadir for imaging and moderate bands, respectively. It covers the wavelength spectrum from reflective to long-wave infrared through 22 spectral bands [0.412 microns to 12.01 microns]. VIIRS observations are used to generate 22 environmental data products (EDRs). This paper will briefly describe J1 VIIRS characterization and calibration performance and methodologies executed during the pre-launch testing phases by the independent government team, to generate the at-launch baseline radiometric performance, and the metrics needed to populate the sensor data record (SDR) Look-Up-Tables (LUTs). This paper will also provide an assessment of the sensor pre-launch radiometric performance, such as the sensor signal to noise ratios (SNRs), dynamic range, reflective and emissive bands calibration performance, polarization sensitivity, bands spectral performance, response-vs-scan (RVS), near field and stray light responses. A set of performance metrics generated during the pre-launch testing program will be compared to the SNPP VIIRS pre-launch performance.

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

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.

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

Evaluation of forest decontamination using radiometric measurements.

PubMed

Cresswell, Alan J; Kato, Hiroaki; Onda, Yuichi; Nanba, Kenji

2016-11-01

An experiment has been conducted to evaluate the additional dose reduction by clear felling contaminated forestry in Fukushima Prefecture, Japan, and using the timber to cover the areas with wood chips. A portable gamma spectrometry system, comprising a backpack containing a 3 × 3″ NaI(Tl) detector with digital spectrometer and GPS receiver, has been used to map dose rate and radionuclide activity concentrations before, after and at stages during this experiment. The data show the effect of the different stages of the experiment on dose rate at different locations around the site. The spectrometric data have allowed the assessment of the contributions of natural and anthropogenic radionuclides to the dose rate at different parts of the site before and after the experiment. This has clearly demonstrated the value of radiometric methods in evaluating remediation, and the effect of other environmental processes. The value of spectrometric methods which directly measure radionuclide concentrations has also been shown, especially through the identification of the contribution of natural and anthropogenic activity to the measured dose rate. The experiment has shown that clearing trees and applying wood chips can reduce dose rates by 10-15% beyond that achieved by just clearing the forest litter and natural redistribution of radiocaesium. Copyright © 2016 Elsevier Ltd. All rights reserved.

A novel method for rapid in vitro radiobioassay

NASA Astrophysics Data System (ADS)

Crawford, Evan Bogert

Rapid and accurate analysis of internal human exposure to radionuclides is essential to the effective triage and treatment of citizens who have possibly been exposed to radioactive materials in the environment. The two most likely scenarios in which a large number of citizens would be exposed are the detonation of a radiation dispersal device (RDD, "dirty bomb") or the accidental release of an isotope from an industrial source such as a radioisotopic thermal generator (RTG). In the event of the release and dispersion of radioactive materials into the environment in a large city, the entire population of the city -- including all commuting workers and tourists -- would have to be rapidly tested, both to satisfy the psychological needs of the citizens who were exposed to the mental trauma of a possible radiation dose, and to satisfy the immediate medical needs of those who received the highest doses and greatest levels of internal contamination -- those who would best benefit from rapid, intensive medical care. In this research a prototype rapid screening method to screen urine samples for the presence of up to five isotopes, both individually and in a mixture, has been developed. The isotopes used to develop this method are Co-60, Sr-90, Cs-137, Pu-238, and Am-241. This method avoids time-intensive chemical separations via the preparation and counting of a single sample on multiple detectors, and analyzing the spectra for isotope-specific markers. A rapid liquid-liquid separation using an organic extractive scintillator can be used to help quantify the activity of the alpha-emitting isotopes. The method provides quantifiable results in less than five minutes for the activity of beta/gamma-emitting isotopes when present in the sample at the intervention level as defined by the Centers for Disease Control and Prevention (CDC), and quantifiable results for the activity levels of alpha-emitting isotopes present at their respective intervention levels in approximately 30

Methods and systems for rapid prototyping of high density circuits

DOEpatents

Palmer, Jeremy A [Albuquerque, NM; Davis, Donald W [Albuquerque, NM; Chavez, Bart D [Albuquerque, NM; Gallegos, Phillip L [Albuquerque, NM; Wicker, Ryan B [El Paso, TX; Medina, Francisco R [El Paso, TX

2008-09-02

A preferred embodiment provides, for example, a system and method of integrating fluid media dispensing technology such as direct-write (DW) technologies with rapid prototyping (RP) technologies such as stereolithography (SL) to provide increased micro-fabrication and micro-stereolithography. A preferred embodiment of the present invention also provides, for example, a system and method for Rapid Prototyping High Density Circuit (RPHDC) manufacturing of solderless connectors and pilot devices with terminal geometries that are compatible with DW mechanisms and reduce contact resistance where the electrical system is encapsulated within structural members and manual electrical connections are eliminated in favor of automated DW traces. A preferred embodiment further provides, for example, a method of rapid prototyping comprising: fabricating a part layer using stereolithography and depositing thermally curable media onto the part layer using a fluid dispensing apparatus.

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

Rapid-estimation method for assessing scour at highway bridges

USGS Publications Warehouse

Holnbeck, Stephen R.

1998-01-01

A method was developed by the U.S. Geological Survey for rapid estimation of scour at highway bridges using limited site data and analytical procedures to estimate pier, abutment, and contraction scour depths. The basis for the method was a procedure recommended by the Federal Highway Administration for conducting detailed scour investigations, commonly referred to as the Level 2 method. Using pier, abutment, and contraction scour results obtained from Level 2 investigations at 122 sites in 10 States, envelope curves and graphical relations were developed that enable determination of scour-depth estimates at most bridge sites in a matter of a few hours. Rather than using complex hydraulic variables, surrogate variables more easily obtained in the field were related to calculated scour-depth data from Level 2 studies. The method was tested by having several experienced individuals apply the method in the field, and results were compared among the individuals and with previous detailed analyses performed for the sites. Results indicated that the variability in predicted scour depth among individuals applying the method generally was within an acceptable range, and that conservatively greater scour depths generally were obtained by the rapid-estimation method compared to the Level 2 method. The rapid-estimation method is considered most applicable for conducting limited-detail scour assessments and as a screening tool to determine those bridge sites that may require more detailed analysis. The method is designed to be applied only by a qualified professional possessing knowledge and experience in the fields of bridge scour, hydraulics, and flood hydrology, and having specific expertise with the Level 2 method.

Rapid Method for Sodium Hydroxide Fusion of Asphalt ...

EPA Pesticide Factsheets

Technical Brief--Addendum to Selected Analytical Methods (SAM) 2012 Rapid method developed for analysis of Americium-241 (241Am), plutonium-238 (238Pu), plutonium-239 (239Pu), radium-226 (226Ra), strontium-90 (90Sr), uranium-234 (234U), uranium-235 (235U) and uranium-238 (238U) in asphalt roofing material samples

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.

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.)

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.

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.

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

Thematic mapper: detailed radiometric and geometric characteristics

USGS Publications Warehouse

Kieffer, Hugh

1983-01-01

Those radiometric characteristics of the Landsat 4 Thematic Mapper (TM) that can be established without absolute calibration of spectral data have been examined. Subscenes of radiometric all raw data (B-data) were examined on an individual detector basis: areas of uniform radiance were used to characterize subtle radiometric differences and noise problems. A variety of anomalies have been discovered with magnitude of a few digital levels or less: the only problem not addressable by ground processing is irregular width of the digital levels. Essentially all of this non-ideal performance is incorporated in the fully processed (P-type) images, but disguised by the geometric resampling procedure. The overall performance of the Thematic Mapper is a great improvement over previous Landsat scanners. The effective resolution in radiance is degraded by about a factor of two by irregular width of the digital levels. Several detectors have a change of gain with a period of several scans, the largest effect is about 4%. These detectors appear to switch between two response levels during scan direction reversal; there is no apparent periodicity to these changes. This can cause small apparent difference between forward and reverse scans for portions of an image. The high-frequency noise level of each detector was characterized by the standard deviation of the first derivative in the sample direction across a flat field. Coherent sinusoidal noise patterns were determined using one-dimensional Fourier transforms. A "stitching" pattern in Band 1 has a period of 13.8 samples with a peak-to-peak amplitude ranging from 1 to 5 DN. Noise with a period of 3.24 samples is pronounced for most detectors in band 1, to a lesser extent in bands 2, 3, and 4, and below background noise levels in bands 5, 6, and 7. The geometric fidelity of the GSFC film writer used for Thematic Mapper (TM) images was assessed by measurement with accuracy bette than three micrometers of a test grid. A set of 55

Scalable Method to Produce Biodegradable Nanoparticles that Rapidly Penetrate Human Mucus

PubMed Central

Xu, Qingguo; Boylan, Nicholas J.; Cai, Shutian; Miao, Bolong; Patel, Himatkumar; Hanes, Justin

2013-01-01

Mucus typically traps and rapidly removes foreign particles from the airways, gastrointestinal tract, nasopharynx, female reproductive tract and the surface of the eye. Nanoparticles capable of rapid penetration through mucus can potentially avoid rapid clearance, and open significant opportunities for controlled drug delivery at mucosal surfaces. Here, we report an industrially scalable emulsification method to produce biodegradable mucus-penetrating particles (MPP). The emulsification of diblock copolymers of poly(lactic-co-glycolic acid) and polyethylene glycol (PLGA-PEG) using low molecular weight (MW) emulsifiers forms dense brush PEG coatings on nanoparticles that allow rapid nanoparticle penetration through fresh undiluted human mucus. In comparison, conventional high MW emulsifiers, such as polyvinyl alcohol (PVA), interrupts the PEG coating on nanoparticles, resulting in their immobilization in mucus owing to adhesive interactions with mucus mesh elements. PLGA-PEG nanoparticles with a wide range of PEG MW (1, 2, 5, and 10 kDa), prepared by the emulsification method using low MW emulsifiers, all rapidly penetrated mucus. A range of drugs, from hydrophobic small molecules to hydrohilic large biologics, can be efficiently loaded into biodegradable MPP using the method described. This readily scalable method should facilitate the production of MPP products for mucosal drug delivery, as well as potentially longer-circulating particles following intravenous administration. PMID:23751567

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.

A rapid and easy method for the DNA extraction from Cryptococcus neoformans

PubMed Central

2011-01-01

DNA isolation from C. neoformans is difficult due to a thick and resistant capsule. We have optimized a new and rapid DNA isolation method for Cryptococcus using a short urea treatment followed by a rapid method using a chelex resin suspension. This procedure is simpler than previously reported methods. PMID:21777412

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.

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.

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%.

[A new method of fabricating photoelastic model by rapid prototyping].

PubMed

Fan, Li; Huang, Qing-feng; Zhang, Fu-qiang; Xia, Yin-pei

2011-10-01

To explore a novel method of fabricating the photoelastic model using rapid prototyping technique. A mandible model was made by rapid prototyping with computerized three-dimensional reconstruction, then the photoelastic model with teeth was fabricated by traditional impression duplicating and mould casting. The photoelastic model of mandible with teeth, which was fabricated indirectly by rapid prototyping, was very similar to the prototype in geometry and physical parameters. The model was of high optical sensibility and met the experimental requirements. Photoelastic model of mandible with teeth indirectly fabricated by rapid prototyping meets the photoelastic experimental requirements well.

SIMS: A Hybrid Method for Rapid Conformational Analysis

PubMed Central

Gipson, Bryant; Moll, Mark; Kavraki, Lydia E.

2013-01-01

Proteins are at the root of many biological functions, often performing complex tasks as the result of large changes in their structure. Describing the exact details of these conformational changes, however, remains a central challenge for computational biology due the enormous computational requirements of the problem. This has engendered the development of a rich variety of useful methods designed to answer specific questions at different levels of spatial, temporal, and energetic resolution. These methods fall largely into two classes: physically accurate, but computationally demanding methods and fast, approximate methods. We introduce here a new hybrid modeling tool, the Structured Intuitive Move Selector (sims), designed to bridge the divide between these two classes, while allowing the benefits of both to be seamlessly integrated into a single framework. This is achieved by applying a modern motion planning algorithm, borrowed from the field of robotics, in tandem with a well-established protein modeling library. sims can combine precise energy calculations with approximate or specialized conformational sampling routines to produce rapid, yet accurate, analysis of the large-scale conformational variability of protein systems. Several key advancements are shown, including the abstract use of generically defined moves (conformational sampling methods) and an expansive probabilistic conformational exploration. We present three example problems that sims is applied to and demonstrate a rapid solution for each. These include the automatic determination of “active” residues for the hinge-based system Cyanovirin-N, exploring conformational changes involving long-range coordinated motion between non-sequential residues in Ribose-Binding Protein, and the rapid discovery of a transient conformational state of Maltose-Binding Protein, previously only determined by Molecular Dynamics. For all cases we provide energetic validations using well-established energy

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.

[Development of sample pretreatment techniques-rapid detection coupling methods for food security analysis].

PubMed

Huang, Yichun; Ding, Weiwei; Zhang, Zhuomin; Li, Gongke

2013-07-01

This paper summarizes the recent developments of the rapid detection methods for food security, such as sensors, optical techniques, portable spectral analysis, enzyme-linked immunosorbent assay, portable gas chromatograph, etc. Additionally, the applications of these rapid detection methods coupled with sample pretreatment techniques in real food security analysis are reviewed. The coupling technique has the potential to provide references to establish the selective, precise and quantitative rapid detection methods in food security analysis.

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.

A recreation quality rapid assessment method for visitor capacity management

Treesearch

Kenneth Chilman; Stuart Schneider; Les Wadzinski

2007-01-01

A rapid assessment method for inexpensively obtaining representative samples of place-specific visitor numbers and perceptions of visit quality was tested on Niobrara National Scenic River (NSR). Similar tests have been done on national forest areas in Indiana and Illinois. The data are used in meetings focusing on visitor capacity management. The rapid assessment...

Comparison of conventional and digital radiography for radiometric differentiation of dental cements.

PubMed

Baksi, B Güniz; Ermis, R Banu

2007-10-01

To test the efficacy of conventional radiometry with indirect digital image analysis in the assessment of the relative radiopacity of dental cements used as liners or bases compared to human enamel and dentin. Disks of 15 different dental cements, 5 mm in diameter and 2 mm thick, were exposed to radiation together with 2-mm-thick disks of enamel and dentin and an aluminum step wedge. Density was evaluated by digital transmission densitometry and with the histogram function of an image analysis program following digitization of the radiographs with a flatbed scanner. A higher number of dental cements were discriminated from both dentin and enamel with conventional radiographic densitometer. All the cements examined, except Ionoseal (Voco) and Ionobond (Voco), were more radiopaque than dentin. With both methods, Chelon-Silver (3M ESPE) had the highest radiopacity and glass-ionomer cements the lowest. Radiodensity of dental cements can be differentiated with a high probability with the conventional radiometric method.

Principal Component Noise Filtering for NAST-I Radiometric Calibration

NASA Technical Reports Server (NTRS)

Tian, Jialin; Smith, William L., Sr.

2011-01-01

The National Polar-orbiting Operational Environmental Satellite System (NPOESS) Airborne Sounder Testbed- Interferometer (NAST-I) instrument is a high-resolution scanning interferometer that measures emitted thermal radiation between 3.3 and 18 microns. The NAST-I radiometric calibration is achieved using internal blackbody calibration references at ambient and hot temperatures. In this paper, we introduce a refined calibration technique that utilizes a principal component (PC) noise filter to compensate for instrument distortions and artifacts, therefore, further improve the absolute radiometric calibration accuracy. To test the procedure and estimate the PC filter noise performance, we form dependent and independent test samples using odd and even sets of blackbody spectra. To determine the optimal number of eigenvectors, the PC filter algorithm is applied to both dependent and independent blackbody spectra with a varying number of eigenvectors. The optimal number of PCs is selected so that the total root-mean-square (RMS) error is minimized. To estimate the filter noise performance, we examine four different scenarios: apply PC filtering to both dependent and independent datasets, apply PC filtering to dependent calibration data only, apply PC filtering to independent data only, and no PC filters. The independent blackbody radiances are predicted for each case and comparisons are made. The results show significant reduction in noise in the final calibrated radiances with the implementation of the PC filtering algorithm.

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.

The Use of Rapid Review Methods for the U.S. Preventive Services Task Force.

PubMed

Patnode, Carrie D; Eder, Michelle L; Walsh, Emily S; Viswanathan, Meera; Lin, Jennifer S

2018-01-01

Rapid review products are intended to synthesize available evidence in a timely fashion while still meeting the needs of healthcare decision makers. Various methods and products have been applied for rapid evidence syntheses, but no single approach has been uniformly adopted. Methods to gain efficiency and compress the review time period include focusing on a narrow clinical topic and key questions; limiting the literature search; performing single (versus dual) screening of abstracts and full-text articles for relevance; and limiting the analysis and synthesis. In order to maintain the scientific integrity, including transparency, of rapid evidence syntheses, it is imperative that procedures used to streamline standard systematic review methods are prespecified, based on sound review principles and empiric evidence when possible, and provide the end user with an accurate and comprehensive synthesis. The collection of clinical preventive service recommendations maintained by the U.S. Preventive Services Task Force, along with its commitment to rigorous methods development, provide a unique opportunity to refine, implement, and evaluate rapid evidence synthesis methods and add to an emerging evidence base on rapid review methods. This paper summarizes the U.S. Preventive Services Task Force's use of rapid review methodology, its criteria for selecting topics for rapid evidence syntheses, and proposed methods to streamline the review process. Copyright © 2018 American Journal of Preventive Medicine. All rights reserved.

A Rapid Method for Measuring Strontium-90 Activity in Crops in China

NASA Astrophysics Data System (ADS)

Pan, Lingjing Pan; Yu, Guobing; Wen, Deyun; Chen, Zhi; Sheng, Liusi; Liu, Chung-King; Xu, X. George

2017-09-01

A rapid method for measuring Sr-90 activity in crop ashes is presented. Liquid scintillation counting, combined with ion exchange columns 4`, 4"(5")-di-t-butylcyclohexane-18-crown-6, is used to determine the activity of Sr-90 in crops. The yields of chemical procedure are quantified using gravimetric analysis. The conventional method that uses ion-exchange resin with HDEHP could not completely remove all the bismuth when comparatively large lead and bismuth exist in the samples. This is overcome by the rapid method. The chemical yield of this method is about 60% and the MDA for Sr-90 is found to be 2:32 Bq/kg. The whole procedure together with using spectrum analysis to determine the activity only takes about one day, which is really a large improvement compared with the conventional method. A modified conventional method is also described here to verify the value of the rapid one. These two methods can meet di_erent needs of daily monitoring and emergency situation.

Radiometric Calibration of the Earth Observing System's Imaging Sensors

NASA Technical Reports Server (NTRS)

Slater, Philip N. (Principal Investigator)

1997-01-01

The work on the grant was mainly directed towards developing new, accurate, redundant methods for the in-flight, absolute radiometric calibration of satellite multispectral imaging systems and refining the accuracy of methods already in use. Initially the work was in preparation for the calibration of MODIS and HIRIS (before the development of that sensor was canceled), with the realization it would be applicable to most imaging multi- or hyper-spectral sensors provided their spatial or spectral resolutions were not too coarse. The work on the grant involved three different ground-based, in-flight calibration methods reflectance-based radiance-based and diffuse-to-global irradiance ratio used with the reflectance-based method. This continuing research had the dual advantage of: (1) developing several independent methods to create the redundancy that is essential for the identification and hopefully the elimination of systematic errors; and (2) refining the measurement techniques and algorithms that can be used not only for improving calibration accuracy but also for the reverse process of retrieving ground reflectances from calibrated remote-sensing data. The grant also provided the support necessary for us to embark on other projects such as the ratioing radiometer approach to on-board calibration (this has been further developed by SBRS as the 'solar diffuser stability monitor' and is incorporated into the most important on-board calibration system for MODIS)- another example of the work, which was a spin-off from the grant funding, was a study of solar diffuser materials. Journal citations, titles and abstracts of publications authored by faculty, staff, and students are also attached.

Picomolar quantitation of free sulfite in foods by means of [57Co]hydroxocobalamin and radiometric chromatography of [57Co]sulfitocobalamin. Method, applications and significance of coexisting sulfides.

PubMed

Beck, R A; Anes, J M; Savini, L M; Mateer, R A

2000-06-09

The concentration dependent reaction of sulfite with 57Co-labeled hydroxocobalamin (OH57CoCbl) to produce a sulfitocobalamin (SO(3)57CoCbl) adduct served as a quantification strategy for foodborne sulfite residues freely extracted into pH 5.2, 0.05 M acetate buffer. SO(3)57CoCbl was then resolved using SP-Sephadex C-25 gel chromatography and its radiometric detection allowed calculation of a standard logit plot from which unknown sulfite concentrations could be determined. The sulfite detection range was 6.0 nM-0.3 pM with respective relative standard deviations of 4.4-29.4% for 50-microl samples. Individual incidences of foodborne sulfite intolerances provoked by L-cysteine or sulfite additive use in bakery products, which remained undetected using conventional sulfite analytical methods, underscored the quantitative value of the method. The analytical significance and occurrences of detectable sulfides coexisting with foodborne sulfite residues was also addressed.

Mesoscale, Radiometrically Referenced, Multi-Temporal Hyperspectral Data for Co2 Leak Detection by Locating Spatial Variation of Biophysically Relevant Parameters

NASA Astrophysics Data System (ADS)

McCann, Cooper Patrick

Low-cost flight-based hyperspectral imaging systems have the potential to provide valuable information for ecosystem and environmental studies as well as aide in land management and land health monitoring. This thesis describes (1) a bootstrap method of producing mesoscale, radiometrically-referenced hyperspectral data using the Landsat surface reflectance (LaSRC) data product as a reference target, (2) biophysically relevant basis functions to model the reflectance spectra, (3) an unsupervised classification technique based on natural histogram splitting of these biophysically relevant parameters, and (4) local and multi-temporal anomaly detection. The bootstrap method extends standard processing techniques to remove uneven illumination conditions between flight passes, allowing the creation of radiometrically self-consistent data. Through selective spectral and spatial resampling, LaSRC data is 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 a flight on 06/02/2016 is compared with concurrently collected ground based reflectance spectra as a means of validation achieving an average error of 2.74%. Fitting reflectance spectra using basis functions, based on biophysically relevant spectral features, allows both noise and data reductions while shifting information from spectral bands to biophysical features. Histogram splitting is used to determine a clustering based on natural splittings of these fit parameters. The Indian Pines reference data enabled comparisons of the efficacy of this technique to established techniques. The splitting technique is shown to be an improvement over the ISODATA clustering technique with an overall accuracy of 34.3/19.0% before merging and 40.9/39.2% after merging. This improvement is also seen as an improvement of kappa before/after merging of 24.8/30.5 for the histogram splitting technique

Radiometric consistency assessment of hyperspectral infrared sounders

NASA Astrophysics Data System (ADS)

Wang, L.; Han, Y.; Jin, X.; Chen, Y.; Tremblay, D. A.

2015-07-01

The radiometric and spectral consistency among the Atmospheric Infrared Sounder (AIRS), the Infrared Atmospheric Sounding Interferometer (IASI), and the Cross-track Infrared Sounder (CrIS) is fundamental for the creation of long-term infrared (IR) hyperspectral radiance benchmark datasets for both inter-calibration and climate-related studies. In this study, the CrIS radiance measurements on Suomi National Polar-orbiting Partnership (SNPP) satellite are directly compared with IASI on MetOp-A and -B at the finest spectral scale and with AIRS on Aqua in 25 selected spectral regions through one year of simultaneous nadir overpass (SNO) observations to evaluate radiometric consistency of these four hyperspectral IR sounders. The spectra from different sounders are paired together through strict spatial and temporal collocation. The uniform scenes are selected by examining the collocated Visible Infrared Imaging Radiometer Suite (VIIRS) pixels. Their brightness temperature (BT) differences are then calculated by converting the spectra onto common spectral grids. The results indicate that CrIS agrees well with IASI on MetOp-A and IASI on MetOp-B at the longwave IR (LWIR) and middle-wave IR (MWIR) bands with 0.1-0.2 K differences. There are no apparent scene-dependent patterns for BT differences between CrIS and IASI for individual spectral channels. CrIS and AIRS are compared at the 25 spectral regions for both Polar and Tropical SNOs. The combined global SNO datasets indicate that, the CrIS-AIRS BT differences are less than or around 0.1 K among 21 of 25 comparison spectral regions and they range from 0.15 to 0.21 K in the remaining 4 spectral regions. CrIS-AIRS BT differences in some comparison spectral regions show weak scene-dependent features.

Radiometric consistency assessment of hyperspectral infrared sounders

NASA Astrophysics Data System (ADS)

Wang, L.; Han, Y.; Jin, X.; Chen, Y.; Tremblay, D. A.

2015-11-01

The radiometric and spectral consistency among the Atmospheric Infrared Sounder (AIRS), the Infrared Atmospheric Sounding Interferometer (IASI), and the Cross-track Infrared Sounder (CrIS) is fundamental for the creation of long-term infrared (IR) hyperspectral radiance benchmark data sets for both intercalibration and climate-related studies. In this study, the CrIS radiance measurements on Suomi National Polar-orbiting Partnership (SNPP) satellite are directly compared with IASI on MetOp-A and MetOp-B at the finest spectral scale and with AIRS on Aqua in 25 selected spectral regions through simultaneous nadir overpass (SNO) observations in 2013, to evaluate radiometric consistency of these four hyperspectral IR sounders. The spectra from different sounders are paired together through strict spatial and temporal collocation. The uniform scenes are selected by examining the collocated Visible Infrared Imaging Radiometer Suite (VIIRS) pixels. Their brightness temperature (BT) differences are then calculated by converting the spectra onto common spectral grids. The results indicate that CrIS agrees well with IASI on MetOp-A and IASI on MetOp-B at the long-wave IR (LWIR) and middle-wave IR (MWIR) bands with 0.1-0.2 K differences. There are no apparent scene-dependent patterns for BT differences between CrIS and IASI for individual spectral channels. CrIS and AIRS are compared at the 25 spectral regions for both polar and tropical SNOs. The combined global SNO data sets indicate that the CrIS-AIRS BT differences are less than or around 0.1 K among 21 of 25 spectral regions and they range from 0.15 to 0.21 K in the remaining four spectral regions. CrIS-AIRS BT differences in some comparison spectral regions show weak scene-dependent features.

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.

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

A practical method to rapidly dissolve metallic stents.

PubMed

Bradshaw, Scott H; Kennedy, Lloyd; Dexter, David F; Veinot, John P

2009-01-01

Metallic stents are commonly used in many clinical applications including peripheral vascular disease intervention, biliary obstruction, endovascular repair of aneurysms, and percutaneous coronary interventions. In the examination of vascular stent placement, it is important to determine if the stent is open or has become obstructed. This is increasingly important in the era of drug-eluting stent usage in coronary arteries. We describe a practical, rapid and cost-effective method to dissolve most metallic stents leaving the vascular and luminal tissues intact. This practical method may replace the laborious and expensive plastic embedding methods currently utilized.

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.

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.

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.

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.

Rapid methods for the detection of foodborne bacterial pathogens: principles, applications, advantages and limitations

PubMed Central

Law, Jodi Woan-Fei; Ab Mutalib, Nurul-Syakima; Chan, Kok-Gan; Lee, Learn-Han

2015-01-01

The incidence of foodborne diseases has increased over the years and resulted in major public health problem globally. Foodborne pathogens can be found in various foods and it is important to detect foodborne pathogens to provide safe food supply and to prevent foodborne diseases. The conventional methods used to detect foodborne pathogen are time consuming and laborious. Hence, a variety of methods have been developed for rapid detection of foodborne pathogens as it is required in many food analyses. Rapid detection methods can be categorized into nucleic acid-based, biosensor-based and immunological-based methods. This review emphasizes on the principles and application of recent rapid methods for the detection of foodborne bacterial pathogens. Detection methods included are simple polymerase chain reaction (PCR), multiplex PCR, real-time PCR, nucleic acid sequence-based amplification (NASBA), loop-mediated isothermal amplification (LAMP) and oligonucleotide DNA microarray which classified as nucleic acid-based methods; optical, electrochemical and mass-based biosensors which classified as biosensor-based methods; enzyme-linked immunosorbent assay (ELISA) and lateral flow immunoassay which classified as immunological-based methods. In general, rapid detection methods are generally time-efficient, sensitive, specific and labor-saving. The developments of rapid detection methods are vital in prevention and treatment of foodborne diseases. PMID:25628612

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.

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.

Rapid method to determine 226Ra in steel samples

DOE PAGES

Maxwell, Sherrod L.; Culligan, Brian; Hutchison, Jay B.; ...

2017-09-22

The rapid measurement of 226Ra in steel samples is very important in the event of a radiological emergency. 226Ra (T 1/2 = 1600 y) is a natural radionuclide present in the environment and a highly toxic alpha-emitter. Due to its long life and tendency to concentrate in bones, 226Ra ingestion or inhalation can lead to significant committed dose to individuals. A new method for the determination of 226Ra in steel samples has been developed at the Savannah River Environmental Laboratory. The new method employs a rugged acid digestion method that includes hydrofluoric acid, followed by a single precipitation step tomore » rapidly preconcentrate the radium and remove most of the dissolved steel sample matrix. Radium is then separated using a combination of cation exchange and extraction chromatography, and 226Ra is measured by alpha spectrometry. This approach has a sample preparation time of ~ 8 h for steel samples, has a very high tracer yield (> 88%), and removes interferences effectively. A 133Ba yield tracer is used so that samples can be counted immediately following the separation method, avoiding lengthy ingrowth times that are required in other methods.« less

Rapid method to determine 226Ra in steel samples

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

Maxwell, Sherrod L.; Culligan, Brian; Hutchison, Jay B.

The rapid measurement of 226Ra in steel samples is very important in the event of a radiological emergency. 226Ra (T 1/2 = 1600 y) is a natural radionuclide present in the environment and a highly toxic alpha-emitter. Due to its long life and tendency to concentrate in bones, 226Ra ingestion or inhalation can lead to significant committed dose to individuals. A new method for the determination of 226Ra in steel samples has been developed at the Savannah River Environmental Laboratory. The new method employs a rugged acid digestion method that includes hydrofluoric acid, followed by a single precipitation step tomore » rapidly preconcentrate the radium and remove most of the dissolved steel sample matrix. Radium is then separated using a combination of cation exchange and extraction chromatography, and 226Ra is measured by alpha spectrometry. This approach has a sample preparation time of ~ 8 h for steel samples, has a very high tracer yield (> 88%), and removes interferences effectively. A 133Ba yield tracer is used so that samples can be counted immediately following the separation method, avoiding lengthy ingrowth times that are required in other methods.« less

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.

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.

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.

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.

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.

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.

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.

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.

Thermal Infrared Radiometric Calibration of the Entire Landsat 4, 5, and 7 Archive (1982-2010)

NASA Technical Reports Server (NTRS)

Schott, John R.; Hook, Simon J.; Barsi, Julia A.; Markham, Brian L.; Miller, Jonathan; Padula, Francis P.; Raqueno, Nina G.

2012-01-01

Landsat's continuing record of the thermal state of the earth's surface represents the only long term (1982 to the present) global record with spatial scales appropriate for human scale studies (i.e., tens of meters). Temperature drives many of the physical and biological processes that impact the global and local environment. As our knowledge of, and interest in, the role of temperature on these processes have grown, the value of Landsat data to monitor trends and process has also grown. The value of the Landsat thermal data archive will continue to grow as we develop more effective ways to study the long term processes and trends affecting the planet. However, in order to take proper advantage of the thermal data, we need to be able to convert the data to surface temperatures. A critical step in this process is to have the entire archive completely and consistently calibrated into absolute radiance so that it can be atmospherically compensated to surface leaving radiance and then to surface radiometric temperature. This paper addresses the methods and procedures that have been used to perform the radiometric calibration of the earliest sizable thermal data set in the archive (Landsat 4 data). The completion of this effort along with the updated calibration of the earlier (1985 1999) Landsat 5 data, also reported here, concludes a comprehensive calibration of the Landsat thermal archive of data from 1982 to the present

Investigation of radiometric properties of the LANDSAT-4 multispectral scanner

NASA Technical Reports Server (NTRS)

Malila, W. A. (Principal Investigator); Rice, D. P.

1983-01-01

The radiometric data quality of the LANDSAT 4 multispectral scanner (MSS) was examined using several LANDSAT 4 frames. It was found that LANDSAT 4 MSS produces high-quality data of the caliber experienced with previous LANDSATS. For example, the detector equalization procedure worked well, leaving a residual banding effect of about 0.3 digital counts RMS, close to the theoretical minimum value of quantization error. Nevertheless, artifacts of the data were found, two of which were not experienced in previous MSS data. A low-level coherent noise effect was observed in all bands, with a magnitude of about 0.5 digital counts and a frequency of approximately 28 KHz (representing a wavelength of about 3.6 pixels); a substantial increase in processing complexity would be required to reduce this artifact in the data. Also, a substantial scan-length variation (of up to six pixels) was noted in MSS data when the TM sensor was operating; the LANDSAT 4 correction algorithms being applied routinely by the EROS Data Center to produce a p-type data should remove most of this variation. Between-satellite calibrations were examined in paired LANDSAT 3 and LANDSAT 4 MSS data sets, which were closely matched in acquisition time and place. Radiometric comparisons showed that all bands were highly linear in digital counts, and a well-determined linear transformation between the MSS's was established.

Methods for separation/purification utilizing rapidly cycled thermal swing sorption

DOEpatents

Tonkovich, Anna Lee Y.; Monzyk, Bruce F.; Wang, Yong; VanderWiel, David P.; Perry, Steven T.; Fitzgerald, Sean P.; Simmons, Wayne W.; McDaniel, Jeffrey S.; Weller, Jr., Albert E.

2004-11-09

The present invention provides apparatus and methods for separating fluid components. In preferred embodiments, the apparatus and methods utilize microchannel devices with small distances for heat and mass transfer to achieve rapid cycle times and surprisingly large volumes of fluid components separated in short times using relatively compact hardware.

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

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.

Rapid Detection of Methicillin-Resistant Staphylococcus aureus Isolates by Turanose Fermentation Method

PubMed Central

Raeisi, Javad; Saifi, Mahnaz; Pourshafie, Mohammad Reza; Asadi Karam, Mohammad Reza; Mohajerani, Hamid Reza

2015-01-01

Background: Methicillin-Resistant Staphylococcus aureus (MRSA) is a major pathogen in the hospital and community settings. Rapid methods to diagnose S. aureus infections are sought by many researchers worldwide. The current study aimed to utilize a phenotypic method of turanose fermentation to identify methicillin-susceptible and resistant S. aureus. Objectives: The current study aimed to assay the turanose metabolism at different dilutions as a rapid phenotypic method to identify MRSA isolates. Materials and Methods: A total of 150 Staphylococcus isolates were collected from Tehran health centers. Staphylococcus aureus isolates were identified based on cultural characteristics, biochemical reactions and positive tube coagulase test. Methicillin resistance was determined by the disk diffusion method. The Polymerase Chain Reaction amplification was used to detect the mecA gene in MRSA isolates. All the methicillin-resistant and susceptible isolates were evaluated for turanose metabolism with 1%, 0.7% and 0.5% dilutions using the microplate method. Results: Out of the 150 staphylococcal isolates, 80 were identified as S. aureus. Among which 40 (50%) of the isolates were MRSA. The mecA gene was present in all S. aureus isolates resistant to methicillin. A considerable difference was also observed between susceptible and resistant isolates of S. aureus at a 0.7% dilution of turanose. Conclusions: Since it is highly important to rapidly detect MRSA isolates, especially in nosocomial infections, phenotypic methods may certainly be useful for this purpose. Resistance to methicillin in S. aureus shows a substantially increased ability in turanose metabolism. It is concluded that fermentation of turanose at 0.7% dilution could be a rapid detection method for primary screening of MRSA isolates. PMID:26495105

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.

A method for the rapid detection of urinary tract infections.

PubMed

Olsson, Carl; Kapoor, Deepak; Howard, Glenn

2012-04-01

To determine the reliability of a rapid detection method compared with the reference standard streaked agar plate in diagnosing the presence of urinary tract infection (UTI). De-identified clean catch urine specimens from 980 office visit patients were processed during a 30-day period. Classic 1-μL and 10-μL streaked agar plates were used in parallel with the new CultureStat Rapid UTI Detection System (CSRUDS). Urine results were evaluated using the CSRUDS at 30 and 90 minutes after collection. A comparative analysis of the subsequent plate results versus the CSRUDS results was achieved for 973 of these samples. Positive UTI conditions were accurately identified by both CSRUDS and agar streak plate methods. CSRUDS accurately identified UTI negative conditions with 99.3% reliability at 90 minutes. The negative predictive value of CSRUDS was 99.2% at 30 minutes. Current agar plating for first-round UTI screening has substantial documented problems that can negatively affect an accurate and timely UTI diagnosis. A novel rapid detection system, the CSRUDS provides UTI negative/positive same-day results in ≤ 90 minutes from the start of test. Such rapidly available results will enable more accurate and timely clinical decisions to be made in the urology office, particularly regarding infection status before urologic instrumentation. Copyright © 2012 Elsevier Inc. All rights reserved.

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.

The use of rapid review methods in health technology assessments: 3 case studies.

PubMed

Kaltenthaler, Eva; Cooper, Katy; Pandor, Abdullah; Martyn-St James, Marrissa; Chatters, Robin; Wong, Ruth

2016-08-26

Rapid reviews are of increasing importance within health technology assessment due to time and resource constraints. There are many rapid review methods available although there is little guidance as to the most suitable methods. We present three case studies employing differing methods to suit the evidence base for each review and outline some issues to consider when selecting an appropriate method. Three recently completed systematic review short reports produced for the UK National Institute for Health Research were examined. Different approaches to rapid review methods were used in the three reports which were undertaken to inform the commissioning of services within the NHS and to inform future trial design. We describe the methods used, the reasoning behind the choice of methods and explore the strengths and weaknesses of each method. Rapid review methods were chosen to meet the needs of the review and each review had distinctly different challenges such as heterogeneity in terms of populations, interventions, comparators and outcome measures (PICO) and/or large numbers of relevant trials. All reviews included at least 10 randomised controlled trials (RCTs), each with numerous included outcomes. For the first case study (sexual health interventions), very diverse studies in terms of PICO were included. P-values and summary information only were presented due to substantial heterogeneity between studies and outcomes measured. For the second case study (premature ejaculation treatments), there were over 100 RCTs but also several existing systematic reviews. Data for meta-analyses were extracted directly from existing systematic reviews with new RCT data added where available. For the final case study (cannabis cessation therapies), studies included a wide range of interventions and considerable variation in study populations and outcomes. A brief summary of the key findings for each study was presented and narrative synthesis used to summarise results for each

Euthanasia method for mice in rapid time-course pulmonary pharmacokinetic studies.

PubMed

Schoell, Adam R; Heyde, Bruce R; Weir, Dana E; Chiang, Po-Chang; Hu, Yiding; Tung, David K

2009-09-01

To develop a means of euthanasia to support rapid time-course pharmacokinetic studies in mice, we compared retroorbital and intravenous lateral tail vein injection of ketamine-xylazine with regard to preparation time, utility, tissue distribution, and time to onset of euthanasia. Tissue distribution and time to onset of euthanasia did not differ between administration methods. However, retroorbital injection could be performed more rapidly than intravenous injection and was considered to be a technically simple and superior alternative for mouse euthanasia. Retroorbital ketamine-xylazine, CO(2) gas, and intraperitoneal pentobarbital then were compared as euthanasia agents in a rapid time-point pharmacokinetic study. Retroorbital ketamine-xylazine was the most efficient and consistent of the 3 methods, with an average time to death of approximately 5 s after injection. In addition, euthanasia by retroorbital ketamine-xylazine enabled accurate sample collection at closely spaced time points and satisfied established criteria for acceptable euthanasia technique.

Application of Rapid Prototyping Methods to High-Speed Wind Tunnel Testing

NASA Technical Reports Server (NTRS)

Springer, A. M.

1998-01-01

This study was undertaken in MSFC's 14-Inch Trisonic Wind Tunnel to determine if rapid prototyping methods could be used in the design and manufacturing of high speed wind tunnel models in direct testing applications, and if these methods would reduce model design/fabrication time and cost while providing models of high enough fidelity to provide adequate aerodynamic data, and of sufficient strength to survive the test environment. Rapid prototyping methods utilized to construct wind tunnel models in a wing-body-tail configuration were: fused deposition method using both ABS plastic and PEEK as building materials, stereolithography using the photopolymer SL-5170, selective laser sintering using glass reinforced nylon, and laminated object manufacturing using plastic reinforced with glass and 'paper'. This study revealed good agreement between the SLA model, the metal model with an FDM-ABS nose, an SLA nose, and the metal model for most operating conditions, while the FDM-ABS data diverged at higher loading conditions. Data from the initial SLS model showed poor agreement due to problems in post-processing, resulting in a different configuration. A second SLS model was tested and showed relatively good agreement. It can be concluded that rapid prototyping models show promise in preliminary aerodynamic development studies at subsonic, transonic, and supersonic speeds.

Rapid method for the quantification of hydroquinone concentration: chemiluminescent analysis.

PubMed

Chen, Tung-Sheng; Liou, Show-Yih; Kuo, Wei-Wen; Wu, Hsi-Chin; Jong, Gwo-Ping; Wang, Hsueh-Fang; Shen, Chia-Yao; Padma, V Vijaya; Huang, Chih-Yang; Chang, Yen-Lin

2015-11-01

Topical hydroquinone serves as a skin whitener and is usually available in cosmetics or on prescription based on the hydroquinone concentration. Quantification of hydroquinone content therefore becomes an important issue in topical agents. High-performance liquid chromatography (HPLC) is the commonest method for determining hydroquinone content in topical agents, but this method is time-consuming and uses many solvents that can become an environmental issue. We report a rapid method for quantifying hydroquinone content by chemiluminescent analysis. Hydroquinone induces the production of hydrogen peroxide in the presence of basic compounds. Hydrogen peroxide induced by hydroquinone oxidized light-emitting materials such as lucigenin, resulted in the production of ultra-weak chemiluminescence that was detected by a chemiluminescence analyzer. The intensity of the chemiluminescence was found to be proportional to the hydroquinone concentration. We suggest that the rapid (measurement time, 60 s) and virtually solvent-free (solvent volume, <2 mL) chemiluminescent method described here for quantifying hydroquinone content may be an alternative to HPLC analysis. Copyright © 2015 John Wiley & Sons, Ltd.

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.

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.

Rapid diagnostic methods for influenza virus in clinical specimens - A comparative study

NASA Technical Reports Server (NTRS)

Evans, A. S.; Olson, B.

1982-01-01

A comparison of five rapid viral diagnostic techniques for identifying influenza virus in nasopharyngeal aspirates has been made on patients with influenza-like illnesses. Initial results with immune electron microscopy were positive in only one of 11 specimens from which virus was isolated and further work abandoned. Four other rapid tests were carried out on 39 specimens from which influenza virus had been isolated in tissue culture in 28. Of these 28 specimens yielding virus, 24 (85.7 percent) were positive by an indirect fluorescent antibody test (IFAT) on nasopharyngeal cells, 18 (64.3 percent) by enzyme-linked immunosorbent assay (ELISA), 19 (67.8 percent) by enzyme-linked fluorescent assay (ELFA), and 26 (92.8 percent) by a rapid tissue culture amplification method (TCA) in a continuous Rhesus monkey kidney line (LLC-MK2) with identification of virus by fluorescent antibody. In terms of sensitivity, simplicity, and rapidity, a combination of the IFAT and TCA methods seems to be very useful.

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.

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.

Method for rapidly producing microporous and mesoporous materials

DOEpatents

Coronado, Paul R.; Poco, John F.; Hrubesh, Lawrence W.; Hopper, Robert W.

1997-01-01

An improved, rapid process is provided for making microporous and mesoporous materials, including aerogels and pre-ceramics. A gel or gel precursor is confined in a sealed vessel to prevent structural expansion of the gel during the heating process. This confinement allows the gelation and drying processes to be greatly accelerated, and significantly reduces the time required to produce a dried aerogel compared to conventional methods. Drying may be performed either by subcritical drying with a pressurized fluid to expel the liquid from the gel pores or by supercritical drying. The rates of heating and decompression are significantly higher than for conventional methods.

Rapid method to determine 89Sr/ 90Sr in large concrete samples

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

Maxwell, Sherrod L.; Culligan, Brian; Hutchison, Jay B.

Here, a new rapid method has been developed that provides high quality low-level measurements of 89,90Sr in concrete samples with an MDA (Minimum Detectable Activity) of <1 mBq g -1. The new method is fast, meets new decommissioning regulatory limits and is robust even if refractory particles are present. The method utilizes a rapid fusion to ensure total dissolution of samples and rapid preconcentration and separation of 89,90Sr from 5-10 g concrete samples. When, the 89Sr/ 90Sr ratio is high, Sr can be isolated from up to 5g concrete samples, total 89/90Sr measured, and then 90Sr determined via 90Y separatedmore » after a period of ingrowth. Another approach allows the immediate determination of 90Sr in 10 g concrete aliquots without waiting for 90Y ingrowth, in instances where the shorter lived 89Sr is unlikely to be encountered.« less

Rapid method to determine 89Sr/ 90Sr in large concrete samples

DOE PAGES

Maxwell, Sherrod L.; Culligan, Brian; Hutchison, Jay B.; ...

2016-03-24

Here, a new rapid method has been developed that provides high quality low-level measurements of 89,90Sr in concrete samples with an MDA (Minimum Detectable Activity) of <1 mBq g -1. The new method is fast, meets new decommissioning regulatory limits and is robust even if refractory particles are present. The method utilizes a rapid fusion to ensure total dissolution of samples and rapid preconcentration and separation of 89,90Sr from 5-10 g concrete samples. When, the 89Sr/ 90Sr ratio is high, Sr can be isolated from up to 5g concrete samples, total 89/90Sr measured, and then 90Sr determined via 90Y separatedmore » after a period of ingrowth. Another approach allows the immediate determination of 90Sr in 10 g concrete aliquots without waiting for 90Y ingrowth, in instances where the shorter lived 89Sr is unlikely to be encountered.« less

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).

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).

NIST activities in support of space-based radiometric remote sensing

NASA Astrophysics Data System (ADS)

Rice, Joseph P.; Johnson, B. Carol

2001-06-01

We provide an historical overview of NIST research and development in radiometry for space-based remote sensing. The applications in this field can be generally divided into two areas: environmental and defense. In the environmental remote sensing area, NIST has had programs with agencies such as the National Aeronautical and Space Administration (NASA) and the National Oceanic and Atmospheric Administration (NOAA) to verify and improve traceability of the radiometric calibration of sensors that fly on board Earth-observing satellites. These produce data used in climate models and weather prediction. Over the years, the scope of activities has expanded from existing routine calibration services for artifacts such as lamps, diffusers, and filters, to development and off-site deployment of portable radiometers for radiance- and irradiance-scale intercomparisons. In the defense remote sensing area, NIST has had programs with agencies such as the Department of Defense (DOD) for support of calibration of small, low-level infrared sources in a low infrared background. These are used by the aerospace industry to simulate ballistic missiles in a cold space background. Activities have evolved from calibration of point-source cryogenic blackbodies at NIST to measurement of irradiance in off-site calibration chambers by a portable vacuum/cryogenic radiometer. Both areas of application required measurements on the cutting edge of what was technically feasible, thus compelling NIST to develop a state-of-the-art radiometric measurement infrastructure to meet the needs. This infrastructure has led to improved dissemination of the NIST spectroradiometric quantities.

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.

Euthanasia Method for Mice in Rapid Time-Course Pulmonary Pharmacokinetic Studies

PubMed Central

Schoell, Adam R; Heyde, Bruce R; Weir, Dana E; Chiang, Po-Chang; Hu, Yiding; Tung, David K

2009-01-01

To develop a means of euthanasia to support rapid time-course pharmacokinetic studies in mice, we compared retroorbital and intravenous lateral tail vein injection of ketamine–xylazine with regard to preparation time, utility, tissue distribution, and time to onset of euthanasia. Tissue distribution and time to onset of euthanasia did not differ between administration methods. However, retroorbital injection could be performed more rapidly than intravenous injection and was considered to be a technically simple and superior alternative for mouse euthanasia. Retroorbital ketamine–xylazine, CO2 gas, and intraperitoneal pentobarbital then were compared as euthanasia agents in a rapid time-point pharmacokinetic study. Retroorbital ketamine–xylazine was the most efficient and consistent of the 3 methods, with an average time to death of approximately 5 s after injection. In addition, euthanasia by retroorbital ketamine–xylazine enabled accurate sample collection at closely spaced time points and satisfied established criteria for acceptable euthanasia technique. PMID:19807971

Method for producing rapid pH changes

DOEpatents

Clark, John H.; Campillo, Anthony J.; Shapiro, Stanley L.; Winn, Kenneth R.

1981-01-01

A method of initiating a rapid pH change in a solution by irradiating the solution with an intense flux of electromagnetic radiation of a frequency which produces a substantial pK change to a compound in solution. To optimize the resulting pH change, the compound being irradiated in solution should have an excited state lifetime substantially longer than the time required to establish an excited state acid-base equilibrium in the solution. Desired pH changes can be accomplished in nanoseconds or less by means of picosecond pulses of laser radiation.

Method for producing rapid pH changes

DOEpatents

Clark, J.H.; Campillo, A.J.; Shapiro, S.L.; Winn, K.R.

A method of initiating a rapid pH change in a solution comprises irradiating the solution with an intense flux of electromagnetic radiation of a frequency which produces a substantial pK change to a compound in solution. To optimize the resulting pH change, the compound being irradiated in solution should have an excited state lifetime substantially longer than the time required to establish an excited state acid-base equilibrium in the solution. Desired pH changes can be accomplished in nanoseconds or less by means of picosecond pulses of laser radiation.

A method for measuring total thiaminase activity in fish tissues

USGS Publications Warehouse

Zajicek, James L.; Tillitt, Donald E.; Honeyfield, Dale C.; Brown, Scott B.; Fitzsimons, John D.

2005-01-01

An accurate, quantitative, and rapid method for the measurement of thiaminase activity in fish samples is required to provide sufficient information to characterize the role of dietary thiaminase in the onset of thiamine deficiency in Great Lakes salmonines. A radiometric method that uses 14C-thiamine was optimized for substrate and co-substrate (nicotinic acid) concentrations, incubation time, and sample dilution. Total thiaminase activity was successfully determined in extracts of selected Great Lakes fishes and invertebrates. Samples included whole-body and selected tissues of forage fishes. Positive control material prepared from frozen alewives Alosa pseudoharengus collected in Lake Michigan enhanced the development and application of the method. The method allowed improved discrimination of thiaminolytic activity among forage fish species and their tissues. The temperature dependence of the thiaminase activity observed in crude extracts of Lake Michigan alewives followed a Q10 = 2 relationship for the 1-37??C temperature range, which is consistent with the bacterial-derived thiaminase I protein. ?? Copyright by the American Fisheries Society 2005.

A new rapid method for isolating nucleoli.

PubMed

Li, Zhou Fang; Lam, Yun Wah

2015-01-01

The nucleolus was one of the first subcellular organelles to be isolated from the cell. The advent of modern proteomic techniques has resulted in the identification of thousands of proteins in this organelle, and live cell imaging technology has allowed the study of the dynamics of these proteins. However, the limitations of current nucleolar isolation methods hinder the further exploration of this structure. In particular, these methods require the use of a large number of cells and tedious procedures. In this chapter we describe a new and improved nucleolar isolation method for cultured adherent cells. In this method cells are snap-frozen before direct sonication and centrifugation onto a sucrose cushion. The nucleoli can be obtained within a time as short as 20 min, and the high yield allows the use of less starting material. As a result, this method can capture rapid biochemical changes in nucleoli by freezing the cells at a precise time, hence faithfully reflecting the protein composition of nucleoli at the specified time point. This protocol will be useful for proteomic studies of dynamic events in the nucleolus and for better understanding of the biology of mammalian cells.

Performance and Results from a Space Borne, Uncooled Microbolometer Array Spectral Radiometric Imager

NASA Technical Reports Server (NTRS)

Spinhirne, James M; Scott, V. Stan; Lancaster, Redgie S.; Manizade, Kathrine; Palm, Steven P.

2000-01-01

The Infrared Spectral Imaging Radiometer experiment was flown on a space shuttle mission as a shuttle hitchhiker experiment in August of 1997. The goals of the experiment were to test uncooled array detectors for infrared spectral imaging from space and to apply for the first time retrieval from space of brightness temperatures of cloud, land and sea along with direct laser measurements of cloud top height. The instrument operates in 3 narrow and one broad spectral band, all between 7 and 13 microns in either stare or time-delay and integration mode. The nominal spatial resolution was 1/4 kilometer. Using onboard calibrations along with periodic views of deep space, radiometric calibration of imagery was carried out and performance analyzed. The noise equivalent temperature difference and absolute accuracy reported here varied with operating mode, spectral band and scene temperature but were within requirements. This paper provides a description of the instrument, its operating modes, the method of brightness temperature retrieval, the method of spectral registration and results from the flight.

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.

Preparing silica aerogel monoliths via a rapid supercritical extraction method.

PubMed

Carroll, Mary K; Anderson, Ann M; Gorka, Caroline A

2014-02-28

A procedure for the fabrication of monolithic silica aerogels in eight hours or less via a rapid supercritical extraction process is described. The procedure requires 15-20 min of preparation time, during which a liquid precursor mixture is prepared and poured into wells of a metal mold that is placed between the platens of a hydraulic hot press, followed by several hours of processing within the hot press. The precursor solution consists of a 1.0:12.0:3.6:3.5 x 10(-3) molar ratio of tetramethylorthosilicate (TMOS):methanol:water:ammonia. In each well of the mold, a porous silica sol-gel matrix forms. As the temperature of the mold and its contents is increased, the pressure within the mold rises. After the temperature/pressure conditions surpass the supercritical point for the solvent within the pores of the matrix (in this case, a methanol/water mixture), the supercritical fluid is released, and monolithic aerogel remains within the wells of the mold. With the mold used in this procedure, cylindrical monoliths of 2.2 cm diameter and 1.9 cm height are produced. Aerogels formed by this rapid method have comparable properties (low bulk and skeletal density, high surface area, mesoporous morphology) to those prepared by other methods that involve either additional reaction steps or solvent extractions (lengthier processes that generate more chemical waste).The rapid supercritical extraction method can also be applied to the fabrication of aerogels based on other precursor recipes.

Preparing Silica Aerogel Monoliths via a Rapid Supercritical Extraction Method

PubMed Central

Gorka, Caroline A.

2014-01-01

A procedure for the fabrication of monolithic silica aerogels in eight hours or less via a rapid supercritical extraction process is described. The procedure requires 15-20 min of preparation time, during which a liquid precursor mixture is prepared and poured into wells of a metal mold that is placed between the platens of a hydraulic hot press, followed by several hours of processing within the hot press. The precursor solution consists of a 1.0:12.0:3.6:3.5 x 10-3 molar ratio of tetramethylorthosilicate (TMOS):methanol:water:ammonia. In each well of the mold, a porous silica sol-gel matrix forms. As the temperature of the mold and its contents is increased, the pressure within the mold rises. After the temperature/pressure conditions surpass the supercritical point for the solvent within the pores of the matrix (in this case, a methanol/water mixture), the supercritical fluid is released, and monolithic aerogel remains within the wells of the mold. With the mold used in this procedure, cylindrical monoliths of 2.2 cm diameter and 1.9 cm height are produced. Aerogels formed by this rapid method have comparable properties (low bulk and skeletal density, high surface area, mesoporous morphology) to those prepared by other methods that involve either additional reaction steps or solvent extractions (lengthier processes that generate more chemical waste).The rapid supercritical extraction method can also be applied to the fabrication of aerogels based on other precursor recipes. PMID:24637334

The radiometric performances of the Planetary Fourier Spectrometer for Mars exploration

NASA Astrophysics Data System (ADS)

Palomba, E.; Colangeli, L.; Formisano, V.; Piccioni, G.; Cafaro, N.; Moroz, V.

1999-04-01

The Planetary Fourier Spectrometer (PFS) is a Fourier transform interferometer, operating in the range 1.2-45 μm. The instrument, previously included in the payload of the failed mission Mars ‧96, is proposed for the future space mission Mars Express, under study by ESA. The present paper is aimed at presenting the radiometric performances of PFS. The two channels (LW and SW) forming PFS were analysed and characterised in terms of sensitivity and noise equivalent brightness. To cover the wide spectral range of PFS, different blackbodies were used for calibration. The built-in blackbodies, needed for the in-flight calibrations, were also characterised. The results show that the LW channel is comparable with IRIS Mariner 9 in terms of noise equivalent brightness. The SW channel performances, while satisfactorily, could be improved by lowering the sensor operative temperature. A simple model of the Mars radiance is used in order to calculate the signal-to-noise ratio on the spectra in typical observation conditions. The computed signal-to-noise ratio for the LW channel varies between 430 and 40, while for the SW channel it ranges from 150 to 30. The radiometric analyses confirm that PFS performances are compliant with the design requirements of the instrument. PFS is fully validated for future remote exploration of the atmosphere and the surface of Mars.

A validation procedure for a LADAR system radiometric simulation model

NASA Astrophysics Data System (ADS)

Leishman, Brad; Budge, Scott; Pack, Robert

2007-04-01

The USU LadarSIM software package is a ladar system engineering tool that has recently been enhanced to include the modeling of the radiometry of Ladar beam footprints. This paper will discuss our validation of the radiometric model and present a practical approach to future validation work. In order to validate complicated and interrelated factors affecting radiometry, a systematic approach had to be developed. Data for known parameters were first gathered then unknown parameters of the system were determined from simulation test scenarios. This was done in a way to isolate as many unknown variables as possible, then build on the previously obtained results. First, the appropriate voltage threshold levels of the discrimination electronics were set by analyzing the number of false alarms seen in actual data sets. With this threshold set, the system noise was then adjusted to achieve the appropriate number of dropouts. Once a suitable noise level was found, the range errors of the simulated and actual data sets were compared and studied. Predicted errors in range measurements were analyzed using two methods: first by examining the range error of a surface with known reflectivity and second by examining the range errors for specific detectors with known responsivities. This provided insight into the discrimination method and receiver electronics used in the actual system.

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.

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.

Method for rapidly producing microporous and mesoporous materials

DOEpatents

Coronado, P.R.; Poco, J.F.; Hrubesh, L.W.; Hopper, R.W.

1997-11-11

An improved, rapid process is provided for making microporous and mesoporous materials, including aerogels and pre-ceramics. A gel or gel precursor is confined in a sealed vessel to prevent structural expansion of the gel during the heating process. This confinement allows the gelation and drying processes to be greatly accelerated, and significantly reduces the time required to produce a dried aerogel compared to conventional methods. Drying may be performed either by subcritical drying with a pressurized fluid to expel the liquid from the gel pores or by supercritical drying. The rates of heating and decompression are significantly higher than for conventional methods. 3 figs.

USING AN INTENSIVE ASSESSMENT METHOD TO CALIBRATE A RAPID WETLAND ASSESSMENT METHOD: AN EXAMPLE FROM NANTICOKE BASIN, DELAWARE AND MARYLAND, USA

EPA Science Inventory

The development of rapid assessment methods has become a priority for many organizations that want to report on the condition of wetlands at larger scales requiring many sampling sites. To have faith in these rapid methods, however, requires that they be verified with more compr...

In-flight radiometric calibration of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)

NASA Technical Reports Server (NTRS)

Conel, James E.; Green, Robert O.; Alley, Ronald E.; Bruegge, Carol J.; Carrere, Veronique; Margolis, Jack S.; Vane, Gregg; Chrien, Thomas G.; Slater, Philip N.; Biggard, Stuart F.

1988-01-01

A reflectance-based method was used to provide an analysis of the in-flight radiometric performance of AVIRIS. Field spectral reflectance measurements of the surface and extinction measurements of the atmosphere using solar radiation were used as input to atmospheric radiative transfer calculations. Five separate codes were used in the analysis. Four include multiple scattering, and the computed radiances from these for flight conditions were in good agreement. Code-generated radiances were compared with AVIRIS-predicted radiances based on two laboratory calibrations (pre- and post-season of flight) for a uniform highly reflecting natural dry lake target. For one spectrometer (C), the pre- and post-season calibration factors were found to give identical results, and to be in agreement with the atmospheric models that include multiple scattering. This positive result validates the field and laboratory calibration technique. Results for the other spectrometers (A, B and D) were widely at variance with the models no matter which calibration factors were used. Potential causes of these discrepancies are discussed.

Fuji apple storage time rapid determination method using Vis/NIR spectroscopy.

PubMed

Liu, Fuqi; Tang, Xuxiang

2015-01-01

Fuji apple storage time rapid determination method using visible/near-infrared (Vis/NIR) spectroscopy was studied in this paper. Vis/NIR diffuse reflection spectroscopy responses to samples were measured for 6 days. Spectroscopy data were processed by stochastic resonance (SR). Principal component analysis (PCA) was utilized to analyze original spectroscopy data and SNR eigen value. Results demonstrated that PCA could not totally discriminate Fuji apples using original spectroscopy data. Signal-to-noise ratio (SNR) spectrum clearly classified all apple samples. PCA using SNR spectrum successfully discriminated apple samples. Therefore, Vis/NIR spectroscopy was effective for Fuji apple storage time rapid discrimination. The proposed method is also promising in condition safety control and management for food and environmental laboratories.

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.

Rapid identification of salmonella serotypes with stereo and hyperspectral microscope imaging Methods

USDA-ARS?s Scientific Manuscript database

The hyperspectral microscope imaging (HMI) method can reduce detection time within 8 hours including incubation process. The early and rapid detection with this method in conjunction with the high throughput capabilities makes HMI method a prime candidate for implementation for the food industry. Th...

Rapid Identification of Salmonella Serotypes with Stereo and Hyperspectral Microscope Imaging Methods

USDA-ARS?s Scientific Manuscript database

The hyperspectral microscope imaging (HMI) method can reduce detection time within 8 hours including incubation process. The early and rapid detection with this method in conjunction with the high throughput capabilities makes HMI method a prime candidate for implementation for the food industry. Th...

Evaluation of PDA Technical Report No 33. Statistical Testing Recommendations for a Rapid Microbiological Method Case Study.

PubMed

Murphy, Thomas; Schwedock, Julie; Nguyen, Kham; Mills, Anna; Jones, David

2015-01-01

New recommendations for the validation of rapid microbiological methods have been included in the revised Technical Report 33 release from the PDA. The changes include a more comprehensive review of the statistical methods to be used to analyze data obtained during validation. This case study applies those statistical methods to accuracy, precision, ruggedness, and equivalence data obtained using a rapid microbiological methods system being evaluated for water bioburden testing. Results presented demonstrate that the statistical methods described in the PDA Technical Report 33 chapter can all be successfully applied to the rapid microbiological method data sets and gave the same interpretation for equivalence to the standard method. The rapid microbiological method was in general able to pass the requirements of PDA Technical Report 33, though the study shows that there can be occasional outlying results and that caution should be used when applying statistical methods to low average colony-forming unit values. Prior to use in a quality-controlled environment, any new method or technology has to be shown to work as designed by the manufacturer for the purpose required. For new rapid microbiological methods that detect and enumerate contaminating microorganisms, additional recommendations have been provided in the revised PDA Technical Report No. 33. The changes include a more comprehensive review of the statistical methods to be used to analyze data obtained during validation. This paper applies those statistical methods to analyze accuracy, precision, ruggedness, and equivalence data obtained using a rapid microbiological method system being validated for water bioburden testing. The case study demonstrates that the statistical methods described in the PDA Technical Report No. 33 chapter can be successfully applied to rapid microbiological method data sets and give the same comparability results for similarity or difference as the standard method. © PDA, Inc

[Accuracy of three methods for the rapid diagnosis of oral candidiasis].

PubMed

Lyu, X; Zhao, C; Yan, Z M; Hua, H

2016-10-09

Objective: To explore a simple, rapid and efficient method for the diagnosis of oral candidiasis in clinical practice. Methods: Totally 124 consecutive patients with suspected oral candidiasis were enrolled from Department of Oral Medicine, Peking University School and Hospital of Stomatology, Beijing, China. Exfoliated cells of oral mucosa and saliva or concentrated oral rinse) obtained from all participants were tested by three rapid smear methods(10% KOH smear, gram-stained smear, Congo red stained smear). The diagnostic efficacy(sensitivity, specificity, Youden's index, likelihood ratio, consistency, predictive value and area under curve(AUC) of each of the above mentioned three methods was assessed by comparing the results with the gold standard(combination of clinical diagnosis, laboratory diagnosis and expert opinion). Results: Gram-stained smear of saliva(or concentrated oral rinse) demonstrated highest sensitivity(82.3%). Test of 10%KOH smear of exfoliated cells showed highest specificity(93.5%). Congo red stained smear of saliva(or concentrated oral rinse) displayed highest diagnostic efficacy(79.0% sensitivity, 80.6% specificity, 0.60 Youden's index, 4.08 positive likelihood ratio, 0.26 negative likelihood ratio, 80% consistency, 80.3% positive predictive value, 79.4% negative predictive value and 0.80 AUC). Conclusions: Test of Congo red stained smear of saliva(or concentrated oral rinse) could be used as a point-of-care tool for the rapid diagnosis of oral candidiasis in clinical practice. Trial registration: Chinese Clinical Trial Registry, ChiCTR-DDD-16008118.

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.

Rapid determination of tannins in tanning baths by adaptation of BSA method.

PubMed

Molinari, R; Buonomenna, M G; Cassano, A; Drioli, E

2001-01-01

A rapid and reproducible method for the determination of tannins in vegetable tanning baths is proposed as a modification of the BSA method for grain tannins existing in literature. The protein BSA was used instead of leather powder employed in the Filter Method, which is adopted in Italy and various others countries of Central Europe. In this rapid method the tannin contents is determined by means a spectrophotometric reading and not by means a gravimetric analysis of the Filter Method. The BSA method, which belongs to mixed methods (which use both precipitation and complexation of tannins), consists of selective precipitation of tannin from a solution containing also non tannins by BSA, the dissolution of precipitate and the quantification of free tannin amount by its complexation with Fe(III) in hydrochloric solutions. The absorbance values, read at 522 nm, have been expressed in terms of tannic acid concentration by using a calibration curve made with standard solutions of tannic acid; these have been correlated with the results obtained by using the Filter Method.

Fuji apple storage time rapid determination method using Vis/NIR spectroscopy

PubMed Central

Liu, Fuqi; Tang, Xuxiang

2015-01-01

Fuji apple storage time rapid determination method using visible/near-infrared (Vis/NIR) spectroscopy was studied in this paper. Vis/NIR diffuse reflection spectroscopy responses to samples were measured for 6 days. Spectroscopy data were processed by stochastic resonance (SR). Principal component analysis (PCA) was utilized to analyze original spectroscopy data and SNR eigen value. Results demonstrated that PCA could not totally discriminate Fuji apples using original spectroscopy data. Signal-to-noise ratio (SNR) spectrum clearly classified all apple samples. PCA using SNR spectrum successfully discriminated apple samples. Therefore, Vis/NIR spectroscopy was effective for Fuji apple storage time rapid discrimination. The proposed method is also promising in condition safety control and management for food and environmental laboratories. PMID:25874818

Landsat-7 ETM+ radiometric stability and absolute calibration

USGS Publications Warehouse

Markham, B.L.; Barker, J.L.; Barsi, J.A.; Kaita, E.; Thome, K.J.; Helder, D.L.; Palluconi, Frank Don; Schott, J.R.; Scaramuzza, Pat; ,

2002-01-01

Launched in April 1999, the Landsat-7 ETM+ instrument is in its fourth year of operation. The quality of the acquired calibrated imagery continues to be high, especially with respect to its three most important radiometric performance parameters: reflective band instrument stability to better than ??1%, reflective band absolute calibration to better than ??5%, and thermal band absolute calibration to better than ??0.6 K. The ETM+ instrument has been the most stable of any of the Landsat instruments, in both the reflective and thermal channels. To date, the best on-board calibration source for the reflective bands has been the Full Aperture Solar Calibrator, which has indicated changes of at most -1.8% to -2.0% (95% C.I.) change per year in the ETM+ gain (band 4). However, this change is believed to be caused by changes in the solar diffuser panel, as opposed to a change in the instrument's gain. This belief is based partially on ground observations, which bound the changes in gain in band 4 at -0.7% to +1.5%. Also, ETM+ stability is indicated by the monitoring of desert targets. These image-based results for four Saharan and Arabian sites, for a collection of 35 scenes over the three years since launch, bound the gain change at -0.7% to +0.5% in band 4. Thermal calibration from ground observations revealed an offset error of +0.31 W/m 2 sr um soon after launch. This offset was corrected within the U. S. ground processing system at EROS Data Center on 21-Dec-00, and since then, the band 6 on-board calibration has indicated changes of at most +0.02% to +0.04% (95% C.I.) per year. The latest ground observations have detected no remaining offset error with an RMS error of ??0.6 K. The stability and absolute calibration of the Landsat-7 ETM+ sensor make it an ideal candidate to be used as a reference source for radiometric cross-calibrating to other land remote sensing satellite systems.

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.

Gravity, magnetic, and radiometric data for Newberry Volcano, Oregon, and vicinity

USGS Publications Warehouse

Wynn, Jeff

2014-01-01

Newberry Volcano in central Oregon is a 3,100-square-kilometer (1,200-square-mile) shield-shaped composite volcano, occupying a location east of the main north-south trend of the High Cascades volcanoes and forming a transition between the High Lava Plains subprovince of the Basin and Range Province to the east and the Cascade Range to the west. Magnetic, gravity, and radiometric data have been gathered and assessed for the region around the volcano. These data have widely varying quality and resolution, even within a given dataset, and these limitations are evaluated and described in this release. Publicly available gravity data in general are too sparse to permit detailed modeling except along a few roads with high-density coverage. Likewise, magnetic data are also unsuitable for all but very local modeling, primarily because available data consist of a patchwork of datasets with widely varying line-spacing. Gravity data show only the broadest correlation with mapped geology, whereas magnetic data show moderate correlation with features only in the vicinity of Newberry Caldera. At large scales, magnetic data correlate poorly with both geologic mapping and gravity data. These poor correlations are largely due to the different sensing depths of the two potential fields methods, which respond to physical properties deeper than the surficial geology. Magnetic data derive from rocks no deeper than the Curie-point isotherm depth (10 to 15 kilometers, km, maximum), whereas gravity data reflect density-contrasts to 100 to 150 km depths. Radiometric data from the National Uranium Resource Evaluation (NURE) surveys of the 1980s have perhaps the coarsest line-spacing of all (as much as 10 km between lines) and are extremely “noisy” for several reasons inherent to this kind of data. Despite its shallow-sensing character, only a few larger anomalies in the NURE data correlate well with geologic mapping. The purpose of this data series release is to collect and place the

An international survey and modified Delphi approach revealed numerous rapid review methods.

PubMed

Tricco, Andrea C; Zarin, Wasifa; Antony, Jesmin; Hutton, Brian; Moher, David; Sherifali, Diana; Straus, Sharon E

2016-02-01

To solicit experiences with and perceptions of rapid reviews from stakeholders, including researchers, policy makers, industry, journal editors, and health care providers. An international survey of rapid review producers and modified Delphi. Forty rapid review producers responded on our survey (63% response rate). Eighty-eight rapid reviews with 31 different names were reported. Rapid review commissioning organizations were predominantly government (78%) and health care (58%) organizations. Several rapid review approaches were identified, including updating the literature search of previous reviews (92%); limiting the search strategy by date of publication (88%); and having only one reviewer screen (85%), abstract data (84%), and assess the quality of studies (86%). The modified Delphi included input from 113 stakeholders on the rapid review approaches from the survey. Approach 1 (search limited by date and language; study selection by one reviewer only, and data abstraction and quality appraisal conducted by one reviewer and one verifier) was ranked the most feasible (72%, 81/113 responses), with the lowest perceived risk of bias (12%, 12/103); it also ranked second in timeliness (37%, 38/102) and fifth in comprehensiveness (5%, 5/100). Rapid reviews have many names and approaches, and some methods might be more desirable than others. Copyright © 2016 Elsevier Inc. All rights reserved.

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

Aerial radiometric and magnetic reconnaissance survey of the Eagle--Dillingham area, Alaska, Mt. Hayes Quadrangle

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

Not Available

1978-06-01

The results of a high-sensitivity aerial gamma-ray spectrometer and magnetometer survey of the Mt. Hayes Quadrangle, Alaska, are presented. Instrumentation and methods are described in Volume 1 of this final report. Statistical and geological analysis of the radiometric data revealed two uranium anomalies worthy of field checking as possible prospects. One is located near Mesozoic granite, which is believed to have the best potential for future economic uranium deposits. Another uranium anomaly is associated with Paleozoic-Precambrian rocks and may be caused by augen gneiss or possibly granitic intrusives. Two weakly uraniferous provinces merit study: one in the northwest, which maymore » be related to the Tertiary-Cretaceous coal-bearing unit, and a second in the northeast, which may be related to Mesozoic granites.« less

Method for rapid estimation of scour at highway bridges based on limited site data

USGS Publications Warehouse

Holnbeck, S.R.; Parrett, Charles

1997-01-01

Limited site data were used to develop a method for rapid estimation of scour at highway bridges. The estimates can be obtained in a matter of hours rather than several days as required by more-detailed methods. Such a method is important because scour assessments are needed to identify scour-critical bridges throughout the United States. Using detailed scour-analysis methods and scour-prediction equations recommended by the Federal Highway Administration, the U.S. Geological Survey, in cooperation with the Montana Department of Transportation, obtained contraction, pier, and abutment scour-depth data for sites from 10 States.The data were used to develop relations between scour depth and hydraulic variables that can be rapidly measured in the field. Relations between scour depth and hydraulic variables, in the form of envelope curves, were based on simpler forms of detailed scour-prediction equations. To apply the rapid-estimation method, a 100-year recurrence interval peak discharge is determined, and bridge- length data are used in the field with graphs relating unit discharge to velocity and velocity to bridge backwater as a basis for estimating flow depths and other hydraulic variables that can then be applied using the envelope curves. The method was tested in the field. Results showed good agreement among individuals involved and with results from more-detailed methods. Although useful for identifying potentially scour-critical bridges, themethod does not replace more-detailed methods used for design purposes. Use of the rapid- estimation method should be limited to individuals having experience in bridge scour, hydraulics, and flood hydrology, and some training in use of the method.

RAPID SEPARATION METHOD FOR EMERGENCY WATER AND URINE SAMPLES

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

Maxwell, S.; Culligan, B.

2008-08-27

The Savannah River Site Environmental Bioassay Lab participated in the 2008 NRIP Emergency Response program administered by the National Institute for Standards and Technology (NIST) in May, 2008. A new rapid column separation method was used for analysis of actinides and {sup 90}Sr the NRIP 2008 emergency water and urine samples. Significant method improvements were applied to reduce analytical times. As a result, much faster analysis times were achieved, less than 3 hours for determination of {sup 90}Sr and 3-4 hours for actinides. This represents a 25%-33% improvement in analysis times from NRIP 2007 and a {approx}100% improvement compared tomore » NRIP 2006 report times. Column flow rates were increased by a factor of two, with no significant adverse impact on the method performance. Larger sample aliquots, shorter count times, faster cerium fluoride microprecipitation and streamlined calcium phosphate precipitation were also employed. Based on initial feedback from NIST, the SRS Environmental Bioassay Lab had the most rapid analysis times for actinides and {sup 90}Sr analyses for NRIP 2008 emergency urine samples. High levels of potential matrix interferences may be present in emergency samples and rugged methods are essential. Extremely high levels of {sup 210}Po were found to have an adverse effect on the uranium results for the NRIP-08 urine samples, while uranium results for NRIP-08 water samples were not affected. This problem, which was not observed for NRIP-06 or NRIP-07 urine samples, was resolved by using an enhanced {sup 210}Po removal step, which will be described.« less

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.

Radiometric sensitivity comparisons of multispectral imaging systems

NASA Technical Reports Server (NTRS)

Lu, Nadine C.; Slater, Philip N.

1989-01-01

Multispectral imaging systems provide much of the basic data used by the land and ocean civilian remote-sensing community. There are numerous multispectral imaging systems which have been and are being developed. A common way to compare the radiometric performance of these systems is to examine their noise-equivalent change in reflectance, NE Delta-rho. The NE Delta-rho of a system is the reflectance difference that is equal to the noise in the recorded signal. A comparison is made of the noise equivalent change in reflectance of seven different multispectral imaging systems (AVHRR, AVIRIS, ETM, HIRIS, MODIS-N, SPOT-1, HRV, and TM) for a set of three atmospheric conditions (continental aerosol with 23-km visibility, continental aerosol with 5-km visibility, and a Rayleigh atmosphere), five values of ground reflectance (0.01, 0.10, 0.25, 0.50, and 1.00), a nadir viewing angle, and a solar zenith angle of 45 deg.

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

Rapid assessment method for prevalence and intensity of Loa loa infection.

PubMed Central

Takougang, Innocent; Meremikwu, Martin; Wandji, Samuel; Yenshu, Emmanuel V.; Aripko, Ben; Lamlenn, Samson B.; Eka, Braide L.; Enyong, Peter; Meli, Jean; Kale, Oladele; Remme, Jan H.

2002-01-01

OBJECTIVE: To assess the validity of observations on eye worm and Calabar swellings for the rapid assessment of the prevalence and intensity of loiasis at the community level. METHOD: A total of 12895 individuals over the age of 15 years living in 102 communities in Cameroon and Nigeria took part in the study. A standardized questionnaire was administered to participants from whom finger-prick blood samples were collected and examined for Loa loa microfilariae. Rapid assessments of the prevalence and intensity of loiasis were made on the basis of a history of eye worm or Calabar swellings. FINDINGS: There was a strong correlation between the indices of the rapid assessment procedures and the parasitological indices of L. loa endemicity. The rapid assessment indices were effective in diagnosing high-risk communities (sensitivity 94-100%; specificity 66-92%). The highest sensitivity (100%) and specificity (92%) were obtained with a rapid assessment procedure based on a history of eye worm lasting 1-7 days together with confirmation by the guided recognition of a photograph of adult L. loa in the eye. CONCLUSION: Rapid assessment of the prevalence and intensity of loiasis at the community level can be achieved using a procedure based on the history of eye worm lasting 1-7 days together with confirmation by the guided recognition of a photograph of an adult L. loa in the eye. PMID:12481206

A parameter control method in reinforcement learning to rapidly follow unexpected environmental changes.

PubMed

Murakoshi, Kazushi; Mizuno, Junya

2004-11-01

In order to rapidly follow unexpected environmental changes, we propose a parameter control method in reinforcement learning that changes each of learning parameters in appropriate directions. We determine each appropriate direction on the basis of relationships between behaviors and neuromodulators by considering an emergency as a key word. Computer experiments show that the agents using our proposed method could rapidly respond to unexpected environmental changes, not depending on either two reinforcement learning algorithms (Q-learning and actor-critic (AC) architecture) or two learning problems (discontinuous and continuous state-action problems).

Use of a novel radiometric method to assess the inhibitory effect of donepezil on acetylcholinesterase activity in minimally diluted tissue samples

PubMed Central

Kikuchi, Tatsuya; Okamura, Toshimitsu; Arai, Takuya; Obata, Takayuki; Fukushi, Kiyoshi; Irie, Toshiaki; Shiraishi, Tetsuya

2010-01-01

Background and purpose: Cholinesterase inhibitors have been widely used for the treatment of patients with dementia. Monitoring of the cholinesterase activity in the blood is used as an indicator of the effect of the cholinesterase inhibitors in the brain. The selective measurement of cholinesterase with low tissue dilution is preferred for accurate monitoring; however, the methods have not been established. Here, we investigated the effect of tissue dilution on the action of cholinesterase inhibitors using a novel radiometric method with selective substrates, N-[14C]methylpiperidin-4-yl acetate ([14C]MP4A) and (R)-N-[14C]methylpiperidin-3-yl butyrate ([14C]MP3B_R), for AChE and butyrylcholinesterase (BChE) respectively. Experimental approach: We investigated the kinetics of hydrolysis of [14C]-MP4A and [14C]-MP3B_R by cholinesterases, and evaluated the selectivity of [14C]MP4A and [14C]MP3B_R for human AChE and BChE, respectively, compared with traditional substrates. Then, IC50 values of cholinesterase inhibitors in minimally diluted and highly diluted tissues were measured with [14C]MP4A and [14C]MP3B_R. Key results: AChE and BChE activities were selectively measured as the first-order hydrolysis rates of [14C]-MP4A and [14C]MP3B_R respectively. The AChE selectivity of [14C]MP4A was an order of magnitude higher than traditional substrates used for the AChE assay. The IC50 values of specific AChE and BChE inhibitors, donepezil and ethopropazine, in 1.2-fold diluted human whole blood were much higher than those in 120-fold diluted blood. In addition, the IC50 values of donepezil in monkey brain were dramatically decreased as the tissue was diluted. Conclusions and implications: This method would effectively monitor the activity of cholinesterase inhibitors used for therapeutics, pesticides and chemical warfare agents. PMID:20401964

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.

Non-supervised method for early forest fire detection and rapid mapping

NASA Astrophysics Data System (ADS)

Artés, Tomás; Boca, Roberto; Liberta, Giorgio; San-Miguel, Jesús

2017-09-01

Natural hazards are a challenge for the society. Scientific community efforts have been severely increased assessing tasks about prevention and damage mitigation. The most important points to minimize natural hazard damages are monitoring and prevention. This work focuses particularly on forest fires. This phenomenon depends on small-scale factors and fire behavior is strongly related to the local weather. Forest fire spread forecast is a complex task because of the scale of the phenomena, the input data uncertainty and time constraints in forest fire monitoring. Forest fire simulators have been improved, including some calibration techniques avoiding data uncertainty and taking into account complex factors as the atmosphere. Such techniques increase dramatically the computational cost in a context where the available time to provide a forecast is a hard constraint. Furthermore, an early mapping of the fire becomes crucial to assess it. In this work, a non-supervised method for forest fire early detection and mapping is proposed. As main sources, the method uses daily thermal anomalies from MODIS and VIIRS combined with land cover map to identify and monitor forest fires with very few resources. This method relies on a clustering technique (DBSCAN algorithm) and on filtering thermal anomalies to detect the forest fires. In addition, a concave hull (alpha shape algorithm) is applied to obtain rapid mapping of the fire area (very coarse accuracy mapping). Therefore, the method leads to a potential use for high-resolution forest fire rapid mapping based on satellite imagery using the extent of each early fire detection. It shows the way to an automatic rapid mapping of the fire at high resolution processing as few data as possible.

Aerial radiometric and magnetic reconnaissance survey of Baltimore, Washington, and Richmond Quadrangles: Washington Quadrangle

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

Not Available

1978-09-01

The results of a high-sensitivity aerial gamma-ray spectrometer and magnetometer survey of the Washington Quadrangle, Maryland and Virginia, are presentd. Instrumentation and methods are described in Volume 1 of this final report. Statistical and geological analysis of the radiometric data revealed six uranium anomalies worthy of field checking as possible prospects. Four (1, 2, 7, and 8) are located over sediments that may have long-range future potential for low-grade sedimentary uranium deposits. In particular, anomalies 1 and 8 are related to a unit (Triassic New Oxford Formation) known to contain uranium occurrences in Pennsylvania. One anomaly (3) may be associatedmore » with vein-type mineralization in augen gneiss, and one (12) may be caused by vein-type or hydrothermal uranium associated with a north-south striking fault at the boundary between the Appalachian Highlands and the Coastal Plain physiographic provinces.« less

Estimation of the cloud transmittance from radiometric measurements at the ground level

NASA Astrophysics Data System (ADS)

Costa, Dario; Mares, Oana

2014-11-01

The extinction of solar radiation due to the clouds is more significant than due to any other atmospheric constituent, but it is always difficult to be modeled because of the random distribution of clouds on the sky. Moreover, the transmittance of a layer of clouds is in a very complex relation with their type and depth. A method for estimating cloud transmittance was proposed in Paulescu et al. (Energ. Convers. Manage, 75 690-697, 2014). The approach is based on the hypothesis that the structure of the cloud covering the sun at a time moment does not change significantly in a short time interval (several minutes). Thus, the cloud transmittance can be calculated as the estimated coefficient of a simple linear regression for the computed versus measured solar irradiance in a time interval Δt. The aim of this paper is to optimize the length of the time interval Δt. Radiometric data measured on the Solar Platform of the West University of Timisoara during 2010 at a frequency of 1/15 seconds are used in this study.

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.

Rapid surface enhanced Raman scattering detection method for chloramphenicol residues

NASA Astrophysics Data System (ADS)

Ji, Wei; Yao, Weirong

2015-06-01

Chloramphenicol (CAP) is a widely used amide alcohol antibiotics, which has been banned from using in food producing animals in many countries. In this study, surface enhanced Raman scattering (SERS) coupled with gold colloidal nanoparticles was used for the rapid analysis of CAP. Density functional theory (DFT) calculations were conducted with Gaussian 03 at the B3LYP level using the 3-21G(d) and 6-31G(d) basis sets to analyze the assignment of vibrations. Affirmatively, the theoretical Raman spectrum of CAP was in complete agreement with the experimental spectrum. They both exhibited three strong peaks characteristic of CAP at 1104 cm-1, 1344 cm-1, 1596 cm-1, which were used for rapid qualitative analysis of CAP residues in food samples. The use of SERS as a method for the measurements of CAP was explored by comparing use of different solvents, gold colloidal nanoparticles concentration and absorption time. The method of the detection limit was determined as 0.1 μg/mL using optimum conditions. The Raman peak at 1344 cm-1 was used as the index for quantitative analysis of CAP in food samples, with a linear correlation of R2 = 0.9802. Quantitative analysis of CAP residues in foods revealed that the SERS technique with gold colloidal nanoparticles was sensitive and of a good stability and linear correlation, and suited for rapid analysis of CAP residue in a variety of food samples.

A rapid method for determining salinomycin and monensin sensitivity in Eimeria tenella

USDA-ARS?s Scientific Manuscript database

Standard methods of determining the ionophore sensitivity of Eimeria rely on infecting chickens with an isolate or a mixture of Eimeria spp. oocysts in the presence of different anti-coccidial drugs. The purpose of this study was to develop a rapid in vitro method for assessing salinomycin and mone...

Rapid method to extract DNA from Cryptococcus neoformans.

PubMed Central

Varma, A; Kwon-Chung, K J

1991-01-01

A rapid and easy method for the extraction of total cellular DNA from Cryptococcus neoformans is described. This procedure modifies and considerably simplifies previously reported methods. Numerous steps were either eliminated or replaced, including preincubations with cell wall permeability agents such as beta-mercaptoethanol and dithiothreitol. The commercially available enzyme preparation Novozyme 234 was found to contain a potent concentration of DNases which actively degrade DNA. Degradation and loss of DNA was prevented by maintaining a high concentration of EDTA in the lysing solution. This procedure resulted in high yields (150 to 200 micrograms of DNA from 100 ml of culture) of good-quality (undegraded), high-molecular-weight DNA which was readily digested by restriction endonucleases, making it suitable for use in various molecular applications. Images PMID:1909713

A Microfluidic Channel Method for Rapid Drug-Susceptibility Testing of Pseudomonas aeruginosa

PubMed Central

Matsumoto, Yoshimi; Grushnikov, Andrey; Kikuchi, Kazuma; Noji, Hiroyuki; Yamaguchi, Akihito; Yagi, Yasushi

2016-01-01

The recent global increase in the prevalence of antibiotic-resistant bacteria and lack of development of new therapeutic agents emphasize the importance of selecting appropriate antimicrobials for the treatment of infections. However, to date, the development of completely accelerated drug susceptibility testing methods has not been achieved despite the availability of a rapid identification method. We proposed an innovative rapid method for drug susceptibility testing for Pseudomonas aeruginosa that provides results within 3 h. The drug susceptibility testing microfluidic (DSTM) device was prepared using soft lithography. It consisted of five sets of four microfluidic channels sharing one inlet slot, and the four channels are gathered in a small area, permitting simultaneous microscopic observation. Antimicrobials were pre-introduced into each channel and dried before use. Bacterial suspensions in cation-adjusted Mueller–Hinton broth were introduced from the inlet slot and incubated for 3 h. Susceptibilities were microscopically evaluated on the basis of differences in cell numbers and shapes between drug-treated and control cells, using dedicated software. The results of 101 clinically isolated strains of P. aeruginosa obtained using the DSTM method strongly correlated with results obtained using the ordinary microbroth dilution method. Ciprofloxacin, meropenem, ceftazidime, and piperacillin caused elongation in susceptible cells, while meropenem also induced spheroplast and bulge formation. Morphological observation could alternatively be used to determine the susceptibility of P. aeruginosa to these drugs, although amikacin had little effect on cell shape. The rapid determination of bacterial drug susceptibility using the DSTM method could also be applicable to other pathogenic species, and it could easily be introduced into clinical laboratories without the need for expensive instrumentation. PMID:26872134

Rapid analysis method for the determination of 14C specific activity in irradiated graphite

PubMed Central

Remeikis, Vidmantas; Lagzdina, Elena; Garbaras, Andrius; Gudelis, Arūnas; Garankin, Jevgenij; Juodis, Laurynas; Duškesas, Grigorijus; Lingis, Danielius; Abdulajev, Vladimir; Plukis, Artūras

2018-01-01

14C is one of the limiting radionuclides used in the categorization of radioactive graphite waste; this categorization is crucial in selecting the appropriate graphite treatment/disposal method. We propose a rapid analysis method for 14C specific activity determination in small graphite samples in the 1–100 μg range. The method applies an oxidation procedure to the sample, which extracts 14C from the different carbonaceous matrices in a controlled manner. Because this method enables fast online measurement and 14C specific activity evaluation, it can be especially useful for characterizing 14C in irradiated graphite when dismantling graphite moderator and reflector parts, or when sorting radioactive graphite waste from decommissioned nuclear power plants. The proposed rapid method is based on graphite combustion and the subsequent measurement of both CO2 and 14C, using a commercial elemental analyser and the semiconductor detector, respectively. The method was verified using the liquid scintillation counting (LSC) technique. The uncertainty of this rapid method is within the acceptable range for radioactive waste characterization purposes. The 14C specific activity determination procedure proposed in this study takes approximately ten minutes, comparing favorably to the more complicated and time consuming LSC method. This method can be potentially used to radiologically characterize radioactive waste or used in biomedical applications when dealing with the specific activity determination of 14C in the sample. PMID:29370233

Rapid analysis method for the determination of 14C specific activity in irradiated graphite.

PubMed

Remeikis, Vidmantas; Lagzdina, Elena; Garbaras, Andrius; Gudelis, Arūnas; Garankin, Jevgenij; Plukienė, Rita; Juodis, Laurynas; Duškesas, Grigorijus; Lingis, Danielius; Abdulajev, Vladimir; Plukis, Artūras

2018-01-01

14C is one of the limiting radionuclides used in the categorization of radioactive graphite waste; this categorization is crucial in selecting the appropriate graphite treatment/disposal method. We propose a rapid analysis method for 14C specific activity determination in small graphite samples in the 1-100 μg range. The method applies an oxidation procedure to the sample, which extracts 14C from the different carbonaceous matrices in a controlled manner. Because this method enables fast online measurement and 14C specific activity evaluation, it can be especially useful for characterizing 14C in irradiated graphite when dismantling graphite moderator and reflector parts, or when sorting radioactive graphite waste from decommissioned nuclear power plants. The proposed rapid method is based on graphite combustion and the subsequent measurement of both CO2 and 14C, using a commercial elemental analyser and the semiconductor detector, respectively. The method was verified using the liquid scintillation counting (LSC) technique. The uncertainty of this rapid method is within the acceptable range for radioactive waste characterization purposes. The 14C specific activity determination procedure proposed in this study takes approximately ten minutes, comparing favorably to the more complicated and time consuming LSC method. This method can be potentially used to radiologically characterize radioactive waste or used in biomedical applications when dealing with the specific activity determination of 14C in the sample.

Calibrated infrared ground/air radiometric spectrometer

NASA Astrophysics Data System (ADS)

Silk, J. K.; Schildkraut, Elliot Robert; Bauldree, Russell S.; Goodrich, Shawn M.

1996-06-01

The calibrated infrared ground/air radiometric spectrometer (CIGARS) is a new high performance, multi-purpose, multi- platform Fourier transform spectrometer (FPS) sensor. It covers the waveband from 0.2 to 12 micrometer, has spectral resolution as fine as 0.3 cm-1, and records over 100 spectra per second. Two CIGARS units are being used for observations of target signatures in the air or on the ground from fixed or moving platforms, including high performance jet aircraft. In this paper we describe the characteristics and capabilities of the CIGARS sensor, which uses four interchangeable detector modules (Si, InGaAs, InSb, and HgCdTe) and two optics modules, with internal calibration. The data recording electronics support observations of transient events, even without precise information on the timing of the event. We present test and calibration data on the sensitivity, spectral resolution, stability, and spectral rate of CIGARS, and examples of in- flight observations of real targets. We also discuss plans for adapting CIGARS for imaging spectroscopy observations, with simultaneous spectral and spatial data, by replacing the existing detectors with a focal plane array (FPA).

A COMPARISON OF TWO RAPID BIOLOGICAL ASSESSMENT SAMPLING METHODS FOR MACROINVERTEBRATES

EPA Science Inventory

In 2003, the Office of Research and Developments (ORD's) National Exposure Research Laboratory initiated a collaborative research effort with U.S. EPA Region 3 to conduct a study comparing two rapid biological assessment methods for collecting stream macroinvertebrates. One metho...

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 (0.6radiometric sensitivity of the GEO-CAPE mission in identifying the changes in bio-optical properties at top-of-atmosphere (TOA), which aids in a more lucid

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.

A radiometric model of an earth radiation budget radiometer optical system with diffuse-specular surfaces

NASA Technical Reports Server (NTRS)

Luther, M. R.

1981-01-01

The Earth Radiation Budget Experiment (ERBE) is to fly on NASA's Earth Radiation Budget Satellite (ERBS) and on NOAA F and NOAA G. Large spatial scale earth energy budget data will be derived primarily from measurements made by the ERBE nonscanning instrument (ERBE-NS). A description is given of a mathematical model capable of simulating the radiometric response of any of the ERBE-NS earth viewing channels. The model uses a Monte Carlo method to accurately account for directional distributions of emission and reflection from optical surfaces which are neither strictly diffuse nor strictly specular. The model computes radiation exchange factors among optical system components, and determines the distribution in the optical system of energy from an outside source. Attention is also given to an approach for implementing the model and results obtained from the implementation.

RLS Instrument Radiometric Model: Instrument performance theoretical evaluation and experimental checks

NASA Astrophysics Data System (ADS)

Quintana, César; Ramos, Gonzalo; Moral, Andoni; Rodriguez, Jose Antonio; Pérez, Carlos; Hutchinson, Ian; INGLEY, Richard; Rull, Fernando

2016-10-01

Raman Laser Spectrometer (RLS) is one of the Pasteur payload instruments located at the Rover of the ExoMars mission and within the ESA's Aurora Exploration Programme. RLS will explore the Mars surface composition through the Raman spectroscopy technique. The instrument is divided into several units: a laser for Raman emission stimulation, an internal optical head (iOH) for sample excitation and for Raman emission recovering, a spectrometer with a CCD located at its output (SPU), the optical harness (OH) for the units connection, from the laser to the excitation path of the iOH and from the iOH reception path to the spectrometer, and the corresponding electronics for the CCD operation.Due to the variability of the samples to be analyzed on Mars, a radiometry prediction for the instrument performance results to be of the critical importance. In such a framework, and taking into account the SNR (signal to noise ratio) required for the achievement of successful results from the scientific point of view (a proper information about the Mars surface composition), a radiometric model has been developed to provide the requirements for the different units, i.e. the laser irradiance, the iOH, OH, and SPU throughputs, and the samples that will be possible to be analyzed in terms of its Raman emission and the relationship of the Raman signal with respect to fluorescence emission, among others.The radiometric model fundamentals (calculations and approximations), as well as the first results obtained during the bread board characterization campaign are here reported on.

The Rapid-Heat LAMPellet Method: A Potential Diagnostic Method for Human Urogenital Schistosomiasis

PubMed Central

Carranza-Rodríguez, Cristina; Pérez-Arellano, José Luis; Vicente, Belén; López-Abán, Julio; Muro, Antonio

2015-01-01

Background Urogenital schistosomiasis due to Schistosoma haematobium is a serious underestimated public health problem affecting 112 million people - particularly in sub-Saharan Africa. Microscopic examination of urine samples to detect parasite eggs still remains as definitive diagnosis. This work was focussed on developing a novel loop-mediated isothermal amplification (LAMP) assay for detection of S. haematobium DNA in human urine samples as a high-throughput, simple, accurate and affordable diagnostic tool to use in diagnosis of urogenital schistosomiasis. Methodology/Principal Findings A LAMP assay targeting a species specific sequence of S. haematobium ribosomal intergenic spacer was designed. The effectiveness of our LAMP was assessed in a number of patients´ urine samples with microscopy confirmed S. haematobium infection. For potentially large-scale application in field conditions, different DNA extraction methods, including a commercial kit, a modified NaOH extraction method and a rapid heating method were tested using small volumes of urine fractions (whole urine, supernatants and pellets). The heating of pellets from clinical samples was the most efficient method to obtain good-quality DNA detectable by LAMP. The detection limit of our LAMP was 1 fg/µL of S. haematobium DNA in urine samples. When testing all patients´ urine samples included in our study, diagnostic parameters for sensitivity and specificity were calculated for LAMP assay, 100% sensitivity (95% CI: 81.32%-100%) and 86.67% specificity (95% CI: 75.40%-94.05%), and also for microscopy detection of eggs in urine samples, 69.23% sensitivity (95% CI: 48.21% -85.63%) and 100% specificity (95% CI: 93.08%-100%). Conclusions/Significance We have developed and evaluated, for the first time, a LAMP assay for detection of S. haematobium DNA in heated pellets from patients´ urine samples using no complicated requirement procedure for DNA extraction. The procedure has been named the Rapid

[Experimental rationale for the parameters of a rapid method for oxidase activity determination].

PubMed

Butorina, N N

2010-01-01

Experimental rationale is provided for the parameters of a rapid (1-2-min) test to concurrently determine the oxidase activity of all bacteria grown on the membrane filter after water filtration. Oxidase reagents that are the aqueous solutions of tetramethyl-p-phenylenediamine dihydrochloride and demethyl-p-phenylenediamine dihydrochloride have been first ascertained to exert no effect on the viability and enzymatic activity of bacteria after one-hour contact. An algorithm has been improved for the rapid oxidase activity test: the allowable time for bacteria to contact oxidase reagents and procedures for minimizing the effect on bacterial biochemical activity following the contact. An accelerated method based on lactose medium with tergitol 7 and Endo agar has been devised to determine coliform bacteria, by applying the rapid oxidase test: the time of a final response is 18-24 hours. The method has been included into GOST 52426-2005.

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.

Effectiveness of Rapid Cooling as a Method of Euthanasia for Young Zebrafish (Danio rerio).

PubMed

Wallace, Chelsea K; Bright, Lauren A; Marx, James O; Andersen, Robert P; Mullins, Mary C; Carty, Anthony J

2018-01-01

Despite increased use of zebrafish (Danio rerio) in biomedical research, consistent information regarding appropriate euthanasia methods, particularly for embryos, is sparse. Current literature indicates that rapid cooling is an effective method of euthanasia for adult zebrafish, yet consistent guidelines regarding zebrafish younger than 6 mo are unavailable. This study was performed to distinguish the age at which rapid cooling is an effective method of euthanasia for zebrafish and the exposure times necessary to reliably euthanize zebrafish using this method. Zebrafish at 3, 4, 7, 14, 16, 19, 21, 28, 60, and 90 d postfertilization (dpf) were placed into an ice water bath for 5, 10, 30, 45, or 60 min (n = 12 to 40 per group). In addition, zebrafish were placed in ice water for 12 h (age ≤14 dpf) or 30 s (age ≥14 dpf). After rapid cooling, fish were transferred to a recovery tank and the number of fish alive at 1, 4, and 12-24 h after removal from ice water was documented. Euthanasia was defined as a failure when evidence of recovery was observed at any point after removal from ice water. Results showed that younger fish required prolonged exposure to rapid cooling for effective euthanasia, with the required exposure time decreasing as fish age. Although younger fish required long exposure times, animals became immobilized immediately upon exposure to the cold water, and behavioral indicators of pain or distress rarely occurred. We conclude that zebrafish 14 dpf and younger require as long as 12 h, those 16 to 28 dpf of age require 5 min, and those older than 28 dpf require 30 s minimal exposure to rapid cooling for reliable euthanasia.

Method for rapid high-frequency seismogram calculation

NASA Astrophysics Data System (ADS)

Stabile, Tony Alfredo; De Matteis, Raffaella; Zollo, Aldo

2009-02-01

We present a method for rapid, high-frequency seismogram calculation that makes use of an algorithm to automatically generate an exhaustive set of seismic phases with an appreciable amplitude on the seismogram. The method uses a hierarchical order of ray and seismic-phase generation, taking into account some existing constraints for ray paths and some physical constraints. To compute synthetic seismograms, the COMRAD code (from the Italian: "COdice Multifase per il RAy-tracing Dinamico") uses as core a dynamic ray-tracing code. To validate the code, we have computed in a layered medium synthetic seismograms using both COMRAD and a code that computes the complete wave field by the discrete wave number method. The seismograms are compared according to a time-frequency misfit criteria based on the continuous wavelet transform of the signals. Although the number of phases is considerably reduced by the selection criteria, the results show that the loss in amplitude on the whole seismogram is negligible. Moreover, the time for the computing of the synthetics using the COMRAD code (truncating the ray series at the 10th generation) is 3-4-fold less than that needed for the AXITRA code (up to a frequency of 25 Hz).

Landsat-7 ETM+ on-orbit reflective-band radiometric characterization

USGS Publications Warehouse

Scaramuzza, P.L.; Markham, B.L.; Barsi, J.A.; Kaita, E.

2004-01-01

The Landsat-7 Enhanced Thematic Mapper Plus (ETM+) has been and continues to be radiometrically characterized using the Image Assessment System (IAS), a component of the Landsat-7 Ground System. Key radiometric properties analyzed include: overall, coherent, and impulse noise; bias stability; relative gain stability; and other artifacts. The overall instrument noise is characterized across the dynamic range of the instrument during solar diffuser deployments. Less than 1% per year increases are observed in signal-independent (dark) noise levels, while signal-dependent noise is stable with time. Several coherent noise sources exist in ETM+ data with scene-averaged magnitudes of up to 0.4 DN, and a noise component at 20 kHz whose magnitude varies across the scan and peaks at the image edges. Bit-flip noise does not exist on the ETM+. However, impulse noise due to charged particle hits on the detector array has been discovered. The instrument bias is measured every scan line using a shutter. Most bands show less than 0.1 DN variations in bias across the instrument lifetime. The panchromatic band is the exception, where the variation approaches 2 DN and is related primarily to temperature. The relative gains of the detectors, i.e., each detector's gain relative to the band average gain, have been stable to /spl plusmn/0.1% over the mission life. Two exceptions to this stability include band 2 detector 2, which dropped about 1% in gain about 3.5 years after launch and stabilized, and band 7 detector 5, which has changed several tenths of a percent several times since launch. Memory effect and scan-correlated shift, a hysteresis and a random change in bias between multiple states, respectively, both of which have been observed in previous Thematic Mapper sensors, have not been convincingly found in ETM+ data. Two artifacts, detector ringing and "oversaturation", affect a small amount of ETM+ data.

Rapid surface enhanced Raman scattering detection method for chloramphenicol residues.

PubMed

Ji, Wei; Yao, Weirong

2015-06-05

Chloramphenicol (CAP) is a widely used amide alcohol antibiotics, which has been banned from using in food producing animals in many countries. In this study, surface enhanced Raman scattering (SERS) coupled with gold colloidal nanoparticles was used for the rapid analysis of CAP. Density functional theory (DFT) calculations were conducted with Gaussian 03 at the B3LYP level using the 3-21G(d) and 6-31G(d) basis sets to analyze the assignment of vibrations. Affirmatively, the theoretical Raman spectrum of CAP was in complete agreement with the experimental spectrum. They both exhibited three strong peaks characteristic of CAP at 1104 cm(-1), 1344 cm(-1), 1596 cm(-1), which were used for rapid qualitative analysis of CAP residues in food samples. The use of SERS as a method for the measurements of CAP was explored by comparing use of different solvents, gold colloidal nanoparticles concentration and absorption time. The method of the detection limit was determined as 0.1 μg/mL using optimum conditions. The Raman peak at 1344 cm(-1) was used as the index for quantitative analysis of CAP in food samples, with a linear correlation of R(2)=0.9802. Quantitative analysis of CAP residues in foods revealed that the SERS technique with gold colloidal nanoparticles was sensitive and of a good stability and linear correlation, and suited for rapid analysis of CAP residue in a variety of food samples. Copyright © 2015 Elsevier B.V. All rights reserved.

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.

A rapid method for preparation of the cerebrospinal fluid proteome.

PubMed

Larssen, Eivind; Brede, Cato; Hjelle, Anne Bjørnstad; Øysaed, Kjell Birger; Tjensvoll, Anne Bolette; Omdal, Roald; Ruoff, Peter

2015-01-01

The cerebrospinal fluid (CSF) proteome is of great interest for investigation of diseases and conditions involving the CNS. However, the presence of high-abundance proteins (HAPs) can interfere with the detection of low-abundance proteins, potentially hindering the discovery of new biomarkers. Therefore, an assessment of the CSF subproteome composition requires depletion strategies. Existing methods are time consuming, often involving multistep protocols. Here, we present a rapid, accurate, and reproducible method for preparing the CSF proteome, which allows the identification of a high number of proteins. This method involves acetonitrile (ACN) precipitation for depleting HAPs, followed by immediate trypsination. As an example, we demonstrate that this method allows discrimination between multiple sclerosis patients and healthy subjects. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.

Retrieval of effective cloud field parameters from radiometric data

NASA Astrophysics Data System (ADS)

Paulescu, Marius; Badescu, Viorel; Brabec, Marek

2017-06-01

Clouds play a key role in establishing the Earth's climate. Real cloud fields are very different and very complex in both morphological and microphysical senses. Consequently, the numerical description of the cloud field is a critical task for accurate climate modeling. This study explores the feasibility of retrieving the effective cloud field parameters (namely the cloud aspect ratio and cloud factor) from systematic radiometric measurements at high frequency (measurement is taken every 15 s). Two different procedures are proposed, evaluated, and discussed with respect to both physical and numerical restrictions. None of the procedures is classified as best; therefore, the specific advantages and weaknesses are discussed. It is shown that the relationship between the cloud shade and point cloudiness computed using the estimated cloud field parameters recovers the typical relationship derived from measurements.

Uncooled radiometric camera performance

NASA Astrophysics Data System (ADS)

Meyer, Bill; Hoelter, T.

1998-07-01

Thermal imaging equipment utilizing microbolometer detectors operating at room temperature has found widespread acceptance in both military and commercial applications. Uncooled camera products are becoming effective solutions to applications currently using traditional, photonic infrared sensors. The reduced power consumption and decreased mechanical complexity offered by uncooled cameras have realized highly reliable, low-cost, hand-held instruments. Initially these instruments displayed only relative temperature differences which limited their usefulness in applications such as Thermography. Radiometrically calibrated microbolometer instruments are now available. The ExplorIR Thermography camera leverages the technology developed for Raytheon Systems Company's first production microbolometer imaging camera, the Sentinel. The ExplorIR camera has a demonstrated temperature measurement accuracy of 4 degrees Celsius or 4% of the measured value (whichever is greater) over scene temperatures ranges of minus 20 degrees Celsius to 300 degrees Celsius (minus 20 degrees Celsius to 900 degrees Celsius for extended range models) and camera environmental temperatures of minus 10 degrees Celsius to 40 degrees Celsius. Direct temperature measurement with high resolution video imaging creates some unique challenges when using uncooled detectors. A temperature controlled, field-of-view limiting aperture (cold shield) is not typically included in the small volume dewars used for uncooled detector packages. The lack of a field-of-view shield allows a significant amount of extraneous radiation from the dewar walls and lens body to affect the sensor operation. In addition, the transmission of the Germanium lens elements is a function of ambient temperature. The ExplorIR camera design compensates for these environmental effects while maintaining the accuracy and dynamic range required by today's predictive maintenance and condition monitoring markets.

Rapid high temperature field test method for evaluation of geothermal calcite scale inhibitors

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

Asperger, R.G.

1982-08-01

A test method is described which allows the rapid field testing of calcite scale inhibitors in high- temperature geothermal brines. Five commercial formulations, chosen on the basis of laboratory screening tests, were tested in brines with low total dissolved solids at ca 500 F. Four were found to be effective; of these, 2 were found to be capable of removing recently deposited scale. One chemical was tested in the full-flow brine line for 6 wks. It was shown to stop a severe surface scaling problem at the well's control valve, thus proving the viability of the rapid test method. (12more » refs.)« less

A Rapid Method for Engineering Recombinant Polioviruses or Other Enteroviruses.

PubMed

Bessaud, Maël; Pelletier, Isabelle; Blondel, Bruno; Delpeyroux, Francis

2016-01-01

The cloning of large enterovirus RNA sequences is labor-intensive because of the frequent instability in bacteria of plasmidic vectors containing the corresponding cDNAs. In order to circumvent this issue we have developed a PCR-based method that allows the generation of highly modified or chimeric full-length enterovirus genomes. This method relies on fusion PCR which enables the concatenation of several overlapping cDNA amplicons produced separately. A T7 promoter sequence added upstream the fusion PCR products allows its transcription into infectious genomic RNAs directly in transfected cells constitutively expressing the phage T7 RNA polymerase. This method permits the rapid recovery of modified viruses that can be subsequently amplified on adequate cell-lines.

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.

Rapid qualitative research methods during complex health emergencies: A systematic review of the literature.

PubMed

Johnson, Ginger A; Vindrola-Padros, Cecilia

2017-09-01

The 2013-2016 Ebola outbreak in West Africa highlighted both the successes and limitations of social science contributions to emergency response operations. An important limitation was the rapid and effective communication of study findings. A systematic review was carried out to explore how rapid qualitative methods have been used during global heath emergencies to understand which methods are commonly used, how they are applied, and the difficulties faced by social science researchers in the field. We also asses their value and benefit for health emergencies. The review findings are used to propose recommendations for qualitative research in this context. Peer-reviewed articles and grey literature were identified through six online databases. An initial search was carried out in July 2016 and updated in February 2017. The PRISMA checklist was used to guide the reporting of methods and findings. The articles were assessed for quality using the MMAT and AACODS checklist. From an initial search yielding 1444 articles, 22 articles met the criteria for inclusion. Thirteen of the articles were qualitative studies and nine used a mixed-methods design. The purpose of the rapid studies included: the identification of causes of the outbreak, and assessment of infrastructure, control strategies, health needs and health facility use. The studies varied in duration (from 4 days to 1 month). The main limitations identified by the authors were: the low quality of the collected data, small sample sizes, and little time for cross-checking facts with other data sources to reduce bias. Rapid qualitative methods were seen as beneficial in highlighting context-specific issues that need to be addressed locally, population-level behaviors influencing health service use, and organizational challenges in response planning and implementation. Recommendations for carrying out rapid qualitative research in this context included the early designation of community leaders as a point of

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.

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.

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.

Rapid methods for jugular bleeding of dogs requiring one technician.

PubMed

Frisk, C S; Richardson, M R

1979-06-01

Two methods were used to collect blood from the jugular vein of dogs. In both techniques, only one technician was required. A rope with a slip knot was placed around the base of the neck to assist in restraint and act as a tourniquet for the vein. The technician used one hand to restrain the dog by the muzzle and position the head. The other hand was used for collecting the sample. One of the methods could be accomplished with the dog in its cage. The bleeding techniques were rapid, requiring approximately 1 minute per dog.

Mixing geometric and radiometric features for change classification

NASA Astrophysics Data System (ADS)

Fournier, Alexandre; Descombes, Xavier; Zerubia, Josiane

2008-02-01

Most basic change detection algorithms use a pixel-based approach. Whereas such approach is quite well defined for monitoring important area changes (such as urban growth monitoring) in low resolution images, an object based approach seems more relevant when the change detection is specifically aimed toward targets (such as small buildings and vehicles). In this paper, we present an approach that mixes radiometric and geometric features to qualify the changed zones. The goal is to establish bounds (appearance, disappearance, substitution ...) between the detected changes and the underlying objects. We proceed by first clustering the change map (containing each pixel bitemporal radiosity) in different classes using the entropy-kmeans algorithm. Assuming that most man-made objects have a polygonal shape, a polygonal approximation algorithm is then used in order to characterize the resulting zone shapes. Hence allowing us to refine the primary rough classification, by integrating the polygon orientations in the state space. Tests are currently conducted on Quickbird data.

Aerial radiometric and magnetic reconnaissance survey of portions of Kentucky, Virginia, and West Virginia: Jenkins Quadrangle. Final report

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

Not Available

The results of a high-sensitivity, aerial, gamma-ray spectrometer and magnetometer survey of the Jenkins Quadrangle, Kentucky, Virginia, West Virginia, are presented. Instrumentation and methods are described in Volume 1 of this final report. This work was done as part of the US Department of Energy National Uranium Resource Evaluation (NURE) Program. Statistical and geological analysis of the radiometric data revealed 52 anomalies worthy of field checking as possible prospects. Twelve anomalies coincide with cultural features that may be major contributors to their anomalous values. Eight anomalies may be due to late dissipation of low-level inversion conditions and low topographic location.more » Pennsylvanian and Mississippian sandstone and shales have the greatest concentration of anomalies.« less

Method for the melting of metals

DOEpatents

White, Jack C.; Traut, Davis E.

1992-01-01

A method of quantitatively determining the molten pool configuration in melting of metals. The method includes the steps of introducing hafnium metal seeds into a molten metal pool at intervals to form ingots, neutron activating the ingots and determining the hafnium location by radiometric means. Hafnium possesses exactly the proper metallurgical and radiochemical properties for this use.

Method for the rapid synthesis of large quantities of metal oxide nanowires at low temperatures

DOEpatents

Sunkara, Mahendra Kumar [Louisville, KY; Vaddiraju, Sreeram [Mountain View, CA; Mozetic, Miran [Ljubljan, SI; Cvelbar, Uros [Idrija, SI

2009-09-22

A process for the rapid synthesis of metal oxide nanoparticles at low temperatures and methods which facilitate the fabrication of long metal oxide nanowires. The method is based on treatment of metals with oxygen plasma. Using oxygen plasma at low temperatures allows for rapid growth unlike other synthesis methods where nanomaterials take a long time to grow. Density of neutral oxygen atoms in plasma is a controlling factor for the yield of nanowires. The oxygen atom density window differs for different materials. By selecting the optimal oxygen atom density for various materials the yield can be maximized for nanowire synthesis of the metal.

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.

Estimation of the cloud transmittance from radiometric measurements at the ground level

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

Costa, Dario; Mares, Oana, E-mail: mareshoana@yahoo.com

2014-11-24

The extinction of solar radiation due to the clouds is more significant than due to any other atmospheric constituent, but it is always difficult to be modeled because of the random distribution of clouds on the sky. Moreover, the transmittance of a layer of clouds is in a very complex relation with their type and depth. A method for estimating cloud transmittance was proposed in Paulescu et al. (Energ. Convers. Manage, 75 690–697, 2014). The approach is based on the hypothesis that the structure of the cloud covering the sun at a time moment does not change significantly in amore » short time interval (several minutes). Thus, the cloud transmittance can be calculated as the estimated coefficient of a simple linear regression for the computed versus measured solar irradiance in a time interval Δt. The aim of this paper is to optimize the length of the time interval Δt. Radiometric data measured on the Solar Platform of the West University of Timisoara during 2010 at a frequency of 1/15 seconds are used in this study.« less

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

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.

Intelligent Visual Input: A Graphical Method for Rapid Entry of Patient-Specific Data

PubMed Central

Bergeron, Bryan P.; Greenes, Robert A.

1987-01-01

Intelligent Visual Input (IVI) provides a rapid, graphical method of data entry for both expert system interaction and medical record keeping purposes. Key components of IVI include: a high-resolution graphic display; an interface supportive of rapid selection, i.e., one utilizing a mouse or light pen; algorithm simplification modules; and intelligent graphic algorithm expansion modules. A prototype IVI system, designed to facilitate entry of physical exam findings, is used to illustrates the potential advantages of this approach.

Overview of radiometric ages in three allochthonous belts of Northern Venezuela: Old ones, new ones, and their impact on regional geology

USGS Publications Warehouse

Sisson, V.B.; Ave Lallemant, H.G.; Ostos, M.; Blythe, A.E.; Snee, L.W.; Copeland, Peter; Wright, J.E.; Donelick, R.A.; Guth, L.R.

2005-01-01

The margin of northern Venezuela is a complex zone representing the orogenic events from basement formation to subsequent subduction and exhumation during transpressional collision. This boundary zone has six east-west-trending belts that each record a different segment of its development. This geologic complexity requires radiometric ages to unravel, and we herein provide 48 new ages including U-Pb (4), Rb-Sr (2), 40Ar/39Ar (24), zircon and apatite fission-track (17), and 14C (1) ages to constrain the evolution of three of these belts. These three belts are the Cordillera de la Costa, Caucagua-El Tinaco, and Serran??a del Interior belts. In the Cordillera de la Costa belt, U-Pb geochronologic data indicate portions of the basement igneous and metaigneous rocks formed in the Cambro-Ordovician (513-471 Ma). New 40Ar/39Ar data from Margarita Island indicate that some of the subduction complex was rapidly cooled and exhumed, whereas other portions indicate slower cooling. This contrasts with new 40Ar/39Ar data from the Puerto Cabello. ?? 2005 Geological Society of America.

Geometric & radiometric vignetting associated with a 72-facet, off-axis, polygon mirror for swept source optical coherence tomography (SS-OCT)

NASA Astrophysics Data System (ADS)

Everson, Michael; Duma, Virgil-Florin; Dobre, George

2017-01-01

Optical Coherence Tomography (OCT) has a broad range of applications in 2D and volumetric imaging of micron scale structures typically used on inaccessible objects such as the retina of the eye. This report focuses on Swept Source OCT (SS-OCT), favoured for its faster scanning speeds and therefore faster data acquisition (highly favourable when imaging live patients). SS-OCT relies on the scanning of a narrow laser line at speeds typically in excess of 100 kHz. We have employed ZemaxTM ray tracing software to simulate one method of splitting the spectrum of a broadband, near-infrared source, into its component wavelengths by reflecting the spectrum from an off-axis, 72-facet polygon mirror at a frequency of 48 kHz. We specifically addressed the geometric and radiometric vignetting associated with the reflected spectrum off an individual mirrored facet and how this may impose limitations to the incident beam size and hence lead to a loss in the power available from the source. It was found that for certain configurations up to 44% of the light was lost at the edges of the spectrum due to both radiometric and geometric vignetting, which may result in an effective swept range of <50 nm from an initial bandwidth of 100 nm. Our simulations account for real refractive errors and losses in the beam caused by lens aberrations, and produce a model of the sampling function of wavelength against time.

The Importance of Post-Launch, On-Orbit Absolute Radiometric Calibration for Remote Sensing Applications

NASA Astrophysics Data System (ADS)

Kuester, M. A.

2015-12-01

Remote sensing is a powerful tool for monitoring changes on the surface of the Earth at a local or global scale. The use of data sets from different sensors across many platforms, or even a single sensor over time, can bring a wealth of information when exploring anthropogenic changes to the environment. For example, variations in crop yield and health for a specific region can be detected by observing changes in the spectral signature of the particular species under study. However, changes in the atmosphere, sun illumination and viewing geometries during image capture can result in inconsistent image data, hindering automated information extraction. Additionally, an incorrect spectral radiometric calibration will lead to false or misleading results. It is therefore critical that the data being used are normalized and calibrated on a regular basis to ensure that physically derived variables are as close to truth as is possible. Although most earth observing sensors are well-calibrated in a laboratory prior to launch, a change in the radiometric response of the system is inevitable due to thermal, mechanical or electrical effects caused during the rigors of launch or by the space environment itself. Outgassing and exposure to ultra-violet radiation will also have an effect on the sensor's filter responses. Pre-launch lamps and other laboratory calibration systems can also fall short in representing the actual output of the Sun. A presentation of the differences in the results of some example cases (e.g. geology, agriculture) derived for science variables using pre- and post-launch calibration will be presented using DigitalGlobe's WorldView-3 super spectral sensor, with bands in the visible and near infrared, as well as in the shortwave infrared. Important defects caused by an incomplete (i.e. pre-launch only) calibration will be discussed using validation data where available. In addition, the benefits of using a well-validated surface reflectance product will be

Radiometric Calibration Techniques for Signal-of-Opportunity Reflectometers

NASA Technical Reports Server (NTRS)

Piepmeier, Jeffrey R.; Shah, Rashmi; Deshpande, Manohar; Johnson, Carey

2014-01-01

Bi-static reflection measurements utilizing global navigation satellite service (GNSS) or other signals of opportunity (SoOp) can be used to sense ocean and terrestrial surface properties. End-to-end calibration of GNSS-R has been performed using well-characterized reflection surface (e.g., water), direct path antenna, and receiver gain characterization. We propose an augmented approach using on-board receiver electronics for radiometric calibration of SoOp reflectometers utilizing direct and reflected signal receiving antennas. The method calibrates receiver and correlator gains and offsets utilizing a reference switch and common noise source. On-board electronic calibration sources, such as reference switches, noise diodes and loop-back circuits, have shown great utility in stabilizing total power and correlation microwave radiometer and scatterometer receiver electronics in L-band spaceborne instruments. Application to SoOp instruments is likely to bring several benefits. For example, application to provide short and long time scale calibration stability of the direct path channel, especially in low signal-to-noise ratio configurations, is directly analogous to the microwave radiometer problem. The direct path channel is analogous to the loopback path in a scatterometer to provide a reference of the transmitted power, although the receiver is independent from the reflected path channel. Thus, a common noise source can be used to measure the gain ratio of the two paths. Using these techniques long-term (days to weeks) calibration stability of spaceborne L-band scatterometer and radiometer has been achieved better than 0.1. Similar long-term stability would likely be needed for a spaceborne reflectometer mission to measure terrestrial properties such as soil moisture.

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.

A rapid analytical method for predicting the oxygen demand of wastewater.

PubMed

Fogelman, Shoshana; Zhao, Huijun; Blumenstein, Michael

2006-11-01

In this study, an investigation was undertaken to determine whether the predictive accuracy of an indirect, multiwavelength spectroscopic technique for rapidly determining oxygen demand (OD) values is affected by the use of unfiltered and turbid samples, as well as by the use of absorbance values measured below 200 nm. The rapid OD technique was developed that uses UV-Vis spectroscopy and artificial neural networks (ANNs) to indirectly determine chemical oxygen demand (COD) levels. It was found that the most accurate results were obtained when a spectral range of 190-350 nm was provided as data input to the ANN, and when using unfiltered samples below a turbidity range of 150 NTU. This is because high correlations of above 0.90 were obtained with the data using the standard COD method. This indicates that samples can be measured directly without the additional need for preprocessing by filtering. Samples with turbidity values higher than 150 NTU were found to produce poor correlations with the standard COD method, which made them unsuitable for accurate, real-time, on-line monitoring of OD levels.

A modified cluster-sampling method for post-disaster rapid assessment of needs.

PubMed Central

Malilay, J.; Flanders, W. D.; Brogan, D.

1996-01-01

The cluster-sampling method can be used to conduct rapid assessment of health and other needs in communities affected by natural disasters. It is modelled on WHO's Expanded Programme on Immunization method of estimating immunization coverage, but has been modified to provide (1) estimates of the population remaining in an area, and (2) estimates of the number of people in the post-disaster area with specific needs. This approach differs from that used previously in other disasters where rapid needs assessments only estimated the proportion of the population with specific needs. We propose a modified n x k survey design to estimate the remaining population, severity of damage, the proportion and number of people with specific needs, the number of damaged or destroyed and remaining housing units, and the changes in these estimates over a period of time as part of the survey. PMID:8823962

Autoclave method for rapid preparation of bacterial PCR-template DNA.

PubMed

Simmon, Keith E; Steadman, Dewey D; Durkin, Sarah; Baldwin, Amy; Jeffrey, Wade H; Sheridan, Peter; Horton, Rene; Shields, Malcolm S

2004-02-01

An autoclave method for preparing bacterial DNA for PCR template is presented, it eliminates the use of detergents, organic solvents, and mechanical cellular disruption approaches, thereby significantly reducing processing time and costs while increasing reproducibility. Bacteria are lysed by rapid heating and depressurization in an autoclave. The lysate, cleared by microcentrifugation, was either used directly in the PCR reaction, or concentrated by ultrafiltration. This approach was compared with seven established methods of DNA template preparation from four bacterial sources which included boiling Triton X-100 and SDS, bead beating, lysozyme/proteinase K, and CTAB lysis method components. Bacteria examined were Enterococcus and Escherichia coli, a natural marine bacterial community and an Antarctic cyanobacterial-mat. DNAs were tested for their suitability as PCR templates by repetitive element random amplified polymorphic DNA (RAPD) and denaturing gradient gel electrophoresis (DGGE) analysis. The autoclave method produced PCR amplifiable template comparable or superior to the other methods, with greater reproducibility, much shorter processing time, and at a significantly lower cost.

Blast investigation by fast multispectral radiometric analysis

NASA Astrophysics Data System (ADS)

Devir, A. D.; Bushlin, Y.; Mendelewicz, I.; Lessin, A. B.; Engel, M.

2011-06-01

Knowledge regarding the processes involved in blasts and detonations is required in various applications, e.g. missile interception, blasts of high-explosive materials, final ballistics and IED identification. Blasts release large amount of energy in short time duration. Some part of this energy is released as intense radiation in the optical spectral bands. This paper proposes to measure the blast radiation by a fast multispectral radiometer. The measurement is made, simultaneously, in appropriately chosen spectral bands. These spectral bands provide extensive information on the physical and chemical processes that govern the blast through the time-dependence of the molecular and aerosol contributions to the detonation products. Multi-spectral blast measurements are performed in the visible, SWIR and MWIR spectral bands. Analysis of the cross-correlation between the measured multi-spectral signals gives the time dependence of the temperature, aerosol and gas composition of the blast. Farther analysis of the development of these quantities in time may indicate on the order of the detonation and amount and type of explosive materials. Examples of analysis of measured explosions are presented to demonstrate the power of the suggested fast multispectral radiometric analysis approach.

A Direct and Rapid Method to Determine Cyanide in Urine by Capillary Electrophoresis

PubMed Central

Zhang, Qiyang; Maddukuri, Naveen; Gong, Maojun

2015-01-01

Cyanides are poisonous chemicals that widely exist in nature and industrial processes as well as accidental fires. Rapid and accurate determination of cyanide exposure would facilitate forensic investigation, medical diagnosis, and chronic cyanide monitoring. Here, a rapid and direct method was developed for the determination of cyanide ions in urinary samples. This technique was based on an integrated capillary electrophoresis system coupled with laser-induced fluorescence (LIF) detection. Cyanide ions were derivatized with naphthalene-2,3-dicarboxaldehyde (NDA) and a primary amine (glycine) for LIF detection. Three separate reagents, NDA, glycine, and cyanide sample, were mixed online, which secured uniform conditions between samples for cyanide derivatization and reduced the risk of precipitation formation of mixtures. Conditions were optimized; the derivatization was completed in 2-4 minutes, and the separation was observed in 25 s. The limit of detection (LOD) was 4.0 nM at 3-fold signal-to-noise ratio for standard cyanide in buffer. The cyanide levels in urine samples from smokers and non-smokers were determined by using the method of standard addition, which demonstrated significant difference of cyanide levels in urinary samples from the two groups of people. The developed method was rapid and accurate, and is anticipated to be applicable to cyanide detection in waste water with appropriate modification. PMID:26342870

A direct and rapid method to determine cyanide in urine by capillary electrophoresis.

PubMed

Zhang, Qiyang; Maddukuri, Naveen; Gong, Maojun

2015-10-02

Cyanides are poisonous chemicals that widely exist in nature and industrial processes as well as accidental fires. Rapid and accurate determination of cyanide exposure would facilitate forensic investigation, medical diagnosis, and chronic cyanide monitoring. Here, a rapid and direct method was developed for the determination of cyanide ions in urinary samples. This technique was based on an integrated capillary electrophoresis system coupled with laser-induced fluorescence (LIF) detection. Cyanide ions were derivatized with naphthalene-2,3-dicarboxaldehyde (NDA) and a primary amine (glycine) for LIF detection. Three separate reagents, NDA, glycine, and cyanide sample, were mixed online, which secured uniform conditions between samples for cyanide derivatization and reduced the risk of precipitation formation of mixtures. Conditions were optimized; the derivatization was completed in 2-4min, and the separation was observed in 25s. The limit of detection (LOD) was 4.0nM at 3-fold signal-to-noise ratio for standard cyanide in buffer. The cyanide levels in urine samples from smokers and non-smokers were determined by using the method of standard addition, which demonstrated significant difference of cyanide levels in urinary samples from the two groups of people. The developed method was rapid and accurate, and is anticipated to be applicable to cyanide detection in waste water with appropriate modification. Published by Elsevier B.V.

An optimized rapid bisulfite conversion method with high recovery of cell-free DNA.

PubMed

Yi, Shaohua; Long, Fei; Cheng, Juanbo; Huang, Daixin

2017-12-19

Methylation analysis of cell-free DNA is a encouraging tool for tumor diagnosis, monitoring and prognosis. Sensitivity of methylation analysis is a very important matter due to the tiny amounts of cell-free DNA available in plasma. Most current methods of DNA methylation analysis are based on the difference of bisulfite-mediated deamination of cytosine between cytosine and 5-methylcytosine. However, the recovery of bisulfite-converted DNA based on current methods is very poor for the methylation analysis of cell-free DNA. We optimized a rapid method for the crucial steps of bisulfite conversion with high recovery of cell-free DNA. A rapid deamination step and alkaline desulfonation was combined with the purification of DNA on a silica column. The conversion efficiency and recovery of bisulfite-treated DNA was investigated by the droplet digital PCR. The optimization of the reaction results in complete cytosine conversion in 30 min at 70 °C and about 65% of recovery of bisulfite-treated cell-free DNA, which is higher than current methods. The method allows high recovery from low levels of bisulfite-treated cell-free DNA, enhancing the analysis sensitivity of methylation detection from cell-free DNA.

Rapid direct methods for enumeration of specific, active bacteria in water and biofilms

NASA Technical Reports Server (NTRS)

McFeters, G. A.; Pyle, B. H.; Lisle, J. T.; Broadaway, S. C.

1999-01-01

Conventional methods for detecting indicator and pathogenic bacteria in water may underestimate the actual population due to sublethal environmental injury, inability of the target bacteria to take up nutrients and other physiological factors which reduce bacterial culturability. Rapid and direct methods are needed to more accurately detect and enumerate active bacteria. Such a methodological advance would provide greater sensitivity in assessing the microbiological safety of water and food. The principle goal of this presentation is to describe novel approaches we have formulated for the rapid and simultaneous detection of bacteria plus the determination of their physiological activity in water and other environmental samples. The present version of our method involves the concentration of organisms by membrane filtration or immunomagnetic separation and combines an intracellular fluorochrome (CTC) for assessment of respiratory activity plus fluorescent-labelled antibody detection of specific bacteria. This approach has also been successfully used to demonstrate spatial and temporal heterogeneities of physiological activities in biofilms when coupled with cryosectioning. Candidate physiological stains include those capable of determining respiratory activity, membrane potential, membrane integrity, growth rate and cellular enzymatic activities. Results obtained thus far indicate that immunomagnetic separation can provide a high degree of sensitivity in the recovery of seeded target bacteria (Escherichia coli O157:H7) in water and hamburger. The captured and stained target bacteria are then enumerated by either conventional fluorescence microscopy or ChemScan(R), a new instrument that is very sensitive and rapid. The ChemScan(R) laser scanning instrument (Chemunex, Paris, France) provides the detection of individual fluorescently labelled bacterial cells using three emission channels in less than 5 min. A high degree of correlation has been demonstrated between

An efficient and rapid transgenic pollen screening and detection method using flow cytometry.

PubMed

Moon, Hong S; Eda, Shigetoshi; Saxton, Arnold M; Ow, David W; Stewart, C Neal

2011-01-01

Assaying for transgenic pollen, a major vector of transgene flow, provides valuable information and essential data for the study of gene flow and assessing the effectiveness of transgene containment. Most studies have employed microscopic screening methods or progeny analyses to estimate the frequency of transgenic pollen. However, these methods are time-consuming and laborious when large numbers of pollen grains must be analyzed to look for rare transgenic pollen grains. Thus, there is an urgent need for the development of a simple, rapid, and high throughput analysis method for transgenic pollen analysis. In this study, our objective was to determine the accuracy of using flow cytometry technology for transgenic pollen quantification in practical application where transgenic pollen is not frequent. A suspension of non-transgenic tobacco pollen was spiked with a known amount of verified transgenic tobacco pollen synthesizing low or high amounts of green fluorescent protein (GFP). The flow cytometric method detected approximately 75% and 100% of pollen grains synthesizing low and high amounts of GFP, respectively. The method is rapid, as it is able to count 5000 pollen grains per minute-long run. Our data indicate that this flow cytometric method is useful to study gene flow and assessment of transgene containment.

Evaluation of methods for rapid determination of freezing point of aviation fuels

NASA Technical Reports Server (NTRS)

Mathiprakasam, B.

1982-01-01

Methods for identification of the more promising concepts for the development of a portable instrument to rapidly determine the freezing point of aviation fuels are described. The evaluation process consisted of: (1) collection of information on techniques previously used for the determination of the freezing point, (2) screening and selection of these techniques for further evaluation of their suitability in a portable unit for rapid measurement, and (3) an extensive experimental evaluation of the selected techniques and a final selection of the most promising technique. Test apparatuses employing differential thermal analysis and the change in optical transparency during phase change were evaluated and tested. A technique similar to differential thermal analysis using no reference fuel was investigated. In this method, the freezing point was obtained by digitizing the data and locating the point of inflection. Results obtained using this technique compare well with those obtained elsewhere using different techniques. A conceptual design of a portable instrument incorporating this technique is presented.

Assessment of the Short-Term Radiometric Stability between Terra MODIS and Landsat 7 ETM+ Sensors

NASA Technical Reports Server (NTRS)

Choi, Taeyoung; Xiong, Xiaxiong; Chander, G.; Angal, Amit

2009-01-01

The Landsat 7 (L7) Enhanced Thematic Mapper (ETM+) sensor was launched on April 15th, 1999 and has been in operation for over nine years. It has six reflective solar spectral bands located in the visible and shortwave infrared part of the electromagnetic spectrum (0.5 - 2.5 micron) at a spatial resolution of 30 m. The on-board calibrators are used to monitor the on-orbit sensor system changes. The ETM+ performs solar calibrations using on-board Full Aperture Solar Calibrator (FASC) and the Partial Aperture Solar Calibrator (PASC). The Internal Calibrator Lamp (IC) lamps, a blackbody and shutter optics constitute the on-orbit calibration mechanism for ETM+. On 31 May 2003, a malfunction of the scan-line corrector (SLC) mirror assembly resulted in the loss of approximately 22% of the normal scene area. The missing data affects most of the image with scan gaps varying in width from one pixel or less near the centre of the image to 14 pixels along the east and west edges of the image, creating a wedge-shaped pattern. However, the SLC failure has no impacts on the radiometric performance of the valid pixels. On December 18, 1999, the Moderate Resolution Imaging Spectroradiometer (MODIS) Proto-Flight Model (PFM) was launched on-board the NASA's EOS Terra spacecraft. Terra MODIS has 36 spectral bands with wavelengths ranging from 0.41 to 14.5 micron and collects data over a wide field of view angle (+/-55 deg) at three nadir spatial resolutions of 250 m, 500 in 1 km for bands 1 to 2, 3 to 7, and 8 to 36, respectively. It has 20 reflective solar bands (RSB) with spectral wavelengths from 0.41 to 2.1 micron. The RSB radiometric calibration is performed by using on-board solar diffuser (SD), solar diffuser stability monitor (SDSM), space-view (SV), and spectro-radiometric calibration assembly (SRCA). Through the SV port, periodic lunar observations are used to track radiometric response changes at different angles of incidence (AOI) of the scan mirror. As a part of the AM

A rapid detection method for paralytic shellfish poisoning toxins by cell bioassay.

PubMed

Okumura, Masanao; Tsuzuki, Hideaki; Tomita, Ban-Ichi

2005-07-01

We report here a rapid detection method for paralytic shellfish poisoning (PSP) toxins using a cultured neuroblastoma cell line, modified from the bioassay system previously established by Manger et al. [Manger, R.L., Leja, L.S., Lee, S.Y., Hungerford, J.M., Kirkpatrick, M.A., Yasumoto, T., Wekell, M.M., 2003. Detection of paralytic shellfish poison by rapid cell bioassay: antagonism of voltage-gated sodium channel active toxins in vitro. J. AOAC Int. 86 (3), 540-543]. In the present study, we made two major modifications to the previous method. The first is the use of maitotoxin, a marine toxin of ciguatera fish poisoning, which enables the incubation period to be reduced to 6 h when applied to the microplate 15 min prior to the end of the incubation. The second is the use of WST-8, a dehydrogenase detecting water-soluble tetrazolium salt for determining the target cell viability, which permits the omission of a washing step and simplifies the counting process. In addition, we attempted to reduce the required materials as much as possible. Thus, our modified method should be useful for screening the PSP-toxins from shellfish.

Large-scale clinical comparison of the lysis-centrifugation and radiometric systems for blood culture

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

Brannon, P.; Kiehn, T.E.

1985-12-01

The Isolator 10 lysis-centrifugation blood culture system (E. I. du Pont de Nemours and Co., Inc., Wilmington, Del.) was compared with the BACTEC radiometric method (Johnston Laboratories, Inc., Towson, Md.) with 6B and 7D broth media for the recovery of bacteria and yeasts. From 11,000 blood cultures, 1,174 clinically significant organisms were isolated. The Isolator system recovered significantly more total organisms, members of the family Enterobacteriaceae, Staphylococcus spp., and yeasts. The BACTEC system recovered significantly more Pseudomonas spp., Streptococcus spp., and anaerobes. Of the Isolator colony counts, 87% measured less than 11 CFU/ml of blood. Organisms, on an average, weremore » detected the same day from each of the two culture systems. Only 13 of the 975 BACTEC isolates (0.01%) were recovered by subculture of growth-index-negative bottles, and 12 of the 13 were detected in another broth blood culture taken within 24 h. Contaminants were recovered from 4.8% of the Isolator 10 and 2.3% of the BACTEC cultures.« less

Radiometric assay for cytochrome P-450-catalyzed progesterone 16 alpha-hydroxylation and determination of an apparent isotope effect

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

Osawa, Y.; Coon, M.J.

1987-08-01

In the course of studies on the oxygenation of steroids by purified P-450 cytochromes, particularly rabbit liver microsomal cytochrome P-450 form 3b, a rapid and reliable radiometric assay has been devised for progesterone 16 alpha-hydroxylation. In view of the lack of a commercially available, suitably tritiated substrate, (1,2,6,7,16,17-3H)progesterone was treated with alkali to remove the label from potential hydroxylation sites other than the 16 alpha position. The resulting (1,7,16-3H)progesterone was added to a reconstituted enzyme system containing cytochrome P-450 form 3b, NADPH-cytochrome P-450 reductase, and NADPH, and the rate of 16 alpha-hydroxylation was measured by the formation of /sup 3/H/submore » 2/O. This reaction was shown to be linear with respect to time and to the cytochrome P-450 concentration. An apparent tritium isotope effect of 2.1 was observed by comparison of the rates of formation of tritium oxide and 16 alpha-hydroxyprogesterone, and the magnitude of the isotope effect was confirmed by an isotope competition assay in which a mixture of (1,7,16-/sup 3/H)progesterone and (4-14C)progesterone was employed.« less

Rapid method for determination of carbonyl groups in lignin compounds by headspace gas chromatography.

PubMed

Li, Jing; Hu, Hui-Chao; Chai, Xin-Sheng

2015-07-24

The paper reports on a novel method for rapid determination of carbonyl in lignins by headspace gas chromatography (HS-GC). The method involves the quantitative carbonyl reduction for aldehydes in 2min at room temperature or for acetones in 30min at 80°C by sodium borohydride solution in a closed headspace sample vial. After the reaction, the solution was acidified by injecting sulfuric acid solution and the hydrogen released to the headspace was determined by GC using thermal-conductivity detector. The results showed that with the addition of SiO2 powder, the reduction reaction of carbonyl groups can be greatly facilitated. The method has a good measurement precision (RSD<7.74%) and accuracy (relative error <10% compared with a reference method) in the carbonyl quantification. It is suitable to be used for rapid determination of carbonyl content in lignin and related materials. Copyright © 2015 Elsevier B.V. All rights reserved.

A Rapid Method for the Determination of Fucoxanthin in Diatom

PubMed Central

Wang, Li-Juan; Fan, Yong; Parsons, Ronald L.; Hu, Guang-Rong; Zhang, Pei-Yu

2018-01-01

Fucoxanthin is a natural pigment found in microalgae, especially diatoms and Chrysophyta. Recently, it has been shown to have anti-inflammatory, anti-tumor, and anti-obesityactivity in humans. Phaeodactylum tricornutum is a diatom with high economic potential due to its high content of fucoxanthin and eicosapentaenoic acid. In order to improve fucoxanthin production, physical and chemical mutagenesis could be applied to generate mutants. An accurate and rapid method to assess the fucoxanthin content is a prerequisite for a high-throughput screen of mutants. In this work, the content of fucoxanthin in P. tricornutum was determined using spectrophotometry instead of high performance liquid chromatography (HPLC). This spectrophotometric method is easier and faster than liquid chromatography and the standard error was less than 5% when compared to the HPLC results. Also, this method can be applied to other diatoms, with standard errors of 3–14.6%. It provides a high throughput screening method for microalgae strains producing fucoxanthin. PMID:29361768

A rapid method to characterize seabed habitats and associated macro-organisms

USGS Publications Warehouse

Anderson, T.J.; Cochrane, G.R.; Roberts, D.A.; Chezar, H.; Hatcher, G.; ,

2007-01-01

This study presents a method for rapidly collecting, processing, and interrogating real-time abiotic and biotic seabed data to determine seabed habitat classifications. This is done from data collected over a large area of an acoustically derived seabed map, along multidirectional transects, using a towed small camera-sled. The seabed, within the newly designated Point Harris Marine Reserve on the northern coast of San Miguel Island, California, was acoustically imaged using sidescan sonar then ground-truthed using a towed small camera-sled. Seabed characterizations were made from video observations, and were logged to a laptop computer (PC) in real time. To ground-truth the acoustic mosaic, and to characterize abiotic and biotic aspects of the seabed, a three-tiered characterization scheme was employed that described the substratum type, physical structure (i.e., bedform or vertical relief), and the occurrence of benthic macrofauna and flora. A crucial advantage of the method described here, is that preliminary seabed characterizations can be interrogated and mapped over the sidescan mosaic and other seabed information within hours of data collection. This ability to rapidly process seabed data is invaluable to scientists and managers, particularly in modifying concurrent or planning subsequent surveys.

Initial Assessment of a Rapid Method of Calculating CEV Environmental Heating

NASA Technical Reports Server (NTRS)

Pickney, John T.; Milliken, Andrew H.

2010-01-01

An innovative method for rapidly calculating spacecraft environmental absorbed heats in planetary orbit is described. The method employs reading a database of pre-calculated orbital absorbed heats and adjusting those heats for desired orbit parameters. The approach differs from traditional Monte Carlo methods that are orbit based with a planet centered coordinate system. The database is based on a spacecraft centered coordinated system where the range of all possible sun and planet look angles are evaluated. In an example case 37,044 orbit configurations were analyzed for average orbital heats on selected spacecraft surfaces. Calculation time was under 2 minutes while a comparable Monte Carlo evaluation would have taken an estimated 26 hours

Application of ICME Methods for the Development of Rapid Manufacturing Technologies

NASA Astrophysics Data System (ADS)

Maiwald-Immer, T.; Göhler, T.; Fischersworring-Bunk, A.; Körner, C.; Osmanlic, F.; Bauereiß, A.

Rapid manufacturing technologies are lately gaining interest as alternative manufacturing method. Due to the large parameter sets applicable in these manufacturing methods and their impact on achievable material properties and quality, support of the manufacturing process development by the use of simulation is highly attractive. This is especially true for aerospace applications with their high quality demands and controlled scatter in the resulting material properties. The applicable simulation techniques to these manufacturing methods are manifold. The paper will focus on the melt pool simulation for a SLM (selective laser melting) process which was originally developed for EBM (electron beam melting). It will be discussed in the overall context of a multi-scale simulation within a virtual process chain.

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.

[Research on rapid and quantitative detection method for organophosphorus pesticide residue].

PubMed

Sun, Yuan-Xin; Chen, Bing-Tai; Yi, Sen; Sun, Ming

2014-05-01

The methods of physical-chemical inspection is adopted in the traditional pesticide residue detection, which require a lot of pretreatment processes, are time-consuming and complicated. In the present study, the authors take chlorpyrifos applied widely in the present agricultural field as the research object and propose a rapid and quantitative detection method for organophosphorus pesticide residues. At first, according to the chemical characteristics of chlorpyrifos and comprehensive chromogenic effect of several colorimetric reagents and secondary pollution, the pretreatment of the scheme of chromogenic reaction of chlorpyrifos with resorcin in a weak alkaline environment was determined. Secondly, by analyzing Uv-Vis spectrum data of chlorpyrifos samples whose content were between 0. 5 and 400 mg kg-1, it was confirmed that the characteristic information after the color reaction mainly was concentrated among 360 approximately 400 nm. Thirdly, the full spectrum forecasting model was established based on the partial least squares, whose correlation coefficient of calibration was 0. 999 6, correlation coefficient of prediction reached 0. 995 6, standard deviation of calibration (RMSEC) was 2. 814 7 mg kg-1, and standard deviation of verification (RMSEP) was 8. 012 4 mg kg-1. Fourthly, the wavelengths whose center wavelength is 400 nm was extracted as characteristic region to build a forecasting model, whose correlation coefficient of calibration was 0. 999 6, correlation coefficient of prediction reached 0. 999 3, standard deviation of calibration (RMSEC) was 2. 566 7 mg kg-1 , standard deviation of verification (RMSEP) was 4. 886 6 mg kg-1, respectively. At last, by analyzing the near infrared spectrum data of chlorpyrifos samples with contents between 0. 5 and 16 mg kg-1, the authors found that although the characteristics of the chromogenic functional group are not obvious, the change of absorption peaks of resorcin itself in the neighborhood of 5 200 cm

A novel sample preparation method using rapid nonheated saponification method for the determination of cholesterol in emulsified foods.

PubMed

Jeong, In-Seek; Kwak, Byung-Man; Ahn, Jang-Hyuk; Leem, Donggil; Yoon, Taehyung; Yoon, Changyong; Jeong, Jayoung; Park, Jung-Min; Kim, Jin-Man

2012-10-01

In this study, nonheated saponification was employed as a novel, rapid, and easy sample preparation method for the determination of cholesterol in emulsified foods. Cholesterol content was analyzed using gas chromatography with a flame ionization detector (GC-FID). The cholesterol extraction method was optimized for maximum recovery from baby food and infant formula. Under these conditions, the optimum extraction solvent was 10 mL ethyl ether per 1 to 2 g sample, and the saponification solution was 0.2 mL KOH in methanol. The cholesterol content in the products was determined to be within the certified range of certified reference materials (CRMs), NIST SRM 1544 and SRM 1849. The results of the recovery test performed using spiked materials were in the range of 98.24% to 99.45% with an relative standard devitation (RSD) between 0.83% and 1.61%. This method could be used to reduce sample pretreatment time and is expected to provide an accurate determination of cholesterol in emulsified food matrices such as infant formula and baby food. A novel, rapid, and easy sample preparation method using nonheated saponification was developed for cholesterol detection in emulsified foods. Recovery tests of CRMs were satisfactory, and the recoveries of spiked materials were accurate and precise. This method was effective and decreased the time required for analysis by 5-fold compared to the official method. © 2012 Institute of Food Technologists®

In-Situ Cameras for Radiometric Correction of Remotely Sensed Data

NASA Astrophysics Data System (ADS)

Kautz, Jess S.

The atmosphere distorts the spectrum of remotely sensed data, negatively affecting all forms of investigating Earth's surface. To gather reliable data, it is vital that atmospheric corrections are accurate. The current state of the field of atmospheric correction does not account well for the benefits and costs of different correction algorithms. Ground spectral data are required to evaluate these algorithms better. This dissertation explores using cameras as radiometers as a means of gathering ground spectral data. I introduce techniques to implement a camera systems for atmospheric correction using off the shelf parts. To aid the design of future camera systems for radiometric correction, methods for estimating the system error prior to construction, calibration and testing of the resulting camera system are explored. Simulations are used to investigate the relationship between the reflectance accuracy of the camera system and the quality of atmospheric correction. In the design phase, read noise and filter choice are found to be the strongest sources of system error. I explain the calibration methods for the camera system, showing the problems of pixel to angle calibration, and adapting the web camera for scientific work. The camera system is tested in the field to estimate its ability to recover directional reflectance from BRF data. I estimate the error in the system due to the experimental set up, then explore how the system error changes with different cameras, environmental set-ups and inversions. With these experiments, I learn about the importance of the dynamic range of the camera, and the input ranges used for the PROSAIL inversion. Evidence that the camera can perform within the specification set for ELM correction in this dissertation is evaluated. The analysis is concluded by simulating an ELM correction of a scene using various numbers of calibration targets, and levels of system error, to find the number of cameras needed for a full

Characterization of Titan surface scenarios combining Cassini SAR images and radiometric data

NASA Astrophysics Data System (ADS)

Ventura, B.; Notarnicola, C.; Casarano, D.; Janssen, M.; Posa, F.; Cassini RADAR Science Team

2009-04-01

A great amount of data and images was provided by the radar on Cassini probe, thus opening and suggesting new scenarios about Titan's formation and evolution. An important result was the detection, among the peculiar and heterogeneous Titan's surface features, of lakes most likely constituted by liquid hydrocarbons, thus supporting the hypothesis of a methane cycle similar to water cycle on Earth.These areas, which resemble terrestrial lakes, seem to be sprinkled all over the high latitudes surrounding Titan's pole. The abundant methane in Titan's atmosphere combined with the low temperature, 94 K, lead scientists to interpret them as lakes of liquid methane or ethane. In this work, scattering models and a Bayesian inversion algorithm are applied in order to characterize lake and land surfaces. The possibility of combining the SAR data with radiometric ones on both lakes and neighboring land areas is also presented. Radar backscattering from lakes is described in terms of a double layer model, consisting of Bragg or facets scattering for the upper liquid layer and the Integral Equation Model (IEM) model for the lower solid surface. Furthermore, by means of a gravity-capillary wave model (Donelan-Pierson), the wave spectra of liquid hydrocarbons surfaces are introduced as a function of wind speed and direction. Theoretical radar backscattering coefficient values are compared with the experimental ones collected by the radar in order to estimate physical and morphological surface parameters, and to evaluate their compatibility with the expected constituents for Titan surfaces. This electromagnetic analysis is the starting point for a statistical inversion algorithm which allows determining limits on the parameters values, especially on the optical thickness and wind speed of the lakes. The physical surface parameters inferred by using the inversion algorithm are used as input for a forward radiative transfer model calculation to obtain simulated brightness

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.

Interactive Rapid Dose Assessment Model (IRDAM): reactor-accident assessment methods. Vol. 2

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

Poeton, R.W.; Moeller, M.P.; Laughlin, G.J.

1983-05-01

As part of the continuing emphasis on emergency preparedness, the US Nuclear Regulatory Commission (NRC) sponsored the development of a rapid dose assessment system by Pacific Northwest Laboratory (PNL). This system, the Interactive Rapid Dose Assessment Model (IRDAM) is a micro-computer based program for rapidly assessing the radiological impact of accidents at nuclear power plants. This document describes the technical bases for IRDAM including methods, models and assumptions used in calculations. IRDAM calculates whole body (5-cm depth) and infant thyroid doses at six fixed downwind distances between 500 and 20,000 meters. Radionuclides considered primarily consist of noble gases and radioiodines.more » In order to provide a rapid assessment capability consistent with the capacity of the Osborne-1 computer, certain simplifying approximations and assumptions are made. These are described, along with default values (assumptions used in the absence of specific input) in the text of this document. Two companion volumes to this one provide additional information on IRDAM. The user's Guide (NUREG/CR-3012, Volume 1) describes the setup and operation of equipment necessary to run IRDAM. Scenarios for Comparing Dose Assessment Models (NUREG/CR-3012, Volume 3) provides the results of calculations made by IRDAM and other models for specific accident scenarios.« less

Microwave and Millimeter-Wave Radiometric Studies of Temperature, Water Vapor and Clouds

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

Westwater, Edgeworth

2011-05-06

The importance of accurate measurements of column amounts of water vapor and cloud liquid has been well documented by scientists within the Atmospheric Radiation Measurement (ARM) Program. At the North Slope of Alaska (NSA), both microwave radiometers (MWR) and the MWRProfiler (MWRP), been used operationally by ARM for passive retrievals of the quantities: Precipitable Water Vapor (PWV) and Liquid Water Path (LWP). However, it has been convincingly shown that these instruments are inadequate to measure low amounts of PWV and LWP. In the case of water vapor, this is especially important during the Arctic winter, when PWV is frequently lessmore » than 2 mm. For low amounts of LWP (< 50 g/m{sup 2}), the MWR and MWRP retrievals have an accuracy that is also not acceptable. To address some of these needs, in March-April 2004, NOAA and ARM conducted the NSA Arctic Winter Radiometric Experiment - Water Vapor Intensive Operational Period at the ARM NSA/Adjacent Arctic Ocean (NSA/AAO) site. After this experiment, the radiometer group at NOAA moved to the Center for Environmental Technology (CET) of the Department of Electrical and Computer Engineering of the University of Colorado at Boulder. During this 2004 experiment, a total of 220 radiosondes were launched, and radiometric data from 22.235 to 380 GHz were obtained. Primary instruments included the ARM MWR and MWRP, a Global Positioning System (GPS), as well as the CET Ground-based Scanning Radiometer (GSR). We have analyzed data from these instruments to answer several questions of importance to ARM, including: (a) techniques for improved water vapor measurements; (b) improved calibration techniques during cloudy conditions; (c) the spectral response of radiometers to a variety of conditions: clear, liquid, ice, and mixed phase clouds; and (d) forward modeling of microwave and millimeter wave brightness temperatures from 22 to 380 GHz. Many of these results have been published in the open literature. During the third

Compression-based distance (CBD): a simple, rapid, and accurate method for microbiota composition comparison

PubMed Central

2013-01-01

Background Perturbations in intestinal microbiota composition have been associated with a variety of gastrointestinal tract-related diseases. The alleviation of symptoms has been achieved using treatments that alter the gastrointestinal tract microbiota toward that of healthy individuals. Identifying differences in microbiota composition through the use of 16S rRNA gene hypervariable tag sequencing has profound health implications. Current computational methods for comparing microbial communities are usually based on multiple alignments and phylogenetic inference, making them time consuming and requiring exceptional expertise and computational resources. As sequencing data rapidly grows in size, simpler analysis methods are needed to meet the growing computational burdens of microbiota comparisons. Thus, we have developed a simple, rapid, and accurate method, independent of multiple alignments and phylogenetic inference, to support microbiota comparisons. Results We create a metric, called compression-based distance (CBD) for quantifying the degree of similarity between microbial communities. CBD uses the repetitive nature of hypervariable tag datasets and well-established compression algorithms to approximate the total information shared between two datasets. Three published microbiota datasets were used as test cases for CBD as an applicable tool. Our study revealed that CBD recaptured 100% of the statistically significant conclusions reported in the previous studies, while achieving a decrease in computational time required when compared to similar tools without expert user intervention. Conclusion CBD provides a simple, rapid, and accurate method for assessing distances between gastrointestinal tract microbiota 16S hypervariable tag datasets. PMID:23617892

Compression-based distance (CBD): a simple, rapid, and accurate method for microbiota composition comparison.

PubMed

Yang, Fang; Chia, Nicholas; White, Bryan A; Schook, Lawrence B

2013-04-23

Perturbations in intestinal microbiota composition have been associated with a variety of gastrointestinal tract-related diseases. The alleviation of symptoms has been achieved using treatments that alter the gastrointestinal tract microbiota toward that of healthy individuals. Identifying differences in microbiota composition through the use of 16S rRNA gene hypervariable tag sequencing has profound health implications. Current computational methods for comparing microbial communities are usually based on multiple alignments and phylogenetic inference, making them time consuming and requiring exceptional expertise and computational resources. As sequencing data rapidly grows in size, simpler analysis methods are needed to meet the growing computational burdens of microbiota comparisons. Thus, we have developed a simple, rapid, and accurate method, independent of multiple alignments and phylogenetic inference, to support microbiota comparisons. We create a metric, called compression-based distance (CBD) for quantifying the degree of similarity between microbial communities. CBD uses the repetitive nature of hypervariable tag datasets and well-established compression algorithms to approximate the total information shared between two datasets. Three published microbiota datasets were used as test cases for CBD as an applicable tool. Our study revealed that CBD recaptured 100% of the statistically significant conclusions reported in the previous studies, while achieving a decrease in computational time required when compared to similar tools without expert user intervention. CBD provides a simple, rapid, and accurate method for assessing distances between gastrointestinal tract microbiota 16S hypervariable tag datasets.

Determination of precipitation profiles from airborne passive microwave radiometric measurements

NASA Technical Reports Server (NTRS)

Kummerow, Christian; Hakkarinen, Ida M.; Pierce, Harold F.; Weinman, James A.

1991-01-01

This study presents the first quantitative retrievals of vertical profiles of precipitation derived from multispectral passive microwave radiometry. Measurements of microwave brightness temperature (Tb) obtained by a NASA high-altitude research aircraft are related to profiles of rainfall rate through a multichannel piecewise-linear statistical regression procedure. Statistics for Tb are obtained from a set of cloud radiative models representing a wide variety of convective, stratiform, and anvil structures. The retrieval scheme itself determines which cloud model best fits the observed meteorological conditions. Retrieved rainfall rate profiles are converted to equivalent radar reflectivity for comparison with observed reflectivities from a ground-based research radar. Results for two case studies, a stratiform rain situation and an intense convective thunderstorm, show that the radiometrically derived profiles capture the major features of the observed vertical structure of hydrometer density.

Radiometric calibration and SNR calculation of a SWIR imaging telescope

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

Yilmaz, Ozgur; Turk, Fethi; Selimoglu, Ozgur

2012-09-06

Radiometric calibration of an imaging telescope is usually made using a uniform illumination sphere in a laboratory. In this study, we used the open-sky images taken during bright day conditions to calibrate our telescope. We found a dark signal offset value and a linear response coefficient value for each pixel by using three different algorithms. Then we applied these coefficients to the taken images, and considerably lowered the image non-uniformity. Calibration can be repeated during the operation of telescope with an object that has better uniformity than open-sky. Also SNR (Signal to Noise Ratio) of each pixel was calculated frommore » the open-sky images using the temporal mean and standard deviations. It is found that SNR is greater than 80 for all pixels even at low light levels.« less

Reverse transcription strand invasion based amplification (RT-SIBA): a method for rapid detection of influenza A and B.

PubMed

Eboigbodin, Kevin; Filén, Sanna; Ojalehto, Tuomas; Brummer, Mirko; Elf, Sonja; Pousi, Kirsi; Hoser, Mark

2016-06-01

Rapid and accurate diagnosis of influenza viruses plays an important role in infection control, as well as in preventing the misuse of antibiotics. Isothermal nucleic acid amplification methods offer significant advantages over the polymerase chain reaction (PCR), since they are more rapid and do not require the sophisticated instruments needed for thermal cycling. We previously described a novel isothermal nucleic acid amplification method, 'Strand Invasion Based Amplification' (SIBA®), with high analytical sensitivity and specificity, for the detection of DNA. In this study, we describe the development of a variant of the SIBA method, namely, reverse transcription SIBA (RT-SIBA), for the rapid detection of viral RNA targets. The RT-SIBA method includes a reverse transcriptase enzyme that allows one-step reverse transcription of RNA to complementary DNA (cDNA) and simultaneous amplification and detection of the cDNA by SIBA under isothermal reaction conditions. The RT-SIBA method was found to be more sensitive than PCR for the detection of influenza A and B and could detect 100 copies of influenza RNA within 15 min. The development of RT-SIBA will enable rapid and accurate diagnosis of viral RNA targets within point-of-care or central laboratory settings.

Rapid determination of methylmercury in fish and shellfish: method development

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

Hight, S.C.; Corcoran, M.T.

The AOAC official first action method for methylmercury in fish and shellfish was modified to provide more rapid determination. Methylmercury is isolated from homogenized, acetone-washed tissue by addition of HCl and extraction by toluene of the methylmercuric chloride produced. The extract is analyzed by electron capture gas chromatography (GC) on 5% DEGS-PS treated with mercuric chloride solution. The quantitation limit of the method is 0.25 ..mu..g Hg/g. Swordfish, shark, tuna, shrimp, clams, oysters, and NBS Research Material-50 (tuna) were analyzed for methylmercury by the AOAC official first action method. All products also were analyzed by the modified method and themore » AOAC official method for total Hg. In addition, selected extracts obtained with the modified method were analyzed by GC with Hg-selective, microwave-induced helium plasma detection. There was no significant different between the results for the various methods. Essentially all the Hg present (determined as total Hg) was in the organic form. Coefficients of variation from analyses by the modified method ranged from 1 to 7% for fish and shellfish containing methylmercury at levels of 0.50-2.30 ..mu..g Hg/g. The overall average recovery was 100.5%.« less

A method of rapidly evaluating image quality of NED optical system

NASA Astrophysics Data System (ADS)

Sun, Qi; Qiu, Chuankai; Yang, Huan

2014-11-01

In recent years, with the development of technology of micro-display, advanced optics and the software and hardware, near-to-eye display ( NED) optical system will have a wide range of potential applications in the fields of amusement and virtual reality. However, research on the evaluating image quality of this kind optical system is comparatively lagging behind. Although now there are some methods and equipment for evaluation, they can't be applied in commercial production because of their complex operation and inaccuracy. In this paper, an academic method is proposed and a Rapid Evaluation System (RES) is designed to evaluate the image of optical system rapidly and exactly. Firstly, a set of parameters that eyes are sensitive to and also express the quality of system should be extracted and quantized to be criterion, so the evaluation standards can be established. Then, some parameters can be detected by RES consisted of micro-display, CCD camera and computer and so on. By process of scaling, the measuring results of the RES are exact and creditable, relationship between object measurement, subjective evaluation and the RES will be established. After that, image quality of optical system can be evaluated just by detecting parameters of that. The RES is simple and the results of evaluation are exact and keeping with human vision. So the method can be used not only for optimizing design of optical system, but also for evaluation in commercial production.

The RAPID technique: a new method for evaluating downstream effects of forest practices on riparian zones.

Treesearch

G. Grant

1988-01-01

The RAPID (riparian aerial photographic inventory of disturbance) technique is a method for using measurements made on aerial photographs of patterns of riparian canopy disturbance to evaluate changes in channel conditions through time and to link such changes with their possible upstream causes. The RAPID technique provides resource specialists and managers with a...

Reintroducing radiometric surface temperature into the Penman-Monteith formulation

NASA Astrophysics Data System (ADS)

Mallick, Kaniska; Boegh, Eva; Trebs, Ivonne; Alfieri, Joseph G.; Kustas, William P.; Prueger, John H.; Niyogi, Dev; Das, Narendra; Drewry, Darren T.; Hoffmann, Lucien; Jarvis, Andrew J.

2015-08-01

Here we demonstrate a novel method to physically integrate radiometric surface temperature (TR) into the Penman-Monteith (PM) formulation for estimating the terrestrial sensible and latent heat fluxes (H and λE) in the framework of a modified Surface Temperature Initiated Closure (STIC). It combines TR data with standard energy balance closure models for deriving a hybrid scheme that does not require parameterization of the surface (or stomatal) and aerodynamic conductances (gS and gB). STIC is formed by the simultaneous solution of four state equations and it uses TR as an additional data source for retrieving the "near surface" moisture availability (M) and the Priestley-Taylor coefficient (α). The performance of STIC is tested using high-temporal resolution TR observations collected from different international surface energy flux experiments in conjunction with corresponding net radiation (RN), ground heat flux (G), air temperature (TA), and relative humidity (RH) measurements. A comparison of the STIC outputs with the eddy covariance measurements of λE and H revealed RMSDs of 7-16% and 40-74% in half-hourly λE and H estimates. These statistics were 5-13% and 10-44% in daily λE and H. The errors and uncertainties in both surface fluxes are comparable to the models that typically use land surface parameterizations for determining the unobserved components (gS and gB) of the surface energy balance models. However, the scheme is simpler, has the capabilities for generating spatially explicit surface energy fluxes and independent of submodels for boundary layer developments. This article was corrected on 27 AUG 2015. See the end of the full text for details.

Use of refractometry and colorimetry as field methods to rapidly assess antimalarial drug quality.

PubMed

Green, Michael D; Nettey, Henry; Villalva Rojas, Ofelia; Pamanivong, Chansapha; Khounsaknalath, Lamphet; Grande Ortiz, Miguel; Newton, Paul N; Fernández, Facundo M; Vongsack, Latsamy; Manolin, Ot

2007-01-04

The proliferation of counterfeit and poor-quality drugs is a major public health problem; especially in developing countries lacking adequate resources to effectively monitor their prevalence. Simple and affordable field methods provide a practical means of rapidly monitoring drug quality in circumstances where more advanced techniques are not available. Therefore, we have evaluated refractometry, colorimetry and a technique combining both processes as simple and accurate field assays to rapidly test the quality of the commonly available antimalarial drugs; artesunate, chloroquine, quinine, and sulfadoxine. Method bias, sensitivity, specificity and accuracy relative to high-performance liquid chromatographic (HPLC) analysis of drugs collected in the Lao PDR were assessed for each technique. The HPLC method for each drug was evaluated in terms of assay variability and accuracy. The accuracy of the combined method ranged from 0.96 to 1.00 for artesunate tablets, chloroquine injectables, quinine capsules, and sulfadoxine tablets while the accuracy was 0.78 for enterically coated chloroquine tablets. These techniques provide a generally accurate, yet simple and affordable means to assess drug quality in resource-poor settings.

A resorbable and rapid method for maxillomandibular fixation in pediatric mandible fractures.

PubMed

Eppley, B L

2000-05-01

Maxillomandibular immobilization in pediatric mandible fractures is accomplished through a resorbable screw placed into the zygomatic body to which is attached a large, monofilament, circummandibular suture. Although the screw must be placed intraoperatively, this method of jaw immobilization is rapid, secure, does not damage the teeth, and can be removed in the office in the older child.

Method for rapidly determining a pulp kappa number using spectrophotometry

DOEpatents

Chai, Xin-Sheng; Zhu, Jun Yong

2002-01-01

A system and method for rapidly determining the pulp kappa number through direct measurement of the potassium permanganate concentration in a pulp-permanganate solution using spectrophotometry. Specifically, the present invention uses strong acidification to carry out the pulp-permanganate oxidation reaction in the pulp-permanganate solution to prevent the precipitation of manganese dioxide (MnO.sub.2). Consequently, spectral interference from the precipitated MnO.sub.2 is eliminated and the oxidation reaction becomes dominant. The spectral intensity of the oxidation reaction is then analyzed to determine the pulp kappa number.

Absolute Radiometric Calibration of Narrow-Swath Imaging Sensors with Reference to Non-Coincident Wide-Swath Sensors

NASA Technical Reports Server (NTRS)

McCorkel, Joel; Thome, Kurtis; Lockwood, Ronald

2012-01-01

An inter-calibration method is developed to provide absolute radiometric calibration of narrow-swath imaging sensors with reference to non-coincident wide-swath sensors. The method predicts at-sensor radiance using non-coincident imagery from the reference sensor and knowledge of spectral reflectance of the test site. The imagery of the reference sensor is restricted to acquisitions that provide similar view and solar illumination geometry to reduce uncertainties due to directional reflectance effects. Spectral reflectance of the test site is found with a simple iterative radiative transfer method using radiance values of a well-understood wide-swath sensor and spectral shape information based on historical ground-based measurements. At-sensor radiance is calculated for the narrow-swath sensor using this spectral reflectance and atmospheric parameters that are also based on historical in situ measurements. Results of the inter-calibration method show agreement on the 2 5 percent level in most spectral regions with the vicarious calibration technique relying on coincident ground-based measurements referred to as the reflectance-based approach. While the variability of the inter-calibration method based on non-coincident image pairs is significantly larger, results are consistent with techniques relying on in situ measurements. The method is also insensitive to spectral differences between the sensors by transferring to surface spectral reflectance prior to prediction of at-sensor radiance. The utility of this inter-calibration method is made clear by its flexibility to utilize image pairings with acquisition dates differing in excess of 30 days allowing frequent absolute calibration comparisons between wide- and narrow-swath sensors.

Validated flow-injection method for rapid aluminium determination in anti-perspirants.

PubMed

López-Gonzálvez, A; Ruiz, M A; Barbas, C

2008-09-29

A flow-injection (FI) method for the rapid determination of aluminium in anti-perspirants has been developed. The method is based on the spectrophotometric detection at 535nm of the complex formed between Al ions and the chromogenic reagent eriochrome cyanine R. Both the batch and FI methods were validated by checking the parameters included in the ISO-3543-1 regulation. Variables involved in the FI method were optimized by using appropriate statistical tools. The method does not exhibit interference from other substances present in anti-perspirants and it shows a high precision with a R.S.D. value (n=6) of 0.9%. Moreover, the accuracy of the method was evaluated by comparison with a back complexometric titration method, which is currently used for routine analysis in pharmaceutical laboratories. The Student's t-test showed that the results obtained by both methods were not significantly different for a significance level of 95%. A response time of 12s and a sample analysis time, by performing triplicate injections, of 60s were achieved. The analytical figures of merit make the method highly appropriate to substitute the time-consuming complexometric method for this kind of analysis.

Signature modelling and radiometric rendering equations in infrared scene simulation systems

NASA Astrophysics Data System (ADS)

Willers, Cornelius J.; Willers, Maria S.; Lapierre, Fabian

2011-11-01

The development and optimisation of modern infrared systems necessitates the use of simulation systems to create radiometrically realistic representations (e.g. images) of infrared scenes. Such simulation systems are used in signature prediction, the development of surveillance and missile sensors, signal/image processing algorithm development and aircraft self-protection countermeasure system development and evaluation. Even the most cursory investigation reveals a multitude of factors affecting the infrared signatures of realworld objects. Factors such as spectral emissivity, spatial/volumetric radiance distribution, specular reflection, reflected direct sunlight, reflected ambient light, atmospheric degradation and more, all affect the presentation of an object's instantaneous signature. The signature is furthermore dynamically varying as a result of internal and external influences on the object, resulting from the heat balance comprising insolation, internal heat sources, aerodynamic heating (airborne objects), conduction, convection and radiation. In order to accurately render the object's signature in a computer simulation, the rendering equations must therefore account for all the elements of the signature. In this overview paper, the signature models, rendering equations and application frameworks of three infrared simulation systems are reviewed and compared. The paper first considers the problem of infrared scene simulation in a framework for simulation validation. This approach provides concise definitions and a convenient context for considering signature models and subsequent computer implementation. The primary radiometric requirements for an infrared scene simulator are presented next. The signature models and rendering equations implemented in OSMOSIS (Belgian Royal Military Academy), DIRSIG (Rochester Institute of Technology) and OSSIM (CSIR & Denel Dynamics) are reviewed. In spite of these three simulation systems' different application focus

A RAPID Method for Blood Processing to Increase the Yield of Plasma Peptide Levels in Human Blood.

PubMed

Teuffel, Pauline; Goebel-Stengel, Miriam; Hofmann, Tobias; Prinz, Philip; Scharner, Sophie; Körner, Jan L; Grötzinger, Carsten; Rose, Matthias; Klapp, Burghard F; Stengel, Andreas

2016-04-28

Research in the field of food intake regulation is gaining importance. This often includes the measurement of peptides regulating food intake. For the correct determination of a peptide's concentration, it should be stable during blood processing. However, this is not the case for several peptides which are quickly degraded by endogenous peptidases. Recently, we developed a blood processing method employing Reduced temperatures, Acidification, Protease inhibition, Isotopic exogenous controls and Dilution (RAPID) for the use in rats. Here, we have established this technique for the use in humans and investigated recovery, molecular form and circulating concentration of food intake regulatory hormones. The RAPID method significantly improved the recovery for (125)I-labeled somatostatin-28 (+39%), glucagon-like peptide-1 (+35%), acyl ghrelin and glucagon (+32%), insulin and kisspeptin (+29%), nesfatin-1 (+28%), leptin (+21%) and peptide YY3-36 (+19%) compared to standard processing (EDTA blood on ice, p <0.001). High performance liquid chromatography showed the elution of endogenous acyl ghrelin at the expected position after RAPID processing, while after standard processing 62% of acyl ghrelin were degraded resulting in an earlier peak likely representing desacyl ghrelin. After RAPID processing the acyl/desacyl ghrelin ratio in blood of normal weight subjects was 1:3 compared to 1:23 following standard processing (p = 0.03). Also endogenous kisspeptin levels were higher after RAPID compared to standard processing (+99%, p = 0.02). The RAPID blood processing method can be used in humans, yields higher peptide levels and allows for assessment of the correct molecular form.

Method for rapid base sequencing in DNA and RNA

DOEpatents

Jett, J.H.; Keller, R.A.; Martin, J.C.; Moyzis, R.K.; Ratliff, R.L.; Shera, E.B.; Stewart, C.C.

1987-10-07

A method is provided for the rapid base sequencing of DNA or RNA fragments wherein a single fragment of DNA or RNA is provided with identifiable bases and suspended in a moving flow stream. An exonuclease sequentially cleaves individual bases from the end of the suspended fragment. The moving flow stream maintains the cleaved bases in an orderly train for subsequent detection and identification. In a particular embodiment, individual bases forming the DNA or RNA fragments are individually tagged with a characteristic fluorescent dye. The train of bases is then excited to fluorescence with an output spectrum characteristic of the individual bases. Accordingly, the base sequence of the original DNA or RNA fragment can be reconstructed. 2 figs.

Method for rapid base sequencing in DNA and RNA

DOEpatents

Jett, J.H.; Keller, R.A.; Martin, J.C.; Moyzis, R.K.; Ratliff, R.L.; Shera, E.B.; Stewart, C.C.

1990-10-09

A method is provided for the rapid base sequencing of DNA or RNA fragments wherein a single fragment of DNA or RNA is provided with identifiable bases and suspended in a moving flow stream. An exonuclease sequentially cleaves individual bases from the end of the suspended fragment. The moving flow stream maintains the cleaved bases in an orderly train for subsequent detection and identification. In a particular embodiment, individual bases forming the DNA or RNA fragments are individually tagged with a characteristic fluorescent dye. The train of bases is then excited to fluorescence with an output spectrum characteristic of the individual bases. Accordingly, the base sequence of the original DNA or RNA fragment can be reconstructed. 2 figs.

Method for rapid base sequencing in DNA and RNA

DOEpatents

Jett, James H.; Keller, Richard A.; Martin, John C.; Moyzis, Robert K.; Ratliff, Robert L.; Shera, E. Brooks; Stewart, Carleton C.

1990-01-01

A method is provided for the rapid base sequencing of DNA or RNA fragments wherein a single fragment of DNA or RNA is provided with identifiable bases and suspended in a moving flow stream. An exonuclease sequentially cleaves individual bases from the end of the suspended fragment. The moving flow stream maintains the cleaved bases in an orderly train for subsequent detection and identification. In a particular embodiment, individual bases forming the DNA or RNA fragments are individually tagged with a characteristic fluorescent dye. The train of bases is then excited to fluorescence with an output spectrum characteristic of the individual bases. Accordingly, the base sequence of the original DNA or RNA fragment can be reconstructed.

Evaluating Radiometric Sensitivity of LandSat 8 Over Coastal-Inland Waters

NASA Technical Reports Server (NTRS)

Pahlevan, Nima; Wei, Jian-Wei; Shaaf, Crystal B.; Schott, John R.

2014-01-01

The operational Land Imager (OLI) aboard Landsat 8 was launched in February 2013 to continue the Landsat's mission of monitoring earth resources at relatively high spatial resolution. Compared to Landsat heritage sensors, OLI has an additional 443-nm band (termed coastal/aerosol (CA) band), which extends its potential for mapping/monitoring water quality in coastal/inland waters. In addition, OLI's pushbroom design allows for longer integration time and, as a result, higher signal-to-noise ratio (SNR). Using a series of radiative transfer simulations, we provide insights into the radiometric sensitivity of OLI when studying coastal/inland waters. This will address how the changes in water constituents manifest at top-of-atmosphere (TOA) and whether the changes are resolvable at TOA (focal plane) relative to OLI's overall noise.

Radiometric calibration of an airborne multispectral scanner. [of Thematic Mapper Simulator

NASA Technical Reports Server (NTRS)

Markham, Brian L.; Ahmad, Suraiya P.; Jackson, Ray D.; Moran, M. S.; Biggar, Stuart F.; Gellman, David I.; Slater, Philip N.

1991-01-01

The absolute radiometric calibration of the NS001 Thematic Mapper Simulator reflective channels was examined based on laboratory tests and in-flight comparisons to ground measurements. The NS001 data are calibrated in-flight by reference to the NS001 internal integrating sphere source. This source's power supply or monitoring circuitry exhibited greater instability in-flight during 1988-1989 than in the laboratory. Extrapolating laboratory behavior to in-flight data resulted in 7-20 percent radiance errors relative to ground measurements and atmospheric modeling. Assuming constancy in the source's output between laboraotry and in-flight resulted in generally smaller errors. Upgrades to the source's power supply and monitoring circuitry in 1990 improved its in-flight stability, though in-flight ground reflectance based calibration tests have not yet been performed.

Radiometric, geometric, and image quality assessment of ALOS AVNIR-2 and PRISM sensors

USGS Publications Warehouse

Saunier, S.; Goryl, P.; Chander, G.; Santer, R.; Bouvet, M.; Collet, B.; Mambimba, A.; Kocaman, Aksakal S.

2010-01-01

The Advanced Land Observing Satellite (ALOS) was launched on January 24, 2006, by a Japan Aerospace Exploration Agency (JAXA) H-IIA launcher. It carries three remote-sensing sensors: 1) the Advanced Visible and Near-Infrared Radiometer type 2 (AVNIR-2); 2) the Panchromatic Remote-Sensing Instrument for Stereo Mapping (PRISM); and 3) the Phased-Array type L-band Synthetic Aperture Radar (PALSAR). Within the framework of ALOS Data European Node, as part of the European Space Agency (ESA), the European Space Research Institute worked alongside JAXA to provide contributions to the ALOS commissioning phase plan. This paper summarizes the strategy that was adopted by ESA to define and implement a data verification plan for missions operated by external agencies; these missions are classified by the ESA as third-party missions. The ESA was supported in the design and execution of this plan by GAEL Consultant. The verification of ALOS optical data from PRISM and AVNIR-2 sensors was initiated 4 months after satellite launch, and a team of principal investigators assembled to provide technical expertise. This paper includes a description of the verification plan and summarizes the methodologies that were used for radiometric, geometric, and image quality assessment. The successful completion of the commissioning phase has led to the sensors being declared fit for operations. The consolidated measurements indicate that the radiometric calibration of the AVNIR-2 sensor is stable and agrees with the Landsat-7 Enhanced Thematic Mapper Plus and the Envisat MEdium-Resolution Imaging Spectrometer calibration. The geometrical accuracy of PRISM and AVNIR-2 products improved significantly and remains under control. The PRISM modulation transfer function is monitored for improved characterization.

Radiometric calibration of SeaWiFS in the near infrared

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

Martiny, Nadege; Frouin, Robert; Santer, Richard

2005-12-20

The radiometric calibration of the Sea-Viewing Wide-Field-of-View Sensor (SeaWiFS) in the near infrared (band 8, centered on 865 nm) is evaluated by use of ground-based radiometer measurements of solar extinction and sky radiance in the Sun's principal plane at two sites, one located 13 km off Venice, Italy, and the other on the west coast of Lanai Island, Hawaii. The aerosol optical thickness determined from solar extinction is used in an iterative scheme to retrieve the pseudo aerosol phase function, i.e., the product of single-scattering albedo and phase function, in which sky radiance is corrected for multiple scattering effects. Nomore » assumption about the aerosol model is required. The aerosol parameters are the inputs into a radiation-transfer code used to compute the SeaWiFS radiance. The calibration method has a theoretical inaccuracy of plus or minus 2.0-3.6%, depending on the solar zenith angle and the SeaWiFS geometry. The major source of error is in the calibration of the ground-based radiometer operated in radiance mode, assumed to be accurate to {+-}2%. The establishment of strict criteria for atmospheric stability, angular geometry, and surface conditions resulted in selection of only 26 days for the analysis during 1999-2000 (Venice site) and 1998-2001 (Lanai site). For these days the measured level-1B radiance from the SeaWiFS Project Office was generally lower than the corresponding simulated radiance in band 8 by 7.0% on average, {+-}2.8%.« less

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

Comparison of a rapid micromedia method to cystine trypticase agar (CTA) and fluorescent methods for the identification of pathogenic Neisseria.

PubMed

Brake, S R; Marsik, F J; Rein, M R

1982-01-01

A four-hour micromedia method which detects enzymes formed by bacteria for the degradion of carbohydrates was compared to the utilization of carbohydrates was compared to the utilization of carbohydrates in cystine tyrpticase agar (CTA) for the identification of Neisseria gonorrhoeae and Neisseria meningitidis. This rapid micromedia method (RMM) correlated 100% with the utilization of carbohydrates in CTA. Identification of N. gonorrhoeae by RMM was compared to the identification achieved by a commercially available coagglutination method and a fluorescent antibody (FA) technique. Of 144 isolates identified as N. gonorrhoeae by RMM, 122 (84.7%) were identified by coagglutination and 141 (97.9%) were identified by FA as N. gonorrhoeae. Five (13%) of 40 isolates identified as N. meningitidis by RMM were identified as N. gonorrhoeae by coagglutination while eleven (28%) were identified as N. gonorrhoeae by the FA technique. One (14%) and four (57%) of seven isolates identified as Neisseria species were identified as N. gonorrhoeae by coagglutination and the FA technique respectively. The rapid micromedia method was found to be a quick, sensitive, specific and economic way of identifying N. gonorrhoeae and N. meningitidis.

Comparing rapid methods for detecting Listeria in seafood and environmental samples using the most probably number (MPN) technique.

PubMed

Cruz, Cristina D; Win, Jessicah K; Chantarachoti, Jiraporn; Mutukumira, Anthony N; Fletcher, Graham C

2012-02-15

The standard Bacteriological Analytical Manual (BAM) protocol for detecting Listeria in food and on environmental surfaces takes about 96 h. Some studies indicate that rapid methods, which produce results within 48 h, may be as sensitive and accurate as the culture protocol. As they only give presence/absence results, it can be difficult to compare the accuracy of results generated. We used the Most Probable Number (MPN) technique to evaluate the performance and detection limits of six rapid kits for detecting Listeria in seafood and on an environmental surface compared with the standard protocol. Three seafood products and an environmental surface were inoculated with similar known cell concentrations of Listeria and analyzed according to the manufacturers' instructions. The MPN was estimated using the MPN-BAM spreadsheet. For the seafood products no differences were observed among the rapid kits and efficiency was similar to the BAM method. On the environmental surface the BAM protocol had a higher recovery rate (sensitivity) than any of the rapid kits tested. Clearview™, Reveal®, TECRA® and VIDAS® LDUO detected the cells but only at high concentrations (>10(2) CFU/10 cm(2)). Two kits (VIP™ and Petrifilm™) failed to detect 10(4) CFU/10 cm(2). The MPN method was a useful tool for comparing the results generated by these presence/absence test kits. There remains a need to develop a rapid and sensitive method for detecting Listeria in environmental samples that performs as well as the BAM protocol, since none of the rapid tests used in this study achieved a satisfactory result. Copyright © 2011 Elsevier B.V. All rights reserved.

Subsurface Exploration Methods for Soft Ground Rapid Transit Tunnels : Volume 2. Appendixes A-F.

DOT National Transportation Integrated Search

1976-04-01

This study assesses subsurface exploration methods with respect to their ability to provide adequate data for the construction of rapid transit, soft-ground bored and cut-and-cover tunnels. Geophysical and other exploration tools not now widely used ...

Recent advances in rapid pathogen detection method based on biosensors.

PubMed

Chen, Ying; Wang, Zhenzhen; Liu, Yingxun; Wang, Xin; Li, Ying; Ma, Ping; Gu, Bing; Li, Hongchun

2018-06-01

As strain variation and drug resistance become more pervasive, the prevention and control of infection have been a serious problem in recent years. The detection of pathogen is one of the most important parts of the process of diagnosis. Having a series of advantages, such as rapid response, high sensitivity, ease of use, and low cost, biosensors have received much attention and been studied deeply. Moreover, relying on its characteristics of small size, real time, and multiple analyses, biosensors have developed rapidly and used widely and are expected to be applied for microbiological detection in order to meet higher accuracy required by clinical diagnosis. The main goal of this contribution is not to simply collect and list all papers related to pathogen detection based on biosensors published recently, but to discuss critically the development and application of many kinds of biosensors such as electrochemical (amperometric, impedimetric, potentiometric, and conductometric), optical (fluorescent, fibre optic and surface plasmon resonance), and piezoelectric (quartz crystal microbalances and atomic force microscopy) biosensors in pathogen detection as well as the comparisons with the existing clinical detection methods (traditional culture, enzyme-linked immunosorbent assay, polymerase chain reaction, and mass spectrometry).

Landsat-8 TIRS thermal radiometric calibration status

USGS Publications Warehouse

Barsi, Julia A.; Markham, Brian L.; Montanaro, Matthew; Gerace, Aaron; Hook, Simon; Schott, John R.; Raqueno, Nina G.; Morfitt, Ron

2017-01-01

The Thermal Infrared Sensor (TIRS) instrument is the thermal-band imager on the Landsat-8 platform. The initial onorbit calibration estimates of the two TIRS spectral bands indicated large average radiometric calibration errors, -0.29 and -0.51 W/m2 sr μm or -2.1K and -4.4K at 300K in Bands 10 and 11, respectively, as well as high variability in the errors, 0.87K and 1.67K (1-σ), respectively. The average error was corrected in operational processing in January 2014, though, this adjustment did not improve the variability. The source of the variability was determined to be stray light from far outside the field of view of the telescope. An algorithm for modeling the stray light effect was developed and implemented in the Landsat-8 processing system in February 2017. The new process has improved the overall calibration of the two TIRS bands, reducing the residual variability in the calibration from 0.87K to 0.51K at 300K for Band 10 and from 1.67K to 0.84K at 300K for Band 11. There are residual average lifetime bias errors in each band: 0.04 W/m2 sr μm (0.30K) and -0.04 W/m2 sr μm (-0.29K), for Bands 10 and 11, respectively.

JPSS-1 VIIRS Pre-Launch Radiometric Performance

NASA Technical Reports Server (NTRS)

Oudrari, Hassan; Mcintire, Jeffrey; Xiong, Xiaoxiong; Butler, James; Ji, Qiang; Schwarting, Tom; Zeng, Jinan

2015-01-01

The first Joint Polar Satellite System (JPSS-1 or J1) mission is scheduled to launch in January 2017, and will be very similar to the Suomi-National Polar-orbiting Partnership (SNPP) mission. The Visible Infrared Imaging Radiometer Suite (VIIRS) on board the J1 spacecraft completed its sensor level performance testing in December 2014. VIIRS instrument is expected to provide valuable information about the Earth environment and properties on a daily basis, using a wide-swath (3,040 km) cross-track scanning radiometer. The design covers the wavelength spectrum from reflective to long-wave infrared through 22 spectral bands, from 0.412 m to 12.01 m, and has spatial resolutions of 370 m and 740 m at nadir for imaging and moderate bands, respectively. This paper will provide an overview of pre-launch J1 VIIRS performance testing and methodologies, describing the at-launch baseline radiometric performance as well as the metrics needed to calibrate the instrument once on orbit. Key sensor performance metrics include the sensor signal to noise ratios (SNRs), dynamic range, reflective and emissive bands calibration performance, polarization sensitivity, bands spectral performance, response-vs-scan (RVS), near field response, and stray light rejection. A set of performance metrics generated during the pre-launch testing program will be compared to the sensor requirements and to SNPP VIIRS pre-launch performance.

Rapid and efficient method to extract metagenomic DNA from estuarine sediments.

PubMed

Shamim, Kashif; Sharma, Jaya; Dubey, Santosh Kumar

2017-07-01

Metagenomic DNA from sediments of selective estuaries of Goa, India was extracted using a simple, fast, efficient and environment friendly method. The recovery of pure metagenomic DNA from our method was significantly high as compared to other well-known methods since the concentration of recovered metagenomic DNA ranged from 1185.1 to 4579.7 µg/g of sediment. The purity of metagenomic DNA was also considerably high as the ratio of absorbance at 260 and 280 nm ranged from 1.88 to 1.94. Therefore, the recovered metagenomic DNA was directly used to perform various molecular biology experiments viz. restriction digestion, PCR amplification, cloning and metagenomic library construction. This clearly proved that our protocol for metagenomic DNA extraction using silica gel efficiently removed the contaminants and prevented shearing of the metagenomic DNA. Thus, this modified method can be used to recover pure metagenomic DNA from various estuarine sediments in a rapid, efficient and eco-friendly manner.

Landsat-8 Operational Land Imager On-Orbit Radiometric Calibration

NASA Technical Reports Server (NTRS)

Markham, Brian L.; Barsi, Julia A.

2017-01-01

The Operational Land Imager (OLI), the VIS/NIR/SWIR sensor on the Landsat-8 has been successfully acquiring Earth Imagery for more than four years. The OLI incorporates two on-board radiometric calibration systems, one diffuser based and one lamp based, each with multiple sources. For each system one source is treated as primary and used frequently and the other source(s) are used less frequently to assist in tracking any degradation in the primary sources. In addition, via a spacecraft maneuver, the OLI instrument views the moon once a lunar cycle (approx. 29 days). The integrated lunar irradiances from these acquisitions are compared to the output of a lunar irradiance model. The results from all these techniques, combined with cross calibrations with other sensors and ground based vicarious measurements are used to monitor the OLI's stability and correct for any changes observed. To date, the various techniques have other detected significant changes in the shortest wavelength OLI band centered at 443 nm and these are currently being adjusted in the operational processing.

Update of S-NPP VIIRS Thermal Emissive Bands Radiometric Calibration Stability Monitoring Using the Moon

NASA Technical Reports Server (NTRS)

Wang, Zhipeng; Xiong, Xiaoxiong; Li, Yonghong

2016-01-01

The Suomi-NPP VIIRS thermal emissive bands (TEB) are radiometrically calibrated on-orbit with reference to an onboard blackbody (BB) regularly operated at approximately 292.5 K. The calibration stability at other temperature ranges can be evaluated based on the observations of remote targets with stable thermal properties, such as the Moon. VIIRS has scheduled viewings of the Moon on a nearly monthly basis at a phase angle of nearly -51 degrees. In this study, the brightness temperatures (BT) of the lunar surface retrieved using the detector gain coefficients calibrated with the BB are trended to monitor the calibration stability of VIIRS TEB. Since the Lunar surface temperatures are spatially non-uniform and vary greatly with the photometric geometry, the BT trending must be based on the same regions of the Moon under the same solar illumination condition. Also, the TEB lunar images are always partially saturated because the highest lunar surface temperatures are beyond the dynamic range of all VIIRS TEB detectors. Therefore, a temporally invariant dynamic mask is designed to clip a fraction of the lunar images corresponding to the regions of the Moon that may saturate the detector at any lunar event. The BT of the remaining hottest pixels are then trended. Results show that, since the launch of VIIRS to mid-2016, the radiometric calibration of all TEB detectors has been stable within 0.4 K at the BT range of as high as 350 K.

A Rapid Method to Achieve Aero-Engine Blade Form Detection

PubMed Central

Sun, Bin; Li, Bing

2015-01-01

This paper proposes a rapid method to detect aero-engine blade form, according to the characteristics of an aero-engine blade surface. This method first deduces an inclination error model in free-form surface measurements based on the non-contact laser triangulation principle. Then a four-coordinate measuring system was independently developed, a special fixture was designed according to the blade shape features, and a fast measurement of the blade features path was planned. Finally, by using the inclination error model for correction of acquired data, the measurement error that was caused by tilt form is compensated. As a result the measurement accuracy of the Laser Displacement Sensor was less than 10 μm. After the experimental verification, this method makes full use of optical non-contact measurement fast speed, high precision and wide measuring range of features. Using a standard gauge block as a measurement reference, the coordinate system conversion data is simple and practical. It not only improves the measurement accuracy of the blade surface, but also its measurement efficiency. Therefore, this method increases the value of the measurement of complex surfaces. PMID:26039420

A rapid method to achieve aero-engine blade form detection.

PubMed

Sun, Bin; Li, Bing

2015-06-01

This paper proposes a rapid method to detect aero-engine blade form, according to the characteristics of an aero-engine blade surface. This method first deduces an inclination error model in free-form surface measurements based on the non-contact laser triangulation principle. Then a four-coordinate measuring system was independently developed, a special fixture was designed according to the blade shape features, and a fast measurement of the blade features path was planned. Finally, by using the inclination error model for correction of acquired data, the measurement error that was caused by tilt form is compensated. As a result the measurement accuracy of the Laser Displacement Sensor was less than 10 μm. After the experimental verification, this method makes full use of optical non-contact measurement fast speed, high precision and wide measuring range of features. Using a standard gauge block as a measurement reference, the coordinate system conversion data is simple and practical. It not only improves the measurement accuracy of the blade surface, but also its measurement efficiency. Therefore, this method increases the value of the measurement of complex surfaces.

A new multigroup method for cross-sections that vary rapidly in energy

DOE PAGES

Haut, Terry Scot; Ahrens, Cory D.; Jonko, Alexandra; ...

2016-11-04

Here, we present a numerical method for solving the time-independent thermal radiative transfer (TRT) equation or the neutron transport (NT) equation when the opacity (cross-section) varies rapidly in frequency (energy) on the microscale ε; ε corresponds to the characteristic spacing between absorption lines or resonances, and is much smaller than the macroscopic frequency (energy) variation of interest. The approach is based on a rigorous homogenization of the TRT/NT equation in the frequency (energy) variable. Discretization of the homogenized TRT/NT equation results in a multigroup-type system, and can therefore be solved by standard methods.

Rapid incremental methods for the determination of serum iron and iron-binding capacity

PubMed Central

Beale, R. N.; Bostrom, J. O.; Taylor, R. F.

1961-01-01

Rapid methods depending on differential absorptiometry are described for the determination of the transferrin iron content and the latent iron-binding capacity of blood serum. Each determination requires as little as 0·5 ml. serum. The methods are well adapted for routine use in the `average' laboratory. Three or four sera may be completely analysed in 30 minutes. All operations are carried out in the cells or tubes used for the colorimetric measurements, no precipitation or heating being employed at any stage. Critical investigations of the reliability of the methods are attempted and ranges of normal values are included. PMID:13866116

Automation of a spectrophotometric method for measuring L -carnitine in human blood serum.

PubMed

Galan, A; Padros, A; Arambarri, M; Martin, S

1998-01-01

A spectrometric method for the determination of L-carnitine has been developed based on the reaction of the 5,5' dithiobis-(2-nitrobenzoic) acid (DTNB) and adapted to a Technicon RA-2000 automatic analyser Química Farmacéutica Bayer, S.A.). The detection limit of the method is 13.2 mumol/l, with a measurement interval ranging from 30 to 320 mumoll1. Imprecision and accuracy are good even at levels close to the detection limit (coeffcient of variation of 5.4% for within-run imprecision for a concentration of 35 mumol/l). A good correlation was observed between the method studied and the radiometric method. The method evaluated has suffcient analytical sensitivity to diagnose carnitine deficiencies. The short time period required for sample processing (30 samples in 40min), the simple methodology and apparatus, the ease of personnel training and the low cost of the reagents make this method a good alternative to the classical radiometric method for evaluating serum L-carnitine in clinical laboratories without radioactive installations.

Automation of a spectrophotometric method for measuring L -carnitine in human blood serum

PubMed Central

Galan, Amparo; Padros, Anna; Arambarri, Marta; Martin, Silvia

1998-01-01

A spectrometric method for the determination of L-carnitine has been developed based on the reaction of the 5, 5 ′ dithiobis-(2-nitrobenzoic) acid (DTNB) and adapted to a Technicon RA-2000 automatic analyser Química Farmacéutica Bayer, S.A.). The detection limit of the method is 13.2 μmol/l, with a measurement interval ranging from 30 to 320 μmoll1. Imprecision and accuracy are good even at levels close to the detection limit (coeffcient of variation of 5.4% for within-run imprecision for a concentration of 35 μmol/l). A good correlation was observed between the method studied and the radiometric method. The method evaluated has suffcient analytical sensitivity to diagnose carnitine deficiencies. The short time period required for sample processing (30 samples in 40min), the simple methodology and apparatus, the ease of personnel training and the low cost of the reagents make this method a good alternative to the classical radiometric method for evaluating serum L-carnitine in clinical laboratories without radioactive installations. PMID:18924818

The Rosetta UV imaging spectrometer ALICE: First light optical and radiometric performance results

NASA Astrophysics Data System (ADS)

Slater, D. C.; Stern, S. A.; A'Hearn, M. F.; Bertaux, J. L.; Feldman, P. D.; Festou, M. C.

2000-10-01

We describe the design, scientific objectives, and "first-light" radiometric testing results of the Rosetta/ALICE instrument. ALICE is a lightweight (2.7 kg), low-power (4 W), and low-cost imaging spectrometer optimized for cometary ultraviolet spectroscopy. ALICE, which is funded by NASA (with hardware contributions from CNES, France), will fly on the ESA Rosetta Orbiter to characterize the cometary nucleus, coma, and nucleus/coma coupling of the target comet 46P/Wirtanen. It will obtain spatially-resolved, far-UV spectra of Wirtanen's nucleus and coma in the 700-2050 Å passband with a spectral resolution of 5-10 Å for extended sources that fill the entrance slit's field- of-view. ALICE is also the UV spectrometer model for the PERSI remote sensing suite proposed for the Pluto Kuiper Express (PKE) mission. ALICE uses modern technology to achieve its low mass and low power design specifications. It employs an off-axis telescope feeding a 0.15-m normal incidence Rowland circle spectrograph with a concave (toroidal) holographic reflection grating. The imaging microchannel plate (MCP) detector utilizes dual solar-blind opaque photocathodes of KBr and CsI deposited on a cylindrically-curved (7.5-cm radius) MCP Z-stack, and a matching 2-D cylindrically-curved double delay-line readout array with a 1024 x 32 pixel array format. This array format provides a point source response that is twice that originally proposed (Δ λ 3 Å). Three data taking modes are possible: (i) histogram image mode for 2-D images, (ii) pixel list mode with periodic time hacks for temporal studies, and (iii) count rate mode for broadband photometric studies. Optical and radiometric sensitivity performance results based on subsystem tests of the flight optics, detector, and preliminary integrated system level tests of the integrated ALICE flight model are presented and discussed.

Adapting and Evaluating a Rapid, Low-Cost Method to Enumerate Flies in the Household Setting

PubMed Central

Wolfe, Marlene K.; Dentz, Holly N.; Achando, Beryl; Mureithi, MaryAnne; Wolfe, Tim; Null, Clair; Pickering, Amy J.

2017-01-01

Diarrhea is a leading cause of death among children under 5 years of age worldwide. Flies are important vectors of diarrheal pathogens in settings lacking networked sanitation services. There is no standardized method for measuring fly density in households; many methods are cumbersome and unvalidated. We adapted a rapid, low-cost fly enumeration technique previously developed for industrial settings, the Scudder fly grill, for field use in household settings. We evaluated its performance in comparison to a sticky tape fly trapping method at latrine and food preparation areas among households in rural Kenya. The grill method was more sensitive; it detected the presence of any flies at 80% (433/543) of sampling locations versus 64% (348/543) of locations by the sticky tape. We found poor concordance between the two methods, suggesting that standardizing protocols is important for comparison of fly densities between studies. Fly species identification was feasible with both methods; however, the sticky tape trap allowed for more nuanced identification. Both methods detected a greater presence of bottle flies near latrines compared with food preparation areas (P < 0.01). The grill method detected more flies at the food preparation area compared with near the latrine (P = 0.014) while the sticky tape method detected no difference. We recommend the Scudder grill as a sensitive fly enumeration tool that is rapid and low cost to implement. PMID:27956654

A rapid method for measuring intracellular pH using BCECF-AM.

PubMed

Ozkan, Pinar; Mutharasan, Raj

2002-08-15

A rapid intracellular pH (pH(i)) measurement method based on initial rate of increase of fluorescence ratio of 2',7'-bis(2-carboxyethyl)-5,6-carboxyfluorescein upon dye addition to a cell suspension in growth medium is reported. A dye transport model that describes dye concentration and fluorescence values in intracellular and extracellular spaces provides the mathematical basis for the approach. Experimental results of ammonium chloride challenge response of the two suspension cells, Spodoptera frugiperda and Chinese hamster ovary (CHO) cells, successfully compared with results obtained using traditional perfusion method. Since the cell suspension does not require any preparation, measurement of pH(i) can be completed in about 1 min minimizing any potential errors due to dye leakage.

An evaluation of rapid methods for monitoring vegetation characteristics of wetland bird habitat

USGS Publications Warehouse

Tavernia, Brian G.; Lyons, James E.; Loges, Brian W.; Wilson, Andrew; Collazo, Jaime A.; Runge, Michael C.

2016-01-01

Wetland managers benefit from monitoring data of sufficient precision and accuracy to assess wildlife habitat conditions and to evaluate and learn from past management decisions. For large-scale monitoring programs focused on waterbirds (waterfowl, wading birds, secretive marsh birds, and shorebirds), precision and accuracy of habitat measurements must be balanced with fiscal and logistic constraints. We evaluated a set of protocols for rapid, visual estimates of key waterbird habitat characteristics made from the wetland perimeter against estimates from (1) plots sampled within wetlands, and (2) cover maps made from aerial photographs. Estimated percent cover of annuals and perennials using a perimeter-based protocol fell within 10 percent of plot-based estimates, and percent cover estimates for seven vegetation height classes were within 20 % of plot-based estimates. Perimeter-based estimates of total emergent vegetation cover did not differ significantly from cover map estimates. Post-hoc analyses revealed evidence for observer effects in estimates of annual and perennial covers and vegetation height. Median time required to complete perimeter-based methods was less than 7 percent of the time needed for intensive plot-based methods. Our results show that rapid, perimeter-based assessments, which increase sample size and efficiency, provide vegetation estimates comparable to more intensive methods.

Development of a rapid, robust, and universal picogreen-based method to titer adeno-associated vectors.

PubMed

Piedra, Jose; Ontiveros, Maria; Miravet, Susana; Penalva, Cristina; Monfar, Mercè; Chillon, Miguel

2015-02-01

Recombinant adeno-associated viruses (rAAVs) are promising vectors in preclinical and clinical assays for the treatment of diseases with gene therapy strategies. Recent technological advances in amplification and purification have allowed the production of highly purified rAAV vector preparations. Although quantitative polymerase chain reaction (qPCR) is the current method of choice for titrating rAAV genomes, it shows high variability. In this work, we report a rapid and robust rAAV titration method based on the quantitation of encapsidated DNA with the fluorescent dye PicoGreen®. This method allows detection from 3×10(10) viral genome/ml up to 2.4×10(13) viral genome/ml in a linear range. Contrasted with dot blot or qPCR, the PicoGreen-based assay has less intra- and interassay variability. Moreover, quantitation is rapid, does not require specific primers or probes, and is independent of the rAAV pseudotype analyzed. In summary, development of this universal rAAV-titering method may have substantive implications in rAAV technology.

A Method to Represent Heterogeneous Materials for Rapid Prototyping: The Matryoshka Approach.

PubMed

Lei, Shuangyan; Frank, Matthew C; Anderson, Donald D; Brown, Thomas D

The purpose of this paper is to present a new method for representing heterogeneous materials using nested STL shells, based, in particular, on the density distributions of human bones. Nested STL shells, called Matryoshka models, are described, based on their namesake Russian nesting dolls. In this approach, polygonal models, such as STL shells, are "stacked" inside one another to represent different material regions. The Matryoshka model addresses the challenge of representing different densities and different types of bone when reverse engineering from medical images. The Matryoshka model is generated via an iterative process of thresholding the Hounsfield Unit (HU) data using computed tomography (CT), thereby delineating regions of progressively increasing bone density. These nested shells can represent regions starting with the medullary (bone marrow) canal, up through and including the outer surface of the bone. The Matryoshka approach introduced can be used to generate accurate models of heterogeneous materials in an automated fashion, avoiding the challenge of hand-creating an assembly model for input to multi-material additive or subtractive manufacturing. This paper presents a new method for describing heterogeneous materials: in this case, the density distribution in a human bone. The authors show how the Matryoshka model can be used to plan harvesting locations for creating custom rapid allograft bone implants from donor bone. An implementation of a proposed harvesting method is demonstrated, followed by a case study using subtractive rapid prototyping to harvest a bone implant from a human tibia surrogate.

[Comparison of two methods for rapid determination of C-reactive protein with the Tina-quant].

PubMed

Oremek, G M; Luksaite, R; Bretschneider, I

2008-03-01

C-reactive protein (CRP) as an acute phase protein is an important diagnostic marker for the presence and course of human processes. Out of the acute phase proteins it is one of those the concentrations increase most rapidly with its sensitivity being superior to other markers of inflammation, such as leukocytosis, erythrocytic sedimentation rate, and fever. This study compared two-point-of-care assays with the standard laboratory method Tina-quant CRP processed on a Hitachi 917: the immunofiltration assay NycoCard CRP Whole Blood and the turbidimetric immunoassay Micros CRP. Both methods are carried in the presence of a patient, by using capillary or venous blood. Seventy-eight blood samples were analyzed first in the standard laboratory routine and then by both rapid test assays. The precision of both assays was determined from the confidence interval. The results were statistically analyzed by arithmetic standard deviation mean method, variation coefficient, Spearman correlation index, Wilcoxon and Bland-Altman tests, and Passing-Bablock regression. NycoCard CRP Whole Blood showed a correlation coefficient of R = 0.9838; the precision had a coefficient of variation of CV = 1.8759% while As compared with Tina-quant CRP had R = 0.9934 and CV = 0.9160%. Both assays indicated the same results as Tina-quant CRP. Both Tina-quant CRP and NycoCard CRP Whole Blood give the best fit for the rapid determination of CRP.

Rapid detection of mecA and spa by the loop-mediated isothermal amplification (LAMP) method.

PubMed

Koide, Y; Maeda, H; Yamabe, K; Naruishi, K; Yamamoto, T; Kokeguchi, S; Takashiba, S

2010-04-01

To develop a detection assay for staphylococcal mecA and spa by using loop-mediated isothermal amplification (LAMP) method. Staphylococcus aureus and other related species were subjected to the detection of mecA and spa by both PCR and LAMP methods. The LAMP successfully amplified the genes under isothermal conditions at 64 degrees C within 60 min, and demonstrated identical results with the conventional PCR methods. The detection limits of the LAMP for mecA and spa, by gel electrophoresis, were 10(2) and 10 cells per tube, respectively. The naked-eye inspections were possible with 10(3) and 10 cells for detection of mecA and spa, respectively. The LAMP method was then applied to sputum and dental plaque samples. The LAMP and PCR demonstrated identical results for the plaque samples, although frequency in detection of mecA and spa by the LAMP was relatively lower for the sputum samples when compared to the PCR methods. Application of the LAMP enabled a rapid detection assay for mecA and spa. The assay may be applicable to clinical plaque samples. The LAMP offers an alternative detection assay for mecA and spa with a great advantage of the rapidity.

Polarization impacts on the water-leaving radiance retrieval from above-water radiometric measurements.

PubMed

Harmel, Tristan; Gilerson, Alexander; Tonizzo, Alberto; Chowdhary, Jacek; Weidemann, Alan; Arnone, Robert; Ahmed, Sam

2012-12-10

Above-water measurements of water-leaving radiance are widely used for water-quality monitoring and ocean-color satellite data validation. Reflected skylight in above-water radiometry needs to be accurately estimated prior to derivation of water-leaving radiance. Up-to-date methods to estimate reflection of diffuse skylight on rough sea surfaces are based on radiative transfer simulations and sky radiance measurements. But these methods neglect the polarization state of the incident skylight, which is generally highly polarized. In this paper, the effects of polarization on the sea surface reflectance and the subsequent water-leaving radiance estimation are investigated. We show that knowledge of the polarization field of the diffuse skylight significantly improves above-water radiometry estimates, in particular in the blue part of the spectrum where the reflected skylight is dominant. A newly developed algorithm based on radiative transfer simulations including polarization is described. Its application to the standard Aerosol Robotic Network-Ocean Color and hyperspectral radiometric measurements of the 1.5-year dataset acquired at the Long Island Sound site demonstrates the noticeable importance of considering polarization for water-leaving radiance estimation. In particular it is shown, based on time series of collocated data acquired in coastal waters, that the azimuth range of measurements leading to good-quality data is significantly increased, and that these estimates are improved by more than 12% at 413 nm. Full consideration of polarization effects is expected to significantly improve the quality of the field data utilized for satellite data validation or potential vicarious calibration purposes.

Modified microplate method for rapid and efficient estimation of siderophore produced by bacteria.

PubMed

Arora, Naveen Kumar; Verma, Maya

2017-12-01

In this study, siderophore production by various bacteria amongst the plant-growth-promoting rhizobacteria was quantified by a rapid and efficient method. In total, 23 siderophore-producing bacterial isolates/strains were taken to estimate their siderophore-producing ability by the standard method (chrome azurol sulphonate assay) as well as 96 well microplate method. Production of siderophore was estimated in percent siderophore unit by both the methods. It was observed that data obtained by both methods correlated positively with each other proving the correctness of microplate method. By the modified microplate method, siderophore production by several bacterial strains can be estimated both qualitatively and quantitatively at one go, saving time, chemicals, making it very less tedious, and also being cheaper in comparison with the method currently in use. The modified microtiter plate method as proposed here makes it far easier to screen the plant-growth-promoting character of plant-associated bacteria.

Rapid-viability PCR method for detection of live, virulent Bacillus anthracis in environmental samples.

PubMed

Létant, Sonia E; Murphy, Gloria A; Alfaro, Teneile M; Avila, Julie R; Kane, Staci R; Raber, Ellen; Bunt, Thomas M; Shah, Sanjiv R

2011-09-01

In the event of a biothreat agent release, hundreds of samples would need to be rapidly processed to characterize the extent of contamination and determine the efficacy of remediation activities. Current biological agent identification and viability determination methods are both labor- and time-intensive such that turnaround time for confirmed results is typically several days. In order to alleviate this issue, automated, high-throughput sample processing methods were developed in which real-time PCR analysis is conducted on samples before and after incubation. The method, referred to as rapid-viability (RV)-PCR, uses the change in cycle threshold after incubation to detect the presence of live organisms. In this article, we report a novel RV-PCR method for detection of live, virulent Bacillus anthracis, in which the incubation time was reduced from 14 h to 9 h, bringing the total turnaround time for results below 15 h. The method incorporates a magnetic bead-based DNA extraction and purification step prior to PCR analysis, as well as specific real-time PCR assays for the B. anthracis chromosome and pXO1 and pXO2 plasmids. A single laboratory verification of the optimized method applied to the detection of virulent B. anthracis in environmental samples was conducted and showed a detection level of 10 to 99 CFU/sample with both manual and automated RV-PCR methods in the presence of various challenges. Experiments exploring the relationship between the incubation time and the limit of detection suggest that the method could be further shortened by an additional 2 to 3 h for relatively clean samples.

Optimal estimation and scheduling in aquifer management using the rapid feedback control method

NASA Astrophysics Data System (ADS)

Ghorbanidehno, Hojat; Kokkinaki, Amalia; Kitanidis, Peter K.; Darve, Eric

2017-12-01

Management of water resources systems often involves a large number of parameters, as in the case of large, spatially heterogeneous aquifers, and a large number of "noisy" observations, as in the case of pressure observation in wells. Optimizing the operation of such systems requires both searching among many possible solutions and utilizing new information as it becomes available. However, the computational cost of this task increases rapidly with the size of the problem to the extent that textbook optimization methods are practically impossible to apply. In this paper, we present a new computationally efficient technique as a practical alternative for optimally operating large-scale dynamical systems. The proposed method, which we term Rapid Feedback Controller (RFC), provides a practical approach for combined monitoring, parameter estimation, uncertainty quantification, and optimal control for linear and nonlinear systems with a quadratic cost function. For illustration, we consider the case of a weakly nonlinear uncertain dynamical system with a quadratic objective function, specifically a two-dimensional heterogeneous aquifer management problem. To validate our method, we compare our results with the linear quadratic Gaussian (LQG) method, which is the basic approach for feedback control. We show that the computational cost of the RFC scales only linearly with the number of unknowns, a great improvement compared to the basic LQG control with a computational cost that scales quadratically. We demonstrate that the RFC method can obtain the optimal control values at a greatly reduced computational cost compared to the conventional LQG algorithm with small and controllable losses in the accuracy of the state and parameter estimation.

Advanced radiometric and interferometric milimeter-wave scene simulations

NASA Technical Reports Server (NTRS)

Hauss, B. I.; Moffa, P. J.; Steele, W. G.; Agravante, H.; Davidheiser, R.; Samec, T.; Young, S. K.

1993-01-01

Smart munitions and weapons utilize various imaging sensors (including passive IR, active and passive millimeter-wave, and visible wavebands) to detect/identify targets at short standoff ranges and in varied terrain backgrounds. In order to design and evaluate these sensors under a variety of conditions, a high-fidelity scene simulation capability is necessary. Such a capability for passive millimeter-wave scene simulation exists at TRW. TRW's Advanced Radiometric Millimeter-Wave Scene Simulation (ARMSS) code is a rigorous, benchmarked, end-to-end passive millimeter-wave scene simulation code for interpreting millimeter-wave data, establishing scene signatures and evaluating sensor performance. In passive millimeter-wave imaging, resolution is limited due to wavelength and aperture size. Where high resolution is required, the utility of passive millimeter-wave imaging is confined to short ranges. Recent developments in interferometry have made possible high resolution applications on military platforms. Interferometry or synthetic aperture radiometry allows the creation of a high resolution image with a sparsely filled aperture. Borrowing from research work in radio astronomy, we have developed and tested at TRW scene reconstruction algorithms that allow the recovery of the scene from a relatively small number of spatial frequency components. In this paper, the TRW modeling capability is described and numerical results are presented.

An analysis of new techniqes for radiometric correction of LANDSAT-4 Thematic Mapper images. [Terrebonne Bay, Louisiana and Grand Bahamas scenes

NASA Technical Reports Server (NTRS)

Kogut, J.; Larduinat, E.; Fitzgerald, M.

1983-01-01

The utility of methods for generating TM RLUTS which can improve the quality of the resultant images was investigated. The TM-CCT-ADDS tape was changed to account for a different collection window for the calibration data. Several scenes of Terrebonne Bay, Louisiana and the Grand Bahamas were analyzed to evaluate the radiometric corrections operationally applied to the image data and to investigate several techniques for reducing striping in the images. Printer plots for the TM shutter data were produced and detector statistics were compiled and plotted. These statistics included various combinations of the average shutter counts for each scan before and after DC restore for forward and reverse scans. Results show that striping is caused by the detectors becoming saturated when they view a bright cloud and depress the DC restore level.

Rapid Microcystin Determination Using a Paper Spray Ionization Method with a Time-of-Flight Mass Spectrometry System.

PubMed

Zhu, Xiaoqiang; Huang, Zhengxu; Gao, Wei; Li, Xue; Li, Lei; Zhu, Hui; Mo, Ting; Huang, Bao; Zhou, Zhen

2016-07-13

The eutrophication of surface water sources and climate changes have resulted in an annual explosion of cyanobacterial blooms in many irrigating and drinking water resources. To decrease health risks to the public, a rapid real time method for the synchronous determination of two usually harmful microcystins (MC-RR and MC-LR) in environmental water samples was built by employing a paper spray ionization method coupled with a time-of-flight mass spectrometer system. With this approach, direct analysis of microcystin mixtures without sample preparation has been achieved. Rapid detection was performed, simulating the release process of microcystins in reservoir water samples, and the routine detection frequency was every three minutes. The identification time of microcystins was reduced from several hours to a few minutes. The limit of detection is 1 μg/L, and the limit of quantitation is 3 μg/L. This method displays the ability for carrying out rapid, direct, and high-throughput experiments for determination of microcystins, and it would be of significant interest for environmental and food safety applications.

Rapid method for the determination of 226Ra in hydraulic fracturing wastewater samples

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

Maxwell, Sherrod L.; Culligan, Brian K.; Warren, Richard A.

A new method that rapidly preconcentrates and measures 226Ra from hydraulic fracturing wastewater samples was developed in the Savannah River Environmental Laboratory. The method improves the quality of 226Ra measurements using gamma spectrometry by providing up to 100x preconcentration of 226Ra from this difficult sample matrix, which contains very high levels of calcium, barium, strontium, magnesium and sodium. The high chemical yield, typically 80-90%, facilitates a low detection limit, important for lower level samples, and indicates method ruggedness. Ba-133 tracer is used to determine chemical yield and correct for geometry-related counting issues. The 226Ra sample preparation takes < 2 hours.

Rapid method for the determination of 226Ra in hydraulic fracturing wastewater samples

DOE PAGES

Maxwell, Sherrod L.; Culligan, Brian K.; Warren, Richard A.; ...

2016-03-24

A new method that rapidly preconcentrates and measures 226Ra from hydraulic fracturing wastewater samples was developed in the Savannah River Environmental Laboratory. The method improves the quality of 226Ra measurements using gamma spectrometry by providing up to 100x preconcentration of 226Ra from this difficult sample matrix, which contains very high levels of calcium, barium, strontium, magnesium and sodium. The high chemical yield, typically 80-90%, facilitates a low detection limit, important for lower level samples, and indicates method ruggedness. Ba-133 tracer is used to determine chemical yield and correct for geometry-related counting issues. The 226Ra sample preparation takes < 2 hours.

The Landsat Data Continuity Mission Operational Land Imager: Radiometric Performance

NASA Technical Reports Server (NTRS)

Markham, Brian; Dabney, Philip; Pedelty, Jeffrey

2011-01-01

The Operational Land Imager (OLI) is one of two instruments to fly on the Landsat Data Continuity Mission (LDCM), which is scheduled to launch in December 2012 to become the 8th in the series of Landsat satellites. The OLI images in the solar reflective part of the spectrum, with bands similar to bands 1-5, 7 and the panchromatic band on the Landsat-7 ETM+ instrument. In addition, it has a 20 nm bandpass spectral band at 443 nm for coastal and aerosol studies and a 30 nm band at 1375 nm to aid in cirrus cloud detection. Like ETM+, spatial resolution is 30 m in the all but the panchromatic band, which is 15 meters. OLI is a pushbroom radiometer with approximately 6000 detectors per 30 meter band as opposed to the 16 detectors per band on the whiskbroom ETM+. Data are quantized to 12 bits on OLI as opposed to 8 bits on ETM+ to take advantage of the improved signal to noise ratio provided by the pushbroom design. The saturation radiances are higher on OLI than ETM+ to effectively eliminate saturation issues over bright Earth targets. OLI includes dual solar diffusers for on-orbit absolute and relative (detector to detector) radiometric calibration. Additionally, OLI has 3 sets of on-board lamps that illuminate the OLI focal plane through the full optical system, providing additional checks on the OLI's response[l]. OLI has been designed and built by Ball Aerospace & Technology Corp. (BATC) and is currently undergoing testing and calibration in preparation for delivery in Spring 2011. Final pre-launch performance results should be available in time for presentation at the conference. Preliminary results will be presented below. These results are based on the performance of the Engineering Development Unit (EDU) that was radiometrically tested at the integrated instrument level in 2010 and assembly level measurements made on the flight unit. Signal-to-Noise (SNR) performance: One of the advantages of a pushbroom system is the increased dwell time of the detectors

Developing rapid methods for analyzing upland riparian functions and values.

PubMed

Hruby, Thomas

2009-06-01

Regulators protecting riparian areas need to understand the integrity, health, beneficial uses, functions, and values of this resource. Up to now most methods providing information about riparian areas are based on analyzing condition or integrity. These methods, however, provide little information about functions and values. Different methods are needed that specifically address this aspect of riparian areas. In addition to information on functions and values, regulators have very specific needs that include: an analysis at the site scale, low cost, usability, and inclusion of policy interpretations. To meet these needs a rapid method has been developed that uses a multi-criteria decision matrix to categorize riparian areas in Washington State, USA. Indicators are used to identify the potential of the site to provide a function, the potential of the landscape to support the function, and the value the function provides to society. To meet legal needs fixed boundaries for assessment units are established based on geomorphology, the distance from "Ordinary High Water Mark" and different categories of land uses. Assessment units are first classified based on ecoregions, geomorphic characteristics, and land uses. This simplifies the data that need to be collected at a site, but it requires developing and calibrating a separate model for each "class." The approach to developing methods is adaptable to other locations as its basic structure is not dependent on local conditions.

Simultaneous determination of effective carrier lifetime and resistivity of Si wafers using the nonlinear nature of photocarrier radiometric signals

NASA Astrophysics Data System (ADS)

Sun, Qiming; Melnikov, Alexander; Wang, Jing; Mandelis, Andreas

2018-04-01

A rigorous treatment of the nonlinear behavior of photocarrier radiometric (PCR) signals is presented theoretically and experimentally for the quantitative characterization of semiconductor photocarrier recombination and transport properties. A frequency-domain model based on the carrier rate equation and the classical carrier radiative recombination theory was developed. The derived concise expression reveals different functionalities of the PCR amplitude and phase channels: the phase bears direct quantitative correlation with the carrier effective lifetime, while the amplitude versus the estimated photocarrier density dependence can be used to extract the equilibrium majority carrier density and thus, resistivity. An experimental ‘ripple’ optical excitation mode (small modulation depth compared to the dc level) was introduced to bypass the complicated ‘modulated lifetime’ problem so as to simplify theoretical interpretation and guarantee measurement self-consistency and reliability. Two Si wafers with known resistivity values were tested to validate the method.

Making SAR Data Accessible - ASF's ALOS PALSAR Radiometric Terrain Correction Project

NASA Astrophysics Data System (ADS)

Meyer, F. J.; Arko, S. A.; Gens, R.

2015-12-01

While SAR data have proven valuable for a wide range of geophysical research questions, so far, largely only the SAR-educated science communities have been able to fully exploit the information content of internationally available SAR archives. The main issues that have been preventing a more widespread utilization of SAR are related to (1) the diversity and complexity of SAR data formats, (2) the complexity of the processing flows needed to extract geophysical information from SAR, (3) the lack of standardization and automation of these processing flows, and (4) the often ignored geocoding procedures, leaving the data in image coordinate space. In order to improve upon this situation, ASF's radiometric terrain-correction (RTC) project is generating uniformly formatted and easily accessible value-added products from the ASF Distributed Active Archive Center's (DAAC) five-year archive of JAXA's ALOS PALSAR sensor. Specifically, the project applies geometric and radiometric corrections to SAR data to allow for an easy and direct combination of obliquely acquired SAR data with remote sensing imagery acquired in nadir observation geometries. Finally, the value-added data is provided to the user in the broadly accepted Geotiff format, in order to support the easy integration of SAR data into GIS environments. The goal of ASF's RTC project is to make SAR data more accessible and more attractive to the broader SAR applications community, especially to those users that currently have limited SAR expertise. Production of RTC products commenced October 2014 and will conclude late in 2015. As of July 2015, processing of 71% of ASF's ALOS PALSAR archive was completed. Adding to the utility of this dataset are recent changes to the data access policy that allow the full-resolution RTC products to be provided to the public, without restriction. In this paper we will introduce the processing flow that was developed for the RTC project and summarize the calibration and validation

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.

Ultrasonic-assisted deacetylation of cellulose acetate nanofibers: A rapid method to produce cellulose nanofibers.

PubMed

Ahmed, Farooq; Ayoub Arbab, Alvira; Jatoi, Abdul Wahab; Khatri, Muzamil; Memon, Najma; Khatri, Zeeshan; Kim, Ick Soo

2017-05-01

Herein we report a rapid method for deacetylation of cellulose acetate (CA) nanofibers in order to produce cellulose nanofibers using ultrasonic energy. The CA nanofibers were fabricated via electrospinning thereby treated with NaOH and NaOH/EtOH solutions at various pH levels for 30, 60 and 90min assisted by ultrasonic energy. The nanofiber webs were optimized by degree of deacetylation (DD%) and wicking behavior. The resultant nanofibers were further characterized by FTIR, SEM, WAXD, DSC analysis. The DD% and FTIR results confirmed a complete conversion of CA nanofibers to cellulose nanofibers within 1h with substantial increase of wicking height. Nanofibers morphology under SEM showed slightly swelling and no damage of nanofibers observed by use of ultrasonic energy. The results of ultrasonic-assisted deacetylation are comparable with the conventional deacetylation. Our rapid method offers substantially reduced deacetylation time from 30h to just 1h, thanks to the ultrasonic energy. Copyright © 2016 Elsevier B.V. All rights reserved.

Rapid analysis of fertilizers by the direct-reading thermometric method.

PubMed

Sajó, I; Sipos, B

1972-05-01

The authors have developed rapid methods for the determination of the main components of fertilizers, namely phosphate, potassium and nitrogen fixed in various forms. In the absence of magnesium ions phosphate is precipitated with magnesia mixture; in the presence of magnesium ions ammonium phosphomolybdate is precipitated and the excess of molybdate is reacted with hydrogen peroxide. Potassium is determined by precipitation with silico-fluoride. For nitrogen fixed as ammonium salts the ammonium ions are condensed in a basic solution with formalin to hexamethylenetetramine; for nitrogen fixed as carbamide the latter is decomposed with sodium nitrite; for nitrogen fixed as nitrate the latter is reduced with titanium(III). In each case the temperature change of the test solution is measured. Practically all essential components of fertilizers may be determined by direct-reading thermometry; with this method and special apparatus the time of analysis is reduced to at most about 15 min for any determination.

Rapid tooling method for soft customized removable oral appliances.

PubMed

Salmi, Mika; Tuomi, Jukka; Sirkkanen, Rauno; Ingman, Tuula; Mäkitie, Antti

2012-01-01

Traditionally oral appliances i.e. removable orthodontic appliances, bite splints and snoring / sleep apnea appliances are made with alginate impressions and wax registrations. Our aim was to describe the process of manufacturing customized oral appliances with a new technique i.e. rapid tooling method. The appliance should ideally be custom made to match the teeth. An orthodontic patient, scheduled for conventional orthodontic treatment, served as a study subject. After a precise clinical and radiographic examination, the approach was to digitize the patient's dental arches and then to correct them virtually by computer. Additive manufacturing was then used to fabricate a mould for a soft customized appliance. The mould was manufactured using stereolithography from Somos ProtoGen O-XT 18420 material. Casting material for the mould to obtain the final appliance was silicone. As a result we managed to create a customized soft orthodontic appliance. Also, the accuracy of the method was found to be adequate. Two versions of the described device were manufactured: one with small and one with moderate orthodontic force. The study person also gave information on the subjective patient adaptation aspects of the oral appliance.

A Maximum Likelihood Approach to Determine Sensor Radiometric Response Coefficients for NPP VIIRS Reflective Solar Bands

NASA Technical Reports Server (NTRS)

Lei, Ning; Chiang, Kwo-Fu; Oudrari, Hassan; Xiong, Xiaoxiong

2011-01-01

Optical sensors aboard Earth orbiting satellites such as the next generation Visible/Infrared Imager/Radiometer Suite (VIIRS) assume that the sensors radiometric response in the Reflective Solar Bands (RSB) is described by a quadratic polynomial, in relating the aperture spectral radiance to the sensor Digital Number (DN) readout. For VIIRS Flight Unit 1, the coefficients are to be determined before launch by an attenuation method, although the linear coefficient will be further determined on-orbit through observing the Solar Diffuser. In determining the quadratic polynomial coefficients by the attenuation method, a Maximum Likelihood approach is applied in carrying out the least-squares procedure. Crucial to the Maximum Likelihood least-squares procedure is the computation of the weight. The weight not only has a contribution from the noise of the sensor s digital count, with an important contribution from digitization error, but also is affected heavily by the mathematical expression used to predict the value of the dependent variable, because both the independent and the dependent variables contain random noise. In addition, model errors have a major impact on the uncertainties of the coefficients. The Maximum Likelihood approach demonstrates the inadequacy of the attenuation method model with a quadratic polynomial for the retrieved spectral radiance. We show that using the inadequate model dramatically increases the uncertainties of the coefficients. We compute the coefficient values and their uncertainties, considering both measurement and model errors.

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.

Absolute radiometric calibration of Landsat using a pseudo invariant calibration site

USGS Publications Warehouse

Helder, D.; Thome, K.J.; Mishra, N.; Chander, G.; Xiong, Xiaoxiong; Angal, A.; Choi, Tae-young

2013-01-01

Pseudo invariant calibration sites (PICS) have been used for on-orbit radiometric trending of optical satellite systems for more than 15 years. This approach to vicarious calibration has demonstrated a high degree of reliability and repeatability at the level of 1-3% depending on the site, spectral channel, and imaging geometries. A variety of sensors have used this approach for trending because it is broadly applicable and easy to implement. Models to describe the surface reflectance properties, as well as the intervening atmosphere have also been developed to improve the precision of the method. However, one limiting factor of using PICS is that an absolute calibration capability has not yet been fully developed. Because of this, PICS are primarily limited to providing only long term trending information for individual sensors or cross-calibration opportunities between two sensors. This paper builds an argument that PICS can be used more extensively for absolute calibration. To illustrate this, a simple empirical model is developed for the well-known Libya 4 PICS based on observations by Terra MODIS and EO-1 Hyperion. The model is validated by comparing model predicted top-of-atmosphere reflectance values to actual measurements made by the Landsat ETM+ sensor reflective bands. Following this, an outline is presented to develop a more comprehensive and accurate PICS absolute calibration model that can be Système international d'unités (SI) traceable. These initial concepts suggest that absolute calibration using PICS is possible on a broad scale and can lead to improved on-orbit calibration capabilities for optical satellite sensors.

Updated radiometric calibration for the Landsat-5 thematic mapper reflective bands

USGS Publications Warehouse

Helder, D.L.; Markham, B.L.; Thome, K.J.; Barsi, J.A.; Chander, G.; Malla, R.

2008-01-01

The Landsat-5 Thematic Mapper (TM) has been the workhorse of the Landsat system. Launched in 1984, it continues collecting data through the time frame of this paper. Thus, it provides an invaluable link to the past history of the land features of the Earth's surface, and it becomes imperative to provide an accurate radiometric calibration of the reflective bands to the user community. Previous calibration has been based on information obtained from prelaunch, the onboard calibrator, vicarious calibration attempts, and cross-calibration with Landsat-7. Currently, additional data sources are available to improve this calibration. Specifically, improvements in vicarious calibration methods and development of the use of pseudoinvariant sites for trending provide two additional independent calibration sources. The use of these additional estimates has resulted in a consistent calibration approach that ties together all of the available calibration data sources. Results from this analysis indicate a simple exponential, or a constant model may be used for all bands throughout the lifetime of Landsat-5 TM. Where previously time constants for the exponential models were approximately one year, the updated model has significantly longer time constants in bands 1-3. In contrast, bands 4, 5, and 7 are shown to be best modeled by a constant. The models proposed in this paper indicate calibration knowledge of 5% or better early in life, decreasing to nearly 2% later in life. These models have been implemented at the U.S. Geological Survey Earth Resources Observation and Science (EROS) and are the default calibration used for all Landsat TM data now distributed through EROS. ?? 2008 IEEE.

A simple method to relate microwave radiances to upper tropospheric humidity

NASA Astrophysics Data System (ADS)

Buehler, S. A.; John, V. O.

2005-01-01

A brightness temperature (BT) transformation method can be applied to microwave data to retrieve Jacobian weighted upper tropospheric relative humidity (UTH) in a broad layer centered roughly between 6 and 8 km altitude. The UTH bias is below 4% RH, and the relative UTH bias below 20%. The UTH standard deviation is between 2 and 6.5% RH in absolute numbers, or between 10 and 27% in relative numbers. The standard deviation is dominated by the regression noise, resulting from vertical structure not accounted for by the simple transformation relation. The UTH standard deviation due to radiometric noise alone has a relative standard deviation of approximately 7% for a radiometric noise level of 1 K. The retrieval performance was shown to be of almost constant quality for all viewing angles and latitudes, except for problems at high latitudes due to surface effects. A validation of AMSU UTH against radiosonde UTH shows reasonable agreement if known systematic differences between AMSU and radiosonde are taken into account. When the method is applied to supersaturation studies, regression noise and radiometric noise could lead to an apparent supersaturation even if there were no supersaturation. For a radiometer noise level of 1 K the drop-off slope of the apparent supersaturation is 0.17% RH-1, for a noise level of 2 K the slope is 0.12% RH-1. The main conclusion from this study is that the BT transformation method is very well suited for microwave data. Its particular strength is in climatological applications where the simplicity and the a priori independence are key advantages.

Rapid simulation of spatial epidemics: a spectral method.

PubMed

Brand, Samuel P C; Tildesley, Michael J; Keeling, Matthew J

2015-04-07

Spatial structure and hence the spatial position of host populations plays a vital role in the spread of infection. In the majority of situations, it is only possible to predict the spatial spread of infection using simulation models, which can be computationally demanding especially for large population sizes. Here we develop an approximation method that vastly reduces this computational burden. We assume that the transmission rates between individuals or sub-populations are determined by a spatial transmission kernel. This kernel is assumed to be isotropic, such that the transmission rate is simply a function of the distance between susceptible and infectious individuals; as such this provides the ideal mechanism for modelling localised transmission in a spatial environment. We show that the spatial force of infection acting on all susceptibles can be represented as a spatial convolution between the transmission kernel and a spatially extended 'image' of the infection state. This representation allows the rapid calculation of stochastic rates of infection using fast-Fourier transform (FFT) routines, which greatly improves the computational efficiency of spatial simulations. We demonstrate the efficiency and accuracy of this fast spectral rate recalculation (FSR) method with two examples: an idealised scenario simulating an SIR-type epidemic outbreak amongst N habitats distributed across a two-dimensional plane; the spread of infection between US cattle farms, illustrating that the FSR method makes continental-scale outbreak forecasting feasible with desktop processing power. The latter model demonstrates which areas of the US are at consistently high risk for cattle-infections, although predictions of epidemic size are highly dependent on assumptions about the tail of the transmission kernel. Copyright © 2015 Elsevier Ltd. All rights reserved.

RAPID AND PRECISE METHOD FOR MEASURING STABLE CARBON ISOTOPE RATIOS OF DISSOLVED INORGANIC CARBON

EPA Science Inventory

We describe a method for rapid preparation, concentration and stable isotopic analysis of dissolved inorganic carbon (d13C-DIC). Liberation of CO2 was accomplished by placing 100 ?l phosphoric acid and 0.9 ml water in an evacuated 1.7-ml gas chromatography (GC) injection vial. Fo...

A Method to Represent Heterogeneous Materials for Rapid Prototyping: The Matryoshka Approach

PubMed Central

Lei, Shuangyan; Frank, Matthew C.; Anderson, Donald D.; Brown, Thomas D.

2015-01-01

Purpose The purpose of this paper is to present a new method for representing heterogeneous materials using nested STL shells, based, in particular, on the density distributions of human bones. Design/methodology/approach Nested STL shells, called Matryoshka models, are described, based on their namesake Russian nesting dolls. In this approach, polygonal models, such as STL shells, are “stacked” inside one another to represent different material regions. The Matryoshka model addresses the challenge of representing different densities and different types of bone when reverse engineering from medical images. The Matryoshka model is generated via an iterative process of thresholding the Hounsfield Unit (HU) data using computed tomography (CT), thereby delineating regions of progressively increasing bone density. These nested shells can represent regions starting with the medullary (bone marrow) canal, up through and including the outer surface of the bone. Findings The Matryoshka approach introduced can be used to generate accurate models of heterogeneous materials in an automated fashion, avoiding the challenge of hand-creating an assembly model for input to multi-material additive or subtractive manufacturing. Originality/Value This paper presents a new method for describing heterogeneous materials: in this case, the density distribution in a human bone. The authors show how the Matryoshka model can be used to plan harvesting locations for creating custom rapid allograft bone implants from donor bone. An implementation of a proposed harvesting method is demonstrated, followed by a case study using subtractive rapid prototyping to harvest a bone implant from a human tibia surrogate. PMID:26120277

Statistical Methods for Rapid Aerothermal Analysis and Design Technology: Validation

NASA Technical Reports Server (NTRS)

DePriest, Douglas; Morgan, Carolyn

2003-01-01

The cost and safety goals for NASA s next generation of reusable launch vehicle (RLV) will require that rapid high-fidelity aerothermodynamic design tools be used early in the design cycle. To meet these requirements, it is desirable to identify adequate statistical models that quantify and improve the accuracy, extend the applicability, and enable combined analyses using existing prediction tools. The initial research work focused on establishing suitable candidate models for these purposes. The second phase is focused on assessing the performance of these models to accurately predict the heat rate for a given candidate data set. This validation work compared models and methods that may be useful in predicting the heat rate.

Note: Non-invasive optical method for rapid determination of alignment degree of oriented nanofibrous layers

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

Pokorny, M.; Rebicek, J.; Klemes, J.

2015-10-15

This paper presents a rapid non-destructive method that provides information on the anisotropic internal structure of nanofibrous layers. A laser beam of a wavelength of 632.8 nm is directed at and passes through a nanofibrous layer prepared by electrostatic spinning. Information about the structural arrangement of nanofibers in the layer is directly visible in the form of a diffraction image formed on a projection screen or obtained from measured intensities of the laser beam passing through the sample which are determined by the dependency of the angle of the main direction of polarization of the laser beam on the axismore » of alignment of nanofibers in the sample. Both optical methods were verified on Polyvinyl alcohol (PVA) nanofibrous layers (fiber diameter of 470 nm) with random, single-axis aligned and crossed structures. The obtained results match the results of commonly used methods which apply the analysis of electron microscope images. The presented simple method not only allows samples to be analysed much more rapidly and without damaging them but it also makes possible the analysis of much larger areas, up to several square millimetres, at the same time.« less

A rapid method to visualize von willebrand factor multimers by using agarose gel electrophoresis, immunolocalization and luminographic detection.

PubMed

Krizek, D R; Rick, M E

2000-03-15

A highly sensitive and rapid clinical method for the visualization of the multimeric structure of von Willebrand Factor in plasma and platelets is described. The method utilizes submerged horizontal agarose gel electrophoresis, followed by transfer of the von Willebrand Factor onto a polyvinylidine fluoride membrane, and immunolocalization and luminographic visualization of the von Willebrand Factor multimeric pattern. This method distinguishes type 1 from types 2A and 2B von Willebrand disease, allowing timely evaluation and classification of von Willebrand Factor in patient plasma. It also allows visualization of the unusually high molecular weight multimers present in platelets. There are several major advantages to this method including rapid processing, simplicity of gel preparation, high sensitivity to low concentrations of von Willebrand Factor, and elimination of radioactivity.

Rapid fabrication method of a microneedle mold with controllable needle height and width.

PubMed

Lin, Yen-Heng; Lee, I-Chi; Hsu, Wei-Chieh; Hsu, Ching-Hong; Chang, Kai-Ping; Gao, Shao-Syuan

2016-10-01

The main issue of transdermal drug delivery is that macromolecular drugs cannot diffuse through the stratum corneum of skin. Many studies have pursued micro-sized needles encapsulated with drugs to overcome this problem, as these needles can pierce the stratum corneum and allow drugs to enter the circulatory system of the human body. However, most microneedle fabrication processes are time-consuming and require expensive equipment. In this study, we demonstrate a rapid method for fabricating a microneedle mold using drawing lithography and a UV-cured resin. The mold was filled with a water-soluble material, polyvinylpyrrolidone (PVP), which was then demolded to produce a water-soluble microneedle array. The results of an in vitro skin insertion test using PVP microneedles and pig ear skin demonstrated the feasibility of the microneedle mold. In addition, by controlling the viscosity of the UV-cured resin through various heat treatments, microneedles with different heights and aspect ratios were produced. Compared with other methods, this technology significantly simplifies and accelerates the mold fabrication process. In addition, the required equipment is relatively simple and inexpensive. Through this technology, we can rapidly fabricate microneedle molds with controllable dimensions for various applications.

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.

Pressure-jump induced rapid solidification of melt: a method of preparing amorphous materials

NASA Astrophysics Data System (ADS)

Liu, Xiuru; Jia, Ru; Zhang, Doudou; Yuan, Chaosheng; Shao, Chunguang; Hong, Shiming

2018-04-01

By using a self-designed pressure-jump apparatus, we investigated the melt solidification behavior in rapid compression process for several kinds of materials, such as elementary sulfur, polymer polyether-ether-ketone (PEEK) and poly-ethylene-terephthalate, alloy La68Al10Cu20Co2 and Nd60Cu20Ni10Al10. Experimental results clearly show that their melts could be solidified to be amorphous states through the rapid compression process. Bulk amorphous PEEK with 24 mm in diameter and 12 mm in height was prepared, which exceeds the size obtained by melt quenching method. The bulk amorphous sulfur thus obtained exhibited extraordinarily high thermal stability, and an abnormal exothermic transition to liquid sulfur was observed at around 396 K for the first time. Furthermore, it is suggested that the glass transition pressure and critical compression rate exist to form the amorphous phase. This approach of rapid compression is very attractive not only because it is a new technique of make bulk amorphous materials, but also because novel properties are expected in the amorphous materials solidified by the pressure-jump within milliseconds or microseconds.

Rapid concentration and sensitive detection of hookworm ova from wastewater matrices using a real-time PCR method.

PubMed

Gyawali, P; Sidhu, J P S; Ahmed, W; Jagals, P; Toze, S

2015-12-01

The risk of human hookworm infections from land application of wastewater matrices could be high in regions with high hookworm prevalence. A rapid, sensitive and specific hookworm detection method from wastewater matrices is required in order to assess human health risks. Currently available methods used to identify hookworm ova to the species level are time consuming and lack accuracy. In this study, a real-time PCR method was developed for the rapid, sensitive and specific detection of canine hookworm (Ancylostoma caninum) ova from wastewater matrices. A. caninum was chosen because of its morphological similarity to the human hookworm (Ancylostoma duodenale and Necator americanus). The newly developed PCR method has high detection sensitivity with the ability to detect less than one A. caninum ova from 1 L of secondary treated wastewater at the mean threshold cycle (CT) values ranging from 30.1 to 34.3. The method is also able to detect four A. caninum ova from 1 L of raw wastewater and from ∼4 g of treated sludge with mean CT values ranging from 35.6 to 39.8 and 39.8 to 39.9, respectively. The better detection sensitivity obtained for secondary treated wastewater compared to raw wastewater and sludge samples could be attributed to sample turbidity. The proposed method appears to be rapid, sensitive and specific compared to traditional methods and has potential to aid in the public health risk assessment associated with land application of wastewater matrices. Furthermore, the method can be adapted to detect other helminth ova of interest from wastewater matrices. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

Diagnostic Performance of a Rapid Magnetic Resonance Imaging Method of Measuring Hepatic Steatosis

PubMed Central

House, Michael J.; Gan, Eng K.; Adams, Leon A.; Ayonrinde, Oyekoya T.; Bangma, Sander J.; Bhathal, Prithi S.; Olynyk, John K.; St. Pierre, Tim G.

2013-01-01

Objectives Hepatic steatosis is associated with an increased risk of developing serious liver disease and other clinical sequelae of the metabolic syndrome. However, visual estimates of steatosis from histological sections of biopsy samples are subjective and reliant on an invasive procedure with associated risks. The aim of this study was to test the ability of a rapid, routinely available, magnetic resonance imaging (MRI) method to diagnose clinically relevant grades of hepatic steatosis in a cohort of patients with diverse liver diseases. Materials and Methods Fifty-nine patients with a range of liver diseases underwent liver biopsy and MRI. Hepatic steatosis was quantified firstly using an opposed-phase, in-phase gradient echo, single breath-hold MRI methodology and secondly, using liver biopsy with visual estimation by a histopathologist and by computer-assisted morphometric image analysis. The area under the receiver operating characteristic (ROC) curve was used to assess the diagnostic performance of the MRI method against the biopsy observations. Results The MRI approach had high sensitivity and specificity at all hepatic steatosis thresholds. Areas under ROC curves were 0.962, 0.993, and 0.972 at thresholds of 5%, 33%, and 66% liver fat, respectively. MRI measurements were strongly associated with visual (r2 = 0.83) and computer-assisted morphometric (r2 = 0.84) estimates of hepatic steatosis from histological specimens. Conclusions This MRI approach, using a conventional, rapid, gradient echo method, has high sensitivity and specificity for diagnosing liver fat at all grades of steatosis in a cohort with a range of liver diseases. PMID:23555650

A simple, rapid and inexpensive screening method for the identification of Pythium insidiosum.

PubMed

Tondolo, Juliana Simoni Moraes; Loreto, Erico Silva; Denardi, Laura Bedin; Mario, Débora Alves Nunes; Alves, Sydney Hartz; Santurio, Janio Morais

2013-04-01

Growth of Pythium insidiosum mycelia around minocycline disks (30μg) did not occur within 7days of incubation at 35°C when the isolates were grown on Sabouraud, corn meal, Muller-Hinton or RPMI agar. This technique offers a simple and rapid method for the differentiation of P. insidiosum from true filamentous fungi. Copyright © 2013 Elsevier B.V. All rights reserved.

Ex vitro composite plants: an inexpensive, rapid method for root biology.

PubMed

Collier, Ray; Fuchs, Beth; Walter, Nathalie; Kevin Lutke, William; Taylor, Christopher G

2005-08-01

Plant transformation technology is frequently the rate-limiting step in gene function analysis in non-model plants. An important tool for root biologists is the Agrobacterium rhizogenes-derived composite plant, which has made possible genetic analyses in a wide variety of transformation recalcitrant dicotyledonous plants. The novel, rapid and inexpensive ex vitro method for producing composite plants described in this report represents a significant advance over existing composite plant induction protocols, which rely on expensive and time-consuming in vitro conditions. The utility of the new system is validated by expression and RNAi silencing of GFP in transgenic roots of composite plants, and is bolstered further by experimental disruption, via RNAi silencing, of endogenous plant resistance to the plant parasitic nematode Meloidogyne incognita in transgenic roots of Lycopersicon esculentum cv. Motelle composite plants. Critical parameters of the method are described and discussed herein.

Rapid, convenient method for screening imidazole-containing compounds for heme oxygenase inhibition.

PubMed

Vlahakis, Jason Z; Rahman, Mona N; Roman, Gheorghe; Jia, Zongchao; Nakatsu, Kanji; Szarek, Walter A

2011-01-01

Sensitive assays for measuring heme oxygenase activity have been based on the gas-chromatographic detection of carbon monoxide using elaborate, expensive equipment. The present study describes a rapid and convenient method for screening imidazole-containing candidates for inhibitory activity against heme oxygenase using a plate reader, based on the spectroscopic evaluation of heme degradation. A PowerWave XS plate reader was used to monitor the absorbance (as a function of time) of heme bound to purified truncated human heme oxygenase-1 (hHO-1) in the individual wells of a standard 96-well plate (with or without the addition of a test compound). The degradation of heme by heme oxygenase-1 was initiated using l-ascorbic acid, and the collected relevant absorbance data were analyzed by three different methods to calculate the percent control activity occurring in wells containing test compounds relative to that occurring in control wells with no test compound present. In the cases of wells containing inhibitory compounds, significant shifts in λ(max) from 404 to near 412 nm were observed as well as a decrease in the rate of heme degradation relative to that of the control. Each of the three methods of data processing (overall percent drop in absorbance over 1.5h, initial rate of reaction determined over the first 5 min, and estimated pseudo first-order reaction rate constant determined over 1.5h) gave similar and reproducible results for percent control activity. The fastest and easiest method of data analysis was determined to be that using initial rates, involving data acquisition for only 5 min once reactions have been initiated using l-ascorbic acid. The results of the study demonstrate that this simple assay based on the spectroscopic detection of heme represents a rapid, convenient method to determine the relative inhibitory activity of candidate compounds, and is useful in quickly screening a series or library of compounds for heme oxygenase inhibition

Bolometric kinetic inductance detector technology for sub-millimeter radiometric imaging

NASA Astrophysics Data System (ADS)

Hassel, Juha; Timofeev, Andrey V.; Vesterinen, Visa; Sipola, Hannu; Helistö, Panu; Aikio, Mika; Mäyrä, Aki; Grönberg, Leif; Luukanen, Arttu

2015-10-01

Radiometric sub-millimeter imaging is a candidate technology especially in security screening applications utilizing the property of radiation in the band of 0.2 - 1.0 THz to penetrate through dielectric substances such as clothing. The challenge of the passive technology is the fact that the irradiance corresponding to the blackbody radiation is very weak in this spectral band: about two orders of magnitude below that of the infrared band. Therefore the role of the detector technology is of ultimate importance to achieve sufficient sensitivity. In this paper we present results related to our technology relying on superconducting kinetic inductance detectors operating in a thermal (bolometric) mode. The detector technology is motivated by the fact that it is naturally suitable for scalable multiplexed readout systems, and operates with relatively simple cryogenics. We will review the basic concepts of the detectors, and provide experimental figures of merit. Furthermore, we will discuss the issues related to the scale-up of our detector technology into large 2D focal plane arrays.

The RAPID method for blood processing yields new insight in plasma concentrations and molecular forms of circulating gut peptides.

PubMed

Stengel, Andreas; Keire, David; Goebel, Miriam; Evilevitch, Lena; Wiggins, Brian; Taché, Yvette; Reeve, Joseph R

2009-11-01

The correct identification of circulating molecular forms and measurement of peptide levels in blood entails that the endocrine peptide being studied is stable and recovered in good yields during blood processing. However, it is not clear whether this is achieved in studies using standard blood processing. Therefore, we compared peptide concentration and form of 12 (125)I-labeled peptides using the standard procedure (EDTA-blood on ice) and a new method employing Reduced temperatures, Acidification, Protease inhibition, Isotopic exogenous controls, and Dilution (RAPID). During standard processing there was at least 80% loss for calcitonin-gene-related peptide and cholecystokinin-58 (CCK-58) and more than 35% loss for amylin, insulin, peptide YY forms (PYY((1-36)) and PYY((3-36))), and somatostatin-28. In contrast, the RAPID method significantly improved the recovery for 11 of 12 peptides (P < 0.05) and eliminated the breakdown of endocrine peptides occurring after standard processing as reflected in radically changed molecular forms for CCK-58, gastrin-releasing peptide, somatostatin-28, and ghrelin. For endogenous ghrelin, this led to an acyl/total ghrelin ratio of 1:5 instead of 1:19 by the standard method. These results show that the RAPID method enables accurate assessment of circulating gut peptide concentrations and forms such as CCK-58, acylated ghrelin, and somatostatin-28. Therefore, the RAPID method represents an efficacious means to detect circulating variations in peptide concentrations and form relevant to the understanding of physiological function of endocrine peptides.

[A rapid dialysis method for analysis of artificial sweeteners in food].

PubMed

Tahara, Shoichi; Fujiwara, Takushi; Yasui, Akiko; Hayafuji, Chieko; Kobayashi, Chigusa; Uematsu, Yoko

2014-01-01

A simple and rapid dialysis method was developed for the extraction and purification of four artificial sweeteners, namely, sodium saccharin (Sa), acesulfame potassium (AK), aspartame (APM), and dulcin (Du), which are present in various foods. Conventional dialysis uses a membrane dialysis tube approximately 15 cm in length and is carried out over many hours owing to the small membrane area and owing to inefficient mixing. In particular, processed cereal products such as cookies required treatment for 48 hours to obtain satisfactory recovery of the compounds. By increasing the tube length to 55 cm and introducing efficient mixing by inversion at half-hour intervals, the dialysis times of the four artificial sweeteners, spiked at 0.1 g/kg in the cookie, were shortened to 4 hours. Recovery yields of 88.9-103.2% were obtained by using the improved method, whereas recovery yields were low (65.5-82.0%) by the conventional method. Recovery yields (%) of Sa, AK, APM, and Du, spiked at 0.1 g/kg in various foods, were 91.6-100.1, 93.9-100.1, 86.7-100.0 and 88.7-104.7 using the improved method.

A case study of comparing radiometrically calibrated reflectance of an image mosaic from unmanned aerial system with that of a single image from manned aircraft over a same area

NASA Astrophysics Data System (ADS)

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

2017-05-01

Though sharing with many commonalities, one of the major differences between conventional high-altitude airborne remote sensing and low-altitude unmanned aerial system (UAS) based remote sensing is that the latter one has much smaller ground footprint for each image shot. To cover the same area on the ground, it requires the low-altitude UASbased platform to take many highly-overlapped images to produce a good mosaic, instead of just one or a few image shots by the high-altitude aerial platform. Such an UAS flight usually takes 10 to 30 minutes or even longer to complete; environmental lighting change during this time span cannot be ignored especially when spectral variations of various parts of a field are of interests. In this case study, we compared the visible reflectance of two aerial imagery - one generated from mosaicked UAS images, the other generated from a single image taken by a manned aircraft - over the same agricultural field to quantitatively evaluate their spectral variations caused by the different data acquisition strategies. Specifically, we (1) developed our customized ground calibration points (GCPs) and an associated radiometric calibration method for UAS data processing based on camera's sensitivity characteristics; (2) developed a basic comparison method for radiometrically calibrated data from the two aerial platforms based on regions of interests. We see this study as a starting point for a series of following studies to understand the environmental influence on UAS data and investigate the solutions to minimize such influence to ensure data quality.

Rapid presumptive identification of the Mycobacterium tuberculosis-bovis complex by radiometric determination of heat stable urease

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

Gandy, J.H.; Pruden, E.L.; Cox, F.R.

1983-12-01

Simple and rapid Bactec methodologies for the determination of neat (unaltered) and heat stable urease activity of mycobacteria are presented. Clinical isolates (63) and stock cultures (32)--consisting of: M. tuberculosis (19), M. bovis (5), M. kansasii (15), M. marinum (4), M. simiae (3), M. scrofulaceum (16), M. gordonae (6), M. szulgai (6), M. flavescens (1), M. gastri (1), M. intracellulare (6), M. fortuitum-chelonei complex (12), and M. smegmatis (1)--were tested for neat urease activity by Bactec radiometry. Mycobacterial isolates (50-100 mg wet weight) were incubated at 35 degrees C for 30 minutes with microCi14C-urea. Urease-positive mycobacteria gave Bactec growth indexmore » (GI) values greater than 100 units, whereas urease-negative species gave values less than 10 GI units. Eighty-three isolates possessing neat urease activity were heated at 80 degrees C for 30 minutes followed by incubation at 35 degrees C for 30 minutes with 1 microCi14C-urea. Mycobacterium tuberculosis-bovis complex demonstrated heat-stable urease activity (GI more than 130 units) and could be distinguished from mycobacteria other than tuberculosis (MOTT), which gave GI values equal to or less than 40 units.« less

Radiometric Quality of the MODIS Bands at 667 and 678nm

NASA Technical Reports Server (NTRS)

Meister, Gerhard; Franz, Bryan A.

2010-01-01

The MODIS instruments on Terra and Aqua were designed to allow the measurement of chlorophyll fluorescence effects over ocean. The retrieval algorithm is based on the difference between the water-leaving radiances at 667nm and 678nm. The water-leaving radiances at these wavelengths are usually very low relative to the top- of-atmosphere radiances. The high radiometric accuracy needed to retrieve the small fluorescence signal lead to a dual gain design for the 667 and 678nm bands. This paper discusses the benefits obtained from this design choice and provides justification for the use of only one set of gains for global processing of ocean color products. Noise characteristics of the two bands and their related products are compared to other products of bands from 412nm to 2130nm. The impact of polarization on the two bands is discussed. In addition, the impact of stray light on the two bands is compared to other MODIS bands.

Radiometric Quality of the MODIS Bands at 667 and 678nm

NASA Technical Reports Server (NTRS)

Meister, Gerhard; Franz, Bryan A.

2011-01-01

The MODIS instruments on Terra and Aqua were designed to allow the measurement of chlorophyll fluorescence effects over ocean. The retrieval algorithm is based on the difference between the water-leaving radiances at 667nm and 678nm. The water-leaving radiances at these wavelengths are usually very low relative to the top-of-atmosphere radiances. The high radiometric accuracy needed to retrieve the small fluorescence signal lead to a dual gain design for the 667 and 678nm bands. This paper discusses the benefits obtained from this design choice and provides justification for the use of only one set of gains for global processing of ocean color products. Noise characteristics of the two bands and their related products are compared to other products of bands from 412nm to 2130nm. The impact of polarization on the two bands is discussed. In addition, the impact of stray light on the two bands is compared to other MODIS bands.

Conventional Rapid Latex Agglutination in Estimation of von Willebrand Factor: Method Revisited and Potential Clinical Applications

PubMed Central

Che Hussin, Che Maraina

2014-01-01

Measurement of von Willebrand factor antigen (VWF : Ag) levels is usually performed in a specialised laboratory which limits its application in routine clinical practice. So far, no commercial rapid test kit is available for VWF : Ag estimation. This paper discusses the technical aspect of latex agglutination method which was established to suit the purpose of estimating von Willebrand factor (VWF) levels in the plasma sample. The latex agglutination test can be performed qualitatively and semiquantitatively. Reproducibility, stability, linearity, limit of detection, interference, and method comparison studies were conducted to evaluate the performance of this test. Semiquantitative latex agglutination test was strongly correlated with the reference immunoturbidimetric assay (Spearman's rho = 0.946, P < 0.001, n = 132). A substantial agreement (κ = 0.77) was found between qualitative latex agglutination test and the reference assay. Using the scoring system for the rapid latex test, no agglutination is with 0% VWF : Ag (control negative), 1+ reaction is equivalent to <20% VWF : Ag, and 4+ reaction indicates >150% VWF : Ag (when comparing with immunoturbidimetric assay). The findings from evaluation studies suggest that latex agglutination method is suitable to be used as a rapid test kit for the estimation of VWF : Ag levels in various clinical conditions associated with high levels and low levels of VWF : Ag. PMID:25759835

A Rapid and Efficient Screening Method for Antibacterial Compound-Producing Bacteria.

PubMed

Hettiarachchi, Sachithra; Lee, Su-Jin; Lee, Youngdeuk; Kwon, Young-Kyung; De Zoysa, Mahanama; Moon, Song; Jo, Eunyoung; Kim, Taeho; Kang, Do-Hyung; Heo, Soo-Jin; Oh, Chulhong

2017-08-28

Antibacterial compounds are widely used in the treatment of human and animal diseases. The overuse of antibiotics has led to a rapid rise in the prevalence of drug-resistant bacteria, making the development of new antibacterial compounds essential. This study focused on developing a fast and easy method for identifying marine bacteria that produce antibiotic compounds. Eight randomly selected marine target bacterial species ( Agrococcus terreus, Bacillus algicola, Mesoflavibacter zeaxanthinifaciens, Pseudoalteromonas flavipulchra, P. peptidolytica, P. piscicida, P. rubra , and Zunongwangia atlantica ) were tested for production of antibacterial compounds against four strains of test bacteria ( B. cereus, B. subtilis, Halomonas smyrnensis , and Vibrio alginolyticus ). Colony picking was used as the primary screening method. Clear zones were observed around colonies of P. flavipulchra, P. peptidolytica, P. piscicida , and P. rubra tested against B. cereus, B. subtilis , and H. smyrnensis . The efficiency of colony scraping and broth culture methods for antimicrobial compound extraction was also compared using a disk diffusion assay. P. peptidolytica, P. piscicida , and P. rubra showed antagonistic activity against H. smyrnensis, B. cereus , and B. subtilis , respectively, only in the colony scraping method. Our results show that colony picking and colony scraping are effective, quick, and easy methods of screening for antibacterial compound-producing bacteria.

Cochrane Rapid Reviews Methods Group to play a leading role in guiding the production of informed high-quality, timely research evidence syntheses.

PubMed

Garritty, Chantelle; Stevens, Adrienne; Gartlehner, Gerald; King, Valerie; Kamel, Chris

2016-10-28

Policymakers and healthcare stakeholders are increasingly seeking evidence to inform the policymaking process, and often use existing or commissioned systematic reviews to inform decisions. However, the methodologies that make systematic reviews authoritative take time, typically 1 to 2 years to complete. Outside the traditional SR timeline, "rapid reviews" have emerged as an efficient tool to get evidence to decision-makers more quickly. However, the use of rapid reviews does present challenges. To date, there has been limited published empirical information about this approach to compiling evidence. Thus, it remains a poorly understood and ill-defined set of diverse methodologies with various labels. In recent years, the need to further explore rapid review methods, characteristics, and their use has been recognized by a growing network of healthcare researchers, policymakers, and organizations, several with ties to Cochrane, which is recognized as representing an international gold standard for high-quality, systematic reviews. In this commentary, we introduce the newly established Cochrane Rapid Reviews Methods Group developed to play a leading role in guiding the production of rapid reviews given they are increasingly employed as a research synthesis tool to support timely evidence-informed decision-making. We discuss how the group was formed and outline the group's structure and remit. We also discuss the need to establish a more robust evidence base for rapid reviews in the published literature, and the importance of promoting registration of rapid review protocols in an effort to promote efficiency and transparency in research. As with standard systematic reviews, the core principles of evidence-based synthesis should apply to rapid reviews in order to minimize bias to the extent possible. The Cochrane Rapid Reviews Methods Group will serve to establish a network of rapid review stakeholders and provide a forum for discussion and training. By facilitating

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.

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

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.

A Rapid and Improved Method to Generate Recombinant Dengue Virus Vaccine Candidates

PubMed Central

Govindarajan, Dhanasekaran; Guan, Liming; Meschino, Steven; Fridman, Arthur; Bagchi, Ansu; Pak, Irene; ter Meulen, Jan; Casimiro, Danilo R.; Bett, Andrew J.

2016-01-01

Dengue is one of the most important mosquito-borne infections accounting for severe morbidity and mortality worldwide. Recently, the tetravalent chimeric live attenuated Dengue vaccine Dengvaxia® was approved for use in several dengue endemic countries. In general, live attenuated vaccines (LAV) are very efficacious and offer long-lasting immunity against virus-induced disease. Rationally designed LAVs can be generated through reverse genetics technology, a method of generating infectious recombinant viruses from full length cDNA contained in bacterial plasmids. In vitro transcribed (IVT) viral RNA from these infectious clones is transfected into susceptible cells to generate recombinant virus. However, the generation of full-length dengue virus cDNA clones can be difficult due to the genetic instability of viral sequences in bacterial plasmids. To circumvent the need for a single plasmid containing a full length cDNA, in vitro ligation of two or three cDNA fragments contained in separate plasmids can be used to generate a full-length dengue viral cDNA template. However, in vitro ligation of multiple fragments often yields low quality template for IVT reactions, resulting in inconsistent low yield RNA. These technical difficulties make recombinant virus recovery less efficient. In this study, we describe a simple, rapid and efficient method of using LONG-PCR to recover recombinant chimeric Yellow fever dengue (CYD) viruses as potential dengue vaccine candidates. Using this method, we were able to efficiently generate several viable recombinant viruses without introducing any artificial mutations into the viral genomes. We believe that the techniques reported here will enable rapid and efficient recovery of recombinant flaviviruses for evaluation as vaccine candidates and, be applicable to the recovery of other RNA viruses. PMID:27008550

A Rapid and Improved Method to Generate Recombinant Dengue Virus Vaccine Candidates.

PubMed

Govindarajan, Dhanasekaran; Guan, Liming; Meschino, Steven; Fridman, Arthur; Bagchi, Ansu; Pak, Irene; ter Meulen, Jan; Casimiro, Danilo R; Bett, Andrew J

2016-01-01

Dengue is one of the most important mosquito-borne infections accounting for severe morbidity and mortality worldwide. Recently, the tetravalent chimeric live attenuated Dengue vaccine Dengvaxia® was approved for use in several dengue endemic countries. In general, live attenuated vaccines (LAV) are very efficacious and offer long-lasting immunity against virus-induced disease. Rationally designed LAVs can be generated through reverse genetics technology, a method of generating infectious recombinant viruses from full length cDNA contained in bacterial plasmids. In vitro transcribed (IVT) viral RNA from these infectious clones is transfected into susceptible cells to generate recombinant virus. However, the generation of full-length dengue virus cDNA clones can be difficult due to the genetic instability of viral sequences in bacterial plasmids. To circumvent the need for a single plasmid containing a full length cDNA, in vitro ligation of two or three cDNA fragments contained in separate plasmids can be used to generate a full-length dengue viral cDNA template. However, in vitro ligation of multiple fragments often yields low quality template for IVT reactions, resulting in inconsistent low yield RNA. These technical difficulties make recombinant virus recovery less efficient. In this study, we describe a simple, rapid and efficient method of using LONG-PCR to recover recombinant chimeric Yellow fever dengue (CYD) viruses as potential dengue vaccine candidates. Using this method, we were able to efficiently generate several viable recombinant viruses without introducing any artificial mutations into the viral genomes. We believe that the techniques reported here will enable rapid and efficient recovery of recombinant flaviviruses for evaluation as vaccine candidates and, be applicable to the recovery of other RNA viruses.

a Method for Preview Vibration Control of Systems Having Forcing Inputs and Rapidly-Switched Dampers

NASA Astrophysics Data System (ADS)

ElBeheiry, E. M.

1998-07-01

In a variety of applications, especially in large scale dynamic systems, the mechanization of different vibration control elements in different locations would be decided by limitations placed on the modal vibration of the system and the inherent dynamic coupling between its modes. Also, the quality of vibration control to the economy of producing the whole system would be another trade-off leading to a mix of passive, active and semi-active vibration control elements in one system. This termactiveis limited to externally powered vibration control inputs and the termsemi-activeis limited to rapidly switched dampers. In this article, an optimal preview control method is developed for application to dynamic systems having active and semi-active vibration control elements mechanized at different locations in one system. The system is then a piecewise (bilinear) controller in which two independent sets of control inputs appear additively and multiplicatively. Calculus of variations along with the Hamiltonian approach are employed for the derivation of this method. In essence, it requires the active elements to be ideal force generators and the switched dampers to have the property of on-line variation of the damping characteristics to pre-determined limits. As the dampers switch during operation the whole system's structure differs, and then values of the active forcing inputs are adapted to match these rapid changes. Strictly speaking, each rapidly switched damper has pre-known upper and lower damping levels and it can take on any in-between value. This in-between value is to be determined by the method as long as the damper tracks a pre-known fully active control demand. In every damping state of each semi-active damper the method provides the optimal matching values of the active forcing inputs. The method is shown to have the feature of solving simple standard matrix equations to obtain closed form solutions. A comprehensive 9-DOF tractor semi-trailer model is used

A novel rapid and reproducible flow cytometric method for optimization of transfection efficiency in cells

PubMed Central

Homann, Stefanie; Hofmann, Christian; Gorin, Aleksandr M.; Nguyen, Huy Cong Xuan; Huynh, Diana; Hamid, Phillip; Maithel, Neil; Yacoubian, Vahe; Mu, Wenli; Kossyvakis, Athanasios; Sen Roy, Shubhendu; Yang, Otto Orlean

2017-01-01

Transfection is one of the most frequently used techniques in molecular biology that is also applicable for gene therapy studies in humans. One of the biggest challenges to investigate the protein function and interaction in gene therapy studies is to have reliable monospecific detection reagents, particularly antibodies, for all human gene products. Thus, a reliable method that can optimize transfection efficiency based on not only expression of the target protein of interest but also the uptake of the nucleic acid plasmid, can be an important tool in molecular biology. Here, we present a simple, rapid and robust flow cytometric method that can be used as a tool to optimize transfection efficiency at the single cell level while overcoming limitations of prior established methods that quantify transfection efficiency. By using optimized ratios of transfection reagent and a nucleic acid (DNA or RNA) vector directly labeled with a fluorochrome, this method can be used as a tool to simultaneously quantify cellular toxicity of different transfection reagents, the amount of nucleic acid plasmid that cells have taken up during transfection as well as the amount of the encoded expressed protein. Finally, we demonstrate that this method is reproducible, can be standardized and can reliably and rapidly quantify transfection efficiency, reducing assay costs and increasing throughput while increasing data robustness. PMID:28863132

Comparing different methods for fast screening of microbiological quality of beach sand aimed at rapid-response remediation.

PubMed

Testolin, Renan C; Almeida, Tito C M; Polette, Marcus; Branco, Joaquim O; Fischer, Larissa L; Niero, Guilherme; Poyer-Radetski, Gabriel; Silva, Valéria C; Somensi, Cleder A; Corrêa, Albertina X R; Corrêa, Rogério; Rörig, Leonardo R; Itokazu, Ana Gabriela; Férard, Jean-François; Cotelle, Sylvie; Radetski, Claudemir M

2017-05-15

There is scientific evidence that beach sands are a significant contributor to the pathogen load to which visitors are exposed. To develop beach quality guidelines all beach zones must be included in microbiological evaluations, but monitoring methods for beach sand quality are relatively longstanding, expensive, laborious and require moderate laboratory infrastructure. This paper aimed to evaluate the microorganism activity in different beach zones applying and comparing a classical method of membrane filtration (MF) with two colorimetric screening methods based on fluorescein (FDA) and tetrazolium (TTC) salt biotransformation to evaluate a new rapid and low-cost method for beach sand microbiological contamination assessments. The colorimetric results can help beach managers to evaluate rapidly and at low cost the microbiological quality of different beach zones in order to decide whether remedial actions need to be adopted to prevent exposure of the public to microbes due to beach sand and/or water contamination. Copyright © 2017. Published by Elsevier Ltd.

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.

Rapid methods for the isolation of actinides Sr, Tc and Po from raw urine.