WorldWideScience

Sample records for hand-held spectral radiometer

  1. Cost effective spectral sensor solutions for hand held and field applications

    Science.gov (United States)

    Reetz, Edgar; Correns, Martin; Notni, Gunther

    2015-05-01

    Optical spectroscopy is without doubt one of the most important non-contact measurement principles. It is used in a wide range of applications from bio-medical to industrial fields. One recent trend is to miniaturize spectral sensors to address new areas of application. The most common spectral sensor type is based on diffraction gratings, while other types are based on micro mechanical systems (MEMS) or filter technologies. The authors represent the opinion that there is a potentially wide spread field of applications for spectrometers, but the market limits the range of applications since they cannot keep up with targeted cost requirements for consumer products. The present article explains an alternative approach for miniature multichannel spectrometer to enhance robustness for hand held field applications at a cost efficient price point.

  2. Hand-held medical robots.

    Science.gov (United States)

    Payne, Christopher J; Yang, Guang-Zhong

    2014-08-01

    Medical robots have evolved from autonomous systems to tele-operated platforms and mechanically-grounded, cooperatively-controlled robots. Whilst these approaches have seen both commercial and clinical success, uptake of these robots remains moderate because of their high cost, large physical footprint and long setup times. More recently, researchers have moved toward developing hand-held robots that are completely ungrounded and manipulated by surgeons in free space, in a similar manner to how conventional instruments are handled. These devices provide specific functions that assist the surgeon in accomplishing tasks that are otherwise challenging with manual manipulation. Hand-held robots have the advantages of being compact and easily integrated into the normal surgical workflow since there is typically little or no setup time. Hand-held devices can also have a significantly reduced cost to healthcare providers as they do not necessitate the complex, multi degree-of-freedom linkages that grounded robots require. However, the development of such devices is faced with many technical challenges, including miniaturization, cost and sterility, control stability, inertial and gravity compensation and robust instrument tracking. This review presents the emerging technical trends in hand-held medical robots and future development opportunities for promoting their wider clinical uptake.

  3. Rotating shadowband radiometer development and analysis of spectral shortwave data

    Energy Technology Data Exchange (ETDEWEB)

    Michalsky, J.; Harrison, L.; Min, Q. [State Univ. of New York, Albany, NY (United States)] [and others

    1996-04-01

    Our goals in the Atmospheric Radiation Measurement (ARM) Program are improved measurements of spectral shortwave radiation and improved techniques for the retrieval of climatologically sensitive parameters. The multifilter rotating shadowband radiometer (MFRSR) that was developed during the first years of the ARM program has become a workhorse at the Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site, and it is widely deployed in other climate programs. We have spent most of our effort this year developing techniques to retrieve column aerosol, water vapor, and ozone from direct beam spectral measurements of the MFRSR. Additionally, we have had some success in calculating shortwave surface diffuse spectral irradiance. Using the surface albedo and the global irradiance, we have calculated cloud optical depths. From cloud optical depth and liquid water measured with the microwave radiometer, we have calculated effective liquid cloud particle radii. The rest of the text will provide some detail regarding each of these efforts.

  4. Hand-held and automated breast ultrasound

    International Nuclear Information System (INIS)

    Bassett, L.W.; Gold, R.H.; Kimme-Smith, C.

    1985-01-01

    The book is a guide for physicians and technologists who use US as an adjunct to mammography; it carefully outlines the pros and cons of US of the breast and its role in the diagnosis of benign and malignant diseases. After an introduction that discusses the philosophy of breast US, the chapters cover the physics of US and instrumentation (both hand-held transducers as well as automated water path scanners), then proceed to a discussion of the normal breast. Sections on benign disorders, malignant lesions, and pitfalls of diagnosis are followed by quiz cases

  5. 30 CFR 57.12033 - Hand-held electric tools.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hand-held electric tools. 57.12033 Section 57.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12033 Hand-held electric tools. Hand-held electric tools shall not be...

  6. 30 CFR 56.12033 - Hand-held electric tools.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hand-held electric tools. 56.12033 Section 56.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL....12033 Hand-held electric tools. Hand-held electric tools shall not be operated at high potential...

  7. Hand-held optical fuel pin scanner

    International Nuclear Information System (INIS)

    Kirchner, T.L.; Powers, H.G.

    1987-01-01

    A portable, hand-held apparatus is described for optically scanning indicia imprinted about a planar end face of an article having an outer wall surface, the apparatus comprising: a supporting frame; light detector means fixed to the frame for digitizing light patterns directed thereto; indexing means on the frame for engaging the planar end face and locating the end face in a preselected focal plane on the frame. The indexing means has an inner wall surface complementary to the article wall surface for disposition thereabout and terminates in an end portion beyond the planar end face. The inner wall surface has a radially inwardly extending shoulder spaced from the end portion and engageable with the planar end face; light means directed onto the preselected focal plane; optical means mounted on the frame about a central axis, the optical means being optically interposed between the indexing means and the light detector means for directing reflected light from the preselected focal plane to the light detector means and including a dove prism centrally aligned along the central axis; and means for selectively rotating the dove prism relative to the frame about the central axis to thereby rotate the image from the focal plane as transmitted to the light detector means

  8. The availability of relatively cheap hand-held Global Positioning ...

    African Journals Online (AJOL)

    spamer

    conditions, so the approach failed to produce results ... Hand-held Global Positioning System (GPS) receivers provide opportunities for detailed and rapid mapping of features ..... TICKELL, W. L. N. 1968 — The biology of the great albatrosses,.

  9. An Intelligent Hand-Held Microsurgical Instrument for Improved Accuracy

    National Research Council Canada - National Science Library

    Ang, Wei

    2001-01-01

    This paper presents the development and initial experimental results of the first prototype of Micron, an active hand-held instrument to sense and compensate physiological tremor and other unwanted...

  10. Plans for Hand-Held/Portable Oil Assessment Devices

    National Research Council Canada - National Science Library

    Urbansky, Edward

    2005-01-01

    At the request of the U.S. Army Oil Analysis Program, the JOAP TSC conducted a market study, assembled a plan of action, and prepared a worksheet for the evaluation of portable or hand-held oil assessment devices...

  11. Epilepsy Forewarning Using A Hand-Held Device

    Energy Technology Data Exchange (ETDEWEB)

    Hively, LM

    2005-02-21

    Over the last decade, ORNL has developed and patented a novel approach for forewarning of a large variety of machine and biomedical events. The present implementation uses desktop computers to analyze archival data. This report describes the next logical step in this effort, namely use of a hand-held device for the analysis.

  12. New portable hand-held radiation instruments for measurements and monitoring

    International Nuclear Information System (INIS)

    Fehlau, P.E.

    1987-01-01

    Hand-held radiation monitors are often used to search pedestrians and motor vehicles for special nuclear material (SNM) as part of a physical protection plan for nuclear materials. Recently, the Los Alamos Advanced Nuclear Technology group has commercialized an improved hand-held monitor that can be used for both physical-protection monitoring and verification measurements in nuclear material control and waste management. The new monitoring instruments are smaller and lighter; operate much longer on a battery charge; are available with NaI(Tl) or neutron and gamma-ray sensitive plastic scintillation detectors; and are less expensive than other comparable instruments. They also have a second operating mode for making precise measurements over counting times as long as 99 s. This mode permits making basic verification measurements that may be needed before transporting nuclear material or waste outside protected areas. Improved verification measurements can be made with a second new hand-held instrument that has a stabilized detector and three separate gamma-ray energy windows to obtain spectral information for SNM quantity, enrichment, or material-type verification

  13. Hand-held electronic data collection and procedure environment

    International Nuclear Information System (INIS)

    Kennedy, E.; Doniz, K.

    1996-01-01

    As part of a CANDU Owners Group project, AECL has developed a hand-held electronic data collection and procedure environment. Integral to this environment is the C omputerized Procedure Engine . The development of the CPE allows operators, maintainers, and technical support staff to execute virtually any type of station procedure on a general-purpose PC-compatible hand-held computer. There are several advantages to using the computerized procedures: less paper use and handling, reduction in human error, reduction in rework in the field, an increase in procedural compliance, and immediate availability of data to download to databases and plant information systems. The paper describes: the advantages of using computerized procedures, why early forms of computerized procedures were inadequate, the features that the C omputerized Procedure Engine o ffers to the user, the streamlined life cycle of a computerized procedure, and field experience. The paper concludes that computerized procedures are ready for pilot applications at stations. (author)

  14. Interactive topology optimization on hand-held devices

    DEFF Research Database (Denmark)

    Aage, Niels; Nobel-Jørgensen, Morten; Andreasen, Casper Schousboe

    2013-01-01

    This paper presents an interactive topology optimization application designed for hand-held devices running iOS or Android. The TopOpt app solves the 2D minimum compliance problem with interactive control of load and support positions as well as volume fraction. Thus, it is possible to change......OS devices from the Apple App Store, at Google Play for the Android platform, and a web-version can be run from www.topopt.dtu.dk....

  15. Exploring field-of-view non-uniformities produced by a hand-held spectroradiometer

    Directory of Open Access Journals (Sweden)

    Tamir Caras

    2011-01-01

    Full Text Available The shape of a spectroradiometer’s field of view (FOV affects the way spectral measurements are acquired. Knowing this property is a prerequisite for the correct use of the spectrometer. If the substrate is heterogeneous, the ability to accurately know what is being measured depends on knowing the FOV location, shape, spectral and spatial sensitivity. The GER1500 is a hand-held spectrometer with a fixed lens light entry slit and has a laser guide that allows control over the target by positioning the entire unit. In the current study, the FOV of the GER1500 was mapped and analysed. The spectral and spatial non-uniformities of the FOV were examined and were found to be spectrally independent. The relationship between the FOV and the built-in laser guide was tested and found to have a linear displacement dependent on the distance to the target. This allows an accurate prediction of the actual FOV position. A correction method to improve the agreement between the expected and measured reflectance over heterogeneous targets was developed and validated. The methods described are applicable and may be of use with other hand-held spectroradiometers.

  16. A hand-held robotic device for peripheral intravenous catheterization.

    Science.gov (United States)

    Cheng, Zhuoqi; Davies, Brian L; Caldwell, Darwin G; Barresi, Giacinto; Xu, Qinqi; Mattos, Leonardo S

    2017-12-01

    Intravenous catheterization is frequently required for numerous medical treatments. However, this process is characterized by a high failure rate, especially when performed on difficult patients such as newborns and infants. Very young patients have small veins, and that increases the chances of accidentally puncturing the catheterization needle directly through them. In this article, we present the design, development and experimental evaluation of a novel hand-held robotic device for improving the process of peripheral intravenous catheterization by facilitating the needle insertion procedure. To our knowledge, this design is the first hand-held robotic device for assisting in the catheterization insertion task. Compared to the other available technologies, it has several unique advantages such as being compact, low-cost and able to reliably detect venipuncture. The system is equipped with an electrical impedance sensor at the tip of the catheterization needle, which provides real-time measurements used to supervise and control the catheter insertion process. This allows the robotic system to precisely position the needle within the lumen of the target vein, leading to enhanced catheterization success rate. Experiments conducted to evaluate the device demonstrated that it is also effective to deskill the task. Naïve subjects achieved an average catheterization success rate of 88% on a 1.5 mm phantom vessel with the robotic device versus 12% with the traditional unassisted system. The results of this work prove the feasibility of a hand-held assistive robotic device for intravenous catheterization and show that such device has the potential to greatly improve the success rate of these difficult operations.

  17. Adaptive RF front-ends for hand-held applications

    CERN Document Server

    van Bezooijen, Andre; van Roermund, Arthur

    2010-01-01

    The RF front-end - antenna combination is a vital part of a mobile phone because its performance is very relevant to the link quality between hand-set and cellular network base-stations. The RF front-end performance suffers from changes in operating environment, like hand-effects, that are often unpredictable. ""Adaptive RF Front-Ends for Hand-Held Applications"" presents an analysis on the impact of fluctuating environmental parameters. In order to overcome undesired behavior two different adaptive control methods are treated that make RF frond-ends more resilient: adaptive impedance control,

  18. Development of dual sensor hand-held detector

    Science.gov (United States)

    Sezgin, Mehmet

    2010-04-01

    In this paper hand-held dual sensor detector development requirements are considered dedicated to buried object detection. Design characteristics of such a system are categorized and listed. Hardware and software structures, ergonomics, user interface, environmental and EMC/EMI tests to be applied and performance test issues are studied. Main properties of the developed system (SEZER) are presented, which contains Metal Detector (MD) and Ground Penetrating Radar (GPR). The realized system has ergonomic structure and can detect both metallic and non-metallic buried objects. Moreover classification of target is possible if it was defined to the signal processing software in learning phase.

  19. A hand-held beta imaging probe for FDG.

    Science.gov (United States)

    Singh, Bipin; Stack, Brendan C; Thacker, Samta; Gaysinskiy, Valeriy; Bartel, Twyla; Lowe, Val; Cool, Steven; Entine, Gerald; Nagarkar, Vivek

    2013-04-01

    Advances in radiopharmaceuticals and clinical understanding have escalated the use of intraoperative gamma probes in surgery. However, most probes on the market are non-imaging gamma probes that suffer from the lack of ancillary information of the surveyed tissue area. We have developed a novel, hand-held digital Imaging Beta Probe™ (IBP™) to be used in surgery in conjunction with beta-emitting radiopharmaceuticals such as (18)FDG, (131)I and (32)P for real-time imaging of a surveyed area with higher spatial resolution and sensitivity and greater convenience than existing instruments. We describe the design and validation of a hand-held beta probe intended to be used as a visual mapping device to locate and confirm excision of (18)FDG-avid primary tumors and metastases in an animal model. We have demonstrated a device which can generate beta images from (18)FDG avid lesions in an animal model. It is feasible to image beta irradiation in animal models of cancer given (18)FDG. This technology may be applied to clinical mapping of tumors and/or their metastases in the operating room. Visual image depiction of malignancy may aid the surgeon in localization and excision of lesions of interest.

  20. Measuring thyroid uptake with hand-held radiation monitors

    International Nuclear Information System (INIS)

    Deschamps, M.

    1987-04-01

    With the use of Iodine 123, 125 and 131 and some compounds of Technetium-99 m, a fraction of the isotopes can be trapped in the thyroid of the technicians. We used the hand-held radiation contamination or survey meters of the nine (9) Nuclear medicine departments we visited to see if they were adequate for the evaluation of thyroid uptake of the users. Measurements on a neck-phanton helped us to determine a minimum detectable activity for each isotope. We were then able to check if the measurements of investigations and action levels were possible. None of the hand-held radiation monitors are completely satisfactory for the measure of thyroid uptake of the user. We discuss a class of equipment capable of measuring radiation emissions at the investigation level. Measurement at the action level is possible with meters having scintillation or proportional probes but none of them permits the discrimination in energy required for a quantitative evaluation of the radioisotopes used

  1. Hand held data collection and monitoring system for nuclear facilities

    Science.gov (United States)

    Brayton, D.D.; Scharold, P.G.; Thornton, M.W.; Marquez, D.L.

    1999-01-26

    Apparatus and method is disclosed for a data collection and monitoring system that utilizes a pen based hand held computer unit which has contained therein interaction software that allows the user to review maintenance procedures, collect data, compare data with historical trends and safety limits, and input new information at various collection sites. The system has a means to allow automatic transfer of the collected data to a main computer data base for further review, reporting, and distribution purposes and uploading updated collection and maintenance procedures. The hand held computer has a running to-do list so sample collection and other general tasks, such as housekeeping are automatically scheduled for timely completion. A done list helps users to keep track of all completed tasks. The built-in check list assures that work process will meet the applicable processes and procedures. Users can hand write comments or drawings with an electronic pen that allows the users to directly interface information on the screen. 15 figs.

  2. Hand held data collection and monitoring system for nuclear facilities

    International Nuclear Information System (INIS)

    Brayton, D.D.; Scharold, P.G.; Thornton, M.W.; Marquez, D.L.

    1999-01-01

    Apparatus and method is disclosed for a data collection and monitoring system that utilizes a pen based hand held computer unit which has contained therein interaction software that allows the user to review maintenance procedures, collect data, compare data with historical trends and safety limits, and input new information at various collection sites. The system has a means to allow automatic transfer of the collected data to a main computer data base for further review, reporting, and distribution purposes and uploading updated collection and maintenance procedures. The hand held computer has a running to-do list so sample collection and other general tasks, such as housekeeping are automatically scheduled for timely completion. A done list helps users to keep track of all completed tasks. The built-in check list assures that work process will meet the applicable processes and procedures. Users can hand write comments or drawings with an electronic pen that allows the users to directly interface information on the screen. 15 figs

  3. Hand-held spectrophotometer design for textile fabrics

    Science.gov (United States)

    Böcekçi, Veysel Gökhan; Yıldız, Kazım

    2017-09-01

    In this study, a hand-held spectrophotometer was designed by taking advantage of the developments in modern optoelectronic technology. Spectrophotometer devices are used to determine the color information from the optic properties of the materials. As an alternative to a desktop spectrophotometer device we have implemented, it is the first prototype, low cost and portable. The prototype model designed for the textile industry can detect the color tone of any fabric. The prototype model consists of optic sensor, processor, display floors. According to the color applied on the optic sensor, it produces special frequency information on its output at that color value. In Arduino type processor, the frequency information is evaluated by the program we have written and the color tone information between 0-255 ton is decided and displayed on the screen.

  4. Comparative Geometrical Investigations of Hand-Held Scanning Systems

    Science.gov (United States)

    Kersten, T. P.; Przybilla, H.-J.; Lindstaedt, M.; Tschirschwitz, F.; Misgaiski-Hass, M.

    2016-06-01

    An increasing number of hand-held scanning systems by different manufacturers are becoming available on the market. However, their geometrical performance is little-known to many users. Therefore the Laboratory for Photogrammetry & Laser Scanning of the HafenCity University Hamburg has carried out geometrical accuracy tests with the following systems in co-operation with the Bochum University of Applied Sciences (Laboratory for Photogrammetry) as well as the Humboldt University in Berlin (Institute for Computer Science): DOTProduct DPI-7, Artec Spider, Mantis Vision F5 SR, Kinect v1 + v2, Structure Sensor and Google's Project Tango. In the framework of these comparative investigations geometrically stable reference bodies were used. The appropriate reference data were acquired by measurement with two structured light projection systems (AICON smartSCAN and GOM ATOS I 2M). The comprehensive test results of the different test scenarios are presented and critically discussed in this contribution.

  5. COMPARATIVE GEOMETRICAL INVESTIGATIONS OF HAND-HELD SCANNING SYSTEMS

    Directory of Open Access Journals (Sweden)

    T. P. Kersten

    2016-06-01

    Full Text Available An increasing number of hand-held scanning systems by different manufacturers are becoming available on the market. However, their geometrical performance is little-known to many users. Therefore the Laboratory for Photogrammetry & Laser Scanning of the HafenCity University Hamburg has carried out geometrical accuracy tests with the following systems in co-operation with the Bochum University of Applied Sciences (Laboratory for Photogrammetry as well as the Humboldt University in Berlin (Institute for Computer Science: DOTProduct DPI-7, Artec Spider, Mantis Vision F5 SR, Kinect v1 + v2, Structure Sensor and Google’s Project Tango. In the framework of these comparative investigations geometrically stable reference bodies were used. The appropriate reference data were acquired by measurement with two structured light projection systems (AICON smartSCAN and GOM ATOS I 2M. The comprehensive test results of the different test scenarios are presented and critically discussed in this contribution.

  6. Algorithms for a hand-held miniature x-ray fluorescence analytical instrument

    International Nuclear Information System (INIS)

    Elam, W.T.; Newman, D.; Ziemba, F.

    1998-01-01

    The purpose of this joint program was to provide technical assistance with the development of a Miniature X-ray Fluorescence (XRF) Analytical Instrument. This new XRF instrument is designed to overcome the weaknesses of spectrometers commercially available at the present time. Currently available XRF spectrometers (for a complete list see reference 1) convert spectral information to sample composition using the influence coefficients technique or the fundamental parameters method. They require either a standard sample with composition relatively close to the unknown or a detailed knowledge of the sample matrix. They also require a highly-trained operator and the results often depend on the capabilities of the operator. In addition, almost all existing field-portable, hand-held instruments use radioactive sources for excitation. Regulatory limits on such sources restrict them such that they can only provide relatively weak excitation. This limits all current hand-held XRF instruments to poor detection limits and/or long data collection times, in addition to the licensing requirements and disposal problems for radioactive sources. The new XRF instrument was developed jointly by Quantrad Sensor, Inc., the Naval Research Laboratory (NRL), and the Department of Energy (DOE). This report describes the analysis algorithms developed by NRL for the new instrument and the software which embodies them

  7. Technical progress report: Completion of spectral rotating shadowband radiometers and analysis of atmospheric radiation measurement spectral shortwave data

    Energy Technology Data Exchange (ETDEWEB)

    Michalsky, J.; Harrison, L. [State Univ. of New York, Albany, NY (United States)

    1996-04-01

    Our goal in the Atmospheric Radiation Measurement (ARM) Program is the improvement of radiation models used in general circulation models (GCMs), especially in the shortwave, (1) by providing improved shortwave radiometric measurements for the testing of models and (2) by developing methods for retrieving climatologically sensitive parameters that serve as input to shortwave and longwave models. At the Atmospheric Sciences Research Center (ASRC) in Albany, New York, we are acquiring downwelling direct and diffuse spectral irradiance, at six wavelengths, plus downwelling broadband longwave, and upwelling and downwelling broadband shortwave irradiances that we combine with National Weather Service surface and upper air data from the Albany airport as a test data set for ARM modelers. We have also developed algorithms to improve shortwave measurements made at the Southern Great Plains (SGP) ARM site by standard thermopile instruments and by the multifilter rotating shadowband radiometer (MFRSR) based on these Albany data sets. Much time has been spent developing techniques to retrieve column aerosol, water vapor, and ozone from the direct beam spectral measurements of the MFRSR. Additionally, we have had success in calculating shortwave surface albedo and aerosol optical depth from the ratio of direct to diffuse spectral reflectance.

  8. A linear model to predict with a multi-spectral radiometer the amount of nitrogen in winter wheat

    NARCIS (Netherlands)

    Reyniers, M.; Walvoort, D.J.J.; Baardemaaker, De J.

    2006-01-01

    The objective was to develop an optimal vegetation index (VIopt) to predict with a multi-spectral radiometer nitrogen in wheat crop (kg[N] ha-1). Optimality means that nitrogen in the crop can be measured accurately in the field during the growing season. It also means that the measurements are

  9. Attentionally splitting the mass distribution of hand-held rods.

    Science.gov (United States)

    Burton, G; Turvey, M T

    1991-08-01

    Two experiments on the length-perception capabilities of effortful or dynamic touch differed only in terms of what the subject intended to perceive, while experimental conditions and apparatus were held constant. In each trial, a visually occluded rod was held as still as possible by the subject at an intermediate position. For two thirds of the trials, a weight was attached to the rod above or below the hand. In Experiment 1, in which the subject's task was to perceive the distance reachable with the portion of the rod forward of the hand, perceived extent was a function of the first moment of the mass distribution associated with the forward portion of the rod, and indifferent to the first moment of the entire rod. In Experiment 2, in which the task was to perceive the distance reachable with the entire rod if it was held at an end, the pattern of results was reversed. These results indicate the capability of selective sensitivity to different aspects of a hand-held object's mass distribution, without the possibility of differential exploration specific to these two tasks. Results are discussed in relation to possible roles of differential information, intention, and self-organization in the explanations of selective perceptual abilities.

  10. Portable Hand-Held Electrochemical Sensor for the Transuranics

    Energy Technology Data Exchange (ETDEWEB)

    Dale D. Russell, William B. Knowlton, Ph.D.; Russel Hertzog, Ph.D

    2005-11-25

    sensitive detector for uranium. Millimeter scale electrodes, operated by a hand-held instrument assembled in this lab and operated in the voltammetric mode, were transported to the DOE-Nevada test site (Las Vegas, NV) where field detection and quantitation of plutonium, uranium, and a mixture of these two elements was also demonstrated. Several probe designs were prepared, built and tested including probes with movable protective windows. A miniature, battery powered potentiostat was designed, built and demonstrated for use in a hand-held field portable instrument. This work was performed largely by undergraduates who gained valuable research experience, and many of them have continued on to graduate schools. In addition, they all gained exposure to and appreciation for national security research, in particular non-proliferation research. Four graduate students participated and one earned the MS degree on this project.

  11. Direction-Sensitive Hand-Held Gamma-Ray Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Mukhopadhyay, S.

    2012-10-04

    A novel, light-weight, hand-held gamma-ray detector with directional sensitivity is being designed. The detector uses a set of multiple rings around two cylindrical surfaces, which provides precise location of two interaction points on two concentric cylindrical planes, wherefrom the source location can be traced back by back projection and/or Compton imaging technique. The detectors are 2.0 × 2.0 mm europium-doped strontium iodide (SrI2:Eu2+) crystals, whose light output has been measured to exceed 120,000 photons/MeV, making it one of the brightest scintillators in existence. The crystal’s energy resolution, less than 3% at 662 keV, is also excellent, and the response is highly linear over a wide range of gamma-ray energies. The emission of SrI2:Eu2+ is well matched to both photo-multiplier tubes and blue-enhanced silicon photodiodes. The solid-state photomultipliers used in this design (each 2.0 × 2.0 mm) are arrays of active pixel sensors (avalanche photodiodes driven beyond their breakdown voltage in reverse bias); each pixel acts as a binary photon detector, and their summed output is an analog representation of the total photon energy, while the individual pixel accurately defines the point of interaction. A simple back-projection algorithm involving cone-surface mapping is being modeled. The back projection for an event cone is a conical surface defining the possible location of the source. The cone axis is the straight line passing through the first and second interaction points.

  12. Quantifying seasonal dynamics of canopy structure and function using inexpensive narrowband spectral radiometers

    Science.gov (United States)

    Vierling, L. A.; Garrity, S. R.; Campbell, G.; Coops, N. C.; Eitel, J.; Gamon, J. A.; Hilker, T.; Krofcheck, D. J.; Litvak, M. E.; Naupari, J. A.; Richardson, A. D.; Sonnentag, O.; van Leeuwen, M.

    2011-12-01

    Increasing the spatial and temporal density of automated environmental sensing networks is necessary to quantify shifts in plant structure (e.g., leaf area index) and function (e.g., photosynthesis). Improving detection sensitivity can facilitate a mechanistic understanding by better linking plant processes to environmental change. Spectral radiometer measurements can be highly useful for tracking plant structure and function from diurnal to seasonal time scales and calibrating and validating satellite- and aircraft-based spectral measurements. However, dense ground networks of such instruments are challenging to establish due to the cost and complexity of automated instrument deployment. We therefore developed simple to operate, lightweight and inexpensive narrowband (~10nm bandwidth) spectral instruments capable of continuously measuring four to six discrete bands that have proven capacity to describe key physiological processes and structural features of plant canopies. These bands are centered at 530, 570, 675, 800, 880, and 970 nm to enable calculation of the physiological reflectance index (PRI), normalized difference vegetation index (NDVI), green NDVI (gNDVI), and water band index (WBI) collected above and within vegetation canopies. To date, measurements have been collected above grassland, semi-arid shrub steppe, piñon-juniper woodland, dense conifer forest, mixed deciduous-conifer forest, and cropland canopies, with additional measurements collected along vertical transects through a temperate conifer rainforest. Findings from this work indicate not only that key shifts in plant phenology, physiology, and structure can be captured using such instruments, but that the temporally dense nature of the measurements can help to disentangle heretofore unreported complexities of simultaneous phenological and structural change on canopy reflectance.

  13. 75 FR 27504 - Substantial Product Hazard List: Hand-Held Hair Dryers

    Science.gov (United States)

    2010-05-17

    ... immersion during their use. Section 15(a) of the CPSA defines ``substantial product hazard'' to include, a....'' Hand-held hair dryers routinely contain open-coil heating elements that are, in essence, uninsulated..., bathtub, or lavatory). The proposed rule would define ``hand-held hair dryer'' as ``an electrical...

  14. Descent imager/spectral radiometer (DISR) instrument aboard the Huygens probe of Titan

    Science.gov (United States)

    Tomasko, Martin G.; Doose, Lyn R.; Smith, Peter H.; Fellows, C.; Rizk, B.; See, C.; Bushroe, M.; McFarlane, E.; Wegryn, E.; Frans, E.; Clark, R.; Prout, M.; Clapp, S.

    1996-10-01

    The Huygen's probe of the atmosphere of Saturn's moon Titan includes one optical instrument sensitive to the wavelengths of solar radiation. The goals of this investigation fall into four broad areas: 1) the measurement of the profile of solar heating to support an improved understanding of the thermal balance of Titan and the role of the greenhouse effect in maintaining Titan's temperature structure; 2) the measurement of the size, vertical distribution, and optical properties of the aerosol and cloud particles in Titan's atmosphere to support studies of the origin, chemistry, life cycles, and role in the radiation balance of Titan played by these particles; 3) the composition of the atmosphere, particularly the vertical profile of the mixing ratio of methane, a condensable constituent in Titan's atmosphere; and 4) the physical state, composition, topography, and physical processes at work in determining the nature of the surface of Titan and its interaction with Titan's atmosphere. In order to accomplish these objectives, the Descent Imager/Spectral Radiometer (DISR) instrument makes extensive use of fiber optics to bring the light from several different sets of foreoptics to a silicon CCD detector, to a pair of InGaAs linear array detectors, and to three silicon photometers. Together these detectors permit DISR to make panoramic images of the clouds and surface of Titan, to measure the spectrum of upward and downward streaming sunlight from 350 to 1700 nm at a resolving power of about 200, to measure the reflection spectrum of >= 3000 locations on the surface, to measure the brightness and polarization of the solar aureole between 4 and 30 degrees from the sun at 500 and 935 nm, to separate the direct and diffuse downward solar flux at each wavelength measured, and to measure the continuous reflection spectrum of the ground between 850 and 1600 nm using an onboard lamp in the last 100 m of the descent.

  15. Hand-held hyperspectral imager for chemical/biological and environmental applications

    Science.gov (United States)

    Hinnrichs, Michele; Piatek, Bob

    2004-03-01

    A small, hand held, battery operated imaging infrared spectrometer, Sherlock, has been developed by Pacific Advanced Technology and was field tested in early 2003. The Sherlock spectral imaging camera has been designed for remote gas leak detection, however, the architecture of the camera is versatile enough that it can be applied to numerous other applications such as homeland security, chemical/biological agent detection, medical and pharmaceutical applications as well as standard research and development. This paper describes the Sherlock camera, theory of operations, shows current applications and touches on potential future applications for the camera. The Sherlock has an embedded Power PC and performs real-time-image processing function in an embedded FPGA. The camera has a built in LCD display as well as output to a standard monitor, or NTSC display. It has several I/O ports, ethernet, firewire, RS232 and thus can be easily controlled from a remote location. In addition, software upgrades can be performed over the ethernet eliminating the need to send the camera back to the factory for a retrofit. Using the USB port a mouse and key board can be connected and the camera can be used in a laboratory environment as a stand alone imaging spectrometer.

  16. 78 FR 27441 - NIJ Evaluation of Hand-Held Cell Phone Detector Devices

    Science.gov (United States)

    2013-05-10

    ...The National Institute of Justice (NIJ) is soliciting interest in supplying hand-held cell phone detector devices for participation in an evaluation by the NIJ Corrections Technology Center of Excellence (CXCoE).

  17. Long-term temporal stability of the National Institute of Standards and Technology spectral irradiance scale determined with absolute filter radiometers

    International Nuclear Information System (INIS)

    Yoon, Howard W.; Gibson, Charles E.

    2002-01-01

    The temporal stability of the National Institute of Standards and Technology (NIST) spectral irradiance scale as measured with broadband filter radiometers calibrated for absolute spectral irradiance responsivity is described. The working standard free-electron laser (FEL) lamps and the check standard FEL lamps have been monitored with radiometers in the ultraviolet and the visible wavelength regions. The measurements made with these two radiometers reveal that the NIST spectral irradiance scale as compared with an absolute thermodynamic scale has not changed by more than 1.5% in the visible from 1993 to 1999. Similar measurements in the ultraviolet reveal that the corresponding change is less than 1.5% from 1995 to 1999. Furthermore, a check of the spectral irradiance scale by six different filter radiometers calibrated for absolute spectral irradiance responsivity based on the high-accuracy cryogenic radiometer shows that the agreement between the present scale and the detector-based scale is better than 1.3% throughout the visible to the near-infrared wavelength region. These results validate the assigned spectral irradiance of the widely disseminated NIST or NIST-traceable standard sources

  18. Ozone, spectral irradiance and aerosol measurements with the Brewer spectro radiometer

    International Nuclear Information System (INIS)

    Marenco, F.; Di Sarra, A.

    2001-01-01

    In this technical report a detailed description of the Brewer spectro radiometer, a widespread instrument for ozone and ultraviolet radiation, is given. The methodologies used to measure these quantities and for instrument calibration are described in detail. Finally a new methodology, developed by ENEA to derive the aerosol optical depth from the Brewer routine total ozone measurements, is described. This methodology is based on Langley extrapolation, on the determination of the transmissivity of the Brewer neutral density filters, and on a statistically significant number of half days of measurements obtained in could-free conditions. Results of this method, obtained with the Brewer of the ENEA station for climate observations Roberto Sarao, located in the island of Lampedusa, are reported. These results confirm the validity of the method, thanks to independent measurements taken in 1999 with a Multi filter Rotating Shadow band Radiometer. This methodology allows researchers to obtain an aerosol climatology from ozone measurements obtained at several sites world-wide [it

  19. Ultrasonography with a hand-held device for the diagnosis of acute appendicitis

    International Nuclear Information System (INIS)

    Kameda, Toru; Takahashi, Isao

    2009-01-01

    The purpose of this study was to evaluate the accuracy of ultrasonography (US) with a hand-held device for the diagnosis of acute appendicitis in the emergency room. US with a hand-held device was performed by the first author in 33 patients suspected of having appendicitis in the emergency room. From these 33 patients, 24 who subsequently underwent computed tomography (CT) or surgery were included in this study. The accuracy of US with the hand-held device for the diagnosis of acute appendicitis was evaluated based on the findings of CT or surgery. CT and surgery were performed in 22 and 12 patients, respectively. Final diagnoses were acute appendicitis (n=18), terminal ileitis (n=2), pelvic inflammatory disease (n=2), diverticulitis (n=1), and ureterolithiasis (n=1). The US yielded a sensitivity of 78% and a positive predictive value of 100%. The shortest distance between the abdominal wall and the appendix measured on CT was less than 40 mm in 11 patients. In ten (91%) of the 11 patients US with the hand-held device showed the swollen appendix. US with a hand-held device is potentially useful in the positive identification of acute appendicitis, but further investigation is needed to prove its utility in the routine diagnosis of acute appendicitis. (author)

  20. Position statement on use of hand-held portable dental X-ray equipment

    International Nuclear Information System (INIS)

    2014-06-01

    The position statement focuses on justification in the medical field, in particular on the use of hand-held portable dental x-ray equipment. It supplements another HERCA position paper, providing a general overview of the use of all hand-held portable X-ray equipment. Key Messages: - HERCA finds that the use of hand-held portable X-ray devices should be discouraged except in special circumstances. - As a general rule, these devices should only be used in scenarios where an intraoral radiograph is deemed necessary for a patient and the use of a fixed or semi-mobile x-ray unit is impractical, e.g.: - nursing homes, residential care facilities or homes for persons with disabilities; - forensic odontology, - military operations abroad without dental facilities

  1. Driver hand-held cellular phone use: a four-year analysis.

    Science.gov (United States)

    Eby, David W; Vivoda, Jonathon M; St Louis, Renée M

    2006-01-01

    The use of hand-held cellular (mobile) phones while driving has stirred more debate, passion, and research than perhaps any other traffic safety issue in the past several years. There is ample research showing that the use of either hand-held or hands-free cellular phones can lead to unsafe driving patterns. Whether or not these performance deficits increase the risk of crash is difficult to establish, but recent studies are beginning to suggest that cellular phone use elevates crash risk. The purpose of this study was to assess changes in the rate of hand-held cellular phone use by motor-vehicle drivers on a statewide level in Michigan. This study presents the results of 13 statewide surveys of cellular phone use over a 4-year period. Hand-held cellular phone use data were collected through direct observation while vehicles were stopped at intersections and freeway exit ramps. Data were weighted to be representative of all drivers traveling during daylight hours in Michigan. The study found that driver hand-held cellular phone use has more than doubled between 2001 and 2005, from 2.7% to 5.8%. This change represents an average increase of 0.78 percentage points per year. The 5.8% use rate observed in 2005 means that at any given daylight hour, around 36,550 drivers were conversing on cellular phones while driving on Michigan roadways. The trend line fitted to these data predicts that by the year 2010, driver hand-held cellular phone use will be around 8.6%, or 55,000 drivers at any given daylight hour. These results make it clear that cellular phone use while driving will continue to be an important traffic safety issue, and highlight the importance of continued attempts to generate new ways of alleviating this potential hazard.

  2. How to use hand-held computers to evaluate wood drying.

    Science.gov (United States)

    Howard N. Rosen; Darrell S. Martin

    1985-01-01

    Techniques have been developed to evaluate end generate wood drying curves with hand-held computers (3-5K memory). Predictions of time to dry to a specific moisture content, drying rates, and other characteristics of wood drying curves can be made. The paper describes the development of programs and illustrates their use.

  3. 78 FR 73415 - Safety Standard for Hand-Held Infant Carriers

    Science.gov (United States)

    2013-12-06

    ... modifications to the ASTM test procedure set forth in ASTM F2050-12 so that the test produces more repeatable... skills necessary for the preparation of reports or records; and a description of the steps the agency has... the Rule on Small Business There are at least 47 firms currently known to be marketing hand- held...

  4. Survey reveals public open to ban on hand-held cell phone use and texting.

    Science.gov (United States)

    2013-01-01

    A study performed by the Bureau of Transportation Statistics (BTS) reveals that the public is open to a ban on hand-held cell phone use while driving. The study is based on data from 2009s Omnibus Household Survey (OHS), which is administered by B...

  5. Applying Hand-Held 3D Printing Technology to the Teaching of VSEPR Theory

    Science.gov (United States)

    Dean, Natalie L.; Ewan, Corrina; McIndoe, J. Scott

    2016-01-01

    The use of hand-held 3D printing technology provides a unique and engaging approach to learning VSEPR theory by enabling students to draw three-dimensional depictions of different molecular geometries, giving them an appreciation of the shapes of the building blocks of complex molecular structures. Students are provided with 3D printing pens and…

  6. Radiation safety evaluation of a hand-held, battery operated image intensifier

    International Nuclear Information System (INIS)

    Wilson, O.J.; Young, B.F.

    1987-01-01

    A portable, hand-held, fluoroscopic unit intended for medical and industrial use was tested to verify the claim of the manufacturers that the radiation doses to the patient and user are low, and comparable to those received from standard radiographic procedures. The first claim was substantiated but not the second. A number of concerns arising from the use of this unit are discussed

  7. Integrating a Hand Held computer and Stethoscope into a Fetal Monitor

    Science.gov (United States)

    Ahmad Soltani, Mitra

    2009-01-01

    This article presents procedures for modifying a hand held computer or personal digital assistant (PDA) into a versatile device functioning as an electronic stethoscope for fetal monitoring. Along with functioning as an electronic stethoscope, a PDA can provide a useful information source for a medical trainee. Feedback from medical students, residents and interns suggests the device is well accepted by medical trainees. PMID:20165517

  8. The Weak Link HP-41C hand-held calculator program

    Science.gov (United States)

    Ross A. Phillips; Penn A. Peters; Gary D. Falk

    1982-01-01

    The Weak Link hand-held calculator program (HP-41C) quickly analyzes a system for logging production and costs. The production equations model conventional chain saw, skidder, loader, and tandemaxle truck operations in eastern mountain areas. Production of each function of the logging system may be determined so that the system may be balanced for minimum cost. The...

  9. Hand-held transendoscopic robotic manipulators: A transurethral laser prostate surgery case study.

    Science.gov (United States)

    Hendrick, Richard J; Mitchell, Christopher R; Herrell, S Duke; Webster, Robert J

    2015-11-01

    Natural orifice endoscopic surgery can enable incisionless approaches, but a major challenge is the lack of small and dexterous instrumentation. Surgical robots have the potential to meet this need yet often disrupt the clinical workflow. Hand-held robots that combine thin manipulators and endoscopes have the potential to address this by integrating seamlessly into the clinical workflow and enhancing dexterity. As a case study illustrating the potential of this approach, we describe a hand-held robotic system that passes two concentric tube manipulators through a 5 mm port in a rigid endoscope for transurethral laser prostate surgery. This system is intended to catalyze the use of a clinically superior, yet rarely attempted, procedure for benign prostatic hyperplasia. This paper describes system design and experiments to evaluate the surgeon's functional workspace and accuracy using the robot. Phantom and cadaver experiments demonstrate successful completion of the target procedure via prostate lobe resection.

  10. A study of cladding technology on tube wall surface by a hand-held laser torch

    International Nuclear Information System (INIS)

    Terada, Takaya; Nishimura, Akihiko; Oka, Kiyoshi; Moriyama, Taku; Matsuda, Hiroyasu

    2015-01-01

    New maintenance technique was proposed using a hand-held laser torch for aging chemical plants and power plants. The hand-held laser torch was specially designed to be able to access limited tubular space in various cases. A composite-type optical fiberscope was composed of a center fiber for beam delivery and surrounded fibers for visible image delivery. Laser irradiation on a work pieces with the best accuracy of filler wire was carried out. And, we found that the optimized wire-feed speed was 2 mm/s in laser cladding. We succeeded to make a line clad on the inner wall of 23 mm tube. This technique was discussed to be applied to the maintenance for cracks or corrosions of tubes in various harsh environments. (author)

  11. Hand held lasers, a hazard to aircraft: How do we address this?

    Science.gov (United States)

    Barat, K.

    2015-10-01

    The availability of hand held lasers, commonly termed "laser pointers" is easy and wide spread, through commercial web sites and brick & mortar stores. The output of these hand held devices ranges from 1-5 milliWatts (mW) the legal laser pointer output limit, to 5000mW (5Watts). This is thousand times the maximum limit for pointers. Sadly the abuse of these devices is also wide spread. Over the last few years over 3000 aircraft are exposed to laser hits per year. While these aircraft exposures are of no danger to the aircraft frame but they can cause pilot distractions with the potential to cause a serve accident. The presentation will discuss the problem review visual effects, the regulatory response and how educators need to be aware of the problem and can take steps to educate students in the hope of having an effect.

  12. Leakage and scattered radiation from hand-held dental x-ray unit

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Kyung [Dankook Univ. School of Dentistry, Seoul (Korea, Republic of)

    2007-06-15

    To compare the leakage and scattered radiation from hand-held dental X-ray unit with radiation from fixed dental X-ray unit. For evaluation we used one hand-held dental X-ray unit and Oramatic 558 (Trophy Radiologie, France), a fixed dental X-ray unit. Doses were measured with Unfors Multi-O-Meter 512L at the right and left hand levels of X-ray tube head part for the scattered and leakage radiation when human skull DXTTR {iota}{iota}{iota} was exposed to both dental X-ray units. And for the leakage radiation only, doses were measured at the immediately right, left, superior and posterior side of the tube head part when air was exposed. Exposure parameters of hand-held dental X-ray unit were 70 kVp, 3 mA , 0.1 second, and of fixed X-ray unit 70 kVp, 8 mA, 0.45 second. The mean dose at the hand level when human skull DXTTR {iota}{iota}{iota} was exposed with portable X-ray unit 6.39 {mu}Gy, and the mean dose with fixed X-ray unit 3.03 {mu}Gy (p<0.001). The mean dose at the immediate side of the tube head part when air was exposed with portable X-ray unit was 2.97 {mu}Gy and with fixed X-ray unit the mean dose was 0.68 {mu}Gy (p<0.01). The leakage and scattered radiation from hand-held dental radiography was greater than from fixed dental radiography.

  13. Precise intraoperative location of gastrointestinal bleeding with a hand-held counter. Work in progress

    International Nuclear Information System (INIS)

    Williamson, M.R.; Boyd, C.M.; McGuire, E.L.

    1986-01-01

    The nuclear medicine bleeding scan is frequently insufficient to locate sites of bleeding precisely, in spite of its great sensitivity. A small, hand-held Geiger-Mueller counter, placed directly on exposed intestine in the operating room, enables precise location of the probable bleeding site. In three patients, the technique allowed a minimal amount of intestine to be resected, distinguished between large- and small-intestinal hemorrhage, and eliminated other foci as sites of bleeding.A

  14. Leakage and scattered radiation from hand-held dental x-ray unit

    International Nuclear Information System (INIS)

    Kim, Eun Kyung

    2007-01-01

    To compare the leakage and scattered radiation from hand-held dental X-ray unit with radiation from fixed dental X-ray unit. For evaluation we used one hand-held dental X-ray unit and Oramatic 558 (Trophy Radiologie, France), a fixed dental X-ray unit. Doses were measured with Unfors Multi-O-Meter 512L at the right and left hand levels of X-ray tube head part for the scattered and leakage radiation when human skull DXTTR ΙΙΙ was exposed to both dental X-ray units. And for the leakage radiation only, doses were measured at the immediately right, left, superior and posterior side of the tube head part when air was exposed. Exposure parameters of hand-held dental X-ray unit were 70 kVp, 3 mA , 0.1 second, and of fixed X-ray unit 70 kVp, 8 mA, 0.45 second. The mean dose at the hand level when human skull DXTTR ΙΙΙ was exposed with portable X-ray unit 6.39 μGy, and the mean dose with fixed X-ray unit 3.03 μGy (p<0.001). The mean dose at the immediate side of the tube head part when air was exposed with portable X-ray unit was 2.97 μGy and with fixed X-ray unit the mean dose was 0.68 μGy (p<0.01). The leakage and scattered radiation from hand-held dental radiography was greater than from fixed dental radiography

  15. Validity of maximal isometric knee extension strength measurements obtained via belt-stabilized hand-held dynamometry in healthy adults.

    Science.gov (United States)

    Ushiyama, Naoko; Kurobe, Yasushi; Momose, Kimito

    2017-11-01

    [Purpose] To determine the validity of knee extension muscle strength measurements using belt-stabilized hand-held dynamometry with and without body stabilization compared with the gold standard isokinetic dynamometry in healthy adults. [Subjects and Methods] Twenty-nine healthy adults (mean age, 21.3 years) were included. Study parameters involved right side measurements of maximal isometric knee extension strength obtained using belt-stabilized hand-held dynamometry with and without body stabilization and the gold standard. Measurements were performed in all subjects. [Results] A moderate correlation and fixed bias were found between measurements obtained using belt-stabilized hand-held dynamometry with body stabilization and the gold standard. No significant correlation and proportional bias were found between measurements obtained using belt-stabilized hand-held dynamometry without body stabilization and the gold standard. The strength identified using belt-stabilized hand-held dynamometry with body stabilization may not be commensurate with the maximum strength individuals can generate; however, it reflects such strength. In contrast, the strength identified using belt-stabilized hand-held dynamometry without body stabilization does not reflect the maximum strength. Therefore, a chair should be used to stabilize the body when performing measurements of maximal isometric knee extension strength using belt-stabilized hand-held dynamometry in healthy adults. [Conclusion] Belt-stabilized hand-held dynamometry with body stabilization is more convenient than the gold standard in clinical settings.

  16. The reliability and validity of hand-held refractometry water content measures of hydrogel lenses.

    Science.gov (United States)

    Nichols, Jason J; Mitchell, G Lynn; Good, Gregory W

    2003-06-01

    To investigate within- and between-examiner reliability and validity of hand-held refractometry water content measures of hydrogel lenses. Nineteen lenses of various nominal water contents were examined by two examiners on two occasions separated by 1 hour. An Atago N2 hand-held refractometer was used for all water content measures. Lenses were presented in a random order to each examiner by a third party, and examiners were masked to any potential lens identifiers. Intraclass correlation coefficients (ICC), 95% limits of agreement, and Wilcoxon signed rank test were used to characterize the within- and between-examiner reliability and validity of lens water content measures. Within-examiner reliability was excellent (ICC, 0.97; 95% limits of agreement, -3.6% to +5.7%), and the inter-visit mean difference of 1.1 +/- 2.4% was not biased (p = 0.08). Between-examiner reliability was also excellent (ICC, 0.98; 95% limits of agreement, -4.1% to +3.9%). The mean difference between examiners was -0.1 +/- 2.1% (p = 0.83). The mean difference between the nominally reported water content and our water content measures was -2.1 +/- 1.7% (p refractometry and is material dependent. Therefore, investigators may need to account for bias when measuring hydrogel lens water content via hand-held refractometry.

  17. Gen-2 Hand-Held Optical Imager towards Cancer Imaging: Reflectance and Transillumination Phantom Studies

    Directory of Open Access Journals (Sweden)

    Anuradha Godavarty

    2012-02-01

    Full Text Available Hand-held near-infrared (NIR optical imagers are developed by various researchers towards non-invasive clinical breast imaging. Unlike these existing imagers that can perform only reflectance imaging, a generation-2 (Gen-2 hand-held optical imager has been recently developed to perform both reflectance and transillumination imaging. The unique forked design of the hand-held probe head(s allows for reflectance imaging (as in ultrasound and transillumination or compressed imaging (as in X-ray mammography. Phantom studies were performed to demonstrate two-dimensional (2D target detection via reflectance and transillumination imaging at various target depths (1–5 cm deep and using simultaneous multiple point illumination approach. It was observed that 0.45 cc targets were detected up to 5 cm deep during transillumination, but limited to 2.5 cm deep during reflectance imaging. Additionally, implementing appropriate data post-processing techniques along with a polynomial fitting approach, to plot 2D surface contours of the detected signal, yields distinct target detectability and localization. The ability of the gen-2 imager to perform both reflectance and transillumination imaging allows its direct comparison to ultrasound and X-ray mammography results, respectively, in future clinical breast imaging studies.

  18. Potential role of a new hand-held miniature gamma camera in performing minimally invasive parathyroidectomy

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, Joaquin; Lledo, Salvador [University of Valencia, Clinic University Hospital, Department of Surgery, Valencia (Spain); Ferrer-Rebolleda, Jose [Clinic University Hospital, Department of Nuclear Medicine, Valencia (Spain); Cassinello, Norberto [Clinic University Hospital, Unit of Endocrinologic and Bariatric Surgery, Valencia (Spain)

    2007-02-15

    Sestamibi scans have increased the use of minimally invasive parathyroidectomy (MIP) to treat primary hyperparathyroidism (PHPT) when caused by a parathyroid single adenoma. The greatest concern for surgeons remains the proper identification of pathological glands in a limited surgical field. We have studied the usefulness of a new hand-held miniature gamma camera (MGC) when used intraoperatively to locate parathyroid adenomas. To our knowledge this is the first report published on this subject in the scientific literature. Five patients with PHPT secondary to a single adenoma, positively diagnosed by preoperative sestamibi scans, underwent a MIP. A gamma probe for radioguided surgery and the new hand-held MGC were used consecutively to locate the pathological glands. This new MGC has a module composed of a high-resolution interchangeable collimator and a CsI(Na) scintillating crystal. It has dimensions of around 15 cm x 8 cm x 9 cm and weighs 1 kg. The intraoperative assay of PTH (ioPTH) was used to confirm the complete resection of pathological tissue. All cases were operated on successfully by a MIP. The ioPTH confirmed the excision of all pathological tissues. The MGC proved its usefulness in all patients, even in a difficult case in which the first attempt with the gamma probe failed. In all cases it offered real-time accurate intraoperative images. The hand-held MGC is a useful instrument in MIP for PHPT. It may be used to complement the standard tools used to date, or may even replace them, at least in selected cases of single adenomas. (orig.)

  19. Potential role of a new hand-held miniature gamma camera in performing minimally invasive parathyroidectomy

    International Nuclear Information System (INIS)

    Ortega, Joaquin; Lledo, Salvador; Ferrer-Rebolleda, Jose; Cassinello, Norberto

    2007-01-01

    Sestamibi scans have increased the use of minimally invasive parathyroidectomy (MIP) to treat primary hyperparathyroidism (PHPT) when caused by a parathyroid single adenoma. The greatest concern for surgeons remains the proper identification of pathological glands in a limited surgical field. We have studied the usefulness of a new hand-held miniature gamma camera (MGC) when used intraoperatively to locate parathyroid adenomas. To our knowledge this is the first report published on this subject in the scientific literature. Five patients with PHPT secondary to a single adenoma, positively diagnosed by preoperative sestamibi scans, underwent a MIP. A gamma probe for radioguided surgery and the new hand-held MGC were used consecutively to locate the pathological glands. This new MGC has a module composed of a high-resolution interchangeable collimator and a CsI(Na) scintillating crystal. It has dimensions of around 15 cm x 8 cm x 9 cm and weighs 1 kg. The intraoperative assay of PTH (ioPTH) was used to confirm the complete resection of pathological tissue. All cases were operated on successfully by a MIP. The ioPTH confirmed the excision of all pathological tissues. The MGC proved its usefulness in all patients, even in a difficult case in which the first attempt with the gamma probe failed. In all cases it offered real-time accurate intraoperative images. The hand-held MGC is a useful instrument in MIP for PHPT. It may be used to complement the standard tools used to date, or may even replace them, at least in selected cases of single adenomas. (orig.)

  20. Comparative Geometrical Accuracy Investigations of Hand-Held 3d Scanning Systems - AN Update

    Science.gov (United States)

    Kersten, T. P.; Lindstaedt, M.; Starosta, D.

    2018-05-01

    Hand-held 3D scanning systems are increasingly available on the market from several system manufacturers. These systems are deployed for 3D recording of objects with different size in diverse applications, such as industrial reverse engineering, and documentation of museum exhibits etc. Typical measurement distances range from 0.5 m to 4.5 m. Although they are often easy-to-use, the geometric performance of these systems, especially the precision and accuracy, are not well known to many users. First geometrical investigations of a variety of diverse hand-held 3D scanning systems were already carried out by the Photogrammetry & Laser Scanning Lab of the HafenCity University Hamburg (HCU Hamburg) in cooperation with two other universities in 2016. To obtain more information about the accuracy behaviour of the latest generation of hand-held 3D scanning systems, HCU Hamburg conducted further comparative geometrical investigations using structured light systems with speckle pattern (Artec Spider, Mantis Vision PocketScan 3D, Mantis Vision F5-SR, Mantis Vision F5-B, and Mantis Vision F6), and photogrammetric systems (Creaform HandySCAN 700 and Shining FreeScan X7). In the framework of these comparative investigations geometrically stable reference bodies were used. The appropriate reference data was acquired by measurements with two structured light projection systems (AICON smartSCAN and GOM ATOS I 2M). The comprehensive test results of the different test scenarios are presented and critically discussed in this contribution.

  1. A hand-held sensor for analyses of local distributions of magnetic fields and losses

    CERN Document Server

    Krismanic, G; Baumgartinger, N

    2000-01-01

    The paper describes a novel sensor for non-destructive analyses of local field and loss distributions in laminated soft magnetic cores, such as transformer cores. It was designed for rapid information on comparative local degrees of inhomogeneity, e.g., for the estimation of local building factors. Similar to a magnifying glass with handle, the compact hand-held sensor contains extremely sharp needle electrodes for the detection of the induction vector B as well as double-field coils for the vector H. Losses P are derived from the Poynting law. Applied to inner -- or also outer -- core regions, the sensor yields instantaneous computer displays of local H, B, and P.

  2. Balancing fast-rotating parts of hand-held machine drive

    Science.gov (United States)

    Korotkov, V. S.; Sicora, E. A.; Nadeina, L. V.; Yongzheng, Wang

    2018-03-01

    The article considers the issues related to the balancing of fast rotating parts of the hand-held machine drive including a wave transmission with intermediate rolling elements, which is constructed on the basis of the single-phase collector motor with a useful power of 1 kW and a nominal rotation frequency of 15000 rpm. The forms of balancers and their location are chosen. The method of balancing is described. The scheme for determining of residual unbalance in two correction planes is presented. Measurement results are given in tables.

  3. Neurosurgical hand-held optical coherence tomography (OCT) forward-viewing probe

    Science.gov (United States)

    Sun, Cuiru; Lee, Kenneth K. C.; Vuong, Barry; Cusimano, Michael; Brukson, Alexander; Mariampillai, Adrian; Standish, Beau A.; Yang, Victor X. D.

    2012-02-01

    A prototype neurosurgical hand-held optical coherence tomography (OCT) imaging probe has been developed to provide micron resolution cross-sectional images of subsurface tissue during open surgery. This new ergonomic hand-held probe has been designed based on our group's previous work on electrostatically driven optical fibers. It has been packaged into a catheter probe in the familiar form factor of the clinically accepted Bayonet shaped neurosurgical non-imaging Doppler ultrasound probes. The optical design was optimized using ZEMAX simulation. Optical properties of the probe were tested to yield an ~20 um spot size, 5 mm working distance and a 3.5 mm field of view. The scan frequency can be increased or decreased by changing the applied voltage. Typically a scan frequency of less than 60Hz is chosen to keep the applied voltage to less than 2000V. The axial resolution of the probe was ~15 um (in air) as determined by the OCT system. A custom-triggering methodology has been developed to provide continuous stable imaging, which is crucial for clinical utility. Feasibility of this probe, in combination with a 1310 nm swept source OCT system was tested and images are presented to highlight the usefulness of such a forward viewing handheld OCT imaging probe. Knowledge gained from this research will lay the foundation for developing new OCT technologies for endovascular management of cerebral aneurysms and transsphenoidal neuroendoscopic treatment of pituitary tumors.

  4. Standard guide to In-Plant performance evaluation of Hand-Held SNM monitors

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1999-01-01

    1.1 This guide is one of a series on the application and evaluation of special nuclear material (SNM) monitors. Other guides in the series are listed in Section 2, and the relationship of in-plant performance evaluation to other procedures described in the series is illustrated in Fig. 1. Hand-held SNM monitors are described in of Guide C1112, and performance criteria illustrating their capabilities can be found in Appendix X1. 1.2 The purpose of this guide to in-plant performance evaluation is to provide a comparatively rapid procedure to verify that a hand-held SNM monitor performs as expected for detecting SNM or alternative test sources or to disclose the need for repair. The procedure can be used as a routine operational evaluation or it can be used to verify performance after a monitor is calibrated. 1.3 In-plant performance evaluations are more comprehensive than daily functional tests. They take place less often, at intervals ranging from weekly to once every three months, and derive their result fr...

  5. Hand-Held Sunphotometers for High School Student Construction and Measuring Aerosol Optical Thickness

    Science.gov (United States)

    Almonor, Linda; Baldwin, C.; Craig, R.; Johnson, L. P.

    2000-01-01

    Science education is taking the teaching of science from a traditional (lecture) approach to a multidimensional sense-making approach which allows teachers to support students by providing exploratory experiences. Using projects is one way of providing students with opportunities to observe and participate in sense-making activity. We created a learning environment that fostered inquiry-based learning. Students were engaged in a variety of Inquiry activities that enabled them to work in cooperative planning teams where respect for each other was encouraged and their ability to grasp, transform and transfer information was enhanced. Summer, 1998: An air pollution workshop was conducted for high school students in the Medgar Evers College/Middle College High School Liberty Partnership Summer Program. Students learned the basics of meteorology: structure and composition of the atmosphere and the processes that cause weather. The highlight of this workshop was the building of hand-held sunphotometers, which measure the intensity of the sunlight striking the Earth. Summer, 1999: high school students conducted a research project which measured the mass and size of ambient particulates and enhanced our ability to observe through land based measurements changes in the optical depth of ambient aerosols over Brooklyn. Students used hand held Sunphotometers to collect data over a two week period and entered it into the NASA GISS database by way of the internet.

  6. Analysis of Information Remaining on Hand Held Devices Offered for Sale on the Second Hand Market

    Directory of Open Access Journals (Sweden)

    Andy Jones

    2008-06-01

    Full Text Available The ownership and use of mobile phones, Personal Digital Assistants and other hand held devices is now ubiquitous both for home and business use. The majority of these devices have a high initial cost, a relatively short period before they become obsolescent and a relatively low second hand value.  As a result of this, when the devices are replaced, there are indications that they tend to be discarded.  As technology has continued to develop, it has led to an increasing diversity in the number and type of devices that are available, and the processing power and the storage capacity of the digital storage in the device. All organisations, whether in the public or private sector increasingly use hand held devices that contain digital media for the storage of information relating to their business, their employees or their customers. Similarly, individual private users increasingly use hand held devices containing digital media for the storage of information relating to their private lives.The research revealed that a significant number of organisations and private users are ignorant or misinformed about the volume and type of information that is stored on the hand held devices and the media on which it is stored.  It is apparent that they have either not considered, or are unaware of, the potential impact of this information becoming available to their competitors or those with criminal intent.This main purpose of this study was to gain an understanding of the volume and type of information that may remain on hand held devices that are offered for sale on the second hand market.  A second aim of the research was to determine the level of damage that could, potentially be caused, if the information that remains on the devices fell into the wrong hands.  The study examined a number of hand held devices that had been obtained from sources in the UK and Australia that ranged from internet auction sites, to private sales and commercial

  7. Gamma-ray detectors for intelligent, hand-held radiation monitors

    International Nuclear Information System (INIS)

    Fehlau, P.E.

    1983-01-01

    Small radiation detectors based on HgI 2 , bismuth germanate (BGO), plastic, or NaI(Tl) detector materials were evaluated for use in small, lighweight radiation monitors. The two denser materials, HgI 2 and BGO, had poor resolution at low-energy and thus performed less well than NaI(Tl) in detecting low-energy gamma rays from bare, enriched uranium. The plastic scintillator, a Compton recoil detector, also performed less well at low gamma-ray energy. Two small NaI(Tl) detectors were suitable for detecting bare uranium and sheilded plutonium. One became part of a new lightweight hand-held monitor and the other found uses as a pole-mounted detector for monitoring hard-to-reach locations

  8. Hand-held dynamic visual noise reduces naturally occurring food cravings and craving-related consumption.

    Science.gov (United States)

    Kemps, Eva; Tiggemann, Marika

    2013-09-01

    This study demonstrated the applicability of the well-established laboratory task, dynamic visual noise, as a technique for reducing naturally occurring food cravings and subsequent food intake. Dynamic visual noise was delivered on a hand-held computer device. Its effects were assessed within the context of a diary study. Over a 4-week period, 48 undergraduate women recorded their food cravings and consumption. Following a 2-week baseline, half the participants watched the dynamic visual noise display whenever they experienced a food craving. Compared to a control group, these participants reported less intense cravings. They were also less likely to eat following a craving and consequently consumed fewer total calories following craving. These findings hold promise for curbing unwanted food cravings and craving-driven consumption in real-world settings. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Design of hand held RID's monitoring system based on embedded system

    International Nuclear Information System (INIS)

    Wang Hongwei; Wei Yixiang

    2008-01-01

    In this paper we introduce the design of monitoring system for the hand held radionuclide identification device (RID), constructed under the embedded operating system of WinCE. At first, we introduce the design of hardware and software platform, and following is the major part of technical view of the software system, including the driver development, P/Invoke mechanism to call the C/C++ subroutines, multi-thread technology. In the experimental hardware platform, we have developed a front-end monitoring system for portable device targeted nuclide identification and orientation. It's a full-featured and flexible system, with the functions of data acquisition, radioactivity locating, data import and export, etc. (authors)

  10. A hand-held 3D laser scanning with global positioning system of subvoxel precision

    International Nuclear Information System (INIS)

    Arias, Nestor; Meneses, Nestor; Meneses, Jaime; Gharbi, Tijani

    2011-01-01

    In this paper we propose a hand-held 3D laser scanner composed of an optical head device to extract 3D local surface information and a stereo vision system with subvoxel precision to measure the position and orientation of the 3D optical head. The optical head is manually scanned over the surface object by the operator. The orientation and position of the 3D optical head is determined by a phase-sensitive method using a 2D regular intensity pattern. This phase reference pattern is rigidly fixed to the optical head and allows their 3D location with subvoxel precision in the observation field of the stereo vision system. The 3D resolution achieved by the stereo vision system is about 33 microns at 1.8 m with an observation field of 60cm x 60cm.

  11. The Complimentary Role of Methoxy-Isobutyl-Isonitrile and Hand-Held Gamma Probe in Adamantinoma

    Science.gov (United States)

    Maharaj, Masha; Korowlay, Nisaar; Ellmann, Prof

    2016-01-01

    Adamantinoma is a rare locally aggressive osteolytic tumor that is found 90% of the time in the diaphysis of the tibia with the remaining lesions found in the fibula and long tubular bones. A case of adamantinoma of the tibia is presented. The added value of nuclear medicine investigations in the workup of this patient is described. A three-phase whole body 99mTc-methylene diphosphonate bone and a whole body 99mTc-methoxy-isobutyl-isonitrile scans were complimentary in the demarcation of viable bone tumor and the assessment of the remainder of the bone and soft tissue to exclude other sites. Intra-operative assistance with a hand-held gamma probe, guided the biopsy of the most metabolically active tumor tissue. Histology revealed a biphasic tumor composed of epithelial and fibrous components, in keeping with an adamantinoma. PMID:26912979

  12. Clinical assessment of hip strength using a hand-held dynamometer is reliable

    DEFF Research Database (Denmark)

    Thorborg, K; Petersen, J; Magnusson, S P

    2010-01-01

    rotation (ER), internal rotation (IR), flexion (FLEX) and extension (EXT) using a hand-held dynamometer. Nine subjects (five males, four females), physically active for at least 2.5 h a week, were included. Twelve standardized isometric strength tests were performed twice with a 1-week interval in between......Hip strength assessment plays an important role in the clinical examination of the hip and groin region. The primary aim of this study was to examine the absolute test-retest measurement variation concerning standardized strength assessments of hip abduction (ABD), adduction (ADD), external...... by the same examiner. The test order was randomized to avoid systematic bias. Measurement variation between sessions was 3-12%. When the maximum value of four measurements was used, test-retest measurement variation was below 10% in 11 of the 12 individual hip strength tests and below 5% in five of the 12...

  13. Implementation of synthetic aperture imaging on a hand-held device

    DEFF Research Database (Denmark)

    Hemmsen, Martin Christian; Kjeldsen, Thomas; Larsen, Lee

    2014-01-01

    -held devices all with different chipsets and a BK Medical UltraView 800 ultrasound scanner emulating a wireless probe. The wireless transmission is benchmarked using an imaging setup consisting of 269 scan lines x 1472 complex samples (1.58 MB pr. frame, 16 frames per second). The measured data throughput...... reached an average of 28.8 MB/s using a LG G2 mobile device, which is more than the required data throughput of 25.3 MB/s. Benchmarking the processing performance for B-mode imaging showed a total processing time of 18.9 ms (53 frames/s), which is less than the acquisition time (62.5 ms).......This paper presents several implementations of Syn- thetic Aperture Sequential Beamforming (SASB) on commer- cially available hand-held devices. The implementations include real-time wireless reception of ultrasound radio frequency sig- nals and GPU processing for B-mode imaging. The proposed...

  14. Digital knowledge in the coat pocket - hand-held personal digital assistants in radiology

    International Nuclear Information System (INIS)

    Niehues, S.M.; Froehlich, M.; Felix, R.; Lemke, A.J.

    2004-01-01

    The personal digital assistant (PDA) enables the independent access to large data in a pocket-sized format. The applications for hand-held computers are growing steadily and can support almost any kind of problem. An overview of the available hardware and software is provided and evaluated. Furthermore, the use of the PDA in the clinical daily routine is described. In view of the numerous software programs available in radiology, the range of software solutions for radiologists is presented. Despite the high acquisition cost, the PDA has already become the digital assistant for the radiologist. After a short time of getting used to the PDA, nobody wants to miss it at work or at home. New technical features and available software programs will continuously increase the integration of the PDA into the medical workflow in the near future. (orig.)

  15. An integrated portable hand-held analyser for real-time isothermal nucleic acid amplification

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Matthew C. [College of Marine Science, University of South Florida, St Petersburg, FL (United States)], E-mail: msmith@marine.usf.edu; Steimle, George; Ivanov, Stan; Holly, Mark; Fries, David P. [College of Marine Science, University of South Florida, St Petersburg, FL (United States)

    2007-08-29

    A compact hand-held heated fluorometric instrument for performing real-time isothermal nucleic acid amplification and detection is described. The optoelectronic instrument combines a Printed Circuit Board/Micro Electro Mechanical Systems (PCB/MEMS) reaction detection/chamber containing an integrated resistive heater with attached miniature LED light source and photo-detector and a disposable glass waveguide capillary to enable a mini-fluorometer. The fluorometer is fabricated and assembled in planar geometry, rolled into a tubular format and packaged with custom control electronics to form the hand-held reactor. Positive or negative results for each reaction are displayed to the user using an LED interface. Reaction data is stored in FLASH memory for retrieval via an in-built USB connection. Operating on one disposable 3 V lithium battery >12, 60 min reactions can be performed. Maximum dimensions of the system are 150 mm (h) x 48 mm (d) x 40 mm (w), the total instrument weight (with battery) is 140 g. The system produces comparable results to laboratory instrumentation when performing a real-time nucleic acid sequence-based amplification (NASBA) reaction, and also displayed comparable precision, accuracy and resolution to laboratory-based real-time nucleic acid amplification instrumentation. A good linear response (R{sup 2} = 0.948) to fluorescein gradients ranging from 0.5 to 10 {mu}M was also obtained from the instrument indicating that it may be utilized for other fluorometric assays. This instrument enables an inexpensive, compact approach to in-field genetic screening, providing results comparable to laboratory equipment with rapid user feedback as to the status of the reaction.

  16. Reliability of measuring hip abductor strength following total knee arthroplasty using a hand-held dynamometer.

    Science.gov (United States)

    Schache, Margaret B; McClelland, Jodie A; Webster, Kate E

    2016-01-01

    To investigate the test-retest reliability of measuring hip abductor strength in patients with total knee arthroplasty (TKA) using a hand-held dynamometer (HHD) with two different types of resistance: belt and manual resistance. Test-retest reliability of 30 subjects (17 female, 13 male, 71.9 ± 7.4 years old), 9.2 ± 2.7 days post TKA was measured using belt and therapist resistance. Retest reliability was calculated with intra-class coefficients (ICC3,1) and 95% confidence intervals (CI) for both the group average and the individual scores. A paired t-test assessed whether a difference existed between the belt and therapist methods of resistance. ICCs were 0.82 and 0.80 for the belt and therapist resisted methods, respectively. Hip abductor strength increases of 8 N (14%) for belt resisted and 14 N (17%) for therapist resisted measurements of the group average exceeded the 95% CI and may represent real change. For individuals, hip abductor strength increases of 33 N (72%) (belt resisted) and 57 N (79%) (therapist resisted) could be interpreted as real change. Hip abductor strength can be reliably measured using HHD in the clinical setting with the described protocol. Belt resistance demonstrated slightly higher test-retest reliability. Reliable measurement of hip abductor muscle strength in patients with TKA is important to ensure deficiencies are addressed in rehabilitation programs and function is maximized. Hip abductor strength can be reliably measured with a hand-held dynamometer in the clinical setting using manual or belt resistance.

  17. An integrated portable hand-held analyser for real-time isothermal nucleic acid amplification

    International Nuclear Information System (INIS)

    Smith, Matthew C.; Steimle, George; Ivanov, Stan; Holly, Mark; Fries, David P.

    2007-01-01

    A compact hand-held heated fluorometric instrument for performing real-time isothermal nucleic acid amplification and detection is described. The optoelectronic instrument combines a Printed Circuit Board/Micro Electro Mechanical Systems (PCB/MEMS) reaction detection/chamber containing an integrated resistive heater with attached miniature LED light source and photo-detector and a disposable glass waveguide capillary to enable a mini-fluorometer. The fluorometer is fabricated and assembled in planar geometry, rolled into a tubular format and packaged with custom control electronics to form the hand-held reactor. Positive or negative results for each reaction are displayed to the user using an LED interface. Reaction data is stored in FLASH memory for retrieval via an in-built USB connection. Operating on one disposable 3 V lithium battery >12, 60 min reactions can be performed. Maximum dimensions of the system are 150 mm (h) x 48 mm (d) x 40 mm (w), the total instrument weight (with battery) is 140 g. The system produces comparable results to laboratory instrumentation when performing a real-time nucleic acid sequence-based amplification (NASBA) reaction, and also displayed comparable precision, accuracy and resolution to laboratory-based real-time nucleic acid amplification instrumentation. A good linear response (R 2 = 0.948) to fluorescein gradients ranging from 0.5 to 10 μM was also obtained from the instrument indicating that it may be utilized for other fluorometric assays. This instrument enables an inexpensive, compact approach to in-field genetic screening, providing results comparable to laboratory equipment with rapid user feedback as to the status of the reaction

  18. Combining heterogenous features for 3D hand-held object recognition

    Science.gov (United States)

    Lv, Xiong; Wang, Shuang; Li, Xiangyang; Jiang, Shuqiang

    2014-10-01

    Object recognition has wide applications in the area of human-machine interaction and multimedia retrieval. However, due to the problem of visual polysemous and concept polymorphism, it is still a great challenge to obtain reliable recognition result for the 2D images. Recently, with the emergence and easy availability of RGB-D equipment such as Kinect, this challenge could be relieved because the depth channel could bring more information. A very special and important case of object recognition is hand-held object recognition, as hand is a straight and natural way for both human-human interaction and human-machine interaction. In this paper, we study the problem of 3D object recognition by combining heterogenous features with different modalities and extraction techniques. For hand-craft feature, although it reserves the low-level information such as shape and color, it has shown weakness in representing hiconvolutionalgh-level semantic information compared with the automatic learned feature, especially deep feature. Deep feature has shown its great advantages in large scale dataset recognition but is not always robust to rotation or scale variance compared with hand-craft feature. In this paper, we propose a method to combine hand-craft point cloud features and deep learned features in RGB and depth channle. First, hand-held object segmentation is implemented by using depth cues and human skeleton information. Second, we combine the extracted hetegerogenous 3D features in different stages using linear concatenation and multiple kernel learning (MKL). Then a training model is used to recognize 3D handheld objects. Experimental results validate the effectiveness and gerneralization ability of the proposed method.

  19. 3D indoor modeling using a hand-held embedded system with multiple laser range scanners

    Science.gov (United States)

    Hu, Shaoxing; Wang, Duhu; Xu, Shike

    2016-10-01

    Accurate three-dimensional perception is a key technology for many engineering applications, including mobile mapping, obstacle detection and virtual reality. In this article, we present a hand-held embedded system designed for constructing 3D representation of structured indoor environments. Different from traditional vehicle-borne mobile mapping methods, the system presented here is capable of efficiently acquiring 3D data while an operator carrying the device traverses through the site. It consists of a simultaneous localization and mapping(SLAM) module, a 3D attitude estimate module and a point cloud processing module. The SLAM is based on a scan matching approach using a modern LIDAR system, and the 3D attitude estimate is generated by a navigation filter using inertial sensors. The hardware comprises three 2D time-flight laser range finders and an inertial measurement unit(IMU). All the sensors are rigidly mounted on a body frame. The algorithms are developed on the frame of robot operating system(ROS). The 3D model is constructed using the point cloud library(PCL). Multiple datasets have shown robust performance of the presented system in indoor scenarios.

  20. In-Season Yield Prediction of Cabbage with a Hand-Held Active Canopy Sensor.

    Science.gov (United States)

    Ji, Rongting; Min, Ju; Wang, Yuan; Cheng, Hu; Zhang, Hailin; Shi, Weiming

    2017-10-08

    Efficient and precise yield prediction is critical to optimize cabbage yields and guide fertilizer application. A two-year field experiment was conducted to establish a yield prediction model for cabbage by using the Greenseeker hand-held optical sensor. Two cabbage cultivars (Jianbao and Pingbao) were used and Jianbao cultivar was grown for 2 consecutive seasons but Pingbao was only grown in the second season. Four chemical nitrogen application rates were implemented: 0, 80, 140, and 200 kg·N·ha -1 . Normalized difference vegetation index (NDVI) was collected 20, 50, 70, 80, 90, 100, 110, 120, 130, and 140 days after transplanting (DAT). Pearson correlation analysis and regression analysis were performed to identify the relationship between the NDVI measurements and harvested yields of cabbage. NDVI measurements obtained at 110 DAT were significantly correlated to yield and explained 87-89% and 75-82% of the cabbage yield variation of Jianbao cultivar over the two-year experiment and 77-81% of the yield variability of Pingbao cultivar. Adjusting the yield prediction models with CGDD (cumulative growing degree days) could make remarkable improvement to the accuracy of the prediction model and increase the determination coefficient to 0.82, while the modification with DFP (days from transplanting when GDD > 0) values did not. The integrated exponential yield prediction equation was better than linear or quadratic functions and could accurately make in-season estimation of cabbage yields with different cultivars between years.

  1. Characterization of wood dust emission from hand-held woodworking machines.

    Science.gov (United States)

    Keller, F-X; Chata, F

    2018-01-01

    This article focuses on the prevention of exposure to wood dust when operating electrical hand-held sawing and sanding machines. A laboratory methodology was developed to measure the dust concentration around machines during operating processes. The main objective was to characterize circular saws and sanders, with the aim of classifying the different power tools tested in terms of dust emission (high dust emitter vs. low dust emitter). A test set-up was developed and is described and a measurement methodology was determined for each of the two operations studied. The robustness of the experimental results is discussed and shows good tendencies. The impact of air-flow extraction rate was assessed and the pressure loss of the system for each machine established. For the circular saws, three machines over the nine tested could be classified in the low dust emitter group. Their mean concentration values measured are between 0.64 and 0.98 mg/m 3 for the low dust emitter group and from 2.55 and 4.37 mg/m 3 for the high dust emitter group. From concentration measurements, a machine classification is possible-one for sanding machines and one for sawing machines-and a ratio from 1-7 is obtained when comparing the results. This classification will be helpful when a choice of high performance power tools, in terms of dust emission, must be made by professionals.

  2. Three-dimensional modeling of physiological tremor for hand-held surgical robotic instruments.

    Science.gov (United States)

    Tatinati, Sivanagaraja; Yan Naing Aye; Pual, Anand; Wei Tech Ang; Veluvolu, Kalyana C

    2016-08-01

    Hand-held robotic instruments are developed to compensate physiological tremor in real-time while augmenting the required precision and dexterity into normal microsurgical work-flow. The hardware (sensors and actuators) and software (causal linear filters) employed for tremor identification and filtering introduces time-varying unknown phase-delay that adversely affects the device performance. The current techniques that focus on three-dimensions (3D) tip position control involves modeling and canceling the tremor in 3-axes (x, y, and z axes) separately. Our analysis with the tremor data recorded from surgeons and novice subjects show that there exists significant correlation in tremor motion across the dimensions. Motivated by this, a new multi-dimensional modeling approach based on extreme learning machines (ELM) is proposed in this paper to correct the phase delay and to accurately model tremulous motion in three dimensions simultaneously. A study is conducted with tremor data recorded from the microsurgeons to analyze the suitability of proposed approach.

  3. Hand-Held Photometer for Instant On-Spot Quantification of Nucleic Acids, Proteins, and Cells.

    Science.gov (United States)

    Li, Shi-Hao; Jain, Abhinav; Tscharntke, Timo; Arnold, Tobias; Trau, Dieter W

    2018-02-20

    This paper presents a novel hand-held photometer, termed "Photopette", for on-spot absorbance measurements of biochemical analytes. The Photopette is a multicomponent, highly portable device with an overall weight of 160 g, which fits within 202 mm × 47 mm × 42 mm. Designed in the form factor of a micropipette, Photopette integrates a photodiode detector with light emitting diodes (LEDs) to form a highly customizable photometer which supports a wide variety of applications within the wavelengths between 260 and 1050 nm. A dual-purpose disposable reflective tip was designed to act as a sample holder and a light-reflecting system, which is in stark contrast to the operation of mainstream spectrophotometers and photometers. Small volume analytes may be measured with low sample loss using this proprietary CuveTip. A user-friendly software application running on smart devices was developed to control and read the values from Photopette via a low-energy Bluetooth link. This one-step strategy allows measurements on-spot without sample transfer, minimizing cross-contamination and human error. The results reported in this paper demonstrate Photopette's great potential to quantify DNA, direct protein, and cell density directly within the laminar flow hood. Results are compared with a Nanodrop 2000c spectrophotometer, a mainstream spectrophotometer for small-volume measurements.

  4. Flexible CMOS low-noise amplifiers for beyond-3G wireless hand-held devices

    Science.gov (United States)

    Becerra-Alvarez, Edwin C.; Sandoval-Ibarra, Federico; de la Rosa, José M.

    2009-05-01

    This paper explores the use of reconfigurable Low-Noise Amplifiers (LNAs) for the implementation of CMOS Radio Frequency (RF) front-ends in the next generation of multi-standard wireless transceivers. Main circuit strategies reported so far for multi-standard LNAs are reviewed and a novel flexible LNA intended for Beyond-3G RF hand-held terminals is presented. The proposed LNA circuit consists of a two-stage topology that combines inductive-source degeneration with PMOS-varactor based tuning network and a programmable load to adapt its performance to different standard specifications without penalizing the circuit noise and with a reduced number of inductors as compared to previous reported reconfigurable LNAs. The circuit has been designed in a 90-nm CMOS technology to cope with the requirements of the GSM, WCDMA, Bluetooth and WLAN (IEEE 802.11b-g) standards. Simulation results, including technology and packaging parasitics, demonstrate correct operation of the circuit for all the standards under study, featuring NF13.3dB and IIP3>10.9dBm, over a 1.85GHz-2.4GHz band, with an adaptive power consumption between 17mW and 22mW from a 1-V supply voltage. Preliminary experimental measurements are included, showing a correct reconfiguration operation within the operation band.

  5. Performance of a new hand-held device for exhaled nitric oxide measurement in adults and children

    Directory of Open Access Journals (Sweden)

    Janson C

    2006-04-01

    Full Text Available Abstract Background Exhaled nitric oxide (NO measurement has been shown to be a valuable tool in the management of patients with asthma. Up to now, most measurements have been done with stationary, chemiluminescence-based NO analysers, which are not suitable for the primary health care setting. A hand-held NO analyser which simplifies the measurement would be of value both in specialized and primary health care. In this study, the performance of a new electrochemical hand-held device for exhaled NO measurements (NIOX MINO was compared with a standard stationary chemiluminescence unit (NIOX. Methods A total of 71 subjects (6–60 years; 36 males, both healthy controls and atopic patients with and without asthma were included. The mean of three approved exhalations (50 ml/s in each device, and the first approved measurement in the hand-held device, were compared with regard to NO readings (Bland-Altman plots, measurement feasibility (success rate with 6 attempts and repeatability (intrasubject SD. Results Success rate was high (≥ 84% in both devices for both adults and children. The subjects represented a FENO range of 8–147 parts per billion (ppb. When comparing the mean of three measurements (n = 61, the median of the intrasubject difference in exhaled NO for the two devices was -1.2 ppb; thus generally the hand-held device gave slightly higher readings. The Bland-Altman plot shows that the 95% limits of agreement were -9.8 and 8.0 ppb. The intrasubject median difference between the NIOX and the first approved measurement in the NIOX MINO was -2.0 ppb, and limits of agreement were -13.2 and 10.2 ppb. The median repeatability for NIOX and NIOX MINO were 1.1 and 1.2 ppb, respectively. Conclusion The hand-held device (NIOX MINO and the stationary system (NIOX are in clinically acceptable agreement both when the mean of three measurements and the first approved measurement (NIOX MINO is used. The hand-held device shows good repeatability, and it

  6. Performance of a new hand-held device for exhaled nitric oxide measurement in adults and children.

    Science.gov (United States)

    Alving, K; Janson, C; Nordvall, L

    2006-04-20

    Exhaled nitric oxide (NO) measurement has been shown to be a valuable tool in the management of patients with asthma. Up to now, most measurements have been done with stationary, chemiluminescence-based NO analysers, which are not suitable for the primary health care setting. A hand-held NO analyser which simplifies the measurement would be of value both in specialized and primary health care. In this study, the performance of a new electrochemical hand-held device for exhaled NO measurements (NIOX MINO) was compared with a standard stationary chemiluminescence unit (NIOX). A total of 71 subjects (6-60 years; 36 males), both healthy controls and atopic patients with and without asthma were included. The mean of three approved exhalations (50 ml/s) in each device, and the first approved measurement in the hand-held device, were compared with regard to NO readings (Bland-Altman plots), measurement feasibility (success rate with 6 attempts) and repeatability (intrasubject SD). Success rate was high (> or = 84%) in both devices for both adults and children. The subjects represented a FENO range of 8-147 parts per billion (ppb). When comparing the mean of three measurements (n = 61), the median of the intrasubject difference in exhaled NO for the two devices was -1.2 ppb; thus generally the hand-held device gave slightly higher readings. The Bland-Altman plot shows that the 95% limits of agreement were -9.8 and 8.0 ppb. The intrasubject median difference between the NIOX and the first approved measurement in the NIOX MINO was -2.0 ppb, and limits of agreement were -13.2 and 10.2 ppb. The median repeatability for NIOX and NIOX MINO were 1.1 and 1.2 ppb, respectively. The hand-held device (NIOX MINO) and the stationary system (NIOX) are in clinically acceptable agreement both when the mean of three measurements and the first approved measurement (NIOX MINO) is used. The hand-held device shows good repeatability, and it can be used successfully on adults and most children

  7. An embedded system developed for hand held assay used in water monitoring

    Science.gov (United States)

    Wu, Lin; Wang, Jianwei; Ramakrishna, Bharath; Hsueh, Mingkai; Liu, Jonathan; Wu, Qufei; Wu, Chao-Cheng; Cao, Mang; Chang, Chein-I.; Jensen, Janet L.; Jensen, James O.; Knapp, Harlan; Daniel, Robert; Yin, Ray

    2005-11-01

    The US Army Joint Service Agent Water Monitor (JSAWM) program is currently interested in an approach that can implement a hardware- designed device in ticket-based hand-held assay (currently being developed) used for chemical/biological agent detection. This paper presents a preliminary investigation of the proof of concept. Three components are envisioned to accomplish the task. One is the ticket development which has been undertaken by the ANP, Inc. Another component is the software development which has been carried out by the Remote Sensing Signal and Image Processing Laboratory (RSSIPL) at the University of Maryland, Baltimore County (UMBC). A third component is an embedded system development which can be used to drive the UMBC-developed software to analyze the ANP-developed HHA tickets on a small pocket-size device like a PDA. The main focus of this paper is to investigate the third component that is viable and is yet to be explored. In order to facilitate to prove the concept, a flatbed scanner is used to replace a ticket reader to serve as an input device. The Stargate processor board is used as the embedded System with Embedded Linux installed. It is connected to an input device such as scanner as well as output devices such as LCD display or laptop etc. It executes the C-Coded processing program developed for this embedded system and outputs its findings on a display device. The embedded system to be developed and investigated in this paper is the core of a future hardware device. Several issues arising in such an embedded system will be addressed. Finally, the proof-of-concept pilot embedded system will be demonstrated.

  8. Utility of hand-held echocardiography in outpatient pediatric cardiology management.

    Science.gov (United States)

    Riley, Alan; Sable, Craig; Prasad, Aparna; Spurney, Christopher; Harahsheh, Ashraf; Clauss, Sarah; Colyer, Jessica; Gierdalski, Marcin; Johnson, Ashley; Pearson, Gail D; Rosenthal, Joanna

    2014-12-01

    Adult patient series have shown hand-held echocardiography (echo) units (HHE) to be accurate for rapid diagnosis and triage. This is the first study to evaluate the ability of HHE to inform decision making in outpatient pediatric cardiology. New pediatric cardiology patients in outpatient clinics staffed by six pediatric cardiologists (experience 1-17 years) were prospectively enrolled if an echocardiogram (echo) was ordered during their initial visit. After history and physical examination and before a standard echo, the cardiologists performed a bedside HHE examination (GE Vscan 1.7-3.8 MHz), documented findings, and made a clinical decision. Diagnoses and decisions based on HHE were compared with final management after the standard echo. The study enrolled 101 subjects (ages 9 days to 19 years). The cardiologists considered HHE imaging adequate for decision making for 80 of the 101 subjects. For 77 of the 80 subjects with acceptable HHE imaging (68/68 normal and 9/12 abnormal standard echoes), the HHE-based primary diagnoses and decisions agreed with the final management. The sensitivity of HHE was 75 % (95 % confidence interval [CI] 43-94 %) and the positive predictive value 100 % (95 % CI 66-100 %) for pediatric heart disease. The agreement between standard echocardiography and HHE imaging was substantial (κ = 0.82). Excluding one of the least experienced cardiologists, HHE provided the basis for correct cardiac diagnoses and management for all the subjects with acceptable HHE imaging (58/58 normal and 9/9 abnormal echoes). In outpatient pediatric cardiology, HHE has potential as a tool to complement physical examination. Further investigation is needed to evaluate how value improves with clinical experience.

  9. Ratioing methods for in-flight response calibration of space-based spectro-radiometers, operating in the solar spectral region

    Science.gov (United States)

    Lobb, Dan

    2017-11-01

    One of the most significant problems for space-based spectro-radiometer systems, observing Earth from space in the solar spectral band (UV through short-wave IR), is in achievement of the required absolute radiometric accuracy. Classical methods, for example using one or more sun-illuminated diffusers as reflectance standards, do not generally provide methods for monitoring degradation of the in-flight reference after pre-flight characterisation. Ratioing methods have been proposed that provide monitoring of degradation of solar attenuators in flight, thus in principle allowing much higher confidence in absolute response calibration. Two example methods are described. It is shown that systems can be designed for relatively low size and without significant additions to the complexity of flight hardware.

  10. Efficacy of hand held, inexpensive UV light sources on Acanthamoeba, causative organism in amoebic keratitis

    Directory of Open Access Journals (Sweden)

    Ivan Cometa

    2010-01-01

    Full Text Available Ivan Cometa1, Andrew Rogerson1, Scott Schatz21Department of Biology, California State University Fresno, Fresno, CA, USA; 2Arizona College of Optometry, Midwestern University, Glendale, AZ, USAAbstract: Multipurpose lens cleaning solutions (MPS fail to consistently kill or inactivate Acanthamoeba cysts and UV irradiation, while effective at high doses, can damage contact lenses. The present study considered synergy of action between MPS and hand-held inexpensive (ie, relatively weak UV irradiation units. Regardless of disinfection method recently formed cysts (<10 days were far more susceptible to treatment than mature cysts (>14 days. This has important implications for future protocols on testing methods for killing amoebae. The study also showed that cysts of different strains (two tested, FLA2 and P120 are variable in their response to MPS, presumably reflecting differences in cyst wall structure and thus permeability to the disinfectant. On the other hand, the effect of UV irradiation was not wall structure dependent. A 6-hour treatment with MPS alone killed trophic amoebae but failed to kill any mature cysts. Cysts of strain FLA2 were killed after 24 hours with MPS but cysts of strain P120 survived. UV irradiation with the larger 4 W unit killed all cysts after 7 minutes and was more effective than the smaller battery-powered unit (after 10 minutes about 50% of cysts were killed. When the larger unit was used with the MPS disinfection, all trophozoites were killed using UV for 3 minutes and MPS for 1 hour. The resistant P120 cysts remained a challenge but a 2- to 4-minute UV treatment followed by MPS for 3 or 6 hours reduced mature cyst survival by about 50%. The small unit in combination with MPS was less effective but did reduce the time required to kill trophic amoebae in MPS (6 hours MPS alone versus 3 hours MPS with a 1-minute UV treatment. In short, inexpensive UV units do enhance MPS disinfection and future lens cleaning systems

  11. Hand-held cell phone use while driving legislation and observed driver behavior among population sub-groups in the United States

    Directory of Open Access Journals (Sweden)

    Toni M. Rudisill

    2017-05-01

    Full Text Available Abstract Background Cell phone use behaviors are known to vary across demographic sub-groups and geographic locations. This study examined whether universal hand-held calling while driving bans were associated with lower road-side observed hand-held cell phone conversations across drivers of different ages (16–24, 25–59, ≥60 years, sexes, races (White, African American, or other, ruralities (suburban, rural, or urban, and regions (Northeast, Midwest, South, and West. Methods Data from the 2008–2013 National Occupant Protection Use Survey were merged with states’ cell phone use while driving legislation. The exposure was presence of a universal hand-held cell phone ban at time of observation. Logistic regression was used to assess the odds of drivers having a hand-held cell phone conversation. Sub-groups differences were assessed using models with interaction terms. Results When universal hand-held cell phone bans were effective, hand-held cell phone conversations were lower across all driver demographic sub-groups and regions. Sub-group differences existed among the sexes (p-value, <0.0001 and regions (p-value, 0.0003. Compared to states without universal hand-held cell phone bans, the adjusted odds ratio (aOR of a driver hand-held phone conversation was 0.34 [95% confidence interval (CI: 0.28, 0.41] for females versus 0.47 (CI 0.40, 0.55 for males and 0.31 (CI 0.25, 0.38 for drivers in Western states compared to 0.47 (CI 0.30, 0.72 in the Northeast and 0.50 (CI 0.38, 0.66 in the South. Conclusions The presence of universal hand-held cell phone bans were associated lower hand-held cell phone conversations across all driver sub-groups and regions. Hand-held phone conversations were particularly lower among female drivers and those from Western states when these bans were in effect. Public health interventions concerning hand-held cell phone use while driving could reasonably target all drivers.

  12. GOES-R Advanced Baseline Imager: spectral response functions and radiometric biases with the NPP Visible Infrared Imaging Radiometer Suite evaluated for desert calibration sites.

    Science.gov (United States)

    Pearlman, Aaron; Pogorzala, David; Cao, Changyong

    2013-11-01

    The Advanced Baseline Imager (ABI), which will be launched in late 2015 on the National Oceanic and Atmospheric Administration's Geostationary Operational Environmental Satellite R-series satellite, will be evaluated in terms of its data quality postlaunch through comparisons with other satellite sensors such as the recently launched Visible Infrared Imaging Radiometer Suite (VIIRS) aboard the Suomi National Polar-orbiting Partnership satellite. The ABI has completed much of its prelaunch characterization and its developers have generated and released its channel spectral response functions (response versus wavelength). Using these responses and constraining a radiative transfer model with ground reflectance, aerosol, and water vapor measurements, we simulate observed top of atmosphere (TOA) reflectances for analogous visible and near infrared channels of the VIIRS and ABI sensors at the Sonoran Desert and White Sands National Monument sites and calculate the radiometric biases and their uncertainties. We also calculate sensor TOA reflectances using aircraft hyperspectral data from the Airborne Visible/Infrared Imaging Spectrometer to validate the uncertainties in several of the ABI and VIIRS channels and discuss the potential for validating the others. Once on-orbit, calibration scientists can use these biases to ensure ABI data quality and consistency to support the numerical weather prediction community and other data users. They can also use the results for ABI or VIIRS anomaly detection and resolution.

  13. PHOCUS radiometer

    Directory of Open Access Journals (Sweden)

    O. Nyström

    2012-06-01

    Full Text Available PHOCUS – Particles, Hydrogen and Oxygen Chemistry in the Upper Summer Mesosphere is a Swedish sounding rocket experiment, launched in July 2011, with the main goal of investigating the upper atmosphere in the altitude range 50–110 km. This paper describes the SondRad instrument in the PHOCUS payload, a radiometer comprising two frequency channels (183 GHz and 557 GHz aimed at exploring the water vapour concentration distribution in connection with the appearance of noctilucent (night shining clouds. The design of the radiometer system has been done in a collaboration between Omnisys Instruments AB and the Group for Advanced Receiver Development (GARD at Chalmers University of Technology where Omnisys was responsible for the overall design, implementation, and verification of the radiometers and backend, whereas GARD was responsible for the radiometer optics and calibration systems.

    The SondRad instrument covers the water absorption lines at 183 GHz and 557 GHz. The 183 GHz channel is a side-looking radiometer, while the 557 GHz radiometer is placed along the rocket axis looking in the forward direction. Both channels employ sub-harmonically pumped Schottky mixers and Fast Fourier Transform Spectrometers (FFTS backends with 67 kHz resolution.

    The radiometers include novel calibration systems specifically adjusted for use with each frequency channel. The 183 GHz channel employs a continuous wave CW pilot signal calibrating the entire receiving chain, while the intermediate frequency chain (the IF-chain of the 557 GHz channel is calibrated by injecting a signal from a reference noise source through a directional coupler.

    The instrument collected complete spectra for both the 183 GHz and the 557 GHz with 300 Hz data rate for the 183 GHz channel and 10 Hz data rate for the 557 GHz channel for about 60 s reaching the apogee of the flight trajectory and 100 s after that. With lossless data compression using variable

  14. Potential Air Contamination During CO2 Angiography Using a Hand-Held Syringe: Theoretical Considerations and Gas Chromatography

    International Nuclear Information System (INIS)

    Cho, David R.; Cho, Kyung J.; Hawkins, Irvin F.

    2006-01-01

    Purpose. To assess air contamination in the hand-held syringes currently used for CO 2 delivery and to determine whether there is an association between their position and the rate of air contamination. Methods. Assessment of air contamination in the syringe (20 ml) included theoretical modeling, mathematical calculation, and gas chromatography (GC). The model was used with Fick's first law to calculate the diffusion of CO 2 and the amount of air contamination. For GC studies, the syringes were placed in the upright, horizontal, and inverted positions and gas samples were obtained after 5, 10, 20, 30, and 60 min. All trials with each position for each sampling time were performed five times. Results. The amounts of air contamination with time calculated mathematically were 5-10% less than those of GC. With the diffusivity of air-CO 2 at 0.1599 cm 2 /sec (9.594 cm 2 /min), air contamination was calculated to be 60% at 60 min. With GC air contamination was 13% at 5 min, 31% at 20 min, 43% at 30 min, and 68% at 60 min. There was no difference in air contamination between the different syringe positions. Conclusion. Air contamination occurs in hand-held syringes filled with CO 2 when they are open to the ambient air. The amounts of air contamination over time are similar among syringes placed in the upright, horizontal, and inverted positions

  15. Potential air contamination during CO2 angiography using a hand-held syringe: theoretical considerations and gas chromatography.

    Science.gov (United States)

    Cho, David R; Cho, Kyung J; Hawkins, Irvin F

    2006-01-01

    To assess air contamination in the hand-held syringes currently used for CO2 delivery and to determine whether there is an association between their position and the rate of air contamination. Assessment of air contamination in the syringe (20 ml) included theoretical modeling, mathematical calculation, and gas chromatography (GC). The model was used with Fick's first law to calculate the diffusion of CO2 and the amount of air contamination. For GC studies, the syringes were placed in the upright, horizontal, and inverted positions and gas samples were obtained after 5, 10, 20, 30, and 60 min. All trials with each position for each sampling time were performed five times. The amounts of air contamination with time calculated mathematically were 5-10% less than those of GC. With the diffusivity of air-CO2 at 0.1599 cm2/sec (9.594 cm2/min), air contamination was calculated to be 60% at 60 min. With GC air contamination was 13% at 5 min, 31% at 20 min, 43% at 30 min, and 68% at 60 min. There was no difference in air contamination between the different syringe positions. Air contamination occurs in hand-held syringes filled with CO2 when they are open to the ambient air. The amounts of air contamination over time are similar among syringes placed in the upright, horizontal, and inverted positions.

  16. Development and performance of a hand-held CZT detector for in-situ measurements at the emergency response

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Young Yong; Chung, Kun Ho; Kim, Chang Jong; Lee, Wan No; Choi, Geun Sik; Kang, Mun Ja [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Yoon, Jin [SI Detection Co. Ltd, Daejeon (Korea, Republic of)

    2016-06-15

    A hand-held detector for an emergency response was developed for nuclide identification and to estimate the information of the ambient dose rate in the scene of an accident as well as the radioactivity of the contaminants. To achieve this, the most suitable sensor was first selected as a cadmium zinc telluride (CZT) semiconductor and the signal processing unit from a sensor and the signal discrimination and storage unit were successfully manufactured on a printed circuit board. The performance of the developed signal processing unit was then evaluated to have an energy resolution of about 14 keV at 662 keV. The system control unit was also designed to operate the CZT detector, monitor the detector, battery, and interface status, and check and transmit the measured results of the ambient dose rate and radioactivity. In addition, a collimator, which can control the inner radius, and the airborne dust sampler, which consists of an air filter and charcoal filter, were developed and mounted to the developed CZT detector for the quick and efficient response of a nuclear accident. The hand-held CZT detector was developed to make the in-situ gamma-ray spectrometry and its performance was checked to have a good energy resolution. In addition, the collimator and the airborne dust sampler were developed and mounted to the developed CZT detector for a quick and efficient response to a nuclear accident.

  17. Visual Search and Target Cueing: A Comparison of Head-Mounted Versus Hand-Held Displays on the Allocation of Visual Attention

    National Research Council Canada - National Science Library

    Yeh, Michelle; Wickens, Christopher D

    1998-01-01

    We conducted a study to examine the effects of target cueing and conformality with a hand-held or head-mounted display to determine their effects on visual search tasks requiring focused and divided attention...

  18. Comparison of maximal voluntary isometric contraction and hand-held dynamometry in measuring muscle strength of patients with progressive lower motor neuron syndrome

    NARCIS (Netherlands)

    Visser, J.; Mans, E.; de Visser, M.; van den Berg-Vos, R. M.; Franssen, H.; de Jong, J. M. B. V.; van den Berg, L. H.; Wokke, J. H. J.; de Haan, R. J.

    2003-01-01

    Context. Maximal voluntary isometric contraction, a method quantitatively assessing muscle strength, has proven to be reliable, accurate and sensitive in amyotrophic lateral sclerosis. Hand-held dynamometry is less expensive and more quickly applicable than maximal voluntary isometric contraction.

  19. Hand-held cell phone use while driving legislation and observed driver behavior among population sub-groups in the United States.

    Science.gov (United States)

    Rudisill, Toni M; Zhu, Motao

    2017-05-12

    Cell phone use behaviors are known to vary across demographic sub-groups and geographic locations. This study examined whether universal hand-held calling while driving bans were associated with lower road-side observed hand-held cell phone conversations across drivers of different ages (16-24, 25-59, ≥60 years), sexes, races (White, African American, or other), ruralities (suburban, rural, or urban), and regions (Northeast, Midwest, South, and West). Data from the 2008-2013 National Occupant Protection Use Survey were merged with states' cell phone use while driving legislation. The exposure was presence of a universal hand-held cell phone ban at time of observation. Logistic regression was used to assess the odds of drivers having a hand-held cell phone conversation. Sub-groups differences were assessed using models with interaction terms. When universal hand-held cell phone bans were effective, hand-held cell phone conversations were lower across all driver demographic sub-groups and regions. Sub-group differences existed among the sexes (p-value, phone bans, the adjusted odds ratio (aOR) of a driver hand-held phone conversation was 0.34 [95% confidence interval (CI): 0.28, 0.41] for females versus 0.47 (CI 0.40, 0.55) for males and 0.31 (CI 0.25, 0.38) for drivers in Western states compared to 0.47 (CI 0.30, 0.72) in the Northeast and 0.50 (CI 0.38, 0.66) in the South. The presence of universal hand-held cell phone bans were associated lower hand-held cell phone conversations across all driver sub-groups and regions. Hand-held phone conversations were particularly lower among female drivers and those from Western states when these bans were in effect. Public health interventions concerning hand-held cell phone use while driving could reasonably target all drivers.

  20. Hand-held cell phone use while driving legislation and observed driver behavior among population sub-groups in the United States

    OpenAIRE

    Rudisill, Toni M.; Zhu, Motao

    2017-01-01

    Abstract Background Cell phone use behaviors are known to vary across demographic sub-groups and geographic locations. This study examined whether universal hand-held calling while driving bans were associated with lower road-side observed hand-held cell phone conversations across drivers of different ages (16–24, 25–59, ≥60 years), sexes, races (White, African American, or other), ruralities (suburban, rural, or urban), and regions (Northeast, Midwest, South, and West). Methods Data from the...

  1. Drift from the Use of Hand-Held Knapsack Pesticide Sprayers in Boyacá (Colombian Andes).

    Science.gov (United States)

    García-Santos, Glenda; Feola, Giuseppe; Nuyttens, David; Diaz, Jaime

    2016-05-25

    Offsite pesticide losses in tropical mountainous regions have been little studied. One example is measuring pesticide drift soil deposition, which can support pesticide risk assessment for surface water, soil, bystanders, and off-target plants and fauna. This is considered a serious gap, given the evidence of pesticide-related poisoning in those regions. Empirical data of drift deposition of a pesticide surrogate, Uranine tracer, within one of the highest potato-producing regions in Colombia, characterized by small plots and mountain orography, is presented. High drift values encountered in this study reflect the actual spray conditions using hand-held knapsack sprayers. Comparison between measured and predicted drift values using three existing empirical equations showed important underestimation. However, after their optimization based on measured drift information, the equations showed a strong predictive power for this study area and the study conditions. The most suitable curve to assess mean relative drift was the IMAG calculator after optimization.

  2. Hand-held multi-DOF robotic forceps for neurosurgery designed for dexterous manipulation in deep and narrow space.

    Science.gov (United States)

    Okubo, Takuro; Harada, Kanako; Fujii, Masahiro; Tanaka, Shinichi; Ishimaru, Tetsuya; Iwanaka, Tadashi; Nakatomi, Hirohumi; Sora, Sigeo; Morita, Akio; Sugita, Naohiko; Mitsuishi, Mamoru

    2014-01-01

    Neurosurgical procedures require precise and dexterous manipulation of a surgical suture in narrow and deep spaces in the brain. This is necessary for surgical tasks such as the anastomosis of microscopic blood vessels and dura mater suturing. A hand-held multi-degree of freedom (DOF) robotic forceps was developed to aid the performance of such difficult tasks. The diameter of the developed robotic forceps is 3.5 mm, and its tip has three DOFs, namely, bending, rotation, and grip. Experimental results showed that the robotic forceps had an average needle insertion force of 1.7 N. Therefore, an increase in the needle insertion force is necessary for practical application of the developed device.

  3. 3D Scan of Ornamental Column (huabiao Using Terrestrial LiDAR and Hand-held Imager

    Directory of Open Access Journals (Sweden)

    W. Zhang

    2015-08-01

    Full Text Available In ancient China, Huabiao was a type of ornamental column used to decorate important buildings. We carried out 3D scan of a Huabiao located in Peking University, China. This Huabiao was built no later than 1742. It is carved by white marble, 8 meters in height. Clouds and various postures of dragons are carved on its body. Two instruments were used to acquire the point cloud of this Huabiao, a terrestrial LiDAR (Riegl VZ-1000 and a hand-held imager (Mantis Vision F5. In this paper, the details of the experiment were described, including the differences between these two instruments, such as working principle, spatial resolution, accuracy, instrument dimension and working flow. The point clouds obtained respectively by these two instruments were compared, and the registered point cloud of Huabiao was also presented. These should be of interest and helpful for the research communities of archaeology and heritage.

  4. Assessment of Lower Limb Muscle Strength and Power Using Hand-Held and Fixed Dynamometry: A Reliability and Validity Study

    Science.gov (United States)

    Perraton, Luke G.; Bower, Kelly J.; Adair, Brooke; Pua, Yong-Hao; Williams, Gavin P.; McGaw, Rebekah

    2015-01-01

    Introduction Hand-held dynamometry (HHD) has never previously been used to examine isometric muscle power. Rate of force development (RFD) is often used for muscle power assessment, however no consensus currently exists on the most appropriate method of calculation. The aim of this study was to examine the reliability of different algorithms for RFD calculation and to examine the intra-rater, inter-rater, and inter-device reliability of HHD as well as the concurrent validity of HHD for the assessment of isometric lower limb muscle strength and power. Methods 30 healthy young adults (age: 23±5yrs, male: 15) were assessed on two sessions. Isometric muscle strength and power were measured using peak force and RFD respectively using two HHDs (Lafayette Model-01165 and Hoggan microFET2) and a criterion-reference KinCom dynamometer. Statistical analysis of reliability and validity comprised intraclass correlation coefficients (ICC), Pearson correlations, concordance correlations, standard error of measurement, and minimal detectable change. Results Comparison of RFD methods revealed that a peak 200ms moving window algorithm provided optimal reliability results. Intra-rater, inter-rater, and inter-device reliability analysis of peak force and RFD revealed mostly good to excellent reliability (coefficients ≥ 0.70) for all muscle groups. Concurrent validity analysis showed moderate to excellent relationships between HHD and fixed dynamometry for the hip and knee (ICCs ≥ 0.70) for both peak force and RFD, with mostly poor to good results shown for the ankle muscles (ICCs = 0.31–0.79). Conclusions Hand-held dynamometry has good to excellent reliability and validity for most measures of isometric lower limb strength and power in a healthy population, particularly for proximal muscle groups. To aid implementation we have created freely available software to extract these variables from data stored on the Lafayette device. Future research should examine the reliability

  5. Calculation of induced current densities and specific absorption rates (SAR) for pregnant women exposed to hand-held metal detectors

    International Nuclear Information System (INIS)

    Kainz, Wolfgang; Chan, Dulciana D; Casamento, Jon P; Bassen, Howard I

    2003-01-01

    The finite difference time domain (FDTD) method in combination with a well established frequency scaling method was used to calculate the internal fields and current densities induced in a simple model of a pregnant woman and her foetus, when exposed to hand-held metal detectors. The pregnant woman and foetus were modelled using a simple semi-heterogeneous model in 10 mm resolution, consisting of three different types of tissue. The model is based on the scanned shape of a pregnant woman in the 34th gestational week. Nine different representative models of hand-held metal detectors operating in the frequency range from 8 kHz to 2 MHz were evaluated. The metal detectors were placed directly on the abdomen of the computational model with a spacing of 1 cm. Both the induced current density and the specific absorption rate (SAR) are well below the recommended limits for exposure of the general public published in the ICNIRP Guidelines and the IEEE C95.1 Standard. The highest current density is 8.3 mA m -2 and the highest SAR is 26.5 μW kg -1 . Compared to the limits for the induced current density recommended in the ICNIRP Guidelines, a minimum safety factor of 3 exists. Compared to the IEEE C95.1 Standard, a safety factor of 60,000 for the specific absorption rate was found. Based on the very low specific absorption rate and an induced current density below the recommended exposure limits, significant temperature rise or nerve stimulation in the pregnant woman or in the foetus can be excluded

  6. Hand-held tidal breathing nasal nitric oxide measurement--a promising targeted case-finding tool for the diagnosis of primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Marthin, June Kehlet; Nielsen, Kim Gjerum

    2013-01-01

    BACKGROUND: Nasal nitric oxide (nNO) measurement is an established first line test in the work-up for primary ciliary dyskinesia (PCD). Tidal breathing nNO (TB-nNO) measurements require minimal cooperation and are potentially useful even in young children. Hand-held NO devices are becoming...... increasingly widespread for asthma management. Therefore, we chose to assess whether hand-held TB-nNO measurements reliably discriminate between PCD, and Healthy Subjects (HS) and included Cystic Fibrosis (CF) patients as a disease control group known to have intermediate nNO levels. METHODS: In this cross...... sectional, single centre, single occasion, proof-of-concept study in children and adults with PCD and CF, and in HS we compared feasibility, success rates, discriminatory capacity, repeatability and agreement between a hand-held electrochemical device equipped with a nNO software application sampling...

  7. User certification of hand-held x-ray tube based analytical fluorescent devices in a canadian context

    International Nuclear Information System (INIS)

    Maharaj, H.P.

    2005-01-01

    Safety education aims to reduce personal injury and improve well being. This health promotion principle is applied in the case of hand-held open beam x-ray tube based analytical x-ray devices. Such devices not only are light weight and portable, but also present high radiation exposure levels at the beam exit port and potentially can be used in a variety of industrial applications for determination of material composition. There is much potential for radiation risks to occur with resultant adverse effects if such devices are not used by trained individuals within controlled environments. A level of radiation safety knowledge and understanding of the device design, construction and performance characteristics appear warranted. To reduce radiation risks, user certification at a federal level was introduced in 2004 based on International Standards Organization 20807, since that standard comprises elements commensurate with risk reduction strategies. Within these contexts, a federally certified user is deemed to have acquired a level of safety knowledge and skills to facilitate safe use of the device. Certification, however, does not absolve the holder from obligations of compliance with applicable provincial, territorial or federal laws respecting device operation. The union of federal certification and applicable legislative mandated operational criteria reduces radiation risks overall. (author)

  8. Forest Inventory with Terrestrial LiDAR: A Comparison of Static and Hand-Held Mobile Laser Scanning

    Directory of Open Access Journals (Sweden)

    Sébastien Bauwens

    2016-06-01

    Full Text Available The application of static terrestrial laser scanning (TLS in forest inventories is becoming more effective. Nevertheless, the occlusion effect is still limiting the processing efficiency to extract forest attributes. The use of a mobile laser scanner (MLS would reduce this occlusion. In this study, we assessed and compared a hand-held mobile laser scanner (HMLS with two TLS approaches (single scan: SS, and multi scan: MS for the estimation of several forest parameters in a wide range of forest types and structures. We found that SS is competitive to extract the ground surface of forest plots, while MS gives the best result to describe the upper part of the canopy. The whole cross-section at 1.3 m height is scanned for 91% of the trees (DBH > 10 cm with the HMLS leading to the best results for DBH estimates (bias of −0.08 cm and RMSE of 1.11 cm, compared to no fully-scanned trees for SS and 42% fully-scanned trees for MS. Irregularities, such as bark roughness and non-circular cross-section may explain the negative bias encountered for all of the scanning approaches. The success of using MLS in forests will allow for 3D structure acquisition on a larger scale and in a time-efficient manner.

  9. Comparison of a digital and an optical analogue hand-held refractometer for the measurement of canine urine specific gravity.

    Science.gov (United States)

    Paris, J K; Bennett, A D; Dodkin, S J; Gunn-Moore, D A

    2012-05-05

    Urine specific gravity (USG) is used clinically as a measure of urine concentration, and is routinely assessed by refractometry. A comparison between optical analogue and digital refractometers for evaluation of canine urine has not been reported. The aim of this study was to compare a digital and an optical analogue hand-held refractometer for the measurement of canine USG, and to assess correlation with urine osmolality. Prospective study. Free-catch urine samples were collected from 285 hospitalised adult dogs, and paired USG readings were obtained with a digital and an optical analogue refractometer. In 50 dogs, urine osmolality was also measured using a freezing point depression osmometer. There was a small but statistically significant difference between the two refractometers (P<0.001), with the optical analogue refractometer reading higher than the digital refractometer (mean difference 0.0006, sd 0.0012). Paired refractometer measurements varied by <0.002 in 91.5 per cent of cases. The optical analogue and digital refractometer readings showed excellent correlation with osmolality (r=0.980 and r=0.977, respectively, P<0.001 in both cases). Despite statistical significance, the difference between the two refractometers is unlikely to be clinically significant. Both instruments provide an accurate assessment of USG in dogs.

  10. Validation of Ankle Strength Measurements by Means of a Hand-Held Dynamometer in Adult Healthy Subjects

    Directory of Open Access Journals (Sweden)

    Andrea Ancillao

    2017-01-01

    Full Text Available Uniaxial Hand-Held Dynamometer (HHD is a low-cost device widely adopted in clinical practice to measure muscle force. HHD measurements depend on operator’s ability and joint movements. The aim of the work is to validate the use of a commercial HHD in both dorsiflexion and plantarflexion ankle strength measurements quantifying the effects of HHD misplacements and unwanted foot’s movements on the measurements. We used an optoelectronic system and a multicomponent load cell to quantify the sources of error in the manual assessment of the ankle strength due to both the operator’s ability to hold still the HHD and the transversal components of the exerted force that are usually neglected in clinical routine. Results showed that foot’s movements and angular misplacements of HHD on sagittal and horizontal planes were relevant sources of inaccuracy on the strength assessment. Moreover, ankle dorsiflexion and plantarflexion force measurements presented an inaccuracy less than 2% and higher than 10%, respectively. In conclusion, the manual use of a uniaxial HHD is not recommended for the assessment of ankle plantarflexion strength; on the contrary, it can be allowed asking the operator to pay strong attention to the HHD positioning in ankle dorsiflexion strength measurements.

  11. Characterization of a high performance ultra-thin heat pipe cooling module for mobile hand held electronic devices

    Science.gov (United States)

    Ahamed, Mohammad Shahed; Saito, Yuji; Mashiko, Koichi; Mochizuki, Masataka

    2017-11-01

    In recent years, heat pipes have been widely used in various hand held mobile electronic devices such as smart phones, tablet PCs, digital cameras. With the development of technology these devices have different user friendly features and applications; which require very high clock speeds of the processor. In general, a high clock speed generates a lot of heat, which needs to be spreaded or removed to eliminate the hot spot on the processor surface. However, it is a challenging task to achieve proper cooling of such electronic devices mentioned above because of their confined spaces and concentrated heat sources. Regarding this challenge, we introduced an ultra-thin heat pipe; this heat pipe consists of a special fiber wick structure named as "Center Fiber Wick" which can provide sufficient vapor space on the both sides of the wick structure. We also developed a cooling module that uses this kind of ultra-thin heat pipe to eliminate the hot spot issue. This cooling module consists of an ultra-thin heat pipe and a metal plate. By changing the width, the flattened thickness and the effective length of the ultra-thin heat pipe, several experiments have been conducted to characterize the thermal properties of the developed cooling module. In addition, other experiments were also conducted to determine the effects of changes in the number of heat pipes in a single module. Characterization and comparison of the module have also been conducted both experimentally and theoretically.

  12. Intrarater reliability of hand held dynamometry in measuring lower extremity isometric strength using a portable stabilization device.

    Science.gov (United States)

    Jackson, Steven M; Cheng, M Samuel; Smith, A Russell; Kolber, Morey J

    2017-02-01

    Hand held dynamometry (HHD) is a more objective way to quantify muscle force production (MP) compared to traditional manual muscle testing. HHD reliability can be negatively impacted by both the strength of the tester and the subject particularly in the lower extremities due to larger muscle groups. The primary aim of this investigation was to assess intrarater reliability of HHD with use of a portable stabilization device for lower extremity MP in an athletic population. Isometric lower extremity strength was measured for bilateral lower extremities including hip abductors, external rotators, adductors, knee extensors, and ankle plantar flexors was measured in a sample of healthy recreational runners (8 male, 7 females, = 30 limbs) training for a marathon. These measurements were assessed using an intrasession intrarater reliability design. Intraclass correlation coefficients (ICC) were calculated using 3,1 model based on the single rater design. The standard error of measurement (SEM) for each muscle group was also calculated. ICC were excellent ranging from ICC (3,1) = 0.93-0.98 with standard error of measurements ranging from 0.58 to 17.2 N. This study establishes the use of a HHD with a portable stabilization device as demonstrating good reliability within testers for measuring lower extremity muscle performance in an active healthy population. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Four dimensional hybrid ultrasound and optoacoustic imaging via passive element optical excitation in a hand-held probe

    Energy Technology Data Exchange (ETDEWEB)

    Fehm, Thomas Felix; Razansky, Daniel, E-mail: dr@tum.de [Institute for Biological and Medical Imaging (IBMI), Helmholtz Zentrum München, Neuherberg (Germany); Faculty of Medicine, Technische Universität München, Munich (Germany); Deán-Ben, Xosé Luís [Institute for Biological and Medical Imaging (IBMI), Helmholtz Zentrum München, Neuherberg (Germany)

    2014-10-27

    Ultrasonography and optoacoustic imaging share powerful advantages related to the natural aptitude for real-time image rendering with high resolution, the hand-held operation, and lack of ionizing radiation. The two methods also possess very different yet highly complementary advantages of the mechanical and optical contrast in living tissues. Nonetheless, efficient integration of these modalities remains challenging owing to the fundamental differences in the underlying physical contrast, optimal signal acquisition, and image reconstruction approaches. We report on a method for hybrid acquisition and reconstruction of three-dimensional pulse-echo ultrasound and optoacoustic images in real time based on passive ultrasound generation with an optical absorber, thus avoiding the hardware complexity of active ultrasound generation. In this way, complete hybrid datasets are generated with a single laser interrogation pulse, resulting in simultaneous rendering of ultrasound and optoacoustic images at an unprecedented rate of 10 volumetric frames per second. Performance is subsequently showcased in phantom experiments and in-vivo measurements from a healthy human volunteer, confirming general clinical applicability of the method.

  14. Effects of a new mild shampoo for preventing hair loss in Asian by a simple hand-held phototrichogram technique.

    Science.gov (United States)

    Baek, J H; Lee, S Y; Yoo, M; Park, W-S; Lee, S J; Boo, Y C; Koh, J-S

    2011-12-01

    This study was conducted to evaluate the effects of a commercially available shampoo in Korean subjects with alopecia using a simple hand-held phototrichogram technique. Forty-four subjects with alopecia were enrolled and forty subjects continued for 16 weeks. In the test group, total hair counts increased significantly at weeks 8 and 16, and the number of shedding hair significantly decreased at week 16. Terminal hair counts significantly increased at week 8. In the control group, hair thickness and the number of vellus hairs significantly decreased at week 16. The number of total hairs significantly increased in the test group than in the control group at weeks 8 and 16. The number of shedding hairs significantly decreased in the test group than in the control group at week 16. Visual assessment using clinical digital images showed that the number of total hairs appeared to increase although there was no statistical significance. In this study, it was found that the test shampoo could prevent hair loss. © 2011 DERMAPRO Co Ltd. ICS © 2011 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  15. Four dimensional hybrid ultrasound and optoacoustic imaging via passive element optical excitation in a hand-held probe

    Science.gov (United States)

    Fehm, Thomas Felix; Deán-Ben, Xosé Luís; Razansky, Daniel

    2014-10-01

    Ultrasonography and optoacoustic imaging share powerful advantages related to the natural aptitude for real-time image rendering with high resolution, the hand-held operation, and lack of ionizing radiation. The two methods also possess very different yet highly complementary advantages of the mechanical and optical contrast in living tissues. Nonetheless, efficient integration of these modalities remains challenging owing to the fundamental differences in the underlying physical contrast, optimal signal acquisition, and image reconstruction approaches. We report on a method for hybrid acquisition and reconstruction of three-dimensional pulse-echo ultrasound and optoacoustic images in real time based on passive ultrasound generation with an optical absorber, thus avoiding the hardware complexity of active ultrasound generation. In this way, complete hybrid datasets are generated with a single laser interrogation pulse, resulting in simultaneous rendering of ultrasound and optoacoustic images at an unprecedented rate of 10 volumetric frames per second. Performance is subsequently showcased in phantom experiments and in-vivo measurements from a healthy human volunteer, confirming general clinical applicability of the method.

  16. Four dimensional hybrid ultrasound and optoacoustic imaging via passive element optical excitation in a hand-held probe

    International Nuclear Information System (INIS)

    Fehm, Thomas Felix; Razansky, Daniel; Deán-Ben, Xosé Luís

    2014-01-01

    Ultrasonography and optoacoustic imaging share powerful advantages related to the natural aptitude for real-time image rendering with high resolution, the hand-held operation, and lack of ionizing radiation. The two methods also possess very different yet highly complementary advantages of the mechanical and optical contrast in living tissues. Nonetheless, efficient integration of these modalities remains challenging owing to the fundamental differences in the underlying physical contrast, optimal signal acquisition, and image reconstruction approaches. We report on a method for hybrid acquisition and reconstruction of three-dimensional pulse-echo ultrasound and optoacoustic images in real time based on passive ultrasound generation with an optical absorber, thus avoiding the hardware complexity of active ultrasound generation. In this way, complete hybrid datasets are generated with a single laser interrogation pulse, resulting in simultaneous rendering of ultrasound and optoacoustic images at an unprecedented rate of 10 volumetric frames per second. Performance is subsequently showcased in phantom experiments and in-vivo measurements from a healthy human volunteer, confirming general clinical applicability of the method.

  17. Maximal isometric muscle strength values obtained By hand-held dynamometry in children between 6 and 15 years of age.

    Science.gov (United States)

    Escobar, Raul G; Munoz, Karin T; Dominguez, Angelica; Banados, Pamela; Bravo, Maria J

    2017-01-01

    In this study we aimed to determine the maximal isometric muscle strength of a healthy, normal-weight, pediatric population between 6 and 15 years of age using hand-held dynamometry to establish strength reference values. The secondary objective was determining the relationship between strength and anthropometric parameters. Four hundred normal-weight Chilean children, split into 10 age groups, separated by 1-year intervals, were evaluated. Each age group included between 35 and 55 children. The strength values increased with increasing age and weight, with a correlation of 0.83 for age and 0.82 for weight. The results were similar to those reported in previous studies regarding the relationships among strength, age, and anthropometric parameters, but the reported strength differed. These results provide normal strength parameters for healthy and normal-weight Chilean children between 6 and 15 years of age and highlight the relevance of ethnicity in defining reference values for muscle strength in a pediatric population. Muscle Nerve 55: 16-22, 2017. © 2016 Wiley Periodicals, Inc.

  18. Field studies on health effects from the application of two organophosphorus insecticide formulations by hand-held ULV to cotton.

    Science.gov (United States)

    Kummer, R; van Sittert, N J

    1986-10-01

    Two field studies to assess the health implications for farmers applying two different formulations containing organophosphorus (OP) pesticides to cotton by hand-held ULV are described. The first study, carried out in the Ivory Coast, involved the application of an endrin/DDT/methylparathion (MEP) formulation in an aromatic hydrocarbon solvent. The second study took place in Indonesia with a 20% monocrotophos formulation in a mixture of a glycol and a glycol ether. Both studies were carried out under actual field conditions. The purpose of the studies was to get a good assessment of the health hazards of the particular formulation, used under the specific circumstances and agronomic requirements of the area of application and taking into account all local, climatic and cultural conditions that could be of possible influence. The results showed that in both studies skin exposures took place during application and especially during handling, filling and cleaning, and that inhalation of spray mist was negligible. Absorption was confirmed by the presence in urine of metabolites of endrin and methylparathion in the Ivory Coast study, and of dimethyl phosphate in the Indonesia study. No clinical signs or symptoms of intoxication were discovered in either study, nor were inhibitions of cholinesterase (ChE) activity of health significance established under the conditions of the studies. In addition, various practical aspects such as choice of apparatus, of formulation, the application procedures etc. are discussed.

  19. X-ray film digitization using a personal computer and hand-held scanner: a simple technique for storing images

    International Nuclear Information System (INIS)

    Munoz-Nunez, C. F.; Lloret-Alcaniz, A.

    1998-01-01

    To develop a simple, low-cost technique for the digitization of X-ray films for personal use. A 66-MHz 486 PC with 8 MB of RAM, a Logitech ScanMan 256 hand-held scanner and a standard negatoscope with the power source converted to direct current. Although the system was originally designed for the digitization of mammographies, it has also been used with computed tomography, magnetic resonance, digital angiography and ultrasonographic images, as well as plain X-rays. After a minimal training period, the system digitized X-ray films easily and rapidly. Although the scanning values vary depending on the type of image to be digitized, an input spatial resolution of 200 dpi and a contrast resolution of 256 levels of gray are generally adequate. Of the storage formats tested, JPEG presented the best quality/image size ratio. A simple, low-cost technique has been developed for the digitization of X-ray films. This technique enables the storage of images in a digital format, thus facilitating their presentation and transmission. (Author) 9 refs

  20. Integrated optical detection of autonomous capillary microfluidic immunoassays:a hand-held point-of-care prototype.

    Science.gov (United States)

    Novo, P; Chu, V; Conde, J P

    2014-07-15

    The miniaturization of biosensors using microfluidics has potential in enabling the development of point-of-care devices, with the added advantages of reduced time and cost of analysis with limits-of-detection comparable to those obtained through traditional laboratory techniques. Interfacing microfluidic devices with the external world can be difficult especially in aspects involving fluid handling and the need for simple sample insertion that avoids special equipment or trained personnel. In this work we present a point-of-care prototype system by integrating capillary microfluidics with a microfabricated photodiode array and electronic instrumentation into a hand-held unit. The capillary microfluidic device is capable of autonomous and sequential fluid flow, including control of the average fluid velocity at any given point of the analysis. To demonstrate the functionality of the prototype, a model chemiluminescence ELISA was performed. The performance of the integrated optical detection in the point-of-care prototype is equal to that obtained with traditional bench-top instrumentation. The photodiode signals were acquired, displayed and processed by a simple graphical user interface using a computer connected to the microcontroller through USB. The prototype performed integrated chemiluminescence ELISA detection in about 15 min with a limit-of-detection of ≈2 nM with an antibody-antigen affinity constant of ≈2×10(7) M(-1). Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Hand held control unit for controlling a display screen-oriented computer game, and a display screen-oriented computer game having one or more such control units

    NARCIS (Netherlands)

    2001-01-01

    A hand-held control unit is used to control a display screen-oriented computer game. The unit comprises a housing with a front side, a set of control members lying generally flush with the front side for through actuating thereof controlling actions of in-game display items, and an output for

  2. Rapid and automatic chemical identification of the medicinal flower buds of Lonicera plants by the benchtop and hand-held Fourier transform infrared spectroscopy

    Science.gov (United States)

    Chen, Jianbo; Guo, Baolin; Yan, Rui; Sun, Suqin; Zhou, Qun

    2017-07-01

    With the utilization of the hand-held equipment, Fourier transform infrared (FT-IR) spectroscopy is a promising analytical technique to minimize the time cost for the chemical identification of herbal materials. This research examines the feasibility of the hand-held FT-IR spectrometer for the on-site testing of herbal materials, using Lonicerae Japonicae Flos (LJF) and Lonicerae Flos (LF) as examples. Correlation-based linear discriminant models for LJF and LF are established based on the benchtop and hand-held FT-IR instruments. The benchtop FT-IR models can exactly recognize all articles of LJF and LF. Although a few LF articles are misjudged at the sub-class level, the hand-held FT-IR models are able to exactly discriminate LJF and LF. As a direct and label-free analytical technique, FT-IR spectroscopy has great potential in the rapid and automatic chemical identification of herbal materials either in laboratories or in fields. This is helpful to prevent the spread and use of adulterated herbal materials in time.

  3. Beyond Textbook Illustrations: Hand-Held Models of Ordered DNA and Protein Structures as 3D Supplements to Enhance Student Learning of Helical Biopolymers

    Science.gov (United States)

    Jittivadhna, Karnyupha; Ruenwongsa, Pintip; Panijpan, Bhinyo

    2010-01-01

    Textbook illustrations of 3D biopolymers on printed paper, regardless of how detailed and colorful, suffer from its two-dimensionality. For beginners, computer screen display of skeletal models of biopolymers and their animation usually does not provide the at-a-glance 3D perception and details, which can be done by good hand-held models. Here, we…

  4. Intra-operative ultrasound hand-held strain imaging for the visualization of ablations produced in the liver with a toroidal HIFU transducer: first in vivo results

    Energy Technology Data Exchange (ETDEWEB)

    Chenot, J; Melodelima, D; N' Djin, W A; Souchon, Remi; Rivoire, M; Chapelon, J Y, E-mail: jeremy.chenot@inserm.f [Inserm, U556, Lyon, F-69003 (France)

    2010-06-07

    The use of hand-held ultrasound strain imaging for the intra-operative real-time visualization of HIFU (high-intensity focused ultrasound) ablations produced in the liver by a toroidal transducer was investigated. A linear 12 MHz ultrasound imaging probe was used to obtain radiofrequency signals. Using a fast cross-correlation algorithm, strain images were calculated and displayed at 60 frames s{sup -1}, allowing the use of hand-held strain imaging intra-operatively. Fourteen HIFU lesions were produced in four pigs. Intra-operative strain imaging of HIFU ablations in the liver was feasible owing to the high frame rate. The correlation between dimensions measured on gross pathology and dimensions measured on B-mode images and on strain images were R = 0.72 and R = 0.94 respectively. The contrast between ablated and non-ablated tissue was significantly higher (p < 0.05) in the strain images (22 dB) than in the B-mode images (9 dB). Strain images allowed equivalent or improved definition of ablated regions when compared with B-mode images. Real-time intra-operative hand-held strain imaging seems to be a promising complement to conventional B-mode imaging for the guidance of HIFU ablations produced in the liver during an open procedure. These results support that hand-held strain imaging outperforms conventional B-mode ultrasound and could potentially be used for the assessment of thermal therapies.

  5. Hip- and knee-strength assessments using a hand-held dynamometer with external belt-fixation are inter-tester reliable

    DEFF Research Database (Denmark)

    Thorborg, Kristian; Bandholm, Thomas; Hölmich, Per

    2013-01-01

    PURPOSE: In football, ice-hockey, and track and field, injuries have been predicted, and hip- and knee-strength deficits quantified using hand-held dynamometry (HHD). However, systematic bias exists when testers of different sex and strength perform the measurements. Belt-fixation of the dynamome...

  6. Inter-Tester Reliability and Precision of Manual Muscle Testing and Hand-Held Dynamometry in Lower Limb Muscles of Children with Spina Bifida

    Science.gov (United States)

    Mahony, Kate; Hunt, Adrienne; Daley, Deborah; Sims, Susan; Adams, Roger

    2009-01-01

    Reliability and measurement precision of manual muscle testing (MMT) and hand-held dynamometry (HHD) were compared for children with spina bifida. Strength measures were obtained of the hip flexors, hip abductors, and knee extensors of 20 children (10 males, 10 females; mean age 9 years 10 months; range: 5 to 15 years) by two experienced physical…

  7. SEGMENTATION OF ENVIRONMENTAL TIME LAPSE IMAGE SEQUENCES FOR THE DETERMINATION OF SHORE LINES CAPTURED BY HAND-HELD SMARTPHONE CAMERAS

    Directory of Open Access Journals (Sweden)

    M. Kröhnert

    2017-09-01

    Full Text Available The relevance of globally environmental issues gains importance since the last years with still rising trends. Especially disastrous floods may cause in serious damage within very short times. Although conventional gauging stations provide reliable information about prevailing water levels, they are highly cost-intensive and thus just sparsely installed. Smartphones with inbuilt cameras, powerful processing units and low-cost positioning systems seem to be very suitable wide-spread measurement devices that could be used for geo-crowdsourcing purposes. Thus, we aim for the development of a versatile mobile water level measurement system to establish a densified hydrological network of water levels with high spatial and temporal resolution. This paper addresses a key issue of the entire system: the detection of running water shore lines in smartphone images. Flowing water never appears equally in close-range images even if the extrinsics remain unchanged. Its non-rigid behavior impedes the use of good practices for image segmentation as a prerequisite for water line detection. Consequently, we use a hand-held time lapse image sequence instead of a single image that provides the time component to determine a spatio-temporal texture image. Using a region growing concept, the texture is analyzed for immutable shore and dynamic water areas. Finally, the prevalent shore line is examined by the resultant shapes. For method validation, various study areas are observed from several distances covering urban and rural flowing waters with different characteristics. Future work provides a transformation of the water line into object space by image-to-geometry intersection.

  8. Eccentric and isometric shoulder rotator cuff strength testing using a hand-held dynamometer: reference values for overhead athletes.

    Science.gov (United States)

    Cools, Ann M J; Vanderstukken, Fran; Vereecken, Frédéric; Duprez, Mattias; Heyman, Karel; Goethals, Nick; Johansson, Fredrik

    2016-12-01

    In order to provide science-based guidelines for injury prevention or return to play, regular measurement of isometric and eccentric internal (IR) and external (ER) rotator strength is warranted in overhead athletes. However, up to date, no normative database exists regarding these values, when measured with a hand-held dynamometer. Therefore, the purpose of the study was to provide a normative database on isometric and eccentric rotator cuff (RC) strength values in a sample of overhead athletes, and to discuss gender, age and sports differences. A HHD was used to measure RC strength in 201 overhead athletes between 18 and 50 years old from three different sports disciplines: tennis, volleyball and handball. Isometric as well as eccentric strength was measured in different shoulder positions. Outcome variables of interest were isometric ER and IR strength, eccentric ER strength, and intermuscular strength ratios ER/IR. Our results show significant side, gender and sports discipline differences in the isometric and eccentric RC strength. However, when normalized to body weight, gender differences often are absent. In general, strength differences are in favour of the dominant side, the male athletes and handball. Intermuscular ER/IR ratios showed gender, sports, and side differences. This normative database is necessary to help the clinician in the evaluation of RC strength in healthy and injured overhead athletes. In view of the preventive screening and return-to-play decisions in overhead athletes, normalization to body weight and calculating intermuscular ratios are key points in this evaluation. Diagnostic study, Level III.

  9. A simple hand-held magnet array for efficient and reproducible SABRE hyperpolarisation using manual sample shaking.

    Science.gov (United States)

    Richardson, Peter M; Jackson, Scott; Parrott, Andrew J; Nordon, Alison; Duckett, Simon B; Halse, Meghan E

    2018-07-01

    Signal amplification by reversible exchange (SABRE) is a hyperpolarisation technique that catalytically transfers nuclear polarisation from parahydrogen, the singlet nuclear isomer of H 2 , to a substrate in solution. The SABRE exchange reaction is carried out in a polarisation transfer field (PTF) of tens of gauss before transfer to a stronger magnetic field for nuclear magnetic resonance (NMR) detection. In the simplest implementation, polarisation transfer is achieved by shaking the sample in the stray field of a superconducting NMR magnet. Although convenient, this method suffers from limited reproducibility and cannot be used with NMR spectrometers that do not have appreciable stray fields, such as benchtop instruments. Here, we use a simple hand-held permanent magnet array to provide the necessary PTF during sample shaking. We find that the use of this array provides a 25% increase in SABRE enhancement over the stray field approach, while also providing improved reproducibility. Arrays with a range of PTFs were tested, and the PTF-dependent SABRE enhancements were found to be in excellent agreement with comparable experiments carried out using an automated flow system where an electromagnet is used to generate the PTF. We anticipate that this approach will improve the efficiency and reproducibility of SABRE experiments carried out using manual shaking and will be particularly useful for benchtop NMR, where a suitable stray field is not readily accessible. The ability to construct arrays with a range of PTFs will also enable the rapid optimisation of SABRE enhancement as function of PTF for new substrate and catalyst systems. © 2017 The Authors Magnetic Resonance in Chemistry Published by John Wiley & Sons Ltd.

  10. A hand-held imaging probe for radio-guided surgery: physical performance and preliminary clinical experience

    International Nuclear Information System (INIS)

    Pitre, S.; Menard, L.; Charon, Y.; Solal, M.; Garbay, J.R.

    2003-01-01

    Improvements in the specificity of radiopharmaceutical compounds have been paralleled by an upsurge of interest in developing small detectors to assist surgeons in localizing tumour tissue during surgery. This study reports the main technical features and physical characteristics of a new hand-held gamma camera dedicated to accurate and real-time intra-operative imaging. First clinical experience is also reported. The POCI (Per-operative Compact Imager) camera consists of a head module composed of a high-resolution interchangeable lead collimator and a CsI(Na) crystal plate optically coupled to an intensified position-sensitive diode. The current prototype has a 40-mm diameter field of view, an outer diameter of 9.5 cm, a length of 9 cm and a weight of 1.2 kg. Overall detector imaging characteristics were evaluated by technetium-99m phantom measurements. Three patients with breast cancer previously scheduled to undergo sentinel lymph node detection were selected for the preliminary clinical experience. Preoperative images of the lymphatic basin obtained using the POCI camera were compared with conventional transcutaneous explorations using a non-imaging gamma probe. The full-width at half-maximum (FWHM) spatial resolution was investigated in both air and scattering medium; when the phantom was placed in contact with the collimator, the POCI camera exhibited a 3.2 mm FWHM. The corresponding sensitivity was 290 cps/MBq. The preliminary clinical results showed that POCI was able to predict the number and location of all SLNs. In one case, two deep radioactive nodes missed by the gamma probe were detected on the intra-operative images. This very initial experience demonstrates that the physical performance of the POCI camera is adequate for radio-guided surgery. These results are sufficiently encouraging to prompt further evaluation studies designed to determine the specific and optimal clinical role of intra-operative imaging devices

  11. Segmentation of Environmental Time Lapse Image Sequences for the Determination of Shore Lines Captured by Hand-Held Smartphone Cameras

    Science.gov (United States)

    Kröhnert, M.; Meichsner, R.

    2017-09-01

    The relevance of globally environmental issues gains importance since the last years with still rising trends. Especially disastrous floods may cause in serious damage within very short times. Although conventional gauging stations provide reliable information about prevailing water levels, they are highly cost-intensive and thus just sparsely installed. Smartphones with inbuilt cameras, powerful processing units and low-cost positioning systems seem to be very suitable wide-spread measurement devices that could be used for geo-crowdsourcing purposes. Thus, we aim for the development of a versatile mobile water level measurement system to establish a densified hydrological network of water levels with high spatial and temporal resolution. This paper addresses a key issue of the entire system: the detection of running water shore lines in smartphone images. Flowing water never appears equally in close-range images even if the extrinsics remain unchanged. Its non-rigid behavior impedes the use of good practices for image segmentation as a prerequisite for water line detection. Consequently, we use a hand-held time lapse image sequence instead of a single image that provides the time component to determine a spatio-temporal texture image. Using a region growing concept, the texture is analyzed for immutable shore and dynamic water areas. Finally, the prevalent shore line is examined by the resultant shapes. For method validation, various study areas are observed from several distances covering urban and rural flowing waters with different characteristics. Future work provides a transformation of the water line into object space by image-to-geometry intersection.

  12. Maintaining radiation exposures as low as reasonably achievable (ALARA) for dental personnel operating portable hand-held x-ray equipment.

    Science.gov (United States)

    McGiff, Thomas J; Danforth, Robert A; Herschaft, Edward E

    2012-08-01

    Clinical experience indicates that newly available portable hand-held x-ray units provide advantages compared to traditional fixed properly installed and operated x-ray units in dental radiography. However, concern that hand-held x-ray units produce higher operator doses than fixed x-ray units has caused regulatory agencies to mandate requirements for use of hand-held units that go beyond those recommended by the manufacturer and can discourage the use of this technology. To assess the need for additional requirements, a hand-held x-ray unit and a pair of manikins were used to measure the dose to a simulated operator under two conditions: exposures made according to the manufacturer's recommendations and exposures made according to manufacturer's recommendation except for the removal of the x-ray unit's protective backscatter shield. Dose to the simulated operator was determined using an array of personal dosimeters and a pair of pressurized ion chambers. The results indicate that the dose to an operator of this equipment will be less than 0.6 mSv y⁻¹ if the device is used according to the manufacturer's recommendations. This suggests that doses to properly trained operators of well-designed, hand-held dental x-ray units will be below 1.0 mSv y⁻¹ (2% of the annual occupational dose limit) even if additional no additional operational requirements are established by regulatory agencies. This level of annual dose is similar to those reported as typical dental personnel using fixed x-ray units and appears to satisfy the ALARA principal for this class of occupational exposures.

  13. Evaluation of a focussed protocol for hand-held echocardiography and computer-assisted auscultation in detecting latent rheumatic heart disease in scholars.

    Science.gov (United States)

    Zühlke, Liesl J; Engel, Mark E; Nkepu, Simpiwe; Mayosi, Bongani M

    2016-08-01

    Introduction Echocardiography is the diagnostic test of choice for latent rheumatic heart disease. The utility of echocardiography for large-scale screening is limited by high cost, complex diagnostic protocols, and time to acquire multiple images. We evaluated the performance of a brief hand-held echocardiography protocol and computer-assisted auscultation in detecting latent rheumatic heart disease with or without pathological murmur. A total of 27 asymptomatic patients with latent rheumatic heart disease based on the World Heart Federation criteria and 66 healthy controls were examined by standard cardiac auscultation to detect pathological murmur. Hand-held echocardiography using a focussed protocol that utilises one view - that is, the parasternal long-axis view - and one measurement - that is, mitral regurgitant jet - and a computer-assisted auscultation utilising an automated decision tool were performed on all patients. The sensitivity and specificity of computer-assisted auscultation in latent rheumatic heart disease were 4% (95% CI 1.0-20.4%) and 93.7% (95% CI 84.5-98.3%), respectively. The sensitivity and specificity of the focussed hand-held echocardiography protocol for definite rheumatic heart disease were 92.3% (95% CI 63.9-99.8%) and 100%, respectively. The test reliability of hand-held echocardiography was 98.7% for definite and 94.7% for borderline disease, and the adjusted diagnostic odds ratios were 1041 and 263.9 for definite and borderline disease, respectively. Computer-assisted auscultation has extremely low sensitivity but high specificity for pathological murmur in latent rheumatic heart disease. Focussed hand-held echocardiography has fair sensitivity but high specificity and diagnostic utility for definite or borderline rheumatic heart disease in asymptomatic patients.

  14. A new approach for the screening of carotid lesions: a 'fast-track' method with the use of new generation hand-held ultrasound devices.

    Science.gov (United States)

    Aboyans, V; Lacroix, P; Jeannicot, A; Guilloux, J; Bertin, F; Laskar, M

    2004-09-01

    We assessed the usefulness of fast-track neck sonography with a new-generation hand-held ultrasound scanner in the detection of > or =60% carotid stenosis. Patients with a past history of atherosclerotic disease or presence of risk factors were enrolled. All had fast-track carotid screening with a hand-held ultrasound scanner. Initial assessment was performed with our quick imaging protocol. A second examiner performed a conventional complete carotid duplex as gold-standard. We enrolled 197 consecutive patients with a mean age of 67 years (range 35-94). A carotid stenosis >60% was detected in 13 cases (6%). The sensitivity, specificity, positive and negative predictive value of fast-track sonography was 100%, 64%, 17% and 100%, respectively. Concomitant power Doppler imaging during the fast-track method did not improve accuracy. The use of a fast-track method with a hand-held ultrasound device can reduce the number of unnecessary carotid Duplex and enhance the screening efficiency without missing significant carotid stenoses.

  15. Ozone, spectral irradiance and aerosol measurements with the Brewer spectro radiometer; Misure di ozono, irradianza spettrale ultravioletta e aerosol con lo spettroradiometro Brewer

    Energy Technology Data Exchange (ETDEWEB)

    Marenco, F.; Di Sarra, A. [ENEA, Centro Ricerche Casaccia, Rome (Italy)

    2001-07-01

    In this technical report a detailed description of the Brewer spectro radiometer, a widespread instrument for ozone and ultraviolet radiation, is given. The methodologies used to measure these quantities and for instrument calibration are described in detail. Finally a new methodology, developed by ENEA to derive the aerosol optical depth from the Brewer routine total ozone measurements, is described. This methodology is based on Langley extrapolation, on the determination of the transmissivity of the Brewer neutral density filters, and on a statistically significant number of half days of measurements obtained in could-free conditions. Results of this method, obtained with the Brewer of the ENEA station for climate observations Roberto Sarao, located in the island of Lampedusa, are reported. These results confirm the validity of the method, thanks to independent measurements taken in 1999 with a Multi filter Rotating Shadow band Radiometer. This methodology allows researchers to obtain an aerosol climatology from ozone measurements obtained at several sites world-wide. [Italian] In questo rapporto tecnico viene fornita la descrizione dettagliata di uno strumento comunemente utilizzato per le misure di ozono e radiazione ultravioletta: lo spettroradiometro Brewer. Le metodologie usate per la misura di queste grandezze e per la calibrazione dello strumento vengono descritte in dettaglio. Infine, viene descritto una nuova metodologia, messa a punto dall'ENEA, per ricavare lo spessore ottico degli aerosol a partire dalle misure di ozono fatte normalmente dal Brewer. Questa metodologia si basa su di una calibrazione effettuata con il metodo dell' estrapolazione di Langley, sulla misura della trasmissivita' dei filtri a densita' neutra dello strumento, e su un numero statisticamente grande di mezze giornate di misure effettuate in assenza di nuvole. Sono riportati alcuni risultati della metodologia, ottenuti con il Brewer della Stazione per le

  16. Assessment of isometric muscle strength and rate of torque development with hand-held dynamometry: Test-retest reliability and relationship with gait velocity after stroke.

    Science.gov (United States)

    Mentiplay, Benjamin F; Tan, Dawn; Williams, Gavin; Adair, Brooke; Pua, Yong-Hao; Bower, Kelly J; Clark, Ross A

    2018-04-27

    Isometric rate of torque development examines how quickly force can be exerted and may resemble everyday task demands more closely than isometric strength. Rate of torque development may provide further insight into the relationship between muscle function and gait following stroke. Aims of this study were to examine the test-retest reliability of hand-held dynamometry to measure isometric rate of torque development following stroke, to examine associations between strength and rate of torque development, and to compare the relationships of strength and rate of torque development to gait velocity. Sixty-three post-stroke adults participated (60 years, 34 male). Gait velocity was assessed using the fast-paced 10 m walk test. Isometric strength and rate of torque development of seven lower-limb muscle groups were assessed with hand-held dynamometry. Intraclass correlation coefficients were calculated for reliability and Spearman's rho correlations were calculated for associations. Regression analyses using partial F-tests were used to compare strength and rate of torque development in their relationship with gait velocity. Good to excellent reliability was shown for strength and rate of torque development (0.82-0.97). Strong associations were found between strength and rate of torque development (0.71-0.94). Despite high correlations between strength and rate of torque development, rate of torque development failed to provide significant value to regression models that already contained strength. Assessment of isometric rate of torque development with hand-held dynamometry is reliable following stroke, however isometric strength demonstrated greater relationships with gait velocity. Further research should examine the relationship between dynamic measures of muscle strength/torque and gait after stroke. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Into the Wild: Neuroergonomic Differentiation of Hand-Held and Augmented Reality Wearable Displays during Outdoor Navigation with Functional Near Infrared Spectroscopy.

    Science.gov (United States)

    McKendrick, Ryan; Parasuraman, Raja; Murtza, Rabia; Formwalt, Alice; Baccus, Wendy; Paczynski, Martin; Ayaz, Hasan

    2016-01-01

    Highly mobile computing devices promise to improve quality of life, productivity, and performance. Increased situation awareness and reduced mental workload are two potential means by which this can be accomplished. However, it is difficult to measure these concepts in the "wild". We employed ultra-portable battery operated and wireless functional near infrared spectroscopy (fNIRS) to non-invasively measure hemodynamic changes in the brain's Prefrontal cortex (PFC). Measurements were taken during navigation of a college campus with either a hand-held display, or an Augmented reality wearable display (ARWD). Hemodynamic measures were also paired with secondary tasks of visual perception and auditory working memory to provide behavioral assessment of situation awareness and mental workload. Navigating with an augmented reality wearable display produced the least workload during the auditory working memory task, and a trend for improved situation awareness in our measures of prefrontal hemodynamics. The hemodynamics associated with errors were also different between the two devices. Errors with an augmented reality wearable display were associated with increased prefrontal activity and the opposite was observed for the hand-held display. This suggests that the cognitive mechanisms underlying errors between the two devices differ. These findings show fNIRS is a valuable tool for assessing new technology in ecologically valid settings and that ARWDs offer benefits with regards to mental workload while navigating, and potentially superior situation awareness with improved display design.

  18. Hand-held Raman sensor head for in-situ characterization of meat quality applying a microsystem 671 nm diode laser

    Science.gov (United States)

    Schmidt, Heinar; Sowoidnich, Kay; Maiwald, Martin; Sumpf, Bernd; Kronfeldt, Heinz-Detlef

    2009-05-01

    A hand-held Raman sensor head was developed for the in-situ characterization of meat quality. As light source, a microsystem based external cavity diode laser module (ECDL) emitting at 671 nm was integrated in the sensor head and attached to a miniaturized optical bench which contains lens optics for excitation and signal collection as well as a Raman filter stage for Rayleigh rejection. The signal is transported with an optical fiber to the detection unit which was in the initial phase a laboratory spectrometer with CCD detector. All elements of the ECDL are aligned on a micro optical bench with 13 x 4 mm2 footprint. The wavelength stability is provided by a reflection Bragg grating and the laser has an optical power of up to 200 mW. However, for the Raman measurements of meat only 35 mW are needed to obtain Raman spectra within 1 - 5 seconds. Short measuring times are essential for the hand-held device. The laser and the sensor head are characterized in terms of stability and performance for in-situ Raman investigations. The function is demonstrated in a series of measurements with raw and packaged pork meat as samples. The suitability of the Raman sensor head for the quality control of meat and other products will be discussed.

  19. Characterisation of optical filters for broadband UVA radiometer

    Science.gov (United States)

    Alves, Luciana C.; Coelho, Carla T.; Corrêa, Jaqueline S. P. M.; Menegotto, Thiago; Ferreira da Silva, Thiago; Aparecida de Souza, Muriel; Melo da Silva, Elisama; Simões de Lima, Maurício; Dornelles de Alvarenga, Ana Paula

    2016-07-01

    Optical filters were characterized in order to know its suitability for use in broadband UVA radiometer head for spectral irradiance measurements. The spectral transmittance, the angular dependence and the spatial uniformity of the spectral transmittance of the UVA optical filters were investigated. The temperature dependence of the transmittance was also studied.

  20. Wideband filter radiometers for blackbody temperature measurements

    Science.gov (United States)

    Boivin, L. P.; Bamber, C.; Gaertner, A. A.; Gerson, R. K.; Woods, D. J.; Woolliams, E. R.

    2010-10-01

    The use of high-temperature blackbody (HTBB) radiators to realize primary spectral irradiance scales requires that the operating temperature of the HTBB be accurately determined. We have developed five filter radiometers (FRs) to measure the temperature of the National Research Council of Canada's HTBB. The FRs are designed to minimize sensitivity to ambient temperature fluctuations. They incorporate air-spaced colored glass filters and a Si photodiode detector that are housed in a cell whose temperature is controlled to ±0.1°C by means of annular thermoelectric elements at the front and rear of the cell. These wideband filter radiometers operate in four different wavelength bands. The spectral responsivity measurements were performed in an underfill geometry for a power-mode calibration that is traceable to NRC's cryogenic radiometer. The spectral temperature sensitivity of each of these FRs has been measured. The apertures for these FRs were cold-formed by swaging machine-cut apertures onto precision dowel pins. A description of the filter radiometer design, fabrication and testing, together with a detailed uncertainty analysis, is presented. We derive the equations that relate the spectral irradiance measured by the FRs to the spectral radiance and temperature of the HTBB, and deal specifically with the change of index of refraction over the path of the radiation from the interior of the HTBB to the FRs. We believe these equations are more accurate than recently published derivations. Our measurements of the operating temperature of our HTBB working at temperatures near 2500 K, 2700 K and 2900 K, together with measurements using a pyrometer, show agreement between the five filter radiometers and with the pyrometer to within the estimated uncertainties.

  1. Thresholds of whole-blood β-hydroxybutyrate and glucose concentrations measured with an electronic hand-held device to identify ovine hyperketonemia.

    Science.gov (United States)

    Pichler, M; Damberger, A; Schwendenwein, I; Gasteiner, J; Drillich, M; Iwersen, M

    2014-03-01

    Metabolic disorders, especially hyperketonemia, are very common in dairy sheep. The whole-blood concentrations of β-hydroxybutyrate (BHBA) and glucose can be determined by commercially available electronic hand-held devices, which are used in human medicine and for the detection of ketosis in dairy cows. The aim of this study was to evaluate the suitability of the hand-held device Precision Xceed (PX; Abbott Diabetes Care Inc., Abbott Park, IL) to detect hyperketonemia in ewes. An additional objective of this study was to evaluate the agreement between samples obtained by minimal invasive venipuncture of an ear vein and measurements of whole-blood samples from the jugular vein (vena jugularis, v. jug.). Blood samples taken from the v. jug. were collected from 358 ewes on 4 different farms. These samples and a blood drop obtained from an ear vein were analyzed simultaneously on farm with the PX. For method comparison, the samples obtained from the v. jug. were also analyzed by standard methods, which served as the gold standard at the Central Laboratory of the University of Veterinary Medicine Vienna, Austria. The correlation coefficients between the serum BHBA concentration and the concentrations measured with the hand-held meter in the whole blood from an ear vein and the v. jug. were 0.94 and 0.96, respectively. The correlation coefficients of plasma and whole-blood glucose concentration were 0.68 for the v. jug. and 0.47 for the ear vein. The mean glucose concentration was significantly lower in animals classified as hyperketonemic (BHBA ≥ 1.6 mmol/L) compared with healthy ewes. Whole-blood concentrations of BHBA and glucose measured with the PX from v. jug. showed a constant negative bias of 0.15 mmol/L and 8.4 mg/dL, respectively. Hence, a receiver operating characteristic analysis was performed to determine thresholds for the PX to detect hyperketonemia in ewes. This resulted in thresholds for moderate ketosis of BHBA concentrations of 0.7 mmol/L in blood

  2. Suitability of capillary blood obtained by a minimally invasive lancet technique to detect subclinical ketosis in dairy cows by using 3 different electronic hand-held devices.

    Science.gov (United States)

    Kanz, P; Drillich, M; Klein-Jöbstl, D; Mair, B; Borchardt, S; Meyer, L; Schwendenwein, I; Iwersen, M

    2015-09-01

    The objective of this study was to evaluate the suitability of capillary blood obtained by a minimally invasive lancet technique to detect subclinical ketosis in 49 prepartum and 191 postpartum Holstein-Friesian cows using 3 different electronic hand-held devices [FreeStyle Precision (FSP, Abbott), GlucoMen LX Plus (GLX, A. Menarini), NovaVet (NOV, Nova Biomedical)]. The β-hydroxybutyrate (BHBA) concentration in serum harvested from coccygeal blood samples was analyzed in a laboratory and used as a reference value. Capillary samples were obtained from the skin of the exterior vulva by using 1 of 3 different lancets. In all samples, the concentration of BHBA was immediately analyzed with all 3 hand-held devices used in random order. All lancets used in the study were eligible for capillary blood collection but differed in the total number of incisions needed. Spearman correlation coefficients between the BHBA concentrations in capillary blood and the reference test were highly significant with 83% for the FSP, 73% for the NOV, and 63% for the GLX. Using capillary blood, the FSP overestimated the mean BHBA concentration compared with the reference test (+0.08 mmol/L), whereas the GLX and NOV underestimated the mean concentration (-0.07 and -0.01 mmol/L). When a BHBA concentration of 1.2 mmol/L in serum was used to define subclinical ketosis, the corresponding analyses of receiver operating characteristics resulted in optimized thresholds for capillary blood of 1.1 mmol/L for the NOV and GLX devices, and of 1.0 mmol/L for the FSP. Based on these thresholds, sensitivities (Se) and specificities (Sp) were 89 and 84% for the NOV, 80 and 89% for the GLX, and 100 and 76% for the FSP. Based on a serum BHBA concentration of 1.4 mmol/L, analyses of receiver operating characteristics resulted in optimized cut-offs of 1.4 mmol/L for the FSP (Se 100%, Sp 92%), 1.3 mmol/L for the NOV (Se 80%, Sp 95%), and 1.1 mmol/L (Se 90%, Sp 85%) for the GLX. Using these optimized thresholds

  3. Automation Study for Longhorn Army Ammunition Plant Hand Held Signal Flight Assembly, Rocket Barrel Assembly, 40 MM Signal, Final Packaging/Pack-Out, and Star Finishing

    Science.gov (United States)

    1990-03-01

    wood protectors in the HHS Rocket Barrel Assembly Operations. d) Use of hot melt sealant rather than lacquer on the end of the assembled Hand Held...4OL.UA8LYADHRlE CG411!cLVPAM-1 ~LW7m~I~o~c~c LCA ~TM18UX"Y.31nSRGU-11 STiIM ASSELYJMACE FINh1TZ1A1*4CWAJKRZAM’ WAOiNt rs~my" LOCATM1ED 0~7 LOCA1ED’ IWCM-1W...Moorfeed Fairview, PA Indianapolis, IN Voice Synthesis Module Square D Micro Chip Technology Palatine, IL Chandler, AZ 85224 Vacuum Unit Venturi’s

  4. Extra-oral dental radiography for disaster victims using a flat panel X-ray detector and a hand-held X-ray generator.

    Science.gov (United States)

    Ohtani, M; Oshima, T; Mimasaka, S

    2017-12-01

    Forensic odontologists commonly incise the skin for post-mortem dental examinations when it is difficult to open the victim's mouth. However, it is prohibited by law to incise dead bodies without permission in Japan. Therefore, we attempted using extra-oral dental radiography, using a digital X-ray equipment with rechargeable batteries, to overcome this restriction. A phantom was placed in the prone position on a table, and three plain dental radiographs were used per case: "lateral oblique radiographs" for left and right posterior teeth and a "contact radiograph" for anterior teeth were taken using a flat panel X-ray detector and a hand-held X-ray generator. The resolving power of the images was measured by a resolution test chart, and the scattered X-ray dose was measured using an ionization chamber-type survey meter. The resolving power of the flat panel X-ray detector was 3.0 lp/mm, which was less than that of intra-oral dental methods, but the three extra-oral plain dental radiographs provided the overall dental information from outside of the mouth, and this approach was less time-consuming. In addition, the higher dose of scattered X-rays was laterally distributed, but the dose per case was much less than that of intra-oral dental radiographs. Extra-oral plain dental radiography can be used for disaster victim identification by dental methods even when it is difficult to open the mouth. Portable and rechargeable devices, such as a flat panel X-ray detector and a hand-held X-ray generator, are convenient to bring and use anywhere, even at a disaster scene lacking electricity and water.

  5. Use of a hand-held bladder ultrasound scanner in the assessment of dehydration and monitoring response to treatment in a paediatric emergency department.

    Science.gov (United States)

    Enright, Kevin; Beattie, Tom; Taheri, Sepideh

    2010-10-01

    Dehydration is a common concern in paediatric emergency care. Limited tools are available to assess reduced urine production, which is commonly cited as a reliable marker of dehydration. To evaluate the utility of a hand-held bladder ultrasound scanner in monitoring urine production in children attending the emergency department with suspected dehydration. A prospective pilot study was undertaken on a convenience sample of patients presenting with suspected dehydration. Serial bladder ultrasound scanning was performed to monitor urine output. Dehydration was assessed clinically using the WHO guide to dehydration assessment. Decisions about treatment and admission were made independently of the urine output measurements obtained using the bladder scanner. 45 children were studied. Using the WHO guide, 33 (73%) had mild dehydration, 8 (18%) had moderate dehydration and 4 (9%) had severe dehydration. There was a significant difference in estimated urine production between those admitted and those discharged (0.9±1.2 ml/kg/h vs 1.8±1.5 ml/kg/h, p=0.01) and between those with mild dehydration versus moderate/severe dehydration (2.3±1.5 ml/kg/h vs 0.6±0.7 ml/kg/h, p=0.0011). Urine output had been significantly reduced in those who had received an intravenous fluid bolus compared with those who had not (0.4±0.46 ml/kg/h vs 1.9±1.6 ml/kg/h, p=0.001). The hand-held bladder scanner is a convenient, non-invasive and objective adjunct in the assessment and management of children attending the emergency department with suspected dehydration.

  6. SARAS 2: a spectral radiometer for probing cosmic dawn and the epoch of reionization through detection of the global 21-cm signal

    Science.gov (United States)

    Singh, Saurabh; Subrahmanyan, Ravi; Shankar, N. Udaya; Rao, Mayuri Sathyanarayana; Girish, B. S.; Raghunathan, A.; Somashekar, R.; Srivani, K. S.

    2018-04-01

    The global 21-cm signal from Cosmic Dawn (CD) and the Epoch of Reionization (EoR), at redshifts z ˜ 6-30, probes the nature of first sources of radiation as well as physics of the Inter-Galactic Medium (IGM). Given that the signal is predicted to be extremely weak, of wide fractional bandwidth, and lies in a frequency range that is dominated by Galactic and Extragalactic foregrounds as well as Radio Frequency Interference, detection of the signal is a daunting task. Critical to the experiment is the manner in which the sky signal is represented through the instrument. It is of utmost importance to design a system whose spectral bandpass and additive spurious signals can be well calibrated and any calibration residual does not mimic the signal. Shaped Antenna measurement of the background RAdio Spectrum (SARAS) is an ongoing experiment that aims to detect the global 21-cm signal. Here we present the design philosophy of the SARAS 2 system and discuss its performance and limitations based on laboratory and field measurements. Laboratory tests with the antenna replaced with a variety of terminations, including a network model for the antenna impedance, show that the gain calibration and modeling of internal additive signals leave no residuals with Fourier amplitudes exceeding 2 mK, or residual Gaussians of 25 MHz width with amplitudes exceeding 2 mK. Thus, even accounting for reflection and radiation efficiency losses in the antenna, the SARAS 2 system is capable of detection of complex 21-cm profiles at the level predicted by currently favoured models for thermal baryon evolution.

  7. Hand-held indirect calorimeter offers advantages compared with prediction equations, in a group of overweight women, to determine resting energy expenditures and estimated total energy expenditures during research screening.

    Science.gov (United States)

    Spears, Karen E; Kim, Hyunsook; Behall, Kay M; Conway, Joan M

    2009-05-01

    To compare standardized prediction equations to a hand-held indirect calorimeter in estimating resting energy and total energy requirements in overweight women. Resting energy expenditure (REE) was measured by hand-held indirect calorimeter and calculated by prediction equations Harris-Benedict, Mifflin-St Jeor, World Health Organization/Food and Agriculture Organization/United Nations University (WHO), and Dietary Reference Intakes (DRI). Physical activity level, assessed by questionnaire, was used to estimate total energy expenditure (TEE). Subjects (n=39) were female nonsmokers older than 25 years of age with body mass index more than 25. Repeated measures analysis of variance, Bland-Altman plot, and fitted regression line of difference. A difference within +/-10% of two methods indicated agreement. Significant proportional bias was present between hand-held indirect calorimeter and prediction equations for REE and TEE (Pvalues and underestimated at higher values. Mean differences (+/-standard error) for REE and TEE between hand-held indirect calorimeter and Harris-Benedict were -5.98+/-46.7 kcal/day (P=0.90) and 21.40+/-75.7 kcal/day (P=0.78); between hand-held indirect calorimeter and Mifflin-St Jeor were 69.93+/-46.7 kcal/day (P=0.14) and 116.44+/-75.9 kcal/day (P=0.13); between hand-held indirect calorimeter and WHO were -22.03+/-48.4 kcal/day (P=0.65) and -15.8+/-77.9 kcal/day (P=0.84); and between hand-held indirect calorimeter and DRI were 39.65+/-47.4 kcal/day (P=0.41) and 56.36+/-85.5 kcal/day (P=0.51). Less than 50% of predictive equation values were within +/-10% of hand-held indirect calorimeter values, indicating poor agreement. A significant discrepancy between predicted and measured energy expenditure was observed. Further evaluation of hand-held indirect calorimeter research screening is needed.

  8. Glucose concentration in capillary blood of dairy cows obtained by a minimally invasive lancet technique and determined with three different hand-held devices.

    Science.gov (United States)

    Mair, B; Drillich, M; Klein-Jöbstl, D; Kanz, P; Borchardt, S; Meyer, L; Schwendenwein, I; Iwersen, M

    2016-02-24

    Dairy cows have a massive demand for glucose at the onset of lactation. A poor adaption to this period leads to an excessive negative energy balance with an increased risk for ketosis and impaired animal health and production. Besides the measurement of ketones, analysing the glucose concentration in blood is reported as helpful instrument for diagnosis and differentiation of ketosis. Monitoring metabolic parameters requires multiple blood sampling. In other species, new blood sampling techniques have been introduced in which small amounts of blood are rapidly analysed using electronic hand-held devices. The objective of this study was to evaluate the suitability of capillary blood for blood glucose measurement in dairy cows using the hand-held devices FreeStyle Precision (FSP, Abbott), GlucoMen LX Plus (GLX, A. Menarini) and the WellionVet GLUCO CALEA, (WGC, MED TRUST). In total, 240 capillary blood samples were obtained from dry and fresh lactating Holstein-Friesian cows. Blood was collected from the skin of the exterior vulva by using a lancet. For method comparison, additional blood samples were taken from a coccygeal vessel and analyzed in a laboratory. Glucose concentrations measured by a standard laboratory method were defined as the criterion standard. The Pearson correlation coefficients between the glucose concentrations analyzed in capillary blood with the devices and the reference were 73% for the FSP, 81% for the GLX and 41% for the WGC. Bland-Altman plots showed biases of -18.8 mg/dL for the FSP, -11.2 mg/dL for the GLX and +20.82 mg/dL for the WGC. The optimized threshold determined by a Receiver Operating Characteristics analysis to detect hyperglycemia using the FSP was 43 mg/dL with a sensitivity (Se) and specificity (Sp) of 76 and 80%. Using the GLX and WGC optimized thresholds were 49 mg/dL (Se = 92%, Sp = 85%) and 95 mg/dL (Se = 39%, Sp = 92%). The results of this study demonstrate good performance characteristics for the GLX

  9. Monitored background radiometer

    International Nuclear Information System (INIS)

    Ruel, C.

    1988-01-01

    A monitored background radiometer is described comprising: a thermally conductive housing; low conductivity support means mounted on the housing; a sensing plate mounted on the low conductivity support means and spaced from the housing so as to be thermally insulated from the housing and having an outwardly facing first surface; the sensing plate being disposed relative to the housing to receive direct electromagnetic radiation from sources exterior to the radiometer upon the first surface only; means for controllably heating the sensing plate; first temperature sensitive means to measure the temperature of the housing; and second temperature sensitive means to measure the temperature of the sensing plate, so that the heat flux at the sensing plate may be determined from the temperatures of the housing and sensing plate after calibration of the radiometer by measuring the temperatures of the housing and sensing plate while controllably heating the sensing plate

  10. The use of hand-held 35 mm color infrared imagery for estimates of suspended solids - A progress report. [in water pollution monitoring

    Science.gov (United States)

    Miller, W. F.; Whisler, F. D.; Robinette, H. R.; Finnie, D.; Cannon, T.

    1975-01-01

    A cost-effective aerial surveillance technique is proposed for detection and identification of suspended solids which would be operational for both governmental monitoring organizations and private individuals operating catfish farms. Sixteen catfish ponds were flown daily for seven days using two hand-held 35 mm cameras with both Kodachrome X and Ektachrome infrared film. Hue, value, and chroma designations were recorded for each pond on each date by three interpreters, and the accepted color was that recorded by at least two of the interpreters, or if there was a three hue range, the median was accepted. Relations between suspended solids and color designations were analyzed graphically, and chroma was discarded due to an apparent lack of correlation. The data obtained were then analyzed by multiple regression. Significant correlations were revealed between hue and value and total and inorganic suspended solids. If perfected, this technique could be developed to sufficent accuracy for large-scale reconnaissance surveys to monitor the quality of rivers and streams.

  11. Predicting meat quality traits of ovine m. semimembranosus, both fresh and following freezing and thawing, using a hand held Raman spectroscopic device.

    Science.gov (United States)

    Fowler, Stephanie M; Schmidt, Heinar; van de Ven, Remy; Wynn, Peter; Hopkins, David L

    2015-10-01

    Complementary studies were conducted to determine the potential for a Raman spectroscopic hand held device to predict meat quality traits of fresh lamb m. semimembranosus (topside) after ageing and freezing/thawing. Spectra were collected from 80 fresh muscles at 24h and 5d PM, another 80 muscles were measured at 24h, 5d and following freezing/thawing. Shear force, cooking loss, sarcomere length, colour, particle size, collagen content, pH24, pHu, purge and thaw loss were also measured. Results indicated a potential to predict pHu (R(2)cv=0.59), pH24 (R(2)cv=0.48) and purge (R(2)cv=0.42) using spectra collected 24h PM. L* could be predicted using spectra collected 24h (R(2)cv=0.33) or 5d PM (R(2)cv=0.33). This suggests that Raman spectroscopy is suited to identifying carcases which deviate from the normal metabolic processes and related meat quality traits. Copyright © 2015. Published by Elsevier Ltd.

  12. Hand-held optical sensor using denatured antibody coated electro-active polymer for ultra-trace detection of copper in blood serum and environmental samples.

    Science.gov (United States)

    Chandra, Sutapa; Dhawangale, Arvind; Mukherji, Soumyo

    2018-07-01

    An optimum copper concentration in environment is highly desired for all forms of life. We have developed an ultrasensitive copper sensor which functions from femto to micro molar concentration accurately (R 2 = 0.98). The sensor is based on denatured antibody immunoglobulin G (IgG), immobilized on polyaniline (PAni) which in turn is the coating on the core of an optical fiber. The sensing relies on changes in evanescent wave absorbance in the presence of the analyte. The sensor showed excellent selectivity towards Cu (II) ions over all other metal ions. The sensor was tested with lake and marine water samples to determine unknown concentrations of copper ions and the recovery results were within 90-115%, indicating reasonable accuracy. We further integrated the fiber-optic sensor with a miniaturized hand-held instrumentation platform to develop an accurate and field deployable device which can broadly be applicable to determine Cu (II) concentration in a wide range of systems - natural water bodies, soil as well as blood serum. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. What is the most cost-effective strategy to screen for left ventricular systolic dysfunction: natriuretic peptides, the electrocardiogram, hand-held echocardiography, traditional echocardiography, or their combination?

    Science.gov (United States)

    Galasko, Gavin I W; Barnes, Sophie C; Collinson, Paul; Lahiri, Avijit; Senior, Roxy

    2006-01-01

    To assess the screening characteristics and cost-effectiveness of screening for left ventricular systolic dysfunction (LVSD) in community subjects. A total of 1392 members of the general public and 928 higher risk subjects were randomly selected from seven community practices. Attending subjects underwent an ECG, N-terminal pro-brain natriuretic peptide (NTproBNP) serum levels, and traditional echocardiography (TE). A total of 533 consecutive subjects underwent hand-held echocardiography (HE). The screening characteristics and cost-effectiveness (cost per case of LVSD diagnosed) of eight strategies to predict LVSD (LVSD cost-effective, screening low-risk subjects least cost-effective. TE screening was the least cost-effective strategy. NTproBNP screening gave similar cost savings to ECG screening; HE screening greater cost-savings, and HE screening following NTproBNP or ECG pre-screening the greatest cost-savings, costing approximately 650 Euros per case of LVSD diagnosed in high-risk subjects (63% cost-savings vs.TE). Thus several different modalities allow cost-effective community-based screening for LVSD, especially in high-risk subjects. Such programmes would be cost-effective and miss few cases of LVSD in the community.

  14. Performance of hand-held whole-breast ultrasound based on BI-RADS in women with mammographically negative dense breast

    International Nuclear Information System (INIS)

    Youk, Ji Hyun; Kim, Eun-Kyung; Kim, Min Jung; Kwak, Jin Young; Son, Eun Ju

    2011-01-01

    To assess the performance of breast ultrasound based on BI-RADS final assessment categories in women with mammographically negative dense breast. Of 3,820 cases with mammographically negative dense breast and subsequent hand-held bilateral whole-breast ultrasound, a total of 1,507 cases in 1,046 women who had biopsy or at least 2-year follow-up ultrasound constituted the basis of this retrospective study. Cancer rate of each sonographic BI-RADS category was determined and medical audit was performed separately in screening-general, screening-treated, and diagnostic group. A total of 43 cases (2.9%) were confirmed as malignancy. Cancer rate among BI-RADS categories was significantly different (p < 0.0001). Among three groups, the cancer rate was significantly different (p < 0.0001) and the highest in diagnostic group (15.8%, 22 of 139). Abnormal interpretation rate, PPV of biopsy performed, cancer detection rate, and rate of early stage cancer, and the size of invasive cancer were significantly different among three groups and the highest in diagnostic group. Regarding cancer characteristics, the proportion of advanced cancer was the highest in diagnostic group. Breast ultrasound based on BI-RADS as an adjunctive to negative mammography can be useful for predicting malignancy in women with dense breast. (orig.)

  15. Evaluation of an automated breast 3D-ultrasound system by comparing it with hand-held ultrasound (HHUS) and mammography.

    Science.gov (United States)

    Golatta, Michael; Baggs, Christina; Schweitzer-Martin, Mirjam; Domschke, Christoph; Schott, Sarah; Harcos, Aba; Scharf, Alexander; Junkermann, Hans; Rauch, Geraldine; Rom, Joachim; Sohn, Christof; Heil, Joerg

    2015-04-01

    Automated three-dimensional (3D) breast ultrasound (US) systems are meant to overcome the shortcomings of hand-held ultrasound (HHUS). The aim of this study is to analyze and compare clinical performance of an automated 3D-US system by comparing it with HHUS, mammography and the clinical gold standard (defined as the combination of HHUS, mammography and-if indicated-histology). Nine hundred and eighty three patients (=1,966 breasts) were enrolled in this monocentric, explorative and prospective cohort study. All examinations were analyzed blinded to the patients´ history and to the results of the routine imaging. The agreement of automated 3D-US with HHUS, mammography and the gold standard was assessed with kappa statistics. Sensitivity, specificity and positive and negative predictive value were calculated to assess the test performance. Blinded to the results of the gold standard the agreement between automated 3D-US and HHUS or mammography was fair, given by a Kappa coefficient of 0.31 (95% CI [0.26;0.36], p automated 3D-US the sensitivity improved to 84% (NPV = 99%, specificity = 85%). The results of this study let us suggest, that automated 3D-US might be a helpful new tool in breast imaging, especially in screening.

  16. Reliability of hand-held dynamometry for measurement of lower limb muscle strength in children with Duchenne and Becker muscular dystrophy

    Directory of Open Access Journals (Sweden)

    Wei SHI

    2015-05-01

    Full Text Available Objective To determine the reliability of hand-held dynamometry (HHD for lower limb isometric muscle strength measurement in children with Duchenne and Becker muscular dystrophy (DMD/BMD.  Methods A total of 21 children [20 males and one female; mean age was (7.88 ± 2.87 years, ranging between 3.96-14.09 years; mean age at diagnosis was (5.88 ± 2.88 years, ranging between 1.35-12.89 years; mean height was (120.64 ± 16.30 cm, ranging between 97-153 cm; mean body weight was (24.62 ± 9.05 kg, ranging between 14-50 kg] with DMD (19/21 and BMD (2/21 were involved from Rehabilitation Center of Children's Hospital of Fudan University. The muscle strength of hip, knee and ankle was measured by HHD under standardized test methods. The test-retest results were compared to determine the inter-test reliability, and the results among testers were compared to determine the inter-tester reliability.  Results HHD showed fine inter-tester reliability (ICC = 0.762-0.978 and inter-test reliability (ICC = 0.690-0.938 in measuring lower limb muscle strength of children with DMD/BMD. Results also showed relatively poor reliability in distal muscle groups (foot plantar flexion and dorsiflexion.  Conclusions HHD, showing fine inter-tester and inter-test reliability in measuring the lower limb muscle strength of children with DMD/BMD, can be used in monitoring muscle strength changing and assessing effects of clinical interventions. DOI: 10.3969/j.issn.1672-6731.2015.05.009

  17. An Approach to Precise Nitrogen Management Using Hand-Held Crop Sensor Measurements and Winter Wheat Yield Mapping in a Mediterranean Environment

    Directory of Open Access Journals (Sweden)

    Lucía Quebrajo

    2015-03-01

    Full Text Available Regardless of the crop production system, nutrients inputs must be controlled at or below a certain economic threshold to achieve an acceptable level of profitability. The use of management zones and variable-rate fertilizer applications is gaining popularity in precision agriculture. Many researchers have evaluated the application of final yield maps and geo-referenced geophysical measurements (e.g., apparent soil electrical conductivity-ECa as a method of establishing relatively homogeneous management zones within the same plot. Yield estimation models based on crop conditions at certain growth stages, soil nutrient statuses, agronomic factors, moisture statuses, and weed/pest pressures are a primary goal in precision agriculture. This study attempted to achieve the following objectives: (1 to investigate the potential for predicting winter wheat yields using vegetation measurements (the Normalized Difference Vegetation Index—NDVI at the beginning of the season, thereby allowing for a yield response to nitrogen (N fertilizer; and (2 evaluate the feasibility of using inexpensive optical sensor measurements in a Mediterranean environment. A field experiment was conducted in two commercial wheat fields near Seville, in southwestern Spain. Yield data were collected at harvest using a yield monitoring system (RDS Ceres II-volumetric meter installed on a combine. Wheat yield and NDVI values of 3498 ± 481 kg ha−1 and 0.67 ± 0.04 nm nm−1 (field 1 and 3221 ± 531 kg ha−1 and 0.68 ± 0.05 nm nm−1 (field 2 were obtained. In both fields, the yield and NDVI exhibited a strong Pearson correlation, with rxy = 0.64 and p < 10−4 in field 1 and rxy = 0.78 and p < 10−4 in field 2. The preliminary results indicate that hand-held crop sensor-based N management can be applied to wheat production in Spain and has the potential to increase agronomic N-use efficiency on a long-term basis.

  18. Assessment of Laparoscopic Skills Performance: 2D Versus 3D Vision and Classic Instrument Versus New Hand-Held Robotic Device for Laparoscopy.

    Science.gov (United States)

    Leite, Mariana; Carvalho, Ana F; Costa, Patrício; Pereira, Ricardo; Moreira, Antonio; Rodrigues, Nuno; Laureano, Sara; Correia-Pinto, Jorge; Vilaça, João L; Leão, Pedro

    2016-02-01

    Laparoscopic surgery has undeniable advantages, such as reduced postoperative pain, smaller incisions, and faster recovery. However, to improve surgeons' performance, ergonomic adaptations of the laparoscopic instruments and introduction of robotic technology are needed. The aim of this study was to ascertain the influence of a new hand-held robotic device for laparoscopy (HHRDL) and 3D vision on laparoscopic skills performance of 2 different groups, naïve and expert. Each participant performed 3 laparoscopic tasks-Peg transfer, Wire chaser, Knot-in 4 different ways. With random sequencing we assigned the execution order of the tasks based on the first type of visualization and laparoscopic instrument. Time to complete each laparoscopic task was recorded and analyzed with one-way analysis of variance. Eleven experts and 15 naïve participants were included. Three-dimensional video helps the naïve group to get better performance in Peg transfer, Wire chaser 2 hands, and Knot; the new device improved the execution of all laparoscopic tasks (P < .05). For expert group, the 3D video system benefited them in Peg transfer and Wire chaser 1 hand, and the robotic device in Peg transfer, Wire chaser 1 hand, and Wire chaser 2 hands (P < .05). The HHRDL helps the execution of difficult laparoscopic tasks, such as Knot, in the naïve group. Three-dimensional vision makes the laparoscopic performance of the participants without laparoscopic experience easier, unlike those with experience in laparoscopic procedures. © The Author(s) 2015.

  19. A feasibility and efficacy trial of a hand-held humidification device in patients undergoing radiotherapy for head and neck cancer.

    Science.gov (United States)

    Ghosh, Priyanka; Lazar, Ann A; Ryan, William R; Yom, Sue S

    2017-08-01

    This study aimed to evaluate the effects of warm-mist humidification during and after head and neck radiation therapy (HN RT) on quality of life (QOL), as measured by the M. D. Anderson Symptom Inventory-Head and Neck (MDASI-HN) HN score. A secondary aim was to compare QOL among compliers (≥60% of protocol-recommended usage) versus non-compliers. Twenty patients self-administered a hand-held, self-sterilizing humidification device for a recommended time of at least 15 min twice daily for 12 weeks. Patients completed the MDASI-HN instrument at RT start, after 6 weeks, and after 12 weeks. Compliance was reported weekly. The average HN score at baseline was 1.7 (SD = 1.8) and increased to 6.0 (SD = 1.6) after 6 weeks; this increase was much higher than anticipated and the primary endpoint could not be reached. However, compliers had an average of nearly two less HN symptoms (-1.8, 95% CI -4 to 0.2; p = 0.08) than non-compliers at 6 weeks and fewer symptoms at 12 weeks as well (-0.9, 95% CI -2.9 to 1.2; p = 0.39). The most common terms patients used to describe humidification were "helpful" and "soothing." Compliance with humidification during RT was associated with fewer reported HN symptoms and a strong trend to better QOL. Improvements were seen from compliance with occasional required use of a portable, inexpensive device. Our findings support continued efforts to reduce barriers to humidification, as an intervention that should be considered for standard HN RT clinical practice.

  20. Breast-density assessment with hand-held ultrasound: A novel biomarker to assess breast cancer risk and to tailor screening?

    Science.gov (United States)

    Sanabria, Sergio J; Goksel, Orcun; Martini, Katharina; Forte, Serafino; Frauenfelder, Thomas; Kubik-Huch, Rahel A; Rominger, Marga B

    2018-03-19

    To assess feasibility and diagnostic accuracy of a novel hand-held ultrasound (US) method for breast density assessment that measures the speed of sound (SoS), in comparison to the ACR mammographic (MG) categories. ACR-MG density (a=fatty to d=extremely dense) and SoS-US were assessed in the retromamillary, inner and outer segments of 106 women by two radiographers. A conventional US system was used for SoS-US. A reflector served as timing reference for US signals transmitted through the breasts. Four blinded readers assessed average SoS (m/s), ΔSoS (segment-variation SoS; m/s) and the ACR-MG density. The highest SoS and ΔSoS values of the three segments were used for MG-ACR whole breast comparison. SoS-US breasts were examined in densities a-d were 1,421 m/s (SD 14), 1,432 m/s (SD 17), 1,448 m/s (SD 20) and 1,500 m/s (SD 31), with significant differences between all groups (pdensity was evident (r s =0.622, p=density without discomfort, readers evaluated measurements with high inter-reader agreement, and SoS-US correlated significantly with ACR-MG breast-density categories. • The novel speed-of-sound ultrasound correlated significantly with mammographic ACR breast density categories. • Radiographers measured breast density without women discomfort or radiation. • SoS-US can be implemented on a standard US machine. • SoS-US shows potential for a quantifiable, cost-effective assessment of breast density.

  1. A feasibility study to develop a diabetes prevention program for young adults with prediabetes using digital platforms and a hand held device

    Science.gov (United States)

    Cha, EunSeok; Kim, Kevin H.; Umpierrez, Guillermo; Dawkins, Colleen R.; Bello, Morenike K.; Lerner, Hannah; Narayan, K.M. Venkat; Dunbar, Sandra B.

    2014-01-01

    Purpose The purpose of the pilot study was to examine the feasibility and preliminary efficacy of an age-specific diabetes prevention program in young adults with prediabetes. Methods One group pretest-posttest design was conducted. The inclusion criteria were young adults age 18–29 years with prediabetes [either Impaird fasting glucose [IFG] (100–125 mg/dL), or an A1C of 5.7%–6.4%]. Fifteen participants were enrolled in this study. A technology based lifestyle coaching program focused on diet and physical activity and incorporating a hand-held device and digital platforms was developed and tested. Psychosocial factors (health literacy, illness perception, self-efficacy, therapeutic efficacy) based on social cognitive theory, changes in diet and physical activity, and cardiometabolic risk factors were assessed at baseline and week 12 after intervention. A paired-samples t-test was performed to examine changes between baseline and post-intervention on each psychosocial and physical variable. Results Participants (n= 13 completers) were mean age 24.4 yrs [SD: 2.2], 23.1% male, and 53.8% were African American. Overall, the participants were satisfied with the intervention (M = 4.15 on a 5-point Likert scale). Between pre and post testing, BMI and A1C decreased from 41.0 ±7.3 to 40.1±7.0 and 6.0% ± .5 to 5.6% ± .5, respectively, while fasting glucose did not significantly change (92.6±11 mg/dl to 97.6 ±14.3 mg/dl). Conclusion The intervention resulted in reduced A1C and a trend for decreased BMI in obese sedentary young adults with prediabetes after 12 weeks of intervention. Further study through a randomized clinical trial with a longer intervention period is warranted. PMID:24950683

  2. BETA digital beta radiometer

    International Nuclear Information System (INIS)

    Borovikov, N.V.; Kosinov, G.A.; Fedorov, Yu.N.

    1989-01-01

    Portable transportable digital beta radiometer providing for measuring beta-decay radionuclide specific activity in the range from 5x10 -9 up to 10 -6 Cu/kg (Cu/l) with error of ±25% is designed and introduced into commercial production for determination of volume and specific water and food radioactivity. The device specifications are given. Experience in the BETA radiometer application under conditions of the Chernobyl' NPP 30-km zone has shown that it is convenient for measuring specific activity of the order of 10 -8 Cu/kg, and application of a set of different beta detectors gives an opportunity to use it for surface contamination measurement in wide range of the measured value

  3. Millimeter radiometer system technology

    Science.gov (United States)

    Wilson, W. J.; Swanson, P. N.

    1989-07-01

    JPL has had a large amount of experience with spaceborne microwave/millimeter wave radiometers for remote sensing. All of the instruments use filled aperture antenna systems from 5 cm diameter for the microwave Sounder Units (MSU), 16 m for the microwave limb sounder (MLS) to 20 m for the large deployable reflector (LDR). The advantages of filled aperture antenna systems are presented. The requirements of the 10 m Geoplat antenna system, 10 m multified antenna, and the MLS are briefly discussed.

  4. Hurricane Imaging Radiometer

    Science.gov (United States)

    Cecil, Daniel J.; Biswas, Sayak K.; James, Mark W.; Roberts, J. Brent; Jones, W. Linwood; Johnson, James; Farrar, Spencer; Sahawneh, Saleem; Ruf, Christopher S.; Morris, Mary; hide

    2014-01-01

    The Hurricane Imaging Radiometer (HIRAD) is a synthetic thinned array passive microwave radiometer designed to allow retrieval of surface wind speed in hurricanes, up through category five intensity. The retrieval technology follows the Stepped Frequency Microwave Radiometer (SFMR), which measures surface wind speed in hurricanes along a narrow strip beneath the aircraft. HIRAD maps wind speeds in a swath below the aircraft, about 50-60 km wide when flown in the lower stratosphere. HIRAD has flown in the NASA Genesis and Rapid Intensification Processes (GRIP) experiment in 2010 on a WB-57 aircraft, and on a Global Hawk unmanned aircraft system (UAS) in 2012 and 2013 as part of NASA's Hurricane and Severe Storms Sentinel (HS3) program. The GRIP program included flights over Hurricanes Earl and Karl (2010). The 2012 HS3 deployment did not include any hurricane flights for the UAS carrying HIRAD. The 2013 HS3 flights included one flight over the predecessor to TS Gabrielle, and one flight over Hurricane Ingrid. This presentation will describe the HIRAD instrument, its results from the 2010 and 2013 flights, and potential future developments.

  5. Evaluation of a hand-held far-ultraviolet radiation device for decontamination of Clostridium difficile and other healthcare-associated pathogens

    Directory of Open Access Journals (Sweden)

    Nerandzic Michelle M

    2012-05-01

    Full Text Available Abstract Background Environmental surfaces play an important role in transmission of healthcare-associated pathogens. There is a need for new disinfection methods that are effective against Clostridium difficile spores, but also safe and rapid. The Sterilray™ Disinfection Wand device is a hand-held room decontamination technology that utilizes far-ultraviolet radiation (185-230 nm to kill pathogens. Methods We examined the efficacy of disinfection using the Sterilray device in the laboratory, in rooms of hospitalized patients, and on surfaces outside of patient rooms (i.e. keyboards and portable medical equipment. Cultures for C. difficile, methicillin-resistant Staphylococcus aureus (MRSA, and vancomycin-resistant Enterococcus (VRE were collected from commonly-touched surfaces before and after use of the Sterilray device. Results On inoculated surfaces in the laboratory, application of the Sterilray device at a radiant dose of 100 mJ/cm2 for ~ 5 seconds consistently reduced recovery of C. difficile spores by 4.4 CFU log10, MRSA by 5.4 log10CFU and of VRE by 6.9 log10CFU. A >3 log10 reduction of MRSA and VRE was achieved in ~2 seconds at a lower radiant dose, but killing of C. difficile spores was significantly reduced. On keyboards and portable medical equipment that were inoculated with C. difficile spores, application of the Sterilray device at a radiant dose of 100���mJ/cm2 for ~ 5 seconds reduced contamination by 3.2 log10CFU. However, the presence of organic material reduced the lethal effect of the far-UV radiation. In hospital rooms that were not pre-cleaned, disinfection with the Sterilray device significantly reduced the frequency of positive C. difficile and MRSA cultures (P =0.007. Conclusions The Sterilray™ Disinfection Wand is a novel environmental disinfection technology that rapidly kills C. difficile spores and other healthcare-associated pathogens on surfaces. However, the presence of organic matter

  6. Manual muscle testing and hand-held dynamometry in people with inflammatory myopathy: An intra- and interrater reliability and validity study.

    Science.gov (United States)

    Baschung Pfister, Pierrette; de Bruin, Eling D; Sterkele, Iris; Maurer, Britta; de Bie, Rob A; Knols, Ruud H

    2018-01-01

    Manual muscle testing (MMT) and hand-held dynamometry (HHD) are commonly used in people with inflammatory myopathy (IM), but their clinimetric properties have not yet been sufficiently studied. To evaluate the reliability and validity of MMT and HHD, maximum isometric strength was measured in eight muscle groups across three measurement events. To evaluate reliability of HHD, intra-class correlation coefficients (ICC), the standard error of measurements (SEM) and smallest detectable changes (SDC) were calculated. To measure reliability of MMT linear Cohen`s Kappa was computed for single muscle groups and ICC for total score. Additionally, correlations between MMT8 and HHD were evaluated with Spearman Correlation Coefficients. Fifty people with myositis (56±14 years, 76% female) were included in the study. Intra-and interrater reliability of HHD yielded excellent ICCs (0.75-0.97) for all muscle groups, except for interrater reliability of ankle extension (0.61). The corresponding SEMs% ranged from 8 to 28% and the SDCs% from 23 to 65%. MMT8 total score revealed excellent intra-and interrater reliability (ICC>0.9). Intrarater reliability of single muscle groups was substantial for shoulder and hip abduction, elbow and neck flexion, and hip extension (0.64-0.69); moderate for wrist (0.53) and knee extension (0.49) and fair for ankle extension (0.35). Interrater reliability was moderate for neck flexion (0.54) and hip abduction (0.44); fair for shoulder abduction, elbow flexion, wrist and ankle extension (0.20-0.33); and slight for knee extension (0.08). Correlations between the two tests were low for wrist, knee, ankle, and hip extension; moderate for elbow flexion, neck flexion and hip abduction; and good for shoulder abduction. In conclusion, the MMT8 total score is a reliable assessment to consider general muscle weakness in people with myositis but not for single muscle groups. In contrast, our results confirm that HHD can be recommended to evaluate strength of

  7. Monitored background radiometer

    International Nuclear Information System (INIS)

    Ruel, C.

    1988-01-01

    This radiometer accurately measures IR and solar spectrum radiation in a vacuum, and accounts for radiation loss from its sensing plate by measuring the housing temperature. Calibration is performed by measuring the temperature of the sensing plate and housing while power to a heater attached to the sensing plate is varied. The square of the difference between the measured power dissipation of the heater and the heat absorbed by the sensing plate as determined from the heat balance equation of the sensing plate is minimized to obtain calibration factors for the heat balance equation

  8. A Multifrequency Radiometer System

    DEFF Research Database (Denmark)

    Skou, Niels

    1977-01-01

    A radiometer system having four channels: 5 GHz, l7 GHz, 34 GHz, all vertical polarization, and a 34 GHz sky horn, will be described. The system which is designed for collecting glaciological and oceanographic data is intended for airborne use and imaging is achieved by means of a multifrequency...... conically scanning antenna. Implementation of the noise-injection technique ensures the high absolute accuracy needed for oceanographic purposes. The collected data can be preprocessed in a microcomputer system and displayed in real time. Simultaneously, the data are recorded digitally on tape for more...

  9. Hand-held triangulation laser profilometer with audio output for blind people Profilométre laser à triangulation tenu en main avec sortie sonare pour non-voyants

    Science.gov (United States)

    Farcy, R.; Damaschini, R.

    1998-06-01

    We describe a device currently under industrial development which will give to the blind a means of three-dimensional space perception. It consists of a 350 g hand-held triangulating laser telemeter including electronic parts and batteries, with auditory feedback either inside the apparatus or close to the ear. The microprocessor unit converts in real time the distance measured by the telemeter into a musical note. Scanning the space with an adequate movement of the hand produces musical lines corresponding to the profiles of the environment. We discuss the optical configuration of the system relative to our first year of clinical experimentation.

  10. Evaluation of methods to determine the spectral variations of aerosol optical thickness

    Digital Repository Service at National Institute of Oceanography (India)

    Suresh, T.; Talaulikar, M.; Rodrigues, A.; Desa, E.; Chauhan, P.

    The methods used to derive spectral variations of aerosol optical thickness, AOT are evaluated. For our analysis we have used the AOT measured using a hand held sunphotometer at the coastal station on the west coast of India, Dona-Paula, Goa...

  11. Double-polarizating scanning radiometer

    International Nuclear Information System (INIS)

    Mishev, D.N.; Nazyrski, T.G.

    1986-01-01

    The double-polarizating single-channel scanning radiometer comprises the following serial connected parts: a scanning double-polarizating aerial, a block for polarization separation, a radiometer receiver, an analog-to-digit converter and an information flow forming block. The low frequency input of the radiometer receiver is connected with a control block, which is also connected with a first bus of a microprocessor, the second bus of which is connected with the A-D converter. The control input of the scanning double-polarizating aerial is connected with the first microprocessor bus. The control inputs of the block for polarization separation are linked by an electronic switch with the output of the forming block, the input of which is connected to the first input of the control block. The control inputs of the block for polarization separation are connected with the second and the third input of the information flow forming block. 2 cls

  12. Radiometer Testbed Development for SWOT

    Science.gov (United States)

    Kangaslahti, Pekka; Brown, Shannon; Gaier, Todd; Dawson, Douglas; Harding, Dennis; Fu, Lee-Lueng; Esteban-Fernandez, Daniel

    2010-01-01

    Conventional altimeters include nadir looking colocated 18-37 GHz microwave radiometer to measure wet tropospheric path delay. These have reduced accuracy in coastal zone (within 50 km from land) and do not provide wet path delay over land. The addition of high frequency channels to Jason-class radiometer will improve retrievals in coastal regions and enable retrievals over land. High-frequency window channels, 90, 130 and 166 GHz are optimum for improving performance in coastal region and channels on 183 GHz water vapor line are ideal for over-land retrievals.

  13. Microwave Radiometer Systems, Design and Analysis

    DEFF Research Database (Denmark)

    Skou, Niels; Vine, David Le

    Two important microwave remote sensors are the radar and the radiometer. There have been a number of books written on various aspects of radar, but there have been only a few written on microwave radiometers, especially on subjects of how to design and build radiometer systems. This book, which...

  14. Microwave Radiometer Linearity Measured by Simple Means

    DEFF Research Database (Denmark)

    Skou, Niels

    2002-01-01

    Modern spaceborne radiometer systems feature an almost perfect on-board calibration, hence the primary calibration task to be carried out before launch is a check of radiometer linearity. This paper describes two ways of measuring linearity of microwave radiometers only requiring relatively simple...

  15. Hand-held personnel and vehicle monitors

    International Nuclear Information System (INIS)

    Kunz, W.E.; Chambers, W.H.; Henry, C.N.; France, S.W.; Millegan, D.R.; Hastings, R.D.; Worth, G.M.

    1976-05-01

    A light, rugged monitor has been developed for special nuclear materials (SNM) searches at material-access and protection-area exits. This monitor accepts gamma-ray pulses from a NaI(Tl) detector, integrates for a preset counting interval (typically 0.3 s), and produces an audible alarm whenever the counts in the interval exceed the trip level that is a preset multiple of the stored background count. Because the monitor is silent except when the alarm is operating, personnel with little special training can conduct more effective searches in a noisy and distracting environment than they can with conventional audible monitoring of individual radiation counts. The monitor is also more sensitive than conventional monitors that provide audible indication of the count rate

  16. Hand-held ultrasound serving three EDs.

    Science.gov (United States)

    2007-02-01

    Having a portable ultrasound available to your ED will enable you to perform scans during the nighttime hours, instead of having patients wait for several hours until the radiology department opens. Additional time can be saved by having a technologist read the scans, which frees your ED physicians for other duties. Having ED docs contact the technologist directly, rather than going through a resident, also saves valuable time. Arriving at a diagnosis more quickly provides a boost to patient safety.

  17. Simple Multiplexing Hand-Held Control Unit

    Science.gov (United States)

    Hannaford, Blake

    1989-01-01

    Multiplexer consists of series of resistors, each shunted by single-pole, single-throw switch. User operates switches by pressing buttons or squeezing triggers. Prototype includes three switches operated successfully in over 200 hours of system operations. Number of switches accommodated determined by signal-to-noise ratio of current source, noise induced in control unit and cable, and number of bits in output of analog-to-digital converter. Because many computer-contolled robots have extra analog-to-digital channels, such multiplexer added at little extra cost.

  18. Calibration of IR test chambers with the missile defense transfer radiometer

    Science.gov (United States)

    Kaplan, Simon G.; Woods, Solomon I.; Carter, Adriaan C.; Jung, Timothy M.

    2013-05-01

    The Missile Defense Transfer Radiometer (MDXR) is designed to calibrate infrared collimated and flood sources over the fW/cm2 to W/cm2 power range from 3 μm to 28μ m in wavelength. The MDXR operates in three different modes: as a filter radiometer, a Fourier-transform spectrometer (FTS)-based spectroradiometer, and as an absolute cryogenic radiometer (ACR). Since 2010, the MDXR has made measurements of the collimated infrared irradiance at the output port of seven different infrared test chambers at several facilities. We present a selection of results from these calibration efforts compared to signal predictions from the respective chamber models for the three different MDXR calibration modes. We also compare the results to previous measurements made of the same chambers with a legacy transfer radiometer, the NIST BXR. In general, the results are found to agree within their combined uncertainties, with the MDXR having 30 % lower uncertainty and greater spectral coverage.

  19. Reliability of maximal isometric knee strength testing with modified hand-held dynamometry in patients awaiting total knee arthroplasty: useful in research and individual patient settings? A reliability study

    Directory of Open Access Journals (Sweden)

    Koblbauer Ian FH

    2011-10-01

    Full Text Available Abstract Background Patients undergoing total knee arthroplasty (TKA often experience strength deficits both pre- and post-operatively. As these deficits may have a direct impact on functional recovery, strength assessment should be performed in this patient population. For these assessments, reliable measurements should be used. This study aimed to determine the inter- and intrarater reliability of hand-held dynamometry (HHD in measuring isometric knee strength in patients awaiting TKA. Methods To determine interrater reliability, 32 patients (81.3% female were assessed by two examiners. Patients were assessed consecutively by both examiners on the same individual test dates. To determine intrarater reliability, a subgroup (n = 13 was again assessed by the examiners within four weeks of the initial testing procedure. Maximal isometric knee flexor and extensor strength were tested using a modified Citec hand-held dynamometer. Both the affected and unaffected knee were tested. Reliability was assessed using the Intraclass Correlation Coefficient (ICC. In addition, the Standard Error of Measurement (SEM and the Smallest Detectable Difference (SDD were used to determine reliability. Results In both the affected and unaffected knee, the inter- and intrarater reliability were good for knee flexors (ICC range 0.76-0.94 and excellent for knee extensors (ICC range 0.92-0.97. However, measurement error was high, displaying SDD ranges between 21.7% and 36.2% for interrater reliability and between 19.0% and 57.5% for intrarater reliability. Overall, measurement error was higher for the knee flexors than for the knee extensors. Conclusions Modified HHD appears to be a reliable strength measure, producing good to excellent ICC values for both inter- and intrarater reliability in a group of TKA patients. High SEM and SDD values, however, indicate high measurement error for individual measures. This study demonstrates that a modified HHD is appropriate to

  20. Intercomparison of characterization techniques of filter radiometers in the ultraviolet region

    International Nuclear Information System (INIS)

    Abu-Kassem, I.; Karha, P.; Harrison, N. J.; Nevas, S.; Hartree, W. S.

    2008-01-01

    Narrow-band filter radiometers at 248 nm, 313 nm, 330 nm and 368 nm wavelengths were used to compare calibration facilities of spectral (irradiance) responsivity at HUT, NPL and BNM-INM. The results are partly in agreement within the stated uncertainties. Use of demanding artefacts in the intercomparison revealed that the wavelength scales of the participating institutes deviate more than expected. Such effects cannot be seen in typical intercomparisons of spectral responsivity or spectral transmittance, where spectrally neutral samples are used.(author)

  1. A Scanning Microwave Radar and Radiometer

    DEFF Research Database (Denmark)

    Skou, Niels

    1995-01-01

    The Scanning Microwave Radar and Radiometer (SMRR) is a line scanner featuring a combined radar and radiometer system operating around 35 and 94 GHz. The layout of the SMRR is shown. The 2 offset antenna parabolas scan in synchronism, the receiver antenna has the highest gain in order to ensure...

  2. CAMEX-3 POLARIMETRIC SCANNING RADIOMETER (PSR) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Polarimetric Scanning Radiometer (PSR) is a versatile airborne microwave imaging radiometer developed by the Georgia Institute of Technology and the NOAA...

  3. Spectral Irradiance Measurements Based on Detector

    International Nuclear Information System (INIS)

    Lima, M S; Menegotto, T; Duarte, I; Da Silva, T Ferreira; Alves, L C; Alvarenga, A D; Almeida, G B; Couceiro, I B; Teixeira, R N

    2015-01-01

    This paper presents the preliminary results of the realization of absolute spectral irradiance scale at INMETRO in the ultraviolet, visible and infrared regions using filter radiometers as secondary standards. In the construction of these instruments are used, at least, apertures, interference filters and a trap detector. In the assembly of the trap detectors it was necessary to characterize several photocells in spatial uniformity and shunt resistance. All components were calibrated and these results were analyzed to mount the filter radiometer

  4. Microwave Radiometry and Radiometers for Ocean Applications

    DEFF Research Database (Denmark)

    Skou, Niels

    2008-01-01

    The microwave radiometer system measures, within its bandwidth, the naturally emitted radiation – the brightness temperature – of substances within its antenna’s field of view. Thus a radiometer is really a sensitive and calibrated microwave receiver. The radiometer can be a basic total power....../antenna size, and the problem: scanning antenna/space- craft stability. In many cases good compromises have been reached, as evident recalling the many successful missions throughout the recent 30 years. But in some cases the situation calls for special solutions, like the push-broom system or the synthetic...

  5. GRIP HURRICANE IMAGING RADIOMETER (HIRAD) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP Hurricane Imaging Radiometer (HIRAD) V1 dataset contains measurements of brightness temperature taken at 4, 5, 6 and 6.6 GHz, as well as MERRA 2 m wind...

  6. Microwave Radiometry and Radiometers for Ocean Applications

    DEFF Research Database (Denmark)

    Skou, Niels

    2008-01-01

    aperture radiometer technique, both yielding imaging capability without scanning. Typical applications of microwave radiometry concerning oceans are: sea salinity, sea surface temperature, wind speed and direction, sea ice detection and classification. However, in an attempt to measure properties...

  7. Modeling the frequency response of microwave radiometers with QUCS

    International Nuclear Information System (INIS)

    Zonca, A; Williams, B; Rubin, I; Meinhold, P; Lubin, P; Roucaries, B; D'Arcangelo, O; Franceschet, C; Mennella, A; Bersanelli, M; Jahn, S

    2010-01-01

    Characterization of the frequency response of coherent radiometric receivers is a key element in estimating the flux of astrophysical emissions, since the measured signal depends on the convolution of the source spectral emission with the instrument band shape. Laboratory Radio Frequency (RF) measurements of the instrument bandpass often require complex test setups and are subject to a number of systematic effects driven by thermal issues and impedance matching, particularly if cryogenic operation is involved. In this paper we present an approach to modeling radiometers bandpasses by integrating simulations and RF measurements of individual components. This method is based on QUCS (Quasi Universal Circuit Simulator), an open-source circuit simulator, which gives the flexibility of choosing among the available devices, implementing new analytical software models or using measured S-parameters. Therefore an independent estimate of the instrument bandpass is achieved using standard individual component measurements and validated analytical simulations. In order to automate the process of preparing input data, running simulations and exporting results we developed the Python package python-qucs and released it under GNU Public License. We discuss, as working cases, bandpass response modeling of the COFE and Planck Low Frequency Instrument (LFI) radiometers and compare results obtained with QUCS and with a commercial circuit simulator software. The main purpose of bandpass modeling in COFE is to optimize component matching, while in LFI they represent the best estimation of frequency response, since end-to-end measurements were strongly affected by systematic effects.

  8. Measurement of synchrotron radiation from the NBS SURF II using a silicon radiometer

    International Nuclear Information System (INIS)

    Schaefer, A.R.

    1980-01-01

    A project is described in which the synchrotron radiation output from the NBS storage ring known as SURF II, is measured using a well characterized silicon based radiometer. This device consists of a silicon photodiode coupled with two interference filters to restrict the spectral response to a finite and convenient spectral region for the measurement. Considerations required for the characterization of the radiometer will be discussed. The absolute radiant flux from the storage ring is also calculable from various machine parameters. A measurement of the number of circulating electrons will be derived from electron counting techniques at low levels. This will yield an important intercomparison between the synchrotron flux measurements determined in two entirely different ways. (orig.)

  9. Novel Cyclotron-Based Radiometal Production

    International Nuclear Information System (INIS)

    DeGrado, Timothy R.

    2013-01-01

    Accomplishments: (1) Construction of prototype solution target for radiometal production; (2) Testing of prototype target for production of following isotopes: a. Zr-89. Investigation of Zr-89 production from Y-89 nitrate solution. i. Defined problems of gas evolution and salt precipitation. ii. Solved problem of precipitation by addition of nitric acid. iii. Solved gas evolution problem with addition of backpressure regulator and constant degassing of target during irradiations. iv. Investigated effects of Y-89 nitrate concentration and beam current. v. Published abstracts at SNM and ISRS meetings; (3) Design of 2nd generation radiometal solution target. a. Included reflux chamber and smaller target volume to conserve precious target materials. b. Included aluminum for prototype and tantalum for working model. c. Included greater varicosities for improved heat transfer; and, (4) Construction of 2nd generation radiometal solution target started

  10. The Hurricane Imaging Radiometer: Present and Future

    Science.gov (United States)

    Miller, Timothy L.; James, M. W.; Roberts, J. B.; Biswas, S. K.; Cecil, D.; Jones, W. L.; Johnson, J.; Farrar, S.; Sahawneh, S.; Ruf, C. S.; hide

    2013-01-01

    The Hurricane Imaging Radiometer (HIRAD) is an airborne passive microwave radiometer designed to provide high resolution, wide swath imagery of surface wind speed in tropical cyclones from a low profile planar antenna with no mechanical scanning. Wind speed and rain rate images from HIRAD's first field campaign (GRIP, 2010) are presented here followed, by a discussion on the performance of the newly installed thermal control system during the 2012 HS3 campaign. The paper ends with a discussion on the next generation dual polarization HIRAD antenna (already designed) for a future system capable of measuring wind direction as well as wind speed.

  11. Dual color radiometer imagery and test results

    International Nuclear Information System (INIS)

    Silver, A.; Carlen, F.; Link, D.; Zegel, F.

    1989-01-01

    This paper presents a review of the technical characteristics of the Dual Color Radiometer and recent data and test results. The Dual Color Radiometer is a state-of-the-art device that provides simultaneous pixel to pixel registered thermal imagery in both the 3 to 5 and 8 to 12 micron regions. The device is unique in terms of its spatial and temperature resolution of less than 0.10 degrees C temperature and 0.10 milliradian spatial resolution. In addition, the device is tailored for use by the Automatic Target Recognizer (ATR) community

  12. Dynamic response of the thermometric net radiometer

    Science.gov (United States)

    J. D. Wilson; W. J. Massman; G. E. Swaters

    2009-01-01

    We computed the dynamic response of an idealized thermometric net radiometer, when driven by an oscillating net longwave radiation intended roughly to simulate rapid fluctuations of the radiative environment such as might be expected during field use of such devices. The study was motivated by curiosity as to whether non-linearity of the surface boundary conditions...

  13. Calibration of aerosol radiometers. Special aerosol sources

    International Nuclear Information System (INIS)

    Belkina, S.K.; Zalmanzon, Yu.E.; Kuznetsov, Yu.V.; Fertman, D.E.

    1988-01-01

    Problems of calibration of artificial aerosol radiometry and information-measurement systems of radiometer radiation control, in particular, are considered. Special aerosol source is suggested, which permits to perform certification and testing of aerosol channels of the systems in situ without the dismantling

  14. Balloon-borne radiometer profiler: Field observations

    International Nuclear Information System (INIS)

    Shaw, W.J.; Whiteman, C.D.; Anderson, G.A.; Alzheimer, J.M.; Hubbe, J.M.; Scott, K.A.

    1995-03-01

    This project involves the development of the capability of making routine soundings of broadband radiative fluxes and radiative flux divergences to heights of 1500m AGL. Described in this document are radiometers carried on a stabilized platform in a harness inserted in the tetherline of a tethered balloon meteriological sounding system. Field test results are given

  15. Dual Microwave Radiometer Experiment Field Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Marchand, Roger [Univ. of Washington, Seattle, WA (United States)

    2017-09-01

    Passive microwave radiometers (MWRs) are the most commonly used and accurate instruments the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Research Facility has to retrieve cloud liquid water path (LWP). The MWR measurements (microwave radiances or brightness temperatures) are often used to derive LWP using climatological constraints, but are frequently also combined with measurements from radar and other instruments for cloud microphysical retrievals. Nominally this latter approach improves the retrieval of LWP and other cloud microphysical quantities (such as effective radius or number concentration), but this also means that when MWR data are poor, other cloud microphysical quantities are also negatively affected. Unfortunately, current MWR data is often contaminated by water on the MWR radome. This water makes a substantial contribution to the measured radiance and typically results in retrievals of cloud liquid water and column water vapor that are biased high. While it is obvious when the contamination by standing water is large (and retrieval biases are large), much of the time it is difficult to know with confidence that there is no contamination. At present there is no attempt to estimate or correct for this source of error, and identification of problems is largely left to users. Typically users are advised to simply throw out all data when the MWR “wet-window” resistance-based sensor indicates water is present, but this sensor is adjusted by hand and is known to be temperamental. In order to address this problem, a pair of ARM microwave radiometers was deployed to the University of Washington (UW) in Seattle, Washington, USA. The radiometers were operated such that one radiometer was scanned under a cover that (nominally) prevents this radiometer radome from gathering water and permits measurements away from zenith; while the other radiometer is operated normally – open or uncovered - with the radome exposed to the sky

  16. A brief comparison of radiometers at NSIDC and their potential to generate long ESDRs

    Science.gov (United States)

    Moth, P.; Johnston, T.; Haran, T. M.; Fowler, D. K.

    2017-12-01

    Radiometers have played a big part in Earth observing science. In this poster we compare three such instruments: the Advanced Very-High-resolution Radiometer (AVHRR), the Moderate Resolution Imaging Spectroradiometer (MODIS), and the Visible Infrared Imaging Radiometer Suite (VIIRS). The NASA National Snow and Ice Distributed Active Archive Center (NSIDC DAAC) has archived cryospheric data from all three of these instruments. AVHRR was a 4-channel radiometer that was first launched in 1978 aboard the TIROS-N satellite. Subsequent missions launched improved versions of AVHRR with five and six channels, observing Earth in frequencies ranging from 0.58 μm to 12.5 μm with a resolution at nadir of 1.09 km. MODIS instruments fly onboard NASA's Earth Observing System (EOS) Terra and Aqua satellites. Launched in 1999 and 2002, respectively, they still produce much sought after data observed in 36 spectral bands ranging from 0.4 μm to 14.4 μm. Two bands image Earth at a nominal resolution of 250 m at nadir, five at 500 m, and the remaining 29 bands at 1 km. A ±55-degree scanning pattern at the sun-synchronous orbit of 705 km achieves a 2,330 km swath and provides global coverage every one to two days VIIRS, NOAA's latest radiometer, was launched aboard the Suomi National Polar-orbiting Partnership satellite on October 28, 2011. Working collaboratively, NASA and NOAA are producing data that is archived and distributed via NASA DAACs. The VIIRS radiometer comprises 22 bands; five for high-resolution imagery, 16 at moderate resolution, and one panchromatic day/night band. VIIRS is a whiskbroom scanning radiometer that covers the spectrum between 0.412 μm and 12.01 μm and acquires spatial resolutions at nadir of 750 m, 375 m, and 750 m, respectively. Although these instruments are configured with different spectral bands, each was designed with an eye to the future. MODIS can be thought of as a successor to the AVHRR mission, adding capabilities that yielded better data

  17. The JET ECE heterodyne radiometer and investigations of fast phenomena

    International Nuclear Information System (INIS)

    Bartlett, D.V.; Porte, L.

    1993-01-01

    In this paper, the design and performance characteristics of the JET heterodyne radiometer are reviewed, and some novel aspects of the instrument are described. Areas where the radiometer could benefit from further improvement are highlighted, and those improvements currently in progress are discussed. Some measurements which demonstrate the radiometer's power as a diagnostic of fast phenomena are presented. (orig.)

  18. Microfluidic radiolabeling of biomolecules with PET radiometals

    International Nuclear Information System (INIS)

    Zeng Dexing; Desai, Amit V.; Ranganathan, David; Wheeler, Tobias D.; Kenis, Paul J.A.; Reichert, David E.

    2013-01-01

    Introduction: A robust, versatile and compact microreactor has been designed, fabricated and tested for the labeling of bifunctional chelate conjugated biomolecules (BFC-BM) with PET radiometals. Methods: The developed microreactor was used to radiolabel a chelate, either 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) or 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) that had been conjugated to cyclo(Arg-Gly-Asp-DPhe-Lys) peptide, with both 64 Cu and 68 Ga respectively. The microreactor radiolabeling conditions were optimized by varying temperature, concentration and residence time. Results: Direct comparisons between the microreactor approach and conventional methods showed improved labeling yields and increased reproducibility with the microreactor under identical labeling conditions, due to enhanced mass and heat transfer at the microscale. More importantly, over 90% radiolabeling yields (incorporation of radiometal) were achieved with a 1:1 stoichiometry of bifunctional chelate biomolecule conjugate (BFC-BM) to radiometal in the microreactor, which potentially obviates extensive chromatographic purification that is typically required to remove the large excess of unlabeled biomolecule in radioligands prepared using conventional methods. Moreover, higher yields for radiolabeling of DOTA-functionalized BSA protein (Bovine Serum Albumin) were observed with 64 Cu/ 68 Ga using the microreactor, which demonstrates the ability to label both small and large molecules. Conclusions: A robust, reliable, compact microreactor capable of chelating radiometals with common chelates has been developed and validated. Based on our radiolabeling results, the reported microfluidic approach overall outperforms conventional radiosynthetic methods, and is a promising technology for the radiometal labeling of commonly utilized BFC-BM in aqueous solutions.

  19. Microfluidic radiolabeling of biomolecules with PET radiometals.

    Science.gov (United States)

    Zeng, Dexing; Desai, Amit V; Ranganathan, David; Wheeler, Tobias D; Kenis, Paul J A; Reichert, David E

    2013-01-01

    A robust, versatile and compact microreactor has been designed, fabricated and tested for the labeling of bifunctional chelate conjugated biomolecules (BFC-BM) with PET radiometals. The developed microreactor was used to radiolabel a chelate, either 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) or 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) that had been conjugated to cyclo(Arg-Gly-Asp-DPhe-Lys) peptide, with both ⁶⁴Cu and ⁶⁸Ga respectively. The microreactor radiolabeling conditions were optimized by varying temperature, concentration and residence time. Direct comparisons between the microreactor approach and conventional methods showed improved labeling yields and increased reproducibility with the microreactor under identical labeling conditions, due to enhanced mass and heat transfer at the microscale. More importantly, over 90% radiolabeling yields (incorporation of radiometal) were achieved with a 1:1 stoichiometry of bifunctional chelate biomolecule conjugate (BFC-BM) to radiometal in the microreactor, which potentially obviates extensive chromatographic purification that is typically required to remove the large excess of unlabeled biomolecule in radioligands prepared using conventional methods. Moreover, higher yields for radiolabeling of DOTA-functionalized BSA protein (Bovine Serum Albumin) were observed with ⁶⁴Cu/⁶⁸Ga using the microreactor, which demonstrates the ability to label both small and large molecules. A robust, reliable, compact microreactor capable of chelating radiometals with common chelates has been developed and validated. Based on our radiolabeling results, the reported microfluidic approach overall outperforms conventional radiosynthetic methods, and is a promising technology for the radiometal labeling of commonly utilized BFC-BM in aqueous solutions. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Cloud-based processing of multi-spectral imaging data

    Science.gov (United States)

    Bernat, Amir S.; Bolton, Frank J.; Weiser, Reuven; Levitz, David

    2017-03-01

    Multispectral imaging holds great promise as a non-contact tool for the assessment of tissue composition. Performing multi - spectral imaging on a hand held mobile device would allow to bring this technology and with it knowledge to low resource settings to provide a state of the art classification of tissue health. This modality however produces considerably larger data sets than white light imaging and requires preliminary image analysis for it to be used. The data then needs to be analyzed and logged, while not requiring too much of the system resource or a long computation time and battery use by the end point device. Cloud environments were designed to allow offloading of those problems by allowing end point devices (smartphones) to offload computationally hard tasks. For this end we present a method where the a hand held device based around a smartphone captures a multi - spectral dataset in a movie file format (mp4) and compare it to other image format in size, noise and correctness. We present the cloud configuration used for segmenting images to frames where they can later be used for further analysis.

  1. ATSR - The Along Track Scanning Radiometer For ERS-1

    Science.gov (United States)

    Llewellyn-Jones, David T.; Mutlow, C. T.

    1990-04-01

    The ATSR instrument is an advanced imaging radiometer designed to measure global sea surface temperature to an accuracy of the order of 0.3C from the ESA's ERS-1 satellite, due to be launched in late 1990. The instrument is designed to achieve a very precise correction for atmospheric effects through the use of carefully selected spectral bands, and a new "along-track" scanning technique. This involves viewing the same geophysical scene at two different angles, hence using two different atmospheric paths, so that the difference in radiative signal from the two scenes is due only to atmospheric effects, which can then be quantitatively estimated. ATSR is also a high performance radiometer, and embodies two important technological features; the first of these is the use of closed-cycle coolers, especially developed for space applications, and which were used to cool the sensitive infrared detectors. The radiometer also incorporates two purpose-designed on-board blackbody calibration targets which will also be described in detail. These two features enable the instrument to meet the stringent requirements of sensitivity and absolute radiometric accuracy demanded by this application. ATSR also incorporates a passive nadir-viewing two-channel microwave sounder. Measurements from this instrument will enable total atmospheric water vapour to be inferred, which will not only lead to improved SST retrievals, but will also considerably improve the atmospheric range correction required by the ERS-1 radar altimeter. ATSR is provided by a consortium of research institutes including the University of Oxford, Department of Atmospheric Oceanic and Planetary Physics, who are primarily responsible for scientific calibration of the instrument; University College London's Mullard Space Science Laboratory, who are responsible for the development of the blackbodies; the UK Meteorological Office, whose contributions include the focal plane assembly; the French laboratory CRPE, who are

  2. Radiometers for radon concentration in air

    International Nuclear Information System (INIS)

    Bartak, J.; Machaj, B.; Pienkos, J.P.

    2002-01-01

    Constant grow of science and technology stimulates development of new improved measuring tools. New measuring demand arise also in radon concentration measurements. Varying rock stress and rock cracks influencing radon emanation encouraged research aimed at use of this phenomenon to predict crumps of mine formation among others based on variation of radon emanation. A measuring set was developed in the Institute of Nuclear Chemistry and Technology enabling long term monitoring of radon concentration in mine bore-hole. The set consists probe and probe controller. Detection threshold of the probe is 230 Bq/m 3 . The set can operate in the environment with methane explosion hazard. A radiometer employing Lucas cell as radiation detector for radon concentration in air was also developed its detection threshold is approx. 10 Bq/m 3 . Replaceable Lucas cell of the radiometer allows for measurement of high as well as low radon concentration in short time interval. (author)

  3. Monolithic microwave integrated circuit water vapor radiometer

    Science.gov (United States)

    Sukamto, L. M.; Cooley, T. W.; Janssen, M. A.; Parks, G. S.

    1991-01-01

    A proof of concept Monolithic Microwave Integrated Circuit (MMIC) Water Vapor Radiometer (WVR) is under development at the Jet Propulsion Laboratory (JPL). WVR's are used to remotely sense water vapor and cloud liquid water in the atmosphere and are valuable for meteorological applications as well as for determination of signal path delays due to water vapor in the atmosphere. The high cost and large size of existing WVR instruments motivate the development of miniature MMIC WVR's, which have great potential for low cost mass production. The miniaturization of WVR components allows large scale deployment of WVR's for Earth environment and meteorological applications. Small WVR's can also result in improved thermal stability, resulting in improved calibration stability. Described here is the design and fabrication of a 31.4 GHz MMIC radiometer as one channel of a thermally stable WVR as a means of assessing MMIC technology feasibility.

  4. Intersatellite Calibration of Microwave Radiometers for GPM

    Science.gov (United States)

    Wilheit, T. T.

    2010-12-01

    The aim of the GPM mission is to measure precipitation globally with high temporal resolution by using a constellation of satellites logically united by the GPM Core Satellite which will be in a non-sunsynchronous, medium inclination orbit. The usefulness of the combined product depends on the consistency of precipitation retrievals from the various microwave radiometers. The calibration requirements for this consistency are quite daunting requiring a multi-layered approach. The radiometers can vary considerably in their frequencies, view angles, polarizations and spatial resolutions depending on their primary application and other constraints. The planned parametric algorithms will correct for the varying viewing parameters, but they are still vulnerable to calibration errors, both relative and absolute. The GPM Intersatellite Calibration Working Group (aka X-CAL) will adjust the calibration of all the radiometers to a common consensus standard for the GPM Level 1C product to be used in precipitation retrievals. Finally, each Precipitation Algorithm Working Group must have its own strategy for removing the residual errors. If the final adjustments are small, the credibility of the precipitation retrievals will be enhanced. Before intercomparing, the radiometers must be self consistent on a scan-wise and orbit-wise basis. Pre-screening for this consistency constitutes the first step in the intercomparison. The radiometers are then compared pair-wise with the microwave radiometer (GMI) on the GPM Core Satellite. Two distinct approaches are used for sake of cross-checking the results. On the one hand, nearly simultaneous observations are collected at the cross-over points of the orbits and the observations of one are converted to virtual observations of the other using a radiative transfer model to permit comparisons. The complementary approach collects histograms of brightness temperature from each instrument. In each case a model is needed to translate the

  5. A radiometer for stochastic gravitational waves

    International Nuclear Information System (INIS)

    Ballmer, Stefan W

    2006-01-01

    The LIGO Scientific Collaboration recently reported a new upper limit on an isotropic stochastic background of gravitational waves obtained based on the data from the third LIGO science run (S3). Here I present a new method for obtaining directional upper limits on stochastic gravitational waves that essentially implements a gravitational wave radiometer. The LIGO Scientific Collaboration intends to use this method for future LIGO science runs

  6. LAMMR: A new generation satellite microwave radiometer - Its concepts and capabilities. [Large Antenna Multichannel Microwave Radiometer

    Science.gov (United States)

    Walton, W. T.; Wilheit, T. T.

    1981-01-01

    Definition studies and baseline design are summarized for the proposed, and now discontinued, LAMMR. The instrument is an offset parabolic reflector with Cassegrain feeds. The three-meter aperture reflector, to be constructed using graphite-epoxy technology, rotates continuously at 0.833 rps. The scan drive subsystem includes momentum compensation for the rotating mass which includes the reflector, the support arm and Cassegrain subreflector, feed horns and radiometer. Two total power radiometers are recommended for each frequency, one each for horizontal and vertical polarizations. The selection plan, definition study specifications, LAMMR performance specifications, and predicted accuracies and resolutions after processing are shown.

  7. A horizontal vane radiometer: experiment, theory and simulation

    OpenAIRE

    Wolfe, David; Lazarra, Andres; Garcia, Alejandro

    2015-01-01

    The existence of two motive forces on a Crookes radiometer has complicated the investigation of either force independently. The thermal creep shear force in particular has been subject to differing interpretations of the direction in which it acts and its order of magnitude. In this article we provide a horizontal vane radiometer design which isolates the thermal creep shear force. The horizontal vane radiometer is explored through experiment, kinetic theory, and the Direct Simulation Monte C...

  8. Analyzing Non Stationary Processes in Radiometers

    Science.gov (United States)

    Racette, Paul

    2010-01-01

    The lack of well-developed techniques for modeling changing statistical moments in our observations has stymied the application of stochastic process theory for many scientific and engineering applications. Non linear effects of the observation methodology is one of the most perplexing aspects to modeling non stationary processes. This perplexing problem was encountered when modeling the effect of non stationary receiver fluctuations on the performance of radiometer calibration architectures. Existing modeling approaches were found not applicable; particularly problematic is modeling processes across scales over which they begin to exhibit non stationary behavior within the time interval of the calibration algorithm. Alternatively, the radiometer output is modeled as samples from a sequence random variables; the random variables are treated using a conditional probability distribution function conditioned on the use of the variable in the calibration algorithm. This approach of treating a process as a sequence of random variables with non stationary stochastic moments produce sensible predictions of temporal effects of calibration algorithms. To test these model predictions, an experiment using the Millimeter wave Imaging Radiometer (MIR) was conducted. The MIR with its two black body calibration references was configured in a laboratory setting to observe a third ultra-stable reference (CryoTarget). The MIR was programmed to sequentially sample each of the three references in approximately a 1 second cycle. Data were collected over a six-hour interval. The sequence of reference measurements form an ensemble sample set comprised of a series of three reference measurements. Two references are required to estimate the receiver response. A third reference is used to estimate the uncertainty in the estimate. Typically, calibration algorithms are designed to suppress the non stationary effects of receiver fluctuations. By treating the data sequence as an ensemble

  9. GPM GROUND VALIDATION DUAL POLARIZATION RADIOMETER GCPEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Dual Polarization Radiometer GCPEx dataset provides brightness temperature measurements at frequencies 90 GHz (not polarized) and 150 GHz...

  10. A cryogenic electrical substitution radiometer for hard X-rays

    International Nuclear Information System (INIS)

    Gerlach, M.; Krumrey, M.; Cibik, L.; Mueller, P.; Ulm, G.

    2007-01-01

    Cryogenic electrical substitution radiometers (ESR) are well established in radiometry to determine radiant power with low uncertainties from the infrared to the soft X-ray region. The absorbers are made of copper to achieve a small time constant. At higher photon energies, the use of copper prevents the operation of ESR due to increasing transmittance. A new absorber design for hard X-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at BESSY II. In the first place, extensive simulations were performed for a variety of materials and absorber geometries using the Monte Carlo simulation code Geant4. The accuracy of the simulations was verified comparing them to scattering experiments performed at a 7 T wavelength shifter beamline at BESSY II. It was shown that Geant4 describes the photo-effect, including fluorescence as well as Compton- and Rayleigh scattering, with high accuracy. The simulations and experiments resulted in an absorber with a gold base 500 μm in thickness, inclined by 30 deg., and a cylindrical shell made of copper 80 μm in thickness to reduce losses caused mainly by fluorescence. The absorber was manufactured at PTB by means of electroforming and was implemented into an existing ESR. Monochromatized synchrotron radiation of high spectral purity was used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative uncertainties below 1%

  11. A cryogenic electrical substitution radiometer for hard X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Gerlach, M. [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany)], E-mail: Martin.Gerlach@ptb.de; Krumrey, M.; Cibik, L.; Mueller, P.; Ulm, G. [Physikalisch-Technische Bundesanstalt, Abbestr. 2-12, 10587 Berlin (Germany)

    2007-09-21

    Cryogenic electrical substitution radiometers (ESR) are well established in radiometry to determine radiant power with low uncertainties from the infrared to the soft X-ray region. The absorbers are made of copper to achieve a small time constant. At higher photon energies, the use of copper prevents the operation of ESR due to increasing transmittance. A new absorber design for hard X-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at BESSY II. In the first place, extensive simulations were performed for a variety of materials and absorber geometries using the Monte Carlo simulation code Geant4. The accuracy of the simulations was verified comparing them to scattering experiments performed at a 7 T wavelength shifter beamline at BESSY II. It was shown that Geant4 describes the photo-effect, including fluorescence as well as Compton- and Rayleigh scattering, with high accuracy. The simulations and experiments resulted in an absorber with a gold base 500 {mu}m in thickness, inclined by 30 deg., and a cylindrical shell made of copper 80 {mu}m in thickness to reduce losses caused mainly by fluorescence. The absorber was manufactured at PTB by means of electroforming and was implemented into an existing ESR. Monochromatized synchrotron radiation of high spectral purity was used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative uncertainties below 1%.

  12. A cryogenic electrical substitution radiometer for hard X-rays

    Science.gov (United States)

    Gerlach, M.; Krumrey, M.; Cibik, L.; Müller, P.; Ulm, G.

    2007-09-01

    Cryogenic electrical substitution radiometers (ESR) are well established in radiometry to determine radiant power with low uncertainties from the infrared to the soft X-ray region. The absorbers are made of copper to achieve a small time constant. At higher photon energies, the use of copper prevents the operation of ESR due to increasing transmittance. A new absorber design for hard X-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at BESSY II. In the first place, extensive simulations were performed for a variety of materials and absorber geometries using the Monte Carlo simulation code Geant4. The accuracy of the simulations was verified comparing them to scattering experiments performed at a 7 T wavelength shifter beamline at BESSY II. It was shown that Geant4 describes the photo-effect, including fluorescence as well as Compton- and Rayleigh scattering, with high accuracy. The simulations and experiments resulted in an absorber with a gold base 500 μm in thickness, inclined by 30°, and a cylindrical shell made of copper 80 μm in thickness to reduce losses caused mainly by fluorescence. The absorber was manufactured at PTB by means of electroforming and was implemented into an existing ESR. Monochromatized synchrotron radiation of high spectral purity was used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative uncertainties below 1%.

  13. Usefulness of the infrared heterodyne radiometer in remote sensing of atmospheric pollutants.

    Science.gov (United States)

    Menzies, R. T.; Shumate, M. S.

    1971-01-01

    The application of narrow-band optical receivers to the problem of sensing atmospheric pollution is discussed. The emission/absorption lines of many major atmospheric pollutant molecules overlap the operating frequency bands of CO2 laser and CO laser heterodyne receivers. Several remote pollution sensing systems which are based upon utilization of these spectral overlaps are described, and an analysis of their potential is presented. The possibility of using other lasers (e.g.: the PbSnTe tunable diode laser) as local oscillators is also considered. Results of laboratory experiments with a CO2 laser heterodyne radiometer are presented.

  14. Global silicate mineralogy of the Moon from the Diviner lunar radiometer.

    Science.gov (United States)

    Greenhagen, Benjamin T; Lucey, Paul G; Wyatt, Michael B; Glotch, Timothy D; Allen, Carlton C; Arnold, Jessica A; Bandfield, Joshua L; Bowles, Neil E; Donaldson Hanna, Kerri L; Hayne, Paul O; Song, Eugenie; Thomas, Ian R; Paige, David A

    2010-09-17

    We obtained direct global measurements of the lunar surface using multispectral thermal emission mapping with the Lunar Reconnaissance Orbiter Diviner Lunar Radiometer Experiment. Most lunar terrains have spectral signatures that are consistent with known lunar anorthosite and basalt compositions. However, the data have also revealed the presence of highly evolved, silica-rich lunar soils in kilometer-scale and larger exposures, expanded the compositional range of the anorthosites that dominate the lunar crust, and shown that pristine lunar mantle is not exposed at the lunar surface at the kilometer scale. Together, these observations provide compelling evidence that the Moon is a complex body that has experienced a diverse set of igneous processes.

  15. Microfluidic Radiometal Labeling Systems for Biomolecules

    Energy Technology Data Exchange (ETDEWEB)

    Reichert, D E; Kenis, P J. A.

    2011-12-29

    In a typical labeling procedure with radiometals, such as Cu-64 and Ga-68; a very large (~ 100-fold) excess of the non-radioactive reactant (precursor) is used to promote rapid and efficient incorporation of the radioisotope into the PET imaging agent. In order to achieve high specific activities, careful control of reaction conditions and extensive chromatographic purifications are required in order to separate the labeled compounds from the cold precursors. Here we propose a microfluidic approach to overcome these problems, and achieve high specific activities in a more convenient, semi-automated fashion and faster time frame. Microfluidic reactors, consisting of a network of micron-sized channels (typical dimensions in the range 10 - 300¼m), filters, separation columns, electrodes and reaction loops/chambers etched onto a solid substrate, are now emerging as an extremely useful technology for the intensification and miniaturization of chemical processes. The ability to manipulate, process and analyze reagent concentrations and reaction interfaces in both space and time within the channel network of a microreactor provides the fine level of reaction control that is desirable in PET radiochemistry practice. These factors can bring radiometal labeling, specifically the preparation of radio-labeled biomolecules such as antibodies, much closer to their theoretical maximum specific activities.

  16. Vitamin D synthesis measured with a multiband filter radiometer in Río Gallegos, Argentina

    Science.gov (United States)

    Orte, Facundo; Wolfram, Elian; Salvador, Jacobo; D'Elia, Raúl; Bulnes, Daniela; Leme, N. Paes; Quel, Eduardo

    2013-05-01

    Vitamin D plays an important role in human health. Vitamin D production from the sun is affected by UVB solar radiation. This paper presents a simple method for retrieving vitamin D-weighted UV by using a multiband filter radiometer GUV-541 installed at the Atmospheric Observatory of Southern Patagonia (OAPA) (51 ° 33' S, 69° 19' W), Río Gallegos. The methodology used combines irradiance measurements from a multiband filter radiometer with spectral irradiance modeled by the SOS radiative transfer code (developed by Lille University of Science and Technology (USTL)). The spectrum modeled is weighted with vitamin D action spectra published by the International Commission on Illumination (CIE), which describes the relative effectiveness of different wavelengths in the generation of this particular biological response. This method is validated using the vitamin D-weighted UV derived from a Brewer MKIII spectrophotometer (SN 124) belonging to the National Institute for Spatial Research (INPE), Brazil, which is able to measure solar spectra between 290 and 325nm. The method presents a good correlation between the two independent instruments. This procedure increases the instrumental capabilities of the multiband filter radiometer. Moreover, it evaluates the annual variation of vitamin D-weighted UV doses from exposure to ultraviolet radiation. These values are likely to be lower than suitable levels of vitamin D during winter and part of spring and autumn at these latitudes.

  17. Calibration of the TUD Ku-band Synthetic Aperture Radiometer

    DEFF Research Database (Denmark)

    Laursen, Brian; Skou, Niels

    1995-01-01

    The TUD Synthetic Aperture Radiometer is a 2-channel demonstration model that can simulate a thinned aperture radiometer having an unfilled aperture consisting of several small antenna elements. Aperture synthesis obtained by interferometric measurements using the antenna elements in pairs, follo...

  18. The DC-8 Submillimeter-Wave Cloud Ice Radiometer

    Science.gov (United States)

    Walter, Steven J.; Batelaan, Paul; Siegel, Peter; Evans, K. Franklin; Evans, Aaron; Balachandra, Balu; Gannon, Jade; Guldalian, John; Raz, Guy; Shea, James

    2000-01-01

    An airborne radiometer is being developed to demonstrate the capability of radiometry at submillimeter-wavelengths to characterize cirrus clouds. At these wavelengths, cirrus clouds scatter upwelling radiation from water vapor in the lower troposphere. Radiometric measurements made at multiple widely spaced frequencies permit flux variations caused by changes in scattering due to crystal size to be distinguished from changes in cloud ice content. Measurements at dual polarizations can also be used to constrain the mean crystal shape. An airborne radiometer measuring the upwelling submillimeter-wave flux should then able to retrieve both bulk and microphysical cloud properties. The radiometer is being designed to make measurements at four frequencies (183 GHz, 325 GHz, 448 GHz, and 643 GHz) with dual-polarization capability at 643 GHz. The instrument is being developed for flight on NASA's DC-8 and will scan cross-track through an aircraft window. Measurements with this radiometer in combination with independent ground-based and airborne measurements will validate the submillimeter-wave radiometer retrieval techniques. The goal of this effort is to develop a technique to enable spaceborne characterization of cirrus, which will meet a key climate measurement need. The development of an airborne radiometer to validate cirrus retrieval techniques is a critical step toward development of spaced-based radiometers to investigate and monitor cirrus on a global scale. The radiometer development is a cooperative effort of the University of Colorado, Colorado State University, Swales Aerospace, and Jet Propulsion Laboratory and is funded by the NASA Instrument Incubator Program.

  19. L-Band Polarimetric Correlation Radiometer with Subharmonic Sampling

    DEFF Research Database (Denmark)

    Rotbøll, Jesper; Søbjærg, Sten Schmidl; Skou, Niels

    2001-01-01

    A novel L-band radiometer trading analog complexity for digital ditto has been designed and built. It is a fully polarimetric radiometer of the correlation type and it is based on the sub-harmonic sampling principle in which the L-band signal is directly sampled by a fast A to D converter...

  20. Novel multi-beam radiometers for accurate ocean surveillance

    DEFF Research Database (Denmark)

    Cappellin, C.; Pontoppidan, K.; Nielsen, P. H.

    2014-01-01

    Novel antenna architectures for real aperture multi-beam radiometers providing high resolution and high sensitivity for accurate sea surface temperature (SST) and ocean vector wind (OVW) measurements are investigated. On the basis of the radiometer requirements set for future SST/OVW missions...

  1. A novel L-band polarimetric radiometer featuring subharmonic sampling

    DEFF Research Database (Denmark)

    Rotbøll, J.; Søbjærg, Sten Schmidl; Skou, Niels

    2003-01-01

    A novel L-band radiometer trading analog components for digital circuits has been designed, built and operated. It is a fully polarimetric radiometer of the correlation type, and it is based on the subharmonic sampling principle in which the L-band signal is directly sampled by a fast A to D...

  2. Etched track radiometers in radon measurements: a review

    CERN Document Server

    Nikolaev, V A

    1999-01-01

    Passive radon radiometers, based on alpha particle etched track detectors, are very attractive for the assessment of radon exposure. The present review considers various devices used for measurement of the volume activity of radon isotopes and their daughters and determination of equilibrium coefficients. Such devices can be classified into 8 groups: (i) open or 'bare' detectors, (ii) open chambers, (iii) sup 2 sup 2 sup 2 Rn chambers with an inlet filter, (iv) advanced sup 2 sup 2 sup 2 Rn radiometers, (v) multipurpose radiometers, (vi) radiometers based on a combination of etched track detectors and an electrostatic field, (vii) radiometers based on etched track detectors and activated charcoal and (viii) devices for the measurement of radon isotopes and/or radon daughters by means of track parameter measurements. Some of them such as the open detector and the chamber with an inlet filter have a variety of modifications and are applied widely both in geophysical research and radon dosimetric surveys. At the...

  3. MCM Polarimetric Radiometers for Planar Arrays

    Science.gov (United States)

    Kangaslahti, Pekka; Dawson, Douglas; Gaier, Todd

    2007-01-01

    A polarimetric radiometer that operates at a frequency of 40 GHz has been designed and built as a prototype of multiple identical units that could be arranged in a planar array for scientific measurements. Such an array is planned for use in studying the cosmic microwave background (CMB). All of the subsystems and components of this polarimetric radiometer are integrated into a single multi-chip module (MCM) of substantially planar geometry. In comparison with traditional designs of polarimetric radiometers, the MCM design is expected to greatly reduce the cost per unit in an array of many such units. The design of the unit is dictated partly by a requirement, in the planned CMB application, to measure the Stokes parameters I, Q, and U of the CMB radiation with high sensitivity. (A complete definition of the Stokes parameters would exceed the scope of this article. In necessarily oversimplified terms, I is a measure of total intensity of radiation, while Q and U are measures of the relationships between the horizontally and vertically polarized components of radiation.) Because the sensitivity of a single polarimeter cannot be increased significantly, the only way to satisfy the high-sensitivity requirement is to make a large array of polarimeters that operate in parallel. The MCM includes contact pins that can be plugged into receptacles on a standard printed-circuit board (PCB). All of the required microwave functionality is implemented within the MCM; any required supporting non-microwave ("back-end") electronic functionality, including the provision of DC bias and control signals, can be implemented by standard PCB techniques. On the way from a microwave antenna to the MCM, the incoming microwave signal passes through an orthomode transducer (OMT), which splits the radiation into an h + i(nu) beam and an h - i(nu) beam (where, using complex-number notation, h denotes the horizontal component, nu denotes the vertical component, and +/-i denotes a +/-90deg phase

  4. Microwave integrated circuit radiometer front-ends for the Push Broom Microwave Radiometer

    Science.gov (United States)

    Harrington, R. F.; Hearn, C. P.

    1982-01-01

    Microwave integrated circuit front-ends for the L-band, S-band and C-band stepped frequency null-balanced noise-injection Dicke-switched radiometer to be installed in the NASA Langley airborne prototype Push Broom Microwave Radiometer (PBMR) are described. These front-ends were developed for the fixed frequency of 1.413 GHz and the variable frequencies of 1.8-2.8 GHz and 3.8-5.8 GHz. Measurements of the noise temperature of these units were made at 55.8 C, and the results of these tests are given. While the overall performance was reasonable, improvements need to be made in circuit losses and noise temperatures, which in the case of the C-band were from 1000 to 1850 K instead of the 500 K specified. Further development of the prototypes is underway to improve performance and extend the frequency range.

  5. Dual-Polarization, Multi-Frequency Antenna Array for use with Hurricane Imaging Radiometer

    Science.gov (United States)

    Little, John

    2013-01-01

    Advancements in common aperture antenna technology were employed to utilize its proprietary genetic algorithmbased modeling tools in an effort to develop, build, and test a dual-polarization array for Hurricane Imaging Radiometer (HIRAD) applications. Final program results demonstrate the ability to achieve a lightweight, thin, higher-gain aperture that covers the desired spectral band. NASA employs various passive microwave and millimeter-wave instruments, such as spectral radiometers, for a range of remote sensing applications, from measurements of the Earth's surface and atmosphere, to cosmic background emission. These instruments such as the HIRAD, SFMR (Stepped Frequency Microwave Radiometer), and LRR (Lightweight Rainfall Radiometer), provide unique data accumulation capabilities for observing sea surface wind, temperature, and rainfall, and significantly enhance the understanding and predictability of hurricane intensity. These microwave instruments require extremely efficient wideband or multiband antennas in order to conserve space on the airborne platform. In addition, the thickness and weight of the antenna arrays is of paramount importance in reducing platform drag, permitting greater time on station. Current sensors are often heavy, single- polarization, or limited in frequency coverage. The ideal wideband antenna will have reduced size, weight, and profile (a conformal construct) without sacrificing optimum performance. The technology applied to this new HIRAD array will allow NASA, NOAA, and other users to gather information related to hurricanes and other tropical storms more cost effectively without sacrificing sensor performance or the aircraft time on station. The results of the initial analysis and numerical design indicated strong potential for an antenna array that would satisfy all of the design requirements for a replacement HIRAD array. Multiple common aperture antenna methodologies were employed to achieve exceptional gain over the entire

  6. Mapping global precipitation with satellite borne microwave radiometer and infrared radiometer using Kalman filter

    International Nuclear Information System (INIS)

    Noda, S.; Sasashige, K.; Katagami, D.; Ushio, T.; Kubota, T.; Okamoto, K.; Iida, Y.; Kida, S.; Shige, S.; Shimomura, S.; Aonashi, K.; Inoue, T.; Morimoto, T.; Kawasaki, Z.

    2007-01-01

    Estimates of precipitation at a high time and space resolution are required for many important applications. In this paper, a new global precipitation map with high spatial (0.1 degree) and temporal (1 hour) resolution using Kalman filter technique is presented and evaluated. Infrared radiometer data, which are available globally nearly everywhere and nearly all the time from geostationary orbit, are used with the several microwave radiometers aboard the LEO satellites. IR data is used as a means to move the precipitation estimates from microwave observation during periods when microwave data are not available at a given location. Moving vector is produced by computing correlations on successive images of IR data. When precipitation is moved, the Kalman filter is applied for improving the moving technique in this research. The new approach showed a better score than the technique without Kalman filter. The correlation coefficient was 0.1 better than without the Kalman filter about 6 hours after the last microwave overpasses, and the RMS error was improved about 0.1 mm/h with the Kalman filter technique. This approach is unique in that 1) the precipitation estimates from the microwave radiometer is mainly used, 2) the IR temperature in every hour is also used for the precipitation estimates based on the Kalman filter theory

  7. Soil Moisture Active Passive (SMAP) Microwave Radiometer Radio-Frequency Interference (RFI) Mitigation: Initial On-Orbit Results

    Science.gov (United States)

    Mohammed, Priscilla N.; Piepmeier, Jeffrey R.; Johnson, Joel T.; Aksoy, Mustafa; Bringer, Alexandra

    2015-01-01

    The Soil Moisture Active Passive (SMAP) mission, launched in January 2015, provides global measurements of soil moisture using a microwave radiometer. SMAPs radiometer passband lies within the passive frequency allocation. However, both unauthorized in-band transmitters as well as out-of-band emissions from transmitters operating at frequencies adjacent to this allocated spectrum have been documented as sources of radio frequency interference (RFI) to the L-band radiometers on SMOS and Aquarius. The spectral environment consists of high RFI levels as well as significant occurrences of low level RFI equivalent to 0.1 to 10 K. The SMAP ground processor reports the antenna temperature both before and after RFI mitigation is applied. The difference between these quantities represents the detected RFI level. The presentation will review the SMAP RFI detection and mitigation procedure and discuss early on-orbit RFI measurements from the SMAP radiometer. Assessments of global RFI properties and source types will be provided, as well as the implications of these results for SMAP soil moisture measurements.

  8. SAFARI 2000 Atmospheric Aerosol Measurements, Hand-held Hazemeters, Zambia

    Data.gov (United States)

    National Aeronautics and Space Administration — In conjunction with the AERONET (AErosol RObotic NETwork) participation in SAFARI 2000, the USDA Forest Service deployed handheld hazemeters in western Zambia from...

  9. 3D interactive topology optimization on hand-held devices

    DEFF Research Database (Denmark)

    Nobel-Jørgensen, Morten; Aage, Niels; Christiansen, Asger Nyman

    2015-01-01

    This educational paper describes the implementation aspects, user interface design considerations and workflow potential of the recently published TopOpt 3D App. The app solves the standard minimum compliance problem in 3D and allows the user to change design settings interactively at any point...... in time during the optimization. Apart from its educational nature, the app may point towards future ways of performing industrial design. Instead of the usual geometrize, then model and optimize approach, the geometry now automatically adapts to the varying boundary and loading conditions. The app...

  10. Enhanced operator interface for hand-held landmine detector

    Science.gov (United States)

    Herman, Herman; McMahill, Jeffrey D.; Kantor, George

    2001-10-01

    As landmines get harder to detect, the complexity of landmine detectors has also been increasing. To increase the probability of detection and decrease the false alarm rate of low metallic landmines, many detectors employ multiple sensing modalities, which include radar and metal detector. Unfortunately, the operator interface for these new detectors stays pretty much the same as for the older detectors. Although the amount of information that the new detectors acquire has increased significantly, the interface has been limited to a simple audio interface. We are currently developing a hybrid audiovisual interface for enhancing the overall performance of the detector. The hybrid audiovisual interface combines the simplicity of the audio output with the rich spatial content of the video display. It is designed to optimally present the output of the detector and also to give the proper feedback to the operator. Instead of presenting all the data to the operator simultaneously, the interface allows the operator to access the information as needed. This capability is critical to avoid information overload, which can significantly reduce the performance of the operator. The audio is used as the primary notification signal, while the video is used for further feedback, discrimination, localization and sensor fusion. The idea is to let the operator gets the feedback that he needs and enable him to look at the data in the most efficient way. We are also looking at a hybrid man-machine detection system which utilizes precise sweeping by the machine and powerful human cognitive ability. In such a hybrid system, the operator is free to concentrate on discriminant task, such as manually fusing the output of the different sensing modalities, instead of worrying about the proper sweep technique. In developing this concept, we have been using the virtual mien lane to validate some of these concepts. We obtained some very encouraging results form our preliminary test. It clearly shows that with the proper feedback, the performance of the operator can be improved significantly in a very short time.

  11. SAFARI 2000 Atmospheric Aerosol Measurements, Hand-held Hazemeters, Zambia

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: In conjunction with the AERONET (AErosol RObotic NETwork) participation in SAFARI 2000, the USDA Forest Service deployed handheld hazemeters in western...

  12. Chameleon-reconfigurability in hand-held multimedia computers

    NARCIS (Netherlands)

    Smit, Gerardus Johannes Maria; Bos, M.; Havinga, Paul J.M.; Smit, Jaap; Mullender, Sape J.; Gellersen, H.W.

    In this paper a reconfigurable systems-architecture in combination with a QoS driven operating system is introduced that can deal with the inherent dynamics of future mobile systems. We claim that a radical new approach has to be taken in order to fulfill the requirements - in terms of processing

  13. On the use of hand-held magnifiers during reading

    NARCIS (Netherlands)

    Neve, J.J.

    1989-01-01

    Little is known about the actual use of magnifiers (or loupes) during reading. In studying the influence of the use of magnifiers on the reading process the reading field is a relevant factor. Four reading fields are distinguished: three horizontal reading fields and the vertical reading field. We

  14. A hand held photo identity verification system for mobile applications

    International Nuclear Information System (INIS)

    Kumar, Ranajit; Upreti, Anil; Mahaptra, U.; Bhattacharya, S.; Srivastava, G.P.

    2009-01-01

    A handheld portable system has been developed for mobile personnel identity verification. The system consists of a contact less RF smart card reader integrated to a Simputer through serial link. The simputer verifies the card data, with the data base and aids the security operator in identifying the persons by providing the facial image of the verified person along with other personal details like name, designation, division etc. All transactions are recorded in the Simputer with time and date for future record. This system finds extensive applications in mobile identity verification in nuclear or other industries. (author)

  15. Absorption Related to Hand-Held Devices in Data Mode

    DEFF Research Database (Denmark)

    Andersen, Jørgen Bach; Nielsen, Jesper Ødum; Pedersen, Gert F.

    2016-01-01

    The human body has an influence on the radiation from handheld devices like smartphones, tablets and laptops, part of the energy is absorbed and the spatial distribution of the radiated part is modified. Previous studies of whole body absorp- tion have mainly been numerical or related to talk mode....... In the present paper an experimental study involving four volunteers and three different devices is performed from 0.5 to 3 GHz. The devices are a laptop, a tablet, and a smartphone all held in the lap. The 3D distribution of radiation is measured. Comparing the integrated power in the case of a person present...

  16. Stimulus intensity for hand held and robotic transcranial magnetic stimulation.

    Science.gov (United States)

    Richter, Lars; Trillenberg, Peter; Schweikard, Achim; Schlaefer, Alexander

    2013-05-01

    Transcranial Magnetic Stimulation (TMS) is based on a changing magnetic field inducing an electric field in the brain. Conventionally, the TMS coil is mounted to a static holder and the subject is asked to avoid head motion. Additionally, head resting frames have been used. In contrast, our robotized TMS system employs active motion compensation (MC) to maintain the correct coil position. We study the effect of patient motion on TMS. In particular, we compare different coil positioning techniques with respect to the induced electric field. We recorded head motion for six subjects in three scenarios: (a) avoiding head motion, (b) using a head rest, and (c) moving the head freely. Subsequently, the motion traces were replayed using a second robot to move a sensor to measure the electric field in the target region. These head movements were combined with 2 types of coil positioning: (1) using a coil holder and (2) using robotized TMS with MC. After 30 min the induced electric field was reduced by 32.0% and 19.7% for scenarios (1a) and (1b), respectively. For scenarios (2a)-(2c) it was reduced by only 4.9%, 1.4% and 2.0%, respectively, which is a significant improvement (P < 0.05). Furthermore, the orientation of the induced field changed by 5.5°, 7.6°, 0.4°, 0.2°, 0.2° for scenarios (1a)-(2c). While none of the scenarios required rigid head fixation, using a simple holder to position a coil during TMS can lead to substantial deviations in the induced electric field. In contrast, robotic motion compensation results in clinically acceptable positioning throughout treatment. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Real-Time Hand-Held Magnetometer Array

    Science.gov (United States)

    2016-04-01

    measurements, we swung a target, pendulum-style, from the ceiling above the array. We could easily observe that the height of the target was varying... crystal oscillator clock signal. The Microblaze processor boots up with the program already present in its RAM at startup. MR-2104 Real-Time

  18. Monitoring invasive plants using hand-held GIS technology

    Science.gov (United States)

    Theresa M. Mau-Crimmins; Barron J. Orr

    2005-01-01

    Successful control of invasive species requires a clear picture of the spatial extent of infestations. The latest mapping technology involves coupling global position systems and handheld computers running geographic information systems software in the field. A series of workshops applying this technology to mapping weeds was developed and presented to Weed Management...

  19. Development of a hand-held fast neutron survey meter

    International Nuclear Information System (INIS)

    Yoshida, T.; Tsujimura, N.; Yamano, T.

    2011-01-01

    A neutron survey meter with a ZnS(Ag) scintillator to measure recoil protons was built. The detection probe weighs ∼2 kg, therefore providing us with true portability. Performance tests exhibited satisfactory neutron dosimetry characteristics in unmoderated or lightly moderated fission neutron fields and in particular work environments at a mixed oxide fuel facility. This new survey meter will augment a routine of neutron monitoring that is inconveniently being carried out by moderator-based neutron survey meters. (authors)

  20. Testing of Hand-Held Mine Detection Systems

    Science.gov (United States)

    2015-01-08

    Military Standards (MIL-STD), and if necessary, International Test Operations Procedures (ITOP) and North Atlantic Treaty Organization (NATO...include grass vegetation, loose and compacted ground, virgin ground, controlled wash beds. Allow for a calibration to be available for each type of...MSDS material safety data sheet N North NATO North Atlantic Treaty Organization NBC nuclear, biological, chemical NMMC no metal main charge NMPP

  1. Vibration produced by hand-held olive electrical harvesters

    Directory of Open Access Journals (Sweden)

    Emanuele Cerruto

    2012-09-01

    Full Text Available The paper reports the results of some laboratory and field tests aimed at assessing the acceleration levels transmitted to the hand-arm system by electric portable harvesters for olive. Four harvesting heads, different for shape and kinematic system, and five bars, different for diameter, length and material (aluminium and carbon fibre, were used in assembling eleven harvesters. The vibrations were measured in two points, next to the handgrips. The laboratory tests allowed the evaluation of the acceleration levels in standard controlled conditions, while the field tests allowed the assessing of the effects of the tree canopy with respect to the no load running. The laboratory tests showed that in reducing the vibration level plays a major role the kinematic system of the harvesting head and then the bar material. The classical flap-type harvester produced accelerations of around 20 m/s2, while by using a harvesting head with two parts in opposite movement, the accelerations were lowered to about 6 m/s2. The use of carbon fibres for the bars, besides the reduction in weight, produced also a reduction in acceleration (from 21 to 16 m/s2. The field tests proved that the tree canopy had a negative effect on the vibrations transmitted to the hand-arm system, especially when the aluminium bar of small diameter was used.

  2. Calibration of Correlation Radiometers Using Pseudo-Random Noise Signals

    Directory of Open Access Journals (Sweden)

    Sebastián Pantoja

    2009-08-01

    Full Text Available The calibration of correlation radiometers, and particularly aperture synthesis interferometric radiometers, is a critical issue to ensure their performance. Current calibration techniques are based on the measurement of the cross-correlation of receivers’ outputs when injecting noise from a common noise source requiring a very stable distribution network. For large interferometric radiometers this centralized noise injection approach is very complex from the point of view of mass, volume and phase/amplitude equalization. Distributed noise injection techniques have been proposed as a feasible alternative, but are unable to correct for the so-called “baseline errors” associated with the particular pair of receivers forming the baseline. In this work it is proposed the use of centralized Pseudo-Random Noise (PRN signals to calibrate correlation radiometers. PRNs are sequences of symbols with a long repetition period that have a flat spectrum over a bandwidth which is determined by the symbol rate. Since their spectrum resembles that of thermal noise, they can be used to calibrate correlation radiometers. At the same time, since these sequences are deterministic, new calibration schemes can be envisaged, such as the correlation of each receiver’s output with a baseband local replica of the PRN sequence, as well as new distribution schemes of calibration signals. This work analyzes the general requirements and performance of using PRN sequences for the calibration of microwave correlation radiometers, and particularizes the study to a potential implementation in a large aperture synthesis radiometer using an optical distribution network.

  3. Soil moisture mapping at Bubnow Wetland using L-band radiometer (ELBARA III)

    Science.gov (United States)

    Łukowski, Mateusz; Schwank, Mike; Szlązak, Radosław; Wiesmann, Andreas; Marczewski, Wojciech; Usowicz, Bogusław; Usowicz, Jerzy; Rojek, Edyta; Werner, Charles

    2016-04-01

    The study of soil moisture is a scientific challenge. Not only because of large diversity of soils and differences in their water content, but also due to the difficulty of measuring, especially in large scale. On this field of interest several methods to determine the content of water in soil exists. The basic and referential is gravimetric method, which is accurate, but suitable only for small spatial scales and time-consuming. Indirect methods are faster, but need to be validated, for example those based on dielectric properties of materials (e.g. time domain reflectometry - TDR) or made from distance (remote), like brightness temperature measurements. Remote sensing of soil moisture can be performed locally (from towers, drones, planes etc.) or globally (satellites). These techniques can complement and help to verify different models and assumptions. In our studies, we applied spatial statistics to local soil moisture mapping using ELBARA III (ESA L-band radiometer, 1.4 GHz) mounted on tower (6.5 meter height). Our measurements were carried out in natural Bubnow Wetland, near Polesie National Park (Eastern Poland), during spring time. This test-site had been selected because it is representative for one of the biggest wetlands in Europe (1400 km2), called "Western Polesie", localized in Ukraine, Poland and Belarus. We have investigated Bubnow for almost decade, using meteorological and soil moisture stations, conducting campaigns of hand-held measurements and collecting soil samples. Now, due to the possibility of rotation at different incidence angles (as in previous ELBARA systems) and the new azimuth tracking capabilities, we obtained brightness temperature data not only at different distances from the tower, but also around it, in footprints containing different vegetation and soil types. During experiment we collected data at area about 450 m2 by rotating ELBARA's antenna 5-175° in horizontal and 30-70° in vertical plane. This type of approach allows

  4. Aquarius L-Band Radiometers Calibration Using Cold Sky Observations

    Science.gov (United States)

    Dinnat, Emmanuel P.; Le Vine, David M.; Piepmeier, Jeffrey R.; Brown, Shannon T.; Hong, Liang

    2015-01-01

    An important element in the calibration plan for the Aquarius radiometers is to look at the cold sky. This involves rotating the satellite 180 degrees from its nominal Earth viewing configuration to point the main beams at the celestial sky. At L-band, the cold sky provides a stable, well-characterized scene to be used as a calibration reference. This paper describes the cold sky calibration for Aquarius and how it is used as part of the absolute calibration. Cold sky observations helped establish the radiometer bias, by correcting for an error in the spillover lobe of the antenna pattern, and monitor the long-term radiometer drift.

  5. Special aerosol sources for certification and test of aerosol radiometers

    International Nuclear Information System (INIS)

    Belkina, S.K.; Zalmanzon, Y.E.; Kuznetsov, Y.V.; Rizin, A.I.; Fertman, D.E.

    1991-01-01

    The results are presented of the development and practical application of new radionuclide source types (Special Aerosol Sources (SAS)), that meet the international standard recommendations, which are used for certification and test of aerosol radiometers (monitors) using model aerosols of plutonium-239, strontium-yttrium-90 or uranium of natural isotope composition and certified against Union of Soviet Socialist Republics USSR national radioactive aerosol standard or by means of a reference radiometer. The original technology for source production allows the particular features of sampling to be taken into account as well as geometry and conditions of radionuclides radiation registration in the sample for the given type of radiometer. (author)

  6. Special aerosol sources for certification and test of aerosol radiometers

    Energy Technology Data Exchange (ETDEWEB)

    Belkina, S.K.; Zalmanzon, Y.E.; Kuznetsov, Y.V.; Rizin, A.I.; Fertman, D.E. (Union Research Institute of Instrumentation, Moscow (USSR))

    1991-01-01

    The results are presented of the development and practical application of new radionuclide source types (Special Aerosol Sources (SAS)), that meet the international standard recommendations, which are used for certification and test of aerosol radiometers (monitors) using model aerosols of plutonium-239, strontium-yttrium-90 or uranium of natural isotope composition and certified against Union of Soviet Socialist Republics USSR national radioactive aerosol standard or by means of a reference radiometer. The original technology for source production allows the particular features of sampling to be taken into account as well as geometry and conditions of radionuclides radiation registration in the sample for the given type of radiometer. (author).

  7. Multifilter Rotating Shadowband Radiometer (MFRSR) Handbook With subsections for derivative instruments: Multifilter Radiometer (MFR) Normal Incidence Multifilter Radiometer (NIMFR)

    Energy Technology Data Exchange (ETDEWEB)

    Hodges, Gary B. [National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States). Earth System Research Lab.; Michalsky, Joseph J. [National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States). Earth System Research Lab.

    2016-03-01

    The visible Multifilter Rotating Shadowband Radiometer (MFRSR) is a passive instrument that measures global and diffuse components of solar irradiance at six narrowband channels and one open, or broadband, channel (Harrison et al. 1994). Direct irradiance is not a primary measurement, but is calculated using diffuse and global measurements. To collect one data record, the MFRSR takes measurements at four different shadowband positions. The first measurement is taken with the shadowband in the nadir (home) position. The next three measurements are, in order, the first side-band, sun-blocked, and second side-band. The side-band measurements are used to correct for the portion of the sky obscured by the shadowband. The nominal wavelengths of the narrowband channels are 415, 500, 615, 673, 870, and 940 nm. From such measurements, one may infer the atmosphere’s aerosol optical depth at each wavelength. In turn, these optical depths may be used to derive information about the column abundances of ozone and water vapor (Michalsky et al. 1995), as well as aerosol (Harrison and Michalsky 1994) and other atmospheric constituents.

  8. Pushbroom microwave radiometer results from HAPEX-MOBILHY

    International Nuclear Information System (INIS)

    Nichols, W.E.; Cuenca, R.H.; Schmugge, T.J.; Wang, J.R.

    1993-01-01

    The NASA C-130 remote sensing aircraft was in Toulouse, France from 25 May through 4 July 1986, for participation in the HAPEX-MOBILHY program. Spectral and radiometric data were collected by C-130 borne sensors in the visible, infrared, and microwave wavelengths. These data provided information on the spatial and temporal variations of surface parameters such as vegetation indices, surface temperature, and surface soil moisture. The Pushbroom Microwave Radiometer (PBMR) was used to collect passive microwave brightness temperature data. This four-beam sensor operates at the 21-cm wavelength, providing cross-track coverage approximately 1.2 times the aircraft altitude. Observed brightness temperatures for the period were high, ranging from above 240 K about 290 K. Brightness temperature images appeared to correspond well to spatial and temporal soil moisture variation. Previous research has demonstrated that an approximately linear relationship exists between the surface emissivity and surface soil moisture. For these data, however, regression analysis did not indicate a strong linear relationship (r 2 = 0.32 and r 2 = 0.42 respectively) because of the limited range of soil moisture conditions encountered and the small number of ground measurements. When results from wetter soil conditions encountered in another experiment were included, the regression improved dramatically. Based on similar research with the PBMR and an understanding of the ground data collection program, this result was examined to produce recommendations for improvements to future passive microwave research and data collection programs. Examples of surface soil moisture maps generated with PBMR data are presented which appear to be representative of the actual soil moisture conditions

  9. CAROLS: A New Airborne L-Band Radiometer for Ocean Surface and Land Observations

    DEFF Research Database (Denmark)

    Zribi, Mehrez; Parde, Mickael; Boutin, Jacquline

    2011-01-01

    The "Cooperative Airborne Radiometer for Ocean and Land Studies" (CAROLS) L-Band radiometer was designed and built as a copy of the EMIRAD II radiometer constructed by the Technical University of Denmark team. It is a fully polarimetric and direct sampling correlation radiometer. It is installed ...

  10. Construction and calibration of solar radiometers: pyranometer and pyrheliometer

    International Nuclear Information System (INIS)

    Escobedo, J.F.; Passos, E.F.; Souza, M.F. de

    1988-01-01

    This paper reports the construction and development of solar radiometers and discusses some characteristic parameters such as linearity, sensitivity and time constant, using an Eppley black-and-white pyranometer as reference. (author) [pt

  11. The development of the advanced cryogenic radiometer facility at NRC

    Science.gov (United States)

    Gamouras, A.; Todd, A. D. W.; Côté, É.; Rowell, N. L.

    2018-02-01

    The National Research Council (NRC) of Canada has established a next generation facility for the primary realization of optical radiant power. The main feature of this facility is a new cryogenic electrical substitution radiometer with a closed-cycle helium cryocooler. A monochromator-based approach allows for detector calibrations at any desired wavelength. A custom-designed motion apparatus includes two transfer standard radiometer mounting ports which has increased our measurement capability by allowing the calibration of two photodetectors in one measurement cycle. Measurement uncertainties have been improved through several upgrades, including newly designed and constructed transimpedance amplifiers for the transfer standard radiometers, and a higher power broadband light source. The most significant improvements in uncertainty arise from the enhanced characteristics of the new cryogenic radiometer including its higher cavity absorptance and reduced non-equivalence effects.

  12. Hurricane Satellite (HURSAT) from Advanced Very High Resolution Radiometer (AVHRR)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Huricane Satellite (HURSAT)-Advanced Very High Resolution Radiometer (AVHRR) is used to extend the HURSAT data set such that appling the Objective Dvorak technique...

  13. Effect of Chamber Wall Proximity on Radiometer Force Production (Preprint)

    National Research Council Canada - National Science Library

    Selden, N. P; Gimelshein, N. E; Gimelshein, S. F; Ketsdever, A. D

    2008-01-01

    ... on a given radiometer configuration in both the free molecule and transitional regimes. The contribution of the chamber walls to both the flowfield structure and radiometric force production were examined for helium, argon, and nitrogen test gases...

  14. Characterization of a Compact Water Vapor Radiometer

    Science.gov (United States)

    Gill, Ajay; Selina, Rob

    2018-01-01

    We report on laboratory test results of the Compact Water Vapor Radiometer (CWVR) prototype for the Karl G. Jansky Very Large Array (VLA), a five-channel design centered around the 22 GHz water vapor line. Fluctuations in perceptible water vapor cause fluctuations in atmospheric brightness emission, which are assumed to be proportional to phase fluctuations of the astronomical signal seen by an antenna. The design is intended to support empirical radiometric phase corrections for each baseline in the array.The dynamic range, channel isolation, and gain stability of the device were characterized. The device has a useful dynamic range of order 18 dB after calibration, and the CWVR channel isolation requirement of test, the diode detectors were operated in the square-law region, and a K-band noise diode was used as the broadband input power source to the CWVR over a period of 64 hours. Results indicate that the fluctuations in output counts are negatively correlated to the CWVR enclosure ambient temperature, with a change of ~ 405 counts per 1° C change in temperature.A correction for the CWVR ambient temperature makes a considerable improvement in stability for τ > 102.6 sec. With temperature corrections, the single channel and channel difference gain stability per channel is test results indicate that the CWVR meets required specifications for dynamic range, channel isolation, and gain stability in order to proceed with testing on a pair of VLA antennas.

  15. Multifilter Rotating Shadowband Radiometer (MFRSR) Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Hodges, GB; Michalsky, JJ

    2011-02-07

    The visible Multifilter Rotating Shadowband Radiometer (MFRSR) is a passive instrument that measures global and diffuse components of solar irradiance at six narrowband channels and one open, or broadband, channel (Harrison et al. 1994). Direct irradiance is not a primary measurement, but is calculated using the diffuse and global measurements. To collect one data record, the MFRSR takes measurements at four different shadowband positions. The first measurement is taken with the shadowband in the nadir (home) position. The next three measurements are, in order, the first side-band, sun-blocked, and second side-band. The side-band measurements are used to correct for the portion of the sky obscured by the shadowband. The nominal wavelengths of the narrowband channels are 415, 500, 615, 673, 870, and 940 nm. From such measurements, one may infer the atmosphere's aerosol optical depth at each wavelength. In turn, these optical depths may be used to derive information about the column abundances of ozone and water vapor (Michalsky et al. 1995), as well as aerosol (Harrison and Michalsky 1994) and other atmospheric constituents.

  16. Sources of errors in the measurements of underwater profiling radiometer

    Digital Repository Service at National Institute of Oceanography (India)

    Silveira, N.; Suresh, T.; Talaulikar, M.; Desa, E.; Matondkar, S.G.P.; Lotlikar, A.

    to meet the stringent quality requirements of marine optical data for satellite ocean color sensor validation, development of algorithms and other related applications, it is very essential to take great care while measuring these parameters. There are two... of the pelican hook. The radiometer dives vertically and the cable is paid out with less tension, keeping in tandem with the descent of the radiometer while taking care to release only the required amount of cable. The operation of the release mechanism lever...

  17. Measurement of radiosity coefficient by means of an infrared radiometer

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Yoshizo; Kaminaga, Fumito; Osakabe, Masahiro; Maekawa, Katsuhiro [Ibaraki Univ., Hitachi (Japan). Faculty of Engineering; Ishii, Toshimitsu; Ouoka, Norikazu; Etou, Motokuni

    1991-02-01

    An infrared radiometer has been used for measuring and visualizing the radiation temperature distribution of a surface in many fields. Measured radiation energy by the radiometer is a summation of an emitted radiation and a reflection, which is called a radiosity flux. The present paper shows the characteristics of the radiosity of tested materials. The infrared sensor in used to measure the erosion rate of the graphite by ion beam injection and the temperature distribution of a cutter. (author).

  18. Measurement of radiosity coefficient by means of an infrared radiometer

    International Nuclear Information System (INIS)

    Okamoto, Yoshizo; Kaminaga, Fumito; Osakabe, Masahiro; Maekawa, Katsuhiro; Ishii, Toshimitsu; Ouoka, Norikazu; Etou, Motokuni.

    1991-01-01

    An infrared radiometer has been used for measuring and visualizing the radiation temperature distribution of a surface in many fields. Measured radiation energy by the radiometer is a summation of an emitted radiation and a reflection, which is called a radiosity flux. The present paper shows the characteristics of the radiosity of tested materials. The infrared sensor in used to measure the erosion rate of the graphite by ion beam injection and the temperature distribution of a cutter. (author)

  19. A cost effective total power radiometer package for atmospheric research

    International Nuclear Information System (INIS)

    Lyons, B.N.; Kelly, W.M.; Vizard, D.R.; Lidholm, U.S.

    1993-01-01

    Millimeter wave radiometers are being increasingly used for plasma diagnostics and remote sensing applications. To date however the widespread use of such systems, particularly for applications requiring frequency coverage above 100 GHz, have been inhibited by the lack of availability of an appropriately specified commercial package. This paper outlines the design and construction of such a radiometer package and gives details of results obtained to date

  20. Dual-Telescope Multi-Channel Thermal-Infrared Radiometer for Outer Planet Fly-By Missions

    Science.gov (United States)

    Aslam, Shahid; Amato, Michael; Bowles, Neil; Calcutt, Simon; Hewagama, Tilak; Howard, Joseph; Howett, Carly; Hsieh, Wen-Ting; Hurford, Terry; Hurley, Jane; hide

    2016-01-01

    The design of a versatile dual-telescope thermal-infrared radiometer spanning the spectral wavelength range 8-200 microns, in five spectral pass bands, for outer planet fly-by missions is described. The dual- telescope design switches between a narrow-field-of-view and a wide-field-of-view to provide optimal spatial resolution images within a range of spacecraft encounters to the target. The switchable dual-field- of-view system uses an optical configuration based on the axial rotation of a source-select mirror along the optical axis. The optical design, spectral performance, radiometric accuracy, and retrieval estimates of the instrument are discussed. This is followed by an assessment of the surface coverage performance at various spatial resolutions by using the planned NASA Europa Mission 13-F7 fly-by trajectories as a case study.

  1. Results from the Fourth WMO Filter Radiometer Comparison for aerosol optical depth measurements

    Science.gov (United States)

    Kazadzis, Stelios; Kouremeti, Natalia; Diémoz, Henri; Gröbner, Julian; Forgan, Bruce W.; Campanelli, Monica; Estellés, Victor; Lantz, Kathleen; Michalsky, Joseph; Carlund, Thomas; Cuevas, Emilio; Toledano, Carlos; Becker, Ralf; Nyeki, Stephan; Kosmopoulos, Panagiotis G.; Tatsiankou, Viktar; Vuilleumier, Laurent; Denn, Frederick M.; Ohkawara, Nozomu; Ijima, Osamu; Goloub, Philippe; Raptis, Panagiotis I.; Milner, Michael; Behrens, Klaus; Barreto, Africa; Martucci, Giovanni; Hall, Emiel; Wendell, James; Fabbri, Bryan E.; Wehrli, Christoph

    2018-03-01

    This study presents the results of the Fourth Filter Radiometer Comparison that was held in Davos, Switzerland, between 28 September and 16 October 2015. Thirty filter radiometers and spectroradiometers from 12 countries participated including reference instruments from global aerosol networks. The absolute differences of all instruments compared to the reference have been based on the World Meteorological Organization (WMO) criterion defined as follows: 95% of the measured data has to be within 0.005 ± 0.001/m (where m is the air mass). At least 24 out of 29 instruments achieved this goal at both 500 and 865 nm, while 12 out of 17 and 13 out of 21 achieved this at 368 and 412 nm, respectively. While searching for sources of differences among different instruments, it was found that all individual differences linked to Rayleigh, NO2, ozone, water vapor calculations and related optical depths and air mass calculations were smaller than 0.01 in aerosol optical depth (AOD) at 500 and 865 nm. Different cloud-detecting algorithms used have been compared. Ångström exponent calculations showed relatively large differences among different instruments, partly because of the high calculation uncertainty of this parameter in low AOD conditions. The overall low deviations of these AOD results and the high accuracy of reference aerosol network instruments demonstrated a promising framework to achieve homogeneity, compatibility and harmonization among the different spectral AOD networks in the near future.

  2. PHyTIR - A Prototype Thermal Infrared Radiometer

    Science.gov (United States)

    Jau, Bruno M.; Hook, Simon J.; Johnson, William R.; Foote, Marc C.; Paine, Christopher G.; Pannell, Zack W.; Smythe, Robert F.; Kuan, Gary M.; Jakoboski, Julie K.; Eng, Bjorn T.

    2013-01-01

    This paper describes the PHyTIR (Prototype HyspIRI Thermal Infrared Radiometer) instrument, which is the engineering model for the proposed HyspIRI (Hyperspectral Infrared Imager) earth observing instrument. The HyspIRI mission would be comprised of the HyspIRI TIR (Thermal Infrared Imager), and a VSWIR (Visible Short-Wave Infra-Red Imaging Spectrometer). Both instruments would be used to address key science questions related to the earth's carbon cycle, ecosystems, climate, and solid earth properties. Data gathering of volcanic activities, earthquakes, wildfires, water use and availability, urbanization, and land surface compositions and changes, would aid the predictions and evaluations of such events and the impact they create. Even though the proposed technology for the HyspIRI imager is mature, the PHyTIR prototype is needed to advance the technology levels for several of the instrument's key components, and to reduce risks, in particular to validate 1) the higher sensitivity, spatial resolution, and higher throughput required for this focal plane array, 2) the pointing accuracy, 2) the characteristics of several spectral channels, and 4) the use of ambient temperature optics. The PHyTIR telescope consists of the focal plane assembly that is housed within a cold housing located inside a vacuum enclosure; all mounted to a bulkhead, and an optical train that consists of 3 powered mirrors; extending to both sides of the bulkhead. A yoke connects the telescope to a scan mirror. The rotating mirror enables to scan- a large track on the ground. This structure is supported by kinematic mounts, linking the telescope assembly to a base plate that would also become the spacecraft interface for HyspIRI. The focal plane's cooling units are also mounted to the base plate, as is an overall enclosure that has two viewing ports with large exterior baffles, shielding the focal plane from incoming stray light. PHyTIR's electronics is distributed inside and near the vacuum

  3. Optimization of procedure for calibration with radiometer/photometer

    International Nuclear Information System (INIS)

    Detilly, Isabelle

    2009-01-01

    A test procedure for the radiometer/photometer calibrations mark International Light at the Laboratorio de Fotometria y Tecnologia Laser (LAFTA) de la Escuela de Ingenieria Electrica de la Universidad de Costa Rica is established. Two photometric banks are used as experimental set and two calibrations were performed of the International Light. A basic procedure established in the laboratory, is used for calibration from measurements of illuminance and luminous intensity. Some dependent variations of photometric banks used in the calibration process, the programming of the radiometer/photometer and the applied methodology showed the results. The procedure for calibration with radiometer/photometer can be improved by optimizing the programming process of the measurement instrument and possible errors can be minimized by using the recommended procedure. (author) [es

  4. Calibration of the degree of linear polarization measurements of the polarized Sun-sky radiometer based on the POLBOX system.

    Science.gov (United States)

    Li, Zhengqiang; Li, Kaitao; Li, Li; Xu, Hua; Xie, Yisong; Ma, Yan; Li, Donghui; Goloub, Philippe; Yuan, Yinlin; Zheng, Xiaobing

    2018-02-10

    Polarization observation of sky radiation is the frontier approach to improve the remote sensing of atmospheric components, e.g., aerosol and clouds. The polarization calibration of the ground-based Sun-sky radiometer is the basis for obtaining accurate degree of linear polarization (DOLP) measurement. In this paper, a DOLP calibration method based on a laboratory polarized light source (POLBOX) is introduced in detail. Combined with the CE318-DP Sun-sky polarized radiometer, a calibration scheme for DOLP measurement is established for the spectral range of 440-1640 nm. Based on the calibration results of the Sun-sky radiometer observation network, the polarization calibration coefficient and the DOLP calibration residual are analyzed statistically. The results show that the DOLP residual of the calibration scheme is about 0.0012, and thus it can be estimated that the final DOLP calibration accuracy of this method is about 0.005. Finally, it is verified that the accuracy of the calibration results is in accordance with the expected results by comparing the simulated DOLP with the vector radiative transfer calculations.

  5. Design and characterization of the Large-aperture Experiment to Detect the Dark Age (LEDA) radiometer systems

    Science.gov (United States)

    Price, D. C.; Greenhill, L. J.; Fialkov, A.; Bernardi, G.; Garsden, H.; Barsdell, B. R.; Kocz, J.; Anderson, M. M.; Bourke, S. A.; Craig, J.; Dexter, M. R.; Dowell, J.; Eastwood, M. W.; Eftekhari, T.; Ellingson, S. W.; Hallinan, G.; Hartman, J. M.; Kimberk, R.; Lazio, T. Joseph W.; Leiker, S.; MacMahon, D.; Monroe, R.; Schinzel, F.; Taylor, G. B.; Tong, E.; Werthimer, D.; Woody, D. P.

    2018-05-01

    The Large-Aperture Experiment to Detect the Dark Age (LEDA) was designed to detect the predicted O(100) mK sky-averaged absorption of the Cosmic Microwave Background by Hydrogen in the neutral pre- and intergalactic medium just after the cosmological Dark Age. The spectral signature would be associated with emergence of a diffuse Lyα background from starlight during `Cosmic Dawn'. Recently, Bowman et al. (2018) have reported detection of this predicted absorption feature, with an unexpectedly large amplitude of 530 mK, centered at 78 MHz. Verification of this result by an independent experiment, such as LEDA, is pressing. In this paper, we detail design and characterization of the LEDA radiometer systems, and a first-generation pipeline that instantiates a signal path model. Sited at the Owens Valley Radio Observatory Long Wavelength Array, LEDA systems include the station correlator, five well-separated redundant dual polarization radiometers and backend electronics. The radiometers deliver a 30-85 MHz band (16 z < 34) and operate as part of the larger interferometric array, for purposes ultimately of in situ calibration. Here, we report on the LEDA system design, calibration approach, and progress in characterization as of January 2016. The LEDA systems are currently being modified to improve performance near 78 MHz in order to verify the purported absorption feature.

  6. Spectral stratigraphy

    Science.gov (United States)

    Lang, Harold R.

    1991-01-01

    A new approach to stratigraphic analysis is described which uses photogeologic and spectral interpretation of multispectral remote sensing data combined with topographic information to determine the attitude, thickness, and lithology of strata exposed at the surface. The new stratigraphic procedure is illustrated by examples in the literature. The published results demonstrate the potential of spectral stratigraphy for mapping strata, determining dip and strike, measuring and correlating stratigraphic sequences, defining lithofacies, mapping biofacies, and interpreting geological structures.

  7. Spectral reflectance relationships to leaf water stress

    Science.gov (United States)

    Ripple, William J.

    1986-01-01

    Spectral reflectance data were collected from detached snapbean leaves in the laboratory with a multiband radiometer. Four experiments were designed to study the spectral response resulting from changes in leaf cover, relative water content of leaves, and leaf water potential. Spectral regions included in the analysis were red (630-690 nm), NIR (760-900 nm), and mid-IR (2.08-2.35 microns). The red and mid-IR bands showed sensitivity to changes in both leaf cover and relative water content of leaves. The NIR was only highly sensitive to changes in leaf cover. Results provided evidence that mid-IR reflectance was governed primarily by leaf moisture content, although soil reflectance was an important factor when leaf cover was less than 100 percent. High correlations between leaf water potentials and reflectance were attributed to covariances with relative water content of leaves and leaf cover.

  8. Cloud Absorption Radiometer Autonomous Navigation System - CANS

    Science.gov (United States)

    Kahle, Duncan; Gatebe, Charles; McCune, Bill; Hellwig, Dustan

    2013-01-01

    CAR (cloud absorption radiometer) acquires spatial reference data from host aircraft navigation systems. This poses various problems during CAR data reduction, including navigation data format, accuracy of position data, accuracy of airframe inertial data, and navigation data rate. Incorporating its own navigation system, which included GPS (Global Positioning System), roll axis inertia and rates, and three axis acceleration, CANS expedites data reduction and increases the accuracy of the CAR end data product. CANS provides a self-contained navigation system for the CAR, using inertial reference and GPS positional information. The intent of the software application was to correct the sensor with respect to aircraft roll in real time based upon inputs from a precision navigation sensor. In addition, the navigation information (including GPS position), attitude data, and sensor position details are all streamed to a remote system for recording and later analysis. CANS comprises a commercially available inertial navigation system with integral GPS capability (Attitude Heading Reference System AHRS) integrated into the CAR support structure and data system. The unit is attached to the bottom of the tripod support structure. The related GPS antenna is located on the P-3 radome immediately above the CAR. The AHRS unit provides a RS-232 data stream containing global position and inertial attitude and velocity data to the CAR, which is recorded concurrently with the CAR data. This independence from aircraft navigation input provides for position and inertial state data that accounts for very small changes in aircraft attitude and position, sensed at the CAR location as opposed to aircraft state sensors typically installed close to the aircraft center of gravity. More accurate positional data enables quicker CAR data reduction with better resolution. The CANS software operates in two modes: initialization/calibration and operational. In the initialization/calibration mode

  9. GPM GROUND VALIDATION CONICAL SCANNING MILLIMETER-WAVE IMAGING RADIOMETER (COSMIR) MC3E V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Conical Scanning Millimeter-wave Imaging Radiometer (COSMIR) MC3E dataset used the Conical Scanning Millimeter-wave Imaging Radiometer...

  10. GPM GROUND VALIDATION CONICAL SCANNING MILLIMETER-WAVE IMAGING RADIOMETER (COSMIR) GCPEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Conical Scanning Millimeter-wave Imaging Radiometer (COSMIR) GCPEx dataset used the Conical Scanning Millimeter-wave Imaging Radiometer...

  11. HURRICANE AND SEVERE STORM SENTINEL (HS3) HURRICANE IMAGING RADIOMETER (HIRAD) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Hurricane and Severe Storm Sentinel (HS3) Hurricane Imaging Radiometer (HIRAD) was collected by the Hurricane Imaging Radiometer (HIRAD), which was a multi-band...

  12. Assessment of Satellite-Derived Surface Reflectances by NASA's CAR Airborne Radiometer over Railroad Valley, Nevada

    Science.gov (United States)

    Kharbouche, Said; Muller, Jan-Peter; Gatebe, Charles K.; Scanlon, Tracy; Banks, Andrew C.

    2017-01-01

    CAR (Cloud Absorption Radiometer) is a multi-angular and multi-spectral airborne radiometer instrument, whose radiometric and geometric characteristics are well calibrated and adjusted before and after each flight campaign. CAR was built by NASA (National Aeronautics and Space Administration) in 1984. On 16 May 2008, a CAR flight campaign took place over the well-known calibration and validation site of Railroad Valley in Nevada (38.504 deg N, 115.692 deg W).The campaign coincided with the overpasses of several key EO (Earth Observation) satellites such as Landsat-7, Envisat and Terra. Thus, there are nearly simultaneous measurements from these satellites and the CAR airborne sensor over the same calibration site. The CAR spectral bands are close to those of most EO satellites. CAR has the ability to cover the whole range of azimuth view angles and a variety of zenith angles depending on altitude and, as a consequence, the biases seen between satellite and CAR measurements due to both unmatched spectral bands and unmatched angles can be significantly reduced. A comparison is presented here between CARs land surface reflectance (BRF or Bidirectional Reflectance Factor) with those derived from Terra/MODIS (MOD09 and MAIAC), Terra/MISR, Envisat/MERIS and Landsat-7. In this study, we utilized CAR data from low altitude flights (approx. 180 m above the surface) in order to minimize the effects of the atmosphere on these measurements and then obtain a valuable ground-truth data set of surface reflectance. Furthermore, this study shows that differences between measurements caused by surface heterogeneity can be tolerated, thanks to the high homogeneity of the study site on the one hand, and on the other hand, to the spatial sampling and the large number of CAR samples. These results demonstrate that satellite BRF measurements over this site are in good agreement with CAR with variable biases across different spectral bands. This is most likely due to residual aerosol

  13. The design of an in-water optical radiometer

    Digital Repository Service at National Institute of Oceanography (India)

    Desa, E.S.; Desa, B.A; De

    insights into the role playEd. by absorption and scattering processes in the optical properties of water masses. In this paper, we shall describe our design approach to current development effort on a profiling optical radiometer that will measure upwelling...

  14. Calibration of the solar UV radiometers in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Leszczynski, K.; Jokela, K.; Visuri, R.; Ylianttila, L. [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland). Non-Ionizing Radiation Lab.

    1996-12-31

    In this report, the main emphasis is given to (1) the problems associated with the basic calibration of the spectroradiometer and (2) the year-to-year variability of the calibrations of the solar UV network radiometers. Also, the results from intercomparisons of the Brewer and OL 742 spectroradiometers are included

  15. High resolution soil moisture radiometer. [large space structures

    Science.gov (United States)

    Wilheit, T. T.

    1978-01-01

    An electrically scanned pushbroom phased antenna array is described for a microwave radiometer which can provide agriculturally meaningful measurements of soil moisture. The antenna size of 100 meters at 1400 MHz or 230 meters at 611 MHz requires several shuttle launches and orbital assembly. Problems inherent to the size of the structure and specific instrument problems are discussed as well as the preliminary design.

  16. Accurate antenna reflector loss measurements for radiometer calibration budget

    DEFF Research Database (Denmark)

    Skou, Niels

    1996-01-01

    Antenna reflector losses may play an important role in the calibration budget for a microwave radiometer. If the losses are small they are difficult to measure by traditional means. However, they can be assessed directly by radiometric means using the sky brightness temperature as incident...

  17. Measurement of small antenna reflector losses for radiometer calibration budget

    DEFF Research Database (Denmark)

    Skou, Niels

    1997-01-01

    Antenna reflector losses play an important role in the calibration budget for a microwave radiometer. If the losses are small, they are difficult to measure by traditional means. However, they can be assessed directly by radiometric means using the sky brightness temperature as incident radiation...

  18. Combined Radar-Radiometer Surface Soil Moisture and Roughness Estimation

    Science.gov (United States)

    Akbar, Ruzbeh; Cosh, Michael H.; O'Neill, Peggy E.; Entekhabi, Dara; Moghaddam, Mahta

    2017-01-01

    A robust physics-based combined radar-radiometer, or Active-Passive, surface soil moisture and roughness estimation methodology is presented. Soil moisture and roughness retrieval is performed via optimization, i.e., minimization, of a joint objective function which constrains similar resolution radar and radiometer observations simultaneously. A data-driven and noise-dependent regularization term has also been developed to automatically regularize and balance corresponding radar and radiometer contributions to achieve optimal soil moisture retrievals. It is shown that in order to compensate for measurement and observation noise, as well as forward model inaccuracies, in combined radar-radiometer estimation surface roughness can be considered a free parameter. Extensive Monte-Carlo numerical simulations and assessment using field data have been performed to both evaluate the algorithms performance and to demonstrate soil moisture estimation. Unbiased root mean squared errors (RMSE) range from 0.18 to 0.03 cm3cm3 for two different land cover types of corn and soybean. In summary, in the context of soil moisture retrieval, the importance of consistent forward emission and scattering development is discussed and presented.

  19. Improved noise-adding radiometer for microwave receivers

    Science.gov (United States)

    Batelaan, P. D.; Stelzried, C. T.; Goldstein, R. M.

    1973-01-01

    Use of input switch and noise reference standard is avoided by using noise-adding technique. Excess noise from solid state noise-diode is coupled into receiver through directional coupler and square-wave modulated at low rate. High sensitivity receivers for radioastronomy applications are utilized with greater confidence in stability of radiometer.

  20. Calibration OGSE for a multichannel radiometer for Mars atmosphere studies

    Science.gov (United States)

    Jiménez, J. J.; Álvarez, F. J.; Gonzalez-Guerrero, M.; Apéstigue, V.; Martin, I.; Fernández, J. M.; Fernán, A. A.; Arruego, I.

    2017-09-01

    This work describes several OGSEs (Optical Ground Support Equipment) developed by INTA (Spanish Institute of Aerospace Technology - Instituto Nacional de Técnica Aeroespacial) for the calibration and characterization of their self-manufactured multichannel radiometers (Solar Irradiance Sensors - SIS) for planetary atmospheric studies in the frame of some Martian missions at which INTA is participating.

  1. Calibration of the solar UV radiometers in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Leszczynski, K; Jokela, K; Visuri, R; Ylianttila, L [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland). Non-Ionizing Radiation Lab.

    1997-12-31

    In this report, the main emphasis is given to (1) the problems associated with the basic calibration of the spectroradiometer and (2) the year-to-year variability of the calibrations of the solar UV network radiometers. Also, the results from intercomparisons of the Brewer and OL 742 spectroradiometers are included

  2. A New Way to Demonstrate the Radiometer as a Heat Engine

    Science.gov (United States)

    Hladkouski, V. I.; Pinchuk, A. I.

    2015-01-01

    While the radiometer is readily available as a toy, A. E. Woodruff notes that it is also a very useful tool to help us understand how to resolve certain scientific problems. Many physicists think they know how the radiometer works, but only a few actually understand it. Here we present a demonstration that shows that a radiometer can be thought of…

  3. Design of a Push-Broom Multi-Beam Radiometer for Future Ocean Observations

    DEFF Research Database (Denmark)

    Cappellin, C.; Pontoppidan, K.; Nielsen, P. H.

    2015-01-01

    The design of a push-broom multi-beam radiometer for future ocean observations is described. The radiometer provides a sensitivity one order of magnitude higher than a traditional conical scanning radiometer, and has the big advantage of being fully stationary relative to the satellite platform...

  4. Design and Development of the SMAP Microwave Radiometer Electronics

    Science.gov (United States)

    Piepmeier, Jeffrey R.; Medeiros, James J.; Horgan, Kevin A.; Brambora, Clifford K.; Estep, Robert H.

    2014-01-01

    The SMAP microwave radiometer will measure land surface brightness temperature at L-band (1413 MHz) in the presence of radio frequency interference (RFI) for soil moisture remote sensing. The radiometer design was driven by the requirements to incorporate internal calibration, to operate synchronously with the SMAP radar, and to mitigate the deleterious effects of RFI. The system design includes a highly linear super-heterodyne microwave receiver with internal reference loads and noise sources for calibration and an innovative digital signal processor and detection system. The front-end comprises a coaxial cable-based feed network, with a pair of diplexers and a coupled noise source, and radiometer front-end (RFE) box. Internal calibration is provided by reference switches and a common noise source inside the RFE. The RF back-end (RBE) downconverts the 1413 MHz channel to an intermediate frequency (IF) of 120 MHz. The IF signals are then sampled and quantized by high-speed analog-to-digital converters in the radiometer digital electronics (RDE) box. The RBE local oscillator and RDE sampling clocks are phase-locked to a common reference to ensure coherency between the signals. The RDE performs additional filtering, sub-band channelization, cross-correlation for measuring third and fourth Stokes parameters, and detection and integration of the first four raw moments of the signals. These data are packetized and sent to the ground for calibration and further processing. Here we discuss the novel features of the radiometer hardware particularly those influenced by the need to mitigate RFI.

  5. The Potential of Autonomous Ship-Borne Hyperspectral Radiometers for the Validation of Ocean Color Radiometry Data

    Directory of Open Access Journals (Sweden)

    Vittorio E. Brando

    2016-02-01

    Full Text Available Calibration and validation of satellite observations are essential and on-going tasks to ensure compliance with mission accuracy requirements. An automated above water hyperspectral radiometer significantly augmented Australia’s ability to contribute to global and regional ocean color validation and algorithm design activities. The hyperspectral data can be re-sampled for comparison with current and future sensor wavebands. The continuous spectral acquisition along the ship track enables spatial resampling to match satellite footprint. This study reports spectral comparisons of the radiometer data with Visible Infrared Imaging Radiometer Suite (VIIRS and Moderate Resolution Imaging Spectroradiometer (MODIS-Aqua for contrasting water types in tropical waters off northern Australia based on the standard NIR atmospheric correction implemented in SeaDAS. Consistent match-ups are shown for transects of up to 50 km over a range of reflectance values. The MODIS and VIIRS satellite reflectance data consistently underestimated the in situ spectra in the blue with a bias relative to the “dynamic above water radiance and irradiance collector” (DALEC at 443 nm ranging from 9.8 × 10−4 to 3.1 × 10−3 sr−1. Automated acquisition has produced good quality data under standard operating and maintenance procedures. A sensitivity analysis explored the effects of some assumptions in the data reduction methods, indicating the need for a comprehensive investigation and quantification of each source of uncertainty in the estimate of the DALEC reflectances. Deployment on a Research Vessel provides the potential for the radiometric data to be combined with other sampling and observational activities to contribute to algorithm development in the wider bio-optical research community.

  6. Analytically derived conversion of spectral band radiance to brightness temperature

    Energy Technology Data Exchange (ETDEWEB)

    Berk, Alexander [Spectral Sciences, Inc., 44th Avenue, Burlington, MA 01803 (United States)], E-mail: lex@spectral.com

    2008-05-15

    Simple analytic expressions for brightness temperature have been derived in terms of band response function spectral moments. Accuracy measures are also derived. Application of these formulas to GOES-12 Sounder thermal infrared bands produces brightness temperature residuals between -5.0 and 2.5 mK for a 150-400 K temperature range. The magnitude of residuals for the five ASTER Radiometer thermal infrared bands over the same temperature range is less than 0.22 mK.

  7. Flower elliptical constellation of millimeter-wave radiometers for precipitating cloud monitoring at geostationary scale

    Science.gov (United States)

    Marzano, F. S.; Cimini, D.; Montopoli, M.; Rossi, T.; Mortari, D.; di Michele, S.; Bauer, P.

    2009-04-01

    Millimeter-wave observation of the atmospheric parameters is becoming an appealing goal within satellite radiometry applications. The major technological advantage of millimeter-wave (MMW) radiometers is the reduced size of the overall system, for given performances, with respect to microwave sensor. On the other hand, millimeter-wave sounding can exploit window frequencies and various gaseous absorption bands at 50/60 GHz, 118 GHz and 183 GHz. These bands can be used to estimate tropospheric temperature profiles, integrated water vapor and cloud liquid content and, using a differentia spectral mode, light rainfall and snowfall. Millimeter-wave radiometers, for given observation conditions, can also exhibit relatively small field-of-views (FOVs), of the order of some kilometers for low-Earth-orbit (LEO) satellites. However, the temporal resolution of LEO millimeter-wave system observations remains a major drawback with respect to the geostationary-Earth-orbit (GEO) satellites. An overpass every about 12 hours for a single LEO platform (conditioned to a sufficiently large swath of the scanning MMW radiometer) is usually too much when compared with the typical temporal scale variation of atmospheric fields. This feature cannot be improved by resorting to GEO platforms due to their high orbit altitude and consequent degradation of the MMW-sensor FOVs. A way to tackle this impasse is to draw our attention at the regional scale and to focus non-circular orbits over the area of interest, exploiting the concept of micro-satellite flower constellations. The Flower Constellations (FCs) is a general class of elliptical orbits which can be optimized, through genetic algorithms, in order to maximize the revisiting time and the orbital height, ensuring also a repeating ground-track. The constellation concept nicely matches the choice of mini-satellites as a baseline choice, due to their small size, weight (less than 500 kilograms) and relatively low cost (essential when

  8. HybridSpectral Radiometer Systems to Support Ocean Color Cal/Val, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA has an ongoing commitment to collect in situ data with a documented uncertainty in keeping with established performance metrics for vicarious calibration of...

  9. Upgraded ECE radiometer on the Tore Supra Tokamak

    International Nuclear Information System (INIS)

    Segui, J.L.; Molina, D.; Goniche, M.; Maget, P.; Udintsev, V.S.; Kraemer-Flecken, A.

    2004-01-01

    An upgraded 32-channel heterodyne radiometer, 1 GHz spaced, is used on the Tore-Supra tokamak to measure the electron cyclotron emission (ECE) in the frequency range 78-110 GHz for the ordinary mode (O1) and 94-126.5 GHz for the extraordinary mode (X2). From now radial resolution is essentially limited by ECE relativistic effects related to electron temperature and density, not by the channels frequency spacing. For example, this leads to precise electron temperature mapping during magneto hydrodynamic activities (MHD). In the equatorial plane, we use a dual polarisation Gaussian optics lens antenna. It has low spreading and a perpendicular line-of-sight that gives ECE measurements very low refraction and Doppler effects. Assuming that the plasma is a black body and there is no overlap between ECE harmonics, one can deduce the electron temperature profile by using the first harmonic ordinary mode (O1) or the second harmonic extraordinary mode (X2). The principle radio frequency emitter (RF) has its frequencies down shifted into intermediary frequencies (IF) that span from 2 to 18 GHz in the single side band mode (SSB). It is amplified by low noise IF amplifiers before forming channels. A separate O/X mode RF front-end allows the use of an IF electronic mode selector. This gives the potentiality of simultaneous O/X mode measurements in the 94-110 GHz. RF and IF filters reject the gyrotron frequency (118 GHz) in order to perform electron temperature measurements during electron cyclotron resonance heated plasmas. A precise absolute spectral calibration is performed outside the tokamak vacuum vessel by using a 600 deg C black body hot source, a double coherent digital signal averaging (trigger, turn and clock) on the waveform generated by a mechanical chopper, and a simulated tokamak window. The use of differential electronics and strong electromagnetic shielding improves also the calibration precision. The fast and slow data acquisition systems are free of aliasing

  10. Upgraded ECE radiometer on the Tore Supra Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Segui, J.L.; Molina, D.; Goniche, M.; Maget, P.; Udintsev, V.S. [Association Euratom-CEA, Centre d' Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Antar, G.Y. [Center for Energy Research, UCSD, La Jolla CA (United States); Kraemer-Flecken, A. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Plasmaphysik

    2004-07-01

    An upgraded 32-channel heterodyne radiometer, 1 GHz spaced, is used on the Tore-Supra tokamak to measure the electron cyclotron emission (ECE) in the frequency range 78-110 GHz for the ordinary mode (O1) and 94-126.5 GHz for the extraordinary mode (X2). From now radial resolution is essentially limited by ECE relativistic effects related to electron temperature and density, not by the channels frequency spacing. For example, this leads to precise electron temperature mapping during magneto hydrodynamic activities (MHD). In the equatorial plane, we use a dual polarisation Gaussian optics lens antenna. It has low spreading and a perpendicular line-of-sight that gives ECE measurements very low refraction and Doppler effects. Assuming that the plasma is a black body and there is no overlap between ECE harmonics, one can deduce the electron temperature profile by using the first harmonic ordinary mode (O1) or the second harmonic extraordinary mode (X2). The principle radio frequency emitter (RF) has its frequencies down shifted into intermediary frequencies (IF) that span from 2 to 18 GHz in the single side band mode (SSB). It is amplified by low noise IF amplifiers before forming channels. A separate O/X mode RF front-end allows the use of an IF electronic mode selector. This gives the potentiality of simultaneous O/X mode measurements in the 94-110 GHz. RF and IF filters reject the gyrotron frequency (118 GHz) in order to perform electron temperature measurements during electron cyclotron resonance heated plasmas. A precise absolute spectral calibration is performed outside the tokamak vacuum vessel by using a 600 deg C black body hot source, a double coherent digital signal averaging (trigger, turn and clock) on the waveform generated by a mechanical chopper, and a simulated tokamak window. The use of differential electronics and strong electromagnetic shielding improves also the calibration precision. The fast and slow data acquisition systems are free of aliasing

  11. Precipitation from the GPM Microwave Imager and Constellation Radiometers

    Science.gov (United States)

    Kummerow, Christian; Randel, David; Kirstetter, Pierre-Emmanuel; Kulie, Mark; Wang, Nai-Yu

    2014-05-01

    Satellite precipitation retrievals from microwave sensors are fundamentally underconstrained requiring either implicit or explicit a-priori information to constrain solutions. The radiometer algorithm designed for the GPM core and constellation satellites makes this a-priori information explicit in the form of a database of possible rain structures from the GPM core satellite and a Bayesian retrieval scheme. The a-priori database will eventually come from the GPM core satellite's combined radar/radiometer retrieval algorithm. That product is physically constrained to ensure radiometric consistency between the radars and radiometers and is thus ideally suited to create the a-priori databases for all radiometers in the GPM constellation. Until a robust product exists, however, the a-priori databases are being generated from the combination of existing sources over land and oceans. Over oceans, the Day-1 GPM radiometer algorithm uses the TRMM PR/TMI physically derived hydrometer profiles that are available from the tropics through sea surface temperatures of approximately 285K. For colder sea surface temperatures, the existing profiles are used with lower hydrometeor layers removed to correspond to colder conditions. While not ideal, the results appear to be reasonable placeholders until the full GPM database can be constructed. It is more difficult to construct physically consistent profiles over land due to ambiguities in surface emissivities as well as details of the ice scattering that dominates brightness temperature signatures over land. Over land, the a-priori databases have therefore been constructed by matching satellite overpasses to surface radar data derived from the WSR-88 network over the continental United States through the National Mosaic and Multi-Sensor QPE (NMQ) initiative. Databases are generated as a function of land type (4 categories of increasing vegetation cover as well as 4 categories of increasing snow depth), land surface temperature and

  12. Narrow Field of View Zenith Radiometer (NFOV) Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, C; Marshak, A; Hodges, G; Barnard, JC; Schmelzer, J

    2008-11-01

    The two-channel narrow field-of-view radiometer (NFOV2) is a ground-based radiometer that looks straight up and measures radiance directly above the instrument at wavelengths of 673 and 870 nm. The field-of-view of the instrument is 1.2 degrees, and the sampling time resolution is one second. Measurements of the NFOV2 have been used to retrieve optical properties for overhead clouds that range from patchy to overcast. With a one-second sampling rate of the NFOV2, faster than almost any other ARM Climate Research Facility (ACRF) instrument, we are able, for the first time, to capture changes in cloud optical properties at the natural time scale of cloud evolution.

  13. Effect of a spacer moiety on radiometal labelled Neurotensin derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Mascarin, A.; Valverde, I.E.; Mindt, T.L. [Univ. of Basel Hospital (Switzerland). Div. of Radiopharmaceutical Chemistry

    2013-07-01

    The binding sequence of the regulatory peptide Neurotensin, NT(8-13), represents a promising tumour-specific vector for the development of radiopeptides useful in nuclear oncology for the diagnosis (imaging) and therapy of cancer. A number of radiometal-labelled NT(8-13) derivatives have been reported, however, the effect of the spacer which connects the vector with the radiometal complex has yet not been investigated systematically. Because a spacer moiety can influence potentially important biological characteristics of radiopeptides, we synthesized three [DOTA({sup 177}Lu)]-X-NT(8-13) derivatives and evaluated the effect of a spacer (X) on the physico-chemical properties of the conjugate including lipophilicity, stability, and in vitro receptor affinity and cell internalization. (orig.)

  14. The Along Track Scanning Radiometer (ATSR) for ERS1

    Science.gov (United States)

    Delderfield, J.; Llewellyn-Jones, D. T.; Bernard, R.; de Javel, Y.; Williamson, E. J.

    1986-01-01

    The ATSR is an infrared imaging radiometer which has been selected to fly aboard the ESA Remote Sensing Satellite No. 1 (ERS1) with the specific objective of accurately determining global Sea Surface Temperature (SST). Novel features, including the technique of 'along track' scanning, a closed Stirling cycle cooler, and the precision on-board blackbodies are described. Instrument subsystems are identified and their design trade-offs discussed.

  15. Optimum Image Formation for Spaceborne Microwave Radiometer Products.

    Science.gov (United States)

    Long, David G; Brodzik, Mary J

    2016-05-01

    This paper considers some of the issues of radiometer brightness image formation and reconstruction for use in the NASA-sponsored Calibrated Passive Microwave Daily Equal-Area Scalable Earth Grid 2.0 Brightness Temperature Earth System Data Record project, which generates a multisensor multidecadal time series of high-resolution radiometer products designed to support climate studies. Two primary reconstruction algorithms are considered: the Backus-Gilbert approach and the radiometer form of the scatterometer image reconstruction (SIR) algorithm. These are compared with the conventional drop-in-the-bucket (DIB) gridded image formation approach. Tradeoff study results for the various algorithm options are presented to select optimum values for the grid resolution, the number of SIR iterations, and the BG gamma parameter. We find that although both approaches are effective in improving the spatial resolution of the surface brightness temperature estimates compared to DIB, SIR requires significantly less computation. The sensitivity of the reconstruction to the accuracy of the measurement spatial response function (MRF) is explored. The partial reconstruction of the methods can tolerate errors in the description of the sensor measurement response function, which simplifies the processing of historic sensor data for which the MRF is not known as well as modern sensors. Simulation tradeoff results are confirmed using actual data.

  16. A new real time infrared background discrimination radiometer (BDR)

    International Nuclear Information System (INIS)

    Kopolovich, Z.; Cabib, D.; Buckwald, R.A.

    1989-01-01

    This paper reports on a new radiometer (BDR) that has been developed, which discriminates small differences between an object and its surrounding background, and is able to measure an object's changing contrast when the contrast of a moving object is to be measured against a changing background. The difference in radiant emittance of a small object against its background or of two objects with respect to each other and this difference is small compared to the emittance itself. Practical examples of such measurements are contrast measurements of airplanes and missiles in flight, contrast measurements of small, weak objects on a warm background and uniformity measurements of radiant emittance from an object's surface. Previous instruments were unable to make such measurements since the process of contrast measurement with a fixed field of view radiometer is too slow for implementation on flying objects; detection of a small difference between two large DC signals is impossible in a traditional fixed field of view radiometer when the instrument itself is saturated

  17. A horizontal vane radiometer: Experiment, theory, and simulation

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, David; Larraza, Andres, E-mail: larraza@nps.edu [Department of Physics, Naval Postgraduate School, Monterey, California 93940 (United States); Garcia, Alejandro [Department of Physics and Astronomy, San Jose State University, San Jose, California 95152 (United States)

    2016-03-15

    The existence of two motive forces on a Crookes radiometer has complicated the investigation of either force independently. The thermal creep shear force in particular has been subject to differing interpretations of the direction in which it acts and its order of magnitude. In this article, we provide a horizontal vane radiometer design which isolates the thermal creep shear force. The horizontal vane radiometer is explored through experiment, kinetic theory, and the Direct Simulation Monte Carlo (DSMC) method. The qualitative agreement between the three methods of investigation is good except for a dependence of the force on the width of the vane even when the temperature gradient is narrower than the vane which is present in the DSMC method results but not in the theory. The experimental results qualitatively resemble the theory in this regard. The quantitative agreement between the three methods of investigation is better than an order of magnitude in the cases examined. The theory is closer to the experimental values for narrow vanes and the simulations are closer to the experimental values for the wide vanes. We find that the thermal creep force acts from the hot side to the cold side of the vane. We also find the peak in the radiometer’s angular speed as a function of pressure is explained as much by the behavior of the drag force as by the behavior of the thermal creep force.

  18. A horizontal vane radiometer: Experiment, theory, and simulation

    International Nuclear Information System (INIS)

    Wolfe, David; Larraza, Andres; Garcia, Alejandro

    2016-01-01

    The existence of two motive forces on a Crookes radiometer has complicated the investigation of either force independently. The thermal creep shear force in particular has been subject to differing interpretations of the direction in which it acts and its order of magnitude. In this article, we provide a horizontal vane radiometer design which isolates the thermal creep shear force. The horizontal vane radiometer is explored through experiment, kinetic theory, and the Direct Simulation Monte Carlo (DSMC) method. The qualitative agreement between the three methods of investigation is good except for a dependence of the force on the width of the vane even when the temperature gradient is narrower than the vane which is present in the DSMC method results but not in the theory. The experimental results qualitatively resemble the theory in this regard. The quantitative agreement between the three methods of investigation is better than an order of magnitude in the cases examined. The theory is closer to the experimental values for narrow vanes and the simulations are closer to the experimental values for the wide vanes. We find that the thermal creep force acts from the hot side to the cold side of the vane. We also find the peak in the radiometer’s angular speed as a function of pressure is explained as much by the behavior of the drag force as by the behavior of the thermal creep force.

  19. Manual of program operation for data analysis from radiometer system

    International Nuclear Information System (INIS)

    Silva Mello, L.A.R. da; Migliora, C.G.S.

    1987-12-01

    This manual describes how to use the software to retrieve and analyse data from radiometer systems and raingauges used in the 12 GHz PROPAGATION MEASUREMENTS/CANADA - TELEBRAS COOPERATION PROGRAM. The data retrieval and analisys is being carried out by CETUC, as part of the activities of the project Simulacao de Enlaces Satelite (SES). The software for these tasks has been supplied by the Canadian Research Centre (CRC), together with the measurement equipment. The two following sections describe the use of the data retrieval routines and the data analysis routines of program ATTEN. Also, a quick reference guide for commands that can be used when a microcomputer is local or remotely connected to a radiometer indoor unit is included as a last section. A more detailed description of these commands, their objectives and cautions that should de taken when using them can be found in the manual ''12 GHz Propagation Measurements System - Volume 1 - Dual Slope Radiometer and Data Aquisition System'', supplied by Diversitel Communications Inc. (author) [pt

  20. Source analysis of spaceborne microwave radiometer interference over land

    Science.gov (United States)

    Guan, Li; Zhang, Sibo

    2016-03-01

    Satellite microwave thermal emissions mixed with signals from active sensors are referred to as radiofrequency interference (RFI). Based on Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) observations from June 1 to 16, 2011, RFI over Europe was identified and analyzed using the modified principal component analysis algorithm in this paper. The X band AMSR-E measurements in England and Italy are mostly affected by the stable, persistent, active microwave transmitters on the surface, while the RFI source of other European countries is the interference of the reflected geostationary TV satellite downlink signals to the measurements of spaceborne microwave radiometers. The locations and intensities of the RFI induced by the geostationary TV and communication satellites changed with time within the observed period. The observations of spaceborne microwave radiometers in ascending portions of orbits are usually interfered with over European land, while no RFI was detected in descending passes. The RFI locations and intensities from the reflection of downlink radiation are highly dependent upon the relative geometry between the geostationary satellite and the measuring passive sensor. Only these fields of view of a spaceborne instrument whose scan azimuths are close to the azimuth relative to the geostationary satellite are likely to be affected by RFI.

  1. The multi-filter rotating shadowband radiometer (MFRSR) - precision infrared radiometer (PIR) platform in Fairbanks: Scientific objectives

    Energy Technology Data Exchange (ETDEWEB)

    Stamnes, K.; Leontieva, E. [Univ. of Alaska, Fairbanks (United States)

    1996-04-01

    The multi-filter rotating shadowband radiometer (MFRSR) and precision infrared radiometer (PIR) have been employed at the Geophysical Institute in Fairbanks to check their performance under arctic conditions. Drawing on the experience of the previous measurements in the Arctic, the PIR was equipped with a ventilator to prevent frost and moisture build-up. We adopted the Solar Infrared Observing Sytem (SIROS) concept from the Southern Great Plains Cloud and Radiation Testbed (CART) to allow implementation of the same data processing software for a set of radiation and meteorological instruments. To validate the level of performance of the whole SIROS prior to its incorporation into the North Slope of Alaska (NSA) Cloud and Radiation Testbed Site instrumental suite for flux radiatin measurements, the comparison between measurements and model predictions will be undertaken to assess the MFRSR-PIR Arctic data quality.

  2. Spectral analysis of the Forel-Ule Ocean colour comparator scale

    Science.gov (United States)

    Wernand, M. R.; van der Woerd, H. J.

    2010-04-01

    François Alphonse Forel (1890) and Willi Ule (1892) composed a colour comparator scale, with tints varying from indigo-blue to coca-cola brown, to quantify the colour of natural waters, like seas, lakes and rivers. For each measurement, the observer compares the colour of the water above a submersed white disc (Secchi disc) with the hand-held scale of pre-defined colours. The scale can be well reproduced from a simple recipe for twenty-one coloured chemical solutions and because the ease of its use, the Forel-Ule (FU) scale has been applied globally and intensively by oceanographers and limnologists from the year 1890. Indeed, the archived FU data belong to the oldest oceanographic data sets and do contain information on the changes in geobiophysical properties of natural waters during the last century. In this article we describe the optical properties of the FU-scale and its ability to cover the colours of natural waters, as observed by the human eye. The recipe of the scale and its reproduction is described. The spectral transmission of the tubes, with belonging chromaticity coordinates, is presented. The FU scale, in all its simplicity, is found to be an adequate ocean colour comparator scale. The scale is well characterized, is stable and observations are reproducible. This supports the idea that the large historic data base of FU measurements is coherent and well calibrated. Moreover, the scale can be coupled to contemporary multi-spectral observations with hand-held and satellite-based spectrometers.

  3. Boreal Inundation Mapping with SMAP Radiometer Data for Methane Studies

    Science.gov (United States)

    Kim, Seungbum; Brisco, Brian; Poncos, Valentin

    2017-04-01

    Inundation and consequent anoxic condition induce methane release, which is one of the most potent greenhouse gases. Boreal regions contain large amounts of organic carbon, which is a potentially major methane emission source under climatic warming conditions. Boreal wetlands in particular are one of the largest sources of uncertainties in global methane budget. Wetland spatial extent together with the gas release rate remains highly unknown. Characterization of the existing inundation database is poor, because of the inundation under clouds and dense vegetation. In this work, the inundation extent is derived using brightness temperature data acquired by the L-band Soil Moisture Active Passive (SMAP) satellite, which offers the L-band capabilities to penetrate clouds and vegetation at 3-day revisit. The fidelity of the SMAP watermask is assessed as a first step in this investigation by comparing with the following data sets: 3-m resolution maps derived using Radarsat synthetic aperture radar (SAR) data in northern Canada and multi-sensor climatology over Siberia. Because Radarsat coverages are limited despite its high spatial resolution, at the time and location where Radarsats are not available, we also compare with 3-km resolution SMAP SAR data that are concurrent with the SMAP radiometer data globally until July 2015. Inundation extents were derived with Radarsat, SMAP SAR, and SMAP radiometer over the 60 km x 60km area at Peace Athabasca Delta (PAD), Canada on 6 days in spring and summer 2015. The SMAP SAR results match the locations of Radarsat waterbodies. However, the SMAP SAR underestimates the water extent, mainly over mixed pixels that have subpixel land presence. The threshold value (-3 dB) applied to the SMAP SAR was determined previously over the global domain. The threshold is dependent on the type of local landcover within a mixed pixel. Further analysis is needed to locally optimize the threshold. The SMAP radiometer water fraction over Peace

  4. Radiometer Calibration and Characterization (RCC) User's Manual: Windows Version 4.0

    Energy Technology Data Exchange (ETDEWEB)

    Andreas, Afshin M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wilcox, Stephen M. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-02-29

    The Radiometer Calibration and Characterization (RCC) software is a data acquisition and data archival system for performing Broadband Outdoor Radiometer Calibrations (BORCAL). RCC provides a unique method of calibrating broadband atmospheric longwave and solar shortwave radiometers using techniques that reduce measurement uncertainty and better characterize a radiometer's response profile. The RCC software automatically monitors and controls many of the components that contribute to uncertainty in an instrument's responsivity. This is a user's manual and guide to the RCC software.

  5. Application of microwave radiometers for wetlands and estuaries monitoring

    International Nuclear Information System (INIS)

    Shutko, A.; Haldin, A.; Novichikhin, E.

    1997-01-01

    This paper presents the examples of experimental data obtained with airborne microwave radiometers used for monitoring of wetlands and estuaries located in coastal environments. The international team of researchers has successfully worked in Russia, Ukraine and USA. The data presented relate to a period of time between 1990 and 1995. They have been collected in Odessa Region, Black Sea coast, Ukraine, in Regions of Pittsville and Winfield, Maryland, USA, and in Region of St. Marks, Florida, USA. The parameters discussed are a soil moisture, depth to a shallow water table, vegetation index, salinity of water surface

  6. A brief history of 25 years (or more) of infrared imaging radiometers

    Science.gov (United States)

    Lyon, Bernard R., Jr.; Orlove, Gary L.

    2003-04-01

    Modern thermal imaging radiometers are infrared systems usually endowed with some means of making surface temperature measurements of objects, as well as providing an image. These devices have evolved considerably over the past few decades, and are continuing to do so at an accelerating rate. Changes are not confined to merely camera size and user interface, but also include critical parameters, such as sensitivity, accuracy, dynamic range, spectral response, capture rates, storage media, and numerous other features, options, and accessories. Familiarity with this changing technology is much more than an academic topic. A misunderstanding or false assumption concerning system differences, could lead to misinterpretation of data, inaccurate temperature measurements, or disappointing, ambiguous results. Marketing demands have had considerable influence in the design and operation of these systems. In the past, many thermographers were scientists, engineers and researchers. Today, however, the majorities of people using these instruments work in the industrial sector and are involved in highly technical skilled trades. This change of operating personnel has effectively changed the status of these devices from a 'scientific instrument', to an 'essential tool'. Manufacturers have recognized this trend and responded accordingly, as seen in their product designs. This paper explores the history of commercial infrared imaging systems and accessories. Emphasis is placed on, but not confined to, real time systems with video output, capable of temperature measurements.

  7. Spectro-radiometers ASTER and MODIS - character of data, their accessibility and exploitability in area of environment

    International Nuclear Information System (INIS)

    Hlasny, T.; Bucha, T.; Rasi, R.

    2005-01-01

    In this presentation some basic information about spectro-radiometers ASTER and MODIS are presented. Relative wide opportunities of exploitation of these products in area of environment, their high spectral and in case of MODIS time resolution are discussed. These parameters create starting-point for building-up of regional monitoring systems of different biophysical characteristics of terrestrial ecosystems and monitoring of time and spatial variability. Next effort in this area should be aimed on development and optimisation of regional models based on monitoring of time and spatial changes of vegetable and foliar indexes (NDVI, EVI, LAI), photosynthetically active part of radiation absorbed by vegetation (FPAR) and likewise, as well as detail analyses of these data in context of global climatic changes. Perspectives of remote sensing earth in the Slovak republic are discussed

  8. Validation of ocean color sensors using a profiling hyperspectral radiometer

    Science.gov (United States)

    Ondrusek, M. E.; Stengel, E.; Rella, M. A.; Goode, W.; Ladner, S.; Feinholz, M.

    2014-05-01

    Validation measurements of satellite ocean color sensors require in situ measurements that are accurate, repeatable and traceable enough to distinguish variability between in situ measurements and variability in the signal being observed on orbit. The utility of using a Satlantic Profiler II equipped with HyperOCR radiometers (Hyperpro) for validating ocean color sensors is tested by assessing the stability of the calibration coefficients and by comparing Hyperpro in situ measurements to other instruments and between different Hyperpros in a variety of water types. Calibration and characterization of the NOAA Satlantic Hyperpro instrument is described and concurrent measurements of water-leaving radiances conducted during cruises are presented between this profiling instrument and other profiling, above-water and moored instruments. The moored optical instruments are the US operated Marine Optical BuoY (MOBY) and the French operated Boussole Buoy. In addition, Satlantic processing versions are described in terms of accuracy and consistency. A new multi-cast approach is compared to the most commonly used single cast method. Analysis comparisons are conducted in turbid and blue water conditions. Examples of validation matchups with VIIRS ocean color data are presented. With careful data collection and analysis, the Satlantic Hyperpro profiling radiometer has proven to be a reliable and consistent tool for satellite ocean color validation.

  9. Four-channel temperature and humidity microwave scanning radiometer

    Science.gov (United States)

    Xu, Pei-Yuan

    1994-06-01

    A compact four-channel microwave scanning radiometer for tropospheric remote sensing is being developed. A pair of 53.85 and 56.02 GHz and a pair of 23.87 and 31.65 GHz are adopted as temperature and humidity channels' frequencies respectively. For each pair of frequencies it has an offset reflector antenna and a Dicke-switching receiver. The pair of receivers is assembled in an enclosure, which is mounted on the rotating table of an azimuth mounting and the pair of antennas is connected with the rotating table of an azimuth mounting in the opposite side by a pair of elevation arms. Each antenna is composed of a 90 degree off-set paraboloid and a conical corrugated horn. Each antenna patterrn of four channels has nearly same HPBW, low side lobes, and low VSWR. The dual band humidity receiver is a time sharing type with 0.2K sensitivity at 1-sec integration time. The dual band temperature receiver is a band sharing type with 0.2K sensitivity at 10-sec integration time. The radiometer and observation are controlled by a single chip microcomputer to realize the unattended operation.

  10. Infrared fibers for radiometer thermometry in hypothermia and hyperthermia treatment

    International Nuclear Information System (INIS)

    Katzir, A.; Bowman, H.F.; Asfour, Y.; Zur, A.; Valeri, C.R.

    1989-01-01

    Hypothermia is a condition which results from prolonged exposure to a cold environment. Rapid and efficient heating is needed to rewarm the patient from 32-35 degrees C to normal body temperature. Hyperthermia in cancer treatment involves heating malignant tumors to 42.5-43.0 degrees C for an extended period (e.g., 30 min) in an attempt to obtain remission. Microwave or radio frequency heating is often used for rewarming in hypothermia or for temperature elevation in hyperthermia treatment. One severe problem with such heating is the accurate measurement and control of temperature in the presence of a strong electromagnetic field. For this purpose, we have developed a fiberoptic radiometer system which is based on a nonmetallic, infrared fiber probe, which can operate either in contact or noncontact mode. In preliminary investigations, the radiometer worked well in a strong microwave or radiofrequency field, with an accuracy of +/- 0.5 degrees C. This fiberoptic thermometer was used to control the surface temperature of objects within +/- 2 degrees C

  11. Field measurements of the global UV-B radiation: a comparison between a broad-band radiometer and a Brewer spectrophotometer

    International Nuclear Information System (INIS)

    Anav, A.; Moriconi, M.L.; Di Menno, M.; Giannoccolo, S.

    1996-01-01

    The spectral responsivity shape plays an important role in the prospect of a wide use of broad-band meters in the UV-B monitoring. As most UV-B broad-band meters have a responsivity approximating an erythemal action spectrum, a measurement campaign was planned to verify if such an instrument could be successfully used to measure the unfiltered global irradiance. A Yankee radiometer mod. UV-B 1 and a Brewer spectrophotometer, considered as a reference meter, were compared for this purpose. A short theoretical treatment of the Yankee radiometer response and some results of the comparison are shown. Only clear-sky days data are selected so that the UV-B radiation reaching the ground could be modelled as the sum of the direct and isotropic diffuse components. The comparison results show a good agreement between the two instruments and confirm the capability of a broad-band UV-B radiometer of correctly measuring the global irradiance

  12. Relationship of red and photographic infrared spectral radiances to alfalfa biomass, forage water content, percentage canopy cover, and severity of drought stress

    Science.gov (United States)

    Tucker, C. J.; Elgin, J. H., Jr.; Mcmurtrey, J. E., III

    1979-01-01

    Red and photographic infrared spectral data were collected using a handheld radiometer for two cuttings of alfalfa. Significant linear and non-linear correlation coefficients were found between the spectral variables and plant height, biomass, forage water content, and estimated canopy cover for the earlier alfalfa cutting. The alfalfa of later cutting experienced a period of severe drought stress which limited growth. The spectral variables were found to be highly correlated with the estimated drought scores for this alfalfa cutting.

  13. Validation of the uncertainty budget for soft X-ray radiant power measurement using a cryogenic radiometer

    International Nuclear Information System (INIS)

    Rabus, H.; Klein, R.; Scholze, F.; Thornagel, R.; Ulm, G.

    2002-01-01

    The cryogenic radiometer SYRES, a thermal detector based on the electrical substitution principle, has been used as the primary detector standard for radiant power measurement in the ultraviolet, vacuum ultraviolet and soft X-ray spectral ranges. In order to investigate the possibility of radiant energy being deposited in its absorber cavity without being transformed into heat when detecting soft X-rays, SYRES has been directly compared with the electron storage ring BESSY 1, a primary radiometric source standard of calculable spectral radiant power. To this end, the integral radiant power emitted by the storage ring,into a solid angle defined by a high-precision aperture was measured with SYRES. The experiments were conducted at two nominal energies of the circulating electrons, 800 MeV and 340 MeV, to study the influence of the different spectral distributions of the synchrotron radiation. For the original graphite-coated cavity absorber, significant discrepancies were found which could be traced back to the ablation of the graphite coating from the copper cavity body. In the case of the new gold-coated cavity absorber, the calculated and measured values of the radiant power agreed in all experiments within the combined relative uncertainties of typically 2.5 x 10 -3 (k = 1). (author)

  14. Validation of the uncertainty budget for soft X-ray radiant power measurement using a cryogenic radiometer

    CERN Document Server

    Rabus, H; Scholze, F; Thornagel, R; Ulm, G

    2002-01-01

    The cryogenic radiometer SYRES, a thermal detector based on the electrical substitution principle, has been used as the primary detector standard for radiant power measurement in the ultraviolet, vacuum ultraviolet and soft X-ray spectral ranges. In order to investigate the possibility of radiant energy being deposited in its absorber cavity without being transformed into heat when detecting soft X-rays, SYRES has been directly compared with the electron storage ring BESSY 1, a primary radiometric source standard of calculable spectral radiant power. To this end, the integral radiant power emitted by the storage ring,into a solid angle defined by a high-precision aperture was measured with SYRES. The experiments were conducted at two nominal energies of the circulating electrons, 800 MeV and 340 MeV, to study the influence of the different spectral distributions of the synchrotron radiation. For the original graphite-coated cavity absorber, significant discrepancies were found which could be traced back to th...

  15. Physical, biological, and chemical data from radiometer, profiling reflectance radiometer, and CTD casts in a world-wide distribution as part of the SeaWiFS/SIMBIOS project from 13 September 1981 to 16 December 1999 (NODC Accession 0000632)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical, biological, and chemical data were collected using radiometer, profiling reflectance radiometer, and CTD casts in a world-wide distribution from 13...

  16. Compact Front-end Prototype for Next Generation RFI-rejecting Polarimetric L-band Radiometer

    DEFF Research Database (Denmark)

    Jensen, Brian Sveistrup; Søbjærg, Sten Schmidl; Skou, Niels

    2009-01-01

    Realizing the need for lower noise figure and smaller physical size in todays higly sensitive radiometers, this paper presents a new compact analog front-end (AFE) for use with the existing L-band (1400-1427 MHz) radiometer designed and operated by the Technical University of Denmark. Using subha...

  17. A simple method to minimize orientation effects in a profiling radiometer

    Digital Repository Service at National Institute of Oceanography (India)

    Suresh, T.; Talaulikar, M.; Desa, E.; Matondkar, S.G.P.; SrinivasaKumar, T.; Lotlikar, A.

    -fall radiometer is found to be a better option for measuring underwater light parameters as it avoids the effects of ship shadow and is easy to operate, the measurements demand profiling the radiometer vertical in water with minimum tilt. Here we present...

  18. Challenges in application of Active Cold Loads for microwave radiometer calibration

    DEFF Research Database (Denmark)

    Søbjærg, Sten Schmidl; Balling, Jan E.; Skou, Niels

    2012-01-01

    Two Active Cold Loads (ACLs) for microwave radiometer calibration, operating at X-band, are evaluated with respect to important stability parameters. Using a stable radiometer system as test bed, absolute levels of 77 K and 55 K are found. This paper identifies and summarizes potential challenges...

  19. Spaceborne L-band Radiometers: Push-broom or Synthetic Aperture?

    DEFF Research Database (Denmark)

    Skou, Niels

    2004-01-01

    L-band radiometers can measure ocean salinity and soil moisture from space. A synthetic aperture radiometer system, SMOS, is under development by ESA for launch in 2007. A real aperture push-broom system, Aquarius, has been approved by NASA for launch in 2008. Pros et cons of the two fundamentally...

  20. Evaluation of the new ESR network software for the retrieval of direct sun products from CIMEL CE318 and PREDE POM01 sun-sky radiometers

    Directory of Open Access Journals (Sweden)

    V. Estellés

    2012-12-01

    Full Text Available The European Skynet Radiometers network (EuroSkyRad or ESR has been recently established as a research network of European PREDE sun-sky radiometers. Moreover, ESR is federated with SKYNET, an international network of PREDE sun-sky radiometers mostly present in East Asia. In contrast to SKYNET, the European network also integrates users of the CIMEL CE318 sky–sun photometer. Keeping instrumental duality in mind, a set of open source algorithms has been developed consisting of two modules for (1 the retrieval of direct sun products (aerosol optical depth, wavelength exponent and water vapor from the sun extinction measurements; and (2 the inversion of the sky radiance to derive other aerosol optical properties such as size distribution, single scattering albedo or refractive index. In this study we evaluate the ESR direct sun products in comparison with the AERosol RObotic NETwork (AERONET products. Specifically, we have applied the ESR algorithm to a CIMEL CE318 and PREDE POM simultaneously for a 4-yr database measured at the Burjassot site (Valencia, Spain, and compared the resultant products with the AERONET direct sun measurements obtained with the same CIMEL CE318 sky–sun photometer. The comparison shows that aerosol optical depth differences are mostly within the nominal uncertainty of 0.003 for a standard calibration instrument, and fall within the nominal AERONET uncertainty of 0.01–0.02 for a field instrument in the spectral range 340 to 1020 nm. In the cases of the Ångström exponent and the columnar water vapor, the differences are lower than 0.02 and 0.15 cm, respectively. Therefore, we present an open source code program that can be used with both CIMEL and PREDE sky radiometers and whose results are equivalent to AERONET and SKYNET retrievals.

  1. Soil Moisture ActivePassive (SMAP) L-Band Microwave Radiometer Post-Launch Calibration

    Science.gov (United States)

    Peng, Jinzheng; Piepmeier, Jeffrey R.; Misra, Sidharth; Dinnat, Emmanuel P.; Hudson, Derek; Le Vine, David M.; De Amici, Giovanni; Mohammed, Priscilla N.; Yueh, Simon H.; Meissner, Thomas

    2016-01-01

    The SMAP microwave radiometer is a fully-polarimetric L-band radiometer flown on the SMAP satellite in a 6 AM/ 6 PM sun-synchronous orbit at 685 km altitude. Since April, 2015, the radiometer is under calibration and validation to assess the quality of the radiometer L1B data product. Calibration methods including the SMAP L1B TA2TB (from Antenna Temperature (TA) to the Earth’s surface Brightness Temperature (TB)) algorithm and TA forward models are outlined, and validation approaches to calibration stability/quality are described in this paper including future work. Results show that the current radiometer L1B data satisfies its requirements.

  2. Spectral Imaging by Upconversion

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin; Pedersen, Christian; Tidemand-Lichtenberg, Peter

    2011-01-01

    We present a method to obtain spectrally resolved images using upconversion. By this method an image is spectrally shifted from one spectral region to another wavelength. Since the process is spectrally sensitive it allows for a tailored spectral response. We believe this will allow standard...... silicon based cameras designed for visible/near infrared radiation to be used for spectral images in the mid infrared. This can lead to much lower costs for such imaging devices, and a better performance....

  3. Spectral classifying base on color of live corals and dead corals covered with algae

    Science.gov (United States)

    Nurdin, Nurjannah; Komatsu, Teruhisa; Barille, Laurent; Akbar, A. S. M.; Sawayama, Shuhei; Fitrah, Muh. Nur; Prasyad, Hermansyah

    2016-05-01

    Pigments in the host tissues of corals can make a significant contribution to their spectral signature and can affect their apparent color as perceived by a human observer. The aim of this study is classifying the spectral reflectance of corals base on different color. It is expected that they can be used as references in discriminating between live corals, dead coral covered with algae Spectral reflectance data was collected in three small islands, Spermonde Archipelago, Indonesia by using a hyperspectral radiometer underwater. First and second derivative analysis resolved the wavelength locations of dominant features contributing to reflectance in corals and support the distinct differences in spectra among colour existed. Spectral derivative analysis was used to determine the specific wavelength regions ideal for remote identification of substrate type. The analysis results shown that yellow, green, brown and violet live corals are spectrally separable from each other, but they are similar with dead coral covered with algae spectral.

  4. ARM Climate Research Facility Spectral Surface Albedo Value-Added Product (VAP) Report

    Energy Technology Data Exchange (ETDEWEB)

    McFarlane, S; Gaustad, K; Long, C; Mlawer, E

    2011-07-15

    This document describes the input requirements, output data products, and methodology for the Spectral Surface Albedo (SURFSPECALB) value-added product (VAP). The SURFSPECALB VAP produces a best-estimate near-continuous high spectral resolution albedo data product using measurements from multifilter radiometers (MFRs). The VAP first identifies best estimates for the MFR downwelling and upwelling shortwave irradiance values, and then calculates narrowband spectral albedo from these best-estimate irradiance values. The methodology for finding the best-estimate values is based on a simple process of screening suspect data and backfilling screened and missing data with estimated values when possible. The resulting best-estimate MFR narrowband spectral albedos are used to determine a daily surface type (snow, 100% vegetation, partial vegetation, or 0% vegetation). For non-snow surfaces, a piecewise continuous function is used to estimate a high spectral resolution albedo at 1 min temporal and 10 cm-1 spectral resolution.

  5. Spectral Decomposition Algorithm (SDA)

    Data.gov (United States)

    National Aeronautics and Space Administration — Spectral Decomposition Algorithm (SDA) is an unsupervised feature extraction technique similar to PCA that was developed to better distinguish spectral features in...

  6. Accurate frequency measurements on gyrotrons using a ''gyro-radiometer''

    International Nuclear Information System (INIS)

    Rebuffi, L.

    1986-08-01

    Using an heterodyne system, called ''Gyro-radiometer'', accurated frequency measurements have been carried out on VARIAN 60 GHz gyrotrons. Changing the principal tuning parameters of a gyrotron, we have detected frequency variations up to 100 MHz, ∼ 40 MHz frequency jumps and smaller jumps (∼ 10 MHz) when mismatches in the transmission line were present. FWHM bandwidth of 300 KHz, parasitic frequencies and frequency drift during 100 msec pulses have also been observed. An efficient method to find a stable-, high power-, long pulse-working point of a gyrotron loaded by a transmission line, has been derived. In general, for any power value it is possible to find stable working conditions tuning the principal parameters of the tube in correspondance of a maximum of the emitted frequency

  7. Total ozone retrieval from satellite multichannel filter radiometer measurements

    International Nuclear Information System (INIS)

    Lovill, J.E.; Sullivan, T.J.; Weichel, R.L.; Ellis, J.S.; Huebel, J.G.; Korver, J.; Weidhaas, P.P.; Phelps, F.A.

    1978-01-01

    A total ozone retrieval model has been developed to process radiance data gathered by a satellite-mounted multichannel filter radiometer (MFR). Extensive effort went into theoretical radiative transfer modeling, a retrieval scheme was developed, and the technique was applied to the MFR radiance measurements. The high quality of the total ozone retrieval results was determined through comparisons with Dobson measurements. Included in the report are global total ozone maps for 20 days between May 12 and July 5, 1977. A comparison of MFR results for 13 days in June 1977 with Dobson spectrophotometer measurements of ozone for the same period showed good agreement: there was a root-mean-square difference of 6.2% (equivalent to 20.2 m.atm.cm). The estimated global total ozone value for June 1977 (296 m.atm.cm) was in good agreement with satellite backscatter ultraviolet data for June 1970 (304 m.atm.cm) and June 1971

  8. Design principles and field performance of a solar spectral irradiance meter

    Energy Technology Data Exchange (ETDEWEB)

    Tatsiankou, V.; Hinzer, K.; Haysom, J.; Schriemer, H.; Emery, K.; Beal, R.

    2016-08-01

    A solar spectral irradiance meter (SSIM), designed for measuring the direct normal irradiance (DNI) in six wavelength bands, has been combined with models to determine key atmospheric transmittances and the resulting spectral irradiance distribution of DNI under all sky conditions. The design principles of the SSIM, implementation of a parameterized transmittance model, and field performance comparisons of modeled solar spectra with reference radiometer measurements are presented. Two SSIMs were tested and calibrated at the National Renewable Energy Laboratory (NREL) against four spectroradiometers and an absolute cavity radiometer. The SSIMs' DNI was on average within 1% of the DNI values reported by one of NREL's primary absolute cavity radiometers. An additional SSIM was installed at the SUNLAB Outdoor Test Facility in September 2014, with ongoing collection of environmental and spectral data. The SSIM's performance in Ottawa was compared against a commercial pyrheliometer and a spectroradiometer over an eight month study. The difference in integrated daily spectral irradiance between the SSIM and the ASD spectroradiometer was found to be less than 1%. The cumulative energy density collected by the SSIM over this duration agreed with that measured by an Eppley model NIP pyrheliometer to within 0.5%. No degradation was observed.

  9. Data Retrieval Algorithm and Uncertainty Analysis for a Miniaturized, Laser Heterodyne Radiometer

    Science.gov (United States)

    Miller, J. H.; Melroy, H.; Wilson, E. L.; Clarke, G. B.

    2013-12-01

    In a collaboration between NASA Goddard Space Flight Center and George Washington University, a low-cost, surface instrument is being developed that can continuously monitor key carbon cycle gases in the atmospheric column: carbon dioxide (CO2) and methane (CH4). The instrument is based on a miniaturized, laser heterodyne radiometer (LHR) using near infrared (NIR) telecom lasers. Despite relatively weak absorption line strengths in this spectral region, spectrally-resolved atmospheric column absorptions for these two molecules fall in the range of 60-80% and thus sensitive and precise measurements of column concentrations are possible. Further, because the LHR technique has the potential for sub-Doppler spectral resolution, the possibility exists for interrogating line shapes to extract altitude profiles of the greenhouse gases. From late 2012 through 2013 the instrument was deployed for a variety of field measurements including at Park Falls, Wisconsin; Castle Airport near Atwater, California; and at the NOAA Mauna Loa Observatory in Hawaii. For each subsequent campaign, improvement in the figures of merit for the instrument (notably spectral sweep time and absorbance noise) has been observed. For the latter, the absorbance noise is approaching 0.002 optical density (OD) noise on a 1.8 OD signal. This presentation presents an overview of the measurement campaigns in the context of the data retrieval algorithm under development at GW for the calculation of column concentrations from them. For light transmission through the atmosphere, it is necessary to account for variation of pressure, temperature, composition, and refractive index through the atmosphere that are all functions of latitude, longitude, time of day, altitude, etc. In our initial work we began with coding developed under the LOWTRAN and MODTRAN programs by the AFOSR (and others). We also assumed temperature and pressure profiles from the 1976 US Standard Atmosphere and used the US Naval Observatory

  10. The Impact of Indoor and Outdoor Radiometer Calibration on Solar Measurements: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Habte, Aron; Sengupta, Manajit; Andreas, Afshin; Reda, Ibrahim; Robinson, Justin

    2016-07-01

    Accurate solar radiation data sets are critical to reducing the expenses associated with mitigating performance risk for solar energy conversion systems, and they help utility planners and grid system operators understand the impacts of solar resource variability. The accuracy of solar radiation measured by radiometers depends on the instrument performance specification, installation method, calibration procedure, measurement conditions, maintenance practices, location, and environmental conditions. This study addresses the effect of calibration methodologies and the resulting calibration responsivities provided by radiometric calibration service providers such as the National Renewable Energy Laboratory (NREL) and manufacturers of radiometers. Some of these radiometers are calibrated indoors, and some are calibrated outdoors. To establish or understand the differences in calibration methodology, we processed and analyzed field-measured data from these radiometers. This study investigates calibration responsivities provided by NREL's broadband outdoor radiometer calibration (BORCAL) and a few prominent manufacturers. The reference radiometer calibrations are traceable to the World Radiometric Reference. These different methods of calibration demonstrated 1% to 2% differences in solar irradiance measurement. Analyzing these values will ultimately assist in determining the uncertainties of the radiometer data and will assist in developing consensus on a standard for calibration.

  11. Evaluation of Radiometers Deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Habte, Aron; Wilcox, Stephen; Stoffel, Thomas

    2015-12-23

    This study analyzes the performance of various commercially available radiometers used for measuring global horizontal irradiances and direct normal irradiances. These include pyranometers, pyrheliometers, rotating shadowband radiometers, and a pyranometer with fixed internal shading and are all deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory. Data from 32 global horizontal irradiance and 19 direct normal irradiance radiometers are presented. The radiometers in this study were deployed for one year (from April 1, 2011, through March 31, 2012) and compared to measurements from radiometers with the lowest values of estimated measurement uncertainties for producing reference global horizontal irradiances and direct normal irradiances.

  12. Application of RUB-01P beta radiometer to control contamination of milk and dairy produce

    International Nuclear Information System (INIS)

    Bachurin, A.V.; Donskaya, G.A.; Koroleva, M.S.; Titov, S.K.

    1990-01-01

    RUB-01P beta-radiometer to control radioactive contamination of milk and dairy produce characterized by a number of advantages as compared to RKB-4-1eM manufactured earlier is described. Device is designed using a new element base, simgle-action, characterized by increased reliability, can operate on-line with ELEKTRONIKA MK-64 programmed microcalculater. Radiometer output is printed out to a void operator errors and to record measurement results. Radiometer main error is maximum 50 %. Data on device sensitivity at measurements using BDZhB-05P, BDZhB-06P1, BDZhB-06P detection units are given

  13. Processor breadboard for on-board RFI detection and mitigation in MetOp-SG radiometers

    DEFF Research Database (Denmark)

    Skou, Niels; Kristensen, Steen S.; Kovanen, Arhippa

    2015-01-01

    Radio Frequency Interference (RFI) is an increasing threat to proper operation of space-borne Earth viewing microwave radiometer systems. There is a steady growth in active services, and tougher requirements to sensitivity and fidelity of future radiometer systems. Thus it has been decided...... that the next generation MetOp satellites must include some kind of RFI detection and mitigation system at Ku band. This paper describes a breadboard processor that detects and mitigates RFI on-board the satellite. Thus cleaned data can be generated in real time, and following suitable integration, downloaded...... to ground at the modest data rate usually associated with radiometer systems....

  14. An optical scanning subsystem for a UAS-enabled hyperspectral radiometer

    Data.gov (United States)

    National Aeronautics and Space Administration — Hyperspectral radiometers will be integrated with an optical scanning subsystem to measure remote sensing reflectance spectra over the ocean.  The entire scanning...

  15. GPM GROUND VALIDATION ADVANCED MICROWAVE RADIOMETER RAIN IDENTIFICATION (ADMIRARI) GCPEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Advanced Microwave Radiometer Rain Identification (ADMIRARI) GCPEx dataset measures brightness temperature at three frequencies (10.7, 21.0...

  16. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Snow Cover Environmental Data Record (EDR) from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of snow cover from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument...

  17. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Smoothed Normalized Difference Vegetation Index (NDVI) from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Visible Infrared Imaging Radiometer Suite (VIIRS) Smoothed Normalized Difference Vegetation Index (NDVI) from NDE is a weekly product derived from the VIIRS...

  18. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Aerosol Detection Environmental Data Record (EDR) from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of suspended matter from the Visible Infrared Imaging Radiometer Suite (VIIRS)...

  19. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Sensor Data Record (SDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Sensor Data Records (SDRs), or Level 1b data, from the Visible Infrared Imaging Radiometer Suite (VIIRS) are the calibrated and geolocated radiance and reflectance...

  20. Low level beta-activity radiometer with compensation of the background

    Energy Technology Data Exchange (ETDEWEB)

    Vankov, I [and others

    1996-12-31

    New type of the low level beta-activity scintillation detector system is developed. The procedure of finding the beta activity and the operation of the recording unit of the radiometer are considered. 3 refs.; 5 figs.

  1. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Cloud Mask Environmental Data Record (EDR) from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains a high quality Environmental Data Record (EDR) of cloud masks from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument onboard...

  2. Effect of vegetation on soil moisture sensing observed from orbiting microwave radiometers

    International Nuclear Information System (INIS)

    Wang, J.R.

    1985-01-01

    The microwave radiometric measurements made by the Skylab 1.4 GHz radiometer and by the 6.6 GHz and 10.7 GHz channels of the Nimbus-7 Scanning Multichannel Microwave Radiometer were analyzed to study the large-area soil moisture variations of land surfaces. Two regions in Texas, one with sparse and the other with dense vegetation covers, were selected for the study. The results gave a confirmation of the vegetation effect observed by ground-level microwave radiometers. Based on the statistics of the satellite data, it was possible to estimate surface soil moisture in about five different levels from dry to wet conditions with a 1.4 GHz radiometer, provided that the biomass of the vegetation cover could be independently measured. At frequencies greater than about 6.6 GHz, the radiometric measurements showed little sensitivity to moisture variation for vegetation-covered soils. The effects of polarization in microwave emission were studied also. (author)

  3. Nimbus-2 Level 2 Medium Resolution Infrared Radiometer (MRIR) V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The Nimbus II Medium Resolution Infrared Radiometer (MRIR) was designed to measure electromagnetic radiation emitted and reflected from the earth and its atmosphere...

  4. Scanning Multichannel Microwave Radiometer (SMMR) Monthly Mean Atmospheric Liquid Water (ALW) By Prabhakara

    Data.gov (United States)

    National Aeronautics and Space Administration — SMMR_ALW_PRABHAKARA data are Special Multichannel Microwave Radiometer (SMMR) Monthly Mean Atmospheric Liquid Water (ALW) data by Prabhakara.The Prabhakara Scanning...

  5. The Aquarius Ocean Salinity Mission High Stability L-band Radiometer

    Science.gov (United States)

    Pellerano, Fernando A.; Piepmeier, Jeffrey; Triesky, Michael; Horgan, Kevin; Forgione, Joshua; Caldwell, James; Wilson, William J.; Yueh, Simon; Spencer, Michael; McWatters, Dalia; hide

    2006-01-01

    The NASA Earth Science System Pathfinder (ESSP) mission Aquarius, will measure global ocean surface salinity with approx.120 km spatial resolution every 7-days with an average monthly salinity accuracy of 0.2 psu (parts per thousand). This requires an L-band low-noise radiometer with the long-term calibration stability of less than or equal to 0.15 K over 7 days. The instrument utilizes a push-broom configuration which makes it impractical to use a traditional warm load and cold plate in front of the feedhorns. Therefore, to achieve the necessary performance Aquarius utilizes a Dicke radiometer with noise injection to perform a warm - hot calibration. The radiometer sequence between antenna, Dicke load, and noise diode has been optimized to maximize antenna observations and therefore minimize NEDT. This is possible due the ability to thermally control the radiometer electronics and front-end components to 0.1 Crms over 7 days.

  6. Evaluating Solar Resource Data Obtained from Multiple Radiometers Deployed at the National Renewable Energy Laboratory: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Habte, A.; Sengupta, M.; Andreas, A.; Wilcox, S.; Stoffel, T.

    2014-09-01

    Solar radiation resource measurements from radiometers are used to predict and evaluate the performance of photovoltaic and concentrating solar power systems, validate satellite-based models for estimating solar resources, and advance research in solar forecasting and climate change. This study analyzes the performance of various commercially available radiometers used for measuring global horizontal irradiances (GHI) and direct normal irradiances (DNI). These include pyranometers, pyrheliometers, rotating shadowband irradiometers, and a pyranometer with a shading ring deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory (SRRL). The radiometers in this study were deployed for one year (from April 1, 2011, through March 31, 2012) and compared to measurements from radiometers with the lowest values of estimated measurement uncertainties for producing reference GHI and DNI.

  7. Next-Generation Thermal Infrared Multi-Body Radiometer Experiment (TIMBRE)

    Science.gov (United States)

    Kenyon, M.; Mariani, G.; Johnson, B.; Brageot, E.; Hayne, P.

    2016-10-01

    We have developed an instrument concept called TIMBRE which belongs to the important class of instruments called thermal imaging radiometers (TIRs). TIMBRE is the next-generation TIR with unparalleled performance compared to the state-of-the-art.

  8. The Planck-LFI Radiometer Electronics Box Assembly

    International Nuclear Information System (INIS)

    Herreros, J M; Gomez, M F; Rebolo, R; Chulani, H; Rubino-Martin, J A; Hildebrandt, S R; Bersanelli, M; Franceschet, C; Butler, R C; Miccolis, M; Pena, A; Pereira, M; Torrero, F; Lopez, M; Alcala, C

    2009-01-01

    The Radiometer Electronics Box Assembly (REBA) is the control and data processing on board computer of the Low Frequency Instrument (LFI) of the Planck mission (ESA). The REBA was designed and built incorporating state of the art processors, communication interfaces and real time operating system software in order to meet the scientific performance of the LFI. We present a technical summary of the REBA, including a physical, functional, electrical, mechanical and thermal description. Aspects of the design and development, the assembly, the integration and the verification of the equipment are provided. A brief description of the LFI on board software is given including the Low-Level Software and the main functionalities and architecture of the Application Software. The compressor module, which has been developed as an independent product, later integrated in the application, is also described in this paper. Two identical engineering models EM and AVM, the engineering qualification model EQM, the flight model FM and flight spare have been manufactured and tested. Low-level and Application software have been developed. Verification activities demonstrated that the REBA hardware and software fulfil all the specifications and perform as required for flight operation.

  9. The Planck-LFI Radiometer Electronics Box Assembly

    Science.gov (United States)

    Herreros, J. M.; Gómez, M. F.; Rebolo, R.; Chulani, H.; Rubiño-Martin, J. A.; Hildebrandt, S. R.; Bersanelli, M.; Butler, R. C.; Miccolis, M.; Peña, A.; Pereira, M.; Torrero, F.; Franceschet, C.; López, M.; Alcalá, C.

    2009-12-01

    The Radiometer Electronics Box Assembly (REBA) is the control and data processing on board computer of the Low Frequency Instrument (LFI) of the Planck mission (ESA). The REBA was designed and built incorporating state of the art processors, communication interfaces and real time operating system software in order to meet the scientific performance of the LFI. We present a technical summary of the REBA, including a physical, functional, electrical, mechanical and thermal description. Aspects of the design and development, the assembly, the integration and the verification of the equipment are provided. A brief description of the LFI on board software is given including the Low-Level Software and the main functionalities and architecture of the Application Software. The compressor module, which has been developed as an independent product, later integrated in the application, is also described in this paper. Two identical engineering models EM and AVM, the engineering qualification model EQM, the flight model FM and flight spare have been manufactured and tested. Low-level and Application software have been developed. Verification activities demonstrated that the REBA hardware and software fulfil all the specifications and perform as required for flight operation.

  10. CIRiS: Compact Infrared Radiometer in Space

    Science.gov (United States)

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

    2016-09-01

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

  11. The Planck-LFI Radiometer Electronics Box Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Herreros, J M; Gomez, M F; Rebolo, R; Chulani, H; Rubino-Martin, J A; Hildebrandt, S R [Instituto de Astrofisica de Canarias (IAC), 38200 La Laguna, Tenerife (Spain); Bersanelli, M; Franceschet, C [Universita di Milano, Dipartamento di Fisica, Via G. Celoria 16, 20133 Milano (Italy); Butler, R C [INAF-IASF Bologna, Via P. Gobetti 101, 40129 Bologna (Italy); Miccolis, M [Thales Alenia Space Italia S.p.A., IUEL - Scientific Instruments, S.S. Padana Superiore 290, 20090 Vimodrone (Italy); Pena, A; Pereira, M; Torrero, F; Lopez, M; Alcala, C, E-mail: rrl@iac.e [EADS Astrium CRISA, C/Torres Quevedo, 9, 28760 Tres Cantos (Spain)

    2009-12-15

    The Radiometer Electronics Box Assembly (REBA) is the control and data processing on board computer of the Low Frequency Instrument (LFI) of the Planck mission (ESA). The REBA was designed and built incorporating state of the art processors, communication interfaces and real time operating system software in order to meet the scientific performance of the LFI. We present a technical summary of the REBA, including a physical, functional, electrical, mechanical and thermal description. Aspects of the design and development, the assembly, the integration and the verification of the equipment are provided. A brief description of the LFI on board software is given including the Low-Level Software and the main functionalities and architecture of the Application Software. The compressor module, which has been developed as an independent product, later integrated in the application, is also described in this paper. Two identical engineering models EM and AVM, the engineering qualification model EQM, the flight model FM and flight spare have been manufactured and tested. Low-level and Application software have been developed. Verification activities demonstrated that the REBA hardware and software fulfil all the specifications and perform as required for flight operation.

  12. Regolith Formation Rates and Evolution from the Diviner Lunar Radiometer

    Science.gov (United States)

    Hayne, P. O.; Ghent, R. R.; Bandfield, J. L.; Vasavada, A. R.; Williams, J. P.; Siegler, M. A.; Lucey, P. G.; Greenhagen, B. T.; Elder, C. M.; Paige, D. A.

    2015-12-01

    Fragmentation and overturn of lunar surface materials produces a layer of regolith, which increases in thickness through time. Experiments on the lunar surface during the Apollo era, combined with remote sensing, found that the upper 10's of cm of regolith exhibit a rapid increase in density and thermal conductivity with depth. This is interpreted to be the signature of impact gardening, which operates most rapidly in the uppermost layers. Gravity data from the GRAIL mission showed that impacts have also extensively fractured the deeper crust. The breakdown and mixing of crustal materials is therefore a central process to lunar evolution and must be understood in order to interpret compositional information from remote sensing and sample analysis. Recently, thermal infrared data from the Lunar Reconnaissance Orbiter (LRO) Diviner radiometer were used to provide the first remote observational constraints on the rate of ejecta breakdown around craters L., Campbell, B. A., Allen, C. C., Carter, L. M., & Paige, D. A. (2014). Constraints on the recent rate of lunar ejecta breakdown and implications for crater ages. Geology, 42(12), 1059-1062.

  13. Daily quality assurance software for a satellite radiometer system

    Science.gov (United States)

    Keegstra, P. B.; Smoot, G. F.; Bennett, C. L.; Aymon, J.; Backus, C.; Deamici, G.; Hinshaw, G.; Jackson, P. D.; Kogut, A.; Lineweaver, C.

    1992-01-01

    Six Differential Microwave Radiometers (DMR) on COBE (Cosmic Background Explorer) measure the large-angular-scale isotropy of the cosmic microwave background (CMB) at 31.5, 53, and 90 GHz. Quality assurance software analyzes the daily telemetry from the spacecraft to ensure that the instrument is operating correctly and that the data are not corrupted. Quality assurance for DMR poses challenging requirements. The data are differential, so a single bad point can affect a large region of the sky, yet the CMB isotropy requires lengthy integration times (greater than 1 year) to limit potential CMB anisotropies. Celestial sources (with the exception of the moon) are not, in general, visible in the raw differential data. A 'quicklook' software system was developed that, in addition to basic plotting and limit-checking, implements a collection of data tests as well as long-term trending. Some of the key capabilities include the following: (1) stability analysis showing how well the data RMS averages down with increased data; (2) a Fourier analysis and autocorrelation routine to plot the power spectrum and confirm the presence of the 3 mK 'cosmic' dipole signal; (3) binning of the data against basic spacecraft quantities such as orbit angle; (4) long-term trending; and (5) dipole fits to confirm the spacecraft attitude azimuth angle.

  14. Determination of total ozone from DMSP multichannel filter radiometer measurements

    International Nuclear Information System (INIS)

    Luther, F.M.; Weichel, R.L.

    1992-01-01

    The multichannel filter radiometer (MFR) infrared sensor was first flown in 1977 on a Defense Meteorological Satellite Program (DMSP) Block 5D series satellite operated by the US Air Force. The first four satellites in this series carried MFR sensors from which total atmospheric column ozone amounts may be derived. The MFR sensor was the first cross-track scanning sensor capable of measuring ozone. MFR sensor infrared measurements are taken day and night. The satellites are in polar sun-synchronous orbits providing daily global coverage. The series of four sensors spans a data period of nearly three years. The MFR sensor measures infrared radiances for 16 channels. Total ozone amounts are determined from sets of radiance measurements using an empirical relationship that is developed using linear regression analysis. Total ozone is modeled as a linear combination of terms involving functions of the MFR radiances for four channels (1, 3, 7 and 16) and the secant of the zenith angle. The MFR scans side to side in discrete steps of 40. The MFR sensor takes infrared radiance measurements at 25 cross-track scanning locations every 32 seconds. The instrument could take a theoretical maximum of 67,500 measurements per day, although typically 35,000 - 45,000 measurements are taken per day

  15. PERBANDINGAN PENGUKURAN RADIOMETER DAN RADIOSONDE PADA MUSIM HUJAN DI DRAMAGA BOGOR

    OpenAIRE

    Athoillah, Ibnu; Dewi, Saraswati; Renggono, Findy

    2016-01-01

    IntisariBalai Besar Teknologi Modifikasi Cuaca (BB-TMC) BPPT bekerjasama dengan Badan Meteorologi Klimatologi dan Geofisika (BMKG) melakukan kegiatan Intensive Observation Period (IOP) selama puncak musim hujan pada tanggal 18 Januari - 16 Februari 2016 di wilayah Jabodetabek. Salah satu peralatan yang digunakan untuk observasi adalah Radiometer dan Radiosonde. Pada penelitian ini akan difokuskan bagaimana perbandingan hasil dari pengukuran Radiometer dan Radiosonde selama kegiatan IOP teruta...

  16. CAROLS: A New Airborne L-Band Radiometer for Ocean Surface and Land Observations

    Directory of Open Access Journals (Sweden)

    Ernesto Lopez-Baeza

    2011-01-01

    Full Text Available The “Cooperative Airborne Radiometer for Ocean and Land Studies” (CAROLS L-Band radiometer was designed and built as a copy of the EMIRAD II radiometer constructed by the Technical University of Denmark team. It is a fully polarimetric and direct sampling correlation radiometer. It is installed on board a dedicated French ATR42 research aircraft, in conjunction with other airborne instruments (C-Band scatterometer—STORM, the GOLD-RTR GPS system, the infrared CIMEL radiometer and a visible wavelength camera. Following initial laboratory qualifications, three airborne campaigns involving 21 flights were carried out over South West France, the Valencia site and the Bay of Biscay (Atlantic Ocean in 2007, 2008 and 2009, in coordination with in situ field campaigns. In order to validate the CAROLS data, various aircraft flight patterns and maneuvers were implemented, including straight horizontal flights, circular flights, wing and nose wags over the ocean. Analysis of the first two campaigns in 2007 and 2008 leads us to improve the CAROLS radiometer regarding isolation between channels and filter bandwidth. After implementation of these improvements, results show that the instrument is conforming to specification and is a useful tool for Soil Moisture and Ocean Salinity (SMOS satellite validation as well as for specific studies on surface soil moisture or ocean salinity.

  17. Spectral gamuts and spectral gamut mapping

    Science.gov (United States)

    Rosen, Mitchell R.; Derhak, Maxim W.

    2006-01-01

    All imaging devices have two gamuts: the stimulus gamut and the response gamut. The response gamut of a print engine is typically described in CIE colorimetry units, a system derived to quantify human color response. More fundamental than colorimetric gamuts are spectral gamuts, based on radiance, reflectance or transmittance units. Spectral gamuts depend on the physics of light or on how materials interact with light and do not involve the human's photoreceptor integration or brain processing. Methods for visualizing a spectral gamut raise challenges as do considerations of how to utilize such a data-set for producing superior color reproductions. Recent work has described a transformation of spectra reduced to 6-dimensions called LabPQR. LabPQR was designed as a hybrid space with three explicit colorimetric axes and three additional spectral reconstruction axes. In this paper spectral gamuts are discussed making use of LabPQR. Also, spectral gamut mapping is considered in light of the colorimetric-spectral duality of the LabPQR space.

  18. Greenhouse Gas Concentration Data Recovery Algorithm for a Low Cost, Laser Heterodyne Radiometer

    Science.gov (United States)

    Miller, J. Houston; Melroy, Hilary R.; Ott, Lesley E.; Mclinden, Matthew L.; Holben, Brent; Wilson, Emily L.

    2012-01-01

    The goal of a coordinated effort between groups at GWU and NASA GSFC is the development of a low-cost, global, surface instrument network that continuously monitors three key carbon cycle gases in the atmospheric column: carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), as well as oxygen (O2) for atmospheric pressure profiles. The network will implement a low-cost, miniaturized, laser heterodyne radiometer (mini-LHR) that has recently been developed at NASA Goddard Space Flight Center. This mini-LHR is designed to operate in tandem with the passive aerosol sensor currently used in AERONET (a well established network of more than 450 ground aerosol monitoring instruments worldwide), and could be rapidly deployed into this established global network. Laser heterodyne radiometry is a well-established technique for detecting weak signals that was adapted from radio receiver technology. Here, a weak light signal, that has undergone absorption by atmospheric components, is mixed with light from a distributed feedback (DFB) telecommunications laser on a single-mode optical fiber. The RF component of the signal is detected on a fast photoreceiver. Scanning the laser through an absorption feature in the infrared, results in a scanned heterodyne signal io the RF. Deconvolution of this signal through the retrieval algorithm allows for the extraction of altitude contributions to the column signal. The retrieval algorithm is based on a spectral simulation program, SpecSyn, developed at GWU for high-resolution infrared spectroscopies. Variations io pressure, temperature, composition, and refractive index through the atmosphere; that are all functions of latitude, longitude, time of day, altitude, etc.; are modeled using algorithms developed in the MODTRAN program developed in part by the US Air Force Research Laboratory. In these calculations the atmosphere is modeled as a series of spherically symmetric shells with boundaries specified at defined altitudes. Temperature

  19. Greenhouse Gas Concentration Data Recovery Algorithm for a Low Cost, Laser Heterodyne Radiometer

    Science.gov (United States)

    Miller, J. H.; Melroy, H.; Ott, L.; McLinden, M. L.; Holben, B. N.; Wilson, E. L.

    2012-12-01

    The goal of a coordinated effort between groups at GWU and NASA GSFC is the development of a low-cost, global, surface instrument network that continuously monitors three key carbon cycle gases in the atmospheric column: carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), as well as oxygen (O2) for atmospheric pressure profiles. The network will implement a low-cost, miniaturized, laser heterodyne radiometer (mini-LHR) that has recently been developed at NASA Goddard Space Flight Center. This mini-LHR is designed to operate in tandem with the passive aerosol sensor currently used in AERONET (a well established network of more than 450 ground aerosol monitoring instruments worldwide), and could be rapidly deployed into this established global network. Laser heterodyne radiometry is a well-established technique for detecting weak signals that was adapted from radio receiver technology. Here, a weak light signal, that has undergone absorption by atmospheric components, is mixed with light from a distributed feedback (DFB) telecommunications laser on a single-mode optical fiber. The RF component of the signal is detected on a fast photoreceiver. Scanning the laser through an absorption feature in the infrared, results in a scanned heterodyne signal in the RF. Deconvolution of this signal through the retrieval algorithm allows for the extraction of altitude contributions to the column signal. The retrieval algorithm is based on a spectral simulation program, SpecSyn, developed at GWU for high-resolution infrared spectroscopies. Variations in pressure, temperature, composition, and refractive index through the atmosphere; that are all functions of latitude, longitude, time of day, altitude, etc.; are modeled using algorithms developed in the MODTRAN program developed in part by the US Air Force Research Laboratory. In these calculations the atmosphere is modeled as a series of spherically symmetric shells with boundaries specified at defined altitudes. Temperature

  20. Ground-Based Correction of Remote-Sensing Spectral Imagery

    Science.gov (United States)

    Alder-Golden, Steven M.; Rochford, Peter; Matthew, Michael; Berk, Alexander

    2007-01-01

    Software has been developed for an improved method of correcting for the atmospheric optical effects (primarily, effects of aerosols and water vapor) in spectral images of the surface of the Earth acquired by airborne and spaceborne remote-sensing instruments. In this method, the variables needed for the corrections are extracted from the readings of a radiometer located on the ground in the vicinity of the scene of interest. The software includes algorithms that analyze measurement data acquired from a shadow-band radiometer. These algorithms are based on a prior radiation transport software model, called MODTRAN, that has been developed through several versions up to what are now known as MODTRAN4 and MODTRAN5 . These components have been integrated with a user-friendly Interactive Data Language (IDL) front end and an advanced version of MODTRAN4. Software tools for handling general data formats, performing a Langley-type calibration, and generating an output file of retrieved atmospheric parameters for use in another atmospheric-correction computer program known as FLAASH have also been incorporated into the present soft-ware. Concomitantly with the soft-ware described thus far, there has been developed a version of FLAASH that utilizes the retrieved atmospheric parameters to process spectral image data.

  1. Interpretation of UV radiometric measurements of spectrally non-uniform sources

    International Nuclear Information System (INIS)

    Murphy, P.J.; Gardner, D.G.

    1988-01-01

    Narrow bandpass UV radiometers are used in a variety of high-temperature measurement applications. Significant systematic errors, in the form of an apparent wavelength shift in the system response curve, may be introduced when interpreting data obtained from spectrally nonuniform sources. Theoretical calculations, using transmission curves from commercially available narrow bandpass filters, show that the apparent shift in the system spectral response is a function of temperature for a blackbody source. A brief comparison between the theoretical analysis and experimentaal data is presented

  2. Spectral composition of shortwave radiation reflected and deep penetrating into snow near the Barentsburg settlement (Svalbard

    Directory of Open Access Journals (Sweden)

    P. N. Svyashchennikov

    2015-01-01

    Full Text Available Data on spectral composition of shortwave radiation that is reflected from snow and penetrates deep into the snow cover obtained near the Barentsburg settlement (Svalbard are discussed in the paper. Measurements were made by the use of the spectral radiometer TriOS Ramses within the wavelength range of 280–950 nm. The results will allow more proper taking account of the anthropogenic pollution effects on the radiative properties of snow cover under conditions of industrial activity related to the coal extraction and burning in Barentsburg.

  3. Analysis of dust and marine aerosol optical depth spectral-curvature information in the UV to SWIR (Short Wave Infrared) wavelength regions.

    Science.gov (United States)

    O'Neill, N. T.; Smirnov, A.; Eck, T. F.; Sakerin, S.; Kabanov, D.

    2005-12-01

    Traditional sunphotometry in the UV, visible and very NIR (Near Infrared) spectral regions is weighted, in terms of spectral information content, towards sub-micron (fine mode) particles. Sunphotometry in the NIR and SWIR increases the diversity and information content of spectral aerosol optical depth (AOD) measurements for supermicron (coarse mode) particles. Two data sets representing dust aerosols from the UAE (United Arab Emirates) region and marine aerosols from the northern, tropical and southern Atlantic Ocean were analyzed in terms of their spectral curvature diversity and information content. The former data set was acquired using NIR-enhanced CIMEL sunphotometers (340, 340, 380, 440, 500, 670, 870, 1020, 1640 nm) as part of the August to October, 2004 UAE2 field campaign while the latter data set was acquired using an automated Russian UV to SWIR SP-5 sunphotometer (339, 423, 438, 484, 552, 633, 677, 777, 869, 1241, 1560, 2148, 4000 nm) as part of a October/December 2004 cruise campaign in the northern, tropical and south Atlantic Ocean. A Microtops hand-held sunphotometer was also employed to acquire VIS to NIR AOD spectra during the latter field campaign. Results will be presented in terms of robust micro-physical and spectral curvature parameters which characterize super-micron aerosols and, in a more general sense, in terms of what universal/fundamental optical inferences can be drawn from the two disperse data sets.

  4. Calibration OGSEs for multichannel radiometers for Mars atmosphere studies

    Science.gov (United States)

    Jiménez, J. J.; J Álvarez, F.; Gonzalez-Guerrero, M.; Apéstigue, V.; Martín, I.; Fernández, J. M.; Fernán, A. A.; Arruego, I.

    2018-06-01

    This work describes several Optical Ground Support Equipment (OGSEs) developed by INTA (Spanish Institute of Aerospace Technology—Instituto Nacional de Técnica Aeroespacial) for the calibration and characterization of their self-manufactured multichannel radiometers (solar irradiance sensors—SIS) developed for working on the surface of Mars and studying the atmosphere of that planet. Nowadays, INTA is developing two SIS for the ESA ExoMars 2020 and for the JPL/NASA Mars 2020 missions. These calibration OGSEs have been improved since the first model in 2011 developed for Mars MetNet Precursor mission. This work describes the currently used OGSE. Calibration tests provide an objective evidence of the SIS performance, allowing the conversion of the electrical sensor output into accurate physical measurements (irradiance) with uncertainty bounds. Calibration results of the SIS on board of the Dust characterisation, Risk assessment, and Environment Analyzer on the Martian Surface (DREAMS) on board the ExoMars 2016 Schiaparelli module (EDM—entry and descent module) are also presented, as well as their error propagation. Theoretical precision and accuracy of the instrument are determined by these results. Two types of OGSE are used as a function of the pursued aim: calibration OGSEs and Optical Fast Verification (OFV) GSE. Calibration OGSEs consist of three setups which characterize with the highest possible accuracy, the responsivity, the angular response and the thermal behavior; OFV OGSE verify that the performance of the sensor is close to nominal after every environmental and qualification test. Results show that the accuracy of the calibrated sensors is a function of the accuracy of the optical detectors and of the light conditions. For normal direct incidence and diffuse light, the accuracy is in the same order of uncertainty as that of the reference cell used for fixing the irradiance, which is about 1%.

  5. Calibration OGSEs for multichannel radiometers for Mars atmosphere studies

    Science.gov (United States)

    Jiménez, J. J.; J Álvarez, F.; Gonzalez-Guerrero, M.; Apéstigue, V.; Martín, I.; Fernández, J. M.; Fernán, A. A.; Arruego, I.

    2018-02-01

    This work describes several Optical Ground Support Equipment (OGSEs) developed by INTA (Spanish Institute of Aerospace Technology—Instituto Nacional de Técnica Aeroespacial) for the calibration and characterization of their self-manufactured multichannel radiometers (solar irradiance sensors—SIS) developed for working on the surface of Mars and studying the atmosphere of that planet. Nowadays, INTA is developing two SIS for the ESA ExoMars 2020 and for the JPL/NASA Mars 2020 missions. These calibration OGSEs have been improved since the first model in 2011 developed for Mars MetNet Precursor mission. This work describes the currently used OGSE. Calibration tests provide an objective evidence of the SIS performance, allowing the conversion of the electrical sensor output into accurate physical measurements (irradiance) with uncertainty bounds. Calibration results of the SIS on board of the Dust characterisation, Risk assessment, and Environment Analyzer on the Martian Surface (DREAMS) on board the ExoMars 2016 Schiaparelli module (EDM—entry and descent module) are also presented, as well as their error propagation. Theoretical precision and accuracy of the instrument are determined by these results. Two types of OGSE are used as a function of the pursued aim: calibration OGSEs and Optical Fast Verification (OFV) GSE. Calibration OGSEs consist of three setups which characterize with the highest possible accuracy, the responsivity, the angular response and the thermal behavior; OFV OGSE verify that the performance of the sensor is close to nominal after every environmental and qualification test. Results show that the accuracy of the calibrated sensors is a function of the accuracy of the optical detectors and of the light conditions. For normal direct incidence and diffuse light, the accuracy is in the same order of uncertainty as that of the reference cell used for fixing the irradiance, which is about 1%.

  6. Sensitivity of spectral indices to CO2 fluxes for several plant communities in a Sphagnum-dominated peatland

    International Nuclear Information System (INIS)

    Letendre, J.; Poulin, M.; Rochefort, L.

    2008-01-01

    A study was conducted in which the relationship between spectral indices and carbon dioxide (CO 2 ) fluxes was tested for different communities in a Sphagnum-dominated peatland. This paper focused on the remote sensing approach that was used to directly link spectral indices to CO 2 fluxes to highlight the potential of remote sensing for mapping the spatial distribution of CO 2 fluxes. Carbon exchange in these ecosystems has become an environmental concern since peatlands play a key role in the global carbon cycle. A portable climate-controlled chamber was used to measure fluxes while simultaneously recording reflectance with a hand-held spectroradiometer. A laboratory experiment was also conducted to find a water-related index that most correlated with Sphagnum water content in order to regulate the normalized difference vegetation index (NDVI) values obtained in the field. The laboratory experiment showed a strong correlation between Sphagnum water content and all spectral indices, notably the water index (WI), normalized difference water index (NDWI), and relative depth index (RDI). The water index was chosen to regulate NDVI values. This paper described the indices that were tested in the field for CO 2 flux estimations. NDVI alone was found to be a poor predictor of net ecosystem exchange. The relationship between CO 2 fluxes and narrow band chlorophyll indices was reasonably well adjusted. It was concluded that the chlorophyll indices may be the most promising for mapping the spatial distribution of CO 2 fluxes in the future. 62 refs., 2 tabs., 4 figs

  7. Low Average Sidelobe Slot Array Antennas for Radiometer Applications

    Science.gov (United States)

    Rengarajan, Sembiam; Zawardzki, Mark S.; Hodges, Richard E.

    2012-01-01

    In radiometer applications, it is required to design antennas that meet low average sidelobe levels and low average return loss over a specified frequency bandwidth. It is a challenge to meet such specifications over a frequency range when one uses resonant elements such as waveguide feed slots. In addition to their inherent narrow frequency band performance, the problem is exacerbated due to modeling errors and manufacturing tolerances. There was a need to develop a design methodology to solve the problem. An iterative design procedure was developed by starting with an array architecture, lattice spacing, aperture distribution, waveguide dimensions, etc. The array was designed using Elliott s technique with appropriate values of the total slot conductance in each radiating waveguide, and the total resistance in each feed waveguide. Subsequently, the array performance was analyzed by the full wave method of moments solution to the pertinent integral equations. Monte Carlo simulations were also carried out to account for amplitude and phase errors introduced for the aperture distribution due to modeling errors as well as manufacturing tolerances. If the design margins for the average sidelobe level and the average return loss were not adequate, array architecture, lattice spacing, aperture distribution, and waveguide dimensions were varied in subsequent iterations. Once the design margins were found to be adequate, the iteration was stopped and a good design was achieved. A symmetric array architecture was found to meet the design specification with adequate margin. The specifications were near 40 dB for angular regions beyond 30 degrees from broadside. Separable Taylor distribution with nbar=4 and 35 dB sidelobe specification was chosen for each principal plane. A non-separable distribution obtained by the genetic algorithm was found to have similar characteristics. The element spacing was obtained to provide the required beamwidth and close to a null in the E

  8. Improvement of shipborne sky radiometer and its demonstration aboard the Antarctic research vessel Shirase

    Directory of Open Access Journals (Sweden)

    Noriaki Tanaka

    2014-11-01

    Full Text Available The sun-tracking performance of a shipborne sky radiometer was improved to attain accurate aerosol optical thickness (AOT from direct solar measurements on a pitching and rolling vessel. Improvements were made in the accuracy of sun-pointing measurements, field-of-view expansion, sun-tracking speed, and measurement method. Radiometric measurements of direct solar and sky brightness distribution were performed using the shipborne sky radiometer onboard the Antarctic research vessel (R/V Shirase during JARE-51 (2009-2010 and JARE-52 (2010-2011. The temporal variation of signal intensity measured by the radiometer under cloudless conditions was smooth, demonstrating that the radiometer could measure direct sunlight onboard the R/V. AOT at 500 nm ranged from 0.01 to 0.34, and values over Southeast Asia and over the western Pacific Ocean in spring were higher than those over other regions. The Angstrom exponent ranged from -0.06 to 2.00, and values over Southeast Asia and off the coast near Sydney were the highest. The improved shipborne sky radiometer will contribute to a good understanding of the nature of aerosols over the ocean.

  9. Adaptive Spectral Doppler Estimation

    DEFF Research Database (Denmark)

    Gran, Fredrik; Jakobsson, Andreas; Jensen, Jørgen Arendt

    2009-01-01

    . The methods can also provide better quality of the estimated power spectral density (PSD) of the blood signal. Adaptive spectral estimation techniques are known to pro- vide good spectral resolution and contrast even when the ob- servation window is very short. The 2 adaptive techniques are tested......In this paper, 2 adaptive spectral estimation techniques are analyzed for spectral Doppler ultrasound. The purpose is to minimize the observation window needed to estimate the spectrogram to provide a better temporal resolution and gain more flexibility when designing the data acquisition sequence...... and compared with the averaged periodogram (Welch’s method). The blood power spectral capon (BPC) method is based on a standard minimum variance technique adapted to account for both averaging over slow-time and depth. The blood amplitude and phase estimation technique (BAPES) is based on finding a set...

  10. Simulating Visible/Infrared Imager Radiometer Suite Normalized Difference Vegetation Index Data Using Hyperion and MODIS

    Science.gov (United States)

    Ross, Kenton W.; Russell, Jeffrey; Ryan, Robert E.

    2006-01-01

    The success of MODIS (the Moderate Resolution Imaging Spectrometer) in creating unprecedented, timely, high-quality data for vegetation and other studies has created great anticipation for data from VIIRS (the Visible/Infrared Imager Radiometer Suite). VIIRS will be carried onboard the joint NASA/Department of Defense/National Oceanic and Atmospheric Administration NPP (NPOESS (National Polar-orbiting Operational Environmental Satellite System) Preparatory Project). Because the VIIRS instruments will have lower spatial resolution than the current MODIS instruments 400 m versus 250 m at nadir for the channels used to generate Normalized Difference Vegetation Index data, scientists need the answer to this question: how will the change in resolution affect vegetation studies? By using simulated VIIRS measurements, this question may be answered before the VIIRS instruments are deployed in space. Using simulated VIIRS products, the U.S. Department of Agriculture and other operational agencies can then modify their decision support systems appropriately in preparation for receipt of actual VIIRS data. VIIRS simulations and validations will be based on the ART (Application Research Toolbox), an integrated set of algorithms and models developed in MATLAB(Registerd TradeMark) that enables users to perform a suite of simulations and statistical trade studies on remote sensing systems. Specifically, the ART provides the capability to generate simulated multispectral image products, at various scales, from high spatial hyperspectral and/or multispectral image products. The ART uses acquired ( real ) or synthetic datasets, along with sensor specifications, to create simulated datasets. For existing multispectral sensor systems, the simulated data products are used for comparison, verification, and validation of the simulated system s actual products. VIIRS simulations will be performed using Hyperion and MODIS datasets. The hyperspectral and hyperspatial properties of Hyperion

  11. Diviner lunar radiometer gridded brightness temperatures from geodesic binning of modeled fields of view

    Science.gov (United States)

    Sefton-Nash, E.; Williams, J.-P.; Greenhagen, B. T.; Aye, K.-M.; Paige, D. A.

    2017-12-01

    An approach is presented to efficiently produce high quality gridded data records from the large, global point-based dataset returned by the Diviner Lunar Radiometer Experiment aboard NASA's Lunar Reconnaissance Orbiter. The need to minimize data volume and processing time in production of science-ready map products is increasingly important with the growth in data volume of planetary datasets. Diviner makes on average >1400 observations per second of radiance that is reflected and emitted from the lunar surface, using 189 detectors divided into 9 spectral channels. Data management and processing bottlenecks are amplified by modeling every observation as a probability distribution function over the field of view, which can increase the required processing time by 2-3 orders of magnitude. Geometric corrections, such as projection of data points onto a digital elevation model, are numerically intensive and therefore it is desirable to perform them only once. Our approach reduces bottlenecks through parallel binning and efficient storage of a pre-processed database of observations. Database construction is via subdivision of a geodesic icosahedral grid, with a spatial resolution that can be tailored to suit the field of view of the observing instrument. Global geodesic grids with high spatial resolution are normally impractically memory intensive. We therefore demonstrate a minimum storage and highly parallel method to bin very large numbers of data points onto such a grid. A database of the pre-processed and binned points is then used for production of mapped data products that is significantly faster than if unprocessed points were used. We explore quality controls in the production of gridded data records by conditional interpolation, allowed only where data density is sufficient. The resultant effects on the spatial continuity and uncertainty in maps of lunar brightness temperatures is illustrated. We identify four binning regimes based on trades between the

  12. Introduction to spectral theory

    CERN Document Server

    Levitan, B M

    1975-01-01

    This monograph is devoted to the spectral theory of the Sturm- Liouville operator and to the spectral theory of the Dirac system. In addition, some results are given for nth order ordinary differential operators. Those parts of this book which concern nth order operators can serve as simply an introduction to this domain, which at the present time has already had time to become very broad. For the convenience of the reader who is not familar with abstract spectral theory, the authors have inserted a chapter (Chapter 13) in which they discuss this theory, concisely and in the main without proofs, and indicate various connections with the spectral theory of differential operators.

  13. New improved algorithm for sky calibration of L-band radiometers JLBARA and ELBARA II

    KAUST Repository

    Dimitrov, Marin; Kostov, K. G.; Jonard, Franç ois; Jadoon, Khan; Schwank, Mike; Weihermü ller, Lutz; Hermes, Normen; Vanderborght, Jan P.; Vereecken, Harry

    2012-01-01

    We propose a new algorithm for sky calibration of the L-band radiometers JLBARA and ELBARA II, introducing the effective transmissivities of the instruments. The suggested approach was tested using experimental data obtained at the Selhausen test site, Germany. It was shown that for JLBARA the effective transmissivities depend strongly on the air temperature and decrease with increasing air temperature, while for ELBARA II such strong dependence was not observed. It was also shown that the effective transmissivities account for the antenna and feed cable loss effects, and for the variations of the radiometer gain due to air temperature changes. The new calibration algorithm reduces significantly the bias of brightness temperature estimates for both radiometers, especially for JLBARA. © 2012 IEEE.

  14. New improved algorithm for sky calibration of L-band radiometers JLBARA and ELBARA II

    KAUST Repository

    Dimitrov, Marin

    2012-03-01

    We propose a new algorithm for sky calibration of the L-band radiometers JLBARA and ELBARA II, introducing the effective transmissivities of the instruments. The suggested approach was tested using experimental data obtained at the Selhausen test site, Germany. It was shown that for JLBARA the effective transmissivities depend strongly on the air temperature and decrease with increasing air temperature, while for ELBARA II such strong dependence was not observed. It was also shown that the effective transmissivities account for the antenna and feed cable loss effects, and for the variations of the radiometer gain due to air temperature changes. The new calibration algorithm reduces significantly the bias of brightness temperature estimates for both radiometers, especially for JLBARA. © 2012 IEEE.

  15. Use of Electronic Hand-held Devices for Collection of Savannah River Site Environmental Data - 13329

    Energy Technology Data Exchange (ETDEWEB)

    Marberry, Hugh [SRNS Savannah River Site 730-4B Room 3043 Aiken, SC 29808 (United States); Moore, Winston [SRNS Savannah River Site 735B Room 116 Aiken, SC 29808 (United States)

    2013-07-01

    Savannah River Nuclear Solutions has begun using Xplore Tablet PC's to collect data in the field for soil samples, groundwater samples, air samples and round sheets at the Savannah River Site (SRS). EPA guidelines for groundwater sampling are incorporated into the application to ensure the sample technician follows the proper protocol. The sample technician is guided through the process for sampling and round sheet data collection by a series of menus and input boxes. Field measurements and well stabilization information are entered into the tablet for uploading into Environmental Restoration Data Management System (ERDMS). The process helps to eliminate input errors and provides data integrity. A soil sample technician has the ability to collect information about location of sample, field parameter, describe the soil sample, print bottle labels, and print chain of custody for the sample that they have collected. An air sample technician has the ability to provide flow, pressure, hours of operation, print bottle labels and chain of custody for samples they collect. Round sheets are collected using the information provided in the various procedures. The data are collected and uploaded into ERDMS. The equipment used is weather proof and hardened for the field use. Global Positioning System (GPS) capabilities are integrated into the applications to provide the location where samples were collected and to help sample technicians locate wells that are not visited often. (authors)

  16. OCT-based angiography in real time with hand-held probe

    Science.gov (United States)

    Gelikonov, Grigory V.; Moiseev, Alexander A.; Ksenofontov, Sergey Y.; Terpelov, Dmitry A.; Gelikonov, Valentine M.

    2018-03-01

    This work is dedicated to development of the OCT system capable to visualize blood vessel network for everyday clinical use. Following problems were solved during the development: compensation of specific natural tissue displacements, induced by contact scanning mode and physiological motion of patients (e.g. respiratory and cardiac motions) and on-line visualization of vessel net to provide the feedback for system operator.

  17. Perceiving the vertical distances of surfaces by means of a hand-held probe.

    Science.gov (United States)

    Chan, T C; Turvey, M T

    1991-05-01

    Nine experiments were conducted on the haptic capacity of people to perceive the distances of horizontal surfaces solely on the basis of mechanical stimulation resulting from contacting the surfaces with a vertically held rod. Participants touched target surfaces with rods inside a wooden cabinet and reported the perceived surface location with an indicator outside the cabinet. The target surface, rod, and the participant's hand were occluded, and the sound produced in exploration was muffled. Properties of the probe (length, mass, moment of inertia, center of mass, and shape) were manipulated, along with surface distance and the method and angle of probing. Results suggest that for the most common method of probing, namely, tapping, perceived vertical distance is specific to a particular relation among the rotational inertia of the probe, the distance of the point of contact with the surface from the probe's center of percussion, and the inclination at contact of the probe to the surface. They also suggest that the probe length and the distance probed are independently perceivable. The results were discussed in terms of information specificity versus percept-percept coupling and parallels between selective attention in haptic and visual perception.

  18. Poor correlation between intracranial pressure and intraocular pressure by hand-held tonometry

    Directory of Open Access Journals (Sweden)

    Golan S

    2013-06-01

    Full Text Available Shani Golan,1 Shimon Kurtz,1 Daphna Mezad-Koursh,1 Michael Waisbourd,1 Anat Kesler,1 Pinchas Halpern2 1Departments of Ophthalmology, Tel Aviv Sourasky Medical Center, affiliated with the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; 2Emergency Medicine, Tel Aviv Sourasky Medical Center, affiliated with the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel Purpose: The aim of this study is to provide data on the controversial issue of whether handheld measurements of intraocular pressure (IOP are capable of accurately predicting elevated intracranial pressure (ICP in patients undergoing lumbar puncture (LP. Methods: All patients over the age of 18 years who underwent an LP in the emergency or neurological departments at the Tel Aviv Medical center for any reason between October 2007 and July 2010 were eligible to participate in this prospective observational pilot study. IOP was measured with the Tono-Pen XL while patients were in the supine position before undergoing LP. ICP was measured in the lateral recumbent position. ICP and bilateral IOP were measured, and the mean and maximum values of IOP were calculated. The association between ICP and each one of the four IOP measures was evaluated by the Pearson correlation coefficient. Results: Twenty-four patients (mean age 37.8 ± 15.8 years, ten males and 14 females were enrolled. The reasons for their requiring an LP were headache (19/24 patients, evaluation for hemiparesis (2/24, cognitive deterioration (1/24, and seizures (2/24. Nine had elevated mean opening pressure (>20 cm H2O, six had an elevated mean IOP (>20 mmHg, and four of these six also had an elevated opening pressure. There was no significant correlation between the ICP measurements and any of the IOP measurements. Conclusion: Handheld ocular tonometry has poor sensitivity and specificity for the prediction of increased ICP and is not an effective tool for screening for ICP in the ED or in the neurology department. Keywords: ocular tonometry, Tono-Pen, IOP, intraocular pressure, ICP, intracranial pressure

  19. Preoperative distraction in children: hand-held videogames vs clown therapy

    Directory of Open Access Journals (Sweden)

    M. Messina

    2014-12-01

    Full Text Available Anxiety in children undergoing surgery is characterized by feelings of tension, apprehension, nervousness and fear which may manifest differently. Postoperative behavioural changes such as nocturnal enuresis, feeding disorders, apathy, and sleep disturbances may stem from postoperative anxiety. Some Authors pointed out that over 60% of children undergoing surgery are prone to developing behavioural alterations 2 weeks after surgery. Variables such as age, temperament and anxiety both in children and parents are considered predictors of such changes.1 Studies were published describing how psycho-behavioural interventions based on play, learning and entertainment in preparing children for surgery, may reduce preoperative anxiety. Clown-therapy is applied in the most important paediatric facilities and has proved to diminish children’s emotional distress and sufferance, as well as consumption of both analgesics and sedatives and to facilitate the achievement of therapeutic goals. The aim of our study was to evaluate the efficacy of clown-therapy during the child’s hospital stay, with a view to optimizing treatment and care, preventing behavioural alterations and enhancing the child’s overall life quality.

  20. Evaluation of hand-held ion-mobility explosives vapor detectors

    International Nuclear Information System (INIS)

    Burrows, T.A.; Thoma, P.J.

    1979-12-01

    Two types of ion-mobility detectors were evaluated in both laboratory and field tests. Laboratory test results show that these detectors are highly sensitive to dynamite and pistol powder and have good false-alarm agent rejection. Field tests of these two detectors revealed that they would detect dynamite and Ball-C-Propellent in free air. However, neither of the ion-mobility detectors would detect these explosives if the explosives were concealed

  1. An Evaluation of the Feasibility of Using Hand-Held Computers for Training.

    Science.gov (United States)

    1982-05-30

    approved. I FRANK E. GIUNTI F. A. NERONE Chief, Instructuinal Colonel, Infantry Development Division Director, Training Developments Institute...on electronic networks (PLATO) were initiated, and HHCs were borrowed and programmed. A number of Battelle experts were also consulted. Devices Noted...of a network . as an book. aide-memoire, a calculator, a word For outdoor use there is no processor, a financial planner and comparable product. From on

  2. Clinical assessment of hip strength using a hand-held dynamometer is reliable

    DEFF Research Database (Denmark)

    Thorborg, K; Petersen, J; Magnusson, S P

    2010-01-01

    Hip strength assessment plays an important role in the clinical examination of the hip and groin region. The primary aim of this study was to examine the absolute test-retest measurement variation concerning standardized strength assessments of hip abduction (ABD), adduction (ADD), external...... tests. No systematic differences were present. Standardized strength assessment procedures of hip ABD, ER, IR, FLEX, with test-retest measurement variation below 5%, hip ADD below 6% and hip EXT below 8%, make it possible to determine even small changes in hip strength at the individual level....

  3. 75 FR 32803 - Notice of Issuance of Final Determination Concerning a GTX Mobile+ Hand Held Computer

    Science.gov (United States)

    2010-06-09

    ... shall be published in the Federal Register within 60 days of the date the final determination is issued..., involved various scenarios pertaining to the assembly of a desktop computer in the U.S. and the Netherlands... finished desktop computers depending on the model included an additional floppy drive, CD ROM disk, and...

  4. Miniaturized hand held microwave interference scanning system for NDE of dielectric armor and armor systems

    International Nuclear Information System (INIS)

    Schmidt, Karl F.; Little, Jack R.; Ellingson, William A.; Meitzler, Thomas J.; Green, William

    2011-01-01

    Inspection of ceramic-based armor has advanced through development of a microwave-based, portable, non-contact NDE system. Recently, this system was miniaturized and made wireless for maximum utility in field applications. The electronic components and functionality of the laboratory system are retained, with alternative means of position input for creation of scan images. Validation of the detection capability was recently demonstrated using specially fabricated surrogates and ballistic impact-damaged specimens. The microwave data results have been compared to data from laboratory-based microwave interferometry systems and digital x-ray imaging. The microwave interference scanning has been shown to reliably detect cracks, laminar features and material property variations. The authors present details of the system operation, descriptions of the test samples used and recent results obtained.

  5. In vivo quantitative evaluation of tooth color with hand-held colorimeter and custom template.

    Science.gov (United States)

    Shimada, Kazuki; Kakehashi, Yoshiyuki; Matsumura, Hideo; Tanoue, Naomi

    2004-04-01

    This article presents a technique for quantitatively evaluating the color of teeth, as well as color change in restorations and tooth surfaces. Through use of a custom template made of a thermoplastic polymer and a dental colorimeter, tooth surface color can be recorded periodically at the same location intraorally.

  6. Use of Electronic Hand-held Devices for Collection of Savannah River Site Environmental Data - 13329

    International Nuclear Information System (INIS)

    Marberry, Hugh; Moore, Winston

    2013-01-01

    Savannah River Nuclear Solutions has begun using Xplore Tablet PC's to collect data in the field for soil samples, groundwater samples, air samples and round sheets at the Savannah River Site (SRS). EPA guidelines for groundwater sampling are incorporated into the application to ensure the sample technician follows the proper protocol. The sample technician is guided through the process for sampling and round sheet data collection by a series of menus and input boxes. Field measurements and well stabilization information are entered into the tablet for uploading into Environmental Restoration Data Management System (ERDMS). The process helps to eliminate input errors and provides data integrity. A soil sample technician has the ability to collect information about location of sample, field parameter, describe the soil sample, print bottle labels, and print chain of custody for the sample that they have collected. An air sample technician has the ability to provide flow, pressure, hours of operation, print bottle labels and chain of custody for samples they collect. Round sheets are collected using the information provided in the various procedures. The data are collected and uploaded into ERDMS. The equipment used is weather proof and hardened for the field use. Global Positioning System (GPS) capabilities are integrated into the applications to provide the location where samples were collected and to help sample technicians locate wells that are not visited often. (authors)

  7. 77 FR 73354 - Safety Standard for Hand-Held Infant Carriers

    Science.gov (United States)

    2012-12-10

    .... Edwards, Project Manager, Directorate for Engineering Sciences, U.S. Consumer Product Safety Commission, 5..., allergic reactions and near- choking episodes are the most common injuries reported in the remaining 58... modification of the ASTM standard to address the requirements for flammability, surface chemicals, cords...

  8. Panasonic HR-1800 Hand-Held Computer Solutions to Composite Materials Formulas.

    Science.gov (United States)

    1983-09-01

    TR-83-4093 PROGRAM LISTING (Cont’d) I, : E-6 :PE*u3 D RINT 3 =U4---4*U3 gtr -BINf X𔃾)=U5-C4§U3 GS fQ :T SEXT *lJ 3 54A@ ;OSUB 6)i6’S2*U2J ,’-54 PLA... SEXT * 3’E6 ":W=X(ue) E:=E1*A(1i:E2:- * * :628800)E=6. ~.-- (33B4*A~ )2A QPmI 5 39 a@ G$=" T r4EH 310 1APUT p~~4 ~2’ -;C SUB 3800 ŗUCK!:4G (T’...u (?00

  9. Edgewood Biosensors Test Bed Hand-held and Man-Portable Edition

    Science.gov (United States)

    2013-09-01

    CORPORATION, INC. Gunpowder, MD 21010-0068 Evan Skowronski TMG BIOSCIENCES Incline Village, NV 89451 September 2013 Approved for public release...Emanuel, Peter (ECBC); Rivers, Bryan; Schaffer, Eric (SAIC); and Skowronski, Evan ( TMG Biosciences) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK...21010-0068 TMG Biosciences, 774 Mays Blvd. #10-455, Incline Village, NV 89451 8. PERFORMING ORGANIZATION REPORT NUMBER ECBC-TR-1201 9

  10. Transforming an Introductory Linear Algebra Course with a TI-92 Hand-Held Computer.

    Science.gov (United States)

    Quesada, Antonio R.

    2003-01-01

    Describes how the introduction of the TI-92 transformed a traditional first semester linear algebra course into a matrix-oriented course that emphasized conceptual understanding, relevant applications, and numerical issues. Indicates an increase in students' overall performance as they found the calculator very useful, believed it helped them…

  11. An improved hand-held four-detector gamma-probe for radioassisted oncological surgery

    CERN Document Server

    Dusi, W; Bollini, D; Moroni, C; Ricard, M

    2000-01-01

    The performance of an improved intraoperative gamma-probe for radioassisted oncological surgery is presented and discussed. The probe is based on a square array of four 5x5 mm sup 2 coplanar CdTe room temperature semiconductor detectors and each detector has an independent read out electronic chain, allowing an original handling of the signal. Therefore, the search for gamma-emission hot points may be carried out in two different, independent ways: (1) Finding out the position of the probe corresponding to the maximum value of the total counting rate, on the basis of a trial and error procedure (typical for the conventional probe; (2) Finding out the position of the probe where both the differences between the counting rate performed by orthogonal, adjacent halves of the array vanish (differential method). This makes the new probe sensitive to the bidimensional gradient of the gamma-ray flux, measured on the scanned plane. Furthermore, the algebraic sign of the difference indicates in which direction the prob...

  12. The use of stereolithographic hand held models for evaluation of congenital anomalies of the great arteries.

    Science.gov (United States)

    Vranicar, Mark; Gregory, William; Douglas, William I; Di Sessa, Peter; Di Sessa, Thomas G

    2008-01-01

    Imaging anomalies of the great vessels has traditionally been accomplished using conventional biplane modalities as well as three-dimensional (3D) video displays. Our aim was to review the use of stereolithography to create 3D models to assess coarctation of the aorta and vascular rings. Twelve patients had high-resolution CT scans to evaluate anomalies of the great arteries (coarctation: 9, vascular ring: 3). Ages were 19 days to 29 years and weights were 3.3 to 139 kg. Digital dicom data from each scan were converted by a commercially available software package into a 3D digital image. The area of interest was selected and the image was exported to a 3D stereolithographic printer to create a 3D model. The models were then evaluated and the results compared to catheterization and surgical findings. All models accurately displayed the pathology investigated. All 3 of the vascular ring models correlated with surgical findings (double arch: 2, pulmonary sling: 1). Models of aortic coarctation allowed clear depictions of discrete narrowing as well as arch hypoplasia and tortuosity. Stereolithography can create realistic 3D models that accurately display aortic pathology and add important additional information, which may have implications regarding surgical and transcatheter interventions and may also be useful teaching tools for parents and students.

  13. Preoperative distraction in children: hand-held videogames vs clown therapy.

    Science.gov (United States)

    Messina, M; Molinaro, F; Meucci, D; Angotti, R; Giuntini, L; Cerchia, E; Bulotta, A L; Brandigi, E

    2014-12-30

    Anxiety in children undergoing surgery is characterized by feelings of tension, apprehension, nervousness and fear which may manifest differently. Postoperative behavioural changes such as nocturnal enuresis, feeding disorders, apathy, and sleep disturbances may stem from postoperative anxiety. Some Authors pointed out that over 60% of children undergoing surgery are prone to developing behavioural alterations 2 weeks after surgery. Variables such as age, temperament and anxiety both in children and parents are considered predictors of such changes.1 Studies were published describing how psycho-behavioural interventions based on play, learning and entertainment in preparing children for surgery, may reduce preoperative anxiety. Clown-therapy is applied in the most important paediatric facilities and has proved to diminish children's emotional distress and sufferance, as well as consumption of both analgesics and sedatives and to facilitate the achievement of therapeutic goals. The aim of our study was to evaluate the efficacy of clown-therapy during the child's hospital stay, with a view to optimizing treatment and care, preventing behavioural alterations and enhancing the child's overall life quality.

  14. Advanced sampling techniques for hand-held FT-IR instrumentation

    Science.gov (United States)

    Arnó, Josep; Frunzi, Michael; Weber, Chris; Levy, Dustin

    2013-05-01

    FT-IR spectroscopy is the technology of choice to identify solid and liquid phase unknown samples. The challenging ConOps in emergency response and military field applications require a significant redesign of the stationary FT-IR bench-top instruments typically used in laboratories. Specifically, field portable units require high levels of resistance against mechanical shock and chemical attack, ease of use in restrictive gear, extreme reliability, quick and easy interpretation of results, and reduced size. In the last 20 years, FT-IR instruments have been re-engineered to fit in small suitcases for field portable use and recently further miniaturized for handheld operation. This article introduces the HazMatID™ Elite, a FT-IR instrument designed to balance the portability advantages of a handheld device with the performance challenges associated with miniaturization. In this paper, special focus will be given to the HazMatID Elite's sampling interfaces optimized to collect and interrogate different types of samples: accumulated material using the on-board ATR press, dispersed powders using the ClearSampler™ tool, and the touch-to-sample sensor for direct liquid sampling. The application of the novel sample swipe accessory (ClearSampler) to collect material from surfaces will be discussed in some detail. The accessory was tested and evaluated for the detection of explosive residues before and after detonation. Experimental results derived from these investigations will be described in an effort to outline the advantages of this technology over existing sampling methods.

  15. Hand-held, mechanically cooled, radiation detection system for gamma-ray spectroscopy

    Science.gov (United States)

    Burks, Morgan Thomas; Eckels, Joel Del

    2010-06-08

    In one embodiment, a radiation detection system is provided including a radiation detector and a first enclosure encapsulating the radiation detector, the first enclosure including a low-emissivity infra-red (IR) reflective coating used to thermally isolate the radiation detector. Additionally, a second enclosure encapsulating the first enclosure is included, the first enclosure being suspension mounted to the second enclosure. Further, a cooler capable of cooling the radiation detector is included. Still yet, a first cooling interface positioned on the second enclosure is included for coupling the cooler and the first enclosure. Furthermore, a second cooling interface positioned on the second enclosure and capable of coupling the first enclosure to a cooler separate from the radiation detection system is included. Other embodiments are also presented.

  16. A hand-held row-column addressed CMUT probe with integrated electronics for volumetric imaging

    DEFF Research Database (Denmark)

    Engholm, Mathias; Christiansen, Thomas Lehrmann; Beers, Christopher

    2015-01-01

    A 3 MHz, λ / 2-pitch 62+62 channel row-column addressed 2-D CMUT array designed to be mounted in a probe handle and connected to a commercial BK Medical scanner for real-time volumetric imaging is presented. It is mounted and wire-bonded on a flexible PCB, which is connected to two rigid PCBs...

  17. Measurement of Visual Reaction Times Using Hand-held Mobile Devices

    Science.gov (United States)

    Mulligan, Jeffrey B.; Arsintescu, Lucia; Flynn-Evans, Erin

    2015-01-01

    Modern mobile devices provide a convenient platform for collecting research data in the field. But,because the working of these devices is often cloaked behind multiple layers of proprietary system software, it can bedifficult to assess the accuracy of the data they produce, particularly in the case of timing. We have been collecting datain a simple visual reaction time experiment, as part of a fatigue testing protocol known as the Psychomotor Vigilance Test (PVT). In this protocol, subjects run a 5-minute block consisting of a sequence of trials in which a visual stimulus appears after an unpredictable variable delay. The subject is required to tap the screen as soon as possible after the appearance of the stimulus. In order to validate the reaction times reported by our program, we had subjects perform the task while a high-speed video camera recorded both the display screen, and a side view of the finger (observed in a mirror). Simple image-processing methods were applied to determine the frames in which the stimulus appeared and disappeared, and in which the finger made and broke contact with the screen. The results demonstrate a systematic delay between the initial contact by the finger and the detection of the touch by the software, having a value of 80 +- 20 milliseconds.

  18. Study of Hand-Held Fire Extinguishers Aboard Civil Aviation Aircraft.

    Science.gov (United States)

    1982-06-01

    cyanide (HCN), oxides of nitrogen (NO ), ammonia (NH3 ), hydrogen suifide (H 2S), phosgene (COC12 ), and many other compounds. * . "From fires in...that the effective volume is up to 300 times that of the stored volume. Foam is an effective scrubber for fumes and smoke. Foam blankets over

  19. Performance evaluation of a hand-held, semiconductor (CdZnTe)-based gamma camera

    CERN Document Server

    Abe, A; Lee, J; Oka, T; Shizukuishi, K; Kikuchi, T; Inoue, T; Jimbo, M; Ryuo, H; Bickel, C

    2003-01-01

    We have designed and developed a small field of view gamma camera, the eZ SCOPE, based on use of a CdZnTe semiconductor. This device utilises proprietary signal processing technology and an interface to a computer-based imaging system. The purpose of this study was to evaluate the performance of the eZ scope in comparison with currently employed gamma camera technology. The detector is a single wafer of 5-mm-thick CdZnTe that is divided into a 16 x 16 array (256 pixels). The sensitive area of the detector is a square of dimension 3.2 cm. Two parallel-hole collimators are provided with the system and have a matching (256 hole) pattern to the CdZnTe detector array: a low-energy, high-resolution parallel-hole (LEHR) collimator fabricated of lead and a low-energy, high-sensitivity parallel-hole (LEHS) collimator fabricated of tungsten. Performance measurements and the data analysis were done according to the procedures of the NEMA standard. We also studied the long-term stability of the system with continuous use...

  20. Inter- and intrarater reliability of goniometry and hand held dynamometry for patients with subacromial impingement syndrome.

    Science.gov (United States)

    Fieseler, Georg; Laudner, Kevin G; Irlenbusch, Lars; Meyer, Henrike; Schulze, Stephan; Delank, Karl-Stefan; Hermassi, Souhail; Bartels, Thomas; Schwesig, René

    2017-12-01

    The purpose of this study was to examine the intra- and interrater reliability of measuring shoulder range of motion (ROM) and strength among patients diagnosed with subacromial impingement syndrome (SAIS). Twenty-five patients (14 female patients; mean age, 60.4± 7.84 years) diagnosed with SAIS were assessed to determine the intrarater reliability for glenohumeral ROM. Twenty-five patients (16 female patients; mean age, 60.4± 7.80 years) and 76 asymptomatic volunteers (52 female volunteers; mean age, 29.4± 14.1 years) were assessed for interrater reliability. Dependent variables were active shoulder ROM and isometric strength. Intrarater reliability was fair-to-excellent for the SAIS patients (intraclass correlation coefficient [ICC], 0.52-0.97; standard error of measurement [SEM], 4.4°-9.9° N; coefficient of variation [CV], 7.1%-44.9%). Based on the ICC, 11 of 12 parameters (92%) displayed an excellent reliability (ICC> 0.75). The interrater reliability showed fair-to-excellent results (SAIS patients: ICC, 0.13-0.98; SEM, 2.3°-8.8°; CV, 3.6%-37.0%; controls: ICC, 0.11-0.96; SEM, 3.0°-35.4°; CV, 5.6%-26.4%). In accordance with the intrarater reliability, glenohumeral adduction ROM was the only parameter with an ICC below 0.75 for both samples. Painful shoulder ROM in the SAIS patients showed no influence on the quality of reliability for measurement. Therefore, these protocols should be considered reliable assessment techniques in the prevention, diagnosis, and treatment of painful shoulder conditions such as SAIS.

  1. Real-time Identification System using Mobile Hand-held Devices: Mobile Biometrics Evaluation Framework

    Science.gov (United States)

    2014-04-01

    test server, transmit five test cases over both WIFI and 3G , and receive accurate results. The second Study output, the Mobile Biometrics Evaluation...wired (USB), near field (Bluetooth), wireless (802.11) and cellular ( 2G / 3G ) connectivity. Satellite (BGAN) devices have been deployed, in conjunction...Wireless Connectivity: 802.11b, 802.11g, Bluetooth Cellular Connectivity: GSM [ 2G ], UMTS [ 3G ] Internal RAM (GB): 128 Internal Storage (GB): 128

  2. Radiation budget studies using collocated observations from advanced Very High Resolution Radiometer, High-Resolution Infrared Sounder/2, and Earth Radiation Budget Experiment instruments

    Science.gov (United States)

    Ackerman, Steven A.; Frey, Richard A.; Smith, William L.

    1992-01-01

    Collocated observations from the Advanced Very High Resolution Radiometer (AVHRR), High-Resolution Infrared Sounder/2 (HIRS/2), and Earth Radiation Budget Experiment (ERBE) instruments onboard the NOAA 9 satellite are combined to describe the broadband and spectral radiative properties of the earth-atmosphere system. Broadband radiative properties are determined from the ERBE observations, while spectral properties are determined from the HIRS/2 and AVHRR observations. The presence of clouds, their areal coverage, and cloud top pressure are determined from a combination of the HIRS/2 and the AVHRR observations. The CO2 slicing method is applied to the HIRS/2 to determine the presence of upper level clouds and their effective emissivity. The AVHRR data collocated within the HIRS/2 field of view are utilized to determine the uniformity of the scene and retrieve sea surface temperature. Changes in the top of the atmosphere longwave and shortwave radiative energy budgets, and the spectral distribution of longwave radiation are presented as a function of cloud amount and cloud top pressure. The radiative characteristics of clear sky conditions over oceans are presented as a function of sea surface temperature and atmospheric water vapor structure.

  3. Description and Performance of an L-Band Radiometer with Digital Beamforming

    Directory of Open Access Journals (Sweden)

    Juan F. Marchan-Hernandez

    2010-12-01

    Full Text Available This paper presents the description and performance tests of an L-band microwave radiometer with Digital Beamforming (DBF, developed for the Passive Advanced Unit (PAU for ocean monitoring project. PAU is an instrument that combines, in a single receiver and without time multiplexing, a microwave radiometer at L-band (PAU-RAD and a GPS-reflectometer (PAU-GNSS-R. This paper focuses on the PAU‑RAD beamformer’s first results, analyzing the hardware and software required for the developed prototype. Finally, it discusses the first results measured in the Universitat Politècnica de Catalunya (UPC anechoic chamber.

  4. Development of an improved Newtonian total radiometer, its evaluation and calibration

    International Nuclear Information System (INIS)

    Castrejon G, R.; Morales, A.

    1998-01-01

    Measuring of radiant energy by optical non intrusive means is an important topic of research in many areas of science and technology. Precise evaluation of thermal energy emitted by hot bodies leads to a better understanding of the energy interchange phenomena between the body and its surroundings. To this end, a wide spectrum optical radiometer was developed. In this article we describe the construction and evaluation of this instrument and the physical principles involved in its design and operation. Among other advantages, the linear response of the instrument allows easily a precise calibration. Additionally, we give a procedure to obtain a known source of radiation that was used to calibrate the radiometer. (Author)

  5. The Along Track Scanning Radiometer (ATSR) - Orbital performance and future developments

    Science.gov (United States)

    Sandford, M. C. W.; Edwards, T.; Mutlow, C. T.; Delderfield, J.; Llewellyn-Jones, D. T.

    1992-08-01

    The Along-Track Scanning Radiometer (ATSR), a new kind of infrared radiometer which is intended to make sea surface temperature measurements with an absolute accuracy of +/- 0.5 K averaged over cells of 0.5 deg in latitude, is discussed. The ATSR employs four detectors centered at 12, 11, 3.7, and 1.6 microns. The noise performance thermal performance, and Stirling cycle cooler performance of the ATSR on ERS-1 are examined along with 3.7 micron channel results. The calibration, structure, and data handling of the ATSRs planned for ERS-2 and for the POEM mission are examined.

  6. On Longitudinal Spectral Coherence

    DEFF Research Database (Denmark)

    Kristensen, Leif

    1979-01-01

    It is demonstrated that the longitudinal spectral coherence differs significantly from the transversal spectral coherence in its dependence on displacement and frequency. An expression for the longitudinal coherence is derived and it is shown how the scale of turbulence, the displacement between ...... observation sites and the turbulence intensity influence the results. The limitations of the theory are discussed....

  7. Development of a High-Stability Microstrip-based L-band Radiometer for Ocean Salinity Measurements

    Science.gov (United States)

    Pellerano, Fernando A.; Horgan, Kevin A.; Wilson, William J.; Tanner, Alan B.

    2004-01-01

    The development of a microstrip-based L-band Dicke radiometer with the long-term stability required for future ocean salinity measurements to an accuracy of 0.1 psu is presented. This measurement requires the L-band radiometers to have calibration stabilities of less than or equal to 0.05 K over 2 days. This research has focused on determining the optimum radiometer requirements and configuration to achieve this objective. System configuration and component performance have been evaluated with radiometer test beds at both JPL and GSFC. The GSFC testbed uses a cryogenic chamber that allows long-term characterization at radiometric temperatures in the range of 70 - 120 K. The research has addressed several areas including component characterization as a function of temperature and DC bias, system linearity, optimum noise diode injection calibration, and precision temperature control of components. A breadboard radiometer, utilizing microstrip-based technologies, has been built to demonstrate this long-term stability.

  8. Estimation of spectral kurtosis

    Science.gov (United States)

    Sutawanir

    2017-03-01

    Rolling bearings are the most important elements in rotating machinery. Bearing frequently fall out of service for various reasons: heavy loads, unsuitable lubrications, ineffective sealing. Bearing faults may cause a decrease in performance. Analysis of bearing vibration signals has attracted attention in the field of monitoring and fault diagnosis. Bearing vibration signals give rich information for early detection of bearing failures. Spectral kurtosis, SK, is a parameter in frequency domain indicating how the impulsiveness of a signal varies with frequency. Faults in rolling bearings give rise to a series of short impulse responses as the rolling elements strike faults, SK potentially useful for determining frequency bands dominated by bearing fault signals. SK can provide a measure of the distance of the analyzed bearings from a healthy one. SK provides additional information given by the power spectral density (psd). This paper aims to explore the estimation of spectral kurtosis using short time Fourier transform known as spectrogram. The estimation of SK is similar to the estimation of psd. The estimation falls in model-free estimation and plug-in estimator. Some numerical studies using simulations are discussed to support the methodology. Spectral kurtosis of some stationary signals are analytically obtained and used in simulation study. Kurtosis of time domain has been a popular tool for detecting non-normality. Spectral kurtosis is an extension of kurtosis in frequency domain. The relationship between time domain and frequency domain analysis is establish through power spectrum-autocovariance Fourier transform. Fourier transform is the main tool for estimation in frequency domain. The power spectral density is estimated through periodogram. In this paper, the short time Fourier transform of the spectral kurtosis is reviewed, a bearing fault (inner ring and outer ring) is simulated. The bearing response, power spectrum, and spectral kurtosis are plotted to

  9. On-board digital RFI and polarimetry processor for future spaceborne radiometer systems

    DEFF Research Database (Denmark)

    Skou, Niels; Kristensen, Steen Savstrup; Ruokokoski, T.

    2012-01-01

    Man-made Radio Frequency Interference (RFI) is an increasingly threatening problem for passive microwave radiometry from space. The problem is presently very evident in L-band data from SMOS, but it is realized that it is already now a problem at other traditional radiometer bands at C, X, and Ku...

  10. Inspection of feasible calibration conditions for UV radiometer detectors with the KI/KIO3 actinometer.

    Science.gov (United States)

    Qiang, Zhimin; Li, Wentao; Li, Mengkai; Bolton, James R; Qu, Jiuhui

    2015-01-01

    UV radiometers are widely employed for irradiance measurements, but their periodical calibrations not only induce an extra cost but also are time-consuming. In this study, the KI/KIO3 actinometer was applied to calibrate UV radiometer detectors at 254 nm with a quasi-collimated beam apparatus equipped with a low-pressure UV lamp, and feasible calibration conditions were identified. Results indicate that a washer constraining the UV light was indispensable, while the size (10 or 50 mL) of a beaker containing the actinometer solution had little influence when a proper washer was used. The absorption or reflection of UV light by the internal beaker wall led to an underestimation or overestimation of the irradiance determined by the KI/KIO3 actinometer, respectively. The proper range of the washer internal diameter could be obtained via mathematical analysis. A radiometer with a longer service time showed a greater calibration factor. To minimize the interference from the inner wall reflection of the collimating tube, calibrations should be conducted at positions far enough away from the tube bottom. This study demonstrates that after the feasible calibration conditions are identified, the KI/KIO3 actinometer can be applied readily to calibrate UV radiometer detectors at 254 nm. © 2014 The American Society of Photobiology.

  11. Polarimetric Signatures from a Crop Covered Land Surface Measured by an L-band Polarimetric Radiometer

    DEFF Research Database (Denmark)

    Søbjærg, Sten Schmidl; Skou, Niels

    2003-01-01

    This paper describes preliminary results from field measurements of polarimetric azimuth signatures with the EMIRAD L-band polarimetric radiometer, performed over a land test site at the Institut National de la Recherche Agronomique in Avignon, France. Scans of 180 degrees in azimuth were carried...

  12. Design of a rocket-borne radiometer for stratospheric ozone measurements

    International Nuclear Information System (INIS)

    Barnes, R.A.; Simeth, P.G.

    1989-01-01

    A four-filter ultraviolet radiometer for measuring stratospheric ozone is described. The payload is launched aboard a Super-Loki rocket to an apogee of 70 km. The instrument measures the solar ultraviolet irradiance over its filter wavelengths as it descends on a parachute. The amount of ozone in the path between the radiometer and the sun is calculated from the attenuation of solar flux using the Beer-Lambert law. Radar at the launch site measures the height of the instrument throughout its flight. The fundamental ozone value measured by the ROCOZ-A radiometer is the vertical ozone overburden as a function of geometric altitude. Ozone measurements are obtained for altitudes from 55 to 20 km, extending well above the altitude range of balloon-borne ozone-measuring instruments. The optics and electronics in the radiometer have been designed within relatively severe size and weight limitations imposed by the launch vehicle. The electronics in the improved rocket ozonesonde (ROCOZ-A) provide essentially drift-free outputs throughout 40-min ozone soundings at stratospheric temperatures. The modest cost of the payload precludes recovery and makes the instrument a versatile tool compared to larger ozonesondes

  13. L-Band Radiometers Measuring Salinity From Space: Atmospheric Propagation Effects

    DEFF Research Database (Denmark)

    Skou, Niels; Hofman-Bang, Dorthe

    2005-01-01

    Microwave radiometers can measure sea surface salinity from space using L-band frequencies around 1.4 GHz. However, requirements to the accuracy of the measurements, in order to be satisfactory for the user, are so stringent that the influence of the intervening atmosphere cannot be neglected...

  14. Insolation measurements with a portable CuS-CdS radiometer

    Science.gov (United States)

    Windawi, H. M.

    1976-01-01

    Solar radiation measurements were carried out with a portable Cu2S-Cds radiometer. The measurements were found to be accurate to better than 5% (better than 3% when sophisticated metering is employed). Calibration to an Eppley precision pyranometer is discussed.

  15. The Impact of Indoor and Outdoor Radiometer Calibration on Solar Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Habte, Aron; Sengupta, Manajit; Andreas, Afshin; Reda, Ibrahim; Robinson, Justin

    2016-06-02

    This study addresses the effect of calibration methodologies on calibration responsivities and the resulting impact on radiometric measurements. The calibration responsivities used in this study are provided by NREL's broadband outdoor radiometer calibration (BORCAL) and a few prominent manufacturers. The BORCAL method provides outdoor calibration responsivity of pyranometers and pyrheliometers at a 45 degree solar zenith angle and responsivity as a function of solar zenith angle determined by clear-sky comparisons to reference irradiance. The BORCAL method also employs a thermal offset correction to the calibration responsivity of single-black thermopile detectors used in pyranometers. Indoor calibrations of radiometers by their manufacturers are performed using a stable artificial light source in a side-by-side comparison of the test radiometer under calibration to a reference radiometer of the same type. These different methods of calibration demonstrated 1percent to 2 percent differences in solar irradiance measurement. Analyzing these values will ultimately enable a reduction in radiometric measurement uncertainties and assist in developing consensus on a standard for calibration.

  16. Hybrid PSO-ASVR-based method for data fitting in the calibration of infrared radiometer

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Sen; Li, Chengwei, E-mail: heikuanghit@163.com [School of Electrical Engineering and Automation, Harbin Institute of Technology, Harbin 150001 (China)

    2016-06-15

    The present paper describes a hybrid particle swarm optimization-adaptive support vector regression (PSO-ASVR)-based method for data fitting in the calibration of infrared radiometer. The proposed hybrid PSO-ASVR-based method is based on PSO in combination with Adaptive Processing and Support Vector Regression (SVR). The optimization technique involves setting parameters in the ASVR fitting procedure, which significantly improves the fitting accuracy. However, its use in the calibration of infrared radiometer has not yet been widely explored. Bearing this in mind, the PSO-ASVR-based method, which is based on the statistical learning theory, is successfully used here to get the relationship between the radiation of a standard source and the response of an infrared radiometer. Main advantages of this method are the flexible adjustment mechanism in data processing and the optimization mechanism in a kernel parameter setting of SVR. Numerical examples and applications to the calibration of infrared radiometer are performed to verify the performance of PSO-ASVR-based method compared to conventional data fitting methods.

  17. An RFI Detection Algorithm for Microwave Radiometers Using Sparse Component Analysis

    Science.gov (United States)

    Mohammed-Tano, Priscilla N.; Korde-Patel, Asmita; Gholian, Armen; Piepmeier, Jeffrey R.; Schoenwald, Adam; Bradley, Damon

    2017-01-01

    Radio Frequency Interference (RFI) is a threat to passive microwave measurements and if undetected, can corrupt science retrievals. The sparse component analysis (SCA) for blind source separation has been investigated to detect RFI in microwave radiometer data. Various techniques using SCA have been simulated to determine detection performance with continuous wave (CW) RFI.

  18. Mapping of the DOME-C area in Antarctica by an airborne L-band radiometer

    DEFF Research Database (Denmark)

    Skou, Niels; Kristensen, Steen Savstrup; Søbjærg, Sten Schmidl

    2014-01-01

    A 350 × 350 km area near the Concordia station on the high plateau of Dome C in Antarctica has been mapped by an airborne L-band radiometer system. The area was expected to display a rather uniform brightness temperature close to the yearly mean temperature — well suited for calibration checks...

  19. Airborne L-band radiometer mapping of the dome-C area in Antarctica

    DEFF Research Database (Denmark)

    Skou, Niels; Kristensen, Steen Savstrup; Søbjærg, Sten Schmidl

    2015-01-01

    A 350 km × 350 km area near the Concordia station on the high plateau of Dome-C in Antarctica has been mapped by an airborne L-band radiometer system. The area was expected to display a rather uniform brightness temperature (TB) close to the yearly mean temperature-well suited for calibration...

  20. InP HEMT Integrated Circuits for Submillimeter Wave Radiometers in Earth Remote Sensing

    Science.gov (United States)

    Deal, William R.; Chattopadhyay, Goutam

    2012-01-01

    The operating frequency of InP integrated circuits has pushed well into the Submillimeter Wave frequency band, with amplification reported as high as 670 GHz. This paper provides an overview of current performance and potential application of InP HEMT to Submillimeter Wave radiometers for earth remote sensing.

  1. Validation of multi-channel scanning microwave radiometer on-board Oceansat-1

    Digital Repository Service at National Institute of Oceanography (India)

    Muraleedharan, P.M.; Pankajakshan, T.; Harikrishnan, M.

    Sea surface temperature (SST), sea surface wind speed (WS) and columnar water vapour (WV) derived from Multi-frequency Scanning Microwave Radiometer (MSMR) sensor on-board IRS-P4 (Oceansat-1) were validated against the in situ measurements from ship...

  2. Thermal, Thermophysical, and Compositional Properties of the Moon Revealed by the Diviner Lunar Radiometer

    Science.gov (United States)

    Greenhagen, B. T.; Paige, D. A.

    2012-01-01

    The Diviner Lunar Radiometer is the first multispectral thermal instrument to globally map the surface of the Moon. After over three years in operation, this unprecedented dataset has revealed the extreme nature of the Moon's thermal environment, thermophysical properties, and surface composition.

  3. Ultra-portable field transfer radiometer for vicarious calibration of earth imaging sensors

    Science.gov (United States)

    Thome, Kurtis; Wenny, Brian; Anderson, Nikolaus; McCorkel, Joel; Czapla-Myers, Jeffrey; Biggar, Stuart

    2018-06-01

    A small portable transfer radiometer has been developed as part of an effort to ensure the quality of upwelling radiance from test sites used for vicarious calibration in the solar reflective. The test sites are used to predict top-of-atmosphere reflectance relying on ground-based measurements of the atmosphere and surface. The portable transfer radiometer is designed for one-person operation for on-site field calibration of instrumentation used to determine ground-leaving radiance. The current work describes the detector- and source-based radiometric calibration of the transfer radiometer highlighting the expected accuracy and SI-traceability. The results indicate differences between the detector-based and source-based results greater than the combined uncertainties of the approaches. Results from recent field deployments of the transfer radiometer using a solar radiation based calibration agree with the source-based laboratory calibration within the combined uncertainties of the methods. The detector-based results show a significant difference to the solar-based calibration. The source-based calibration is used as the basis for a radiance-based calibration of the Landsat-8 Operational Land Imager that agrees with the OLI calibration to within the uncertainties of the methods.

  4. Soil Moisture Active/Passive (SMAP) Radiometer Subband Calibration and Calibration Drift

    Science.gov (United States)

    Peng, Jinzheng; Piepmeier, Jeffrey R.; De Amici, Giovanni; Mohammed, Priscilla

    2016-01-01

    The SMAP is one of four first-tier missions recommended by the US National Research Council's Committee on Earth Science and Applications from Space (Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond, Space Studies Board, National Academies Press, 2007)]. The observatory was launched on Jan 31, 2015. The goal of the SMAP is to measure the global soil moisture and freeze/thaw from space. The L-band radiometer is the passive portion of the spaceborne instrument. It measures all four Stokes antenna temperatures and outputs counts. The Level 1B Brightness Temperature (L1B_TB) science algorithm converts radiometer counts to the Earths surface brightness temperature. The results are reported in the radiometer level 1B data product together with the calibrated antenna temperature (TA) and all of the corrections to the unwanted sources contribution. The calibrated L1B data product are required to satisfy the overall radiometer error budget of 1.3 K needed to meet the soil moisture requirement of 0.04 volumetric fraction uncertainty and the calibration drift requirement of no larger than 0.4 K per month.

  5. Soil Moisture Active Passive (SMAP) Radiometer Subband Calibration and Calibration Drift

    Science.gov (United States)

    Peng, Jinzheng; Piepmeier, Jeffrey R.; De Amici, Giovanni; Mohammed, Priscilla N.

    2016-01-01

    The SMAP is one of four first-tier missions recommended by the US National Research Council's Committee on Earth Science and Applications from Space (Earth Science and Applications from Space: National Imperatives for the Next Decade and Beyond, Space Studies Board, National Academies Press, 2007). The observatory was launched on Jan 31, 2015. The goal of the SMAP is to measure the global soil moisture and freeze/thaw from space. The L-band radiometer is the passive portion of the spaceborne instrument. It measures all four Stokes antenna temperatures and outputs counts. The Level 1B Brightness Temperature (L1B_TB) science algorithm converts radiometer counts to the Earths surface brightness temperature. The results are reported in the radiometer level 1B data product together with the calibrated antenna temperature (TA) and all of the corrections to the unwanted sources contribution. The calibrated L1B data product are required to satisfy the overall radiometer error budget of 1.3 K needed to meet the soil moisture requirement of 0.04 volumetric fraction uncertainty and the calibration drift requirement of no larger than 0.4 K per month.

  6. Spectrally accurate contour dynamics

    International Nuclear Information System (INIS)

    Van Buskirk, R.D.; Marcus, P.S.

    1994-01-01

    We present an exponentially accurate boundary integral method for calculation the equilibria and dynamics of piece-wise constant distributions of potential vorticity. The method represents contours of potential vorticity as a spectral sum and solves the Biot-Savart equation for the velocity by spectrally evaluating a desingularized contour integral. We use the technique in both an initial-value code and a newton continuation method. Our methods are tested by comparing the numerical solutions with known analytic results, and it is shown that for the same amount of computational work our spectral methods are more accurate than other contour dynamics methods currently in use

  7. Spectral radius of graphs

    CERN Document Server

    Stevanovic, Dragan

    2015-01-01

    Spectral Radius of Graphs provides a thorough overview of important results on the spectral radius of adjacency matrix of graphs that have appeared in the literature in the preceding ten years, most of them with proofs, and including some previously unpublished results of the author. The primer begins with a brief classical review, in order to provide the reader with a foundation for the subsequent chapters. Topics covered include spectral decomposition, the Perron-Frobenius theorem, the Rayleigh quotient, the Weyl inequalities, and the Interlacing theorem. From this introduction, the

  8. Spectral unmixing: estimating partial abundances

    CSIR Research Space (South Africa)

    Debba, Pravesh

    2009-01-01

    Full Text Available techniques is complicated when considering very similar spectral signatures. Iron-bearing oxide/hydroxide/sulfate minerals have similar spectral signatures. The study focuses on how could estimates of abundances of spectrally similar iron-bearing oxide...

  9. Improved characterization of scenes with a combination of MMW radar and radiometer information

    Science.gov (United States)

    Dill, Stephan; Peichl, Markus; Schreiber, Eric; Anglberger, Harald

    2017-05-01

    For security related applications MMW radar and radiometer systems in remote sensing or stand-off configurations are well established techniques. The range of development stages extends from experimental to commercial systems on the civil and military market. Typical examples are systems for personnel screening at airports for concealed object detection under clothing, enhanced vision or landing aid for helicopter and vehicle based systems for suspicious object or IED detection along roads. Due to the physical principle of active (radar) and passive (radiometer) MMW measurement techniques the appearance of single objects and thus the complete scenario is rather different for radar and radiometer images. A reasonable combination of both measurement techniques could lead to enhanced object information. However, some technical requirements should be taken into account. The imaging geometry for both sensors should be nearly identical, the geometrical resolution and the wavelength should be similar and at best the imaging process should be carried out simultaneously. Therefore theoretical and experimental investigations on a suitable combination of MMW radar and radiometer information have been conducted. First experiments in 2016 have been done with an imaging linescanner based on a cylindrical imaging geometry [1]. It combines a horizontal line scan in azimuth with a linear motion in vertical direction for the second image dimension. The main drawback of the system is the limited number of pixel in vertical dimension at a certain distance. Nevertheless the near range imaging results where promising. Therefore the combination of radar and radiometer sensor was assembled on the DLR wide-field-of-view linescanner ABOSCA which is based on a spherical imaging geometry [2]. A comparison of both imaging systems is discussed. The investigations concentrate on rather basic scenarios with canonical targets like flat plates, spheres, corner reflectors and cylinders. First

  10. First TSI observations of the new Compact Lightweight Absolute Radiometer (CLARA)

    Science.gov (United States)

    Walter, B.; Finsterle, W.; Koller, S.; Levesque, P. L.; Pfiffner, D.; Schmutz, W. K.

    2017-12-01

    Continuous and precise Total Solar Irradiance (TSI) measurements are indispensable to evaluate the influence of short- and long-term solar radiative emission variations on the Earth's energy budget. The existence of a potentially long-term trend in the suns activity and whether or not such a trend could be climate effective is still a matter of debate. The Compact Lightweight Absolute Radiometer (CLARA) is one of PMOD/WRC's future contributions to the almost seamless series of space borne TSI measurements since 1978. CLARA is one of three payloads of the Norwegian micro satellite NORSAT-1, along with Langmuir probes for space plasma research and an Automatic Identification System (AIS) receiver to monitor maritime traffic in Norwegian waters. NORSAT-1 was launched July 14th 2017 and the nominal operation of CLARA will start after the instrument commissioning beginning August 21st2017. We present the design, calibration and first TSI observations of CLARA, a new generation of active cavity Electrical Substitution Radiometers (ESR) comprising the latest radiometer developments of PMOD/WRC: i) A three-cavity design for degradation tracking and redundancy, ii) a digital control loop with feed forward system allowing for measurement cadences of 30s, iii) an aperture arrangement to reduce internal scattered light and iv) a new cavity and heatsink design to minimize non-equivalence, size and weight of the instrument. CLARA was end-to-end calibrated against the SI traceable cryogenic radiometer of the TSI Radiometer Facility (TRF) in Boulder (Colorado). The absolute measurement uncertainties for the three SI-traceable TSI detectors of CLARA are 567, 576 and 912 ppm (k = 1).

  11. Preliminary Evaluation of the SMAP Radiometer Soil Moisture Product over China Using In Situ Data

    Directory of Open Access Journals (Sweden)

    Yayong Sun

    2017-03-01

    Full Text Available The Soil Moisture Active Passive (SMAP satellite makes coincident global measurements of soil moisture using an L-band radar instrument and an L-band radiometer. It is crucial to evaluate the errors in the newest L-band SMAP satellite-derived soil moisture products, before they are routinely used in scientific research and applications. This study represents the first evaluation of the SMAP radiometer soil moisture product over China. In this paper, a preliminary evaluation was performed using sparse in situ measurements from 655 China Meteorological Administration (CMA monitoring stations between 1 April 2015 and 31 August 2016. The SMAP radiometer-derived soil moisture product was evaluated against two schemes of original soil moisture and the soil moisture anomaly in different geographical zones and land cover types. Four performance metrics, i.e., bias, root mean square error (RMSE, unbiased root mean square error (ubRMSE, and the correlation coefficient (R, were used in the accuracy evaluation. The results indicated that the SMAP radiometer-derived soil moisture product agreed relatively well with the in situ measurements, with ubRMSE values of 0.058 cm3·cm−3 and 0.039 cm3·cm−3 based on original data and anomaly data, respectively. The values of the SMAP radiometer-based soil moisture product were overestimated in wet areas, especially in the Southwest China, South China, Southeast China, East China, and Central China zones. The accuracies over croplands and in Northeast China were the worst. Soil moisture, surface roughness, and vegetation are crucial factors contributing to the error in the soil moisture product. Moreover, radio frequency interference contributes to the overestimation over the northern portion of the East China zone. This study provides guidelines for the application of the SMAP-derived soil moisture product in China and acts as a reference for improving the retrieval algorithm.

  12. Rectangular spectral collocation

    KAUST Repository

    Driscoll, Tobin A.; Hale, Nicholas

    2015-01-01

    Boundary conditions in spectral collocation methods are typically imposed by removing some rows of the discretized differential operator and replacing them with others that enforce the required conditions at the boundary. A new approach based upon

  13. Vowel Inherent Spectral Change

    CERN Document Server

    Assmann, Peter

    2013-01-01

    It has been traditional in phonetic research to characterize monophthongs using a set of static formant frequencies, i.e., formant frequencies taken from a single time-point in the vowel or averaged over the time-course of the vowel. However, over the last twenty years a growing body of research has demonstrated that, at least for a number of dialects of North American English, vowels which are traditionally described as monophthongs often have substantial spectral change. Vowel Inherent Spectral Change has been observed in speakers’ productions, and has also been found to have a substantial effect on listeners’ perception. In terms of acoustics, the traditional categorical distinction between monophthongs and diphthongs can be replaced by a gradient description of dynamic spectral patterns. This book includes chapters addressing various aspects of vowel inherent spectral change (VISC), including theoretical and experimental studies of the perceptually relevant aspects of VISC, the relationship between ar...

  14. LNG pool fire spectral data and calculation of emissive power

    International Nuclear Information System (INIS)

    Raj, Phani K.

    2007-01-01

    Spectral description of thermal emission from fires provides a fundamental basis on which the fire thermal radiation hazard assessment models can be developed. Several field experiments were conducted during the 1970s and 1980s to measure the thermal radiation field surrounding LNG fires. Most of these tests involved the measurement of fire thermal radiation to objects outside the fire envelope using either narrow-angle or wide-angle radiometers. Extrapolating the wide-angle radiometer data without understanding the nature of fire emission is prone to errors. Spectral emissions from LNG fires have been recorded in four test series conducted with LNG fires on different substrates and of different diameters. These include the AGA test series of LNG fires on land of diameters 1.8 and 6 m, 35 m diameter fire on an insulated concrete dike in the Montoir tests conducted by Gaz de France, a 1976 test with 13 m diameter and the 1980 tests with 10 m diameter LNG fire on water carried out at China Lake, CA. The spectral data from the Montoir test series have not been published in technical journals; only recently has some data from this series have become available. This paper presents the details of the LNG fire spectral data from, primarily, the China Lake test series, their analysis and results. Available data from other test series are also discussed. China Lake data indicate that the thermal radiation emission from 13 m diameter LNG fire is made up of band emissions of about 50% of energy by water vapor (band emission), about 25% by carbon dioxide and the remainder constituting the continuum emission by luminous soot. The emissions from the H 2 O and CO 2 bands are completely absorbed by the intervening atmosphere in less than about 200 m from the fire, even in the relatively dry desert air. The effective soot radiation constitutes only about 23% during the burning period of methane and increases slightly when other higher hydrocarbon species (ethane, propane, etc.) are

  15. Spectrally selective glazings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-08-01

    Spectrally selective glazing is window glass that permits some portions of the solar spectrum to enter a building while blocking others. This high-performance glazing admits as much daylight as possible while preventing transmission of as much solar heat as possible. By controlling solar heat gains in summer, preventing loss of interior heat in winter, and allowing occupants to reduce electric lighting use by making maximum use of daylight, spectrally selective glazing significantly reduces building energy consumption and peak demand. Because new spectrally selective glazings can have a virtually clear appearance, they admit more daylight and permit much brighter, more open views to the outside while still providing the solar control of the dark, reflective energy-efficient glass of the past. This Federal Technology Alert provides detailed information and procedures for Federal energy managers to consider spectrally selective glazings. The principle of spectrally selective glazings is explained. Benefits related to energy efficiency and other architectural criteria are delineated. Guidelines are provided for appropriate application of spectrally selective glazing, and step-by-step instructions are given for estimating energy savings. Case studies are also presented to illustrate actual costs and energy savings. Current manufacturers, technology users, and references for further reading are included for users who have questions not fully addressed here.

  16. Precipitation Estimation Using Combined Radar/Radiometer Measurements Within the GPM Framework

    Science.gov (United States)

    Hou, Arthur

    2012-01-01

    The Global Precipitation Measurement (GPM) Mission is an international satellite mission specifically designed to unify and advance precipitation measurements from a constellation of research and operational microwave sensors. The GPM mission centers upon the deployment of a Core Observatory in a 65o non-Sun-synchronous orbit to serve as a physics observatory and a transfer standard for intersatellite calibration of constellation radiometers. The GPM Core Observatory will carry a Ku/Ka-band Dual-frequency Precipitation Radar (DPR) and a conical-scanning multi-channel (10-183 GHz) GPM Microwave Radiometer (GMI). The DPR will be the first dual-frequency radar in space to provide not only measurements of 3-D precipitation structures but also quantitative information on microphysical properties of precipitating particles needed for improving precipitation retrievals from microwave sensors. The DPR and GMI measurements will together provide a database that relates vertical hydrometeor profiles to multi-frequency microwave radiances over a variety of environmental conditions across the globe. This combined database will be used as a common transfer standard for improving the accuracy and consistency of precipitation retrievals from all constellation radiometers. For global coverage, GPM relies on existing satellite programs and new mission opportunities from a consortium of partners through bilateral agreements with either NASA or JAXA. Each constellation member may have its unique scientific or operational objectives but contributes microwave observations to GPM for the generation and dissemination of unified global precipitation data products. In addition to the DPR and GMI on the Core Observatory, the baseline GPM constellation consists of the following sensors: (1) Special Sensor Microwave Imager/Sounder (SSMIS) instruments on the U.S. Defense Meteorological Satellite Program (DMSP) satellites, (2) the Advanced Microwave Scanning Radiometer-2 (AMSR-2) on the GCOM-W1

  17. Airborne spectral measurements of surface anisotropy during SCAR-B

    Science.gov (United States)

    Tsay, Si-Chee; King, Michael D.; Arnold, G. Thomas; Li, Jason Y.

    1998-12-01

    During the Smoke, Clouds, and Radiation-Brazil (SCAR-B) deployment, angular distributions of spectral reflectance for vegetated surfaces and smoke layers were measured using the scanning cloud absorption radiometer (CAR) mounted on the University of Washington C-131A research aircraft. The CAR contains 13 narrowband spectral channels between 0.3 and 2.3 μm with a 190° scan aperture (5° before zenith to 5° past nadir) and 1° instantaneous field of view. The bidirectional reflectance is obtained by flying a clockwise circular orbit above the surface, resulting in a ground track ˜3 km in diameter within about 2 min. Although the CAR measurements are contaminated by minor atmospheric effects, results show distinct spectral characteristics for various types of surfaces. Spectral bidirectional reflectances of three simple and well-defined surfaces are presented: cerrado (August 18, 1995) and dense forest (August 25, 1995), both measured in Brazil under nearly clear-sky conditions, and thick smoke layers over dense forest (September 6 and 11, 1995). The bidirectional reflectances of cerrado and dense forest revealed fairly symmetric patterns along the principal plane, with varying maximal strengths and widths spectrally in the backscattering direction. In the shortwave-infrared region the aerosol effect is very small due to low spectral optical depth. Also, these backscattering maxima can be seen on the bidirectional reflectance of smoke layer over dense forest. These detailed measurements of the angular distribution of spectral reflectance can be parameterized by a few independent variables and utilized to retrieve either surface characteristics or aerosol microphysical and optical properties (e.g., size distribution and single-scattering parameters), if proper physical and radiation models are used. The spectral-hemispherical albedo of these surfaces is obtained directly by integrating all angular measurements and is compared with the measured nadir reflectance

  18. Remote Sensing of Surface Soil Moisture using Semi-Concurrent Radar and Radiometer Observations

    Science.gov (United States)

    Li, L.; Ouellette, J. D.; Colliander, A.; Cosh, M. H.; Caldwell, T. G.; Walker, J. P.

    2017-12-01

    Radar backscatter and radiometer brightness temperature both have well-documented sensitivity to surface soil moisture, particularly in the microwave regime. While radiometer-derived soil moisture retrievals have been shown to be stable and accurate, they are only available at coarse spatial resolutions on the order of tens of kilometers. Backscatter from Synthetic Aperture Radar (SAR) is similarly sensitive to soil moisture but can yield higher spatial resolutions, with pixel sizes about an order of magnitude smaller. Soil moisture retrieval from radar backscatter is more difficult, however, due to the combined sensitivity of radar scattering to surface roughness, vegetation structure, and soil moisture. The algorithm uses a time-series of SAR data to retrieval soil moisture information, constraining the SAR-derived soil moisture estimates with radiometer observations. This effectively combines the high spatial resolution offered by SAR with the precision offered by passive radiometry. The algorithm is a change detection approach which maps changes in the radar backscatter to changes in surface soil moisture. This new algorithm differs from existing retrieval techniques in that it does not require ancillary vegetation information, but assumes vegetation and surface roughness are stable between pairs of consecutive radar overpasses. Furthermore, this method does not require a radar scattering model for the vegetation canopy, nor the use of a training data set. The algorithm works over a long time series, and is constrained by hard bounds which are defined using a coarse-resolution radiometer soil moisture product. The presentation will include soil moisture retrievals from Soil Moisture Active/Passive (SMAP) SAR data. Two sets of optimization bounds will constrain the radar change detection algorithm: one defined by SMAP radiometer retrievals and one defined by WindSat radiometer retrievals. Retrieved soil moisture values will be presented on a world map and will

  19. Development of a Compact High Altitude Imager and Sounding Radiometer (CHAISR)

    Science.gov (United States)

    Choi, R. K. Y.; Min, S.; Cho, Y. J.; Kim, K. H.; Ha, J. C.; Joo, S. W.

    2017-12-01

    Joint Civilian-Military Committee, under Advisory Council on Science and Technology, Korea, has approved a technology demonstration project for developing a lightweight HALE UAV (High-Altitude, Long Endurance). It aims to operate at lower stratosphere, i.e. altitude of 16 20 km, offering unique observational platform to atmospheric research community as pseudo-satellite. NIMS (National Institute of Meteorological Sciences, Korea) is responsible for a payload for atmospheric science, a Compact High Altitude Imager and Sounding Radiometer (CHAISR) to demonstrate scientific observations at lower stratosphere in the interest of improving numerical weather prediction model. CHAISR consists of three microwave radiometers (MWR) with 16 channel, and medium resolution cameras operating in a visible and infrared spectrum. One of the technological challenges for CHAISR is to accommodate those instruments within 50 W of power consumption. CHAISR will experience temperature up to -75°C, while pressure as low as 50 hPa at operational altitude. It requires passive thermal control of the payload to keep electronic subsystems warm enough for instrument operation with minimal power available. Safety features, such as payload power management and thermal control, are considered with minimal user input. Three radiometers measure atmospheric brightness temperature at frequency at around 20, 40, and 50 GHz. Retrieval process yields temperature and humidity profiles with cross track scan along the flight line. Estimated total weight of all radiometer hardware, from the antennas to data acquisition system, is less than 0.8 kg and a maximum power consumption is 15.2 W. With not enough power for blackbody calibration target, radiometers use zenith sky view at lower stratosphere as an excellent calibration target for a conventional tipping-curve calibration. Spatial distributions of clouds from visible and surface temperature from thermal cameras are used as additional information for

  20. A Radar/Radiometer Instrument for Mapping Soil Moisture and Ocean Salinity

    Science.gov (United States)

    Hildebrand, Peter H.; Hilliard, Laurence; Rincon, Rafael; LeVine, David; Mead, James

    2003-01-01

    The RadSTAR instrument combines an L-band, digital beam-forming radar with an L-band synthetic aperture, thinned array (STAR) radiometer. The RadSTAR development will support NASA Earth science goals by developing a novel, L-band scatterometer/ radiometer that measures Earth surface bulk material properties (surface emissions and backscatter) as well as surface characteristics (backscatter). Present, real aperture airborne L-Band active/passive measurement systems such as the JPUPALS (Wilson, et al, 2000) provide excellent sampling characteristics, but have no scanning capabilities, and are extremely large; the huge JPUPALS horn requires a the C-130 airborne platform, operated with the aft loading door open during flight operation. The approach used for the upcoming Aquarius ocean salinity mission or the proposed Hydros soil mission use real apertures with multiple fixed beams or scanning beams. For real aperture instruments, there is no upgrade path to scanning over a broad swath, except rotation of the whole aperture, which is an approach with obvious difficulties as aperture size increases. RadSTAR will provide polarimetric scatterometer and radiometer measurements over a wide swath, in a highly space-efficient configuration. The electronic scanning approaches provided through STAR technology and digital beam forming will enable the large L-band aperture to scan efficiently over a very wide swath. RadSTAR technology development, which merges an interferometric radiometer with a digital beam forming scatterometer, is an important step in the path to space for an L-band scatterometer/radiometer. RadSTAR couples a patch array antenna with a 1.26 GHz digital beam forming radar scatterometer and a 1.4 GHz STAR radiometer to provide Earth surface backscatter and emission measurements in a compact, cross-track scanning instrument with no moving parts. This technology will provide the first L-band, emission and backscatter measurements in a compact aircraft instrument

  1. Development of an Internally-Calibrated Wide-Band Airborne Microwave Radiometer to Provide High-Resolution Wet-Tropospheric Path Delay Measurements for SWOT (HAMMR - High-frequency Airborne Microwave and Millimeter-wave Radiometer)

    Data.gov (United States)

    National Aeronautics and Space Administration — Development of an Internally-Calibrated Wide-Band Airborne Microwave Radiometer to Provide High-Resolution Wet-Tropospheric Path Delay Measurements for SWOT (HAMMR -...

  2. CRISS power spectral density

    International Nuclear Information System (INIS)

    Vaeth, W.

    1979-04-01

    The correlation of signal components at different frequencies like higher harmonics cannot be detected by a normal power spectral density measurement, since this technique correlates only components at the same frequency. This paper describes a special method for measuring the correlation of two signal components at different frequencies: the CRISS power spectral density. From this new function in frequency analysis, the correlation of two components can be determined quantitatively either they stem from one signal or from two diverse signals. The principle of the method, suitable for the higher harmonics of a signal as well as for any other frequency combinations is shown for the digital frequency analysis technique. Two examples of CRISS power spectral densities demonstrates the operation of the new method. (orig.) [de

  3. Parametric Explosion Spectral Model

    Energy Technology Data Exchange (ETDEWEB)

    Ford, S R; Walter, W R

    2012-01-19

    Small underground nuclear explosions need to be confidently detected, identified, and characterized in regions of the world where they have never before occurred. We develop a parametric model of the nuclear explosion seismic source spectrum derived from regional phases that is compatible with earthquake-based geometrical spreading and attenuation. Earthquake spectra are fit with a generalized version of the Brune spectrum, which is a three-parameter model that describes the long-period level, corner-frequency, and spectral slope at high-frequencies. Explosion spectra can be fit with similar spectral models whose parameters are then correlated with near-source geology and containment conditions. We observe a correlation of high gas-porosity (low-strength) with increased spectral slope. The relationship between the parametric equations and the geologic and containment conditions will assist in our physical understanding of the nuclear explosion source.

  4. Photovoltaic spectral responsivity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Emery, K.; Dunlavy, D.; Field, H.; Moriarty, T. [National Renewable Energy Lab., Golden, CO (United States)

    1998-09-01

    This paper discusses the various elemental random and nonrandom error sources in typical spectral responsivity measurement systems. The authors focus specifically on the filter and grating monochrometer-based spectral responsivity measurement systems used by the Photovoltaic (PV) performance characterization team at NREL. A variety of subtle measurement errors can occur that arise from a finite photo-current response time, bandwidth of the monochromatic light, waveform of the monochromatic light, and spatial uniformity of the monochromatic and bias lights; the errors depend on the light source, PV technology, and measurement system. The quantum efficiency can be a function of he voltage bias, light bias level, and, for some structures, the spectral content of the bias light or location on the PV device. This paper compares the advantages and problems associated with semiconductor-detector-based calibrations and pyroelectric-detector-based calibrations. Different current-to-voltage conversion and ac photo-current detection strategies employed at NREL are compared and contrasted.

  5. Spectral analysis by correlation

    International Nuclear Information System (INIS)

    Fauque, J.M.; Berthier, D.; Max, J.; Bonnet, G.

    1969-01-01

    The spectral density of a signal, which represents its power distribution along the frequency axis, is a function which is of great importance, finding many uses in all fields concerned with the processing of the signal (process identification, vibrational analysis, etc...). Amongst all the possible methods for calculating this function, the correlation method (correlation function calculation + Fourier transformation) is the most promising, mainly because of its simplicity and of the results it yields. The study carried out here will lead to the construction of an apparatus which, coupled with a correlator, will constitute a set of equipment for spectral analysis in real time covering the frequency range 0 to 5 MHz. (author) [fr

  6. Spectral backward radiation profile

    International Nuclear Information System (INIS)

    Kwon, Sung Duck; Lee, Keun Hyun; Kim, Bo Ra; Yoon, Suk Soo

    2004-01-01

    Ultrasonic backward radiation profile is frequency-dependent when incident region has deptional gradient of acoustical properties or multi-layers. Until now, we have measured the profiles of principal frequencies of used transducers so that it was not easy to understand the change of the frequency component and spectrum of backward radiation from the profile. We tried to measure the spectral backward radiation profiles using DFP(digital filer package) Lecroy DSO. The very big changes in the shape and pattern of spectral backward radiation profiles leads to the conclusion that this new try could be very effective tool to evaluate frequency dependent surface area.

  7. Design and first plasma measurements of the ITER-ECE prototype radiometer

    Energy Technology Data Exchange (ETDEWEB)

    Austin, M. E.; Brookman, M. W.; Rowan, W. L. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States); Danani, S. [ITER-India/Institute for Plasma Research, Bhat, Gandhinagar 382428 (India); Bryerton, E. W.; Dougherty, P. [Virginia Diodes, Inc., Charlottesville, Virginia 22902 (United States)

    2016-11-15

    On ITER, second harmonic optically thick electron cyclotron emission (ECE) in the range of 220-340 GHz will supply the electron temperature (T{sub e}). To investigate the requirements and capabilities prescribed for the ITER system, a prototype radiometer covering this frequency range has been developed by Virginia Diodes, Inc. The first plasma measurements with this instrument have been carried out on the DIII-D tokamak, with lab bench tests and measurements of third through fifth harmonic ECE from high T{sub e} plasmas. At DIII-D the instrument shares the transmission line of the Michelson interferometer and can simultaneously acquire data. Comparison of the ECE radiation temperature from the absolutely calibrated Michelson and the prototype receiver shows that the ITER radiometer provides accurate measurements of the millimeter radiation across the instrument band.

  8. The along track scanning radiometer - an analysis of coincident ship and satellite measurements

    Science.gov (United States)

    Barton, I. J.; Prata, A. J.; Llewellyn-Jones, D. T.

    1993-05-01

    Following the successful launch of the ERS-1 satellite in July 1991 we have undertaken several geophysical validation cruises in the Coral Sea. The prime aim of these cruises was to compare the sea surface temperature (SST) derived from the Along Track Scanning Radiometer (ATSR) with that measured using precision radiometers mounted on the ships. On most occasions when simultaneous satellite and ship measurements were taken we also launched a radiosonde from one of the research vessels. The results suggest that the ATSR is able to measure the ``skin'' temperature of the sea surface with an accuracy suitable for climate research applications. A case study comparison between the AVHRR and ATSR SST products will also be presented.

  9. Nimbus-2 High-Resolution Infrared Radiometer (HRIR) Imagery of Cloud Cover at Night on 70 mm Film V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The HRIRN2IM data product contains scanned negatives of photofacsimile 70mm film strips from the Nimbus-2 High-Resolution Infrared Radiometer. The images contain...

  10. Wide-band Millimeter and Sub-Millimeter Wave Radiometer Instrument to Measure Tropospheric Water and Cloud ICE

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop, fabricate and test a new, multi-frequency millimeter and sub-millimeter-wave radiometer instrument to provide critically-needed measurements...

  11. NPP Visible Infrared Imager-Radiometer Suite (VIIRS) Diffuse Attenuation Coefficient for Downwelling Irradiance (KD) Global Mapped Data

    Data.gov (United States)

    National Aeronautics and Space Administration — The Visible and Infrared Imager/Radiometer Suite (VIIRS) is a multi-disciplinary instrument that is being flown on the Joint Polar Satellite System (JPSS) series of...

  12. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Near Constant Contrast (NCC) Imagery Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument onboard the...

  13. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Cloud Base Height (CBH) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of Cloud Base Heights (CBH) from the Visible Infrared Imaging Radiometer Suite...

  14. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Cloud Type and Phase Environmental Data Record (EDR) from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of cloud type and phase from the Visible Infrared Imaging Radiometer Suite (VIIRS)...

  15. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Land Surface Temperature (LST) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of Land Surface Temperature (LST) from the Visible Infrared Imaging Radiometer Suite...

  16. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Cloud Cover Layer (CCL) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality Environmental Data Record (EDR) of Cloud Cover Layers (CCL) from the Visible Infrared Imaging Radiometer Suite (VIIRS)...

  17. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Cloud Optical Thickness (COT) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of Cloud Optical Thickness (COT) from the Visible Infrared Imaging Radiometer Suite...

  18. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Ice Thickness and Age Environmental Data Records (EDRs) from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of Ice Thickness and Age from the Visible Infrared Imaging Radiometer Suite (VIIRS)...

  19. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Ice Surface Temperature (IST) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument onboard the...

  20. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Cloud Top Height (CTH) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument onboard the...

  1. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Cloud Top Temperature (CTT) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument onboard the...

  2. A precise narrow-beam filter infrared radiometer and its use with lidar in the ARM Program

    International Nuclear Information System (INIS)

    Platt, C.M.R.

    1992-05-01

    The first six months of the grant (December 1991--May 1992) have been taken up with the design and specification for the new narrow-beam radiometer. The radiometer will be built and tested at the Division of Atmospheric Research over the next three months. Improved algorithms for obtaining cloud extinction have also been developed. It is proposed during 1993 to use the radiometer in conjunction with a new CSIRO 3-wavelength lidar in the ARM PROBE experiment at Kavieng, New Guinea, which is a test mission under tropical conditions for the ARM CART Tropical West Pacific site, and is part of the TOGA COARE experiment. During the latter part of 1992, the radiometer will be tested thoroughly and tested at the Division of Atmospheric Research, Aspendale

  3. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Cloud Effective Particle Size (CEPS) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of Cloud Effective Particle Size (CEPS) from the Visible Infrared Imaging Radiometer...

  4. JPSS NOAA Visible Infrared Imaging Radiometer Suite (VIIRS) Cloud Top Pressure (CTP) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument onboard the...

  5. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Sea Ice Characterization (SIC) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains an Environmental Data Record (EDR) of Sea Ice Characterization (SIC) from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument...

  6. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Cloud Height (Top and Base) Environmental Data Record (EDR) from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of cloud height (top and base) from the Visible Infrared Imaging Radiometer Suite...

  7. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Ocean Color/Chlorophyll (OCC) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of Ocean Color/Chlorophyll (OCC) from the Visible Infrared Imaging Radiometer Suite...

  8. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Volcanic Ash Detection and Height Environmental Data Record (EDR) from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of volcanic ash from the Visible Infrared Imaging Radiometer (VIIRS) instrument...

  9. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Imagery (not Near Constant Contrast) Environmental Data Record (EDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument onboard the...

  10. HURRICANE AND SEVERE STORM SENTINEL (HS3) GLOBAL HAWK HIGH ALTITUDE MMIC SOUNDING RADIOMETER (HAMSR) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Hurricane and Severe Storm Sentinel (HS3) Global Hawk High Altitude MMIC Sounding Radiometer (HAMSR) datasets include measurements gathered by the HAMSR...

  11. Assimilation of global radar backscatter and radiometer brightness temperature observations to improve soil moisture and land evaporation estimates

    NARCIS (Netherlands)

    Lievens, H.; Martens, B.; Verhoest, N.E.C.; Hahn, S.; Reichle, R.H.; Gonzalez Miralles, D.

    2016-01-01

    Active radar backscatter (σ°) observations from the Advanced Scatterometer (ASCAT) and passive radiometer brightness temperature (TB) observations from the Soil Moisture Ocean Salinity (SMOS) mission are assimilated either individually or jointly into the Global Land Evaporation Amsterdam Model

  12. Weight estimates and packaging techniques for the microwave radiometer spacecraft. [shuttle compatible design

    Science.gov (United States)

    Jensen, J. K.; Wright, R. L.

    1981-01-01

    Estimates of total spacecraft weight and packaging options were made for three conceptual designs of a microwave radiometer spacecraft. Erectable structures were found to be slightly lighter than deployable structures but could be packaged in one-tenth the volume. The tension rim concept, an unconventional design approach, was found to be the lightest and transportable to orbit in the least number of shuttle flights.

  13. Global Land Surface Temperature From the Along-Track Scanning Radiometers

    Science.gov (United States)

    Ghent, D. J.; Corlett, G. K.; Göttsche, F.-M.; Remedios, J. J.

    2017-11-01

    The Leicester Along-Track Scanning Radiometer (ATSR) and Sea and Land Surface Temperature Radiometer (SLSTR) Processor for LAnd Surface Temperature (LASPLAST) provides global land surface temperature (LST) products from thermal infrared radiance data. In this paper, the state-of-the-art version of LASPLAST, as deployed in the GlobTemperature project, is described and applied to data from the Advanced Along-Track Scanning Radiometer (AATSR). The LASPLAST retrieval formulation for LST is a nadir-only, two-channel, split-window algorithm, based on biome classification, fractional vegetation, and across-track water vapor dependences. It incorporates globally robust retrieval coefficients derived using highly sampled atmosphere profiles. LASPLAST benefits from appropriate spatial resolution auxiliary information and a new probabilistic-based cloud flagging algorithm. For the first time for a satellite-derived LST product, pixel-level uncertainties characterized in terms of random, locally correlated, and systematic components are provided. The new GlobTemperature GT_ATS_2P Version 1.0 product has been validated for 1 year of AATSR data (2009) against in situ measurements acquired from "gold standard reference" stations: Gobabeb, Namibia, and Evora, Portugal; seven Surface Radiation Budget stations, and the Atmospheric Radiation Measurement station at Southern Great Plains. These data show average absolute biases for the GT_ATS_2P Version 1.0 product of 1.00 K in the daytime and 1.08 K in the nighttime. The improvements in data provenance including better accuracy, fully traceable retrieval coefficients, quantified uncertainty, and more detailed information in the new harmonized format of the GT_ATS_2P product will allow for more significant exploitation of the historical LST data record from the ATSRs and a valuable near-real-time service from the Sea and Land Surface Temperature Radiometers (SLSTRs).

  14. Microfluidic labeling of biomolecules with radiometals for use in nuclear medicine.

    Science.gov (United States)

    Wheeler, Tobias D; Zeng, Dexing; Desai, Amit V; Önal, Birce; Reichert, David E; Kenis, Paul J A

    2010-12-21

    Radiometal-based radiopharmaceuticals, used as imaging and therapeutic agents in nuclear medicine, consist of a radiometal that is bound to a targeting biomolecule (BM) using a bifunctional chelator (BFC). Conventional, macroscale radiolabeling methods use an excess of the BFC-BM conjugate (ligand) to achieve high radiolabeling yields. Subsequently, to achieve maximal specific activity (minimal amount of unlabeled ligand), extensive chromatographic purification is required to remove unlabeled ligand, often resulting in longer synthesis times and loss of imaging sensitivity due to radioactive decay. Here we describe a microreactor that overcomes the above issues through integration of efficient mixing and heating strategies while working with small volumes of concentrated reagents. As a model reaction, we radiolabel 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) conjugated to the peptide cyclo(Arg-Gly-Asp-DPhe-Lys) with (64)Cu(2+). We show that the microreactor (made from polydimethylsiloxane and glass) can withstand 260 mCi of activity over 720 hours and retains only minimal amounts of (64)Cu(2+) (50 µM), yields of over 90% can be achieved in the microreactor when using a 1:1 stoichiometry of radiometal to BFC-BM. These high yields eliminate the need for use of excess amounts of often precious BM and obviate the need for a chromatographic purification process to remove unlabeled ligand. The results reported here demonstrate the potential of microreactor technology to improve the production of patient-tailored doses of radiometal-based radiopharmaceuticals in the clinic.

  15. A General Analysis of the Impact of Digitization in Microwave Correlation Radiometers

    Directory of Open Access Journals (Sweden)

    Hyuk Park

    2011-06-01

    Full Text Available This study provides a general framework to analyze the effects on correlation radiometers of a generic quantization scheme and sampling process. It reviews, unifies and expands several previous works that focused on these effects separately. In addition, it provides a general theoretical background that allows analyzing any digitization scheme including any number of quantization levels, irregular quantization steps, gain compression, clipping, jitter and skew effects of the sampling period.

  16. Atmospheric water distribution in cyclones as seen with Scanning Multichannel Microwave Radiometers (SMMR)

    Science.gov (United States)

    Katsaros, K. B.; Mcmurdie, L. A.

    1983-01-01

    Passive microwave measurements are used to study the distribution of atmospheric water in midlatitude cyclones. The integrated water vapor, integrated liquid water, and rainfall rate are deduced from the brightness temperatures at microwave frequencies measured by the Scanning Multichannel Microwave Radiometer (SMRR) flown on both the Seasat and Nimbus 7 satellites. The practical application of locating fronts by the cyclone moisture pattern over oceans is shown, and the relationship between the quantity of coastal rainfall and atmospheric water content is explored.

  17. Absolute intensity calibration of the 32-channel heterodyne radiometer on experimental advanced superconducting tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X.; Zhao, H. L.; Liu, Y., E-mail: liuyong@ipp.ac.cn; Li, E. Z.; Han, X.; Ti, A.; Hu, L. Q.; Zhang, X. D. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Domier, C. W.; Luhmann, N. C. [Department of Electrical and Computer Engineering, University of California at Davis, Davis, California 95616 (United States)

    2014-09-15

    This paper presents the results of the in situ absolute intensity calibration for the 32-channel heterodyne radiometer on the experimental advanced superconducting tokamak. The hot/cold load method is adopted, and the coherent averaging technique is employed to improve the signal to noise ratio. Measured spectra and electron temperature profiles are compared with those from an independent calibrated Michelson interferometer, and there is a relatively good agreement between the results from the two different systems.

  18. A radiative transfer model for sea surface temperature retrieval for the along-track scanning radiometer

    Science.gov (United States)

    ZáVody, A. M.; Mutlow, C. T.; Llewellyn-Jones, D. T.

    1995-01-01

    The measurements made by the along-track scanning radiometer are now converted routinely into sea surface temperature (SST). The details of the atmospheric model which had been used for deriving the SST algorithms are given, together with tables of the coefficients in the algorithms for the different SST products. The accuracy of the retrieval under normal conditions and the effect of errors in the model on the retrieved SST are briefly discussed.

  19. CORRECTION OF THE TEMPERATURE EFFECT IN 1020 NM BAND OF SUN-SKY RADIOMETER

    Directory of Open Access Journals (Sweden)

    K. Li

    2018-04-01

    Full Text Available Aerosol is an important part of the earth-atmosphere system. It can directly and indirectly influence solar radiation and then affect the energy balance of earth-atmosphere system. AERONET, as the largest ground-based observation network, provides multi-parameters of aerosol from more than 600 hundred sites using sun-sky radiometer, which contains 9 channels from 340 nm to 1640 nm. Among which, 1020 nm channel is greatly influenced by the temperature. In this paper, a new correction method of 1020 nm band is introduced. The new method transfers the temperature correction coefficient of the master radiometer to the comparative one. The filed calibration experiment shown that the temperature correction coefficient obtained by this method is close to the result from the temperature controlled chamber, and the difference is about 2.1 %. This new method is easy-to-use, and its accuracy is comparable to the standard one. It is more applicable for large-scale instrument calibration. In principle, this method is applicable to all bands of the sun-sky radiometer.

  20. High spatial resolution upgrade of the electron cyclotron emission radiometer for the DIII-D tokamak.

    Science.gov (United States)

    Truong, D D; Austin, M E

    2014-11-01

    The 40-channel DIII-D electron cyclotron emission (ECE) radiometer provides measurements of Te(r,t) at the tokamak midplane from optically thick, second harmonic X-mode emission over a frequency range of 83-130 GHz. The frequency spacing of the radiometer's channels results in a spatial resolution of ∼1-3 cm, depending on local magnetic field and electron temperature. A new high resolution subsystem has been added to the DIII-D ECE radiometer to make sub-centimeter (0.6-0.8 cm) resolution Te measurements. The high resolution subsystem branches off from the regular channels' IF bands and consists of a microwave switch to toggle between IF bands, a switched filter bank for frequency selectivity, an adjustable local oscillator and mixer for further frequency down-conversion, and a set of eight microwave filters in the 2-4 GHz range. Higher spatial resolution is achieved through the use of a narrower (200 MHz) filter bandwidth and closer spacing between the filters' center frequencies (250 MHz). This configuration allows for full coverage of the 83-130 GHz frequency range in 2 GHz bands. Depending on the local magnetic field, this translates into a "zoomed-in" analysis of a ∼2-4 cm radial region. Expected uses of these channels include mapping the spatial dependence of Alfven eigenmodes, geodesic acoustic modes, and externally applied magnetic perturbations. Initial Te measurements, which demonstrate that the desired resolution is achieved, are presented.

  1. A W-Band Radiometer with the Offset Parabolic Antenna for Radiometric Measurements

    Directory of Open Access Journals (Sweden)

    Li Wu

    2016-01-01

    Full Text Available This paper deals with the development of a W-band noise-adding radiometer which combines the millimeter-wave (MMW radiometric measurements with a high-resolution imager. The offset parabolic antenna is presented to achieve an accurate measurement and a high resolution. To reduce the cross-polarization level of the antenna, a multimode feed horn with a multistep structure is proposed to match the focal region fields of the reflector. It has advantages over the corrugated horns in lower mass and easier manufacturing. In addition, due to an unavoidable settling time for the noise-adding radiometer output signal passing through the low-pass filter, a theoretical criterion for the optimum duty cycle determination to reject extraneous contributions from the transient is proposed in this paper. The appropriate duty cycle threshold is 0.33 for the developed W-band radiometer. Also, a geometric correction method is presented to correct the obtained passive image suffering from a distortion for a better image interpretation. Preliminary experimental results are given to illustrate and verify the presented techniques.

  2. PAU-SA: A Synthetic Aperture Interferometric Radiometer Test Bed for Potential Improvements in Future Missions

    Directory of Open Access Journals (Sweden)

    Merce Vall-llosera

    2012-06-01

    Full Text Available The Soil Moisture and Ocean Salinity (SMOS mission is an Earth Explorer Opportunity mission from the European Space Agency (ESA. Its goal is to produce global maps of soil moisture and ocean salinity using the Microwave Imaging Radiometer by Aperture Synthesis (MIRAS. The purpose of the Passive Advanced Unit Synthetic Aperture (PAU-SA instrument is to study and test some potential improvements that could eventually be implemented in future missions using interferometric radiometers such as the Geoestacionary Atmosferic Sounder (GAS, the Precipitation and All-weather Temperature and Humidity (PATH and the Geostationary Interferometric Microwave Sounder (GIMS. Both MIRAS and PAU-SA are Y-shaped arrays with uniformly distributed antennas, but the receiver topology and the processing unit are quite different. The purpose of this work is to identify the elements in the MIRAS’s design susceptible of improvement and apply them in the PAU-SA instrument demonstrator, to test them in view of these future interferometric radiometer missions.

  3. Remote sensing of the lightning heating effect duration with ground-based microwave radiometer

    Science.gov (United States)

    Jiang, Sulin; Pan, Yun; Lei, Lianfa; Ma, Lina; Li, Qing; Wang, Zhenhui

    2018-06-01

    Artificially triggered lightning events from May 26, 2017 to July 16, 2017 in Guangzhou Field Experiment Site for Lightning Research and Test (GFESL) were intentionally remotely sensed with a ground-based microwave radiometer for the first time in order to obtain the features of lightning heating effect. The microwave radiometer antenna was adjusted to point at a certain elevation angle towards the expected artificially triggered lightning discharging path. Eight of the 16 successfully artificially triggered lightning events were captured and the brightness temperature data at four frequencies in K and V bands were obtained. The results from data time series analysis show that artificially triggered lightning can make the radiometer generate brightness temperature pulses, and the amplitudes of these pulses are in the range of 2.0 K to 73.8 K. The brightness temperature pulses associated with 7 events can be used to estimate the duration of lightning heating effect through accounting the number of the pulses in the continuous pulse sequence and the sampling interval between four frequencies. The maximum duration of the lightning heating effect is 1.13 s, the minimum is 0.172 s, and the average is 0.63 s.

  4. Correction of the Temperature Effect in 1020 NM Band of Sun-Sky Radiometer

    Science.gov (United States)

    Li, K.; Li, Z.; Li, D.; Xie, Y.; Xu, H.

    2018-04-01

    Aerosol is an important part of the earth-atmosphere system. It can directly and indirectly influence solar radiation and then affect the energy balance of earth-atmosphere system. AERONET, as the largest ground-based observation network, provides multi-parameters of aerosol from more than 600 hundred sites using sun-sky radiometer, which contains 9 channels from 340 nm to 1640 nm. Among which, 1020 nm channel is greatly influenced by the temperature. In this paper, a new correction method of 1020 nm band is introduced. The new method transfers the temperature correction coefficient of the master radiometer to the comparative one. The filed calibration experiment shown that the temperature correction coefficient obtained by this method is close to the result from the temperature controlled chamber, and the difference is about 2.1 %. This new method is easy-to-use, and its accuracy is comparable to the standard one. It is more applicable for large-scale instrument calibration. In principle, this method is applicable to all bands of the sun-sky radiometer.

  5. Longterm and spatial variability of Aerosol optical properties measured by sky radiometer in Japan sites

    Science.gov (United States)

    Aoki, K.

    2016-12-01

    Aerosols and cloud play an important role in the climate change. We started the long-term monitoring of aerosol and cloud optical properties since 1990's by using sky radiometer (POM-01, 02; Prede Co. Ltd., Japan). We provide the information, in this presentation, on the aerosol optical properties with respect to their temporal and spatial variability in Japan site (ex. Sapporo, Toyama, Kasuga and etc). The global distributions of aerosols have been derived from earth observation satellite and have been simulated in numerical models, which assume optical parameters. However, these distributions are difficult to derive because of variability in time and space. Therefore, Aerosol optical properties were investigated using the measurements from ground-based and ship-borne sky radiometer. The sky radiometer is an automatic instrument that takes observations only in daytime under the clear sky conditions. Observation of diffuse solar intensity interval was made every ten or five minutes by once. The aerosol optical properties were computed using the SKYRAD.pack version 4.2. The obtained Aerosol optical properties (Aerosol optical thickness, Ångström exponent, Single scattering albedo, and etc.) and size distribution volume clearly showed spatial and temporal variability in Japan area. In this study, we present the temporal and spatial variability of Aerosol optical properties at several Japan sites, applied to validation of satellite and numerical models. This project is validation satellite of GCOM-C, JAXA. The GCOM-C satellite scheduled to be launched in early 2017.

  6. Spectral Ensemble Kalman Filters

    Czech Academy of Sciences Publication Activity Database

    Mandel, Jan; Kasanický, Ivan; Vejmelka, Martin; Fuglík, Viktor; Turčičová, Marie; Eben, Kryštof; Resler, Jaroslav; Juruš, Pavel

    2014-01-01

    Roč. 11, - (2014), EMS2014-446 [EMS Annual Meeting /14./ & European Conference on Applied Climatology (ECAC) /10./. 06.10.2014-10.10.2014, Prague] R&D Projects: GA ČR GA13-34856S Grant - others:NSF DMS-1216481 Institutional support: RVO:67985807 Keywords : data assimilation * spectral filter Subject RIV: DG - Athmosphere Sciences, Meteorology

  7. Mechanical spectral shift reactor

    International Nuclear Information System (INIS)

    Sherwood, D.G.; Wilson, J.F.; Salton, R.B.; Fensterer, H.F.

    1981-01-01

    A mechanical spectral shift reactor comprises apparatus for inserting and withdrawing water displacer elements from the reactor core for selectively changing the water-moderator volume in the core thereby changing the reactivity of the core. The apparatus includes drivemechanisms for moving the displacer elements relative to the core and guide mechanisms for guiding the displayer rods through the reactor vessel

  8. Mechanical spectral shift reactor

    International Nuclear Information System (INIS)

    Sherwood, D.G.; Wilson, J.F.; Salton, R.B.; Fensterer, H.F.

    1982-01-01

    A mechanical spectral shift reactor comprises apparatus for inserting and withdrawing water displacer elements from the reactor core for selectively changing the water-moderator volume in the core thereby changing the reactivity of the core. The apparatus includes drive mechanisms for moving the displacer elements relative to the core and guide mechanisms for guiding the displacer rods through the reactor vessel. (author)

  9. A Simple Spectral Observer

    Directory of Open Access Journals (Sweden)

    Lizeth Torres

    2018-05-01

    Full Text Available The principal aim of a spectral observer is twofold: the reconstruction of a signal of time via state estimation and the decomposition of such a signal into the frequencies that make it up. A spectral observer can be catalogued as an online algorithm for time-frequency analysis because is a method that can compute on the fly the Fourier transform (FT of a signal, without having the entire signal available from the start. In this regard, this paper presents a novel spectral observer with an adjustable constant gain for reconstructing a given signal by means of the recursive identification of the coefficients of a Fourier series. The reconstruction or estimation of a signal in the context of this work means to find the coefficients of a linear combination of sines a cosines that fits a signal such that it can be reproduced. The design procedure of the spectral observer is presented along with the following applications: (1 the reconstruction of a simple periodical signal, (2 the approximation of both a square and a triangular signal, (3 the edge detection in signals by using the Fourier coefficients, (4 the fitting of the historical Bitcoin market data from 1 December 2014 to 8 January 2018 and (5 the estimation of a input force acting upon a Duffing oscillator. To round out this paper, we present a detailed discussion about the results of the applications as well as a comparative analysis of the proposed spectral observer vis-à-vis the Short Time Fourier Transform (STFT, which is a well-known method for time-frequency analysis.

  10. Field Results from Three Campaigns to Validate the Performance of the Miniaturized Laser Heterodyne Radiometer (Mini-LHR) for Measuring Carbon Dioxide and Methane in the Atmospheric Column

    Science.gov (United States)

    Miller, J. Houston; Clarke, Greg B.; Melroy, Hilary; Ott, Lesley; Steel, Emily Wilson

    2014-01-01

    In a collaboration between NASA GSFC and GWU, a low-cost, surface instrument is being developed that can continuously monitor key carbon cycle gases in the atmospheric column: carbon dioxide (CO2) and methane (CH4). The instrument is based on a miniaturized, laser heterodyne radiometer (LHR) using near infrared (NIR) telecom lasers. Despite relatively weak absorption line strengths in this spectral region, spectrallyresolved atmospheric column absorptions for these two molecules fall in the range of 60-80% and thus sensitive and precise measurements of column concentrations are possible. In the last year, the instrument was deployed for field measurements at Park Falls, Wisconsin; Castle Airport near Atwater, California; and at the NOAA Mauna Loa Observatory in Hawaii. For each subsequent campaign, improvement in the figures of merit for the instrument has been observed. In the latest work the absorbance noise is approaching 0.002 optical density (OD) noise on a 1.8 OD signal. An overview of the measurement campaigns and the data retrieval algorithm for the calculation of column concentrations will be presented. For light transmission through the atmosphere, it is necessary to account for variation of pressure, temperature, composition, and refractive index through the atmosphere that are all functions of latitude, longitude, time of day, altitude, etc. For temperature, pressure, and humidity profiles with altitude we use the Modern-Era Retrospective Analysis for Research and Applications (MERRA) data. Spectral simulation is accomplished by integrating short-path segments along the trajectory using the SpecSyn spectral simulation suite developed at GW. Column concentrations are extracted by minimizing residuals between observed and modeled spectrum using the Nelder-Mead simplex algorithm. We will also present an assessment of uncertainty in the reported concentrations from assumptions made in the meteorological data, LHR instrument and tracker noise, and radio

  11. Spatiotemporal Variability of Earth's Radiation Balance Components from Russian Radiometer IKOR-M

    Science.gov (United States)

    Cherviakov, M.

    2016-12-01

    The radiometer IKOR-M was created in National Research Saratov State University for satellite monitoring of the outgoing reflected short-wave radiation, which is one of the components of Earth's radiation budget. Such information can be used in different models of long-term weather forecasts, in researches of climate change trends and in calculation of absorbed solar radiation values and albedo of the Earth-atmosphere system. The IKOR-M product archive is available online at all times. A searchable catalogue of data products is continually updated and users may search and download data products via the Earth radiation balance components research laboratory website as soon as they become available. Two series of measurements from two different IKOR-M are available. The first radiometer had worked from October 2009 to August 2014 and second - from August 2014 to the present. Therefore, there is a period when both radiometers work at the same time. Top-of-atmosphere fluxes deduced from the "Meteor-M" No 1 measurement in August, 2014 show very good agreement with the fluxes determined from "Meteor-M" No 2. The scale relationship of the IKOR-M radiometers on "Meteor - M" No 1 and No 2 satellites found by comparing of the global distribution maps for monthly averaged albedo values. The seasonal and interannual variations of OSR, albedo and ASR were discussed. The variations between SW radiation budget components seem to be within observational uncertainty and natural variability governed by cloudiness, water vapor and aerosol variations. It was assessed spatial and temporal variations of albedo and the absorbed solar radiation over different regions. Latitudinal distributions of albedo and ASR were estimated in more detail. Meridional cross sections over oceans and land were used separately for this estimation. It was shown that the albedo and ASR data received from the radiometer IKOR-M can be used to detect El Nino in the Pacific Ocean. The reported study was funded by

  12. Sensitivity of spectral indices to CO{sub 2} fluxes for several plant communities in a Sphagnum-dominated peatland

    Energy Technology Data Exchange (ETDEWEB)

    Letendre, J.; Poulin, M.; Rochefort, L. [Laval Univ., Quebec City, PQ (Canada). Dept. de Phytologie, Peatland Ecology and Research Group

    2008-07-01

    A study was conducted in which the relationship between spectral indices and carbon dioxide (CO{sub 2}) fluxes was tested for different communities in a Sphagnum-dominated peatland. This paper focused on the remote sensing approach that was used to directly link spectral indices to CO{sub 2} fluxes to highlight the potential of remote sensing for mapping the spatial distribution of CO{sub 2} fluxes. Carbon exchange in these ecosystems has become an environmental concern since peatlands play a key role in the global carbon cycle. A portable climate-controlled chamber was used to measure fluxes while simultaneously recording reflectance with a hand-held spectroradiometer. A laboratory experiment was also conducted to find a water-related index that most correlated with Sphagnum water content in order to regulate the normalized difference vegetation index (NDVI) values obtained in the field. The laboratory experiment showed a strong correlation between Sphagnum water content and all spectral indices, notably the water index (WI), normalized difference water index (NDWI), and relative depth index (RDI). The water index was chosen to regulate NDVI values. This paper described the indices that were tested in the field for CO{sub 2} flux estimations. NDVI alone was found to be a poor predictor of net ecosystem exchange. The relationship between CO{sub 2} fluxes and narrow band chlorophyll indices was reasonably well adjusted. It was concluded that the chlorophyll indices may be the most promising for mapping the spatial distribution of CO{sub 2} fluxes in the future. 62 refs., 2 tabs., 4 figs.

  13. Towards a long-term Science Exploitation Plan for the Sea and Land Surface Temperature Radiometer on Sentinel-3 and the Along-Track Scanning Radiometers

    Science.gov (United States)

    Remedios, John J.; Llewellyn-Jones, David

    2014-05-01

    The Sea and Land Surface Temperature Radiometer (SLSTR) on Sentinel-3 is the latest satellite instrument in a series of dual-angle optical and thermal sensors, the Along-Track Scanning Radiometers (ATSRs). Operating on Sentinel-3, the SLSTR has a number of significant improvements compared to the original ATSRs including wider swaths for nadir and dual angles, emphasis on all surface temperature domains, dedicated fire channels and additional cloud channels. The SLSTR therefore provides some excellent opportunities to extend science undertaken with the ATSRs whilst also providing long-term data sets to investigate climate change. The European Space Agency, together with the Department of Energy and Climate Change, sponsored the production of an Exploitation Plan for the ATSRs. In the last year, this been extended to cover the SLSTR also. The plan enables UK and European member states to plan activities related to SLSTR in a long-term context. Covering climate change, oceanography, land surface, atmosphere and cryosphere science, particular attention is paid to the exploitation of long-term data sets. In the case of SLSTR, relevant products include sea, land, lake and ice surface temperatures; aerosols and clouds; fires and gas flares; land surface reflectances. In this presentation, the SLSTR and ATSR science Exploitation Plan will be outlined with emphasis on SLSTR science opportunities, on appropriate co-ordinating mechanisms and on example implementation plans. Particular attention will be paid to the challenges of linking ATSR records with SLSTR to provide consistent long-term data sets, and on the international context of such data sets. The exploitation plan approach to science may prove relevant and useful for other Sentinel instruments.

  14. Hybrid spectral CT reconstruction.

    Directory of Open Access Journals (Sweden)

    Darin P Clark

    Full Text Available Current photon counting x-ray detector (PCD technology faces limitations associated with spectral fidelity and photon starvation. One strategy for addressing these limitations is to supplement PCD data with high-resolution, low-noise data acquired with an energy-integrating detector (EID. In this work, we propose an iterative, hybrid reconstruction technique which combines the spectral properties of PCD data with the resolution and signal-to-noise characteristics of EID data. Our hybrid reconstruction technique is based on an algebraic model of data fidelity which substitutes the EID data into the data fidelity term associated with the PCD reconstruction, resulting in a joint reconstruction problem. Within the split Bregman framework, these data fidelity constraints are minimized subject to additional constraints on spectral rank and on joint intensity-gradient sparsity measured between the reconstructions of the EID and PCD data. Following a derivation of the proposed technique, we apply it to the reconstruction of a digital phantom which contains realistic concentrations of iodine, barium, and calcium encountered in small-animal micro-CT. The results of this experiment suggest reliable separation and detection of iodine at concentrations ≥ 5 mg/ml and barium at concentrations ≥ 10 mg/ml in 2-mm features for EID and PCD data reconstructed with inherent spatial resolutions of 176 μm and 254 μm, respectively (point spread function, FWHM. Furthermore, hybrid reconstruction is demonstrated to enhance spatial resolution within material decomposition results and to improve low-contrast detectability by as much as 2.6 times relative to reconstruction with PCD data only. The parameters of the simulation experiment are based on an in vivo micro-CT experiment conducted in a mouse model of soft-tissue sarcoma. Material decomposition results produced from this in vivo data demonstrate the feasibility of distinguishing two K-edge contrast agents with

  15. Hybrid spectral CT reconstruction

    Science.gov (United States)

    Clark, Darin P.

    2017-01-01

    Current photon counting x-ray detector (PCD) technology faces limitations associated with spectral fidelity and photon starvation. One strategy for addressing these limitations is to supplement PCD data with high-resolution, low-noise data acquired with an energy-integrating detector (EID). In this work, we propose an iterative, hybrid reconstruction technique which combines the spectral properties of PCD data with the resolution and signal-to-noise characteristics of EID data. Our hybrid reconstruction technique is based on an algebraic model of data fidelity which substitutes the EID data into the data fidelity term associated with the PCD reconstruction, resulting in a joint reconstruction problem. Within the split Bregman framework, these data fidelity constraints are minimized subject to additional constraints on spectral rank and on joint intensity-gradient sparsity measured between the reconstructions of the EID and PCD data. Following a derivation of the proposed technique, we apply it to the reconstruction of a digital phantom which contains realistic concentrations of iodine, barium, and calcium encountered in small-animal micro-CT. The results of this experiment suggest reliable separation and detection of iodine at concentrations ≥ 5 mg/ml and barium at concentrations ≥ 10 mg/ml in 2-mm features for EID and PCD data reconstructed with inherent spatial resolutions of 176 μm and 254 μm, respectively (point spread function, FWHM). Furthermore, hybrid reconstruction is demonstrated to enhance spatial resolution within material decomposition results and to improve low-contrast detectability by as much as 2.6 times relative to reconstruction with PCD data only. The parameters of the simulation experiment are based on an in vivo micro-CT experiment conducted in a mouse model of soft-tissue sarcoma. Material decomposition results produced from this in vivo data demonstrate the feasibility of distinguishing two K-edge contrast agents with a spectral

  16. Noncommutativity from spectral flow

    Energy Technology Data Exchange (ETDEWEB)

    Heinzl, Thomas; Ilderton, Anton [School of Mathematics and Statistics, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

    2007-07-27

    We investigate the transition from second- to first-order systems. Quantum mechanically, this transforms configuration space into phase space and hence introduces noncommutativity in the former. This transition may be described in terms of spectral flow. Gaps in the energy or mass spectrum may become large which effectively truncates the available state space. Using both operator and path integral languages we explicitly discuss examples in quantum mechanics (light-front) quantum field theory and string theory.

  17. Mechanical spectral shift reactor

    International Nuclear Information System (INIS)

    Wilson, J.F.; Sherwood, D.G.

    1982-01-01

    A mechanical spectral shift reactor comprises a reactive core having fuel assemblies accommodating both water displacer elements and neutron absorbing control rods for selectively changing the volume of water-moderator in the core. The fuel assemblies with displacer and control rods are arranged in alternating fashion so that one displacer element drive mechanism may move displacer elements in more than one fuel assembly without interfering with the movement of control rods of a corresponding control rod drive mechanisms. (author)

  18. Speech recognition from spectral dynamics

    Indian Academy of Sciences (India)

    Carrier nature of speech; modulation spectrum; spectral dynamics ... the relationships between phonetic values of sounds and their short-term spectral envelopes .... the number of free parameters that need to be estimated from training data.

  19. Applying Advances in GPM Radiometer Intercalibration and Algorithm Development to a Long-Term TRMM/GPM Global Precipitation Dataset

    Science.gov (United States)

    Berg, W. K.

    2016-12-01

    The Global Precipitation Mission (GPM) Core Observatory, which was launched in February of 2014, provides a number of advances for satellite monitoring of precipitation including a dual-frequency radar, high frequency channels on the GPM Microwave Imager (GMI), and coverage over middle and high latitudes. The GPM concept, however, is about producing unified precipitation retrievals from a constellation of microwave radiometers to provide approximately 3-hourly global sampling. This involves intercalibration of the input brightness temperatures from the constellation radiometers, development of an apriori precipitation database using observations from the state-of-the-art GPM radiometer and radars, and accounting for sensor differences in the retrieval algorithm in a physically-consistent way. Efforts by the GPM inter-satellite calibration working group, or XCAL team, and the radiometer algorithm team to create unified precipitation retrievals from the GPM radiometer constellation were fully implemented into the current version 4 GPM precipitation products. These include precipitation estimates from a total of seven conical-scanning and six cross-track scanning radiometers as well as high spatial and temporal resolution global level 3 gridded products. Work is now underway to extend this unified constellation-based approach to the combined TRMM/GPM data record starting in late 1997. The goal is to create a long-term global precipitation dataset employing these state-of-the-art calibration and retrieval algorithm approaches. This new long-term global precipitation dataset will incorporate the physics provided by the combined GPM GMI and DPR sensors into the apriori database, extend prior TRMM constellation observations to high latitudes, and expand the available TRMM precipitation data to the full constellation of available conical and cross-track scanning radiometers. This combined TRMM/GPM precipitation data record will thus provide a high-quality high

  20. Understanding Soliton Spectral Tunneling as a Spectral Coupling Effect

    DEFF Research Database (Denmark)

    Guo, Hairun; Wang, Shaofei; Zeng, Xianglong

    2013-01-01

    Soliton eigenstate is found corresponding to a dispersive phase profile under which the soliton phase changes induced by the dispersion and nonlinearity are instantaneously counterbalanced. Much like a waveguide coupler relying on a spatial refractive index profile that supports mode coupling...... between channels, here we suggest that the soliton spectral tunneling effect can be understood supported by a spectral phase coupler. The dispersive wave number in the spectral domain must have a coupler-like symmetric profile for soliton spectral tunneling to occur. We show that such a spectral coupler...