Sample records for syringe calibration factors

  1. Syringe confiscation as an HIV risk factor: the public health implications of arbitrary policing in Tijuana and Ciudad Juarez, Mexico.

    PubMed

    Beletsky, Leo; Lozada, Remedios; Gaines, Tommi; Abramovitz, Daniela; Staines, Hugo; Vera, Alicia; Rangel, Gudelia; Arredondo, Jaime; Strathdee, Steffanie A

    2013-04-01

    Female sex workers who inject drugs (FSW-IDUs) face elevated risk for HIV/STIs and constitute a key population for public health prevention. Through direct and indirect pathways including human rights violations, policing practices like syringe confiscation can compound FSW-IDU health risk and facilitate the spread of disease. We studied correlates of experiencing syringe confiscation among FSW-IDUs in northern Mexico, where formal policy allows for syringes to be available over the counter without a prescription, but police practices are often at odds with the law. FSW-IDUs reporting recent syringe sharing and unprotected sex with clients in Tijuana and Ciudad Juarez were administered surveys and HIV/STI testing. Logistic regression was used to identify correlates of syringe confiscation. Among 624 respondent FSW-IDUs, prevalence of syringe confiscation in the last 6 months was 48%. The following factors were positively associated with syringe confiscation: testing positive for HIV (adjusted odds ratio [aOR]?=?2.54, 95% confidence interval [CI]?=?1.11-5.80), reporting sexual abuse by police (aOR?=?12.76, 95% CI?=?6.58-24.72), engaging in groin injection (aOR?=?1.84, 95% CI?=?1.15-2.93), injecting in public (aOR?=?1.64; 95% CI?=?1.14-2.36), and obtaining syringes from pharmacies (aOR?=?1.54; 95% CI?=?1.06-2.23). Higher education level was negatively associated with syringe confiscation (aOR?=?0.92, 95% CI?=?0.87-0.98) as was frequent injection with clients within the last month (aOR?=?0.64, 95% CI?=?0.44-0.94). This analysis adds to the body of evidence linking unauthorized law enforcement actions targeting high-risk groups with HIV and other adverse health outcomes. Using a public health lens to conceptualize abuse as a structural risk factor, we advocate for multi-prong prevention, systematic monitoring, and evidence-based intervention response to deleterious police practices. PMID:22806453

  2. Social and political factors predicting the presence of syringe exchange programs in 96 US metropolitan areas.

    PubMed

    Tempalski, Barbara; Flom, Peter L; Friedman, Samuel R; Des Jarlais, Don C; Friedman, Judith J; McKnight, Courtney; Friedman, Risa

    2007-03-01

    Community activism can be important in shaping public health policies. For example, political pressure and direct action from grassroots activists have been central to the formation of syringe exchange programs (SEPs) in the United States. We explored why SEPs are present in some localities but not others, hypothesizing that programs are unevenly distributed across geographic areas as a result of political, socioeconomic, and organizational characteristics of localities, including needs, resources, and local opposition. We examined the effects of these factors on whether SEPs were present in different US metropolitan statistical areas in 2000. Predictors of the presence of an SEP included percentage of the population with a college education, the existence of local AIDS Coalition to Unleash Power (ACT UP) chapters, and the percentage of men who have sex with men in the population. Need was not a predictor. PMID:17267732

  3. Syringe sociology.

    PubMed

    Vitellone, Nicole

    2015-06-01

    In this article I consider the impact of social epistemologies for understanding the object of the syringe. My aim is to examine the process through which the syringe transforms from an injecting device to a tool of social and political inquiry. Paying particular attention to the uses of Foucault, Becker, Bourdieu, Freud and Latour in empirical studies of injecting heroin use, I examine the sociology of the syringe through the lens of habit and habitus, discourse and deviance, mourning and melancholia, attachment and agencement. In pursuing the theory behind the object my goal is to address a sociological object in the making. In so doing I show how the syringe has been significant for social research, social theory, and sociology. It is the difference the object makes that this article seeks to describe. In tracing the epistemology of the syringe I show how the object is important not just for knowledge of addiction but sociology itself. PMID:26072683

  4. SWIR calibration of Spectralon reflectance factor

    Microsoft Academic Search

    Georgi T. Georgiev; James J. Butler; Catherine Cooksey; Leibo Ding; Kurtis J. Thome

    2011-01-01

    Satellite instruments operating in the reflective solar wavelength region require accurate and precise determination of the Bidirectional Reflectance Factor (BRF) of laboratory-based diffusers used in their pre-flight and on-orbit radiometric calibrations. BRF measurements are required throughout the reflected-solar spectrum from the ultraviolet through the shortwave infrared. Spectralon diffusers are commonly used as a reflectance standard for bidirectional and hemispherical geometries.

  5. SWIR calibration of Spectralon reflectance factor

    NASA Astrophysics Data System (ADS)

    Georgiev, Georgi T.; Butler, James J.; Cooksey, Catherine; Ding, Leibo; Thome, Kurtis J.

    2011-11-01

    Satellite instruments operating in the reflective solar wavelength region require accurate and precise determination of the Bidirectional Reflectance Factor (BRF) of laboratory-based diffusers used in their pre-flight and on-orbit radiometric calibrations. BRF measurements are required throughout the reflected-solar spectrum from the ultraviolet through the shortwave infrared. Spectralon diffusers are commonly used as a reflectance standard for bidirectional and hemispherical geometries. The Diffuser Calibration Laboratory (DCaL) at NASA's Goddard Space Flight Center is a secondary calibration facility with reflectance measurements traceable to those made by the Spectral Tri-function Automated Reference Reflectometer (STARR) facility at the National Institute of Standards and Technology (NIST). For more than two decades, the DCaL has provided numerous NASA projects with BRF data in the ultraviolet (UV), visible (VIS) and the Near InfraRed (NIR) spectral regions. Presented in this paper are measurements of BRF from 1475 nm to 1625 nm obtained using an indium gallium arsenide detector and a tunable coherent light source. The sample was a 50.8 mm (2 in) diameter, 99% white Spectralon target. The BRF results are discussed and compared to empirically generated data from a model based on NIST certified values of 6°directional-hemispherical spectral reflectance factors from 900 nm to 2500 nm. Employing a new NIST capability for measuring bidirectional reflectance using a cooled, extended InGaAs detector, BRF calibration measurements of the same sample were also made using NIST's STARR from 1475 nm to 1625 nm at an incident angle of 0° and at viewing angle of 45°. The total combined uncertainty for BRF in this ShortWave Infrared (SWIR) range is less than 1%. This measurement capability will evolve into a BRF calibration service in SWIR region in support of NASA remote sensing missions.

  6. Syringe-injectable electronics.

    PubMed

    Liu, Jia; Fu, Tian-Ming; Cheng, Zengguang; Hong, Guosong; Zhou, Tao; Jin, Lihua; Duvvuri, Madhavi; Jiang, Zhe; Kruskal, Peter; Xie, Chong; Suo, Zhigang; Fang, Ying; Lieber, Charles M

    2015-07-01

    Seamless and minimally invasive three-dimensional interpenetration of electronics within artificial or natural structures could allow for continuous monitoring and manipulation of their properties. Flexible electronics provide a means for conforming electronics to non-planar surfaces, yet targeted delivery of flexible electronics to internal regions remains difficult. Here, we overcome this challenge by demonstrating the syringe injection (and subsequent unfolding) of sub-micrometre-thick, centimetre-scale macroporous mesh electronics through needles with a diameter as small as 100??m. Our results show that electronic components can be injected into man-made and biological cavities, as well as dense gels and tissue, with >90% device yield. We demonstrate several applications of syringe-injectable electronics as a general approach for interpenetrating flexible electronics with three-dimensional structures, including (1) monitoring internal mechanical strains in polymer cavities, (2) tight integration and low chronic immunoreactivity with several distinct regions of the brain, and (3) in vivo multiplexed neural recording. Moreover, syringe injection enables the delivery of flexible electronics through a rigid shell, the delivery of large-volume flexible electronics that can fill internal cavities, and co-injection of electronics with other materials into host structures, opening up unique applications for flexible electronics. PMID:26053995

  7. Calibration factors for the SNOOPY NP-100 neutron dosimeter

    NASA Astrophysics Data System (ADS)

    Moscu, D. F.; McNeill, F. E.; Chase, J.

    2007-10-01

    Within CANDU nuclear power facilities, only a small fraction of workers are exposed to neutron radiation. For these individuals, roughly 4.5% of the total radiation equivalent dose is the result of exposure to neutrons. When this figure is considered across all workers receiving external exposure of any kind, only 0.25% of the total radiation equivalent dose is the result of exposure to neutrons. At many facilities, the NP-100 neutron dosimeter, manufactured by Canberra Industries Incorporated, is employed in both direct and indirect dosimetry methods. Also known as "SNOOPY", these detectors undergo calibration, which results in a calibration factor relating the neutron count rate to the ambient dose equivalent rate, using a standard Am-Be neutron source. Using measurements presented in a technical note, readings from the dosimeter for six different neutron fields in six source-detector orientations were used, to determine a calibration factor for each of these sources. The calibration factor depends on the neutron energy spectrum and the radiation weighting factor to link neutron fluence to equivalent dose. Although the neutron energy spectra measured in the CANDU workplace are quite different than that of the Am-Be calibration source, the calibration factor remains constant - within acceptable limits - regardless of the neutron source used in the calibration; for the specified calibration orientation and current radiation weighting factors. However, changing the value of the radiation weighting factors would result in changes to the calibration factor. In the event of changes to the radiation weighting factors, it will be necessary to assess whether a change to the calibration process or resulting calibration factor is warranted.

  8. Auto-disable syringes for immunization: issues in technology transfer.

    PubMed

    Lloyd, J S; Milstien, J B

    1999-01-01

    WHO and its partners recommend the use of auto-disable syringes, "bundled" with the supply of vaccines when donor dollars are used, in all mass immunization campaigns, and also strongly advocate their use in routine immunization programmes. Because of the relatively high price of auto-disable syringes, WHO's Technical Network for Logistics in Health recommends that activities be initiated to encourage the transfer of production technology for these syringes as a means of promoting their use and enhancing access to the technology. The present article examines factors influencing technology transfer, including feasibility, corporate interest, cost, quality assurance, intellectual property considerations, and probable time frames for implementation. Technology transfer activities are likely to be complex and difficult, and may not result in lower prices for syringes. Guidelines are offered on technology transfer initiatives for auto-disable syringes to ensure the quality of the product, the reliability of the supply, and the feasibility of the technology transfer activity itself. PMID:10680248

  9. 21 CFR 872.6770 - Cartridge syringe.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Identification. A cartridge syringe is a device intended to inject...The device consists of a metal syringe body into which a disposable...is placed. After attaching a needle to the syringe body and activating the...

  10. 21 CFR 872.6770 - Cartridge syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Identification. A cartridge syringe is a device intended to inject...The device consists of a metal syringe body into which a disposable...is placed. After attaching a needle to the syringe body and activating the...

  11. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Piston syringe. 880.5860 Section 880...Devices § 880.5860 Piston syringe. (a) Identification. A piston syringe is a device intended...a hypodermic single lumen needle. The device is used to...

  12. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 false Piston syringe. 880.5860 Section 880...Devices § 880.5860 Piston syringe. (a) Identification. A piston syringe is a device intended...a hypodermic single lumen needle. The device is used to...

  13. Automated application of calibration factors on telemetered data

    SciTech Connect

    Kalibjian, J.R.; Voss, T.J.; Yio, J.J.

    1993-04-26

    A long standing problem in telemetry post processing is the application of correct calibration factors to telemetered data generated on a system which has had a history of hardware changes. These calibration problems become most exacerbated when old test data is being examined and there is uncertainty as to hardware configuration at the time of the test. In this paper a mechanism for introducing a high degree of reliability in the application of calibration factors is described in an implementation done for Brilliant Pebbles Flight Experiment Three (FE-3).

  14. Situational factors influencing drug injecting, risk reduction and syringe exchange in Togliatti City, Russian Federation: a qualitative study of micro risk environment

    Microsoft Academic Search

    Tim Rhodes; Larissa Mikhailova; Anya Sarang; Catherine M. Lowndes; Andrey Rylkov; Mikhail Khutorskoy; Adrian Renton

    2003-01-01

    We undertook a qualitative study to explore the micro-environment of drug injecting, risk reduction and syringe exchange practices among injecting drug users (IDUs) in Togliatti City, Russia. Semi-structured qualitative interviews (n=57) were undertaken with current IDUs in May 2001. Findings highlight a recent transition away from hanka (a home-produced liquid opiate derived from opium poppy) towards the injection of heroin

  15. Experiments with Disposable Hypodermic Syringes.

    ERIC Educational Resources Information Center

    Clayton, G. T.; And Others

    1988-01-01

    Lists five experiments or demonstrations involving hypodermic syringes. The titles of experiments are Boyle's Law, Charles' Law, Atmospheric Pressure, Expansion of Gases, and Boiling at Reduced Pressure. Provides a list of materials, the typical data, and graphs where appropriate. (YP)

  16. Fabrication of Syringe-Shaped GaN Nanorods

    NASA Astrophysics Data System (ADS)

    Xue, Cheng-Shan; Wu, Yu-Xin; Zhuang, Hui-Zhao; Tian, De-Heng; Liu, Yi-An; He, Jian-Ting; Ai, Yu-Jie; Sun, Li-Li; Wang, Fu-Xue; Cao, Yu-Ping

    2006-03-01

    Syringe-shaped GaN nanorods are synthesized on Si(111) substrates by annealing sputtered Ga2O3/BN films under flowing ammonia at temperature of 950°C. Most of the nanorods consist of a main rod and a top needle, looking like a syringe. X-ray diffraction and selected-area electron diffraction confirm that the syringe-shaped nanorods are hexagonal wurtzite GaN. Scanning electron microscopy and high-resolution transmission electron microscopy reveal that these nanorods are as long as several micrometres, with diameters ranging from 100 to 300 nm. In addition to the BN intermediate layer, the proper annealing temperature has been demonstrated to be a crucial factor for the growth of syringe-shaped nanorods by this method.

  17. Development of syringe pump assisted headspace sampler.

    PubMed

    Go, Un Jeong; Eom, In-Yong

    2014-09-26

    This report describes a new platform for headspace sampling technique, i.e. a syringe pump assisted headspace sampler (SPHS). The stand type pump's syringe itself was used as a sealed sample vial and a needle trap device (NTD) was adopted as a miniaturized sorbent tube. The NTD was directly used to inject trapped VOCs into a gas chromatograph. The proposed sampler was designed to take a whole headspace volume instead of a portion of it so as to enhance easily the extraction efficiency. The performance of the SPHS-NTD system was evaluated and compared with the solid-phase microextraction (SPME) with a static headspace (HS) sampling technique. Calibration curves were obtained for aqueous TEX (toluene, ethylbenzene, and o-xylene) solutions in the concentration range of ?0.1-45 ng/mL. The calculated limit of detections (LOD, S/N=3) for TEX were 0.13 ng/mL or less. This SPHS-NTD was successfully applied to analyze aqueous TEX in river water samples and showed highly good recovery ranged from 97.2% to 105.8% for all tested VOCs. PMID:25155066

  18. jasonSWIR Calibration of Spectralon Reflectance Factor

    NASA Technical Reports Server (NTRS)

    Georgiev, Georgi T.; Butler, James J.; Cooksey, Cahterine; Ding, Leibo; Thome, Kurtis J.

    2011-01-01

    Satellite instruments operating in the reflective solar wavelength region require accurate and precise determination of the Bidirectional Reflectance Factor (BRF) of laboratory-based diffusers used in their pre-flight and on-orbit radiometric calibrations. BRF measurements are required throughout the reflected-solar spectrum from the ultraviolet through the shortwave infrared. Spectralon diffusers are commonly used as a reflectance standard for bidirectional and hemispherical geometries. The Diffuser Calibration Laboratory (DCaL) at NASA's Goddard Space Flight Center is a secondary calibration facility with reflectance measurements traceable to those made by the Spectral Tri-function Automated Reference Reflectometer (STARR) facility at the National Institute of Standards and Technology (NIST). For more than two decades, the DCaL has provided numerous NASA projects with BRF data in the ultraviolet (UV), visible (VIS) and the Near infraRed (NIR) spectral regions. Presented in this paper are measurements of BRF from 1475nm to 1625nm obtained using an indium gallium arsenide detector and a tunable coherent light source. The sample was a 2 inch diameter, 99% white Spectralon target. The BRF results are discussed and compared to empirically generated data from a model based on NIST certified values of 6deg directional/hemispherical spectral reflectance factors from 900nm to 2500nm. Employing a new NIST capability for measuring bidirectional reflectance using a cooled, extended InGaAs detector, BRF calibration measurements of the same sample were also made using NIST's STARR from 1475nm to 1625nm at an incident angle of 0deg and at viewing angles of 40deg, 45deg, and 50deg. The total combined uncertainty for BRF in this ShortWave Infrared (SWIR) range is less than 1%. This measurement capability will evolve into a BRF calibration service in SWIR region in support of NASA remote sensing missions. Keywords: BRF, BRDF, Calibration, Spectralon, Reflectance, Remote Sensing.

  19. Syringe drivers: incorrect selection of syringe type from the syringe menu may result in significant errors in drug delivery.

    PubMed

    Tooke, L J; Howell, L

    2014-07-01

    There have been many reported adverse incidents due to syringe driver use, most of which have been attributable to human error. In this paper we present a previously unreported, but potentially widespread practice which may result in significant over or under-delivery of medication. Even with the naked eye it is evident that syringes of equal volume have different dimensions and to quantify this we sectioned a range of syringes and measured the inner and outer dimensions. Extensive menus for syringe brand and volumes are available on syringe drivers, offering users greater flexibility. However, this feature also allows users to select an incorrect syringe brand with potential consequences for drug delivery. We measured outputs under all selectable permutations, to determine the degree of fluid delivery variation and discovered inaccuracies in volumes ranging from 10% under-delivery to 24% over-delivery. There is a wide variation in syringe metrics and complex syringe menus may increase errors, resulting in significant under or over-delivery of medication. Availability of more than one brand of syringe in a clinical area increases the risk of adverse drug delivery events. Systems need to be implemented to minimise the risk of adverse events. PMID:24967761

  20. Determination of a calibration factor for the nondestructive assay of Guidant 32P brachytherapy sources

    Microsoft Academic Search

    R Collé; B. E Zimmerman; C. G Soares; B. M Coursey

    1999-01-01

    A calibration factor (`dial setting') for the nondestructive assay of Guidant TiNi-encapsulated 32P intravascular brachytherapy wire sources has been determined for measurements with the Capintec CRC-12 (sic. `dose calibrator') ionization chamber. The calibration factor was derived from ionization current measurements with the CRC-12 followed by very quantitative, destructive assays of the 32P content in two sources.

  1. Don't Throw Away Syringes!

    ERIC Educational Resources Information Center

    John, E.

    1975-01-01

    Describes a variety of laboratory experiments including carbon dioxide reduction, animal respiration, atmospheric pressure determination, and others, that can be performed using discarded syringes. (GS)

  2. Safe Syringe Disposal is Related to Safe Syringe Access among HIV-positive Injection Drug Users

    Microsoft Academic Search

    Phillip O. Coffin; Mary H. Latka; Carl Latkin; Yingfeng Wu; David W. Purcell; Lisa Metsch; Cynthia Gomez; Marc N. Gourevitch

    2007-01-01

    We evaluated the effect of syringe acquisition on syringe disposal among HIV-positive injection drug users (IDUs) in Baltimore,\\u000a New York City, and San Francisco (N = 680; mean age 42 years, 62% male, 59% African-American, 21% Hispanic, 12% White). Independent predictors of safe disposal\\u000a were acquiring syringes through a safe source and ever visiting a syringe exchange program. Weaker predictors included living\\u000a in

  3. Use and misuse of syringes in anaesthesia

    Microsoft Academic Search

    Martin R. Lessard; Claude A. Trépanier

    1997-01-01

    Using data from the literature, a fairly accurate estimate of the risk of transmission of bloodborne infections associated with the reuse of syringes in anaesthesia can be made. In anaesthesia, most of the time, syringes are used to administer medications into injection ports or three-way stopcocks of iv tubing that might be contaminated with the patient's blood. That situation differs

  4. The coated antiseptic tip (CAT) syringe.

    PubMed

    Mariyaselvam, Maryanne; Hodges, Emily; Richardson, James; Steel, Alistair; Moondi, Parvez; Young, Peter

    2015-07-01

    Catheter-related blood stream infections (CR-BSI) account for 30% of healthcare acquired infection (HAI). Colonization of connector hubs and contaminated syringes are thought to increase the risk of CR-BSI. The Coated Antiseptic Tip (CAT) syringe was developed to decontaminate connector hubs, thereby reducing the risk of CR-BSI. Needleless valves (n?=?20) and three-way connectors (n?=?20) were contaminated with common critical care pathogens. At hourly intervals, CAT syringes were inserted into the connector hubs and normal saline was injected through the connector. This was repeated with control (non-coated) syringes. The internal surface of the connector hubs were swabbed at t?=?0, t?=?1?h and t?=?4?h, inoculated onto blood agar plates and analysed by a blinded microbiologist. Growth was counted as the number of colony forming units. Baseline swabbing demonstrated 100% bacterial hub colonization in both connectors. The CAT syringe showed a significant reduction in CFU growth at 0 and 1?h compared with control syringes (p?syringe completely eliminated bacterial growth in both of the connector hubs. The CAT syringe can effectively disinfect both three-way and needleless connectors. PMID:25970696

  5. 21 CFR 880.6920 - Syringe needle introducer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Syringe needle introducer. 880.6920 Section...Miscellaneous Devices § 880.6920 Syringe needle introducer. (a) Identification. A syringe needle introducer is a device that...

  6. 21 CFR 880.6920 - Syringe needle introducer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Syringe needle introducer. 880.6920 Section...Miscellaneous Devices § 880.6920 Syringe needle introducer. (a) Identification. A syringe needle introducer is a device that...

  7. The association of syringe type and syringe cleaning with HCV infection among IDUs in Budapest, Hungary

    Microsoft Academic Search

    V. Anna Gyarmathy; Alan Neaigus; Mary M. Mitchell; Eszter Ujhelyi

    2009-01-01

    We assessed whether syringe type, syringe cleaning and distributive syringe sharing were associated with self-reported and laboratory-confirmed HCV infection among Hungarian IDUs. Injecting drug users (N=215) were recruited from non-treatment settings in Budapest, Hungary between October 2005 and December 2006. Multivariate logistic regression models identified correlates of self-report of being HCV infected and testing positive for HCV. While 37% tested

  8. 21 CFR 872.6770 - Cartridge syringe.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...6770 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6770 Cartridge syringe. (a) Identification. A...

  9. 21 CFR 872.6770 - Cartridge syringe.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...6770 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6770 Cartridge syringe. (a) Identification. A...

  10. Physics of Friction in Disposable Plastic Syringes

    NASA Astrophysics Data System (ADS)

    Liebmann-Vinson, A.; Vogler, E. A.; Martin, D. A.; Montgomery, D. B.; Sugg, H. W.; Monahan, L. A.

    1997-03-01

    Nosocomial applications of disposable plastic syringes demand excellent frictional behavior with no stick-slip over a broad velocity range and, simultaneously, a tight seal between stopper and barrel. However, when used in syringe pumps at slow injection speeds, stick-slip motion is frequently observed and high "break-out" forces are often necessary to initiate plunger movement after extended storage times. We have traced this frictional behavior to a velocity-dependent interaction between the elastomeric stopper and the plastic syringe barrel mediated by the syringe lubricant, almost universally a polydimethyl siloxane fluid. Lubricant properties were altered by crosslinking the surface of the silicone oil in an oxygen plasma. Changes in surface chemistry and morphology of the crosslinked oil were correlated with changes in frictional performance.

  11. SP100i Syringe Pump WORLD PRECISION INSTRUMENTS 15

    E-print Network

    Kleinfeld, David

    SP100i Syringe Pump WORLD PRECISION INSTRUMENTS 15 INSTRUCTION MANUAL Serial No._____________________ 8/94 World Precision Instruments, Inc. SP100i Syringe Pump Digital Infusion Syringe Pump #12;SP100i Syringe Pump WORLD PRECISION INSTRUMENTS 1 Contents GENERAL DESCRIPTION

  12. Calibration

    NASA Astrophysics Data System (ADS)

    Kunze, Hans-Joachim

    Commercial spectrographic systems are usually supplied with some wave-length calibration, but it is essential that the experimenter performs his own calibration for reliable measurements. A number of sources emitting well-known emission lines are available, and the best values of their wavelengths may be taken from data banks accessible on the internet. Data have been critically evaluated for many decades by the National Institute of Standards and Technology (NIST) of the USA [13], see also p. 3. Special data bases have been established by the astronomy and fusion communities (Appendix B).

  13. Syringe and Needle Size, Syringe Type, Vacuum Generation, and Needle Control in Aspiration Procedures

    SciTech Connect

    Haseler, Luke J., E-mail: l.haseler@griffith.edu.au [Griffith University, Heart Foundation Research Centre, Griffith Health Institute (Australia); Sibbitt, Randy R., E-mail: THESIBB2@aol.com [Montana Interventional and Dgnstc Radiation (United States); Sibbitt, Wilmer L., E-mail: wsibbitt@salud.unm.edu [University of New Mexico Health Sciences Center, Department of Internal Medicine (United States); Michael, Adrian A., E-mail: adrian_a_michael@yahoo.com [Texas Tech University Health Sciences Center, Department of Internal Medicine (United States); Gasparovic, Charles M., E-mail: chuck@unm.edu [University of New Mexico Health Sciences Center, MIND Institute at the University of New Mexico (United States); Bankhurst, Arthur D., E-mail: abankhurst@salud.unm.edu [University of New Mexico Health Sciences Center, Department of Internal Medicine (United States)

    2011-06-15

    Purpose: Syringes are used for diagnostic fluid aspiration and fine-needle aspiration biopsy in interventional procedures. We determined the benefits, disadvantages, and patient safety implications of syringe and needle size on vacuum generation, hand force requirements, biopsy/fluid yield, and needle control during aspiration procedures. Materials and Methods: Different sizes (1, 3, 5, 10, and 20 ml) of the conventional syringe and aspirating mechanical safety syringe, the reciprocating procedure device, were studied. Twenty operators performed aspiration procedures with the following outcomes measured: (1) vacuum (torr), (2) time to vacuum (s), (3) hand force to generate vacuum (torr-cm{sup 2}), (4) operator difficulty during aspiration, (5) biopsy yield (mg), and (6) operator control of the needle tip position (mm). Results: Vacuum increased tissue biopsy yield at all needle diameters (P < 0.002). Twenty-milliliter syringes achieved a vacuum of -517 torr but required far more strength to aspirate, and resulted in significant loss of needle control (P < 0.002). The 10-ml syringe generated only 15% less vacuum (-435 torr) than the 20-ml device and required much less hand strength. The mechanical syringe generated identical vacuum at all syringe sizes with less hand force (P < 0.002) and provided significantly enhanced needle control (P < 0.002). Conclusions: To optimize patient safety and control of the needle, and to maximize fluid and tissue yield during aspiration procedures, a two-handed technique and the smallest syringe size adequate for the procedure should be used. If precise needle control or one-handed operation is required, a mechanical safety syringe should be considered.

  14. Prevalence and predictors of transitions to and away from syringe exchange use over time in 3 US cities with varied syringe dispensing policies.

    PubMed

    Green, Traci C; Bluthenthal, Ricky N; Singer, Merrill; Beletsky, Leo; Grau, Lauretta E; Marshall, Patricia; Heimer, Robert

    2010-09-01

    Syringe exchange programs (SEPs) can reduce HIV risk among injecting drug users (IDUs) but their use may depend heavily on contextual factors such as local syringe policies. The frequency and predictors of transitioning over time to and from direct, indirect, and non-use of SEPs are unknown. We sought, over one year, to: (1) quantify and characterize transition probabilities of SEP attendance typologies; (2) identify factors associated with (a) change in typology, and (b) becoming and maintaining Direct SEP use; and (3) quantify and characterize transition probabilities of SEP attendance before and after changes in policy designed to increase access. Using data collected from 583 IDUs participating in a three-city cohort study of SEPs, we conducted a latent transition analysis and multinomial regressions. Three typologies were detected: Direct SEP users, Indirect SEP users and Isolated IDUs. Transitions to Direct SEP use were most prevalent. Factors associated with becoming or maintaining Direct SEP use were female sex, Latino ethnicity, fewer injections per syringe, homelessness, recruitment city, injecting speedballs (cocaine and heroin), and police contact involving drug paraphernalia possession. Similar factors influenced transitions in the syringe policy change analysis. Policy change cities experienced an increase in Indirect SEP users (43-51%) with little increased direct use (29-31%). We found that, over time, IDUs tended to become Direct SEP users. Policies improving syringe availability influenced SEP use by increasing secondary syringe exchange. Interactions with police around drug paraphernalia may encourage SEP use for some IDUs and may provide opportunities for other health interventions. PMID:20537814

  15. Prefilled syringes: An innovation in parenteral packaging

    PubMed Central

    Makwana, Sagar; Basu, Biswajit; Makasana, Yogita; Dharamsi, Abhay

    2011-01-01

    Parenteral administration of pharmaceutical products is one of the most popular methods used to produce quick onset of action and also 100% bioavailability. Main problem occurs with the parenteral drug delivery is lack of convenience, affordability, accuracy, sterility, safety etc. Such drawbacks with this delivery system makes it less preferable. Hence, all the disadvantages of these systems can be easily overcome by use of prefilled syringes. The objective of this review article is to provide information regarding prefilled syringes; it's method of preparation, direction to use, advantages, its future scope, and development. PMID:23071944

  16. Combination syringe provides air-free blood samples

    NASA Technical Reports Server (NTRS)

    Pool, S. L.

    1970-01-01

    Standard syringe and spinal needle are combined in unique manner to secure air-free blood samples. Combination syringe obtains air free samples because air bubbles become insignificant when samples greater than 1 cc are drawn.

  17. Open-Source Syringe Pump Library

    PubMed Central

    Wijnen, Bas; Hunt, Emily J.; Anzalone, Gerald C.; Pearce, Joshua M.

    2014-01-01

    This article explores a new open-source method for developing and manufacturing high-quality scientific equipment suitable for use in virtually any laboratory. A syringe pump was designed using freely available open-source computer aided design (CAD) software and manufactured using an open-source RepRap 3-D printer and readily available parts. The design, bill of materials and assembly instructions are globally available to anyone wishing to use them. Details are provided covering the use of the CAD software and the RepRap 3-D printer. The use of an open-source Rasberry Pi computer as a wireless control device is also illustrated. Performance of the syringe pump was assessed and the methods used for assessment are detailed. The cost of the entire system, including the controller and web-based control interface, is on the order of 5% or less than one would expect to pay for a commercial syringe pump having similar performance. The design should suit the needs of a given research activity requiring a syringe pump including carefully controlled dosing of reagents, pharmaceuticals, and delivery of viscous 3-D printer media among other applications. PMID:25229451

  18. Calibration CALIBRATION

    E-print Network

    Liskiewicz, Maciej

    65 Calibration CALIBRATION T. David Reed, Extension Agronomist, Tobacco Proper calibration of both the number of ounces colleted by 10 to obtain application rate in gal. per 1,000 sq. ft. Since greenhouse

  19. Factors affecting the repeatability of gamma camera calibration for quantitative imaging applications using a sealed source.

    PubMed

    Anizan, N; Wang, H; Zhou, X C; Wahl, R L; Frey, E C

    2015-02-01

    Several applications in nuclear medicine require absolute activity quantification of single photon emission computed tomography images. Obtaining a repeatable calibration factor that converts voxel values to activity units is essential for these applications. Because source preparation and measurement of the source activity using a radionuclide activity meter are potential sources of variability, this work investigated instrumentation and acquisition factors affecting repeatability using planar acquisition of sealed sources. The calibration factor was calculated for different acquisition and geometry conditions to evaluate the effect of the source size, lateral position of the source in the camera field-of-view (FOV), source-to-camera distance (SCD), and variability over time using sealed Ba-133 sources. A small region of interest (ROI) based on the source dimensions and collimator resolution was investigated to decrease the background effect. A statistical analysis with a mixed-effects model was used to evaluate quantitatively the effect of each variable on the global calibration factor variability. A variation of 1?cm in the measurement of the SCD from the assumed distance of 17?cm led to a variation of 1-2% in the calibration factor measurement using a small disc source (0.4?cm diameter) and less than 1% with a larger rod source (2.9?cm diameter). The lateral position of the source in the FOV and the variability over time had small impacts on calibration factor variability. The residual error component was well estimated by Poisson noise. Repeatability of better than 1% in a calibration factor measurement using a planar acquisition of a sealed source can be reasonably achieved. The best reproducibility was obtained with the largest source with a count rate much higher than the average background in the ROI, and when the SCD was positioned within 5?mm of the desired position. In this case, calibration source variability was limited by the quantum noise. PMID:25592130

  20. Direct calibration in megavoltage photon beams using Monte Carlo conversion factor: validation and clinical implications.

    PubMed

    Wright, Tracy; Lye, Jessica E; Ramanathan, Ganesan; Harty, Peter D; Oliver, Chris; Webb, David V; Butler, Duncan J

    2015-01-21

    The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has established a method for ionisation chamber calibrations using megavoltage photon reference beams. The new method will reduce the calibration uncertainty compared to a (60)Co calibration combined with the TRS-398 energy correction factor. The calibration method employs a graphite calorimeter and a Monte Carlo (MC) conversion factor to convert the absolute dose to graphite to absorbed dose to water. EGSnrc is used to model the linac head and doses in the calorimeter and water phantom. The linac model is validated by comparing measured and modelled PDDs and profiles. The relative standard uncertainties in the calibration factors at the ARPANSA beam qualities were found to be 0.47% at 6?MV, 0.51% at 10?MV and 0.46% for the 18?MV beam. A comparison with the Bureau International des Poids et Mesures (BIPM) as part of the key comparison BIPM.RI(I)-K6 gave results of 0.9965(55), 0.9924(60) and 0.9932(59) for the 6, 10 and 18?MV beams, respectively, with all beams within 1? of the participant average. The measured kQ values for an NE2571 Farmer chamber were found to be lower than those in TRS-398 but are consistent with published measured and modelled values. Users can expect a shift in the calibration factor at user energies of an NE2571 chamber between 0.4-1.1% across the range of calibration energies compared to the current calibration method. PMID:25565406

  1. Direct calibration in megavoltage photon beams using Monte Carlo conversion factor: validation and clinical implications

    NASA Astrophysics Data System (ADS)

    Wright, Tracy; Lye, Jessica E.; Ramanathan, Ganesan; Harty, Peter D.; Oliver, Chris; Webb, David V.; Butler, Duncan J.

    2015-01-01

    The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has established a method for ionisation chamber calibrations using megavoltage photon reference beams. The new method will reduce the calibration uncertainty compared to a 60Co calibration combined with the TRS-398 energy correction factor. The calibration method employs a graphite calorimeter and a Monte Carlo (MC) conversion factor to convert the absolute dose to graphite to absorbed dose to water. EGSnrc is used to model the linac head and doses in the calorimeter and water phantom. The linac model is validated by comparing measured and modelled PDDs and profiles. The relative standard uncertainties in the calibration factors at the ARPANSA beam qualities were found to be 0.47% at 6?MV, 0.51% at 10?MV and 0.46% for the 18?MV beam. A comparison with the Bureau International des Poids et Mesures (BIPM) as part of the key comparison BIPM.RI(I)-K6 gave results of 0.9965(55), 0.9924(60) and 0.9932(59) for the 6, 10 and 18?MV beams, respectively, with all beams within 1? of the participant average. The measured kQ values for an NE2571 Farmer chamber were found to be lower than those in TRS-398 but are consistent with published measured and modelled values. Users can expect a shift in the calibration factor at user energies of an NE2571 chamber between 0.4–1.1% across the range of calibration energies compared to the current calibration method.

  2. HIV Risk Behavior among Amphetamine Injectors at U.S. Syringe Exchange Programs

    ERIC Educational Resources Information Center

    Braine, Naomi; Des Jarlais, Don C.; Goldblatt, Cullen; Zadoretzky, Cathy; Turner, Charles

    2005-01-01

    The goal of this study was to compare HIV risk behaviors of amphetamine and non-amphetamine injectors at syringe exchange programs (SEP) in the United States and to identify factors associated with injection risk. This analysis is based on data from a random cross-section of participants at 13 SEPs in different parts of the country. All interviews…

  3. Correlates of syringe coverage for heroin injection in 35 large metropolitan areas in the US in which heroin is the dominant injected drug

    PubMed Central

    Tempalski, Barbara; Cooper, Hannah L.; Friedman, Samuel R.; Des Jarlais, Don C.; Brady, Joanne; Gostnell, Karla

    2009-01-01

    Background Scientific consensus holds that if, at the outset of the HIV/AIDS epidemic, injection drug users (IDUs) had had better access to sterile syringes, much of the epidemic among IDUs in the U.S. could have been prevented. In the context of preventing infectious diseases, 100% syringe coverage—that is, one sterile syringe per injector for each injection—is a public health goal. Notably, we know little about variations in syringe coverage within the U.S. and elsewhere, or about the social and political factors that might determine this coverage. Methods Using data from Holmberg (AJPH, 1996), the 1990 United States Census, the 2000 Beth Israel National Syringe Exchange Survey (n=72), and estimates of IDUs in metropolitan areas (MSAs); (Friedman et al., 2004), we explore the impact of (1) political factors (ACT UP, outreach, early syringe exchange programme (SEP) presence, men who have sex with men (MSM) per capita, drug arrests, and police per capita); (2) local resources for SEPs; and (3) indicators of socioeconomic inequality on SEP coverage. We define “syringe coverage” as the ratio of syringes distributed at SEPs to the number of syringes heroin injectors need in a year. We calculated the number of syringes heroin injectors need in a year by multiplying an estimate of the number of IDUs in each MSA by an estimate of the average number of times heroin injectors inject heroin per year (2.8 times per day times 365 days). In this analysis, the sample was limited to 35 MSAs in which the primary drug of choice among injectors was heroin. Results SEP coverage varies greatly across MSAs, with an average of 3 syringes distributed per 100 injection events (std dev = 0.045; range: 2 syringes per 10 injection events, to 3 syringes per 10,000 injection events). In bivariate regression analyses, a 1 unit difference in the proportion of the population that was MSM per 1,000 was associated with a difference of 0.002 in SEP coverage (p=0.052); early SEP presence was associated with a difference of 0.038 in coverage (p=0.012); and having government funding was associated with a 0.040 difference in SEP coverage (p=0.021). Conclusions This analysis suggests that longer duration of SEP presence may increase syringe distribution and enhance successful programme utilization. Furthermore, MSAs with greater proportions of MSM tend to have better SEP coverage, perhaps providing further evidence that grassroots activism plays an important role in programme implementation and successful SEP coverage. This research provides evidence that government funding for SEPs contributes to better syringe coverage. PMID:18295468

  4. A technical study of TLD beta calibration factor for exposures to depleted uranium

    SciTech Connect

    Ashley, J.C.; Turner, J.E.; McMahan, K.L. [Oak Ridge National Lab., TN (United States); Souleyrette, M.L.; Bogard, R.S. [Oak Ridge Y-12 Plant, TN (United States)

    1995-06-01

    The beta calibration factor for converting light output (on reading a thermoluminescent dosimeter) to shallow dose equivalent has been reexamined through theoretical calculations and experimental measurements. The results support the previously determined value for contact with a depleted uranium slab but indicate that for many actual workplace situations, the contact value may be overly conservative.

  5. Could low dead-space syringes really reduce HIV transmission to low levels?

    PubMed

    Vickerman, P; Martin, N K; Hickman, M

    2013-01-01

    Studies published by Zule and colleagues have suggested that use of low dead-space syringes (LDSS) instead of high dead-space syringes (HDSS) by injecting drug users (IDUs) could dramatically reduce HIV transmission. However, evidence is limited because experiments have considered a small range of syringe types and have been unable to reliably estimate the efficacy of using LDSS for reducing HIV transmission. We critically appraise available evidence to determine whether using LDSS is likely to dramatically reduce HIV transmission. We systematically review the literature on the dead-space volume of syringes and estimate the factor difference in blood volume transferred from sharing LDSS or HDSS. Existing data on the relationship between host viral load and HIV transmission risk is used to evaluate the likely efficacy of using LDSS instead of HDSS. An HIV transmission model is used to make conservative impact projections for switching to using LDSS, and explore the implications of heterogeneity in IDU transmission risk and syringe preferences. Although highly variable, reviewed studies suggest that HDSS have on average 10 times the dead-space volume of LDSS and could result in 6/54/489 times more blood being transferred after 0/1/2 water rinses. Assuming a conservative 2-fold increase in HIV transmission risk per 10-fold increase in infected blood inoculum, HDSS use could be associated with a mean 1.7/3.6/6.5-fold increase in transmission risk compared to LDSS for 0/1/2 rinses. However, even for a low efficacy estimate, modelling suggests that partially transferring to LDSS use from using HDSS could dramatically reduce HIV prevalence (generally >33% if LDSS use is 50%), but impact will depend on IDU behavioural heterogeneity and syringe preference. Indirect evidence suggests that encouraging HDSS users to use LDSS could be a powerful HIV prevention strategy. There is an urgent need to evaluate the real life effectiveness of this strategy. PMID:23206493

  6. Wrap spring clutch syringe ram and frit mixer

    DOEpatents

    Simpson, Frank B.

    2006-07-25

    A wrap spring clutch syringe ram pushes at least one syringe with virtually instantaneous starting and stopping, and with constant motion at a defined velocity during the intervening push. The wrap spring clutch syringe ram includes an electric motor, a computer, a flywheel, a wrap spring clutch, a precision lead screw, a slide platform, and syringe reservoirs, a mixing chamber, and a reaction incubation tube. The electric motor drives a flywheel and the wrap spring clutch couples the precision lead screw to the flywheel when a computer enables a solenoid of the wrap spring clutch. The precision lead screw drives a precision slide which causes syringes to supply a portion of solution into the mixing chamber and the incubation tube. The wrap spring clutch syringe ram is designed to enable the quantitative study of solution phase chemical and biochemical reactions, particularly those reactions that occur on the subsecond time scale.

  7. Syringe Disposal among Injection Drug Users in Harlem and the Bronx during the New York State Expanded Syringe Access Demonstration Program

    ERIC Educational Resources Information Center

    Cleland, Charles M.; Deren, Sherry; Fuller, Crystal M.; Blaney, Shannon; McMahon, James M.; Tortu, Stephanie; Des Jarlais, Don C.; Vlahov, David

    2007-01-01

    Effective January 1, 2001, New York State enacted the Expanded Syringe Access Demonstration Program (ESAP), allowing syringes to be sold in pharmacies without a prescription or dispensed through doctors, hospitals, and clinics to adults. A concern in the assessment of ESAP is its effects on syringe disposal practices. Syringe use data regarding…

  8. Magnet/Syringe Separation Issues V.B. Graves

    E-print Network

    McDonald, Kirk

    of rigid pipe makes it impractical to ship and transport assembled system (syri to the syringe pump procurement. Fig. 1. Existing Design #12;2 Fig 2. Separated System Conceptual Layout to be tilted and may sit directly on the floor (or a mobile baseplate). · The syringe system no longer has

  9. 41 CFR 109-27.5009 - Control of hypodermic needles and syringes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...false Control of hypodermic needles and syringes. 109-27.5009 Section...5009 Control of hypodermic needles and syringes. Effective procedures...physical security of hypodermic needles and syringes to prevent illegal use....

  10. 41 CFR 109-27.5009 - Control of hypodermic needles and syringes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...false Control of hypodermic needles and syringes. 109-27.5009 Section...5009 Control of hypodermic needles and syringes. Effective procedures...physical security of hypodermic needles and syringes to prevent illegal use....

  11. Calibration of the Multi-Factor HJM Model for Energy Market

    NASA Astrophysics Data System (ADS)

    Broszkiewicz-Suwaj, E.; Weron, A.

    2006-05-01

    The purpose of this paper is to show that using the toolkit of interest rate theory, already well known in financial engineering as the HJM model [D. Heath, R. Jarrow, A. Morton, {ITALIC Econometrica} 60, 77 (1992)], it is possible to derive explicite option pricing formula and calibrate the theoretical model to the empirical electricity market. The analysis is illustrated by numerical cases from the European Energy Exchange (EEX) in Leipzig. The multi-factor {ITALIC versus} one-factor HJM models are compared.

  12. Characterization of responses and comparison of calibration factor for commercial MOSFET detectors

    SciTech Connect

    Bharanidharan, Ganesan [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India); Manigandan, Durai [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India); Devan, Krishnamurthy [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India); Subramani, Vellaiyan [Department of Radiotherapy, Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi (India); Gopishankar, Natanasabapathi [Department of Neurosurgery, Gamma Knife Centre, CNC All India Institute of Medical Sciences, New Delhi (India); Ganesh, Tharmar [Department of Radiotherapy, Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi (India); Joshi, Rakeshchander [Department of Radiotherapy, Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi (India); Rath, Gourakishore [Department of Radiotherapy, Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi (India); Velmurugan, Jagadeesan [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India); Aruna, Prakasarao [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India); Ganesan, Singaravelu [Division of Medical Physics and Lasers, Department of Physics, Anna University, Chennai (India)]. E-mail: sganesan@annauniv.edu

    2005-01-01

    A commercial metal oxide silicon field effect transistor (MOSFET) dosimeter of model TN502-RD has been characterized for its linearity, reproducibility, field size dependency, dose rate dependency, and angular dependency for Cobalt-60 ({sup 6}Co), 6-MV, and 15-MV beam energies. The performance of the MOSFET clearly shows that it is highly reproducible, independent of field size and dose rate. Furthermore, MOSFET has a very high degree of linearity, with r-value > 0.9 for all 3 energies. The calibration factor for 2 similar MOSFET detectors of model TN502-RD were also estimated and compared for all 3 energies. The calibration factor between the 2 similar MOSFET detectors shows a variation of about 1.8% for {sup 6}Co and 15 MV, and for 6 MV it shows variation of about 2.5%, indicating that calibration should be done whenever a new MOSFET is used. However, the detector shows considerable angular dependency of about 8.8% variation. This may be due to the variation in radiation sensitivity between flat and bubble sides of the MOSFET, and indicates that positional care must be taken while using MOSFET for stereotactic radiosurgery and stereotactic radiotherapy dosimetric applications.

  13. Calibrator for microflow delivery systems

    NASA Astrophysics Data System (ADS)

    Marinozzi, Franco; Bini, Fabiano; Cappa, Paolo

    2005-01-01

    An apparatus for calibrating the fluid flow rate down to 3×10-2ml/h is proposed, based on the volumetric pump working principle. Constant flow rate is assured by means of the constant speed at which the plunger of a laboratory syringe is moved. To test effectiveness of the system, a flow sensor, composed by a differential pressure transducer and a needle was calibrated and afterward utilized for characterizing a clinical drug infusion device. The proposed apparatus showed a full scale (FS) uncertainty approximately equal to 3.5% over a range of 6 ml/h. The calibration range starts at 3×10-2ml/h with a 1 ml syringe and at 3×10-3ml/h with a 0.1 ml syringe. The minimum detectable signal (evaluated at 6 dB SNR) was equal to about 1.4×10-2ml/h by using a syringe of 1 ml. The outcomes of the adopted procedure allowed a characterization of the performance of an infusion pump, without the need of the usual but somewhat cumbersome gravimetric calibration standard. Moreover, some issues about the expected resolution and uncertainty, depending on the characteristics of the system, is also reported.

  14. Needle and syringe sharing among Iranian drug injectors

    PubMed Central

    Rafiey, Hassan; Narenjiha, Hooman; Shirinbayan, Peymaneh; Noori, Roya; Javadipour, Morteza; Roshanpajouh, Mohsen; Samiei, Mercedeh; Assari, Shervin

    2009-01-01

    Objective The role of needle and syringe sharing behavior of injection drug users (IDUs) in spreading of blood-borne infections – specially HIV/AIDS – is well known. However, very little is known in this regard from Iran. The aim of our study was to determine the prevalence and associates of needle and syringe sharing among Iranian IDUs. Methods In a secondary analysis of a sample of drug dependents who were sampled from medical centers, prisons and streets of the capitals of 29 provinces in the Iran in 2007, 2091 male IDUs entered. Socio-demographic data, drug use data and high risk behaviors entered to a logistic regression to determine independent predictors of lifetime needle and syringe sharing. Results 749(35.8%) reported lifetime experience of needle and syringe sharing. The likelihood of lifetime needle and syringe sharing was increased by female gender, being jobless, having illegal income, drug use by family members, pleasure/enjoyment as causes of first injection, first injection in roofless and roofed public places, usual injection at groin, usual injection at scrotum, lifetime experience of nonfatal overdose, and history of arrest in past year and was decreased by being alone at most injections. Conclusion However this data has been extracted from cross-sectional design and we can not conclude causation, some of the introduced variables with association with needle and syringe sharing may be used in HIV prevention programs which target reducing syringe sharing among IDUs. PMID:19643014

  15. Storage stability of bevacizumab in polycarbonate and polypropylene syringes.

    PubMed

    Khalili, H; Sharma, G; Froome, A; Khaw, P T; Brocchini, S

    2015-06-01

    PurposeTo compare and examine the storage stability of compounded bevacizumab in polycarbonate (PC) and polypropylene (PP) syringes over a 6-month period. PC syringes have been used in a recent clinical study and bevacizumab stability has not been reported for this type of syringe.MethodsRepackaged bevacizumab was obtained from Moorfields Pharmaceuticals in PC and PP syringes. Bevacizumab from the stored syringes was analysed at monthly time points for a 6-month period and compared with bevacizumab from a freshly opened vial at each time point. SDS-PAGE electrophoresis and size-exclusion chromatography (SEC) was used to observe aggregation and degradation. Dynamic light scattering (DLS) provided information about the hydrodynamic size and particle size distribution of bevacizumab in solution. VEGF binding and the active concentration of bevacizumab was determined by surface plasmon resonance (SPR) using Biacore.ResultsSDS-PAGE and SEC analysis did not show any changes in the presence of higher molecular weight species (HMWS) or degradation products in PC and PP syringes from T0 to T6 compared with bevacizumab sampled from a freshly opened vial. The hydrodynamic diameter of bevacizumab in the PC syringe after 6 months of storage was not significantly different to bevacizumab taken from a freshly opened vial. Using SPR, the VEGF binding activity of bevacizumab in the PC syringe was comparable to bevacizumab taken from a freshly opened vial.ConclusionNo significant difference over a 6-month period was observed in the quality of bevacizumab repackaged into prefilled polycarbonate and polypropylene syringes when compared with bevacizumab that is supplied from the vial. PMID:25853399

  16. Note: calibration of atomic force microscope cantilevers using only their resonant frequency and quality factor.

    PubMed

    Sader, John E; Friend, James R

    2014-11-01

    A simplified method for calibrating atomic force microscope cantilevers was recently proposed by Sader et al. [Rev. Sci. Instrum. 83, 103705 (2012); Sec. III D] that relies solely on the resonant frequency and quality factor of the cantilever in fluid (typically air). This method eliminates the need to measure the hydrodynamic function of the cantilever, which can be time consuming given the wide range of cantilevers now available. Using laser Doppler vibrometry, we rigorously assess the accuracy of this method for a series of commercially available cantilevers and explore its performance under non-ideal conditions. This shows that the simplified method is highly accurate and can be easily implemented to perform fast, robust, and non-invasive spring constant calibration. PMID:25430150

  17. Monte Carlo modeling provides accurate calibration factors for radionuclide activity meters.

    PubMed

    Zagni, F; Cicoria, G; Lucconi, G; Infantino, A; Lodi, F; Marengo, M

    2014-12-01

    Accurate determination of calibration factors for radionuclide activity meters is crucial for quantitative studies and in the optimization step of radiation protection, as these detectors are widespread in radiopharmacy and nuclear medicine facilities. In this work we developed the Monte Carlo model of a widely used activity meter, using the Geant4 simulation toolkit. More precisely the "PENELOPE" EM physics models were employed. The model was validated by means of several certified sources, traceable to primary activity standards, and other sources locally standardized with spectrometry measurements, plus other experimental tests. Great care was taken in order to accurately reproduce the geometrical details of the gas chamber and the activity sources, each of which is different in shape and enclosed in a unique container. Both relative calibration factors and ionization current obtained with simulations were compared against experimental measurements; further tests were carried out, such as the comparison of the relative response of the chamber for a source placed at different positions. The results showed a satisfactory level of accuracy in the energy range of interest, with the discrepancies lower than 4% for all the tested parameters. This shows that an accurate Monte Carlo modeling of this type of detector is feasible using the low-energy physics models embedded in Geant4. The obtained Monte Carlo model establishes a powerful tool for first instance determination of new calibration factors for non-standard radionuclides, for custom containers, when a reference source is not available. Moreover, the model provides an experimental setup for further research and optimization with regards to materials and geometrical details of the measuring setup, such as the ionization chamber itself or the containers configuration. PMID:25195174

  18. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...syringe and a high-pressure injector which are used to inject contrast material into the heart, great vessels, and coronary arteries to study the heart and vessels by x-ray photography. (b) Classification. Class II (performance...

  19. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...syringe and a high-pressure injector which are used to inject contrast material into the heart, great vessels, and coronary arteries to study the heart and vessels by x-ray photography. (b) Classification. Class II (performance...

  20. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...syringe and a high-pressure injector which are used to inject contrast material into the heart, great vessels, and coronary arteries to study the heart and vessels by x-ray photography. (b) Classification. Class II (performance...

  1. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...syringe and a high-pressure injector which are used to inject contrast material into the heart, great vessels, and coronary arteries to study the heart and vessels by x-ray photography. (b) Classification. Class II (performance...

  2. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...syringe and a high-pressure injector which are used to inject contrast material into the heart, great vessels, and coronary arteries to study the heart and vessels by x-ray photography. (b) Classification. Class II (performance...

  3. Developing biotechnology company's future positioning strategy in prefilled syringe market

    E-print Network

    Lee, Joonhaeng, S.M. Massachusetts Institute of Technology

    2010-01-01

    The primary goal for the thesis is to develop a recommendation for Amgen's future prefilled syringe strategy related to its drug process development, supplier relationship management plan, supply and sourcing, and procurement. ...

  4. A national physician survey on prescribing syringes as an HIV prevention measure

    Microsoft Academic Search

    GE Macalino; D Dhawan Sachdev; JD Rich; C Becker; LJ Tan; L Beletsky; S Burris

    2009-01-01

    BACKGROUND: Access to sterile syringes is a proven means of reducing the transmission of human immunodeficiency virus (HIV), viral hepatitis, and bacterial infections among injection drug users. In many U.S. states and territories, drug paraphernalia and syringe prescription laws are barriers to syringe access for injection drug users (IDUs): pharmacists may be reluctant to sell syringes to suspected IDUs, and

  5. Oven melting encapsulization of hypodermic needles by syringes.

    PubMed

    Fortner, T; Wynn, H; Heffner, H; Colton, J

    2009-01-01

    The results of a study to determine the time and temperature conditions necessary to melt standard injection syringes are presented. The polypropylene syringes are melted to form a solid block of material encapsulating the attached stainless steel hypodermic needles, making them appropriate for further processing into other products. The desired result was obtained after two hours at 200 degrees C and can be replicated easily in a location such as a rural clinic in a developing nation. PMID:19848854

  6. [The Baxter AS 50 syringe pump: a comparison with propofol-specific syringe pumps].

    PubMed

    Terai, T; Tanaka, M; Suzuki, N

    2001-01-01

    We used a Baxter AS 50 syringe pump for intravenous anesthesia with propofol, and compared it with a Grasby 3500 and a Terumo STC-525 X pumps, which are specifically designed for propofol infusion. The AS 50 pump is a programmable syringe infusion pump, which allows us to register up to 70 drug names in 10 categories and various infusion modes for drugs. There are 14 types of continuous infusion mode, a custom dilution mode, and three types of time infusion modes. The continuous infusion mode in mg.kg-1.h-1 is available for propofol anesthesia. Operation of this pump is simple and user-friendly, as with for the other propofol-specific pumps. Although the AS 50 pump is limited to a maximum bolus rate of 438 ml.h-1, this restriction is not a serious problem in clinical practice. The AS 50 pump is also equipped with an RS-232 C digital interface port to allow external remote monitoring or automated control. On-line simulation of blood propofol concentration is possible with a simulation program such as Propofol-Mon. Our impression is that the AS 50 pump is compact, easy to use, accurate and reliable for propofol anesthesia. PMID:11211760

  7. Comparing HIV-related syringe-sharing behaviors among female IDU engaging versus not engaging in commercial sex

    Microsoft Academic Search

    Joseph T. F. Lau; Hi Yi Tsui; Yun Zhang; Feng Cheng; Linglin Zhang; Jianxin Zhang; Ning Wang

    2008-01-01

    BackgroundTo compare the prevalence of syringe-sharing behaviors and other HIV-related characteristics among female injecting drug users (IDU) engaging and not engaging in sex work and to identify factors associated with such risk behaviors in the two groups.

  8. A source of E and H fields for antenna-factor calibration

    NASA Astrophysics Data System (ADS)

    Fitzgerrell, R. G.

    1984-05-01

    The loop cell used for calibration is fabricated using two intersecting metal sheets joined at the intersection and forming a 36-deg angle. A section of a loop is mounted between two coaxial panel jacks, one on each sheet located at a distance equal to the loop radius from the intersection. A known current through this section of electrically small loop produces calculable E and H fields between the sheets in the plane of the loop. These known fields may be used to determine the antenna factor of small E and H antennas placed in the field if the mutual impedance due to the antenna images in the sheets is negligible and the antenna is not close to the open edges of the cell. Measured and calculated antenna factors agree within + or - 2 dB between 0.25 and 1000 MHz.

  9. [Measuring the calibration factor of a light scattering dust monitor for CO2 arc welding fumes].

    PubMed

    Ojima, Jun

    2002-12-01

    In Japan, a light scattering type digital dust monitor is most commonly used for dust concentration measurement in a working environment. In this study, the calibration factors of a digital dust monitor (K-factor) for several welding fumes were measured in a laboratory. During the experiment, fumes were generated from CO2 arc welding performed by an automatic welding robot. The examined welding wires were JIS Z 3312, Z 3313, Z 3315, Z 3317 and Z 3320. The mass and relative concentrations of the welding fumes were measured simultaneously by a total/respirable (TR) dust sampler and a digital dust monitor at a welding current of 100 A, 150 A, 200 A, 250 A and 300 A. The particle size distributions of welding fumes were measured by a low pressure impactor at a welding current of 100 A and 300 A. A significant effect of the welding current on the K-factor was recognized for all the examined wires. In the most remarkable case, a four-fold difference in the K-factors was found when the fumes were generated from a flux cored wire for mild steel (JIS Z 3313). The particle size distributions of fumes were also affected by the welding current. The coefficients of variation in the measured K-factor were 7.8-40.5%. PMID:12506861

  10. Detector Calibration factor for interstitial in-vivo light dosimetry using isotropic detectors with scattering tip

    PubMed Central

    Zhu, Timothy C; Dimofte, Andreea; Finlay, Jarod C.; Glatstein, Eli; Hahn, Stephen M.

    2015-01-01

    Isotropic detectors with spherical scattering tips are commonly used for in-vivo dosimetry of light fluence rate during photodynamic therapy (PDT). These detectors are typically calibrated in-air. It has been well established that the response of an isotropic detector is a function of the refractive index (n) of the surrounding medium when it is surrounded by an infinite medium of uniform n. However, there are few, if any, studies of the isotropic detector response when the detector is placed in a secondary medium, such as air, before it is placed inside the infinite uniform medium. This condition often arises when one places the isotropic detector inside an air-filled catheter which is then inserted into a turbid medium, such as tissue. We have performed theoretical and experimental studies to determine the correction factors in water (n = 1.33), which has a refractive index similar to that of tissue (n = 1.4). We found that the resulting correction factor is almost the same (within 20%) as the correction factor for the outermost medium (the water) rather than the immediate medium surrounding the isotropic detector (air). The detector correction factor is also a function of the index of refraction of the probe material. For a 1-mm diameter probe from CardioFocus, the detector correction factor varied from 1 (in air) to 1.09 (at air-water interface) to 1.49 (completely submerged in water). At the air-water interface the spherical bulb of the isotropic detector is placed half in air and half in water. For a 0.5-mm diameter probe from the same company, it varied from 1 (in air) to 1.32 (at air-water interface) to 1.87 (in water). For a 0.3-mm diameter probe from the same company, it varied from 1 (in air) to 1.32 (at air-water interface) to 1.71 (in water). We have also found that the detector response changes by less than 10% when the detector position is varied from touching the catheter wall closest to the light source, to not touching, to touching the catheter wall farthest from the light source. The calibration factors between individual isotropic detectors of the same type varied within 5% for all detector types. Thus mean correction factor can be used for each individual isotropic detector of the same type.

  11. Examination of energy spectrum acquisition method using shielded radiopharmaceutical syringes.

    PubMed

    Uto, Tomoyuki

    2009-09-20

    I previously reported on a spectrum sampling method with shielded syringes before use, although the report included only data obtained using technetium-99m. In this study, we sampled the energy spectrum in a similar manner using thallium-201, iodine-123, and gallium-67. In spectrum sampling, a radioisotopic source in a cylindrical shield is located midway between two opposed gamma-camera detectors equipped with collimators. An unshielded syringe before use emits excessive radiation and makes count rates too high to obtain accurate photopeak values. With a shielded syringe, we can sample the spectrum of radiation leaked from the needle side of the syringe and the unshielded part of its plunger side. Consequently, the detectors are exposed to lower-dose gamma rays and probably offer count rates appropriate to measure accurate photopeak values. The study results show the general validity of spectrum sampling and photopeak acquisition in our method. However, a syringe should be located accurately perpendicular to each detector; otherwise, gamma rays did not reach the detectors in some cases, resulting in measurement failures. In addition, when low-energy collimators are used for sampling from (123)I sources, photopeak values depend on penetration. More accurate measurements require the use of high-energy collimators. PMID:19828931

  12. Supermarket tampering: cocaine detected in syringes and in fruit.

    PubMed

    Tomlinson, J A; Crowe, J B; Ranieri, N; Kindig, J P; Platek, S F

    2001-01-01

    Product tampering, as detailed by the Federal Anti-Tampering Act of 1983 (1), is a felony punishable by both fine and imprisonment. The rationale for product tampering ranges from pranks and attention seeking acts to extortion, terrorism, and homicide. One such case submitted for analysis involved four medical syringes found in a supermarket and suspected of being used to tamper with various products. One of the syringes was found piercing a pear while the other three syringes were found with needles exposed in other parts of the supermarket. Microscopic analysis was used to collect residue from the syringe barrels and the pear. A multidiscipline approach involving SLM, PLM, including microchemical analysis, FTIR, and GC/MS analyses, performed on the residual liquid found in the syringe barrels and in the suspect pear, confirmed the presence of cocaine. This multidisciplinary approach is often necessary when there is a possible health risk to the public and rapid response is important. With this approach, it was quickly determined which drugs or poisons were used in this tampering. PMID:11210900

  13. Volumetric Lattice Boltzmann Simulation for Fluid dynamics and Turbulence in Practical Syringes

    NASA Astrophysics Data System (ADS)

    Lima, Everton; Deep, Debanjan; Yu, Huidan (Whitney)

    2012-11-01

    We conduct numerical experiments to study fluid dynamics and turbulence in syringes using volumetric lattice Boltzmann method (VLBM) that is developed for dealing with arbitrary moving boundaries. Several common used medical syringes are used to predict the efficiency and safety of syringes experiencing low flow infusion rates. It is found that smaller size syringes reach a steady flow rate much sooner than larger ones, which are in quantitative agreement with experimental results. The relation between the syringe size and its steady flow rate is revealed. At low flow rates, corner vortices are observed. We explore conditions that lead to turbulent flow aiming to aid safer syringe application in nursing practices.

  14. Needle and Syringe Cleaning Practices among Injection Drug Users.

    ERIC Educational Resources Information Center

    Fisher, Dennis G.; Harbke, Colin R.; Canty, John R.; Reynolds, Grace L.

    2002-01-01

    Evaluates the effect of needle exchange on the bleach-mediated disinfection (BMD) practices of 176 needle and syringe sharing injection drug users (IDUs). Results reveal that IDUs who traded sex for money or drugs were less likely to practice BMD, and IDUs who reported a reduced number of sex partners were more likely to practice BMD. (Contains 36…

  15. Micron-scale droplet deposition from a retreating syringe

    NASA Astrophysics Data System (ADS)

    Qian, Bian; Loureiro, Melissa; Tripathi, Anubhav; Breuer, Kenneth

    2008-11-01

    Contact drop dispensing is initiated by the formation of a liquid bridge between the substrate and a dispensing syringe. As the syringe retreats, the liquid bridge stretches grows and breaks, leaving a drop on the substrate. The dynamics of liquid bridge breaking have broad interests in crystal growth, inkjet printing and micromanipulation, and contact drop dispensing has many applications in manufacturing and process control. The dynamics of the drop formation are surprisingly complex and the resulting droplet size can vary by orders of magnitude depending on the syringe diameter, d, fluid properties and syringe retraction speed, u. Experiments show that at low retraction speeds, arbitrarily large drops can be formed, their size scaling with u-1/2. At a critical speed, the contact line on the substrate reverses direction and shrinks rather than expands as the needle retreats. Above this speed, droplets as small as 50 microns can be formed - much smaller than the characteristic needle dimension (d 500?m). The limiting droplet size appears to be determined by dynamics of the contact line. We present experimental results and scaling based on measurements over a wide range of physical and geometric parameters.

  16. Effect of environmental conditions on radon concentration-track density calibration factor of solid-state nuclear track detectors

    NASA Astrophysics Data System (ADS)

    El-Sersy, A.; Mansy, M.; Hussein, A.

    2004-04-01

    In this work, the effect of environmental conditions viz., temperature (T) and relative humidity (RH) on the track density--radon concentrations calibration factor (K) has been studied for CR-39 and LR-115 track detectors. The factor K was determined using a reference radon chamber in the National Institute for Standards (NIS) in Egypt. Track detectors were etched at the recommended optimum etching conditions. It is found that, the calibration factor K varies with both T and RH, so they should be considered for the sake of uncertainty reduction. Good agreement is found between the calculated and measured values of K and the compatibility between them is in the range of experimental uncertainty.

  17. Disinfection of Syringes Contaminated With Hepatitis C Virus by Rinsing With Household Products

    PubMed Central

    Binka, Mawuena; Paintsil, Elijah; Patel, Amisha; Lindenbach, Brett D.; Heimer, Robert

    2015-01-01

    Background.?Hepatitis C virus (HCV) transmission among people who inject drugs (PWID) is associated with the sharing of injection paraphernalia. People who inject drugs often “disinfect” used syringes with household products when new syringes are unavailable. We assessed the effectiveness of these products in disinfecting HCV-contaminated syringes. Methods.?A genotype-2a reporter virus assay was used to assess HCV infectivity in syringes postrinsing. Hepatitis C virus-contaminated 1 mL insulin syringes with fixed needles and 1 mL tuberculin syringes with detachable needles were rinsed with water, Clorox bleach, hydrogen peroxide, ethanol, isopropanol, Lysol, or Dawn Ultra at different concentrations. Syringes were either immediately tested for viable virus or stored at 4°C, 22°C, and 37°C for up to 21 days before viral infectivity was determined. Results.?Most products tested reduced HCV infectivity to undetectable levels in insulin syringes. Bleach eliminated HCV infectivity in both syringes. Other disinfectants produced virus recovery ranging from high (5% ethanol, 77% ± 12% HCV-positive syringes) to low (1:800 Dawn Ultra, 7% ± 7% positive syringes) in tuberculin syringes. Conclusions.?Household disinfectants tested were more effective in fixed-needle syringes (low residual volume) than in syringes with detachable needles (high residual volume). Bleach was the most effective disinfectant after 1 rinse, whereas other diluted household products required multiple rinses to eliminate HCV. Rinsing with water, 5% ethanol (as in beer), and 20% ethanol (as in fortified wine) was ineffective and should be avoided. Our data suggest that rinsing of syringes with household disinfectants may be an effective tool in preventing HCV transmission in PWID when done properly. PMID:26034767

  18. A piezoelectric vibration-based syringe for reducing insertion force

    NASA Astrophysics Data System (ADS)

    Huang, Y. C.; Tsai, M. C.; Lin, C. H.

    2012-12-01

    Puncturing of the human skin with a needle is perhaps the most common invasive medical procedure. Clinical studies have revealed that tissue deformation and needle deflection are the primary problem for needle misplacement in percutaneous procedures. To avoid this, various techniques for reducing insertion forces during needle insertion have been considered. This paper presents a piezoelectric vibration-based syringe to reduce insertion force. AC power was applied to the piezoelectric elements to vibrate the needle with high frequency and thereby reduce the friction and cutting forces between the needle and tissue. Vibration mode shapes of the needle were observed by finite element analysis and verified by experimental results. Effects of reducing insertion force via the vibrating needle were also confirmed by inserting the needle into the porcine tissues. The proposed syringe, which minimizes the insertion force and overcomes limitations of needle materials, can be widely utilized in robot-assisted needle insertion systems.

  19. Stability of ondansetron hydrochloride and 12 medications in plastic syringes.

    PubMed

    Stewart, J T; Warren, F W; King, D T; Venkateshwaran, T G; Fox, J L

    1998-12-15

    The stability and compatibility of ondansetron hydrochloride with neostigmine methylsulfate, naloxone hydrochloride, midazolam hydrochloride, fentanyl citrate, alfentanil hydrochloride, atropine sulfate, morphine sulfate, meperidine hydrochloride, propofol, droperidol, metoclopramide monohydrochloride, and glycopyrrolate were studied. Ondansetron 1.33 or 1.0 mg/mL was combined with 0.9% sodium chloride injection and each of the 12 drugs in duplicate in plastic syringes (or glass for propofol). The syringes were stored at 21.8-23.4 or 4 degrees C in the dark, except for those containing propofol, which were stored at ambient temperature. Samples were removed at 0, 4, 8, and 24 hours for analysis by high-performance liquid chromatography and pH measurement; the propofol-containing samples were removed at 0, 1, 2, and 4 hours. Syringes were visually assessed for color and clarity, and particulate content was measured with a particle counter at the end of the study period. All solutions containing ondansetron retained more than 90% of their initial ondansetron concentration. Solutions containing each of the other drugs except droperidol retained more than 90% of their initial concentration of these drugs. The solutions containing droperidol retained more than 90% of their initial droperidol concentration for up to eight hours at ambient temperature but precipitated quickly at 4 degrees C. In combinations of ondansetron 1.33 or 1.0 mg/mL and 10 of 12 drugs, all drugs were stable for 24 hours in plastic syringes at 23 and 4 degrees C; ondansetron hydrochloride 1.0 mg/mL and propofol 1.0 and 5.0 mg/mL in admixtures were stable for 4 hours, and droperidol on its own and combined with ondansetron 1.0 mg/mL was stable for no more than 8 hours at ambient temperature. PMID:9872702

  20. Investigation of factors affecting the heater wire method of calibrating fine wire thermocouples

    NASA Technical Reports Server (NTRS)

    Keshock, E. G.

    1972-01-01

    An analytical investigation was made of a transient method of calibrating fine wire thermocouples. The system consisted of a 10 mil diameter standard thermocouple (Pt, Pt-13% Rh) and an 0.8 mil diameter chromel-alumel thermocouple attached to a 20 mil diameter electrically heated platinum wire. The calibration procedure consisted of electrically heating the wire to approximately 2500 F within about a seven-second period in an environment approximating atmospheric conditions at 120,000 feet. Rapid periodic readout of the standard and fine wire thermocouple signals permitted a comparison of the two temperature indications. An analysis was performed which indicated that the temperature distortion at the heater wire produced by the thermocouple junctions appears to be of negligible magnitude. Consequently, the calibration technique appears to be basically sound, although several practical changes which appear desirable are presented and discussed. Additional investigation is warranted to evaluate radiation effects and transient response characteristics.

  1. Experimental determination of mode correction factors for thermal method spring constant calibration of AFM cantilevers using laser Doppler vibrometry.

    PubMed

    Gates, Richard S; Osborn, William A; Pratt, Jon R

    2013-06-28

    Mode correction factors (MCFs) represent a significant adjustment to the spring constant values measured using the thermal cantilever calibration method. Usually, the ideal factor of 0.971 for a tipless rectangular cantilever is used, which adjusts the value by 3% for the first flexural mode. An experimental method for determining MCFs has been developed that relies on measuring the areas under the first few resonance peaks for the flexural mode type. Using this method, it has been shown that MCFs for the first flexural mode of commercially available atomic force microscope cantilevers actually vary from 0.95 to 1.0, depending on the shape and end mass of the cantilever. Triangular shaped cantilevers tend to lower MCFs with tipless versions providing the lowest values. Added masses (including tips) tend to increase the first flexural mode's MCF to higher values with large colloid probes at the high extreme. Using this understanding and applying it to the recently developed laser Doppler vibrometry thermal calibration method it is now possible to achieve very accurate and precise cantilever spring constant calibrations (uncertainties close to ±1%) with commonly available commercial cantilevers such as tipped rectangular and triangular cantilevers, and colloid probes. PMID:23723188

  2. User preference for a portable syringe pump for iloprost infusion

    PubMed Central

    Laria, Antonella; Lurati, Alfredo Maria; Re, Katia Angela; Marrazza, Maria Grazia; Mazzocchi, Daniela; Farina, Alberto; Scarpellini, Magda

    2015-01-01

    Purpose Administration of intravenous iloprost – a first-line European League Against Rheumatism (EULAR)-recommended choice for the treatment of scleroderma (SSc)-related digital vasculopathy – requires repeated treatment cycles of 6 hours per day in a hospital setting. During the infusion, patient mobility is considerably restricted due to the size and fixity of traditional syringe pumps. The aim of this study was to evaluate the satisfaction level of patients and nurses, after the introduction of a new portable syringe pump (Infonde®, Italfarmaco S.p.A., Milan, Italy) at the Department of Rheumatology, Magenta Hospital, Milan, Italy. Patients and methods Thirty-four consecutive SSc patients receiving stable therapy with iloprost, previously administered with a fixed pump, were treated using the portable Infonde® pump. Patients (n=34) and nurses (n=4) were asked to answer a nine- and six-item questionnaire, respectively, to assess the satisfaction of the administration comparing the new device versus the previous one. The health care staff of the ward developed the questionnaire, and the response scores ranged from 0 (fixed device better) to 10 (portable device better); thus a score >5 indicates a preference for Infonde®. Results Patients’ answers indicated a preference towards the new portable syringe pump, versus the previous fixed pump. Questionnaires administered to patients generated a total of 306 responses, with over 95% of the responses in the range 8–10, of which 89% had a score equal to 10. The responses of nurses showed a score equal to 10 in 100% cases. No significant adverse events were recorded, indicating no change in the tolerability profile of the drug. Conclusion Iloprost administration with Infonde® pump was preferred by both patients and health care professionals, and was well tolerated. The possibility to perform daily activities and the freedom of movement suggest a positive impact of Infonde® on the treatment, with a potential favorable effect on the quality of life of patients during the many hours spent receiving the infusion.

  3. Effects of syringe material and silicone oil lubrication on the stability of pharmaceutical proteins.

    PubMed

    Krayukhina, Elena; Tsumoto, Kouhei; Uchiyama, Susumu; Fukui, Kiichi

    2015-02-01

    Currently, polymer-based prefillable syringes are being promoted to the pharmaceutical market because they provide an increased break resistance relative to traditionally used glass syringes. Despite this significant advantage, the possibility that barrel material can affect the oligomeric state of the protein drug exists. The present study was designed to compare the effect of different syringe materials and silicone oil lubrication on the protein aggregation. The stability of a recombinant fusion protein, abatacept (Orencia), and a fully human recombinant immunoglobulin G1, adalimumab (Humira), was assessed in silicone oil-free (SOF) and silicone oil-lubricated 1-mL glass syringes and polymer-based syringes in accelerated stress study. Samples were subjected to agitation stress, and soluble aggregate levels were evaluated by size-exclusion chromatography and verified with analytical ultracentrifugation. In accordance with current regulatory expectations, the amounts of subvisible particles resulting from agitation stress were estimated using resonant mass measurement and dynamic flow-imaging analyses. The amount of aggregated protein and particle counts were similar between unlubricated polymer-based and glass syringes. The most significant protein loss was observed for lubricated glass syringes. These results suggest that newly developed SOF polymer-based syringes are capable of providing biopharmaceuticals with enhanced physical stability upon shipping and handling. PMID:25256796

  4. The Washington Needle Depot: fitting healthcare to injection drug users rather than injection drug users to healthcare: moving from a syringe exchange to syringe distribution model

    PubMed Central

    2010-01-01

    Needle exchange programs chase political as well as epidemiological dragons, carrying within them both implicit moral and political goals. In the exchange model of syringe distribution, injection drug users (IDUs) must provide used needles in order to receive new needles. Distribution and retrieval are co-existent in the exchange model. Likewise, limitations on how many needles can be received at a time compel addicts to have multiple points of contact with professionals where the virtues of treatment and detox are impressed upon them. The centre of gravity for syringe distribution programs needs to shift from needle exchange to needle distribution, which provides unlimited access to syringes. This paper provides a case study of the Washington Needle Depot, a program operating under the syringe distribution model, showing that the distribution and retrieval of syringes can be separated with effective results. Further, the experience of IDUs is utilized, through paid employment, to provide a vulnerable population of people with clean syringes to prevent HIV and HCV. PMID:20047690

  5. The Washington Needle Depot: fitting healthcare to injection drug users rather than injection drug users to healthcare: moving from a syringe exchange to syringe distribution model.

    PubMed

    Small, Dan; Glickman, Andrea; Rigter, Galen; Walter, Thia

    2010-01-01

    Needle exchange programs chase political as well as epidemiological dragons, carrying within them both implicit moral and political goals. In the exchange model of syringe distribution, injection drug users (IDUs) must provide used needles in order to receive new needles. Distribution and retrieval are co-existent in the exchange model. Likewise, limitations on how many needles can be received at a time compel addicts to have multiple points of contact with professionals where the virtues of treatment and detox are impressed upon them. The centre of gravity for syringe distribution programs needs to shift from needle exchange to needle distribution, which provides unlimited access to syringes. This paper provides a case study of the Washington Needle Depot, a program operating under the syringe distribution model, showing that the distribution and retrieval of syringes can be separated with effective results. Further, the experience of IDUs is utilized, through paid employment, to provide a vulnerable population of people with clean syringes to prevent HIV and HCV. PMID:20047690

  6. Pharmacy access to syringes among injecting drug users: follow-up findings from Hartford, Connecticut.

    PubMed Central

    Singer, M; Baer, H A; Scott, G; Horowitz, S; Weinstein, B

    1998-01-01

    OBJECTIVE: To break the link between drug use and the human immunodeficiency virus (HIV), in 1992 the state of Connecticut rescinded a 14-year ban on pharmacy sales of syringes without a physician's prescription. In 1993, the Center for Disease Control and Prevention (CDC) evaluated the impact of the new legislation on access to syringes among injecting drug users (IDUs) and found an initial pattern of expanded access. However, it also found that some pharmacies, after negative experiences with IDU customers, reverted to requiring a prescription. This chapter reports findings from a four-year follow-up study of current IDU access to over-the-counter (OTC) pharmacy syringes in Hartford, Connecticut. METHODS: Through structured interviews, brief telephone interviews, and mailed surveys, data on nonprescription syringe sale practices were collected on 27 pharmacies, including 18 of the 21 pharmacies in Hartford and none from pharmacies in contiguous towns, during June and July 1997. Interview data on pharmacy syringe purchase from two sample of IDUs, a group of out-of-treatment injectors recruited through street outreach, and a sample of users of the Hartford Needle Exchange Program, also are reported. RESULTS: The study found that, while market trends as well as negative experiences have further limited pharmacy availability of nonprescription syringes, pharmacies remain an important source of sterile syringes for IDUs. However, the distribution of access in not even; in some areas of the city it is much easier to purchase nonprescription syringes than in other. All of the seven pharmacies located on the north end of Hartford reported that they had a policy of selling OTC syringes, whereas only six (54.5%) of the II pharmacies located on the south end have such a policy. Overt racial discrimination was not found to be a barrier to OTC access to syringes. CONCLUSIONS: To further decrease acquired immunodeficiency syndrome (AIDS) risk among IDUs, there is a need for public education to counter empirically unsupported stereotypes about IDUs that diminish their access to health care and AIDS prevention resources and services. In states or cities where pharmacy sale of nonprescription syringes is illegal, policy makers should examine the benefits of removing existing barriers to sterile syringe acquisition. In cases in which pharmacy sale of nonprescription syringes is legal, local health departments should implement educational programs to inform pharmacy staff and management about the critically important role low-cost (or cost-free), sterile syringe access can play in HIV prevention. PMID:9722813

  7. Building a city wide service for exchanging needles and syringes.

    PubMed Central

    Gruer, L; Cameron, J; Elliott, L

    1993-01-01

    How best can injecting drug misusers obtain clean injecting equipment in a city where drug injecting is widespread? An exchange service for needles and syringes throughout Glasgow has been established in health centres and clinics in the evening. Over the past four years seven new exchanges have been opened and over 2700 injecting drug misusers have attended. Attendances rose from under 1000 in 1988 to 28,000 in 1992. The exchanges also provide a wide range of other health and social services. Public hostility to the exchanges has abated. During the same period equipment sharing in the city diminished and the observed prevalence of HIV among injecting drug misusers stabilised at around 1%. Images FIG 1 FIG 2 FIG 3 PMID:8518609

  8. [Interest of Ineurope syringe for nerve agent intoxication].

    PubMed

    Rousseau, J-M; Besse Bardot, I; Franck, L; Libert, N; Lallement, G; Clair, P

    2009-05-01

    Chemical weapons represent an ever-growing threat, not only for military forces but also for civilian populations. Nerve agents such as those used in terrorist attacks by the Aum sect in Tokyo are among the deadliest of those non conventional weapons. The French military health service has developed a new auto-injector presenting as a self-usable dual-chamber syringe and successfully obtained a new drug approval to provide this new emergency treatment for the military and civilians. After a short review of the pathophysiology and clinical presentation of acute nerve agent, the authors report the development and the process of new drug application. They finally suggest a clinical guideline for practical use in case of terrorist attack. PMID:19349137

  9. A simple pore water hydrogen diffusion syringe sampler

    USGS Publications Warehouse

    Vroblesky, D.A.; Chapelle, F.H.; Bradley, P.M.

    2007-01-01

    Molecular hydrogen (H2) is an important intermediate product and electron donor in microbial metabolism. Concentrations of dissolved H 2 are often diagnostic of the predominant terminal electron-accepting processes in ground water systems or aquatic sediments. H2 concentrations are routinely measured in ground water monitoring wells but are rarely measured in saturated aquatic sediments due to a lack of simple and practical sampling methods. This report describes the design and development (including laboratory and field testing) of a simple, syringe-based H 2 sampler in (1) saturated, riparian sediments, (2) surface water bed sediments, and (3) packed intervals of a fractured bedrock borehole that are inaccessible by standard pumped methods. ?? 2007 National Ground Water Association.

  10. Time frequency analysis of dynamic syringe friction - the benefits of an O-ring plunger seal design

    Microsoft Academic Search

    J. F. Kalafut

    2003-01-01

    Syringe friction is of interest to control and system engineers designing automated pharmaceutical injection systems. The dynamic friction properties of a 4 lobe, O-ring plunger seal syringe design are examined with the Short Time Fourier Transform (STFT). The results are contrasted to the friction properties of a syringe design with a rubber cover plunger seal. Analysis indicates the magnitude of

  11. In-syringe magnetic stirring-assisted dispersive liquid-liquid microextraction for automation and downscaling of methylene blue active substances assay.

    PubMed

    Suárez, Ruth; Horstkotte, Burkhard; Cerdà, Victor

    2014-12-01

    A simple and rapid method for the determination of the methylene blue active substances assay based on in-syringe automation of magnetic stirring-assisted dispersive liquid-liquid microextraction was developed. The proposed method proved to be valid for the determination of anionic surfactant in waste, pond, well, tap, and drinking water samples. Sample mixing with reagents, extraction and phase separation were performed within the syringe of an automated syringe pump containing a magnetic stirring bar for homogenization and solvent dispersion. The syringe module was used upside-down to enable the use of chloroform as an extraction solvent of higher density than water. The calibration was found to be linear up to 0.3mg/L using only 200 µL of solvent and 4 mL of sample. The limits of detection (3?) and quantification (10?) were 7.0 µg/L and 22 µg/L, respectively. The relative standard deviation for 10 replicate determinations of 0.1mg/L SBDS was below 3%. Concentrations of anionic surfactants in natural water samples were in the range of 0.032-0.213 mg/L and no significant differences towards the standard method were found. Standard additions gave analyte recoveries between 95% and 106% proving the general applicability and adequateness of the system to MBSA index determination. Compared to the tedious standard method requiring up to 50 mL of chloroform, the entire procedure took only 345 s using 250-times less solvent. PMID:25159446

  12. [Measurement of peak correction factor of Farmer chamber for calibration of flattening filter free (FFF) clinical photon beams].

    PubMed

    Kontra, Gábor; Major, Tibor; Polgár, Csaba

    2015-06-01

    Farmer-type ionization chambers are considered the most reliable detectors and for this reason they are most frequently used for the calibration of photon beams of medical linear accelerators. Flattening filter free (FFF) photon beams of linear accelerators have recently started to be used in radiotherapy. The dose profile of FFF beams is peaked in the center of the field and the dose distribution will be inhomogeneous along the axis of the 2.3 cm long measuring volume of the Farmer chamber. The peaked radiation field will result in volume averaging effects in the large Farmer chamber, therefore this chamber will underestimate the true central axis dose. Our objective was to determine the value of the peak correction factor (Kp) of Farmer-type chamber with measurements to avoid the underestimation of the central axis dose during the calibration of FFF radiation fields. Measurements were made with 6 MV and 10 MV flattened (6X and 10X) and FFF beams (6XFFF and 10XFFF) of a Varian TrueBeam medical linear accelerator in a solid water phantom at 10 cm depth. The source surface distance (SSD) was 100 cm, the field size was 10×10 cm and the dose rate was always 400 MU/min during the measurements. We delivered 100 MU in each measurement and the absorbed dose to water was calculated according to the IAEA TRS-398 dosimetry protocol. The measured signals of the ionization chambers were always corrected for the ion recombination loss. The ion recombination correction factors (Kr) were determined with the two-voltage method separately for the used ion chambers and for flattened and unflattened beams. First, we measured the dose to water with PTW TM30012 Farmer chamber in 6XFFF and 6X beams, then calculated the ratio of doses of 6XFFF and 6X beams (R6,Farmer). Immediately after this we repeated the above measurements with PTW TM31010 Semiflex chamber and determined the ratio of doses of 6XFFF and 6X beams again (R6,Semiflex). The length of the sensitive volume of the Semiflex chamber is only 6.5 mm. According to our dose profile measurements the peak correction factor of this chamber equals to unity for both photon energies. As a consequence R6,Semiflex is larger than R6,Farmer and Kp6XFFF = R6,Semiflex / R6,Farmer, where Kp6XFFF is the peak correction factor of the Farmer chamber in 6XFFF beam. The advantage of this method is that we have to calculate ratio of doses, so it is not necessary to know the calibration factors of the chambers. Repeating the above measurements with 10X and 10XFFF beams we determined the peak correction factor of Farmer chamber for 10XFFF beam, too (Kp10XFFF). According to our measurements Kp6XFFF = 1.0025 and Kp10XFFF = 1.009. The bigger peak correction factor for 10XFFF beam is in accordance with the fact that the peak of dose profile is steeper for higher photon energy. The above described method for the determination of Kp can be used for other photon energies and other large volume ionization chambers. PMID:26035159

  13. Approval of Syringe Exchange Programs in California: Results From a Local Approach to HIV Prevention

    PubMed Central

    Bluthenthal, Ricky N.; Heinzerling, Keith G.; Anderson, Rachel; Flynn, Neil M.; Kral, Alex H.

    2008-01-01

    Objectives. We studied the effect of local approval of syringe exchange programs in California (through Assembly AB136) on program availability and performance. Methods. We determined the number of active syringe exchange programs in California by conducting Internet searches and obtaining information from the state and from local programs. To track changes in program availability and performance between 2000 and 2002, we interviewed 24 program directors annually for 3 years about program characteristics, syringe exchange policies, law enforcement contact, and other issues. We conducted multivariate analyses to determine whether AB136 approval status was associated with changes in performance. Results. Fifteen local governments (13 counties and 2 cities) enacted the new law by 2002, and operating syringe exchange programs increased from 24 to 35. The proportion of these programs that were not locally approved declined from 54% to 40%. No new approved programs were started in high-need counties. Total syringes exchanged increased by more than 1 million per year, average annual budgets increased by more than 50%, and police harassment of the program volunteers, clients, and operators declined. Improvements at approved syringe exchange programs accounted for these changes. Conclusions. Statewide approval and funding appears necessary to further syringe exchange availability in California. PMID:17538068

  14. Version 3.0 SOP 11 --Calibration of gas loop October 12, 2007 Page 1 of 3

    E-print Network

    Version 3.0 SOP 11 -- Calibration of gas loop October 12, 2007 Page 1 of 3 SOP 11 Gravimetric calibration of the volume of a gas loop using water 1. Scope and field of application This procedure describes the syringe to the loop/valve assembly, · Helium leak detector (e.g., Gow-Mac Instrument Co., Bethlehem, PA, U

  15. The report analyses the total disposable medical device market with focus on syringes. It compares syringes segments, RTF and bulk syringes by value and volume. The report also analyzes major markets such as US, Germany, UK, Italy, and Russia

    Microsoft Academic Search

    Disposable medical device is a very important part of the total medical device industry. For the last few years disposable market is growing continuously and showing a bright growth trend in near future. Needles and syringes are most on-demand product segment of disposable medical device market. Other segments of the market are also showing positive growth trends like disposable gloves,

  16. Plastic-Syringe Induced Silicone Contamination in Organic Photvoltaic Fabrication: Implications for Small-Volume Additives

    SciTech Connect

    Carr, John A.; Nalwa, Kanwar S.; Mahadevapuram, Rakesh; Chen, Yuqing; Anderegg, James; Chaudhary, Sumit

    2012-05-15

    Herein, the implications of silicone contamination found in solution-processed conjugated polymer solar cells are explored. Similar to a previous work based on molecular cells, we find this contamination as a result of the use of plastic syringes during fabrication. However, in contrast to the molecular case, we find that glass-syringe fabricated devices give superior performance than plastic-syringe fabricated devices in poly(3-hexylthiophene)-based cells. We find that the unintentional silicone addition alters the solution’s wettability, which translates to a thinner, less absorbent film on spinning. With many groups studying the effects of small-volume additives, this work should be closely considered as many of these additives may also directly alter the solutions’ wettability, or the amount of silicone dissolved off the plastic syringes, or both. Thereby, film thickness, which generally is not reported in detail, can vary significantly from device to device.

  17. The analysis and design of a pressure-measuring syringe utilizing elastomeric bellows

    E-print Network

    Duffley, Samuel C

    2009-01-01

    Endotracheal tube insertion requires the measurement of very low pressure. Currently, there exists no reliable method or device that is integral with the inflation syringe for measuring this pressure. Thus, a device for ...

  18. HOSPITAL- VERSUS COMMUNITY–BASED SYRINGE EXCHANGE: A RANDOMIZED CONTROLLED TRIAL

    PubMed Central

    Masson, Carmen L.; Sorensen, James L.; Perlman, David C.; Shopshire, Michael S.; Delucchi, Kevin L.; Chen, TeChieh; Sporer, Karl; Jarlais, Don Des; Hall, Sharon M.

    2013-01-01

    This study examined the effect of syringe exchange program setting on the injection practices, health status, and health service utilization patterns of injection drug users (IDUs) recruited from a public urban hospital. One hundred sixty-six participants were randomized to either community– or hospital–based syringe exchange services. Poisson regression models were used to compare service utilization between groups. In both conditions, risky drug use practices decreased, and physical health functioning improved over time. Hospital–based syringe exchange program (SEP) attendees had 83% more inpatient admissions (p < .0001) and 22% more ambulatory care visits (p < .0001) than those assigned to the community–based SEP condition. Syringe exchange services that are integrated into public hospital settings may serve as a valuable strategy to engage hard to reach IDU populations in behavioral interventions designed to reduce HIV risk transmission behaviors and increase access to, or engagement in, the use of secondary and tertiary preventive medical care. PMID:17411413

  19. Adsorption of 99mTc-Radiopharmaceuticals onto Injection Vials and Syringes

    Microsoft Academic Search

    Ahmad Mushtaq; Muhammad Safdar Mansur; Mustanser Jehangir

    2008-01-01

    Many groups have reported the adsorption or retention of 99mTc- radiopharmaceuticals on injection vials and disposable plastic syringes. Such an enormously high loss of radioactivity would re- sult in poor images, radiation exposure, waste, and economic burdens. We therefore decided to investigate the extent of ad- sorption or retention of several 99mTc-radiopharmaceuticals on injection vials,rubber stoppers, and plastic syringes. These

  20. A syringe injection rate detector employing a dual Hall-effect sensor configuration.

    PubMed

    Mukherjee, Biswarup; George, Boby; Sivaprakasam, Mohanasankar

    2013-01-01

    Injection of fluids in the body using needle syringes is a standard clinical practice. The rate of injection can have various pathological effects on the body such as the pain perceived or in case of anesthesia, the amount of akinesia attained. Hence, a training system with a modified syringe employing a simple measurement scheme where a trainee can observe and practice the rate of injection prior to administering on actual human subjects, can be of great value towards reduction of complications in real life situations. In this paper, we develop a system for measurement of syringe injection rate with two Hall-effect sensors. Ring magnets attached to the body of the syringe along with the dual Hall-effect sensor configuration help in determining the position of the piston with respect to the syringe body. The two Hall-sensors are arranged in a differential configuration such that a linear relationship is obtained between the volume of liquid in the syringe (in ml) and the Hall-effect sensor output voltages. A prototype developed validated the measurement scheme. The rate of injection was displayed in real-time with a LabVIEW based Virtual Instrument. The error was within acceptable limits illustrating its efficacy for practical training purposes. PMID:24110792

  1. Freeze-drying in novel container system: Characterization of heat and mass transfer in glass syringes.

    PubMed

    Patel, Sajal M; Pikal, Michael J

    2010-07-01

    This study is aimed at characterizing and understanding different modes of heat and mass transfer in glass syringes to develop a robust freeze-drying process. Two different holder systems were used to freeze-dry in syringes: an aluminum (Al) block and a plexiglass holder. The syringe heat transfer coefficient was characterized by a sublimation test using pure water. Mannitol and sucrose (5% w/v) were also freeze-dried, as model systems, in both the assemblies. Dry layer resistance was determined from manometric temperature measurement (MTM) and product temperature was measured using thermocouples, and was also determined from MTM. Further, freeze-drying process was also designed using Smart freeze-dryer to assess its application for freeze-drying in novel container systems. Heat and mass transfer in syringes were compared against the traditional container system (i.e., glass tubing vial). In the Al block, the heat transfer was via three modes: contact conduction, gas conduction, and radiation with gas conduction being the dominant mode of heat transfer. In the plexiglass holder, the heat transfer was mostly via radiation; convection was not involved. Also, MTM/Smart freeze-drying did work reasonably well for freeze-drying in syringes. When compared to tubing vials, product temperature decreases and hence drying time increases in syringes. PMID:20166199

  2. Syringe exchange in the United States: a national level economic evaluation of hypothetical increases in investment.

    PubMed

    Nguyen, Trang Quynh; Weir, Brian W; Des Jarlais, Don C; Pinkerton, Steven D; Holtgrave, David R

    2014-11-01

    To examine whether increasing investment in needle/syringe exchange programs (NSPs) in the US would be cost-effective for HIV prevention, we modeled HIV incidence in hypothetical cases with higher NSP syringe supply than current levels, and estimated number of infections averted, cost per infection averted, treatment costs saved, and financial return on investment. We modified Pinkerton's model, which was an adaptation of Kaplan's simplified needle circulation theory model, to compare different syringe supply levels, account for syringes from non-NSP sources, and reflect reduction in syringe sharing and contamination. With an annual $10 to $50 million funding increase, 194-816 HIV infections would be averted (cost per infection averted $51,601-$61,302). Contrasted with HIV treatment cost savings alone, the rate of financial return on investment would be 7.58-6.38. Main and sensitivity analyses strongly suggest that it would be cost-saving for the US to invest in syringe exchange expansion. PMID:24824043

  3. Evidence-Based Policy Versus Morality Policy: The Case of Syringe Access Programs.

    PubMed

    de Saxe Zerden, Lisa; O'Quinn, Erin; Davis, Corey

    2015-01-01

    Evidence-based practice (EBP) combines proven interventions with clinical experience, ethics, and client preferences to inform treatment and services. Although EBP is integrated into most aspects of social work and public health, at times EBP is at odds with social policy. In this article the authors explore the paradox of evidence-based policy using syringe access programs (SAP) as a case example, and review methods of bridging the gap between the emphasis on EBP and lack of evidence informing SAP policy. Analysis includes the overuse of morality policy and examines historical and current theories why this paradox exists. Action steps are highlighted for creating effective policy and opportunities for public health change. Strategies on reframing the problem and shifting target population focus to garner support for evidence-based policy change are included. This interdisciplinary understanding of the way in which these factors converge is a critical first step in moving beyond morality-based policy toward evidence-based policy. PMID:25747745

  4. In-syringe demulsified dispersive liquid-liquid microextraction and high performance liquid chromatography-mass spectrometry for the determination of trace fungicides in environmental water samples.

    PubMed

    Xia, Yating; Cheng, Min; Guo, Feng; Wang, Xiangfang; Cheng, Jing

    2012-04-29

    An in-syringe demulsified dispersive liquid-liquid microextraction (ISD-DLLME) technique was developed using low-density extraction solvents for the highly sensitive determination of the three trace fungicides (azoxystrobin, diethofencarb and pyrimethanil) in water samples by high performance liquid chromatography-mass spectrometry chromatography-diode array detector/electrospray ionisation mass spectrometry. In the proposed technique, a 5-mL syringe was used as an extraction, separation and preconcentration container. The emulsion was obtained after the mixture of toluene (extraction solvent) and methanol (dispersive solvent) was injected into the aqueous bulk of the syringe. The obtained emulsion cleared into two phases without centrifugation, when an aliquot of methanol was introduced as a demulsifier. The separated floating organic extraction solvent was impelled and collected into a pipette tip fitted to the tip of the syringe. Under the optimal conditions, the enrichment factors for azoxystrobin, diethofencarb and pyrimethanil were 239, 200, 195, respectively. The limits of detection, calculated as three times the signal-to-noise ratio (SN(-1)), were 0.026 ?g L(-1) for azoxystrobin, 0.071 ?g L(-1) for diethofencarb and 0.040 ?g L(-1) for pyrimethanil. The repeatability study was carried out by extracting the spiked water samples at concentration levels of 0.02 ?g mL(-1) for all the three fungicides. The relative standard deviations varied between 4.9 and 8.2% (n=5). The recoveries of all the three fungicides from tap, lake and rain water samples at spiking levels of 0.2, 1, 5 ?g L(-1) were in the range of 90.0-105.0%, 86.0-114.0% and 88.6-110.0%, respectively. The proposed ISD-DLLME technique was demonstrated to be simple, practical and efficient for the determination of different kinds of fungicide residues in real water samples. PMID:22483208

  5. The TRPA1 Agonist, Methyl Syringate Suppresses Food Intake and Gastric Emptying

    PubMed Central

    Song, Seo Hyeon; Jung, Myungji; Kim, Yiseul; Rhyu, Mee-Ra

    2013-01-01

    Transient receptor potential channel ankryn 1 (TRPA1) expressed in the gastrointestinal tract is associated with gastric motility, gastric emptying, and food intake. In this study, we investigated the effects of methyl syringate, a specific and selective TRPA1 agonist, on food intake, gastric emptying, and gut hormone levels in imprinting control region (ICR) mice. The administration of methyl syringate suppressed cumulative food intake and gastric emptying. In addition, treatment with ruthenium red (RR), a general cation channel blocker, and HC-030031, a selective TRPA1 antagonist, inhibited methyl syringate-induced reduction of food intake and delayed gastric emptying in ICR mice. Methyl syringate also increased plasma peptide YY (PYY) levels, but not glucagon-like peptide-1 (GLP-1) levels. The elevation in PYY was blocked by treatment with RR and HC-030031. The present findings indicate that methyl syringate regulates food intake and gastric emptying through a TRPA1-mediated pathway and, by extension, can contribute to weight suppression. PMID:23990963

  6. Root Cause Analysis of Tungsten-Induced Protein Aggregation in Pre-filled Syringes.

    PubMed

    Liu, Wei; Swift, Rob; Torraca, Gianni; Nashed-Samuel, Yasser; Wen, Zai-Qing; Jiang, Yijia; Vance, Aylin; Mire-Sluis, Anthony; Freund, Erwin; Davis, Janice; Narhi, Linda

    2010-01-01

    Particles isolated from a pre-filled syringe containing a protein-based solution were identified as aggregated protein and tungsten. The origin of the tungsten was traced to the tungsten pins used in the supplier's syringe barrel forming process. A tungsten recovery study showed that the vacuum stopper placement process has a significant impact on the total amount of tungsten in solutions. The air gap formed in the syringe funnel area (rich in residual tungsten) becomes accessible to solutions when the vacuum is pulled. Leachable tungsten deposits that were not removed by the supplier's wash process are concentrated in this small area. Extraction procedures used to measure residual tungsten in empty syringes would under-report the tungsten quantity unless the funnel area is wetted during the extraction. Improved syringe barrel forming and washing processes at the supplier have lowered the residual tungsten content and significantly reduced the risk of protein aggregate formation. This experience demonstrates that packaging component manufacturing processes, which are outside the direct control of drug manufacturers, can have an impact on the drug product quality. Thus close technical communication with suppliers of product contact components plays an important role in making a successful biotherapeutic. PMID:21501999

  7. Negotiating access: Social barriers to purchasing syringes at pharmacies in Tijuana, Mexico

    PubMed Central

    Davidson, Peter J.; Lozada, Remedios; Rosen, Perth C.; Macias, Armando; Gallardo, Manuel; Pollini, Robin A.

    2012-01-01

    Background One common public health response to the emergence of HIV has been the provision of sterile syringes to people who inject drugs. In Mexico specialized syringe exchanges are rare, and the sale of needles through pharmacies is often the only way people who inject drugs can obtain sterile syringes. However, people who inject drugs in Tijuana, Mexico report considerable social barriers to successfully purchasing syringes at pharmacies. Methods Between October 2008 and March 2009 we conducted seven in-depth focus groups with 47 people who inject drugs in Tijuana, Mexico. Focus group transcripts were analysed using a descriptive and thematic approach rooted in grounded theory. Results We found that injectors offered a number of explanations for why pharmacies were reluctant to sell them syringes, including fear of police; attitudes toward drug use; fear of stereotypical drug user behaviour such as petty theft, violence, or distressing behaviour; and related fears that an obvious drug using clientèle would drive away other customers. Injectors described a range of ways of attempting to re-frame or negotiate interactions with pharmacy staff so that these and related concerns were ameliorated. These included tactics as simple as borrowing cleaner clothing, through to strategies for becoming ‘known’ to pharmacy staff as an individual rather than as a member of a stigmatized group. Conclusion Increasing the ability of pharmacy staff and people who inject drugs to successfully negotiate syringe sales are highly desirable. Interventions designed to improve this likelihood need to capitalize on existing solutions developed ad-hoc by people who inject drugs and pharmacy staff, and should focus on broadening the range of ‘identities’ which pharmacy staff are able to accept as legitimate customers. Approaches to achieve this end might include sensitizing pharmacy staff to the needs of people who inject drugs; facilitating individual drug users meeting individual pharmacy staff; and working with drug users to reduce behaviours seen as problematic by pharmacy staff. PMID:22676968

  8. SAR calibration technology review

    NASA Technical Reports Server (NTRS)

    Walker, J. L.; Larson, R. W.

    1981-01-01

    Synthetic Aperture Radar (SAR) calibration technology including a general description of the primary calibration techniques and some of the factors which affect the performance of calibrated SAR systems are reviewed. The use of reference reflectors for measurement of the total system transfer function along with an on-board calibration signal generator for monitoring the temporal variations of the receiver to processor output is a practical approach for SAR calibration. However, preliminary error analysis and previous experimental measurements indicate that reflectivity measurement accuracies of better than 3 dB will be difficult to achieve. This is not adequate for many applications and, therefore, improved end-to-end SAR calibration techniques are required.

  9. Community Impact of Pharmacy-Randomized Intervention to Improve Access to Syringes and Services for Injection Drug Users

    ERIC Educational Resources Information Center

    Crawford, Natalie D.; Amesty, Silvia; Rivera, Alexis V.; Harripersaud, Katherine; Turner, Alezandria; Fuller, Crystal M.

    2014-01-01

    Objectives: In an effort to reduce HIV transmission among injection drug users (IDUs), New York State deregulated pharmacy syringe sales in 2001 through the Expanded Syringe Access Program by removing the requirement of a prescription. With evidence suggesting pharmacists' ability to expand their public health role, a structural,…

  10. In-syringe-stirring: a novel approach for magnetic stirring-assisted dispersive liquid-liquid microextraction.

    PubMed

    Horstkotte, Burkhard; Suárez, Ruth; Solich, Petr; Cerdà, Víctor

    2013-07-25

    For the first time, the use of a magnetic stirrer within the syringe of an automated syringe pump and the resulting possible analytical applications are described. A simple instrumentation following roughly the one from sequential injection analyzer systems is used in combination with an adaptor, which is placed onto the barrel of a glass syringe. Swirling around the longitudinal axis of the syringe and holding two strong neodymium magnets, it causes a rotating magnetic field and serves as driver for a magnetic stirring bar placed inside of the syringe. In a first study it was shown that this approach leads to a sealed but also automatically adaptable reaction vessel, the syringe, in which rapid and homogeneous mixing of sample with the required reagents within short time can be carried out. In a second study in-a-syringe magnetic stirring-assisted dispersive liquid-liquid microextraction (MSA-DLLME) was demonstrated by the application of the analyzer system to fluorimetric determination of aluminum in seawater samples using lumogallion. A linear working range up to 1.1 ?mol L(-1) and a limit of detection of 6.1 nmol L(-1) were found. An average recovery of 106.0% was achieved for coastal seawaters with a reproducibility of 4.4%. The procedure lasted 210 s including syringe cleaning and only 150 ?L of hexanol and 4.1 mL of sample were required. PMID:23845481

  11. Microextraction in a packed syringe for the analysis of olive biophenols in rat plasma using CMK-3 nanoporous sorbent.

    PubMed

    Khoshdel, Zeynab; Hashemi, Payman; Safdaryan, Mehdi; Delfan, Bahram; Rashidipour, Marzieh; Badiei, Alireza

    2013-01-01

    A carbon-based nanoporous sorbent was first used for microextraction in a packed syringe (MEPS) before HPLC/UV analysis of some biophenols in rat plasma. A laboratory-made programmable apparatus was designed and used for automation of the extraction procedure. The MEPS syringe was packed with 2 mg of CMK-3 sorbent, between the barrel and the injection needle, and mounted on an apparatus for programming of the conditioning, sampling, washing, elution and cleaning steps. All steps of the microextraction procedure were carefully optimized on the system. For optimization of important factors, such as the number of adsorption and elution cycles, elution volume and pH, a multivariate central composite design method was used. The highest recoveries were obtained for 24 and 10 times of adsorption and elution cycles, respectively, using 100 ?L of acetonitrile as the eluent and a sample pH of 2. Good results were obtained in terms of the precision (RSD 1.6, 2.5 and 2.3%) and detection limit (0.7, 4.7 and 0.25 ?M) for caffeic acid, tyrsol and oleuropein, respectively. The method was simple, efficient and appropriate for sample clean up before analysis by HPLC, and was successfully applied to the determination of biophenols in the plasma of several rats that received an olive leaves extract either by a gavage or an intraperitoneal injection method. A positive correlation was found between the amount of olive extract's feeding of the rats and the level of their plasma biophenols. PMID:23665625

  12. Using syringe drivers in palliative care within a rural, community setting: capturing the whole experience.

    PubMed

    Cruickshank, Susanne; Adamson, Elizabeth; Logan, Janice; Brackenridge, Katie

    2010-03-01

    The aim of this research was to understand how the introduction of a syringe driver, which is considered routine practice in many palliative care settings, impacted on patients, carers and community nurses within a rural, community setting. A phenomenological study was conducted exploring the experiences from the perspective of patients (n=4), carers (n=9) and community nurses (n=12) when syringe drivers are used at home. We interviewed patients and carers in their own homes and conducted two focus groups with community nurses who had an interest in palliative care but were not specialists. Despite the wide use of syringe drivers within palliative care, our study found their use among community nurses, particularly in rural areas can be variable with frequent time lapses between a nurse's exposure, impacting on both their technical abilities and knowledge. In-depth interviews with patients revealed few barriers to their use, but carers clearly identified areas where their expectations and experiences differed and where more information setting realistic goals of care would have been helpful. The authors conclude that although nurses require competencies related to syringe drivers, they also need an in-depth knowledge of the actions of the drugs and the likely changes which occur physiologically as patients approach the end of their life. This will ensure accurate information is delivered, and facilitate meaningful dialogue. PMID:20357705

  13. Residual Injection Risk Behavior, HIV Infection, and the Evaluation of Syringe Exchange Programs

    ERIC Educational Resources Information Center

    Des Jarlais, Don C.; Braine, Naomi; Yi, Huso; Turner, Charles

    2007-01-01

    This study assessed relationships between residual risk behavior (risk behavior among persons participating in effective HIV prevention programs) and HIV infection. Structured interviews and HIV tests were obtained from participants in six large U.S. syringe exchange programs. Program characteristics were obtained through interviews with the…

  14. Detection of tissue properties using a piezoelectric vibration-based syringe

    NASA Astrophysics Data System (ADS)

    Lin, C. H.; Huang, Y. C.; Tsai, M. C.

    2012-12-01

    For safety improvement purposes, detection of tissue properties at the tip of the needle in real-time is helpful in controlling the movement of the needle in the operation of invasive surgical tools. According to the energy-based force model, the mechanical impedance of tissue can be represented approximately by a spring-damping model. In this study, a vibration-based syringe which adopts piezoelectric elements to vibrate the needle is proposed to identify tissue properties. In principle, by measuring the input electrical impedance of the vibration-based syringe, the mechanical impedance of tissue can be detected indirectly while the syringe exerts a vibration on the tissue. The model of the piezoelectric driven syringe and the procedure for evaluating the electromechanical interaction are given, and the mechanical impedance of tissue is evaluated by simulation. The proposed detection method has potential for applications of identifying tissue properties in epidural punctures and estimation of the degree of ablation in thermal surgery systems.

  15. Chemicals and Energy from Medical Polymer Wastes I. Pyrolysis of Disposable Syringes

    Microsoft Academic Search

    C. Vasile; M. Brebu; H. Darie; R. D. Deanin; V. Dorneanu; D. M. Pantea; O. G. Ciochina

    1997-01-01

    The pyrolysis of the disposable syringes has been studied and reaction products have been characterized by gas-chromatography, density, refractive indices, aniline point analysis and spectroscopic methods. It has been concluded that pyrolysis offers a solution for treatment of this kind of medical polymer wastes and fuels and\\/or chemicals can be obtained.

  16. Autologous fat grafting: use of closed syringe microcannula system for enhanced autologous structural grafting

    PubMed Central

    Alexander, Robert W; Harrell, David B

    2013-01-01

    Objectives Provide background for use of acquiring autologous adipose tissue as a tissue graft and source of adult progenitor cells for use in cosmetic plastic surgery. Discuss the background and mechanisms of action of closed syringe vacuum lipoaspiration, with emphasis on accessing adipose-derived mesenchymal/stromal cells and the stromal vascular fraction (SVF) for use in aesthetic, structural reconstruction and regenerative applications. Explain a proven protocol for acquiring high-quality autologous fat grafts (AFG) with use of disposable, microcannula systems. Design Explain the components and advantage of use of the patented super luer-lock and microcannulas system for use with the closed-syringe system. A sequential explanation of equipment selection for minimally traumatic lipoaspiration in small volumes is presented, including use of blunt injection cannulas to reduce risk of embolism. Results Thousands of AFG have proven safe and efficacious for lipoaspiration techniques for large and small structural fat grafting procedures. The importance and advantages of gentle harvesting of the adipose tissue complex has become very clear in the past 5 years. The closed-syringe system offers a minimally invasive, gentle system with which to mobilize subdermal fat tissues in a suspension form. Resulting total nuclear counting of undifferentiated cells of the adipose-derived -SVF suggests that the yield achieved is better than use of always-on, constant mechanical pump applied vacuum systems. Conclusion Use of a closed-syringe lipoaspiration system featuring disposable microcannulas offers a safe and effective means of harvesting small volumes of nonmanipulated adipose tissues and its accompanying progenitor cells within the SVF. Closed syringes and microcannulas are available as safe, sterile, disposable, compact systems for acquiring high-quality AFG. Presented is a detailed, step-by-step, proven protocol for performing quality autologous structural adipose transplantation. PMID:23630430

  17. Safety, effectiveness and ease of use of a non-reusable syringe in a developing country immunization programme.

    PubMed Central

    Steinglass, R.; Boyd, D.; Grabowsky, M.; Laghari, A. G.; Khan, M. A.; Qavi, A.; Evans, P.

    1995-01-01

    Unsterile needles and syringes may transmit blood-borne infectious agents such as HIV and hepatitis B virus. The emergence of these diseases as major public health concerns and the risk of nosocomial transmission has heightened interest in the development of single-use injection devices. WHO and UNICEF embarked on a programme to develop and introduce these devices in 1987. We report on a field trial in Karachi, Pakistan, of the SoloShot (SS) plastic disposable syringe, which has a metal clip in the syringe barrel to prevent second-time withdrawal of the plunger. A conventional disposable syringe (CS) was used as a comparison. We observed 48 vaccinators giving 2400 injections with the SS and 1440 with the CS; 98.7% of SS performed as designed. The average volume required per delivered dose was comparable for the two syringes and was delivered more quickly with SS. Training and experience had a small but statistically significant effect on several aspects of SS use. Vaccinators who indicated a syringe preference preferred SS on 7 out of 9 indicators. SS is safe and effective in preventing reuse and is easier and quicker to use than the CS. Vaccinators require little, if any, special training. It could directly replace disposable syringes in expanded programmes on immunization (EPI) in countries where use of unsterile disposable devices occurs or when sterilization is not practical. PMID:7704926

  18. Community Impact of Pharmacy-Randomized Intervention to Improve Access to Syringes and Services for Injection Drug Users.

    PubMed

    Crawford, Natalie D; Amesty, Silvia; Rivera, Alexis V; Harripersaud, Katherine; Turner, Alezandria; Fuller, Crystal M

    2014-04-10

    Objectives. In an effort to reduce HIV transmission among injection drug users (IDUs), New York State deregulated pharmacy syringe sales in 2001 through the Expanded Syringe Access Program by removing the requirement of a prescription. With evidence suggesting pharmacists' ability to expand their public health role, a structural, pharmacy-based intervention was implemented to determine whether expanding pharmacy practice to include provision of HIV risk reduction and social/medical services information during the syringe sale would (a) improve pharmacy staff attitudes toward IDUs (b) increase IDU syringe customers, and (c) increase prescription customer base in New York City neighborhoods with high burden of HIV and illegal drug activity. Methods. Pharmacies (n = 88) were randomized into intervention (recruited IDU syringe customers into the study and delivered intervention activities), primary control (recruited IDU syringe customers only) and secondary control (did not recruit IDUs or deliver intervention activities) arms. Results. Pharmacy staff in the intervention versus secondary control pharmacies showed significant decreases in the belief that selling syringes to IDUs causes community loitering. Conclusions. Structural interventions may be optimal approaches for changing normative attitudes about highly stigmatized populations. PMID:24722219

  19. Associations of serum insulin-like growth factor-I and insulin-like growth factor-binding protein 3 levels with biomarker-calibrated protein, dairy product and milk intake in the Women's Health Initiative.

    PubMed

    Beasley, Jeannette M; Gunter, Marc J; LaCroix, Andrea Z; Prentice, Ross L; Neuhouser, Marian L; Tinker, Lesley F; Vitolins, Mara Z; Strickler, Howard D

    2014-03-14

    It is well established that protein-energy malnutrition decreases serum insulin-like growth factor (IGF)-I levels, and supplementation of 30 g of whey protein daily has been shown to increase serum IGF-I levels by 8 % after 2 years in a clinical trial. Cohort studies provide the opportunity to assess associations between dietary protein intake and IGF axis protein levels under more typical eating conditions. In the present study, we assessed the associations of circulating IGF axis protein levels (ELISA, Diagnostic Systems Laboratories) with total biomarker-calibrated protein intake, as well as with dairy product and milk intake, among postmenopausal women enrolled in the Women's Health Initiative (n 747). Analyses were carried out using multivariate linear regression models that adjusted for age, BMI, race/ethnicity, education, biomarker-calibrated energy intake, alcohol intake, smoking, physical activity and hormone therapy use. There was a positive association between milk intake and free IGF-I levels. A three-serving increase in milk intake per d (approximately 30 g of protein) was associated with an estimated average 18·6 % higher increase in free IGF-I levels (95 % CI 0·9, 39·3 %). However, total IGF-I and insulin-like growth factor-binding protein 3 (IGFBP-3) levels were not associated with milk consumption and nor were there associations between biomarker-calibrated protein intake, biomarker-calibrated energy intake, and free IGF-I, total IGF-I or IGFBP-3 levels. The findings of the present study carried out in postmenopausal women are consistent with clinical trial data suggesting a specific relationship between milk consumption and serum IGF-I levels, although in the present study this association was only statistically significant for free, but not total, IGF-I or IGFBP-3 levels. PMID:24094144

  20. Hand-powered microfluidics: A membrane pump with a patient-to-chip syringe interface

    NASA Astrophysics Data System (ADS)

    MacDonald, Brendan; Gong, Max; Nguyen, Trung; Sinton, David

    2012-11-01

    In this talk, an on-chip hand-powered membrane pump with a robust patient-to-chip syringe interface is presented. This approach enables safe sample collection, sample containment, integrated sharps disposal, high sample volume capacity, and controlled downstream flow with no electrical power requirements. Sample is manually injected into the device via a syringe and needle. The membrane pump inflates upon injection and subsequently deflates, delivering fluid to downstream components in a controlled manner. The device is fabricated from poly(methyl methacrylate) (PMMA) and silicone, using CO2 laser micromachining. Pump performance is experimentally demonstrated and the behavior is subsequently modeled with reference to a resistor-capacitor electrical circuit analogy. Downstream output of the membrane pump is regulated, and scaled, by connecting multiple pumps in parallel. The device provides precisely controlled pumping rates and high volume throughput without any electrical power requirements.

  1. Atmospheric Pressure Cold Argon/Oxygen Plasma Jet Assisted by Preionization of Syringe Needle Electrode

    NASA Astrophysics Data System (ADS)

    Qian, Muyang; Ren, Chunsheng; Wang, Dezhen; Feng, Yan; Zhang, Jialiang

    2010-10-01

    An atmospheric pressure nonequilibrium argon/oxygen plasma jet assisted by the preionization of syringe needle electrode discharge is reported. With the syringe needle plasma as its pre-ionization source, the hybrid barrier-jet was shown to generate uniform discharge with a lower breakdown voltage and a relatively low gas temperature varying from 390 K to 440 K, even when the vol.% oxygen in argon was up to 6%. Utilizing the actinometry method, the concentration of atomic oxygen was estimated to be about in an orders of magnitude of 1017 cm-3. The argon/oxygen plasma jet was then employed to clean out heat transfer oil, with a maximum cleaning rate of 0.1 mm/s achieved.

  2. Micron-Scale Droplet Deposition on a Hydrophobic Surface Using a Retreating Syringe

    NASA Astrophysics Data System (ADS)

    Qian, Bian; Loureiro, Melissa; Gagnon, David A.; Tripathi, Anubhav; Breuer, Kenneth S.

    2009-04-01

    Droplet deposition onto a hydrophobic surface is studied experimentally and numerically. A wide range of droplet sizes can result from the same syringe, depending strongly on the needle retraction speed. Three regimes are identified according to the motion of the contact line. In region I, at slow retraction speeds, the contact line expands and large droplets can be achieved. In region II, at moderate needle speeds, a quasicylindrical liquid bridge forms resulting in drops approximately the size of the needle. Finally, at high speeds (region III), the contact line retracts and droplets much smaller than the syringe diameter are observed. Scaling arguments are presented identifying the dominant mechanisms in each regime. Results from nonlinear numerical simulations agree well with the experiments, although the accuracy of the predictions is limited by inadequate models for the behavior of the dynamic contact angle.

  3. Appropriate sample bags and syringes for preserving breath samples in breath odor research: a technical note.

    PubMed

    Winkel, E G; Tangerman, A

    2008-03-01

    It is now generally accepted that the volatile sulfur compounds (VSCs) hydrogen sulfide, methyl mercaptan and dimethyl sulfide are the main contributors to halitosis when of oropharyngeal origin. The VSCs hydrogen sulfide and methyl mercaptan are the major causes of bad breath in oral malodour whereas dimethyl sulfide is generally the major cause of bad breath in extra-oral halitosis. To facilitate research in the field of halitosis, it is highly advantageous to be able to preserve breath samples for longer periods of time before measurement of the VSCs, e.g. for sampling patients at home or when studying a large cohort of patients where an immediate measurement of the VSCs is not possible. After testing numerous sample bags, ultimately the foil balloons, coated inside with the synthetic polymer polyethylene, were the preferred ones. All the VSCs in breath remained quite stable for at least 3 days in these balloons. Besides the sampling bags, the use of an appropriate syringe for sampling mouth air and for injecting samples in e.g. a gas chromatograph is also of great importance. Usually, syringes with a rubber barrel seal are used. However, some rubbers quickly adsorb the VSCs in breath. When preserving breath samples for longer periods, the rubber also releases VSCs, especially methyl mercaptan. It was also found that these syringes release a compound which interferes with dimethyl sulfide, when using gas chromatographic measurements with the OralChroma. We now use all-plastic syringes (B/Braun Injekt), made of polypropylene and polyethylene, in which the VSCs in breath remain quite stable for at least 9 h. PMID:21386155

  4. MODIS calibration

    NASA Technical Reports Server (NTRS)

    Barker, John L.

    1992-01-01

    The MODIS/MCST (MODIS Characterization Support Team) Status Report contains an outline of the calibration strategy, handbook, and plan. It also contains an outline of the MODIS/MCST action item from the 4th EOS Cal/Val Meeting, for which the objective was to locate potential MODIS calibration targets on the Earth's surface that are radiometrically homogeneous on a scale of 3 by 3 Km. As appendices, draft copies of the handbook table of contents, calibration plan table of contents, and detailed agenda for MODIS calibration working group are included.

  5. Calibration techniques for VLBI

    Microsoft Academic Search

    J. M. Moran; V. Dhawan

    1995-01-01

    Introduction; Delay Calibration; Fringe-Rate Calibration; Amplitude Calibration; Antenna Calibration; Atmospheric Opacity; Phase Calibration; Coherent and Incoherent Averaging; Atmospheric Effects on Phase and Delay; Phased Arrays as VLBI Elements; The Impact of Calibration Errors in Images; Summary

  6. SU-E-I-22: Dependence On Calibration Phantom and Field Area of the Conversion Factor Used to Calculate Skin Dose During Neuro-Interventional Fluoroscopic Procedures

    SciTech Connect

    Rana, V K; Vijayan, S [Physiology and Biophysics, Toshiba Stroke and Vascular Research Center, University at Buffalo (State University of New York), Buffalo, NY (United States); Rudin, S R; Bednarek, D R [Department of Radiology, Physiology and Biophysics, Toshiba Stroke and Vascular Research Center, University at Buffalo (State University of New York), Buffalo, NY (United States)

    2014-06-01

    Purpose: To determine the appropriate calibration factor to use when calculating skin dose with our real-time dose-tracking system (DTS) during neuro-interventional fluoroscopic procedures by evaluating the difference in backscatter from different phantoms and as a function of entrance-skin field area. Methods: We developed a dose-tracking system to calculate and graphically display the cumulative skin-dose distribution in real time. To calibrate the DTS for neuro-interventional procedures, a phantom is needed that closely approximates the scattering properties of the head. We compared the x-ray backscatter from eight phantoms: 20-cm-thick solid water, 16-cm diameter water-filled container, 16-cm CTDI phantom, modified-ANSI head phantom, 20-cm-thick PMMA, Kyoto-Kagaku PBU- 50 head, Phantom-Labs SK-150 head, and RSD RS-240T head. The phantoms were placed on the patient table with the entrance surface at 15 cm tube-side from the isocenter of a Toshiba Infinix C-arm, and the entrance-skin exposure was measured with a calibrated 6-cc PTW ionization chamber. The measurement included primary radiation, backscatter from the phantom and forward scatter from the table and pad. The variation in entrance-skin exposure was also measured as a function of the skin-entrance area for a 30x30 cm by 20-cm-thick PMMA phantom and the SK-150 head phantom using four different added beam filters. Results: The entranceskin exposure values measured for eight different phantoms differed by up to 12%, while the ratio of entrance exposure of all phantoms relative to solid water showed less than 3% variation with kVp. The change in entrance-skin exposure with entrance-skin area was found to differ for the SK-150 head compared to the 20-cm PMMA phantom and the variation with field area was dependent on the added beam filtration. Conclusion: To accurately calculate skin dose for neuro-interventional procedures with the DTS, the phantom for calibration should be carefully chosen since different phantoms can contribute different backscatter for identical exposure parameters. Research supported in part by Toshiba Medical Systems and NIH Grants R43FD0158401, R44FD0158402 and R01EB002873.

  7. Taste and/or Odour Disturbances in Pediatric Patients Undergoing IV Flush with Normal Saline Administered by Prefilled Syringe

    PubMed Central

    Celetti, Steven J; Vaillancourt, Régis; Pascuet, Elena; Sharp, Diane

    2012-01-01

    Background: At the Children’s Hospital of Eastern Ontario, more than 6000 inpatients per year undergo IV saline flushes by prefilled syringe to assess and maintain patency of IV tubing. In studies involving adults, it has been reported that volatile substances may leach from syringe materials into the saline, leading to taste and/or odour disturbances. Objective: To determine the incidence of taste and/or odour disturbances in pediatric patients after flushing of IV tubing with 0.9% sodium chloride (normal saline [NS]) from prefilled syringes. Methods: Inpatients aged 5–18 years who had undergone routine flushing of central or peripheral IV tubing with commercially available prefilled NS syringes were interviewed. Children aged 5–10 years used a visual hedonic scale to rate taste and odour sensations, and those aged 11–18 years used a numeric rating scale. Results: During the study period (April to July 2011), a total of 104 pediatric inpatients (21 aged 5–10 years and 83 aged 11–18 years) underwent NS flushing of central (10 patients [10%]) or peripheral (94 patients [90%]) tubing. For 100 of these patients, BD Posiflush NaCl 0.9% 10-mL sterile prefilled syringes were used, and for 4 patients BD Saline XS NaCl 0.9% 10-mL sterile prefilled syringes were used. Taste and/or odour disturbances were reported by 76 (73%) of the patients. Twelve patients described more than one taste or odour sensation. Taste and odour disturbances were detected by children in both age groups. Conclusions: Flushing of IV tubing with prefilled NS syringes resulted in taste and/or odour disturbances in a pediatric population. PMID:23129865

  8. Oxygen atomic density of atmospheric Ar plasma jet generated with syringe needle-ring electrodes

    NASA Astrophysics Data System (ADS)

    Hong, Y.; Li, J.; Pan, J.; Lu, N.; Shang, K. F.; Wu, Y.

    2013-03-01

    Atmospheric-pressure argon plasma jet is generated with syringe needle-ring electrodes in an 8 kHz sinusoidal excitation voltage. It is found that the rotational temperature of nitrogen is in the range of 333 - 373 K obtained by comparing the simulated spectrum with the measured spectrum at the C3?u ? B3?g (?v = -2) band transition, the electronic excitation temperature is in the range of 3187 - 3243 K determined by the Boltzmann's plot method, and the oxygen atomic density is in the order of magnitude of 1016 cm-3 estimated by the actinometry method, respectively.

  9. Primary and secondary analysis of local elected officials' decisions to support or oppose pharmacy sale of syringes in California.

    PubMed

    Backes, Glenn; Rose, Valerie J

    2010-07-01

    Under California law, local governments may authorize pharmacies within their jurisdictions to sell ten or fewer syringes to an adult without prescription, proof of identity, or proof of medical need. Local governments may simultaneously exempt adults from prosecution for violation of state drug paraphernalia codes for possession of ten or fewer syringes for personal use. Both of these provisions are temporary and sunset on December 31, 2010, unless subsequent state legislation amends that date. The objective of our study was to ascertain how and why local policymakers made their decisions regarding non-prescription syringe sale (NPSS). We examined influences on their decisions, including specific messengers and the arguments that were most salient to their decision making. We selected jurisdictions that were geographically representative of California counties; those with and without syringe exchange programs, and those that had passed or rejected NPSS. We conducted nine semi-structured interviews in five jurisdictions. To enrich primary data collection, we analyzed secondary data by reviewing audio, video, and written transcripts of public hearings and newspaper coverage in five jurisdictions, including three jurisdictions without primary interview data. Among proponents of NPSS, we identified common themes, including: (1) public health research provided conclusive evidence for reduction in HIV and hepatitis transmission without problems of crime, drug use, or unsafe discard of syringes; (2) the local health officer was the key to influencing local policymakers; (3) recall of prior debates over syringe exchange served to inform their decision making; and (4) a lack of local opposition or controversy. Common concerns among opponents of NPSS included: (1) that there would be an increase in unsafe discard of syringes; (2) loss of an important law enforcement tool; (3) that drug users were incapable of desired behavior change; and (4) that research was inconclusive, or proved that syringe access would not work in reducing rates of disease. Themes held in common by proponents and opponents of NPSS were identified as well. Syringe access through NPSS is in fact supported by a robust body of public health research and is considered an important component of a comprehensive strategy to reduce HIV and hepatitis transmission. Our study highlights the importance of understanding the perspectives of elected officials in order to ameliorate their concerns without undermining the public health goal of reducing death, disease, and suffering in at-risk communities. PMID:20352356

  10. Flight calibration assessment of HiRAP accelerometer data

    Microsoft Academic Search

    Robert C. Blanchard; Kevin T. Larman; Christina D. Moast

    1993-01-01

    A flight derived method of calibrating the High Resolution Accelerometer Package (HiRAP) flight data has been developed and is discussed for Shuttle Orbiter missions STS-35 and STS-40. These two mission data sets have been analyzed using ground calibration factors and flight derived calibration factors. This flight technique evolved early in the flight program when it was recognized that ground calibration

  11. Hand-powered microfluidics: A membrane pump with a patient-to-chip syringe interface

    PubMed Central

    Gong, Max M.; MacDonald, Brendan D.; Vu Nguyen, Trung; Sinton, David

    2012-01-01

    In this paper, we present an on-chip hand-powered membrane pump using a robust patient-to-chip syringe interface. This approach enables safe sample collection, sample containment, integrated sharps disposal, high sample volume capacity, and controlled downstream flow with no electrical power requirements. Sample is manually injected into the device via a syringe and needle. The membrane pump inflates upon injection and subsequently deflates, delivering fluid to downstream components in a controlled manner. The device is fabricated from poly(methyl methacrylate) (PMMA) and silicone, using CO2 laser micromachining, with a total material cost of ?0.20 USD/device. We experimentally demonstrate pump performance for both deionized (DI) water and undiluted, anticoagulated mouse whole blood, and characterize the behavior with reference to a resistor-capacitor electrical circuit analogy. Downstream output of the membrane pump is regulated, and scaled, by connecting multiple pumps in parallel. In contrast to existing on-chip pumping mechanisms that typically have low volume capacity (?5??L) and sample volume throughput (?1–10??l/min), the membrane pump offers high volume capacity (up to 240??l) and sample volume throughput (up to 125??l/min). PMID:24143160

  12. Field calibration of multi-scattering correction factor for aethalometer aerosol absorption coefficient during CAPMEX Campaign, 2008

    NASA Astrophysics Data System (ADS)

    Kim, J. H.; Kim, S. W.; Yoon, S. C.; Park, R.; Ogren, J. A.

    2014-12-01

    Filter-based instrument, such as aethalometer, is being widely used to measure equivalent black carbon(EBC) mass concentration and aerosol absorption coefficient(AAC). However, many other previous studies have poited that AAC and its aerosol absorption angstrom exponent(AAE) are strongly affected by the multi-scattering correction factor(C) when we retrieve AAC from aethalometer EBC mass concentration measurement(Weingartner et al., 2003; Arnott et al., 2005; Schmid et al., 2006; Coen et al., 2010). We determined the C value using the method given in Weingartner et al. (2003) by comparing 7-wavelngth aethalometer (AE-31, Magee sci.) to 3-wavelength Photo-Acoustic Soot Spectrometer (PASS-3, DMT) at Gosan climate observatory, Korea(GCO) during Cheju ABC plume-asian monsoon experiment(CAPMEX) campaign(August and September, 2008). In this study, C was estimated to be 4.04 ± 1.68 at 532 nm and AAC retrieved with this value was decreased as approximately 100% as than that retrieved with soot case value from Weingartner et al (2003). We compared the AAC determined from aethalomter measurements to that from collocated Continuous Light Absorption Photometer (CLAP) measurements from January 2012 to December 2013 at GCO and found good agreement in both AAC and AAE. This result suggests the determination of site-specific C is crucially needed when we calculate AAC from aethalometer measurements.

  13. Effect of air moisture content on adhesion to dentine: a comparison of dental air/water syringe tips.

    PubMed

    Lau, A; Bennani, V; Chandler, N; Hanlin, S; Lowe, B

    2014-09-01

    This study aimed to evaluate the spray pattern and air moisture content produced by single-use syringe and multiple-use syringe tips. The drying efficacy was evaluated by analyzing the spray and by detecting the presence of moisture in the air blast through the tips. Single-use tips had a more consistent spray pattern and produced a moisture-free airflow compared to the multiple-use tips. The differences were statistically significant. Adhesion to dentine between tooth preparations dried with the two tips was evaluated using a tensile test. The differences were statistically insignificant. PMID:25831716

  14. GENERALIZED CALIBRATION

    E-print Network

    work is done using NIR-spectra for gasoline and wheat. Keywords Calibration, NIR spectroscopy, linear;5 Contents 1 Introduction 9 2 Gasoline example 11 2.1 Data . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 4.1.1 Model selection by cross-validation . . . . . . . . . . 26 4.2 MLLS applied to gasoline

  15. Pseudo Linear Gyro Calibration

    NASA Technical Reports Server (NTRS)

    Harman, Richard; Bar-Itzhack, Itzhack Y.

    2003-01-01

    Previous high fidelity onboard attitude algorithms estimated only the spacecraft attitude and gyro bias. The desire to promote spacecraft and ground autonomy and improvements in onboard computing power has spurred development of more sophisticated calibration algorithms. Namely, there is a desire to provide for sensor calibration through calibration parameter estimation onboard the spacecraft as well as autonomous estimation on the ground. Gyro calibration is a particularly challenging area of research. There are a variety of gyro devices available for any prospective mission ranging from inexpensive low fidelity gyros with potentially unstable scale factors to much more expensive extremely stable high fidelity units. Much research has been devoted to designing dedicated estimators such as particular Extended Kalman Filter (EKF) algorithms or Square Root Information Filters. This paper builds upon previous attitude, rate, and specialized gyro parameter estimation work performed with Pseudo Linear Kalman Filter (PSELIKA). The PSELIKA advantage is the use of the standard linear Kalman Filter algorithm. A PSELIKA algorithm for an orthogonal gyro set which includes estimates of attitude, rate, gyro misalignments, gyro scale factors, and gyro bias is developed and tested using simulated and flight data. The measurements PSELIKA uses include gyro and quaternion tracker data.

  16. Calibrated FMRI.

    PubMed

    Hoge, Richard D

    2012-08-15

    Functional magnetic resonance imaging with blood oxygenation level-dependent (BOLD) contrast has had a tremendous influence on human neuroscience in the last twenty years, providing a non-invasive means of mapping human brain function with often exquisite sensitivity and detail. However the BOLD method remains a largely qualitative approach. While the same can be said of anatomic MRI techniques, whose clinical and research impact has not been diminished in the slightest by the lack of a quantitative interpretation of their image intensity, the quantitative expression of BOLD responses as a percent of the baseline T2*- weighted signal has been viewed as necessary since the earliest days of fMRI. Calibrated MRI attempts to dissociate changes in oxygen metabolism from changes in blood flow and volume, the latter three quantities contributing jointly to determine the physiologically ambiguous percent BOLD change. This dissociation is typically performed using a "calibration" procedure in which subjects inhale a gas mixture containing small amounts of carbon dioxide or enriched oxygen to produce changes in blood flow and BOLD signal which can be measured under well-defined hemodynamic conditions. The outcome is a calibration parameter M which can then be substituted into an expression providing the fractional change in oxygen metabolism given changes in blood flow and BOLD signal during a task. The latest generation of calibrated MRI methods goes beyond fractional changes to provide absolute quantification of resting-state oxygen consumption in micromolar units, in addition to absolute measures of evoked metabolic response. This review discusses the history, challenges, and advances in calibrated MRI, from the personal perspective of the author. PMID:22369993

  17. Multiresidue determination of pesticides from aquatic media using polyaniline nanowires network as highly efficient sorbent for microextraction in packed syringe.

    PubMed

    Bagheri, Habib; Alipour, Noshin; Ayazi, Zahra

    2012-08-31

    A simple, rapid and sensitive method based on microextraction in packed syringe (MEPS), in combination with gas chromatography-mass spectrometry (GC-MS) was developed. Polyaniline (PANI) nanowires network was synthesized and used as sorbent of MEPS for the multiresidue determination of selected analytes from triazine, organochlrorine and organophosphorous pesticides in aqueous samples. The PANI nanowires network was prepared using soft template technique and its characterization was studied by scanning electron microscopy (SEM). The presence of micelles in this methodology showed to be an important parameter in shaping the growing polymer. Hexadecyltrimethylammonium bromide (HTAB) was used as structure directing agent in PANI preparation procedure and this was led to the formation of nanowires with diameters ranging from 35 nm to 45 nm. The synthesized PANI nanowires network showed higher extraction capability in comparison with the bulk PANI. Important parameters influencing the extraction and desorption processes including desorption solvent, elution volume, draw-eject cycles of sample, draw-eject mode, pH effect and amount of sorbent were optimized. Limits of detection were in the range of 0.07-0.3 ng mL(-1) using time scheduled selected ion monitoring (SIM) mode. The linearity of method was in the range from 0.5-200 ng mL(-1) to 0.2-1000 ng mL(-1). The method precision (RSD %) with three replicates were in the range of 5.3-18.4% at the concentration level of 5 ng mL(-1). The developed method was successfully applied to the Zayandeh-rood river water samples and the matrix factor obtained for the spiked real water samples were in the range of 0.79-0.94. PMID:22840649

  18. Using Pharmacies in a Structural Intervention to Distribute Low Dead Space Syringes to Reduce HIV and HCV Transmission in People Who Inject Drugs

    PubMed Central

    Johnson, Terence L.; Zule, William A.; Carda-Auten, Jessica; Golin, Carol E.

    2015-01-01

    Ongoing injection drug use contributes to the HIV and HCV epidemics in people who inject drugs. In many places, pharmacies are the primary source of sterile syringes for people who inject drugs; thus, pharmacies provide a viable public health service that reduces blood-borne disease transmission. Replacing the supply of high dead space syringes with low dead space syringes could have far-reaching benefits that include further prevention of disease transmission in people who inject drugs and reductions in dosing inaccuracies, medication errors, and medication waste in patients who use syringes. We explored using pharmacies in a structural intervention to increase the uptake of low dead space syringes as part of a comprehensive strategy to reverse these epidemics. PMID:25880955

  19. Antenna Calibration and Measurement Equipment

    NASA Technical Reports Server (NTRS)

    Rochblatt, David J.; Cortes, Manuel Vazquez

    2012-01-01

    A document describes the Antenna Calibration & Measurement Equipment (ACME) system that will provide the Deep Space Network (DSN) with instrumentation enabling a trained RF engineer at each complex to perform antenna calibration measurements and to generate antenna calibration data. This data includes continuous-scan auto-bore-based data acquisition with all-sky data gathering in support of 4th order pointing model generation requirements. Other data includes antenna subreflector focus, system noise temperature and tipping curves, antenna efficiency, reports system linearity, and instrument calibration. The ACME system design is based on the on-the-fly (OTF) mapping technique and architecture. ACME has contributed to the improved RF performance of the DSN by approximately a factor of two. It improved the pointing performances of the DSN antennas and productivity of its personnel and calibration engineers.

  20. Cold-laser microsurgery of the retina with a syringe-guided 193 nm excimer laser

    NASA Astrophysics Data System (ADS)

    Lewis, Aaron; Palanker, Daniel V.; Hemo, Itzhak; Pe'er, Jacob; Zauberman, Hanan

    1991-06-01

    This paper presents a methodology for guiding a radiation of ArF excimer laser in a liquid surrounding and confining it to the spots that can be varied in dimension from submicron diameters to tens and hundreds of microns. The approach described here is to confine and guide the excimer laser with variable diameter tapered tubes, thus opening the possibility of applying this laser in vitro-retinal surgery using endo laser techniques. Presently because of a lack of methods to guide the 193 nm ArF radiation in liquid this laser is used exclusively in ophthalmology in topical applications such as in corneal sculpturing. The methodology presented in this paper resolves this problem in a unique way and with impressive results. Specifically, the authors show that with this syringe needle guided excimer laser it is possible to accurately remove retinal tissue without any detectable damage to surrounding cells. Applications of this new technology in retinal surgery are discussed.

  1. Organizational Issues in the Implementation of a Hospital-Based Syringe Exchange Program

    PubMed Central

    Masson, Carmen L.; Sorensen, James L.; Grossman, Nina; Sporer, Karl A.; Des Jarlais, Don C.; Perlman, David C.

    2012-01-01

    Little published information exists to guide health care institutions in establishing syringe exchange program (SEP) services. To address this gap, this article discusses organizational issues encountered in the implementation of a hospital-based SEP in San Francisco, California (USA). Investigators collaborated with a community organization in implementing a county hospital-based SEP. SEP services integrated into a public hospital presented unique challenges directly related to their status as a health care institution. In the course of introducing SEP services into a hospital setting as part of a clinical trial, various ethical, legal, and logistical issues were raised. Based on these experiences, this paper provides guidance on how to integrate an SEP into a traditional health care institution. PMID:20397875

  2. Methyl syringate, a low-molecular-weight phenolic ester, as an activator of the chemosensory ion channel TRPA1.

    PubMed

    Son, Hee Jin; Kim, Min Jung; Park, Jae-Ho; Ishii, Sho; Misaka, Takumi; Rhyu, Mee-Ra

    2012-12-01

    Transient receptor potential channel ankryn 1 (TRPA1) and transient receptor potential channel vanilloid 1 (TRPV1) are members of the TRP superfamily of structurally related, nonselective cation channels and are often coexpressed in sensory neurons. Extracts of the first leaves of Kalopanax pictus Nakai (Araliaceae) have been shown to activate hTRPA1 and hTRPV1. Therefore, the effects of six commercially available chemicals (methyl syringate, coniferyl alcohol, protocatechuic acid, hederacoside C, ?-hederin, and eleutheroside B) found in K. pictus were investigated on cultured cells expressing hTRPA1 and hTRPV1. Of the six compounds, methyl syringate selectively activated hTRPA1 (EC(50) = 507.4 ?M), but not hTRPV1. Although methyl syringate had a higher EC(50) compared with allyl isothiocyanate (EC(50) = 7.4 ?M) and cinnamaldehyde (EC(50) = 22.2 ?M), the present study provides evidence that methyl syringate from K. pictus is a specific and selective activator of hTRPA1. PMID:23263817

  3. Anterior and middle superior alveolar nerve block for anesthesia of maxillary teeth using conventional syringe

    PubMed Central

    Velasco, Ignacio; Soto, Reinaldo

    2012-01-01

    Background: Dental procedures in the maxilla typically require multiple injections and may inadvertently anesthetize facial structures and affect the smile line. To minimize these inconveniences and reduce the number of total injections, a relatively new injection technique has been proposed for maxillary procedures, the anterior and middle superior alveolar (AMSA) nerve block, which achieves pulpal anesthesia from the central incisor to second premolar through palatal approach with a single injection. The purpose of this article is to provide background information on the anterior and middle superior alveolar nerve block and demonstrate its success rates of pulpal anesthesia using the conventional syringe. Materials and Methods: Thirty Caucasian patients (16 men and 14 women) with an average age of 22 years-old, belonging to the School of Dentistry of Los Andes University, were selected. All the patients received an AMSA nerve block on one side of the maxilla using the conventional syringe, 1 ml of lidocaine 2% with epinephrine 1:100.000 was injected to all the patients. Results: The AMSA nerve block obtained a 66% anesthetic success in the second premolar, 40% in the first premolar, 60% in the canine, 23.3% in the lateral incisor, and 16.7% in the central incisor. Conclusions: Because of the unpredictable anesthetic success of the experimental teeth and variable anesthesia duration, the technique is disadvantageous for clinical application as the first choice, counting with other techniques that have greater efficacy in the maxilla. Although, anesthetizing the teeth without numbing the facial muscles may be useful in restorative dentistry. PMID:23559916

  4. A Syringe-Like Love Dart Injects Male Accessory Gland Products in a Tropical Hermaphrodite

    PubMed Central

    Koene, Joris M.; Liew, Thor-Seng; Montagne-Wajer, Kora; Schilthuizen, Menno

    2013-01-01

    Sexual conflict shapes the evolution of many behaviours and processes involved in reproduction. Nearly all evidence supporting this comes from species where the sexes are separated. However, a substantial proportion of animals and most plants are hermaphroditic, and theoretical work predicts that sexual conflict plays an important role even when the sexes are joined within one individual. This seems to have resulted in bizarre mating systems, sophisticated sperm packaging and complex reproductive morphologies. By far the best-known example of such a strategy in hermaphrodites is the shooting of so-called love-darts in land snails. All known love darts carry a gland product on their outside and enter this into the partner’s hemolymph by stabbing. Here, we show that species of the snail genus Everettia possess a syringe-like dart that serves as a real injection needle. Their dart is round in cross-section, contains numerous channels, and has perforations along its side. Histology and electron microscopy show that these holes connect to the channels inside the dart and run all the way up to the elaborate mucus glands that are attached to the dart sac. This is the first report on a love dart that is used as a syringe to directly inject the gland product into the partner’s hemolymph. Although the exact use and function of this dart remains to be demonstrated, this clearly adds to the complexity of the evolution of reproductive strategies in hermaphrodites in general. Moreover, the perforations on the outside of the love dart resemble features of other injection devices, thus uncovering common design and repeated evolution of such features in animals. PMID:23894565

  5. An external evaluation of a peer-run outreach-based syringe exchange in Vancouver, Canada

    PubMed Central

    Hayashi, Kanna; Wood, Evan; Wiebe, Lee; Qi, Jiezhi; Kerr, Thomas

    2010-01-01

    Objective Vancouver, Canada has been the site of an epidemic of human immunodeficiency virus (HIV) among injection drug users (IDU). In response, the Vancouver Area Network of Drug Users (VANDU) initiated a peer-run outreach-based syringe exchange programme (SEP) called the Alley Patrol. We conducted an external evaluation of this programme, using data obtained from the Vancouver Injection Drug Users Study (VIDUS). Methods Using generalised estimating equations (GEE) we examined the prevalence and correlates of use of the SEP among VIDUS participants followed from 1 December 2000 to 30 November 2003. Results Of 854 IDU, 233 (27.3%) participants reported use of the SEP during the study period. In multivariate GEE analyses, service use was positively associated with living in unstable housing (Adjusted Odds Ratio [AOR] = 1.83, 95% Confidence Interval [CI]: 1.39 – 2.40), daily heroin injection (AOR = 1.31, 95% CI: 1.01 – 1.70), daily cocaine injection (AOR = 1.34, 95% CI: 1.03 – 1.73), injecting in public (AOR = 3.07, 95% CI: 2.32 – 4.06), and negatively associated with needle reuse (AOR = 0.65, 95% CI: 0.46 – 0.92). Conclusion The VANDU Alley Patrol SEP succeeded in reaching a group of IDU at heightened risk for adverse health outcomes. Importantly, access to this service was associated with lower levels of needle reuse. This form of peer-based SEP may extend the reach of HIV prevention programmes by contacting IDU traditionally underserved by conventional syringe exchange programmes. PMID:20359877

  6. Methyl syringate: a chemical marker of asphodel (Asphodelus microcarpus Salzm. et Viv.) monofloral honey.

    PubMed

    Tuberoso, Carlo I G; Bifulco, Ersilia; Jerkovi?, Igor; Caboni, Pierluigi; Cabras, Paolo; Floris, Ignazio

    2009-05-13

    During the liquid chromatographic study of the phenolic fraction of monofloral honeys was detected in the asphodel honey ( Asphodelus microcarpus Salzm. et Viv.) chromatogram a distinctive peak not detected in other monofloral honeys such as Arbutus unedo L., Hedysarum coronarium , Eucalyptus spp., and Galactites tomentosa . After thin layer chromatography (TLC) purification and characterization by NMR and LC-MS/MS, the compound was identified as methyl syringate (MSYR) and confirmed against an original standard. Levels of MSYR were measured in honeys of 2005, 2006, and 2007 by HPLC-DAD analysis. Level determination of MSYR was repeated in 2008 for 2006 and 2007 honeys to evaluate chemical stability of this phenolic compound. Levels of MSYR measured 1 year after the sampling did not show significant statistical differences (p < 0.05). The stability of MSYR was also confirmed by 12 asphodel honey samples collected in 2005 that showed amounts of methyl syringate comparable with those found in fresh honey. For the evaluation of MSYR origin, samples of nectars were collected from flowers and the content of MSYR was measured. Levels of MSYR in honeys are originated from the nectar with an average contribution of the nectar to the honey of 80%. Melissopalinological analysis did not allow the attribution of the honey monofloral origin because levels of asphodel pollen were <6% for all analyzed samples. Previously reported levels of MSYR for robinia, rape, chestnut, clover, linden blossom, dandelion, sunflower, thyme, manuka, and fir honeys were <5 mg/kg. For this reason, a minimum level of 122.6 mg/kg for MSYR in asphodel honeys can be considered as a chemical marker and, unlike the melissopalynological analysis, can be used for the origin attribution and to evaluate the percent of asphodel nectar in the honey. PMID:19309074

  7. Summary of OARE flight calibration measurements

    NASA Technical Reports Server (NTRS)

    Blanchard, Robert C.; Nicholson, John Y.

    1995-01-01

    To date, the Orbital Acceleration Research Experiment (OARE) has flown on the shuttle orbiter for five missions; namely, STS-40, STS-50, STS-58, STS-62, and STS-65. The OARE instrument system contains a three-axis accelerometer which can resolve accelerations to the nano-g (10(exp -9) g) level and a full calibration station to permit in situ bias and scale factor calibration measurements. This calibration capability eliminates the large uncertainty encountered with accelerometers flown in the past on the orbiter which use ground-based calibrations to provide absolute acceleration measurements. A detailed flight data report presentation is given for the OARE calibration measurements from all missions, along with an estimate of the calibration errors. The main aim is to collect, process, and present the calibration data in one archival report. These calibration data are the necessary key ingredient to produce the absolute acceleration levels from the OARE acceleration flight data.

  8. Accuracy testing of dose calibrators

    SciTech Connect

    Logan, K.W.; Blondeau, K.L.; Widmer, D.J.; Holmes, R.A.

    1985-12-01

    Current methods for testing a dose calibrator's accuracy use measurements of /sup 60/Co, /sup 137/Cs, /sup 57/Co, and /sup 133/Ba sources but do not directly measure the accuracy of clinical radionuclides such as /sup 99m/Tc, /sup 123/I, /sup 111/In, /sup 67/Ga, or /sup 201/Tl. It is possible that some dose calibrators inaccurately determine the activity of these clinical radiopharmaceuticals. To correct this possible deficiency, the authors have devised a method to test the accuracy of each radionuclide setting on a dose calibrator using a single long-lived calibration source. Differences in emission characteristics of assayed radionuclides are incorporated in the ionization current-to-activity conversion factors (CAF) that are determined experimentally by the manufacturer. The correct functioning of a dose calibrator requires that each CAF be accurately reproduced electronically by the calibrator circuitry and that the measured ionization current be consistent and precise. The results have shown that their procedure tests the total function of the dose calibrator for detecting all radionuclides specified by the manufacturer including the accuracy of the electron representations of the CAF. The procedure is easily implemented for all dose calibrator systems using one of several possible sources available in most laboratories (e.g., /sup 57/Co, /sup 137/Cs, or /sup 133/Ba).

  9. Cross-calibration experiment of JPL AIRSAR and truck-mounted polarimetric scatterometer

    Microsoft Academic Search

    K. Sarabandi; L. E. Pierce; Y. Oh; M. C. Dobson; F. T. Ulaby; A. Freeman; P. Dubois

    1994-01-01

    When point calibration targets are used to calibrate a SAR image, the calibration accuracy is governed by two major factors. The first factor stems from the stringent requirement on the radar cross section (RCS) of the point calibration target. To reduce the effect of radar return from the background, the RCS of a point calibration target must be much larger

  10. Status of Automatic Calibration for Hydrologic Models: Comparison with Multilevel Expert Calibration

    Microsoft Academic Search

    Hoshin Vijai Gupta; Soroosh Sorooshian; Patrice Ogou Yapo

    1999-01-01

    The usefulness of a hydrologic model depends on how well the model is calibrated. Therefore, the calibration procedure must be conducted carefully to maximize the reliability of the model. In general, manual procedures for calibration can be extremely time-consuming and frustrating, and this has been a major factor inhibiting the widespread use of the more sophisticated and complex hydrologic models.

  11. Are major reductions in new HIV infections possible with people who inject drugs? The case for low dead-space syringes in highly affected countries.

    PubMed

    Zule, William A; Cross, Harry E; Stover, John; Pretorius, Carel

    2013-01-01

    Circumstantial evidence from laboratory studies, mathematical models, ecological studies and bio behavioural surveys, suggests that injection-related HIV epidemics may be averted or reversed if people who inject drugs (PWID) switch from using high dead-space to using low dead-space syringes. In laboratory experiments that simulated the injection process and rinsing with water, low dead space syringes retained 1000 times less blood than high dead space syringes. In mathematical models, switching PWID from high dead space to low dead space syringes prevents or reverses injection-related HIV epidemics. No one knows if such an intervention is feasible or what effect it would have on HIV transmission among PWID. Feasibility studies and randomized controlled trials (RCTs) will be needed to answer these questions definitively, but these studies will be very expensive and take years to complete. Rather than waiting for them to be completed, we argue for an approach similar to that used with needle and syringe programs (NSP), which were promoted and implemented before being tested more rigorously. Before implementation, rapid assessments that involve PWID will need to be conducted to ensure buy-in from PWID and other local stakeholders. This commentary summarizes the existing evidence regarding the protective effects of low dead space syringes and estimates potential impacts on HIV transmission; it describes potential barriers to transitioning PWID from high dead space to low dead space needles and syringes; and it presents strategies for overcoming these barriers. PMID:22884539

  12. Detector response and intensity cross-contribution as contributing factors to the observed non-linear calibration curves in mass spectrometric analysis.

    PubMed

    Sie, Meng-Jie; Chen, Bud-Gen; Chang, Chiung Dan; Lin, Chia-Han; Liu, Ray H

    2011-01-21

    It is a common knowledge that detector fatigue causes a calibration curve to deviate from the preferred linear relationship at the higher concentration end. With the adaptation of an isotopically labeled analog of the analyte as the internal standard (IS), cross-contribution (CC) of the intensities monitored for the ions designating the analyte and the IS can also result in a non-linear relationship at both ends. A novel approach developed to assess 'the extent and the effect of [CC]… in quantitative GC-MS analysis' can be extended (a) to examine whether a specific set of CC values is accurate; and (b) to differentiate whether the observed non-linear calibration curve is caused by detector fatigue or the CC phenomenon. Data derived from the exemplar secobarbital (SB)/SB-d(5) system (as di-butyl-derivatives) are used to illustrate this novel approach. Comparing the non-linear nature of calibration data that are empirically observed to that derived from theoretical calculation (with the incorporation of adjustment resulting from the ion CC phenomenon), supports the conclusions that (a) both CC and detector fatigue contribute significantly to the observed non-linear nature of the calibration curve based on ion-pair m/z 207/212; and (b) detector fatigue is the dominating contributor when the calibration curve is based on ion-pair m/z 263/268. PMID:21049098

  13. Langley method of calibrating UV filter radiometers

    NASA Astrophysics Data System (ADS)

    Slusser, James; Gibson, James; Bigelow, David; Kolinski, Donald; Disterhoft, Patrick; Lantz, Kathleen; Beaubien, Arthur

    2000-02-01

    The Langley method of calibrating UV multifilter shadow band radiometers (UV-MFRSR) is explored in this paper. This method has several advantages over the traditional standard lamp calibrations: the Sun is a free, universally available, and very constant source, and nearly continual automated field calibrations can be made. Although 20 or so Langley events are required for an accurate calibration, the radiometer remains in the field during calibration. Difficulties arise as a result of changing ozone optical depth during the Langley event and the breakdown of the Beer-Lambert law over the finite filter band pass since optical depth changes rapidly with wavelength. The Langley calibration of the radiometers depends critically upon the spectral characterization of each channel and on the wavelength and absolute calibration of the extraterrestrial spectrum used. Results of Langley calibrations for two UV-MFRSRs at Mauna Loa, Hawaii were compared to calibrations using two National Institute of Standards and Technology (NIST) traceable lamps. The objectives of this study were to compare Langley calibration factors with those from standard lamps and to compare field-of-view effects. The two radiometers were run simultaneously: one on a Sun tracker and the other in the conventional shadow-band configuration. Both radiometers were calibrated with two secondary 1000 W lamp, and later, the spectral response functions of the channels were measured. The ratio of Langley to lamp calibration factors for the seven channels from 300 nm to 368 nm using the shadow-band configuration ranged from 0.988 to 1.070. The estimated uncertainty in accuracy of the Langley calibrations ranged from ±3.8% at 300 nm to ±2.1% at 368 nm. For all channels calibrated with Central Ultraviolet Calibration Facility (CUCF) lamps the estimated uncertainty was ±2.5% for all channels.

  14. Hyaluronic acid filler and botulinum Neurotoxin delivered simultaneously in the same syringe for effective and convenient combination aesthetic rejuvenation therapy.

    PubMed

    Kenner, Julie R

    2010-09-01

    Facial aesthetics and rejuvenation techniques have been evolving, with the most commonly applied techniques being the use of hyaluronic acid fillers and botulinum neurotoxins. Because of complementary actions, it is common for both products to be used in the same anatomical sites to optimize outcomes, either administered consecutively at one visit or at two separate visits. The author shows for the first time that hyaluronic acid (HA) and botulinum neurotoxin (BNT) can be delivered in combination in the same syringe--at the same time--to rejuvenate the upper face. Not only does concomitant administration result in excellent clinical outcome, without apparently compromising the attributes of either product alone, but this technique enhances the patient experience by allowing the use of small-gauge needles and inherently decreasing, by half or more, the number of needle sticks incurred. Larger studies are underway to study optimal techniques for administering HA and BNT combined in a single syringe. PMID:20865847

  15. Functional evaluation and characterization of a newly developed silicone oil-free prefillable syringe system.

    PubMed

    Yoshino, Keisuke; Nakamura, Koji; Yamashita, Arisa; Abe, Yoshihiko; Iwasaki, Kazuhiro; Kanazawa, Yukie; Funatsu, Kaori; Yoshimoto, Tsuyoshi; Suzuki, Shigeru

    2014-05-01

    The functionality of a newly developed silicone oil-free (SOF) syringe system, of which the plunger stopper is coated by a novel coating technology (i-coating™), was assessed. By scanning electron microscopy observations and other analysis, it was confirmed that the plunger stopper surface was uniformly covered with the designed chemical composition. A microflow imaging analysis showed that the SOF system drastically reduced both silicone oil (SO) doplets and oil-induced aggregations in a model protein formulation, whereas a large number of subvisible particles and protein aggregations were formed when a SO system was used. Satisfactory container closure integrity (CCI) was confirmed by means of dye and microorganism penetration studies. Furthermore, no significant difference between the break loose and gliding forces was observed in the former, and stability studies revealed that the SOF system could perfectly show the aging independence in break loose force observed in the SO system. The results suggest that the introduced novel SOF system has a great potential and represents an alternative that can achieve very low subvisible particles, secure CCI, and the absence of a break loose force. In particular, no risk of SO-induced aggregation can bring additional value in the highly sensitive biotech drug market. PMID:24643749

  16. Syringe filtration methods for examining dissolved and colloidal trace element distributions in remote field locations

    NASA Technical Reports Server (NTRS)

    Shiller, Alan M.

    2003-01-01

    It is well-established that sampling and sample processing can easily introduce contamination into dissolved trace element samples if precautions are not taken. However, work in remote locations sometimes precludes bringing bulky clean lab equipment into the field and likewise may make timely transport of samples to the lab for processing impossible. Straightforward syringe filtration methods are described here for collecting small quantities (15 mL) of 0.45- and 0.02-microm filtered river water in an uncontaminated manner. These filtration methods take advantage of recent advances in analytical capabilities that require only small amounts of waterfor analysis of a suite of dissolved trace elements. Filter clogging and solute rejection artifacts appear to be minimal, although some adsorption of metals and organics does affect the first approximately 10 mL of water passing through the filters. Overall the methods are clean, easy to use, and provide reproducible representations of the dissolved and colloidal fractions of trace elements in river waters. Furthermore, sample processing materials can be prepared well in advance in a clean lab and transported cleanly and compactly to the field. Application of these methods is illustrated with data from remote locations in the Rocky Mountains and along the Yukon River. Evidence from field flow fractionation suggests that the 0.02-microm filters may provide a practical cutoff to distinguish metals associated with small inorganic and organic complexes from those associated with silicate and oxide colloids.

  17. Functional Evaluation and Characterization of a Newly Developed Silicone Oil-Free Prefillable Syringe System

    PubMed Central

    Yoshino, Keisuke; Nakamura, Koji; Yamashita, Arisa; Abe, Yoshihiko; Iwasaki, Kazuhiro; Kanazawa, Yukie; Funatsu, Kaori; Yoshimoto, Tsuyoshi; Suzuki, Shigeru

    2014-01-01

    The functionality of a newly developed silicone oil-free (SOF) syringe system, of which the plunger stopper is coated by a novel coating technology (i-coating™), was assessed. By scanning electron microscopy observations and other analysis, it was confirmed that the plunger stopper surface was uniformly covered with the designed chemical composition. A microflow imaging analysis showed that the SOF system drastically reduced both silicone oil (SO) doplets and oil-induced aggregations in a model protein formulation, whereas a large number of subvisible particles and protein aggregations were formed when a SO system was used. Satisfactory container closure integrity (CCI) was confirmed by means of dye and microorganism penetration studies. Furthermore, no significant difference between the break loose and gliding forces was observed in the former, and stability studies revealed that the SOF system could perfectly show the aging independence in break loose force observed in the SO system. The results suggest that the introduced novel SOF system has a great potential and represents an alternative that can achieve very low subvisible particles, secure CCI, and the absence of a break loose force. In particular, no risk of SO-induced aggregation can bring additional value in the highly sensitive biotech drug market. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:1520–1528, 2014 PMID:24643749

  18. Phthalate analysis by gas chromatography-mass spectrometry: blank problems related to the syringe needle.

    PubMed

    Marega, Milena; Grob, Konrad; Moret, Sabrina; Conte, Lanfranco

    2013-01-18

    For the analysis of the most commonly encountered phthalates by gas chromatography-mass spectrometry (GC-MS), absorption of phthalates from the laboratory air on the outer wall of the syringe needle is shown to be an important contribution to the blank problems. It was investigated for programmed temperature vapourizing (PTV) injection. Cleaning of the needle in automated injection is of modest efficiency, since the needle cannot be immersed deeply enough into the wash vial. Two approaches were studied to minimize the transfer into the column: (i) cleaning of the needle in the injector prior to splitless injection by inserting the needle in split mode while the precolumn is backflushed, which presupposes a high injector temperature to be efficient; (ii) injection under conditions minimizing thermal desorption from the needle wall, i.e. fast injection at low injector temperature (e.g. 40 °C). Both approaches resulted in blank levels of around 0.1 pg for diisobutyl phthalate (DIBP) and dibutyl phthalate (DBP), and of around 1 pg for di(2-ethylhexyl) phthalate (DEHP). They could be useful tools in existing or future methods for the analysis of phthalates or other compounds causing blank problems through contamination of the laboratory air. PMID:23265992

  19. Direct Evidence of Egestion and Salivation of Xylella fastidiosa Suggests Sharpshooters Can Be "Flying Syringes".

    PubMed

    Backus, Elaine A; Shugart, Holly J; Rogers, Elizabeth E; Morgan, J Kent; Shatters, Robert

    2015-05-01

    Xylella fastidiosa is unique among insect-transmitted plant pathogens because it is propagative but noncirculative, adhering to and multiplying on the cuticular lining of the anterior foregut. Any inoculation mechanism for X. fastidiosa must explain how bacterial cells exit the vector's stylets via the food canal and directly enter the plant. A combined egestion-salivation mechanism has been proposed to explain these unique features. Egestion is the putative outward flow of fluid from the foregut via hypothesized bidirectional pumping of the cibarium. The present study traced green fluorescent protein-expressing X. fastidiosa or fluorescent nanoparticles acquired from artificial diets by glassy-winged sharpshooters, Homalodisca vitripennis, as they were egested into simultaneously secreted saliva. X. fastidiosa or nanoparticles were shown to mix with gelling saliva to form fluorescent deposits and salivary sheaths on artificial diets, providing the first direct, conclusive evidence of egestion by any hemipteran insect. Therefore, the present results strongly support an egestion-salivation mechanism of X. fastidiosa inoculation. Results also support that a column of fluid is transiently held in the foregut without being swallowed. Evidence also supports (but does not definitively prove) that bacteria were suspended in the column of fluid during the vector's transit from diet to diet, and were egested with the held fluid. Thus, we hypothesize that sharpshooters could be true "flying syringes," especially when inoculation occurs very soon after uptake of bacteria, suggesting the new paradigm of a nonpersistent X. fastidiosa transmission mechanism. PMID:26020829

  20. Single crystal growth of InBi 1- xSe x by syringe pulling method

    NASA Astrophysics Data System (ADS)

    Shah, Dimple; Pandya, Girish; Vyas, Sandip; Jani, Maunik; Jariwala, Bhakti

    2010-04-01

    In recent years, III-V compounds have received some attention as potential candidates for infrared application in the 8-12 ?m range. Single crystal of InBi:Se belonging to the same system has been grown by Syringe pulling method. The charge was allowed to cool freely to room temperature, which took about 10 min. The stainless steel needle serves as heat sink and site of nucleation. Crystals were cleaved along the cleavage plane (0 0 1) parallel to the vertical growth axis. Growth features were studied on the surface of crystals. XRD technique has been used for testing the presence of constituent element of InBi:Se single crystal. Standard test for a new dislocation etchant has been carried out successfully and results are reported. The optical absorption was measured in the wave number range 500-4000 cm -1. The bandgap has been evaluated from these data and studied as a function of concentration. The increase in concentration has been also found to affect their hardness.

  1. A laser syringe aimed at delivering drug into the outer layer of human skin

    NASA Astrophysics Data System (ADS)

    Yoh, Jack J.; Jang, Hun-jae; Park, Mi-ae; Han, Tae-hee; Hah, Jung-moo

    2012-07-01

    A desire to eliminate hypodermic needle in transdermal drug delivery may now be realized. Imaging of the skin after injection of fluorescent probe and biotin via the bio-ballistic technique revealed the epidermal and dermal layers which were stained well below 60 ?m underneath the abdominal skin of the guinea-pig. An extensive network of cells are shown in the deeper layer of the stained dermis as the distributed fluorescein isothiocyanate (FITC) dose is administered by repeated injection via the laser-based microjet. Here, we show our method of laser-based microjet drug delivery is capable of breaching guinea-pig's skin tissue and then delivering controlled dose of drug to the targeted region between 10 to 400 ?m underneath the outermost layer of the skin. While minimizing pain and tissue damage by reducing the injection volume to ˜100 nl per pulse and the microjet diameter of half the conventional syringe needle in 100 ?m, the optimally controlled delivery of liquid drug by the irradiated laser pulse is shown possible.

  2. False selection of syringe-brand compatibility and the method of correction during target-controlled infusion of propofol

    PubMed Central

    Chae, Yun-Jeong; Kim, Jong-Yeop; Kim, Do-Won; Moon, Bong-Ki

    2013-01-01

    Background We evaluated volumetric differences of syringe brand compatibilities, and investigated the impact of false brand settings on target-controlled infusion (TCI) and their methods of correction. Methods Gravimetric measurement of 10 ml bolus infusions was performed using BD Plastipak (BDP) and Terumo compatible syringes, while setting to 7 different kinds of brand compatibilities (BDP, Sherwood Monoject, BD Perfusion, Braun Perfusor, Braun Omnifix, Fresenius Injectomat, and Terumo). To investigate the performance of TCI using BDP with a false setting to Terumo (BDPTERUMO) and Terumo to BDP (TERUMOBDP), 24 TCI targeting 4.0 µg/ml of effect-site concentration (Ceff) of propofol were performed. Subsequently, another 24 TCI were evaluated for simple corrections of false settings at 30 min. We also investigated 24 TCI using active corrections (fill-up for BDPTERUMO, evacuation for TERUMOBDP) based on the pharmacokinetics of propofol. The Ceff at 30 min of TCI and time to normalize to ± 5% of target concentration (T±5%target) were compared. Results The Ceff of BDPTERUMO showed negative bias and 17.2% inaccuracy, and the Ceff of TERUMOBDP showed positive bias and 19.5% inaccuracy. The Ceff at 30 min showed no difference between the methods of correction in BDPTERUMO or TERUMOBDP. The T±5%target in both the active corrections was significantly shorter than that of each simple corrections (P < 0.001). Conclusions False brand setting of syringe proportionally maintained different predicted concentrations as much as the volumetric differences of syringe brand. Based on the results, it is proposed that correction methods based on pharmacokinetics could effectively normalize the differences, without giving up the wrong TCI. PMID:23560192

  3. Absolute calibration in vivo measurement systems

    SciTech Connect

    Kruchten, D.A.; Hickman, D.P.

    1991-02-01

    Lawrence Livermore National Laboratory (LLNL) is currently investigating a new method for obtaining absolute calibration factors for radiation measurement systems used to measure internally deposited radionuclides in vivo. Absolute calibration of in vivo measurement systems will eliminate the need to generate a series of human surrogate structures (i.e., phantoms) for calibrating in vivo measurement systems. The absolute calibration of in vivo measurement systems utilizes magnetic resonance imaging (MRI) to define physiological structure, size, and composition. The MRI image provides a digitized representation of the physiological structure, which allows for any mathematical distribution of radionuclides within the body. Using Monte Carlo transport codes, the emission spectrum from the body is predicted. The in vivo measurement equipment is calibrated using the Monte Carlo code and adjusting for the intrinsic properties of the detection system. The calibration factors are verified using measurements of existing phantoms and previously obtained measurements of human volunteers. 8 refs.

  4. Place of Residence Moderates the Relationship Between Emotional Closeness and Syringe Sharing Among Injection Drug Using Clients of Sex Workers in the US-Mexico Border Region.

    PubMed

    Wagner, Karla D; Pitpitan, Eileen V; Valente, Thomas W; Strathdee, Steffanie A; Rusch, Melanie; Magis-Rodriguez, Carlos; Chavarin, Claudia V; Patterson, Thomas L

    2015-06-01

    Injection drug-using men from the US and Mexico who purchase sex in Tijuana, Mexico are at risk for transmitting HIV to their contacts in both countries via syringe sharing. We used social network methods to understand whether place of residence (US vs. Mexico) moderated the effect of emotional closeness on syringe sharing. We interviewed 199 drug-using men who reported paying/trading for sex in Tijuana, Mexico using an epidemiological and social network survey and collected samples for HIV/STI testing. Seventy-two men reported using injection drugs with 272 network contacts. Emotional closeness was strongly associated with syringe sharing in relationship where the partner lives in the US, while the relationship between emotional closeness and syringe sharing was considerably less strong in dyads where the partner lives in Mexico. Efforts to reduce HIV risk behaviors in emotionally close relationships are needed, and could benefit from tailoring to the environmental context of the relationship. PMID:25613593

  5. Cloning and Sequencing of the Sphingomonas (Pseudomonas) paucimobilis Gene Essential for the O Demethylation of Vanillate and Syringate

    PubMed Central

    Nishikawa, Seiji; Sonoki, Tomonori; Kasahara, Tatsuhide; Obi, Takahiro; Kubota, Shoko; Kawai, Shinya; Morohoshi, Noriyuki; Katayama, Yoshihiro

    1998-01-01

    Sphingomonas (Pseudomonas) paucimobilis SYK-6 is able to grow on 5,5?-dehydrodivanillic acid (DDVA), syringate, vanillate, and other dimeric model compounds of lignin as a sole carbon source. Nitrosoguanidine mutagenesis of S. paucimobilis SYK-6 was performed, and two mutants with altered DDVA degradation pathways were isolated. The mutant strain NT-1 could not degrade DDVA, but could degrade syringate, vanillate, and 2,2?,3?-trihydroxy-3-methoxy-5,5?-dicarboxybiphenyl (OH-DDVA). Strain DC-49 could slowly assimilate DDVA, but could degrade neither vanillate nor syringate, although it could degrade protocatechuate and 3-O-methylgallate. A complementing DNA fragment of strain DC-49 was isolated from the cosmid library of strain SYK-6. The minimum DNA fragment complementing DC-49 was determined to be the 1.8-kbp insert of pKEX2.0. Sequencing analysis showed an open reading frame of 1,671 bp in this fragment, and a similarity search indicated that the deduced amino acid sequence of this open reading frame had significant similarity (60%) to the formyltetrahydrofolate synthetase of Clostridium thermoaceticum. PMID:9501423

  6. A new syringe pump apparatus for the retrieval and temporal analysis of helium in groundwaters and geothermal fluids

    USGS Publications Warehouse

    Barry, P.H.; Hilton, David R.; Tryon, M.D.; Brown, K.M.; Kulongoski, J.T.

    2009-01-01

    [1] We present details of a newly designed syringe pump apparatus for the retrieval and temporal analysis of helium (SPARTAH). The device is composed of a commercially available syringe pump connected to coils of Cu tubing, which interface the syringe and the groundwater or geothermal wellhead. Through test deployments at geothermal wells in Iceland and California, we show that well fluids are drawn smoothly, accurately, and continuously into the Cu tubing and can be time-stamped through user-determined operating parameters. In the laboratory, the tubing is sectioned to reveal helium (He) characteristics of the fluids at times and for durations of interest. The device is capable of prolonged deployments, up to 6 months or more, with minimal maintenance. It can be used to produce detailed time series records of He, or any other geochemical parameter, in groundwaters and geothermal fluids. SPARTAH has application in monitoring projects assessing the relationship between external transient events (e.g., earthquakes) and geochemical signals in aqueous fluids. ?? 2009 by the American Geophysical Union.

  7. Summary of OARE flight calibration measurements

    Microsoft Academic Search

    Robert C. Blanchard; John Y. Nicholson

    1995-01-01

    To date, the Orbital Acceleration Research Experiment (OARE) has flown on the shuttle orbiter for five missions; namely, STS-40, STS-50, STS-58, STS-62, and STS-65. The OARE instrument system contains a three-axis accelerometer which can resolve accelerations to the nano-g (10(exp -9) g) level and a full calibration station to permit in situ bias and scale factor calibration measurements. This calibration

  8. The effect of pH on the transformation of syringic and vanillic acids by the laccases of Rhizoctonia praticola and Trametes versicolor

    Microsoft Academic Search

    A. Leonowicz; R. U. Edgehill; J.-M. Bollag

    1984-01-01

    Laccases (benzenediol: oxygen oxidoreductases, EC 1.10.3.2) from Rhizoctonia praticola and Trametes versicolor formed different products from syringic and vanillic acids at different pH values, but both enzymes generated the same chemicals at a particular pH. The products were separated by thin-layer and high-performance liquid chromatography. Four compounds were determined from syringic acid (m\\/z 168, 334, 350 and 486) at pH

  9. Randomized, community-based pharmacy intervention to expand services beyond sale of sterile syringes to injection drug users in pharmacies in New York City.

    PubMed

    Crawford, Natalie D; Amesty, Silvia; Rivera, Alexis V; Harripersaud, Katherine; Turner, Alezandria; Fuller, Crystal M

    2013-09-01

    Structural interventions may help reduce racial/ethnic disparities in HIV. In 2009 to 2011, we randomized pharmacies participating in a nonprescription syringe access program in minority communities to intervention (pharmacy enrolled and delivered HIV risk reduction information to injection drug users [IDUs]), primary control (pharmacy only enrolled IDUs), and secondary control (pharmacy did not engage IDUs). Intervention pharmacy staff reported more support for syringe sales than did control staff. An expanded pharmacy role in HIV risk reduction may be helpful. PMID:23865644

  10. New York City Injection Drug Users’ Memories of Syringe-Sharing Patterns and Changes During the Peak of the HIV\\/AIDS Epidemic

    Microsoft Academic Search

    Russell Rockwell; Herman Joseph; Samuel R. Friedman

    2006-01-01

    In this oral history, 23 injection drug users (IDUs) were interviewed about the mid-1970s to mid-1980s when they could not legally purchase or possess syringes, and the threat of AIDS began to loom large. Several themes emerged, including: abrupt changes in syringe-sharing patterns; the effects of illnesses or deaths of others on their understanding of AIDS; and, racial\\/ethnic differences in

  11. Calibration of the radionuclide logging system germanium detector

    SciTech Connect

    Randall, R.R.

    1994-12-05

    High resolution passive gamma-ray logging, high resolution gamma-ray-emitting nuclides in areas surrounding underground waste disposal facilities on the US Department of Energy`s Hanford Site. Gamma-ray source concentrations are derived from log data by calculations that employ the calibration factors and correction functions described in this report. Calibration data were collected with a Radionuclide Logging System. Analyses of the calibration data established: (1) calibration factors for potassium, uranium, and thorium, and (2) a calibration function that permits assessments of cesium-137, cobalt-60, and other artificial nuclides not represented in the calibration models.

  12. Evaluation of expanded uncertainties in luminous intensity and illuminance calibrations

    SciTech Connect

    Sametoglu, Ferhat

    2008-11-01

    Detector-based calibrating methods and expressions for calculation of photometric uncertainties related to uncertainties in the calibrations of luminous intensity of a light source, illuminance responsivity of a photometer head, and calibration factors of an illuminance meter are discussed. These methods permit luminous intensity calibrations of incandescent light sources, luminous responsivity calibrations of photometer heads, and calibration factors of illuminance meters to be carried out with relative expanded uncertainties (with a level of confidence of 95.45%) of 0.4%, 0.4%, and 0.6%, respectively.

  13. Evaluation of a new syringe presentation of reduced-antigen content diphtheria, tetanus, and acellular pertussis vaccine in healthy adolescents - A single blind randomized trial.

    PubMed

    Pavia-Ruz, Noris; Abarca, Katia; Lepetic, Alejandro; Cervantes-Apolinar, Maria Yolanda; Hardt, Karin; Jayadeva, Girish; Kuriyakose, Sherine; Han, Htay Htay; de la O, Manuel

    2015-07-01

    Reduced-antigen-content diphtheria-tetanus-acellular pertussis (dTpa) vaccine, Boostrix™, is indicated for booster vaccination of children, adolescents and adults. The original prefilled disposable dTpa syringe presentation was recently replaced by another prefilled-syringe presentation with latex-free tip-caps and plunger-stoppers. 671 healthy adolescents aged 10-15 years who had previously received 5 or 6 previous DT(P)/dT(pa) vaccine doses, were randomized (1:1) to receive dTpa booster, injected using the new (dTpa-new) or previous syringe (dTpa-previous) presentations. Immunogenicity was assessed before and 1-month post-booster vaccination; safety/reactogenicity were assessed during 31-days post-vaccination. Non-inferiority of dTpa-new versus dTpa-previous was demonstrated for all antigens (ULs 95% CIs for GMC ratios ranged between 1.03-1.13). 1-month post-booster, immune responses were in similar ranges for all antigens with both syringe presentations. dTpa delivered using either syringe presentation was well-tolerated. These clinical results complement the technical data and support the use of the new syringe presentation to deliver the dTpa vaccine. PMID:26075317

  14. The efficiency calibration and development of environmental correction factors for an in situ high-resolution gamma spectroscopy well logging system

    SciTech Connect

    Giles, J.R.

    1996-05-01

    A Gamma Spectroscopy Logging System (GSLS) has been developed to study sub-surface radionuclide contamination. Absolute efficiency calibration of the GSLS was performed using simple cylindrical borehole geometry. The calibration source incorporated naturally occurring radioactive material (NORM) that emitted photons ranging from 186-keV to 2,614-keV. More complex borehole geometries were modeled using commercially available shielding software. A linear relationship was found between increasing source thickness and relative photon fluence rates at the detector. Examination of varying porosity and moisture content showed that as porosity increases, relative photon fluence rates increase linearly for all energies. Attenuation effects due to iron, water, PVC, and concrete cylindrical shields were found to agree with previous studies. Regression analyses produced energy-dependent equations for efficiency corrections applicable to spectral gamma-ray well logs collected under non-standard borehole conditions.

  15. Factoring

    NSDL National Science Digital Library

    Mr Clark

    2012-10-31

    Test your factoring skills Factors and Multiples Jeopardy How much do you know about factoring and multiples? Play Jeopardy and find out! Prime Factoring Turkey Shoot Blast these turkeys using your factoring skills. Help the Professor Super save the planet by "cooking" the Giant Frozen Turkeys of Destruction. Math Lines 12 X-Factor Shoot the ball at the other factors to get a product of 12. You can also ...

  16. A novel approach for absolute radar calibration

    NASA Astrophysics Data System (ADS)

    Merker, C.; Peters, G.; Clemens, M.; Lengfeld, K.; Ament, F.

    2015-02-01

    The theoretical framework of a novel approach for absolute radar calibration is presented and its potential analysed by means of synthetic data to lay out a solid basis for future practical application. The method presents the advantage of an absolute calibration with respect to the directly measured reflectivity, without needing a previously calibrated reference device. It requires a setup comprising three radars: two devices oriented towards each other, measuring reflectivity along the same horizontal beam and operating within a strongly attenuated frequency range (e.g. K or X band) and one vertical reflectivity and drop size distribution (DSD) profiler below this connecting line, which is to be calibrated. The absolute determination of the calibration factor is based on attenuation estimates. Using synthetic, smooth and geometrically idealised data calibration is found to perform best using homogeneous precipitation events with rain rates high enough to ensure a distinct attenuation signal (approx. 30 dBZ). Furthermore, the choice of the interval width (in measuring range gates) around the vertically pointing radar, needed for attenuation estimation, is found to have an impact on the calibration results. Further analysis is done by means of synthetic data with realistic, inhomogeneous precipitation fields taken from measurements. A calibration factor is calculated for each considered case using the presented method. Based on the distribution of the calculated calibration factors, the most probable value is determined by estimating the mode of a fitted shifted logarithmic normal distribution function. After filtering the data set with respect to rain rate and inhomogeneity and choosing an appropriate length of the considered attenuation path, the estimated uncertainty of the calibration factor is in the order of 1%. Considering stability and accuracy of the method, an interval of 8 range gates on both sides of the vertically pointing radar is most appropriate for calibration.

  17. Reduction of Systematic Errors in Diagnostic Receivers Through the Use of Balanced Dicke-Switching and Y-Factor Noise Calibrations

    SciTech Connect

    John Musson, Trent Allison, Roger Flood, Jianxun Yan

    2009-05-01

    Receivers designed for diagnostic applications range from those having moderate sensitivity to those possessing large dynamic range. Digital receivers have a dynamic range which are a function of the number of bits represented by the ADC and subsequent processing. If some of this range is sacrificed for extreme sensitivity, noise power can then be used to perform two-point load calibrations. Since load temperatures can be precisely determined, the receiver can be quickly and accurately characterized; minute changes in system gain can then be detected, and systematic errors corrected. In addition, using receiver pairs in a balanced approach to measuring X+, X-, Y+, Y-, reduces systematic offset errors from non-identical system gains, and changes in system performance. This paper describes and demonstrates a balanced BPM-style diagnostic receiver, employing Dicke-switching to establish and maintain real-time system calibration. Benefits of such a receiver include wide bandwidth, solid absolute accuracy, improved position accuracy, and phase-sensitive measurements. System description, static and dynamic modelling, and measurement data are presented.

  18. Testing calibration routines for LISFLOOD, a distributed hydrological model

    Microsoft Academic Search

    B. Pannemans

    2009-01-01

    Traditionally hydrological models are considered as difficult to calibrate: their highly non-linearity results in rugged and rough response surfaces were calibration algorithms easily get stuck in local minima. For the calibration of distributed hydrological models two extra factors play an important role: on the one hand they are often costly on computation, thus restricting the feasible number of model runs;

  19. NIMBY localism and national inequitable exclusion alliances: The case of syringe exchange programs in the United States

    PubMed Central

    Tempalski, Barbara; Friedman, Risa; Keem, Marie; Cooper, Hannah; Friedman, Samuel R.

    2007-01-01

    Syringe exchange programs (SEPs) aim to reduce the harm associated with injection drug use (IDU). Although they have been accepted as critical components of HIV prevention in many parts of the world, they are often unwelcome and difficult to set up and maintain, even in communities hardest hit by IDU-related HIV transmission. This research examines socio-cultural and political processes that shape community and institutional resistance toward establishing and maintaining SEPs. These processes are configured and reinforced through the socio-spatial stigmatizing of IDUs, and legal and public policy against SEPs. Overarching themes the paper considers are: (1) institutional and/or political opposition based on (a) political and law enforcement issues associated with state drug paraphernalia laws and local syringe laws; (b) harassment of drug users and resistance to services for drug users by local politicians and police; and (c) state and local government (in)action or opposition; and (2) the stigmatization of drug users and location of SEPs in local neighborhoods and business districts. Rather than be explained by “not in my back yard” localism, this pattern seems best conceptualized as an “inequitable exclusion alliance” (IEA) that institutionalizes national and local stigmatizing of drug users and other vulnerable populations. PMID:18978931

  20. Effect of liposomes on rheological and syringeability properties of hyaluronic acid hydrogels intended for local injection of drugs.

    PubMed

    El Kechai, Naila; Bochot, Amélie; Huang, Nicolas; Nguyen, Yann; Ferrary, Evelyne; Agnely, Florence

    2015-06-20

    The aim of this work was to thoroughly study the effect of liposomes on the rheological and the syringeability properties of hyaluronic acid (HA) hydrogels intended for the local administration of drugs by injection. Whatever the characteristics of the liposomes added (neutral, positively or negatively charged, with a corona of polyethylene glycol chains, size), the viscosity and the elasticity of HA gels increased in a lipid concentration-dependent manner. Indeed, liposomes strengthened the network formed by HA chains due to their interactions with this polymer. The nature and the resulting effects of these interactions depended on liposome composition and concentration. The highest viscosity and elasticity were observed with liposomes covered by polyethylene glycol chains while neutral liposomes displayed the lowest effect. Despite their high viscosity at rest, all the formulations remained easily injectable through needles commonly used for local injections thanks to the shear-thinning behavior of HA gels. The present study demonstrates that rheological and syringeability tests are both necessary to elucidate the behavior of such systems during and post injection. In conclusion, HA liposomal gels appear to be a promising and versatile formulation platform for a wide range of applications in local drug delivery when an injection is required. PMID:25882015

  1. Parabens determination in cosmetic and personal care products exploiting a multi-syringe chromatographic (MSC) system and chemiluminescent detection.

    PubMed

    Rodas, Melisa; Portugal, Lindomar A; Avivar, Jessica; Estela, José Manuel; Cerdà, Víctor

    2015-10-01

    Parabens are widely used in dairy products, such as in cosmetics and personal care products. Thus, in this work a multi-syringe chromatographic (MSC) system is proposed for the first time for the determination of four parabens: methylparaben (MP), ethylparaben (EP), propylparaben (PP) and butylparaben (BP) in cosmetics and personal care products, as a simpler, practical, and low cost alternative to HPLC methods. Separation was achieved using a 5mm-long precolumn of reversed phase C18 and multi-isocratic separation, i.e. using two consecutive mobile phases, 12:88 acetonitrile:water and 28:72 acetonitrile:water. The use of a multi-syringe buret allowed the easy implementation of chemiluminescent (CL) detection after separation. The chemiluminescent detection is based on the reduction of Ce(IV) by p-hydroxybenzoic acid, product of the acid hydrolysis of parabens, to excite rhodamine 6G (Rho 6G) and measure the resulting light emission. Multivariate designs combined with the concepts of multiple response treatments and desirability functions have been employed to simultaneously optimize and evaluate the responses. The optimized method has proved to be sensitive and precise, obtaining limits of detection between 20 and 40µgL(-1) and RSD <4.9% in all cases. The method was satisfactorily applied to cosmetics and personal care products, obtaining no significant differences at a confidence level of 95% comparing with the HPLC reference method. PMID:26078157

  2. Determination of volatile organic acids in tobacco by single-drop microextraction with in-syringe derivatization followed by GC-MS.

    PubMed

    Sha, Yunfei; Meng, Jiaoran; Zhang, Yichun; Deng, Chunhui; Wu, Da

    2010-02-01

    In this work, the novel technique based on headspace single-drop microextraction with in-syringe derivatization followed by GC-MS was established to determine the volatile organic acids in tobacco. The parameters for headspace single-drop microextraction and in-syringe derivatization were optimized, including extraction time, and volume of derivatization reagent and in-syringe derivatization time. The method validations including linearity, precision, recovery and LOD were also studied. The obtained results illustrated that the optimized technique was easy, highly efficient and sensitive. Finally, the proposed method was successfully applied to the analyses of volatile organic acids in tobacco samples with seven different brands. It was further demonstrated that the present technique developed in this study does offer a simple and fast approach to determine volatile organic acids in tobacco. PMID:20039308

  3. Distributed radio interferometric calibration

    NASA Astrophysics Data System (ADS)

    Yatawatta, Sarod

    2015-06-01

    Increasing data volumes delivered by a new generation of radio interferometers require computationally efficient and robust calibration algorithms. In this paper, we propose distributed calibration as a way of improving both computational cost as well as robustness in calibration. We exploit the data parallelism across frequency that is inherent in radio astronomical observations that are recorded as multiple channels at different frequencies. Moreover, we also exploit the smoothness of the variation of calibration parameters across frequency. Data parallelism enables us to distribute the computing load across a network of compute agents. Smoothness in frequency enables us to reformulate calibration as a consensus optimization problem. With this formulation, we enable flow of information between compute agents calibrating data at different frequencies, without actually passing the data, and thereby improving robustness. We present simulation results to show the feasibility as well as the advantages of distributed calibration as opposed to conventional calibration.

  4. Calibrated Peer Review

    NSDL National Science Digital Library

    What is Calibrated Peer ReviewTM? Calibrated Peer ReviewTM (CPR) (more info) is a web-based writing and peer review tool free to instructors and their classes. Students write short essays on a given topic following ...

  5. Automated Camera Calibration

    NASA Technical Reports Server (NTRS)

    Chen, Siqi; Cheng, Yang; Willson, Reg

    2006-01-01

    Automated Camera Calibration (ACAL) is a computer program that automates the generation of calibration data for camera models used in machine vision systems. Machine vision camera models describe the mapping between points in three-dimensional (3D) space in front of the camera and the corresponding points in two-dimensional (2D) space in the camera s image. Calibrating a camera model requires a set of calibration data containing known 3D-to-2D point correspondences for the given camera system. Generating calibration data typically involves taking images of a calibration target where the 3D locations of the target s fiducial marks are known, and then measuring the 2D locations of the fiducial marks in the images. ACAL automates the analysis of calibration target images and greatly speeds the overall calibration process.

  6. Assessment of MODIS Reflected Solar Calibration Uncertainty

    NASA Technical Reports Server (NTRS)

    Xiong, Xiaoxiong; Sun, Junqiang; Butler, James

    2011-01-01

    Determination of the calibration accuracy and traceability of a remote sensing instrument is a driving issue in the use of satellite data for calibration inter-comparisons and studying climate change. The Terra and Aqua MODerate Resolution Imaging Spectroradiometer (MODIS) instruments have successfully operated for more than 11 and 9 years, respectively. Twenty of the thirty six MODIS spectral bands are in the reflected solar region with center wavelengths ranging from 0.41 to 2.2 microns. MODIS reflective solar band (RSB) on-orbit calibration is reflectance based through the use of an on-board solar diffuser (SO). The calibration uncertainty requirements are +/-2.0% for the RSB reflectance factors at sensor specified typical scene reflectances or radiances. The SO bi-directional reflectance factor (BRF) was characterized pre-launch and its on-orbit changes are tracked by an on-board solar diffuser stability monitor (SDSM). This paper provides an assessment of MODIS RSB on-orbit calibration traceability and uncertainty for its Level 1B (L1B) reflectance factors. It examines in details each of the uncertainty contributors, including those from pre-launch measurements as well as on-orbit observations. Common challenging issues and differences due to individual sensors' specific characteristics and on-orbit performance are also discussed in this paper. Guidance and recommendations are presented, based on lessons from MODIS RSB calibration uncertainty assessment, for the development of future instrument calibration and validation plans.

  7. SAR calibration: an overview

    Microsoft Academic Search

    Anthony Freeman

    1992-01-01

    Progress in synthetic-aperture radar, (SAR) calibration is reviewed. The difficulties of calibrating both airborne and spaceborne SAR image data are addressed. The quantities measured by a SAR, i.e. radar backscatter, are defined and mathematical formulations for the three basic types of SAR image are developed. The difficulties in establishing science requirements for calibration are discussed. The measurement of SAR image

  8. Infrared Irradiance Calibration

    Microsoft Academic Search

    Stephan D. Price

    2004-01-01

    Infrared astronomical measurements are calibrated against reference sources, usually primary standard stars that are, in turn, calibrated either by direct or indirect means. A direct calibration compares the star with a certified source, typically a blackbody. Indirect methods extrapolate a direct measurement of the flux at one wavelength to the flux at another. Historically, alpha Lyr (Vega) has been used

  9. Infrared Irradiance Calibration

    Microsoft Academic Search

    Stephan D. Price

    2004-01-01

    Infrared astronomical measurements are calibrated against reference sources, usually primary standard stars that are, in turn, calibrated either by direct or indirect means. A direct calibration compares the star with a certified source, typically a blackbody. Indirect methods extrapolate a direct measurement of the flux at one wavelength to the flux at another. Historically, a Lyr (Vega) has been used

  10. Infrared irradiance calibration

    Microsoft Academic Search

    Stephan D. Price

    2004-01-01

    Infrared astronomical measurements are calibrated against reference sources, usually primary standard stars that are, in turn, calibrated either by direct or indirect means. A direct calibration compares the star with a certified source, typically a blackbody. Indirect methods extrapolate a direct measurement of the flux at one wavelength to the flux at another. Historically, ? Lyr (Vega) has been used

  11. The Effects of Focus-Skin Distance and Shaping Block Tray on the Calibration Factor of In-Vivo Dosimetry Diodes

    Microsoft Academic Search

    Angelo Ostinelli; Stefania Gelosa; Marco Cacciatori; Milena Frigerio; Angelo Monti; Paola Tognoli

    2000-01-01

    Purpose: In-vivo dose measurements during conformal treatments require correction factor evaluations for differences in block shapes, filed size and source-skin distance (SSD). The aim of this paper is to evaluate a single correction factor, CFSSDentrance, depending only on source-skin distance, which takes into account both shape and size of blocked fields, in pelvic treatments. Materials and Methods: A set of

  12. Innovative Imaging Spectrometer Calibration Techniques

    NASA Technical Reports Server (NTRS)

    Chrien, T.; Chovit, C.; Eastwood, M.

    1995-01-01

    A laboratory calibration of the Airborne Visible Infrared Imaging Spectrometer (AVIRIS) allowed experimentation with several innovative calibration techniques that would improve calibration accuracy, provide independent checks for systematic errors, and reduce the time required to collect a calibration data set.

  13. Nonlinear Observers for Gyro Calibration

    NASA Technical Reports Server (NTRS)

    Thienel, Julie; Sanner, Robert M.

    2003-01-01

    Nonlinear observers for gyro calibration are presented. The first observer estimates a constant gyro bias. The second observer estimates scale factor errors. The third observer estimates the gyro alignment for three orthogonal gyros. The convergence properties of all three observers are discussed. Additionally, all three observers are coupled with a nonlinear control algorithm. The stability of each of the resulting closed loop systems is analyzed. Simulated test results are presented for each system.

  14. Direct megavoltage photon calibration service in Australia

    PubMed Central

    Ramanathan, G.; Oliver, C.; Cole, A.; Lye, J.; Harty, P. D.; Wright, T.; Webb, D. V.; Followill, D. S.

    2014-01-01

    The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) maintains the Australian primary standard of absorbed dose. Until recently, the standard was used to calibrate ionisation chambers only in 60Co gamma rays. These chambers are then used by radiotherapy clinics to determine linac output, using a correction factor (kQ) to take into account the different spectra of 60Co and the linac. Over the period 2010–2013, ARPANSA adapted the primary standard to work in megavoltage linac beams, and has developed a calibration service at three photon beams (6, 10 and 18 MV) from an Elekta Synergy linac. We describe the details of the new calibration service, the method validation and the use of the new calibration factors with the International Atomic Energy Agency’s TRS-398 dosimetry Code of Practice. The expected changes in absorbed dose measurements in the clinic when shifting from 60Co to the direct calibration are determined. For a Farmer chamber (model 2571), the measured chamber calibration coefficient is expected to be reduced by 0.4, 1.0 and 1.1 % respectively for these three beams when compared to the factor derived from 60Co. These results are in overall agreement with international absorbed dose standards and calculations by Muir and Rogers in 2010 of kQ factors using Monte Carlo techniques. The reasons for and against moving to the new service are discussed in the light of the requirements of clinical dosimetry. PMID:25146559

  15. Residual gas analyzer calibration

    NASA Technical Reports Server (NTRS)

    Lilienkamp, R. H.

    1972-01-01

    A technique which employs known gas mixtures to calibrate the residual gas analyzer (RGA) is described. The mass spectra from the RGA are recorded for each gas mixture. This mass spectra data and the mixture composition data each form a matrix. From the two matrices the calibration matrix may be computed. The matrix mathematics requires the number of calibration gas mixtures be equal to or greater than the number of gases included in the calibration. This technique was evaluated using a mathematical model of an RGA to generate the mass spectra. This model included shot noise errors in the mass spectra. Errors in the gas concentrations were also included in the valuation. The effects of these errors was studied by varying their magnitudes and comparing the resulting calibrations. Several methods of evaluating an actual calibration are presented. The effects of the number of gases in then, the composition of the calibration mixture, and the number of mixtures used are discussed.

  16. Calibration of the NPL secondary standard radionuclide calibrator for 32P, 89Sr and 90Y

    NASA Astrophysics Data System (ADS)

    Woods, M. J.; Munster, A. S.; Sephton, J. P.; Lucas, S. E. M.; Walsh, C. Paton

    1996-02-01

    Pure beta particle emitting radionuclides have many therapeutic applications in nuclear medicine. The response of the NPL secondary standard radionuclide calibrator to 32P, 89Sr and 90Y has been measured using accurately calibrated solutions. For this purpose, high efficiency solid sources were prepared gravimetrically from dilute solutions of each radionuclide and assayed in a 4? proportional counter; the source activities were determined using known detection efficiency factors. Measurements were made of the current response (pA/MBq) of the NPL secondary standard radionuclide calibrator using the original concentrated solutions. Calibration figures have been derived for 2 and 5 ml British Standard glass ampoules and Amersham International plc P6 vials. Volume correction factors have also been determined. Gamma-ray emitting contaminants can have a disproportionate effect on the calibrator response and particular attention has been paid to this.

  17. Field calibration of reference reflectance panels

    NASA Technical Reports Server (NTRS)

    Jackson, Ray D.; Moran, M. Susan; Slater, Philip N.; Biggar, Stuart F.

    1987-01-01

    A procedure for calibrating reference reflectance panels using the sun as the radiation source and a pressed-polytetrafluoroethylene powder standard is described. The directional/directional reflectance factor and the directional/hemispheric reflectance factor are examined. Directional/directional voltage responses for pressed-halon are analyzed. Three painted BaSO4 and one painted halon were calibrated using the proposed procedure. The effects of diffuse irradiance on reflectance-factor measurements are investigated. It is determined that the method has an accuracy on the order of 1 percent. The advantages and disadvantages of this method are discussed.

  18. On-Orbit Calibration of Satellite Gyroscopes

    NASA Technical Reports Server (NTRS)

    Hashmall, Joseph A.; Radomski, Mark; Sedlak, Joseph; Harman, Richard (Technical Monitor)

    2000-01-01

    In order to maneuver satellites accurately from one attitude to another, onboard rate sensing gyroscopes usually must be calibrated after launch. Several algorithms have been used to determine gyro biases, misalignments, and scale factors. This paper describes algorithms that have been used in the past, discusses their advantages and limitations, and describes a new algorithm and the gyro calibration results obtained using this new algorithm. The new algorithm has significant operational advantages in addition to being at least as accurate as other algorithms.

  19. A time and motion study of peripheral venous catheter flushing practice using manually prepared and prefilled flush syringes.

    PubMed

    Keogh, Samantha; Marsh, Nicole; Higgins, Niall; Davies, Karen; Rickard, Claire

    2014-01-01

    Peripheral venous catheters (PVCs) are the simplest and most frequently used method for drug, fluid, and blood product administration in the hospital setting. It is estimated that up to 90% of patients in acute care hospitals require a PVC; however, PVCs are associated with inherent complications, which can be mechanical or infectious. There have been a range of strategies to prevent or reduce PVC-related complications that include optimizing patency through the use of flushing. Little is known about the current status of flushing practice. This observational study quantified preparation and administration time and identified adherence to principles of Aseptic Non-Touch Technique and organizational protocol on PVC flushing by using both manually prepared and prefilled syringes. PMID:24583939

  20. Factoring

    NSDL National Science Digital Library

    Mrs. Taylor

    2010-10-19

    In this lesson we will explore prime numbers and factors A prime number has only two factors, 1 and itself. The Greek scholar, Eratosthenes of Cyrene lived from approximately 275 to 195 BC. He is know for being the first to have computed the size of the Earth and served as the director of the famous library in

  1. Factorize

    NSDL National Science Digital Library

    2010-01-01

    In this activity, students find factor pairs for a given number and then create a rectangle with those dimensions on a coordinate plane. This activity allows students to explore factorizations of numbers and how they relate to rectangles with that number as an area. This activity includes supplemental materials, including background information about the topics covered, a description of how to use the application, and exploration questions for use with the java applet.

  2. A multicenter, open-label, phase II study of the immunogenicity and safety of a new prefilled syringe (liquid) formulation of avonex in patients with multiple sclerosis

    Microsoft Academic Search

    J. Theodore Phillips; George Rice; Elliot Frohman; Luc Vande Gaer; Thomas Scott; Judith Haas; Eric Eggenberger; Mark S Freedman; William Stuart; Luis Cunha; Lawrence Jacobs; Joel Oger; Douglas Arnold; T Jock Murray; Mary DiBiase; Vijay Jethwa; Susan Goelz

    2004-01-01

    Background: A new liquid formulation of Avonex (interferon beta-1a [IFN?-1a]) in a prefilled syringe has been developed to make administration of the drug easier for patients with multiple sclerosis (MS). This formulation does not contain human serum albumin (HSA), often added to interferon (IFN) products for stabilization. However, formulation changes may alter the secondary, tertiary, and quaternary structures of IFN?

  3. Assessment of an in vitro whole cigarette smoke exposure system: The Borgwaldt RM20S 8-syringe smoking machine

    PubMed Central

    2011-01-01

    Background There have been many recent developments of in vitro cigarette smoke systems closely replicating in vivo exposures. The Borgwaldt RM20S smoking machine (RM20S) enables the serial dilution and delivery of cigarette smoke to exposure chambers for in vitro analyses. In this study we have demonstrated reliability and robustness testing of the RM20S in delivering smoke to in vitro cultures using an in-house designed whole smoke exposure chamber. Results The syringe precision and accuracy of smoke dose generated by the RM20S was assessed using a methane gas standard and resulted in a repeatability error of ?9%. Differential electrical mobility particle spectrometry (DMS) measured smoke particles generated from reference 3R4F cigarettes at points along the RM20S. 53% ± 5.9% of particles by mass reached the chamber, the remainder deposited in the syringe or connecting tubing and ~16% deposited in the chamber. Spectrofluorometric quantification of particle deposition within chambers indicated a positive correlation between smoke concentration and particle deposition. In vitro air-liquid interface (ALI) cultures (H292 lung epithelial cells), exposed to whole smoke (1:60 dilution (smoke:air, equivalent to ~5 ?g/cm2)) demonstrated uniform smoke delivery within the chamber. Conclusions These results suggest this smoke exposure system is a reliable and repeatable method of generating and exposing ALI in vitro cultures to cigarette smoke. This system will enable the evaluation of future tobacco products and individual components of cigarette smoke and may be used as an alternative in vitro tool for evaluating other aerosols and gaseous mixtures such as air pollutants, inhaled pharmaceuticals and cosmetics. PMID:21867559

  4. Identification of epidural space using loss of resistance syringe, infusion drip, and balloon technique: A comparative study

    PubMed Central

    Singhal, Suresh; Bala, Manju; Kaur, Kiranpreet

    2014-01-01

    Background and Objective: There are various techniques to identify epidural space but superiority of one technique over other has not been adequately studied. We conducted a study to Compare and evaluate the three techniques for epidural space localization that is, loss of resistance (LOR) syringe technique, balloon technique and drip infusion technique. Materials and Methods: Seventy-five patients of either sex, belonging to American Society of Anesthesiologists physical status Class 1 or 2, between 20 and 50 years of age, scheduled to undergo lower abdominal and lower limb surgeries were randomly allocated to one of the three groups (n = 25 each) depending upon epidural space localization. In Group I, epidural space localization was done with LOR syringe technique. In Group II Balloon technique and in Group III drip infusion technique was used. Distance of the epidural space from skin, number of attempts, time taken for epidural space localization and quality of the block were the parameter recorded during the study. Results: First attempt success rate for epidural space localization was highest in Group III (100%). The mean time taken for epidural space localization was least in Group III, and when compared with other groups it was found to be statistically significant with P = 0.016. Number of attempt for space localization and success rate of the block was better in the majority of patients of Group III, but the difference was found to be statistically nonsignificant. Complication rate was almost negligible in all three techniques. Conclusion: We conclude that the time taken to localize the epidural space was least in drip infusion technique. As for number of attempts, quality of the block and complications is concerned, all the three techniques are comparable. PMID:25538520

  5. Comparison of NovoPen 3 and syringes/vials in the acceptance of insulin therapy in NIDDM patients with secondary failure to oral hypoglycaemic agents.

    PubMed

    Kadiri, A; Chraibi, A; Marouan, F; Ababou, M R; el Guermai, N; Wadjinny, A; Kerfati, A; Douiri, M; Bensouda, J D; Belkhadir, J; Arvanitis, Y

    1998-07-01

    This open, randomised, cross-over study compared the acceptance and safety of NovoPen 3 with that of conventional syringes and vials when initiating insulin treatment in 96 NIDDM patients with secondary failure to oral hypoglycaemic agents. These patients had not previously been treated with insulin. All patients used each insulin administration system for 12 weeks. Group A started therapy using NovoPen 3 and crossed over to syringe/vial administration; Group B started with syringe/vial administration followed by NovoPen 3. In total, 78 patients completed the study. Most patients in Group A initially found the insulin injections very easy or easy and many of those who found injections easy at first found them very easy by the end of week 12. During the first period, patients in Group B found insulin administration more difficult than those in Group A. Injection pain was significantly lower with NovoPen 3 than with syringes and vials (P = 0.0018). Patients in Group B reported a significantly lower level of injection pain after the switch to using NovoPen 3 (P = 0.0003). Acceptance of insulin injections was significantly higher by patients using NovoPen 3 than by those using syringes and vials (P = 0.0059). Setting and drawing up the dose of insulin was also easier for patients using NovoPen 3 (P = 0.0490). At the end of the study, most patients (89.5% (68/76 replies)) said that they preferred NovoPen 3 to syringes and vials. Glycaemic control improved compared with baseline after starting insulin therapy, with no differences between Groups A and B, or between the two injection systems. The number of reported hypoglycaemic episodes was very low and was not significantly different between Groups A and B, or between the two administration systems. No treatment-related adverse events were reported. We conclude that use of NovoPen 3 provides better acceptance of insulin injection than use of conventional syringes and vials during initiation of insulin therapy in NIDDM patients with secondary failure to treatment with oral hypoglycaemic agents. PMID:9768368

  6. Are adrenaline autoinjectors fit for purpose? A pilot study of the mechanical and injection performance characteristics of a cartridge-versus a syringe-based autoinjector

    PubMed Central

    Schwirtz, Andreas; Seeger, Harald

    2010-01-01

    Background: Adrenaline autoinjectors (AAIs) are prescribed to facilitate the intramuscular administration of adrenaline in patients diagnosed with life-threatening anaphylaxis. This pilot study investigated the injection and functional properties of two AAIs (deploying different delivery systems) under standard conditions, after dynamic and mechanical stresses, and in the presence of denim. Methods: The differences between a cartridge-based AAI (EpiPen® Junior) and a syringe-based AAI (Anapen® Junior) were assessed using three sets of tests. Test 1: under standard conditions, the injection depth and dose were measured in ballistic gelatine (a validated tissue simulant). Test 2: before the safety cap removal and activation forces were measured, AAIs were subjected to either of two preconditioning tests: 1) free-fall drop test; or 2) static load (ie, 400 N, equivalent to 40 kg weight) test; or 3) no preconditioning. Test 3: under standard conditions, injection properties into ballistic gelatine in the presence and absence of denim were investigated. Statistical analyses were performed using the Student’s t-test or Welch’s test. Results: The maximum depth of delivery was significantly greater with cartridge AAI (n = 4, mean 21.09 ± 2.54 mm) than with syringe AAI (n = 5; mean 11.64 ± 0.80 mm; P = 0.003). After 2.5 seconds, cartridge AAI (n = 4) discharged significantly more dose than syringe AAI (n = 3; 74.3% versus 25.7% of total dose; P = 0.001). Both cartridge and syringe AAI withstood the free-fall drop test, but almost all devices failed to activate following the static load test. Under standard conditions, significantly less force was required to remove the safety cap of cartridge AAI than syringe AAI (both n = 15; mean 9.56 ± 2.36 N versus 20.23 ± 6.61 N, respectively; P < 0.001), but a significantly greater activation force was required for cartridge AAI than syringe AAI (mean 23.01 ± 3.96 N versus 8.06 ± 0.51 N, respectively; P < 0.001). The presence of denim did not alter the activation force or effective needle length of either of the AAIs. Conclusion: Cartridge AAI appears significantly more capable of consistently and rapidly delivering a clinically relevant dose of intramuscular adrenaline than syringe AAI. However, both devices showed shortcomings in their ability to sustain mechanical stress similar to that which is likely over their shelf life, and as such, may not be fit for life-saving purpose. PMID:21437050

  7. Metrology and Calibration Standards

    NSDL National Science Digital Library

    Equipment calibration issues are the name of the game here. Topics addressed range from "the adjustment dilemma" to terminology (for example "calibration" vs. "verification") to worldwide calibration standards. The site is sponsored by Agilent Technologies, a company that provides the semiconductor, electronics, communications, and related industries with testing solutions for test instruments, systems, equipment and monitoring tools. Users can be sure that every measurement is traceable to National Metrology Institutes (NMIs) through Agilent-engineered calibration procedures that verify instrument specifications. The site allows users to stay up-to-date on changing compliance requirements and their practical applications by working with Agilent meteorologists who collaborate with international standards organizations.

  8. ATLAS Muon Calibration Framework

    NASA Astrophysics Data System (ADS)

    Carlino, Gianpaolo; De Salvo, Alessandro; Di Simone, Andrea; Doria, Alessandra; Jha, Manoj Kumar; Mazzaferro, Luca; Walker, Rodney; ATLAS Collaboration

    2011-12-01

    Automated calibration of the ATLAS detector subsystems (like MDT and RPC chambers) are being performed at remote sites, called Remote Calibration Centers. The calibration data for the assigned part of the detector are being processed at these centers and send the result back to CERN for general use in reconstruction and analysis. In this work, we present the recent developments in data discovery mechanism and integration of Ganga as a backend which allows for the specification, submission, bookkeeping and post processing of calibration tasks on a wide set of available heterogeneous resources at remote centers.

  9. Cumulative sum quality control for calibrated breast density measurements

    SciTech Connect

    Heine, John J.; Cao Ke; Beam, Craig [Cancer Prevention and Control Division, Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, Florida 33612 (United States); Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, 1603 W. Taylor St., Chicago, Illinois 60612 (United States)

    2009-12-15

    Purpose: Breast density is a significant breast cancer risk factor. Although various methods are used to estimate breast density, there is no standard measurement for this important factor. The authors are developing a breast density standardization method for use in full field digital mammography (FFDM). The approach calibrates for interpatient acquisition technique differences. The calibration produces a normalized breast density pixel value scale. The method relies on first generating a baseline (BL) calibration dataset, which required extensive phantom imaging. Standardizing prospective mammograms with calibration data generated in the past could introduce unanticipated error in the standardized output if the calibration dataset is no longer valid. Methods: Sample points from the BL calibration dataset were imaged approximately biweekly over an extended timeframe. These serial samples were used to evaluate the BL dataset reproducibility and quantify the serial calibration accuracy. The cumulative sum (Cusum) quality control method was used to evaluate the serial sampling. Results: There is considerable drift in the serial sample points from the BL calibration dataset that is x-ray beam dependent. Systematic deviation from the BL dataset caused significant calibration errors. This system drift was not captured with routine system quality control measures. Cusum analysis indicated that the drift is a sign of system wear and eventual x-ray tube failure. Conclusions: The BL calibration dataset must be monitored and periodically updated, when necessary, to account for sustained system variations to maintain the calibration accuracy.

  10. AUTOMATED CALIBRATION BENCH FOR CALIBRATION OF RADIATION THERMOMETERS

    Microsoft Academic Search

    Valentin Batagelj; Jovan Bojkovski

    2009-01-01

    In order to improve and optimize the procedure for calibration of radiation thermometers, an automated calibration bench was developed. Manual calibration with the help of special stands is time consuming and less reliable compared to automated calibration. The developed calibration bench has 5 degree of freedom (DOF) (3 translation joints and 2 rotation joints). For each axis we have used

  11. Calibration of hydrometers

    Microsoft Academic Search

    Salvatore Lorefice; Andrea Malengo

    2006-01-01

    After a brief description of the different methods employed in periodic calibration of hydrometers used in most cases to measure the density of liquids in the range between 500 kg m-3 and 2000 kg m-3, particular emphasis is given to the multipoint procedure based on hydrostatic weighing, known as well as Cuckow's method. The features of the calibration apparatus and

  12. OLI Radiometric Calibration

    NASA Technical Reports Server (NTRS)

    Markham, Brian; Morfitt, Ron; Kvaran, Geir; Biggar, Stuart; Leisso, Nathan; Czapla-Myers, Jeff

    2011-01-01

    Goals: (1) Present an overview of the pre-launch radiance, reflectance & uniformity calibration of the Operational Land Imager (OLI) (1a) Transfer to orbit/heliostat (1b) Linearity (2) Discuss on-orbit plans for radiance, reflectance and uniformity calibration of the OLI

  13. Improved Regression Calibration

    ERIC Educational Resources Information Center

    Skrondal, Anders; Kuha, Jouni

    2012-01-01

    The likelihood for generalized linear models with covariate measurement error cannot in general be expressed in closed form, which makes maximum likelihood estimation taxing. A popular alternative is regression calibration which is computationally efficient at the cost of inconsistent estimation. We propose an improved regression calibration…

  14. Bayesian analysis of a flow meter calibration problem

    NASA Astrophysics Data System (ADS)

    Kok, G. J. P.; van der Veen, A. M. H.; Harris, P. M.; Smith, I. M.; Elster, C.

    2015-04-01

    A turbine flow meter indicates the volume of fluid flowing through the device per unit of time. Such a flow meter is commonly calibrated at a few known flow rates over its measurement range. A calibration curve relating the pulse factor of the meter to the flow rate is then fitted to calibration data using an ordinary least squares approach. This approach does not consider prior knowledge that may exist about the flow meter or the calibration procedure. A Bayesian analysis enables prior knowledge to be taken into account. A Bayesian inference results in a posterior distribution for the unknown parameters of the calibration curve that may be seen as the most comprehensive uncertainty information about these unknowns. This paper investigates for a flow meter calibration problem the effects of appreciating prior knowledge on values of the calibration curve and their associated uncertainties. It presents the results of a Bayesian analysis and compares them to those obtained by an ordinary least squares approach.

  15. GRAVITY: the calibration unit

    NASA Astrophysics Data System (ADS)

    Blind, N.; Eisenhauer, F.; Haug, M.; Gillessen, S.; Lippa, Magdalena; Burtscher, L.; Hans, O.; Haussmann, F.; Huber, S.; Janssen, A.; Kellner, S.; Kok, Y.; Ott, T.; Pfuhl, O.; Sturm, E.; Weber, J.; Wieprecht, E.; Amorim, A.; Brandner, W.; Perrin, G.; Perraut, K.; Straubmeier, C.

    2014-07-01

    We present in this paper the design and characterisation of a new sub-system of the VLTI 2nd generation instrument GRAVITY: the Calibration Unit. The Calibration Unit provides all functions to test and calibrate the beam combiner instrument: it creates two artificial stars on four beams, and dispose of four delay lines with an internal metrology. It also includes artificial stars for the tip-tilt and pupil guiding systems, as well as four metrology pick-up diodes, for tests and calibration of the corresponding sub-systems. The calibration unit also hosts the reference targets to align GRAVITY to the VLTI, and the safety shutters to avoid the metrology light to propagate in the VLTI-lab. We present the results of the characterisation and validtion of these differrent sub-units.

  16. Sandia WIPP calibration traceability

    SciTech Connect

    Schuhen, M.D. [Sandia National Labs., Albuquerque, NM (United States)] [Sandia National Labs., Albuquerque, NM (United States); Dean, T.A. [RE/SPEC, Inc., Albuquerque, NM (United States)] [RE/SPEC, Inc., Albuquerque, NM (United States)

    1996-05-01

    This report summarizes the work performed to establish calibration traceability for the instrumentation used by Sandia National Laboratories at the Waste Isolation Pilot Plant (WIPP) during testing from 1980-1985. Identifying the calibration traceability is an important part of establishing a pedigree for the data and is part of the qualification of existing data. In general, the requirement states that the calibration of Measuring and Test equipment must have a valid relationship to nationally recognized standards or the basis for the calibration must be documented. Sandia recognized that just establishing calibration traceability would not necessarily mean that all QA requirements were met during the certification of test instrumentation. To address this concern, the assessment was expanded to include various activities.

  17. Unassisted 3D camera calibration

    NASA Astrophysics Data System (ADS)

    Atanassov, Kalin; Ramachandra, Vikas; Nash, James; Goma, Sergio R.

    2012-03-01

    With the rapid growth of 3D technology, 3D image capture has become a critical part of the 3D feature set on mobile phones. 3D image quality is affected by the scene geometry as well as on-the-device processing. An automatic 3D system usually assumes known camera poses accomplished by factory calibration using a special chart. In real life settings, pose parameters estimated by factory calibration can be negatively impacted by movements of the lens barrel due to shaking, focusing, or camera drop. If any of these factors displaces the optical axes of either or both cameras, vertical disparity might exceed the maximum tolerable margin and the 3D user may experience eye strain or headaches. To make 3D capture more practical, one needs to consider unassisted (on arbitrary scenes) calibration. In this paper, we propose an algorithm that relies on detection and matching of keypoints between left and right images. Frames containing erroneous matches, along with frames with insufficiently rich keypoint constellations, are detected and discarded. Roll, pitch yaw , and scale differences between left and right frames are then estimated. The algorithm performance is evaluated in terms of the remaining vertical disparity as compared to the maximum tolerable vertical disparity.

  18. COBE ground segment gyro calibration

    NASA Technical Reports Server (NTRS)

    Freedman, I.; Kumar, V. K.; Rae, A.; Venkataraman, R.; Patt, F. S.; Wright, E. L.

    1991-01-01

    Discussed here is the calibration of the scale factors and rate biases for the Cosmic Background Explorer (COBE) spacecraft gyroscopes, with the emphasis on the adaptation for COBE of an algorithm previously developed for the Solar Maximum Mission. Detailed choice of parameters, convergence, verification, and use of the algorithm in an environment where the reference attitudes are determined form the Sun, Earth, and star observations (via the Diffuse Infrared Background Experiment (DIRBE) are considered. Results of some recent experiments are given. These include tests where the gyro rate data are corrected for the effect of the gyro baseplate temperature on the spacecraft electronics.

  19. Airdata Measurement and Calibration

    NASA Technical Reports Server (NTRS)

    Haering, Edward A., Jr.

    1995-01-01

    This memorandum provides a brief introduction to airdata measurement and calibration. Readers will learn about typical test objectives, quantities to measure, and flight maneuvers and operations for calibration. The memorandum informs readers about tower-flyby, trailing cone, pacer, radar-tracking, and dynamic airdata calibration maneuvers. Readers will also begin to understand how some data analysis considerations and special airdata cases, including high-angle-of-attack flight, high-speed flight, and nonobtrusive sensors are handled. This memorandum is not intended to be all inclusive; this paper contains extensive reference and bibliography sections.

  20. Integrating Health and Prevention Services in Syringe Access Programs: A Strategy to Address Unmet Needs in a High-Risk Population

    PubMed Central

    Storm, Deborah S.; Hoyt, Mary Jo; Dutton, Loretta; Berezny, Linda; Allread, Virginia; Paul, Sindy

    2014-01-01

    Injection drug users are at a high risk for a number of preventable diseases and complications of drug use. This article describes the implementation of a nurse-led health promotion and disease prevention program in New Jersey's syringe access programs. Initially designed to target women as part of a strategy to decrease missed opportunities for perinatal HIV prevention, the program expanded by integrating existing programs and funding streams available through the state health department. The program now offers health and prevention services to both men and women, with 3,488 client visits in 2011. These services extend the reach of state health department programs, such as adult vaccination and hepatitis and tuberculosis screening, which clients would have had to seek out at multiple venues. The integration of prevention, treatment, and health promotion services in syringe access programs reaches a vulnerable and underserved population who otherwise may receive only urgent and episodic care. PMID:24385646

  1. Determination of clenbuterol from pork samples using surface molecularly imprinted polymers as the selective sorbents for microextraction in packed syringe.

    PubMed

    Du, Wei; Lei, Chunmei; Zhang, Siruo; Bai, Gang; Zhou, Huiyan; Sun, Min; Fu, Qiang; Chang, Chun

    2014-03-01

    In this study, a selective sample pretreatment procedure combing surface molecularly imprinted polymers and microextraction in packed syringe (SMIPs-MEPS) was developed for the analysis of clenbuterol (CLB) from pork samples. SMIPs for CLB were synthesized on silica gel particles through a sol-gel process. A series of characterization and adsorption experiments revealed that the SMIPs exhibited porous structures, good thermal stability, high adsorption capacity and a fast mass transfer rate. The obtained SMIPs were employed as selective sorbents of SMIPs-MEPS for extraction of CLB from pork samples. Several parameters affecting the extraction efficiency were investigated, including the pH of sample solution, number of draw-eject cycles, volume of sample, type and volume of washing solution, and the type and volume of elution solution. Under the optimized conditions, a simple and rapid method for the determination of CLB from pork samples was established by coupling with high performance liquid chromatography (HPLC). The whole pretreatment process was rapid and it can be accomplished with 2min. The limit of quantitation and the limit of detection for CLB were 0.02 and 0.009?gkg(-1), respectively. The average recoveries of CLB at three spiked levels ranged from 86.5% to 91.2% with the relative standard deviations (RSD) ?6.3%. PMID:24463040

  2. Water-compatible poly (hydroxyethyl methacrylate) polymer sorbent for miniaturized syringe assisted extraction of sulfonamides in milk.

    PubMed

    Gao, Mengmeng; Yan, Hongyuan; Sun, Ning

    2013-10-24

    A simple, convenient, and economic self-assembly miniaturized syringe assisted extraction (mini-SAE) using poly (hydroxyethyl methacrylate) polymer (PHEMA) as sorbent coupled with liquid chromatography was proposed for rapid screening of sulfadiazine (SD) and sulfamonomethoxine (SMM) in milk. The water-compatible PHEMA was synthesized by reversible addition-fragmentation chain transfer precipitation polymerization using trithiocarbonate as chain transfer agent and methanol-water system as reaction medium. The obtained PHEMA sorbent showed good affinity to sulfonamides and was successfully applied as a special sorbent for a mini-SAE device for simultaneous extraction and isolation of SD and SMM in milk samples. Under the optimum condition, good linearity was obtained in a range of 7.0-700 ng g(-1) (r?0.9995) and the average recoveries of SD and SMM at three spiked levels were ranged from 85.6 to 100.3% with the relative standard deviations (RSD) ?6.5%. The presented PHEMA-mini-SAE protocol could be potentially applied as an alternative tool for analyzing the residues of SAs in complicated biological samples. PMID:24120166

  3. Poor uptake of community based sexually transmissible infection testing at an inner city needle and syringe program.

    PubMed

    Martin, Lynne; Crawford, Sione; Knight, Vickie; Bath, Nicky; McNulty, Anna

    2013-05-01

    Sydney Sexual Health Centre (SSHC) and the NSW Users and AIDS Association (NUAA), the NSW peer-based drug user organisation, pilot tested an outreach sexually transmissible infection (STI) testing station using self-collected urine and swabs in NUAA's needle and syringe program (NSP) space. The model was based on SSHC's established Xpress clinic. A needs assessment among NUAA clients was undertaken prior to commencement in order to ascertain potential uptake. A computer-assisted self interview was developed with data securely transferred to SSHC daily. During the 6 months from January to July 2011, almost 3000 occasions of service were recorded in the NSP from an estimated 375 clients. Four clients took advantage of NUAA Xpress during this time. Despite initial client interest, promotional efforts and the success of this methodology elsewhere, this outreach model did not have a successful uptake and was discontinued. This project provides value in considering the methodology and implementation of future outreach STI testing projects for people who inject drugs. PMID:23158773

  4. Evaluation of Syringe?Connected Minicolumn Technique for Preconcentration of Some Trace Elements Using Chromosorb?103 and Determination by Flame Atomic Absorption Spectrometry

    Microsoft Academic Search

    Yasemin Bakircioglu; Dilek Bakircioglu; Suleyman Akman

    2004-01-01

    A syringe?connected minicolumn (SCM) technique has been developed for preconcentration and enrichment of cobalt, iron, and lead in river?water samples prior to their determination by flame atomic absorption spectrometry (FAAS). The proposed technique is substituted for the classical batch and column techniques all of which are off?line methods. The method proposed was compared with the column technique with respect to

  5. Determination of ammonium in aqueous samples using new headspace dynamic in-syringe liquid-phase microextraction with in situ derivitazation coupled with liquid chromatography-fluorescence detection.

    PubMed

    Muniraj, Sarangapani; Yan, Cheing-Tong; Shih, Hou-Kung; Ponnusamy, Vinoth Kumar; Jen, Jen-Fon

    2012-11-19

    A new simultaneous derivatization and extraction method for the preconcentration of ammonia using new one-step headspace dynamic in-syringe liquid-phase microextraction with in situ derivatization was developed for the trace determination of ammonium in aqueous samples by liquid chromatography with fluorescence detection (LC-FLD). The acceptor phase (as derivatization reagent) containing o-phthaldehyde and sodium sulfite was held within a syringe barrel and immersed in the headspace of sample container. The gaseous ammonia from the alkalized aqueous sample formed a stable isoindole derivative with the acceptor phase inside the syringe barrel through the reciprocated movements of plunger. After derivatization-cum-extraction, the acceptor phase was directly injected into LC-FLD for analysis. Parameters affecting the ammonia evolution and the extraction/derivatization efficiency such as sample matrix, pH, temperature, sampling time, and the composition of derivatization reagent, reaction temperature, and frequency of reciprocated plunger, were studied thoroughly. Results indicated that the maximum extraction efficiency was obtained by using 100?L derivatization reagent in a 1-mL gastight syringe under 8 reciprocated movements of plunger per min to extract ammonia evolved from a 20mL alkalized aqueous solution at 70°C (preheated 4min) with 380rpm stirring for 8min. The detection was linear in the concentration range of 0.625-10?M with the correlation coefficient of 0.9967 and detection limit of 0.33?M (5.6ng mL(-1)) based on SN(-1)=3. The method was applied successfully to determine ammonium in real water samples without any prior cleanup of the samples, and has been proved to be a simple, sensitive, efficient and cost-effective procedure for trace ammonium determination in aqueous samples. PMID:23140954

  6. Calibrating the Younger Dryas

    NSDL National Science Digital Library

    Calibrating the Younger Dryas Contributed by: Thom Davis, Greg Wiles, Roger Brown, David Bary This activity was developed during the Teaching Climate Change from the Geological Record workshop, held in August ...

  7. Inversion Recovery with Embedded Self-Calibration (IRES)

    PubMed Central

    Tan, Ek T.; Riederer, Stephen J.

    2009-01-01

    With self-calibrated parallel acquisition, the calibration data used to characterize coil response are acquired within the actual, parallel scan. Although this eliminates the need for a separate calibration scan, it reduces the net acceleration factor of the parallel scan. Furthermore, this reduction gets worse at higher accelerations. A method is described for 3D inversion recovery gradient-echo imaging in which calibration is incorporated into the sequence but with no loss of net acceleration. This is done by acquiring the calibration data using very small (?4°) tip angle acquisitions during the delay interval after acquisition of the accelerated imaging data. The technique is studied at 3T with simulation, phantom and in vivo experiments using both image space-based and k-space-based parallel reconstruction methods. At nominal acceleration factors of three and four, the newly described Inversion Recovery with Embedded Self-calibration (IRES) method can retain effective acceleration with comparable SNR and contrast to standard self-calibration. At a net 2D acceleration factor of four, IRES can achieve higher SNR than standard self-calibration having a nominal acceleration factor of six but the same acquisition time. PMID:19365864

  8. Double Chooz Calibration

    NASA Astrophysics Data System (ADS)

    Ostrovskiy, Igor; Double Chooz Collaboration

    2012-08-01

    The current best limit on the neutrino mixing angle ?13(sin2(2?13)?0.15@90%C.L.) was established by Chooz experiment. The Double Chooz experiment is being prepared and is aiming to surpass the limit by almost an order of magnitude. Extensive calibration program is necessary to achieve the claimed sensitivity. Dedicated embedded and deployable calibration systems developed for Double Chooz are described.

  9. Double Chooz Laser Calibration

    NASA Astrophysics Data System (ADS)

    Sun, Yujing

    2013-04-01

    The Double Chooz experiment focuses on measuring the neutrino mixing angle without the ambiguity of matter effects and CP violation. A multi-detector setup can extend the reach in sensitivity for theta-13 with reduced systematic error. Two identical detectors, the far and the near, are constructed at 1050 m and 400 m respectively, from the Chooz nuclear cores. The far detector is taking data while the near detector is being constructed. The university of alabama group is responsible for the laser calibration system development in both the hardware design and the analysis software including extracting calibration constants of the inner detector PMT gains, charge likelihoods, PMT time offsets and effective speed of light. Two types of lasers are used for the PMT charge and time related calibrations respectively. A UV laser with a wavelength of 380 nm is mainly responsible for the PMT gains and charge likelihoods calibrations. A blue laser of 470 nm wavelength is used in calibrating the PMT time offsets and measuring the speed of light in the medium. In this presentation I will talk about the laser system hardware design and laser calibration data analysis.

  10. Error Modeling and Calibration for Encoded Sun Sensors

    PubMed Central

    Fan, Qiaoyun; Zhang, Guangjun; Li, Jian; Wei, Xinguo; Li, Xiaoyang

    2013-01-01

    Error factors in the encoded sun sensor (ESS) are analyzed and simulated. Based on the analysis results, an ESS error compensation model containing structural errors and fine-code algorithm errors is established, and the corresponding calibration method for model parameters is proposed. As external parameters, installation deviation between ESS and calibration equipment are introduced to the ESS calibration model, so that the model parameters can be calibrated accurately. The experimental results show that within plus/minus 60 degree of incident angle, the ESS measurement accuracy after compensation is three times higher on average than that before compensation. PMID:23470486

  11. Unexplored Indoors method for pyranometers calibration traceable to SI

    NASA Astrophysics Data System (ADS)

    Castillo-Matadamas, H. A.; Molina-Vazquez, J. C.; Quintero-Torres, R.

    2015-01-01

    A method to calibrate pyranometers with direct traceability to the International System of Units (SI) is presented, the method use an electrically calibrated pyroelectric detector (ECPR) as standard and offers numerous advantages over outdoors conventional calibration methods, such as reducing the uncertainty from the reference standard and the final uncertainty of the sensitivity coefficient of the calibrated pyranometer; the measurement uncertainty achieved with this method at normal irradiance is 2.1% for a coverage factor k = 2 and could be reduce if one reduces the uncertainty level of the reference standard.

  12. PHAROS - calibration and software control

    Microsoft Academic Search

    A. Czarny; R. Feiler; E. Pazderski

    2006-01-01

    In this paper we present calibration procedures and software consideration for PHAROS receiver. New calibration with total power back-end is proposed. Simulated results are compared with multi-element phase toggle (MEP) method to verify a new calibration algorithm. Some theoretical basis of calibration procedure are given. Phased arrays for reflector observing systems (PHAROS) software requirements are shown to achieve receiver complexity

  13. Uncertainty estimates for calibration measurements

    Microsoft Academic Search

    A. M. Liebetrau; A. S. Goldman; M. Aparo

    1986-01-01

    The volume of liquid in a process tank is typically determined from a calibration function that relates tank volume to some measure of liquid height. This calibration equation is determined from data acquired during one or more calibration runs. Solutions are proposed for two statistical problems that arise when the calibration function is derived and used: that of computing plausible

  14. Hydrometer calibration by hydrostatic weighing with automated liquid surface positioning

    NASA Astrophysics Data System (ADS)

    Aguilera, Jesus; Wright, John D.; Bean, Vern E.

    2008-01-01

    We describe an automated apparatus for calibrating hydrometers by hydrostatic weighing (Cuckow's method) in tridecane, a liquid of known, stable density, and with a relatively low surface tension and contact angle against glass. The apparatus uses a laser light sheet and a laser power meter to position the tridecane surface at the hydrometer scale mark to be calibrated with an uncertainty of 0.08 mm. The calibration results have an expanded uncertainty (with a coverage factor of 2) of 100 parts in 106 or less of the liquid density. We validated the apparatus by comparisons using water, toluene, tridecane and trichloroethylene, and found agreement within 40 parts in 106 or less. The new calibration method is consistent with earlier, manual calibrations performed by NIST. When customers use calibrated hydrometers, they may encounter uncertainties of 370 parts in 106 or larger due to surface tension, contact angle and temperature effects.

  15. Sodium trifluoroacetate as a tune\\/calibration compound for positive- and negative-ion electrospray ionization mass spectrometry in the mass range of 100–4000 Da

    Microsoft Academic Search

    Mehdi Moini; Bruce L. Jones; Robin M. Rogers; Longfei Jiang

    1998-01-01

    We have identified aqueous:acetonitrile solutions of alkali-metal trifluoroacetate compounds as tune\\/calibration standards\\u000a for both positive- and negative-ion electrospray ionization mass spectrometry (ESI\\/MS). Each alkali-metal trifluoroacetate\\u000a solution in water and acetonitrile (50:50, v\\/v) yields evenly spaced, singly charged peaks in the mass range of 100–3500 Da.\\u000a Intense peaks are formed either by infusing the solution using a syringe pump, by infusing

  16. Calibration Systems Final Report

    SciTech Connect

    Myers, Tanya L.; Broocks, Bryan T.; Phillips, Mark C.

    2006-02-01

    The Calibration Systems project at Pacific Northwest National Laboratory (PNNL) is aimed towards developing and demonstrating compact Quantum Cascade (QC) laser-based calibration systems for infrared imaging systems. These on-board systems will improve the calibration technology for passive sensors, which enable stand-off detection for the proliferation or use of weapons of mass destruction, by replacing on-board blackbodies with QC laser-based systems. This alternative technology can minimize the impact on instrument size and weight while improving the quality of instruments for a variety of missions. The potential of replacing flight blackbodies is made feasible by the high output, stability, and repeatability of the QC laser spectral radiance.

  17. Autonomous Phase Retrieval Calibration

    NASA Technical Reports Server (NTRS)

    Estlin, Tara A.; Chien, Steve A.; Castano, Rebecca; Gaines, Daniel M.; Doubleday, Joshua R.; Schoolcraft, Josua B.; Oyake, Amalaye; Vaughs, Ashton G.; Torgerson, Jordan L.

    2011-01-01

    The Palomar Adaptive Optics System actively corrects for changing aberrations in light due to atmospheric turbulence. However, the underlying internal static error is unknown and uncorrected by this process. The dedicated wavefront sensor device necessarily lies along a different path than the science camera, and, therefore, doesn't measure the true errors along the path leading to the final detected imagery. This is a standard problem in adaptive optics (AO) called "non-common path error." The Autonomous Phase Retrieval Calibration (APRC) software suite performs automated sensing and correction iterations to calibrate the Palomar AO system to levels that were previously unreachable.

  18. Fully automatic exposed and in-syringe dynamic single-drop microextraction with online agitation for the determination of polycyclic musks in surface waters of the Pearl River Estuary and South China Sea.

    PubMed

    Wang, Xiaowei; Yuan, Ke; Liu, Hongtao; Lin, Li; Luan, Tiangang

    2014-07-01

    An automatic exposed and in-syringe dynamic single-drop microextraction method (SDME) for the determination of five polycyclic musks in natural waters was developed using gas chromatography with mass spectrometry. Online agitation was first introduced to the automatic SDME with a magnetic mixer fixed to the bottom of the sample tray of the autosampler. A high enrichment factor (110 ?182) for the target analytes could be achieved after several parameters that affected the microextraction were optimized. The recoveries were between 84.9 and 119.5%, while the limit of detection ranged from 3.4 to 11 ng/L with relative standard deviation < 11.1% for the polycyclic musks. This new SDME mode is fully automatic with great convenience, high enrichment and good reproducibility, and no human intervention. The proposed method was, therefore, successfully applied to determine the polycyclic musks in 31 surface sea waters that were collected from the Pearl River Estuary and the South China Sea. Most polycyclic musks could be detected with the total concentrations ranging from 58.9 to 528.5 ng/L. By using spatial interpolation method of ordinary kriging, the most contaminated area was found near the cities of Dongguan and Guangzhou with local discharge via the major rivers. PMID:24771668

  19. Application of In-Syringe Dispersive Liquid-Liquid Microextraction and Narrow-Bore Tube Dispersive Liquid-Liquid Microextraction for the Determination of Trace Amounts of BTEX in Water Samples.

    PubMed

    Rahmani, Mashaallah; Kaykhaii, Massoud; Ghasemi, Elham; Tahernejad, Mohadeseh

    2015-08-01

    Two new simple and effective methods based on dispersive liquid-liquid microextraction (DLLME) procedure, termed "in-syringe DLLME (IS-DLLME)" and "narrow-bore tube DLLME (NB-DLLME)", were developed and applied for rapid and simultaneous separation and preconcentration of trace amounts of benzene, toluene, ethylbenzene and xylene isomers in water samples followed by gas chromatographic analysis. Different parameters influencing the extraction efficiency of both methods such as type and volume of the extraction solvent and the disperser solvent; pH, temperature and volume of sample solution and ionic strength of samples were investigated and optimized. Under optimal condition, the limits of detection ranged from 1.7 to 2.4 µg L(-1) for IS-DLLME and 1.5 to 2.2 µg L(-1) for NB-DLLME. Precision (as relative standard deviation) of the two techniques was between 2.1 and 4.6% for IS-DLLME and between 1.5 and 4.5% for NB-DLLME. The enrichment factors found to be between 20-29 and 31-73 for IS- and NB-DLLME, respectively. The applicability of the proposed methods was investigated by analyzing real water samples. PMID:25595286

  20. Comparison of magnetic probe calibration at nano and millitesla magnitudes

    NASA Astrophysics Data System (ADS)

    Pahl, Ryan A.; Rovey, Joshua L.; Pommerenke, David J.

    2014-01-01

    Magnetic field probes are invaluable diagnostics for pulsed inductive plasma devices where field magnitudes on the order of tenths of tesla or larger are common. Typical methods of providing a broadband calibration of dot{{B}} probes involve either a Helmholtz coil driven by a function generator or a network analyzer. Both calibration methods typically produce field magnitudes of tens of microtesla or less, at least three and as many as six orders of magnitude lower than their intended use. This calibration factor is then assumed constant regardless of magnetic field magnitude and the effects of experimental setup are ignored. This work quantifies the variation in calibration factor observed when calibrating magnetic field probes in low field magnitudes. Calibration of two dot{{B}} probe designs as functions of frequency and field magnitude are presented. The first dot{{B}} probe design is the most commonly used design and is constructed from two hand-wound inductors in a differential configuration. The second probe uses surface mounted inductors in a differential configuration with balanced shielding to further reduce common mode noise. Calibration factors are determined experimentally using an 80.4 mm radius Helmholtz coil in two separate configurations over a frequency range of 100-1000 kHz. A conventional low magnitude calibration using a vector network analyzer produced a field magnitude of 158 nT and yielded calibration factors of 15 663 ± 1.7% and 4920 ± 0.6% {T}/{V {s}} at 457 kHz for the surface mounted and hand-wound probes, respectively. A relevant magnitude calibration using a pulsed-power setup with field magnitudes of 8.7-354 mT yielded calibration factors of 14 615 ± 0.3% and 4507 ± 0.4% {T}/{V {s}} at 457 kHz for the surface mounted inductor and hand-wound probe, respectively. Low-magnitude calibration resulted in a larger calibration factor, with an average difference of 9.7% for the surface mounted probe and 12.0% for the hand-wound probe. The maximum difference between relevant and low magnitude tests was 21.5%.

  1. Calibration of atmospheric hydrogen measurements

    NASA Astrophysics Data System (ADS)

    Jordan, A.; Steinberg, B.

    2011-03-01

    Interest in atmospheric hydrogen (H2) has been growing in recent years with the prospect of H2 being a potential alternative to fossil fuels as an energy carrier. This has intensified research for a quantitative understanding of the atmospheric hydrogen cycle and its total budget, including the expansion of the global atmospheric measurement network. However, inconsistencies in published observational data constitute a major limitation in exploring such data sets. The discrepancies can be mainly attributed to difficulties in the calibration of the measurements. In this study various factors that may interfere with accurate quantification of atmospheric H2 were investigated including drifts of standard gases in high pressure cylinders. As an experimental basis a procedure to generate precise mixtures of H2 within the atmospheric concentration range was established. Application of this method has enabled a thorough linearity characterization of the commonly used GC-HgO reduction detector. We discovered that the detector response was sensitive to the composition of the matrix gas. Addressing these systematic errors, a new calibration scale has been generated defined by thirteen standards with dry air mole fractions ranging from 139-1226 nmol mol-1. This new scale has been accepted as the official World Meteorological Organisation's (WMO) Global Atmospheric Watch (GAW) H2 mole fraction scale.

  2. Calibration of atmospheric hydrogen measurements

    NASA Astrophysics Data System (ADS)

    Jordan, A.; Steinberg, B.

    2010-11-01

    Interest in atmospheric hydrogen (H2) has been growing in recent years with the prospect of H2 being a potential alternative to fossil fuels as an energy carrier. This has intensified research for a quantitative understanding of the atmospheric hydrogen cycle and its total budget, including the expansion of the global atmospheric measurement network. However, inconsistencies in published observational data constitute a major limitation in exploring such data sets. The discrepancies can be mainly attributed to difficulties in the calibration of the measurements. In this study various factors that may interfere with accurate quantification of atmospheric H2 were investigated including drifts of standard gases in high pressure cylinders. As an experimental basis a procedure to generate precise mixtures of H2 within the atmospheric concentration range was established. Application of this method has enabled a thorough linearity characterization of the commonly used GC-HgO reduction detector. We discovered that the detector response was sensitive to the composition of the matrix gas. Addressing these systematic errors, an accurate calibration scale has been generated defined by thirteen standards with dry air mole fractions ranging from 139-1226 nmol mol-1. The new scale has been accepted as the official World Meteorological Organisation's (WMO) Global Atmospheric Watch (GAW) H2 mole fraction scale.

  3. Optical detector calibrator system

    NASA Technical Reports Server (NTRS)

    Strobel, James P. (Inventor); Moerk, John S. (Inventor); Youngquist, Robert C. (Inventor)

    1996-01-01

    An optical detector calibrator system simulates a source of optical radiation to which a detector to be calibrated is responsive. A light source selected to emit radiation in a range of wavelengths corresponding to the spectral signature of the source is disposed within a housing containing a microprocessor for controlling the light source and other system elements. An adjustable iris and a multiple aperture filter wheel are provided for controlling the intensity of radiation emitted from the housing by the light source to adjust the simulated distance between the light source and the detector to be calibrated. The geared iris has an aperture whose size is adjustable by means of a first stepper motor controlled by the microprocessor. The multiple aperture filter wheel contains neutral density filters of different attenuation levels which are selectively positioned in the path of the emitted radiation by a second stepper motor that is also controlled by the microprocessor. An operator can select a number of detector tests including range, maximum and minimum sensitivity, and basic functionality. During the range test, the geared iris and filter wheel are repeatedly adjusted by the microprocessor as necessary to simulate an incrementally increasing simulated source distance. A light source calibration subsystem is incorporated in the system which insures that the intensity of the light source is maintained at a constant level over time.

  4. Calibrating Distributed Camera Networks

    Microsoft Academic Search

    Dhanya Devarajan; Zhaolin Cheng; Richard J. Radke

    2008-01-01

    Recent developments in wireless sensor networks have made feasible distributed camera networks, in which cameras and processing nodes may be spread over a wide geographical area, with no centralized processor and limited ability to communicate a large amount of information over long distances. This paper overviews distributed algorithms for the calibration of such camera networks- that is, the automatic estimation

  5. Absolute fluorescence calibration

    NASA Astrophysics Data System (ADS)

    Young, I. T.; Garini, Y.; Vermolen, B.; Liqui Lung, G.; Brouwer, G.; Hendrichs, S.; el Morabit, M.; Spoelstra, J.; Wilhelm, E.; Zaal, M.

    2006-02-01

    While fluorescence microscope systems remains an essential tool in modern biology and medical work, no compact instrumentation has been developed for the rapid calibration of such systems. Almost invariably results are presented in terms of the [AU], "arbitrary units". To remedy this situation we have developed a small, portable instrument - the size of a microscope slide - that uses low-power LEDs at different wavelengths to produce calibrated amounts of light. A computer controls the instrument--through a USB connector--so that the current to the selected LED can be swept through an increasing range of values. The amount of light measured by the microscope's total imaging system (lenses, filters, EO sensor, and digitizer) is then recorded to provide a "current in, digital value out" calibration. Further, the current can be translated easily to optical power and thus photons per second at the chosen LED wavelength. We have built and programmed such a system, tested it for accuracy and precision, and used it to calibrate several microscopes and microscope/lens combinations. The results will be presented.

  6. Computerized tomography calibrator

    NASA Technical Reports Server (NTRS)

    Engel, Herbert P. (Inventor)

    1991-01-01

    A set of interchangeable pieces comprising a computerized tomography calibrator, and a method of use thereof, permits focusing of a computerized tomographic (CT) system. The interchangeable pieces include a plurality of nestable, generally planar mother rings, adapted for the receipt of planar inserts of predetermined sizes, and of predetermined material densities. The inserts further define openings therein for receipt of plural sub-inserts. All pieces are of known sizes and densities, permitting the assembling of different configurations of materials of known sizes and combinations of densities, for calibration (i.e., focusing) of a computerized tomographic system through variation of operating variables thereof. Rather than serving as a phanton, which is intended to be representative of a particular workpiece to be tested, the set of interchangeable pieces permits simple and easy standardized calibration of a CT system. The calibrator and its related method of use further includes use of air or of particular fluids for filling various openings, as part of a selected configuration of the set of pieces.

  7. Primer on multivariate calibration

    SciTech Connect

    Thomas, E.V. (Sandia National Lab., Albuquerque, NM (United States))

    1994-08-01

    In analytical chemistry, calibration is the procedure that relates instrumental measurements to an analyte of interest. Typically, instrumental measurements are obtained from specimens in which the amount (or level) of the analyte has been determined by some independent and inherently accurate assay (e.g., wet chemistry). Together, the instrumental measurements and results from the independent assays are used to construct a model that relates the analyte level to the instrumental measurements. The advent of high-speed digital computers has greatly increased data acquisition and analysis capabilities and has provided the analytical chemist with opportunities to use many measurements - perhaps hundreds - for calibrating an instrument (e.g., absorbances at multiple wave-lengths). To take advantage of this technology, however, new methods (i.e., multivariate calibration methods) were needed for analyzing and modeling the experimental data. The purpose of this report is to introduce several evolving multivariate calibration methods and to present some important issues regarding their use. 30 refs., 7 figs.

  8. Calibration loads for ALMA

    Microsoft Academic Search

    P. Yagoubov; A. Murk; R. Wylde; G. Bell; G. H. Tan

    2011-01-01

    This paper presents the design of the ALMA Calibration Loads based on the folded cone geometry. The design is supported by ray-tracing simulations of the multilayer absorber cones and comprehensive thermal analysis. Experimental verifications of the Loads' performance included reflection measurements between 30–700 GHz with a vector network analyzer and radiometric tests at different frequencies between 91 GHz and 700

  9. NVLAP calibration laboratory program

    SciTech Connect

    Cigler, J.L.

    1993-12-31

    This paper presents an overview of the progress up to April 1993 in the development of the Calibration Laboratories Accreditation Program within the framework of the National Voluntary Laboratory Accreditation Program (NVLAP) at the National Institute of Standards and Technology (NIST).

  10. The COS Calibration Pipeline

    Microsoft Academic Search

    Philip E. Hodge; M. E. Kaiser; C. D. Keyes; T. B. Ake; A. Aloisi; S. D. Friedman; C. M. Oliveira; B. Shaw; D. J. Sahnow; S. V. Penton; C. S. Froning; S. Beland; S. Osterman; J. Green; COS IDT

    2008-01-01

    The Cosmic Origins Spectrograph, COS, (Green, J, et al., 2000, Proc SPIE, 4013) will be installed in the Hubble Space Telescope (HST) during the next servicing mission. This will be the most sensitive ultraviolet spectrograph ever flown aboard HST. The program (CALCOS) for pipeline calibration of HST\\/COS data has been developed by the Space Telescope Science Institute. As with other

  11. Calibration procedure for Slocum glider deployed optical instruments.

    PubMed

    Cetini?, Ivona; Toro-Farmer, Gerardo; Ragan, Matthew; Oberg, Carl; Jones, Burton H

    2009-08-31

    Recent developments in the field of the autonomous underwater vehicles allow the wide usage of these platforms as part of scientific experiments, monitoring campaigns and more. The vehicles are often equipped with sensors measuring temperature, conductivity, chlorophyll a fluorescence (Chl a), colored dissolved organic matter (CDOM) fluorescence, phycoerithrin (PE) fluorescence and spectral volume scattering function at 117 degrees, providing users with high resolution, real time data. However, calibration of these instruments can be problematic. Most in situ calibrations are performed by deploying complementary instrument packages or water samplers in the proximity of the glider. Laboratory calibrations of the mounted sensors are difficult due to the placement of the instruments within the body of the vehicle. For the laboratory calibrations of the Slocum glider instruments we developed a small calibration chamber where we can perform precise calibrations of the optical instruments aboard our glider, as well as sensors from other deployment platforms. These procedures enable us to obtain pre- and post-deployment calibrations for optical fluorescence instruments, which may differ due to the biofouling and other physical damage that can occur during long-term glider deployments. We found that biofouling caused significant changes in the calibration scaling factors of fluorescent sensors, suggesting the need for consistent and repetitive calibrations for gliders as proposed in this paper. PMID:19724540

  12. Multivariate calibration applied to the quantitative analysis of infrared spectra

    SciTech Connect

    Haaland, D.M.

    1991-01-01

    Multivariate calibration methods are very useful for improving the precision, accuracy, and reliability of quantitative spectral analyses. Spectroscopists can more effectively use these sophisticated statistical tools if they have a qualitative understanding of the techniques involved. A qualitative picture of the factor analysis multivariate calibration methods of partial least squares (PLS) and principal component regression (PCR) is presented using infrared calibrations based upon spectra of phosphosilicate glass thin films on silicon wafers. Comparisons of the relative prediction abilities of four different multivariate calibration methods are given based on Monte Carlo simulations of spectral calibration and prediction data. The success of multivariate spectral calibrations is demonstrated for several quantitative infrared studies. The infrared absorption and emission spectra of thin-film dielectrics used in the manufacture of microelectronic devices demonstrate rapid, nondestructive at-line and in-situ analyses using PLS calibrations. Finally, the application of multivariate spectral calibrations to reagentless analysis of blood is presented. We have found that the determination of glucose in whole blood taken from diabetics can be precisely monitored from the PLS calibration of either mind- or near-infrared spectra of the blood. Progress toward the non-invasive determination of glucose levels in diabetics is an ultimate goal of this research. 13 refs., 4 figs.

  13. Simplified Vicarious Radiometric Calibration

    NASA Technical Reports Server (NTRS)

    Stanley, Thomas; Ryan, Robert; Holekamp, Kara; Pagnutti, Mary

    2010-01-01

    A measurement-based radiance estimation approach for vicarious radiometric calibration of spaceborne multispectral remote sensing systems has been developed. This simplified process eliminates the use of radiative transfer codes and reduces the number of atmospheric assumptions required to perform sensor calibrations. Like prior approaches, the simplified method involves the collection of ground truth data coincident with the overpass of the remote sensing system being calibrated, but this approach differs from the prior techniques in both the nature of the data collected and the manner in which the data are processed. In traditional vicarious radiometric calibration, ground truth data are gathered using ground-viewing spectroradiometers and one or more sun photometer( s), among other instruments, located at a ground target area. The measured data from the ground-based instruments are used in radiative transfer models to estimate the top-of-atmosphere (TOA) target radiances at the time of satellite overpass. These TOA radiances are compared with the satellite sensor readings to radiometrically calibrate the sensor. Traditional vicarious radiometric calibration methods require that an atmospheric model be defined such that the ground-based observations of solar transmission and diffuse-to-global ratios are in close agreement with the radiative transfer code estimation of these parameters. This process is labor-intensive and complex, and can be prone to errors. The errors can be compounded because of approximations in the model and inaccurate assumptions about the radiative coupling between the atmosphere and the terrain. The errors can increase the uncertainty of the TOA radiance estimates used to perform the radiometric calibration. In comparison, the simplified approach does not use atmospheric radiative transfer models and involves fewer assumptions concerning the radiative transfer properties of the atmosphere. This new technique uses two neighboring uniform ground target areas having different reflectance values. The target areas can be natural or artificial and must be large enough to minimize adjacent-pixel contamination effects. The radiative coupling between the atmosphere and the terrain needs to be approximately the same for the two targets. This condition can be met for relatively uniform backgrounds when the distance between the targets is within a few hundred meters. For each target area, the radiance leaving the ground in the direction of the satellite is measured with a radiometrically calibrated spectroradiometer. Using the radiance measurements from the two targets, atmospheric adjacency and atmospheric scattering effects can be subtracted, thereby eliminating many assumptions about the atmosphere and the radiative interaction between the atmosphere and the terrain. In addition, the radiometrically calibrated spectroradiometer can be used with a known reflectance target to estimate atmospheric transmission and diffuse- to-global ratios without the need for ancillary sun photometers. Several comparisons between the simplified method and traditional techniques were found to agree within a few percent. Hence, the simplified method reduces the overall complexity of performing vicarious calibrations and can serve as a method for validating traditional radiative transfer models

  14. Automated syringe sampler

    NASA Astrophysics Data System (ADS)

    Purgold, G. C.

    1981-06-01

    A number of sampling services are disposed in a rack which slides into a housing. In response to a signal from an antenna, the circutry elements are activated which provide power individually, collectively, or selectively to a servomechanism thereby moving an actuator arm and the attached jawed bracket supporting an evaculated tube towards a stationary needle. One open end of the needle extends through the side wall of a conduit to the interior and the other open end is maintained within the protective sleeve, supported by a bifurcated bracket. A septum in punctured by the end of the needle within the sleeve and a sample of the fluid medium in the conduit flows through the needle and is transferred to a tube. The signal to the servo is then reversed and the actuator arm moves the tube back to its original position permitting the septum to expand and seal the hole made by the needle. The jawed bracket is attached by pivot to the actuator to facilitate tube replacement.

  15. Polarimetric SAR calibration experiment using active radar calibrators

    Microsoft Academic Search

    Anthony Freeman; Yuhsyen Shen; C. L. Werner

    1990-01-01

    Active radar calibrators are used to derive both the amplitude and phase characteristics of a multichannel polarimetric synthetic aperture radar (SAR) from the complex image data. Results are presented from an experiment carried out using the NASA\\/JPL DC-8 aircraft SAR over a calibration site at Goldstone, California. As part of the experiment, polarimetric active radar calibrators (PARCs) with adjustable polarization

  16. New approach to calibrating bed load samplers ( calibration curves).

    USGS Publications Warehouse

    Hubbell, D.W.; Stevens, H.H.; Skinner, J.V.

    1985-01-01

    Calibration curves are derived by two independent methods using data collected with prototype versions of the Helley-Smith sampler in a large calibration facility capable of continuously measuring transport rates across a 9ft (2.7m) width. Results from both methods agree. Composite calibration curves are obtained for six different versions of the sampler.-from ASCE Publications Information

  17. Mercury CEM Calibration

    SciTech Connect

    John F. Schabron; Joseph F. Rovani; Susan S. Sorini

    2007-03-31

    The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005, requires that calibration of mercury continuous emissions monitors (CEMs) be performed with NIST-traceable standards. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor generators. The traceability protocol will be written by EPA. Traceability will be based on the actual analysis of the output of each calibration unit at several concentration levels ranging from about 2-40 ug/m{sup 3}, and this analysis will be directly traceable to analyses by NIST using isotope dilution inductively coupled plasma/mass spectrometry (ID ICP/MS) through a chain of analyses linking the calibration unit in the power plant to the NIST ID ICP/MS. Prior to this project, NIST did not provide a recommended mercury vapor pressure equation or list mercury vapor pressure in its vapor pressure database. The NIST Physical and Chemical Properties Division in Boulder, Colorado was subcontracted under this project to study the issue in detail and to recommend a mercury vapor pressure equation that the vendors of mercury vapor pressure calibration units can use to calculate the elemental mercury vapor concentration in an equilibrium chamber at a particular temperature. As part of this study, a preliminary evaluation of calibration units from five vendors was made. The work was performed by NIST in Gaithersburg, MD and Joe Rovani from WRI who traveled to NIST as a Visiting Scientist.

  18. Ability to access community-based needle-syringe programs and injecting behaviors among drug users: a cross-sectional study in Hunan Province, China

    PubMed Central

    2013-01-01

    Background Needle-syringe exchange programs (NSPs) have been substantially rolled-out in China since 2002. Limited studies reported effectiveness of NSPs in a Chinese setting. This study aimed to assess the association between accessibility to NSPs and drug-use risk behaviors of IDUs by investigating primary (self-reported) data of IDUs recruited from NSP sites, community settings and mandatory detoxification centers (MDCs) in Hunan province, China. Methods A cross-sectional survey was conducted in Hunan province in 2010. IDU recruits participated in a face-to-face interview to provide information related to their ability to access NSPs, demographic characteristics, and injecting behaviors in the past 30 days. Results Of the total 402 participants, 35%, 14% and 51% participants indicated low, medium and high ability to access NSPs in the past 30 days, respectively. A significantly higher proportion of IDUs (77.3%) from the high-access group reported ?2 injecting episodes per day compared with medium- (46.3%) and low-access (58.8%) groups. Only 29.0% of high-access IDUs re-used syringes before disposal in the past 30 days, significantly lower than those in the medium- (43.1%) and low-access (41.3%) groups. Reported levels of needle/syringe sharing decreased significantly as the ability to access NSPs increased (16.3%, 12.7% and 2.5% in the low, medium and high access groups, respectively). Ninety percent of IDUs recruited from MDCs had low ability to access NSPs. Conclusions Increased NSP accessibility is associated with decreased levels of injecting frequency, repetitive use and sharing of injecting equipment among Chinese IDUs. Mandatory detention of IDUs remains as a major barrier for IDUs to access NSPs in China. PMID:23651665

  19. Novel one-step headspace dynamic in-syringe liquid phase derivatization-extraction technique for the determination of aqueous aliphatic amines by liquid chromatography with fluorescence detection.

    PubMed

    Muniraj, Sarangapani; Shih, Hou-Kung; Chen, Ying-Fang; Hsiech, Chunming; Ponnusamy, Vinoth Kumar; Jen, Jen-Fon

    2013-06-28

    A novel one-step headspace (HS) dynamic in-syringe (DIS) based liquid-phase derivatization-extraction (LPDE) technique has been developed for the selective determination of two short-chain aliphatic amines (SCAAs) in aqueous samples using high performance liquid chromatography (HPLC) with fluorescence detection (FLD). Methylamine (MA) and dimethylamine (DMA) were selected as model compounds of SCAAs. In this method, a micro-syringe pre-filled with derivatizing reagent solution (9-fluorenylmethyl chloroformate) in the barrel was applied to achieve the simultaneous derivatization and extraction of two methylamines evolved from alkalized aqueous samples through the automated reciprocated movements of syringe plunger. After the derivatization-extraction process, the derivatized phase was directly injected into HPLC-FLD for analysis. Parameters influencing the evolution of methylamines and the HS-DIS-LPDE efficiency, including sample pH and temperature, sampling time, as well as the composition of derivatization reagent, reaction temperature, and frequency of reciprocated plunger movements, were thoroughly examined and optimized. Under optimal conditions, detections were linear in the range of 25-500?gL(-1) for MA and DMA with correlation coefficients all above 0.995. The limits of detection (based on S/N=3) were 5 and 19ngmL(-1) for MA and DMA, respectively. The applicability of the developed method was demonstrated for the determination of MA and DMA in real water samples without any prior cleanup of the sample. The present method provides a simple, selective, automated, low cost and eco-friendly procedure to determine aliphatic amines in aqueous samples. PMID:23591526

  20. An improved procedure for developing a calibrated hourly simulation model of an electrically heated and cooled commercial building

    E-print Network

    Bou-Saada, Tarek Edmond

    1994-01-01

    With the increased use of building energy simulation programs, calibration of simulated data to measured data has been recognized as an important factor in substantiating how well the model fits a real building. Model calibration to measured monthly...

  1. Absolute radiometric calibration of Landsat using a pseudo invariant calibration site

    USGS Publications Warehouse

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

    2013-01-01

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

  2. Reference-cell calibration activities

    Microsoft Academic Search

    R. Mueller

    1984-01-01

    The use of secondary calibration in large area pulsed solar simulators (LAPSS) is discussed. It is argued that primary calibration in sunlight is time consuming, that only a limited sun calibration of a set of primary reference cells is required, that the LAPSS light source is filtered to closely match the am 1.5 direct spectrum, and that the temperal stability

  3. Internet-Based Calibration of a Multifunction Calibrator

    SciTech Connect

    BUNTING BACA,LISA A.; DUDA JR.,LEONARD E.; WALKER,RUSSELL M.; OLDHAM,NILE; PARKER,MARK

    2000-12-19

    A new way of providing calibration services is evolving which employs the Internet to expand present capabilities and make the calibration process more interactive. Sandia National Laboratories and the National Institute of Standards and Technology are collaborating to set up and demonstrate a remote calibration of multijunction calibrators using this Internet-based technique that is becoming known as e-calibration. This paper describes the measurement philosophy and the Internet resources that can provide real-time audio/video/data exchange, consultation and training, as well as web-accessible test procedures, software and calibration reports. The communication system utilizes commercial hardware and software that should be easy to integrate into most calibration laboratories.

  4. Internet-based calibration of a multifunction calibrator

    SciTech Connect

    BUNTING BACA,LISA A.; DUDA JR.,LEONARD E.; WALKER,RUSSELL M.; OLDHAM,NILE; PARKER,MARK

    2000-04-17

    A new way of providing calibration services is evolving which employs the Internet to expand present capabilities and make the calibration process more interactive. Sandia National Laboratories and the National Institute of Standards and Technology are collaborating to set up and demonstrate a remote calibration of multifunction calibrators using this Internet-based technique that is becoming known as e-calibration. This paper describes the measurement philosophy and the Internet resources that can provide real-time audio/video/data exchange, consultation and training, as well as web-accessible test procedures, software and calibration reports. The communication system utilizes commercial hardware and software that should be easy to integrate into most calibration laboratories.

  5. Calibrating pressure switch

    NASA Technical Reports Server (NTRS)

    Smith, N. J. (inventor)

    1968-01-01

    A pressure switch assembly comprising a body portion and a switch mechanism having a contact element operable between opposite limit positions is described. A diaphragm chamber is provided in the body portion which mounts therein a system diaphragm and a calibration diaphragm which are of generally the same configuration and having outer faces conforming to the inner and outer walls of the diaphragm chamber. The space between the inner faces of the diaphragms defines a first chamber section and the space between the outer face of one of the diaphragms and the outer wall of the diaphragm chamber defines a second chamber section. The body portion includes a system pressure port communicating with one of the chamber sections and a calibration pressure port communicating with the other chamber section. An actuator connected to one of the diaphragms and the contact element of the switch operates upon pressure change in the diaphragm sections to move said contact element between limit positions.

  6. Calibrated vapor generator source

    SciTech Connect

    Davies, J.P.; Larson, R.A.; Goodrich, L.D.; Hall, H.J.; Stoddard, B.D.; Davis, S.G.; Kaser, T.G.; Conrad, F.J.

    1995-09-26

    A portable vapor generator is disclosed that can provide a controlled source of chemical vapors, such as, narcotic or explosive vapors. This source can be used to test and calibrate various types of vapor detection systems by providing a known amount of vapors to the system. The vapor generator is calibrated using a reference ion mobility spectrometer. A method of providing this vapor is described, as follows: explosive or narcotic is deposited on quartz wool, placed in a chamber that can be heated or cooled (depending on the vapor pressure of the material) to control the concentration of vapors in the reservoir. A controlled flow of air is pulsed over the quartz wool releasing a preset quantity of vapors at the outlet. 10 figs.

  7. Multivariate Regression with Calibration*

    PubMed Central

    Liu, Han; Wang, Lie; Zhao, Tuo

    2014-01-01

    We propose a new method named calibrated multivariate regression (CMR) for fitting high dimensional multivariate regression models. Compared to existing methods, CMR calibrates the regularization for each regression task with respect to its noise level so that it is simultaneously tuning insensitive and achieves an improved finite-sample performance. Computationally, we develop an efficient smoothed proximal gradient algorithm which has a worst-case iteration complexity O(1/?), where ? is a pre-specified numerical accuracy. Theoretically, we prove that CMR achieves the optimal rate of convergence in parameter estimation. We illustrate the usefulness of CMR by thorough numerical simulations and show that CMR consistently outperforms other high dimensional multivariate regression methods. We also apply CMR on a brain activity prediction problem and find that CMR is as competitive as the handcrafted model created by human experts. PMID:25620861

  8. MIRO Calibration Switch Mechanism

    NASA Technical Reports Server (NTRS)

    Suchman, Jason; Salinas, Yuki; Kubo, Holly

    2001-01-01

    The Jet Propulsion Laboratory has designed, analyzed, built, and tested a calibration switch mechanism for the MIRO instrument on the ROSETTA spacecraft. MIRO is the Microwave Instrument for the Rosetta Orbiter; this instrument hopes to investigate the origin of the solar system by studying the origin of comets. Specifically, the instrument will be the first to use submillimeter and millimeter wave heterodyne receivers to remotely examine the P-54 Wirtanen comet. In order to calibrate the instrument, it needs to view a hot and cold target. The purpose of the mechanism is to divert the instrument's field of view from the hot target, to the cold target, and then back into space. This cycle is to be repeated every 30 minutes for the duration of the 1.5 year mission. The paper describes the development of the mechanism, as well as analysis and testing techniques.

  9. SOFIE instrument ground calibration

    NASA Astrophysics Data System (ADS)

    Hansen, Scott; Fish, Chad; Romrell, Devin; Gordley, Larry; Hervig, Mark

    2006-08-01

    Space Dynamics Laboratory (SDL), in partnership with GATS, Inc., designed and built an instrument to conduct the Solar Occultation for Ice Experiment (SOFIE). SOFIE is the primary infrared sensor in the NASA Aeronomy of Ice in the Mesosphere (AIM) instrument suite. AIM's mission is to study polar mesospheric clouds (PMCs). SOFIE will make measurements in 16 separate spectral bands, arranged in eight pairs between 0.29 and 5.3 ?m. Each band pair will provide differential absorption limb-path transmission profiles for an atmospheric component of interest, by observing the sun through the limb of the atmosphere during solar occultation as AIM orbits Earth. A pointing mirror and imaging sun sensor coaligned with the detectors are used to track the sun during occultation events and maintain stable alignment of the sun on the detectors. Ground calibration experiments were performed to measure SOFIE end-to-end relative spectral response, nonlinearity, and spatial characteristics. SDL's multifunction infrared calibrator #1 (MIC1) was used to present sources to the instrument for calibration. Relative spectral response (RSR) measurements were performed using a step-scan Fourier transform spectrometer (FTS). Out-of-band RSR was measured to approximately 0.01% of in-band peak response using the cascaded filter Fourier transform spectrometer (CFFTS) method. Linearity calibration was performed using a calcium fluoride attenuator in combination with a 3000K blackbody. Spatial characterization was accomplished using a point source and the MIC1 pointing mirror. SOFIE sun sensor tracking algorithms were verified using a heliostat and relay mirrors to observe the sun from the ground. These techniques are described in detail, and resulting SOFIE performance parameters are presented.

  10. Optical Calibration of SNO+

    NASA Astrophysics Data System (ADS)

    Maneira, J.; Peeters, S.; Sinclair, J.

    2015-04-01

    SNO is being upgraded to SNO+, which has as its main goal the search for neutrinoless double-beta decay. The upgrade is defined by filling with a novel scintillator mixture containing 130Te. With a lower energy threshold than SNO, SNO+ will be sensitive to other exciting new physics. Here we are describing new optical calibration system that meets new, more stringent radiopurity requirements has been developed.

  11. Calibration of hydrometers

    NASA Astrophysics Data System (ADS)

    Lorefice, Salvatore; Malengo, Andrea

    2006-10-01

    After a brief description of the different methods employed in periodic calibration of hydrometers used in most cases to measure the density of liquids in the range between 500 kg m-3 and 2000 kg m-3, particular emphasis is given to the multipoint procedure based on hydrostatic weighing, known as well as Cuckow's method. The features of the calibration apparatus and the procedure used at the INRiM (formerly IMGC-CNR) density laboratory have been considered to assess all relevant contributions involved in the calibration of different kinds of hydrometers. The uncertainty is strongly dependent on the kind of hydrometer; in particular, the results highlight the importance of the density of the reference buoyant liquid, the temperature of calibration and the skill of operator in the reading of the scale in the whole assessment of the uncertainty. It is also interesting to realize that for high-resolution hydrometers (division of 0.1 kg m-3), the uncertainty contribution of the density of the reference liquid is the main source of the total uncertainty, but its importance falls under about 50% for hydrometers with a division of 0.5 kg m-3 and becomes somewhat negligible for hydrometers with a division of 1 kg m-3, for which the reading uncertainty is the predominant part of the total uncertainty. At present the best INRiM result is obtained with commercially available hydrometers having a scale division of 0.1 kg m-3, for which the relative uncertainty is about 12 × 10-6.

  12. Calibrated Properties Model

    SciTech Connect

    H. H. Liu

    2003-02-14

    This report has documented the methodologies and the data used for developing rock property sets for three infiltration maps. Model calibration is necessary to obtain parameter values appropriate for the scale of the process being modeled. Although some hydrogeologic property data (prior information) are available, these data cannot be directly used to predict flow and transport processes because they were measured on scales smaller than those characterizing property distributions in models used for the prediction. Since model calibrations were done directly on the scales of interest, the upscaling issue was automatically considered. On the other hand, joint use of data and the prior information in inversions can further increase the reliability of the developed parameters compared with those for the prior information. Rock parameter sets were developed for both the mountain and drift scales because of the scale-dependent behavior of fracture permeability. Note that these parameter sets, except those for faults, were determined using the 1-D simulations. Therefore, they cannot be directly used for modeling lateral flow because of perched water in the unsaturated zone (UZ) of Yucca Mountain. Further calibration may be needed for two- and three-dimensional modeling studies. As discussed above in Section 6.4, uncertainties for these calibrated properties are difficult to accurately determine, because of the inaccuracy of simplified methods for this complex problem or the extremely large computational expense of more rigorous methods. One estimate of uncertainty that may be useful to investigators using these properties is the uncertainty used for the prior information. In most cases, the inversions did not change the properties very much with respect to the prior information. The Output DTNs (including the input and output files for all runs) from this study are given in Section 9.4.

  13. The NICMOS Polarimetric Calibration

    E-print Network

    D. Batcheldor; A. Robinson; D. Axon; D. C. Hines; W. Sparks; C. Tadhunter

    2006-01-24

    The value of accurately knowing the absolute calibration of the polarizing elements in the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) becomes especially important when conducting studies which require measuring degrees of polarization of close to 1% in the near infrared. We present a comprehensive study of all previously observed polarimetric standards using the NIC2 camera on NICMOS. Considering both pre- and post-NICMOS Cooling System observations we find variations in the polarimetry consistent with the effects of sub-pixel mis-alignments and the point spread function. We also measure non-zero results from unpolarized standards indicating an instrumental polarization of p ~ 1.2%, theta ~ 88degrees. The lack of polarized and unpolarized standard stars with which to perform a comprehensive calibration study means we cannot be confident that the current calibration will be effective for a number of recent large NICMOS GO programs. Further observations of polarimetric standards are needed in order to fully characterize the behavior of NICMOS at around p=1%.

  14. Calibrated Properties Model

    SciTech Connect

    T. Ghezzehej

    2004-10-04

    The purpose of this model report is to document the calibrated properties model that provides calibrated property sets for unsaturated zone (UZ) flow and transport process models (UZ models). The calibration of the property sets is performed through inverse modeling. This work followed, and was planned in, ''Technical Work Plan (TWP) for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Sections 1.2.6 and 2.1.1.6). Direct inputs to this model report were derived from the following upstream analysis and model reports: ''Analysis of Hydrologic Properties Data'' (BSC 2004 [DIRS 170038]); ''Development of Numerical Grids for UZ Flow and Transport Modeling'' (BSC 2004 [DIRS 169855]); ''Simulation of Net Infiltration for Present-Day and Potential Future Climates'' (BSC 2004 [DIRS 170007]); ''Geologic Framework Model'' (GFM2000) (BSC 2004 [DIRS 170029]). Additionally, this model report incorporates errata of the previous version and closure of the Key Technical Issue agreement TSPAI 3.26 (Section 6.2.2 and Appendix B), and it is revised for improved transparency.

  15. Persistence and Change in Disparities in HIV Infection Among Injection Drug Users in New York City After Large-Scale Syringe Exchange Programs

    PubMed Central

    Des Jarlais, Don C.; Arasteh, Kamyar; Hagan, Holly; McKnight, Courtney; Perlman, David C.; Friedman, Samuel R.

    2015-01-01

    Objectives We examined racial/ethnic disparities in HIV infection among injection drug users (IDUs) before and after implementation of large-scale syringe exchange programs in New York City. Methods Participants were recruited from IDUs entering the Beth Israel drug detoxification program in New York City. Participants (n=1203) recruited from 1990 through 1994, prior to large-scale syringe exchange programs (pre-exchange), were compared with 1109 participants who began injecting in 1995 or later and were interviewed in 1995 through 2008 (post-exchange). Results There were large differences in HIV prevalence among pre-exchange vs post-exchange participants (African Americans, 57% vs 15%; Hispanics, 53% vs 5%; Whites, 27% vs 3%). Pre-and post-exchange relative disparities of HIV prevalence were similar for African Americans vs Whites (adjusted odds ratio [AOR]=3.46, 95% confidence interval [CI]=2.41, 4.96 and AOR=4.02, 95% CI=1.67, 9.69, respectively) and Hispanics vs Whites (AOR=1.76, 95% CI=1.49, 2.09 and AOR=1.49, 95% CI=1.02, 2.17). Racial/ethnic group differences in risk behavior did not explain differences in HIV prevalence. Conclusions New interventions are needed to address continuing disparities in HIV infection among IDUs, but self-reported risk behaviors by themselves may not be adequate outcome measures for evaluating interventions to reduce racial/ethnic disparities in HIV infection. PMID:19797757

  16. Computer-aided calibration: Asking the right questions

    SciTech Connect

    Turvill, I.H. [Rochester Instrument Systems, Inc., NY (United States)

    1995-12-01

    Anyone involved with instrumentation and control would find it hard to avoid the ever-increasing promotion of calibrators. Calibrators and calibration are everywhere: in magazines, at trade shows, in ISO 9000 audits, and in instrument technician`s shops. The growth in this market is screamingly obvious. However, changes in the market for calibrators are not limited to increased demand for these products. Today`s trends emerge from several root causes. These include shifts in customer preference and behavior, changing relationships between firms involved in the different stages of the chain that supplies customers, and exogenous factors such as stricter government regulations and tighter industrial standards. In recent years, the United States federal government, through its Environmental Protection Agency (EPA), has placed increasing demands on {open_quotes}smokestack{close_quotes} industries to demonstrate effective monitoring of pollutants. The Food and Drug Administration (FDA) requires that all pharmaceutical companies validate their manufacturing processes. Many manufacturers recognize that the industries they serve are faced with increasing demand for instrument recalibration and documentation with decreasing maintenance resources. In response to the need for systems that can square the circle, manufacturers have introduced computer-aided calibration (CAC) systems that automatically execute calibration procedures and collect test and calibration data, which significantly improves productivity. The array of such systems now available is staggering. In certain instances, suppliers offer only hardware, such as calibrators, sources, and simulators that can communicate with a software package. Some software houses offer universal calibration packages, which can communicate with a wide variety of calibrators, or none. Others, usually hardware manufacturers, offer complete packages that consist of a calibrator and proprietary software.

  17. Self-Calibrating Pressure Transducer

    NASA Technical Reports Server (NTRS)

    Lueck, Dale E. (Inventor)

    2006-01-01

    A self-calibrating pressure transducer is disclosed. The device uses an embedded zirconia membrane which pumps a determined quantity of oxygen into the device. The associated pressure can be determined, and thus, the transducer pressure readings can be calibrated. The zirconia membrane obtains oxygen .from the surrounding environment when possible. Otherwise, an oxygen reservoir or other source is utilized. In another embodiment, a reversible fuel cell assembly is used to pump oxygen and hydrogen into the system. Since a known amount of gas is pumped across the cell, the pressure produced can be determined, and thus, the device can be calibrated. An isolation valve system is used to allow the device to be calibrated in situ. Calibration is optionally automated so that calibration can be continuously monitored. The device is preferably a fully integrated MEMS device. Since the device can be calibrated without removing it from the process, reductions in costs and down time are realized.

  18. Automatic force balance calibration system

    NASA Technical Reports Server (NTRS)

    Ferris, Alice T. (Inventor)

    1996-01-01

    A system for automatically calibrating force balances is provided. The invention uses a reference balance aligned with the balance being calibrated to provide superior accuracy while minimizing the time required to complete the calibration. The reference balance and the test balance are rigidly attached together with closely aligned moment centers. Loads placed on the system equally effect each balance, and the differences in the readings of the two balances can be used to generate the calibration matrix for the test balance. Since the accuracy of the test calibration is determined by the accuracy of the reference balance and current technology allows for reference balances to be calibrated to within .+-.0.05%, the entire system has an accuracy of a .+-.0.2%. The entire apparatus is relatively small and can be mounted on a movable base for easy transport between test locations. The system can also accept a wide variety of reference balances, thus allowing calibration under diverse load and size requirements.

  19. In-situ Broadband Cryogenic Calibration for Two-port Superconducting Microwave Resonators

    E-print Network

    Jen-Hao Yeh; Steven M. Anlage

    2013-03-10

    We introduce an improved microwave calibration method for use in a cryogenic environment, based on a traditional three-standard calibration, the Thru-Reflect-Line (TRL) calibration. The modified calibration method takes advantage of additional information from multiple measurements of an ensemble of realizations of a superconducting resonator, as a new pseudo-Open standard, to correct errors in the TRL calibration. We also demonstrate an experimental realization of this in-situ broadband cryogenic calibration system utilizing cryogenic switches. All calibration measurements are done in the same thermal cycle as the measurement of the resonator (requiring only an additional 20 minutes), thus avoiding 4 additional thermal cycles for traditional TRL calibration (which would require an additional 12 days). The experimental measurements on a wave-chaotic microwave billiard verify that the new method significantly improves the measured scattering matrix of a high-quality-factor superconducting resonator.

  20. In situ broadband cryogenic calibration for two-port superconducting microwave resonators

    SciTech Connect

    Yeh, Jen-Hao; Anlage, Steven M. [Electrical and Computer Engineering Department, University of Maryland, College Park, Maryland 20742-3285 (United States); CNAM, Physics Department, University of Maryland, College Park, Maryland 20742-4111 (United States)

    2013-03-15

    We introduce an improved microwave calibration method for use in a cryogenic environment, based on a traditional three-standard calibration, the Thru-Reflect-Line (TRL) calibration. The modified calibration method takes advantage of additional information from multiple measurements of an ensemble of realizations of a superconducting resonator, as a new pseudo-Open standard, to correct errors in the TRL calibration. We also demonstrate an experimental realization of this in situ broadband cryogenic calibration system utilizing cryogenic switches. All calibration measurements are done in the same thermal cycle as the measurement of the resonator (requiring only an additional 20 min), thus avoiding 4 additional thermal cycles for traditional TRL calibration (which would require an additional 12 days). The experimental measurements on a wave-chaotic microwave billiard verify that the new method significantly improves the measured scattering matrix of a high-quality-factor superconducting resonator.

  1. Method calibration of the model 13145 infrared target projectors

    NASA Astrophysics Data System (ADS)

    Huang, Jianxia; Gao, Yuan; Han, Ying

    2014-11-01

    The SBIR Model 13145 Infrared Target Projectors ( The following abbreviation Evaluation Unit ) used for characterizing the performances of infrared imaging system. Test items: SiTF, MTF, NETD, MRTD, MDTD, NPS. Infrared target projectors includes two area blackbodies, a 12 position target wheel, all reflective collimator. It provide high spatial frequency differential targets, Precision differential targets imaged by infrared imaging system. And by photoelectricity convert on simulate signal or digital signal. Applications software (IR Windows TM 2001) evaluate characterizing the performances of infrared imaging system. With regards to as a whole calibration, first differently calibration for distributed component , According to calibration specification for area blackbody to calibration area blackbody, by means of to amend error factor to calibration of all reflective collimator, radiance calibration of an infrared target projectors using the SR5000 spectral radiometer, and to analyze systematic error. With regards to as parameter of infrared imaging system, need to integrate evaluation method. According to regulation with -GJB2340-1995 General specification for military thermal imaging sets -testing parameters of infrared imaging system, the results compare with results from Optical Calibration Testing Laboratory . As a goal to real calibration performances of the Evaluation Unit.

  2. Sparsity-Promoting Calibration for GRAPPA Accelerated Parallel MRI Reconstruction

    PubMed Central

    Weller, Daniel S.; Polimeni, Jonathan R.; Grady, Leo; Wald, Lawrence L.; Adalsteinsson, Elfar; Goyal, Vivek K

    2013-01-01

    The amount of calibration data needed to produce images of adequate quality can prevent auto-calibrating parallel imaging reconstruction methods like Generalized Autocalibrating Partially Parallel Acquisitions (GRAPPA) from achieving a high total acceleration factor. To improve the quality of calibration when the number of auto-calibration signal (ACS) lines is restricted, we propose a sparsity-promoting regularized calibration method that finds a GRAPPA kernel consistent with the ACS fit equations that yields jointly sparse reconstructed coil channel images. Several experiments evaluate the performance of the proposed method relative to un-regularized and existing regularized calibration methods for both low-quality and underdetermined fits from the ACS lines. These experiments demonstrate that the proposed method, like other regularization methods, is capable of mitigating noise amplification, and in addition, the proposed method is particularly effective at minimizing coherent aliasing artifacts caused by poor kernel calibration in real data. Using the proposed method, we can increase the total achievable acceleration while reducing degradation of the reconstructed image better than existing regularized calibration methods. PMID:23584259

  3. The Calibration of the DD Neutron Indium Activation Diagnostic

    NASA Astrophysics Data System (ADS)

    Song, Zifeng; Chen, Jiabin; Liu, Zhongjie; Zhan, Xiayu; Tang, Qi

    2015-04-01

    The indium activation diagnostic was calibrated using an accelerator neutron source to facilitate the diagnosis of deuterium-deuterium (DD) neutron yields of implosion experiments in the Shenguang-III facility. The scattered neutron background of the accelerator room was measured by placing a polypropylene shadow bar in front of the indium sample, so as to correct the calibrated factor of this activation diagnostic. The proper size of the shadow bar was given by Monte Carlo simulation. The calibration results showed that the scattered neutron background of the accelerator room was about 9% of the incident neutrons on the sample. Subtracting the portion induced by the neutron background, the calibrated factor for this sample condition was 4.52×10?7 counts/n with an uncertainty of 4.3%.

  4. Sprayer Calibration for Turfgrass

    E-print Network

    Taylor, Gene R.; Abernathy, Scott

    1999-12-08

    system and nozzles. Calibrate sprayers every fourth application. Before any spraying operation, make a visual check of the spraying unit. Make sure all equipment is in working order and that there are no leaks in hoses or connections. VISUAL inspection... boom and check for leaks in the hoses that lead to the boom, the nozzle hoses and the nozzle assemblies. 6. Visually check the spray pattern from each nozzle. If a nozzle has an improper spray pattern, replace it with a new one of the same style...

  5. Calibration and Alignment.

    NASA Astrophysics Data System (ADS)

    Grassotti, Christopher; Iskenderian, Haig; Hoffman, Ross N.

    1999-06-01

    Discrepancies between estimates of rainfall from ground-based radar and satellite observing systems can be attributed to either calibration differences or to geolocation and sampling differences. These latter include differences due to radar or satellite misregistration, differences in observation times, or variations in instrument and retrieval algorithm sensitivities. A new methodology has been developed and tested for integrating radar- and satellite-based estimates of precipitation using a feature calibration and alignment (FCA) technique. The parameters describing the calibration and alignment are found using a variational approach, and are composed of displacement and amplitude adjustments to the satellite rainfall retrievals, which minimize the differences with respect to the radar data and satisfy additional smoothness and magnitude constraints. In this approach the amplitude component represents a calibration of the satellite estimate to the radar, whereas the displacement components correct temporal and/or geolocation differences between the radar and satellite data.The method has been tested on a number of cases of the NASA WetNet PIP-2 dataset. These data consist of coincident estimates of rainfall by ground-based radar and the DMSP SSM/I. Sensitivity tests were conducted to tune the parameters of the algorithm. Results indicate the effectiveness of the technique in minimizing the discrepancies between radar and satellite observations of rainfall for a variety of rainfall events ranging from midlatitude frontal precipitation to heavy convection associated with a tropical cyclone (Hurricane Andrew). A remaining issue to be resolved is the incorporation of knowledge about location dependencies in the errors of the radar and microwave estimates.Once the satellite data have been adjusted to match the radar observations, the two independent estimates (radar and adjusted SSM/I rain rates) may be blended to improve the overall depiction of the rainfall event in a single analysis. The FCA technique also has potential applications in 1) the development of satellite rainfall retrieval algorithms that may be tuned to radar rain rates and 2) error assessment of rainfall predictions using radar or satellite rain rates as verification.

  6. An Overview of MODIS Calibration and Characterization

    NASA Technical Reports Server (NTRS)

    Xiong, X.; Barnes, W.

    2004-01-01

    The MODerate Resolution Imaging Spectroradiometer (MODIS) is one of the key instruments for the NASA s Earth Observing System (EOS). It is currently operating on both EOS Terra and Aqua satellites. The MODIS is a major advance over its heritage sensors in terms of its spectral, spatial, and temporal resolutions with frequent global observations and a broad range of science applications. There are 20 reflective solar bands (RSB) with center wavelengths ranging from 0.41 to 2.l microns and 16 thermal emissive bands (TEB) from 3.7 to 14.4 microns. The absolute radiometric accuracy requirements (lsigma) at the typical spectral radiance levels are plus or minus 2% for the RSB reflectance factors and plus or minus 5% for the RSB radiance products. With few exceptions, the TEB requirements are plus or minus 1%. To verify that the instruments met their specified design requirements both Terra and Aqua MODIS underwent extensive pre-launch calibration and characterization at various levels, including system-level thermal vacuum testing. On-orbit calibration and characterization are performed by the on-board calibrators: a solar diffuser (SD) and a solar diffuser stability monitor (SDSM), a V-groove flat panel blackbody (BB), and a spectro-radiometric calibration assembly (SRCA). In this paper, we present an overview of MODIS calibration and characterization activities, methodologies, and lessons learned from pre-launch testing and on-orbit operations. Key issues to be discussed include our on-orbit efforts of monitoring detectors noise characterization, tracking solar diffuser and optics degradation, and updating sensor s response versus scan-angle. The MODIS experience has provided invaluable lessons that are being used in designing and testing the Visible Infrared Imaging Radiometer Suite (VIIRS), a direct follow-on to the MODIS that will be flown on the National Polar-Orbit Operational Environmental Satellite System (NPOESS) missions.

  7. Optical calibration of SNO +

    NASA Astrophysics Data System (ADS)

    Leming, Edward; SNO+ Collaboration

    2015-04-01

    Situated 2 km underground in Sudbury, Northern Ontario, the SNO + detector consists of an acrylic sphere 12 m in diameter containing 780 tons of target mass, surrounded by approximately 9,500 PMTs. For SNO, this target mass was heavy water, however the change to SNO + is defined by the change of this target mass to a novel scintillator. With the lower energy threshold, low intrinsic radioactivity levels and the best shielding against muons and cosmogenic activation of all existing neutrino experiments, SNO + will be sensitive to exciting new physics. The experiment will be studying solar, reactor, super nova and geo-neutrinos, though the main purpose of SNO + is the search for neutrinoless double-beta decay of Te-130. To meet the requirements imposed by the physics on detector performance, a detailed optical calibration is needed. Source deployment must be kept to a minimum and eliminated if possible, in order to meet the stringent radiopurity requirements. This led to the development of the Embedded LED/laser Light Injection Entity (ELLIE) system. This talk provides a summary of the upgrades to from SNO to SNO +, discussing the requirements on and methods of optical calibration, focusing on the deployed laserball and ELLIE system.

  8. Neural networks for calibration tomography

    NASA Technical Reports Server (NTRS)

    Decker, Arthur

    1993-01-01

    Artificial neural networks are suitable for performing pattern-to-pattern calibrations. These calibrations are potentially useful for facilities operations in aeronautics, the control of optical alignment, and the like. Computed tomography is compared with neural net calibration tomography for estimating density from its x-ray transform. X-ray transforms are measured, for example, in diffuse-illumination, holographic interferometry of fluids. Computed tomography and neural net calibration tomography are shown to have comparable performance for a 10 degree viewing cone and 29 interferograms within that cone. The system of tomography discussed is proposed as a relevant test of neural networks and other parallel processors intended for using flow visualization data.

  9. Objective Calibration of Sunspot Numbers

    NASA Astrophysics Data System (ADS)

    Svalgaard, L.

    2010-12-01

    Waldmeier [1971] found a very tight relationship between the F10.7 solar radio flux and the sunspot number and suggested using the flux for an objective calibration of the sunspot number. He suggested that if this relationship changed later on, the sunspot number should be re-calibrated, assuming that the calibration must have drifted with time. I repeat his analysis using data up to the present and it is, indeed, clear that the relationship has changed significantly. This could be due to a drift of the calibration or to a secular change in the visibility of sunspots, or both.

  10. Laboratory calibration of field reflectance panels

    NASA Technical Reports Server (NTRS)

    Biggar, S. F.; Labed, J.; Santer, R. P.; Slater, P. N.; Jackson, R. D.

    1988-01-01

    A method used for calibrating field reflectance panels in the visible and shortwave infrared wavelength range is described. The directional reflectance factor of painted barium sulfate (BaSO4) panels is determined. The reference for this method is the hemispherical reflectance of pressed polytetrafluoroethylene (halon) powder prepared according to National Bureau of Standards (NBS) directions. The panels and a radiometer are mounted on rotation stages to measure the reflectance factor at different incidence and view angles. The sensor can be any laboratory or field filter radiometer small enough to mount on the apparatus. The method is used to measure the reflectance factors of halon and BaSO4 panels between 0.45 and 0.85 micrometers. These reflectance factors are compared to those measured by a field apparatus. The results agree to within 0.013 in reflectance at incidence angles between 15 and 75 degrees.

  11. Update of the Photometric Calibration of the LASCO-C2 Coronagraph Using Stars

    NASA Astrophysics Data System (ADS)

    Colaninno, R. C.; Howard, R. A.

    2015-03-01

    We present an update to the photometric calibration of the LASCO-C2 coronagraph onboard the SOHO spacecraft. We obtained the new calibration using data from the beginning of the mission in 1996 until 2013. We re-examined the LASCO-C2 photometric calibration by comparing the past three calibrations and the present calibration with the goal of validating an in-flight calibration. We find a photometric calibration factor (PCF) that is very similar to the factor recently published in Gardès, Lamy, and Llebaria ( Solar Phys. 283, 667, 2013), which calculated a calibration between 1996 and 2009. The average of our PCF between 1999 and 2009 is the same, within our margin of error, as the average given by Gardès, Lamy, and Llebaria ( Solar Phys. 283, 667, 2013) during the same time period. However, we find a different evolution of the calibration over the lifetime of the LASCO-C2 instrument compared with past results. We find that the sensitivity of the instrument is decreasing by a constant 0.20 [±0.03] % per year. We also find no significant difference in the signal degradation before and after the SOHO interruption. We discuss the effects of this new PCF on the calibrated data set and the potential impact on scientific results derived from the previous calibration.

  12. MODIS Solar Calibration Simulation Assisted Refinement

    NASA Technical Reports Server (NTRS)

    Waluschka, Eugene; Xiaoxiong, Xiong; Guenther, Bruce; Barnes, William; Moyer, David; Salomonson, Vincent V.

    2004-01-01

    A detailed optical radiometric model has been created of the MODIS instruments solar calibration process. This model takes into account the orientation and distance of the spacecraft with respect to the sun, the correlated motions of the scan mirror and the sun, all of the optical elements, the detector locations on the visible and near IR focal planes, the solar diffuser and the attenuation screen with all of its hundreds of pinholes. An efficient computational scheme, takes into account all of these factors and has produced results which reproduce the observed time dependent intensity variations on the two focal planes with considerable fidelity. This agreement between predictions and observations, has given insight to the causes of some small time dependent variations and how to incorporate them into the overall calibration scheme. The radiometric model is described and modeled and actual measurements are presented and compared.

  13. REVIEW OF SCIENTIFIC INSTRUMENTS 84, 034706 (2013) In situ broadband cryogenic calibration for two-port superconducting

    E-print Network

    Anlage, Steven

    2013-01-01

    quality factor of the cavity.8,9 Examination of the predictions of RMT in very low loss systems; accepted 9 March 2013; published online 26 March 2013) We introduce an improved microwave calibration of this in situ broadband cryogenic calibration system utilizing cryogenic switches. All calibration measurements

  14. Proof-of-concept demonstration of a total internal reflection based module for fluorescence and absorbance detection using a 3D-printed syringe pump

    NASA Astrophysics Data System (ADS)

    Verschooten, Tom; Ottevaere, Heidi; Vervaeke, Michael; Van Erps, Jürgen; Thienpont, Hugo

    2014-05-01

    In this paper we demonstrate the proof-of-concept of an optofluidic module capable of simultaneous laser-induced fluorescence (LIF) and absorbance (ABS) detection based on total internal reflection (TIR) optics. We discuss the design of the optofluidic detection module, its fabrication, and the setup used for the proof-of-concept. The injection of sample under test is done using two 3D printed syringe pumps, managing accurate injection and repeatable sample propagation through the detector module. We discuss the process of development behind these pumps and review their technical specifications. With this demonstrator setup we find that the limits of detection for the ABS and LIF detection of coumarin 480 are 500 nM and 100 nM respectively.

  15. Immunogenicity and safety of measles-mumps-rubella vaccine delivered by disposable-syringe jet injector in healthy Brazilian infants: a randomized non-inferiority study.

    PubMed

    de Menezes Martins, Reinaldo; Curran, Birute; Maia, Maria de Lourdes Sousa; Ribeiro, Maria das Graças Tavares; Camacho, Luiz Antonio Bastos; da Silva Freire, Marcos; Yamamura, Anna Maya Yoshida; Siqueira, Marilda Mendonça; Lemos, Maria Cristina F; de Albuquerque, Elizabeth Maciel; von Doellinger, Vanessa dos Reis; Homma, Akira; Saganic, Laura; Jarrahian, Courtney; Royals, Michael; Zehrung, Darin

    2015-03-01

    This study aimed to determine if immunogenicity to measles-mumps-rubella vaccine delivered to infants via a disposable-syringe jet injector (DSJI) was non-inferior to that administered by needle and syringe (NS). Vaccination safety was evaluated, as were the use, performance, and acceptability of each delivery method. The DSJI was the PharmaJet 2009 generation-1 device (G1) and the vaccine was measles-mumps-rubella vaccine from Bio-Manguinhos. Five hundred eighty-two healthy Brazilian infants were randomized to receive vaccine via G1 or NS. Seroconversion rates against measles and mumps viruses in the G1 treatment group did not meet non-inferiority criteria when compared with the NS group; however, responses in the G1 group to rubella virus were non-inferior to those of NS vaccinees. Most adverse events were mild or moderate. Crying after injection was more frequent in the NS group, and local skin reactions were more common in the G1 group. Five serious adverse events were judged causally unrelated to treatment and all resolved. Parents/guardians expressed a strong preference for G1 over NS for their children. Vaccinators found the G1 easy to use but noted incomplete vaccine delivery in some cases. Although the G1 has been superseded by an updated device, our results are important for the continued improvement and evaluation of DSJIs, which have the potential to overcome many of the challenges and risks associated with needle-based injections worldwide. Recommendations for future DSJI clinical studies include rigorous training of vaccinators, quantitative measurement of wetness on the skin following injection, and regular monitoring of device and vaccinator performance. PMID:25476584

  16. Automatic flowmeter calibration system

    NASA Technical Reports Server (NTRS)

    Lisle, R. V.; Wilson, T. L. (inventor)

    1981-01-01

    A system for automatically calibrating the accuracy of a flowmeter is described. The system includes a calculator capable of performing mathematical functions responsive to receiving data signals and function command signals. A prover cylinder is provided for measuring the temperature, pressure, and time required for accumulating a predetermined volume of fluid. Along with these signals, signals representing the temperature and pressure of the fluid going into the meter are fed to a plurality of data registers. Under control of a progress controller, the data registers are read out and the information is fed through a data select circuit to the calculator. Command signals are also produced by a function select circuit and are fed to the calculator set indicating the desired function to be performed. The reading is then compared with the reading produced by the flowmeter.

  17. Inspection system calibration methods

    DOEpatents

    Deason, Vance A.; Telschow, Kenneth L.

    2004-12-28

    An inspection system calibration method includes producing two sideband signals of a first wavefront; interfering the two sideband signals in a photorefractive material, producing an output signal therefrom having a frequency and a magnitude; and producing a phase modulated operational signal having a frequency different from the output signal frequency, a magnitude, and a phase modulation amplitude. The method includes determining a ratio of the operational signal magnitude to the output signal magnitude, determining a ratio of a 1st order Bessel function of the operational signal phase modulation amplitude to a 0th order Bessel function of the operational signal phase modulation amplitude, and comparing the magnitude ratio to the Bessel function ratio.

  18. Atmospheric optical calibration system

    DOEpatents

    Hulstrom, Roland L. (Bloomfield, CO); Cannon, Theodore W. (Golden, CO)

    1988-01-01

    An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions.

  19. RX130 Robot Calibration

    NASA Astrophysics Data System (ADS)

    Fugal, Mario

    2012-10-01

    In order to create precision magnets for an experiment at Oak Ridge National Laboratory, a new reverse engineering method has been proposed that uses the magnetic scalar potential to solve for the currents necessary to produce the desired field. To make the magnet it is proposed to use a copper coated G10 form, upon which a drill, mounted on a robotic arm, will carve wires. The accuracy required in the manufacturing of the wires exceeds nominal robot capabilities. However, due to the rigidity as well as the precision servo motor and harmonic gear drivers, there are robots capable of meeting this requirement with proper calibration. Improving the accuracy of an RX130 to be within 35 microns (the accuracy necessary of the wires) is the goal of this project. Using feedback from a displacement sensor, or camera and inverse kinematics it is possible to achieve this accuracy.

  20. Distributed Calibration of Smart Cameras

    Microsoft Academic Search

    John Jannotti; Jie Mao

    Localization in sensornets determines the location of sensor nodes, and allows applications to make geograph- ically sensitive queries. Smart camera networks must not only be localized, but calibrated. Calibration goes beyond localization to include orientation and position information that is sufficiently fine-grained to allow fu- sion between overlapping camera views. This paper introduces Lighthouse, a distributed calibra- tion system that

  1. Calibration of a Horizontal Sundial

    ERIC Educational Resources Information Center

    Rovsek, Barbara

    2010-01-01

    This paper describes how a horizontal sundial can be calibrated in a classroom without using the nontrivial equations of projective geometry. If one understands how a simple equatorial sundial works, one will also understand the procedure of calibrating a horizontal (or "garden," as it is also called) sundial.

  2. Camera Calibration with Known Rotation

    Microsoft Academic Search

    Jan-michael Frahm; Reinhard Koch

    2003-01-01

    We address the problem of using external rotation informa- tion with uncalibrated video sequences. The main problem addressed is, what is the benefit of the orientation infor- mation for camera calibration? It is shown that in case of a rotating camera the camera calibration problem is lin- ear even in the case that all intrinsic parameters vary. For arbitrarily moving

  3. Antenna Position Calibration Melvyn Wright

    E-print Network

    Antenna Position Calibration Melvyn Wright Radio Astronomy laboratory, University of California, Berkeley, CA, 94720 ABSTRACT This memo summarizes the antenna position calibration used at Hat Creek of HA and DEC provide data from which the antenna positions are determined. If the antenna positions

  4. Method for Accurately Calibrating a Spectrometer Using Broadband Light

    NASA Technical Reports Server (NTRS)

    Simmons, Stephen; Youngquist, Robert

    2011-01-01

    A novel method has been developed for performing very fine calibration of a spectrometer. This process is particularly useful for modern miniature charge-coupled device (CCD) spectrometers where a typical factory wavelength calibration has been performed and a finer, more accurate calibration is desired. Typically, the factory calibration is done with a spectral line source that generates light at known wavelengths, allowing specific pixels in the CCD array to be assigned wavelength values. This method is good to about 1 nm across the spectrometer s wavelength range. This new method appears to be accurate to about 0.1 nm, a factor of ten improvement. White light is passed through an unbalanced Michelson interferometer, producing an optical signal with significant spectral variation. A simple theory can be developed to describe this spectral pattern, so by comparing the actual spectrometer output against this predicted pattern, errors in the wavelength assignment made by the spectrometer can be determined.

  5. Calibration and high fidelity measurement of a quantum photonic chip

    NASA Astrophysics Data System (ADS)

    Li, H. W.; Wabnig, J.; Bitauld, D.; Shadbolt, P.; Politi, A.; Laing, A.; O'Brien, J. L.; Niskanen, A. O.

    2013-06-01

    Integrated quantum photonic circuits are becoming increasingly complex. Accurate calibration of device parameters and detailed characterization of the prepared quantum states are critically important for future progress. Here we report on an effective experimental calibration method based on Bayesian updating and Markov chain Monte Carlo integration. We use this calibration technique to characterize a two qubit chip and extract the reflectivities of its directional couplers. An average quantum state tomography fidelity of 93.79 ± 1.05% against the four Bell states is achieved. Furthermore, comparing the measured density matrices against a model using the non-ideal device parameters derived from the calibration we achieve an average fidelity of 97.57 ± 0.96%. This pinpoints non-ideality of chip parameters as a major factor in the decrease of Bell state fidelity. We also perform quantum state tomography for Bell states while continuously varying photon distinguishability and find excellent agreement with theory.

  6. UV/VUV radiometric calibrations at SURF II

    NASA Astrophysics Data System (ADS)

    Furst, Mitchell L.; Canfield, L. R.

    1993-01-01

    Since 1981 more than 150 instrument calibrations have been performed on the radiometric instrumentation calibration beamline at the Synchrotron Ultraviolet Radiation Facility (SURF II) at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland. This 300 MeV electron storage ring operates routinely at electron currents greater than 250 mA. The spectrometer calibration beamline provides a continuum of radiation from 4 nm through the visual spectral region in the form of an intense beam with total angular divergence of 1.2 mrad. The probable uncertainty for the flux ranges from about 5 percent at 4 nm to less than 2 percent above 20 nm. The new system will radiometrically trace to SURF II, and thus is expected to reduce the calibration uncertainty for diodes in this region by a factor of five to the 1-2 percent level.

  7. Digital camera self-calibration

    NASA Astrophysics Data System (ADS)

    Fraser, C.

    1997-08-01

    Over the 25 years since the introduction of analytical camera self-calibration there has been a revolution in close-range photogrammetric image acquisition systems. High-resolution, large-area "digital" CCD sensors have all but replaced film cameras. Throughout the period of this transition, self-calibration models have remained essentially unchanged. This paper reviews the application of analytical self-calibration to digital cameras. Computer vision perspectives are touched upon, the quality of self-calibration is discussed, and an overview is given of each of the four main sources of departures from collinearity in CCD cameras. Practical issues are also addressed and experimental results are used to highlight important characteristics of digital camera self-calibration.

  8. Digital camera self-calibration

    NASA Astrophysics Data System (ADS)

    Fraser, Clive S.

    Over the 25 years since the introduction of analytical camera self-calibration there has been a revolution in close-range photogrammetric image acquisition systems. High-resolution, large-area 'digital' CCD sensors have all but replaced film cameras. Throughout the period of this transition, self-calibration models have remained essentially unchanged. This paper reviews the application of analytical self-calibration to digital cameras. Computer vision perspectives are touched upon, the quality of self-calibration is discussed, and an overview is given of each of the four main sources of departures from collinearity in CCD cameras. Practical issues are also addressed and experimental results are used to highlight important characteristics of digital camera self-calibration.

  9. Mercury Continuous Emmission Monitor Calibration

    SciTech Connect

    John Schabron; Eric Kalberer; Ryan Boysen; William Schuster; Joseph Rovani

    2009-03-12

    Mercury continuous emissions monitoring systems (CEMs) are being implemented in over 800 coal-fired power plant stacks throughput the U.S. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor calibrators/generators. These devices are used to calibrate mercury CEMs at power plant sites. The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005 and vacated by a Federal appeals court in early 2008 required that calibration be performed with NIST-traceable standards. Despite the vacature, mercury emissions regulations in the future will require NIST traceable calibration standards, and EPA does not want to interrupt the effort towards developing NIST traceability protocols. The traceability procedures will be defined by EPA. An initial draft traceability protocol was issued by EPA in May 2007 for comment. In August 2007, EPA issued a conceptual interim traceability protocol for elemental mercury calibrators. The protocol is based on the actual analysis of the output of each calibration unit at several concentration levels ranging initially from about 2-40 {micro}g/m{sup 3} elemental mercury, and in the future down to 0.2 {micro}g/m{sup 3}, and this analysis will be directly traceable to analyses by NIST. The EPA traceability protocol document is divided into two separate sections. The first deals with the qualification of calibrator models by the vendors for use in mercury CEM calibration. The second describes the procedure that the vendors must use to certify the calibrators that meet the qualification specifications. The NIST traceable certification is performance based, traceable to analysis using isotope dilution inductively coupled plasma/mass spectrometry (ID/ICP/MS) performed by NIST in Gaithersburg, MD. The outputs of mercury calibrators are compared to one another using a nesting procedure which allows direct comparison of one calibrator with another at specific concentrations and eliminates analyzer variability effects. The qualification portion of the EPA interim traceability protocol requires the vendors to define calibrator performance as affected by variables such as pressure, temperature, line voltage, and shipping. In 2007 WRI developed and conducted a series of simplified qualification experiments to determine actual calibrator performance related to the variables defined in the qualification portion of the interim protocol.

  10. A Novel Protocol for Model Calibration in Biological Wastewater Treatment

    NASA Astrophysics Data System (ADS)

    Zhu, Ao; Guo, Jianhua; Ni, Bing-Jie; Wang, Shuying; Yang, Qing; Peng, Yongzhen

    2015-02-01

    Activated sludge models (ASMs) have been widely used for process design, operation and optimization in wastewater treatment plants. However, it is still a challenge to achieve an efficient calibration for reliable application by using the conventional approaches. Hereby, we propose a novel calibration protocol, i.e. Numerical Optimal Approaching Procedure (NOAP), for the systematic calibration of ASMs. The NOAP consists of three key steps in an iterative scheme flow: i) global factors sensitivity analysis for factors fixing; ii) pseudo-global parameter correlation analysis for non-identifiable factors detection; and iii) formation of a parameter subset through an estimation by using genetic algorithm. The validity and applicability are confirmed using experimental data obtained from two independent wastewater treatment systems, including a sequencing batch reactor and a continuous stirred-tank reactor. The results indicate that the NOAP can effectively determine the optimal parameter subset and successfully perform model calibration and validation for these two different systems. The proposed NOAP is expected to use for automatic calibration of ASMs and be applied potentially to other ordinary differential equations models.

  11. Integrated calibration of magnetic gradient tensor system

    NASA Astrophysics Data System (ADS)

    Gang, Yin; Yingtang, Zhang; Hongbo, Fan; GuoQuan, Ren; Zhining, Li

    2015-01-01

    Measurement precision of a magnetic gradient tensor system is not only connected with the imperfect performance of magnetometers such as bias, scale factor, non-orthogonality and misalignment errors, but also connected with the external soft-iron and hard-iron magnetic distortion fields when the system is used as a strapdown device. So an integrated scalar calibration method is proposed in this paper. In the first step, a mathematical model for scalar calibration of a single three-axis magnetometer is established, and a least squares ellipsoid fitting algorithm is proposed to estimate the detailed error parameters. For the misalignment errors existing at different magnetometers caused by the installation process and misalignment errors aroused by ellipsoid fitting estimation, a calibration method for combined misalignment errors is proposed in the second step to switch outputs of different magnetometers into the ideal reference orthogonal coordinate system. In order to verify effectiveness of the proposed method, simulation and experiment with a cross-magnetic gradient tensor system are performed, and the results show that the proposed method estimates error parameters and improves the measurement accuracy of magnetic gradient tensor greatly.

  12. Calibration of the Oscillating Screen Viscometer

    NASA Technical Reports Server (NTRS)

    Berg, Robert F.; Moldover, Michael R.

    1993-01-01

    We have devised a calibration procedure for the oscillating screen viscometer which can provide the accuracy needed for the flight measurement of viscosity near the liquid-vapor critical point of xenon. The procedure, which makes use of the viscometer's wide bandwidth and hydrodynamic similarity, allows the viscometer to be self-calibrating. To demonstrate the validity of this procedure we measured the oscillator's transfer function under a wide variety of conditions. We obtained data using CO2 at temperatures spanning a temperature range of 35 K and densities varying by a factor of 165, thereby encountering viscosity variations as great as 50%. In contrast the flight experiment will be performed over a temperature range of 29 K and at only a single density, and the viscosity is expected to change by less than 40%. The measurements show that, after excluding data above 10 Hz (where frequency-dependent corrections are poorly modeled) and making a plausible adjustment to the viscosity value used at high density, the viscometer's behavior is fully consistent with the use of hydrodynamic similarity for calibration. Achieving this agreement required understanding a 1% anelastic effect present in the oscillator's torsion fiber.

  13. Comparison of On-Wafer Calibrations

    Microsoft Academic Search

    Dylan F. Williams; Roger B. Marks; Andrew Davidson

    1991-01-01

    A powerful new verification technique determines the measurement accuracy of scattering parameter calibrations. The technique determines the relative reference impedance, reference plane offset, and the worst-case measurement deviations of any calibration from a benchmark calibration. The technique is applied to several popular on-wafer scattering parameter calibrations, and the deviations between those calibrations and the thru-reflect line calibration are quantified.

  14. Mexican national pyronometer network calibration

    NASA Astrophysics Data System (ADS)

    VAldes, M.; Villarreal, L.; Estevez, H.; Riveros, D.

    2013-12-01

    In order to take advantage of the solar radiation as an alternate energy source it is necessary to evaluate the spatial and temporal availability. The Mexican National Meterological Service (SMN) has a network with 136 meteorological stations, each coupled with a pyronometer for measuring the global solar radiation. Some of these stations had not been calibrated in several years. The Mexican Department of Energy (SENER) in order to count on a reliable evaluation of the solar resource funded this project to calibrate the SMN pyrometer network and validate the data. The calibration of the 136 pyronometers by the intercomparison method recommended by the World Meterological Organization (WMO) requires lengthy observations and specific environmental conditions such as clear skies and a stable atmosphere, circumstances that determine the site and season of the calibration. The Solar Radiation Section of the Instituto de Geofísica of the Universidad Nacional Autónoma de México is a Regional Center of the WMO and is certified to carry out the calibration procedures and emit certificates. We are responsible for the recalibration of the pyronometer network of the SMN. A continuous emission solar simulator with exposed areas with 30cm diameters was acquired to reduce the calibration time and not depend on atmospheric conditions. We present the results of the calibration of 10 thermopile pyronometers and one photovoltaic cell by the intercomparison method with more than 10000 observations each and those obtained with the solar simulator.

  15. Rotary mode system initial instrument calibration

    SciTech Connect

    Johns, B.R.

    1994-10-01

    The attached report contains the vendor calibration procedures used for the initial instrument calibration of the rotary core sampling equipment. The procedures are from approved vendor information files.

  16. 21 CFR 862.1150 - Calibrator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1150 Calibrator. (a) Identification. A calibrator...

  17. 21 CFR 862.1150 - Calibrator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1150 Calibrator. (a) Identification. A calibrator...

  18. Calibration drift in a laboratory high purity germanium detector spectrometry system.

    PubMed

    Dewey, S C; Kearfott, K J

    2008-02-01

    For unknown radionuclide identification, it is important that a high purity germanium (HPGe) spectrometry system be calibrated correctly for energy. The energy calibration of an HPGe spectrometry system will drift over time due to a variety of factors including the ambient temperature, the line voltage applied to the system, variation in the electronics, and other possible influences. In order to better understand the nature of this energy calibration drift, calibration spectra were collected over a period of several months from a laboratory HPGe spectrometry system. System parameters, including detector voltage, amplifier gain, and preamplifier gain, were not deliberately modified during the course of the experiment. The system was calibrated routinely over the 90 days, and the results of the calibrations were compared in order to assess the drift in the energy calibration of the detector over time. The analysis of a 36% high purity germanium system demonstrated the energy calibration drifted an average of 0.014 keV d(-1) to 0.041 keV d(-1) depending upon energy. At 1,332 keV, one day after calibration, it was shown that up to half of the total error in energy calibration was as a result of calibration drift. PMID:18192795

  19. Diode calibration manual

    SciTech Connect

    Brunk, J.L.

    1989-09-01

    This procedure is not for the faint of heart. It is a time consuming, complex series of journeys through advanced GAMANAL and the vagueness of analyzer electronics. A knowledge of TRIX AC, DLTV, and IMP on the Octopus system and DSCOPE, PE2, and Symphony on a PC class machine is required. Be aware that the example in this document is a condensation of information that takes up four feet of shelf space. In the attempt to convert the nomenclature of the 7600 version of GAMANAL to that of the CRAY version, there will be confusion with some of the terms used. The 7600 versions relied on punched cards to a great extent where the CRAY version doesn't use them at all. In order not to introduce a new set of nomenclature, I have changed the reference from card to card image. I hope that this will cause the least impact on the vernacular and cause the least amount of confusion possible. This document is a rewritten update of an unpublished document by Bob Wikkerink in 1980. His document was the only written record of the procedures needed to calibrate the Environmental Sciences Low Level Counting Facility. This document updates and expands this information.

  20. The calibration methods for Multi-Filter Rotating Shadowband Radiometer: a review

    NASA Astrophysics Data System (ADS)

    Chen, Maosi; Davis, John; Tang, Hongzhao; Ownby, Carolyn; Gao, Wei

    2013-09-01

    The continuous, over two-decade data record from the Multi-Filter Rotating Shadowband Radiometer (MFRSR) is ideal for climate research which requires timely and accurate information of important atmospheric components such as gases, aerosols, and clouds. Except for parameters derived from MFRSR measurement ratios, which are not impacted by calibration error, most applications require accurate calibration factor(s), angular correction, and spectral response function(s) from calibration. Although a laboratory lamp (or reference) calibration can provide all the information needed to convert the instrument readings to actual radiation, in situ calibration methods are implemented routinely (daily) to fill the gaps between lamp calibrations. In this paper, the basic structure and the data collection and pretreatment of the MFRSR are described. The laboratory lamp calibration and its limitations are summarized. The cloud screening algorithms for MFRSR data are presented. The in situ calibration methods, the standard Langley method and its variants, the ratio-Langley method, the general method, Alexandrov's comprehensive method, and Chen's multi-channel method, are outlined. The reason that all these methods do not fit for all situations is that they assume some properties, such as aerosol optical depth (AOD), total optical depth (TOD), precipitable water vapor (PWV), effective size of aerosol particles, or angstrom coefficient, are invariant over time. These properties are not universal and some of them rarely happen. In practice, daily calibration factors derived from these methods should be smoothed to restrain error.

  1. Weed Busters: Sprayer Calibration Guide 

    E-print Network

    McGinty, Allan; Hanselka, C. Wayne; Lyons, Robert K.; Hart, Charles R.; Cadenhead, J. F.

    2005-03-07

    to rangeland. ?Broadcast sprays can drift, especially when boom- less nozzles are used. ?Read and follow the herbicide label directions. L-5465 1/05 Sprayer Calibration Guide Safe and effective four-step method to calibrate herbicide sprays Weed Treatment... is important. If you apply too much herbicide, costs can become excessive; you may be in violation of the label; and you might cause environmental dam- age. If you apply too little herbicide, the weeds may not be controlled adequately. Many sprayer calibration...

  2. Radiometric Compensation and Calibration for Radarsat ScanSAR

    NASA Technical Reports Server (NTRS)

    Jin, Michael Y.

    1993-01-01

    Due to lack of a standard for modeling the radar echo signal in terms of signal unit and coordinates as well as lack of a standard in designing the gain factors in each stage of a processor, absolute radiometric calibration of a SAR system is usually performed by treating the sensor and processor as one inseparable unit. This often makes the calibration procedure complicated and requiring the involvement of both radar system engineers and processor engineers in the whole process. This paper introduces a standard for modeling the radar echo signal and a standard in designing the gain factor of a ScanSAR processor. In this paper, the radar equation is derived based on the amount of energy instead of the power received from a backscatterer. These efforts lead to simple and easy-to-understand equations for radiometric compensation and calibration.

  3. A first order wavefront estimation algorithm for P1640 calibrator

    NASA Astrophysics Data System (ADS)

    Zhai, C.; Vasisht, G.; Shao, M.; Lockhart, T.; Cady, E.; Oppenheimer, B.; Burruss, R.; Roberts, J.; Beichman, C.; Brenner, D.; Crepp, J.; Dekany, R.; Hinkley, S.; Hillenbrand, L.; Ligon, E. R.; Parry, I.; Pueyo, L.; Rice, E.; Roberts, L. C.; Sivaramakrishnan, A.; Soummer, R.; Vescelus, F.; Wallace, K.; Zimmerman, N.

    2012-07-01

    P1640 calibrator is a wavefront sensor working with the P1640 coronagraph and the Palomar 3000 actuator adaptive optics system (P3K) at the Palomar 200 inch Hale telescope. It measures the wavefront by interfering post-coronagraph light with a reference beam formed by low-pass filtering the blocked light from the coronagraph focal plane mask. The P1640 instrument has a similar architecture to the Gemini Planet Imager (GPI) and its performance is currently limited by the quasi-static speckles due to non-common path wavefront errors, which comes from the non-common path for the light to arrive at the AO wavefront sensor and the coronagraph mask. By measuring the wavefront after the coronagraph mask, the non-common path wavefront error can be estimated and corrected by feeding back the error signal to the deformable mirror (DM) of the P3K AO system. Here, we present a first order wavefront estimation algorithm and an instrument calibration scheme used in experiments done recently at Palomar observatory. We calibrate the P1640 calibrator by measuring its responses to poking DM actuators with a sparse checkerboard pattern at different amplitudes. The calibration yields a complex normalization factor for wavefront estimation and establishes the registration of the DM actuators at the pupil camera of the P1640 calibrator, necessary for wavefront correction. Improvement of imaging quality after feeding back the wavefront correction to the AO system demonstrated the efficacy of the algorithm.

  4. A First Order Wavefront Estimation Algorithm for P1640 Calibrator

    NASA Technical Reports Server (NTRS)

    Zhaia, C.; Vasisht, G.; Shao, M.; Lockhart, T.; Cady, E.; Oppenheimer, B.; Burruss, R.; Roberts, J.; Beichman, C.; Brenner, D.; Crepp, J.; Dekany, R.; Hinkley, S.; Hillenbrand, L.; Parry, I.; Pueyo, L.; Rice, E.; Roberts, L. C. Jr.; Sivaramakrishnan, A.; Soummer, R.; Vescelus, F.; Wallace, K.; Zimmerman, N.

    2012-01-01

    P1640 calibrator is a wavefront sensor working with the P1640 coronagraph and the Palomar 3000 actuator adaptive optics system (P3K) at the Palomar 200 inch Hale telescope. It measures the wavefront by interfering post-coronagraph light with a reference beam formed by low-pass filtering the blocked light from the coronagraph focal plane mask. The P1640 instrument has a similar architecture to the Gemini Planet Imager (GPI) and its performance is currently limited by the quasi-static speckles due to non-common path wavefront errors, which comes from the non-common path for the light to arrive at the AO wavefront sensor and the coronagraph mask. By measuring the wavefront after the coronagraph mask, the non-common path wavefront error can be estimated and corrected by feeding back the error signal to the deformable mirror (DM) of the P3K AO system. Here, we present a first order wavefront estimation algorithm and an instrument calibration scheme used in experiments done recently at Palomar observatory. We calibrate the P1640 calibrator by measuring its responses to poking DM actuators with a sparse checkerboard pattern at different amplitudes. The calibration yields a complex normalization factor for wavefront estimation and establishes the registration of the DM actuators at the pupil camera of the P1640 calibrator, necessary for wavefront correction. Improvement of imaging quality after feeding back the wavefront correction to the AO system demonstrated the efficacy of the algorithm.

  5. Review of SU(2)-Calibrations

    E-print Network

    Andre Miemiec

    2005-10-27

    The purpose of this article is to provide a review of SU(2)-calibrations. The focus is on developing all techniques in full detail by studying selected examples. The supergravity point of view and the string theoretic one are explained.

  6. Constructing and Calibrating a Hydrometer

    NSDL National Science Digital Library

    Meghan Hauptli

    2012-04-18

    Students construct and calibrate a simple hydrometer using different salt solutions. They then graph their data and determine the density and salinity of an unknown solution using their hydrometer and graphical analysis.

  7. Fast-camera calibration of stereo vision system using BP neural networks

    Microsoft Academic Search

    Huimin Cai; Kejie Li; Meilian Liu; Ping Song

    2010-01-01

    In position measurements by far-range photogrammetry, the scale between object and image has to be calibrated. It means to get the parameters of the perspective projection matrix. Because the image sensor of fast-camera is CMOS, there are many uncertain distortion factors. It is hard to describe the scale between object and image for the traditional calibration based on the mathematical

  8. Calibration-Free Augmented Reality

    Microsoft Academic Search

    Kiriakos N. Kutulakos; James R. Vallino

    1998-01-01

    Camera calibration and the acquisition of Euclidean 3D measurements have so far been con- sidered necessary requirements for overlaying three-dime nsional graphical objects with live video. In this article we describe a new approach to video-based augmented reality that avoids both re- quirements: it does not use any metric information about the calibration parameters of the camera or the 3D

  9. Camera calibration using identical objects

    Microsoft Academic Search

    Ruiyan Wang; Guang Jiang; Long Quan; Chengke Wu

    This paper describes a method for camera calibration using identical products. In this paper, we postulate an imaginative\\u000a rigid motion between any two identical products, and the imaginative rigid motion could offer a pair of circular points. As\\u000a is known, three pairs of projections of the circular points are needed to result in the closed-form solution for calibration.\\u000a In our

  10. Recent Developments in Multivariate Calibration

    Microsoft Academic Search

    Jon Gabrielsson; Johan Trygg

    2006-01-01

    This review covers the area of multivariate calibration; from pre-processing of data prior to modeling and applications of regression methods for calibration and prediction. The importance of pre-treatment of data is highlighted with many of the recently developed methods together with traditional methods. Several articles provide comparisons between different pre-processing methods. Methods for data from coupled chromatographic methods, which have

  11. PALSAR Radiometric and Geometric Calibration

    Microsoft Academic Search

    Masanobu Shimada; Osamu Isoguchi; Takeo Tadono; Kazuo Isono

    2009-01-01

    This paper summarizes the results obtained from geometric and radiometric calibrations of the Phased-Array L-Band Synthetic Aperture Radar (PALSAR) on the Advanced Land Observing Satellite, which has been in space for three years. All of the imaging modes of the PALSAR, i.e., single, dual, and full polarimetric strip modes and scanning synthetic aperture radar (SCANSAR), were calibrated and validated using

  12. Combination Calibration of Digital Cameras

    Microsoft Academic Search

    Feng Qiqiang; Li Zongchun; Li Guangyun; Chen Xin

    2009-01-01

    The paper presents a combination calibration method of digital cameras based on the ten-parameter model and the finite element model. The predictable distortion errors can be compensated with the ten-parameter model while the unpredictable ones compensated with the finite element model. A calibration experiment has been carried out on the metric camera Inca3 and non-metric cameras Canon 5D Mark II

  13. ERS-1 calibration and validation

    Microsoft Academic Search

    E. Attema; R. Francis

    1991-01-01

    The facilities and procedures to be used in calibrating and validating the remote-sensing instruments of the ESA ERS-1 satellite are described and illustrated with drawings, maps, and photographs. Sections are devoted to the engineering calibration of the Active Microwave Instrument (using ground transponders in the Netherlands and Spain for the image\\/wave-mode SAR and the wind scatterometer, respectively), the radar altimeter

  14. CALIBRATION OF PU INTENSITY PROBES

    Microsoft Academic Search

    Virginie Jaud; Finn Jacobsen

    A pressure-velocity sound intensity probe (or a 'p-u intensity probe') is a device that combines a pressure microphone with an acoustic particle velocity transducer. Such devices are mush more difficult to calibrate than sound intensity probes that combines closely spaced pressure microphones ('p-p intensity probes'). Various methods of calibrating p-u sound in- tensity probes are examined: a far field method

  15. Calibration wafer for temperature measurements in RTP tools

    NASA Astrophysics Data System (ADS)

    Kreider, K. G.; DeWitt, D. P.; Tsai, B. K.; Lovas, F. J.; Allen, D. W.

    1998-11-01

    Rapid thermal processing (RTP) is a key technology that is used to produce integrated circuits at lower cost and reduced thermal budgets. One of the limiting factors in expanding the use of RTP is the accuracy of temperature measurements of the wafer during processing. We are developing a wafer for calibrating radiometric temperature measurements in RTP tools. The calibration wafer incorporates thin-film thermocouples with platinum/palladium (Pt/Pd) wire thermocouples welded to thin-film pads at the periphery of the 200 mm wafers. We have reduced the uncertainty of the temperature measurements up to 1200 K with this system. This has been accomplished by reducing the uncertainty due to the thermocouple itself and due to reduction of heat transfer near the junction.We report results of NIST calibrations of radiometers using Pt/Pd wire thermocouples welded to the thin films on the wafer and of calibrated type K thermocouples. The thin-film thermocouples were sputter deposited from high purity Pt, Pd and Rh. These thin-film thermocouples were calibrated by comparison with Pt/Pd wire thermocouples in a specially designed test cell at temperatures up to 1150 K. Radiometric temperature measurements were made on the calibration wafer in the NIST RTP sensor test bed, using a commercial radiometer, and compared to those obtained from the thermocouple measurements. A model is presented to account for errors in the radiometric measurements due to stray radiation from the heating lamps, reflection of wafer emission from the chamber walls, and wafer emissivity. The calibrated type K thermocouples indicated temperature measurements within 4 K of both the Rh/Pt and Pt/Pd thermocouples on the 200 mm calibration wafer between 1000 K and 1150 K. The Pt/Pd thin films proved less durable than the Rh/Pt thin films and the limitations of these systems are discussed.

  16. Bundling occupational safety with harm reduction information as a feasible method for improving police receptiveness to syringe access programs: evidence from three U.S. cities

    PubMed Central

    Davis, Corey S; Beletsky, Leo

    2009-01-01

    Introduction In light of overwhelming evidence that access to sterile injection equipment reduces incidence of injection-attributable bloodborne disease without encouraging drug use, many localities have authorized sterile syringe access programs (SAPs), including syringe exchange and pharmacy-based initiatives. Even where such interventions are clearly legal, many law enforcement officers are unaware of the public health benefits and legal status of these programs and may continue to treat the possession of injection equipment as illegal and program participation as a marker of illegal behavior. Law enforcement practice can impede SAP utilization and may increase the risk of needlestick injury (NSI) among law enforcement personnel. Many SAPs conduct little or no outreach to law enforcement, in part because they perceive law enforcement actors as unreceptive to health-promotion programs targeting drug users. Case description We report on a brief training intervention for law enforcement personnel designed to increase officer knowledge of and positive attitudes towards SAPs by bundling content that addresses officer concerns about infectious disease and occupational safety with information about the legality and public health benefits of these programs. Pilot trainings using this bundled curriculum were conducted with approximately 600 officers in three US cities. Discussion and evaluation Law enforcement officers were generally receptive to receiving information about SAPs through the bundled curriculum. The trainings led to better communication and collaboration between SAP and law enforcement personnel, providing a valuable platform for better harmonization of law enforcement and public health activities targeting injection drug users. Conclusion The experience in these three cities suggests that a harm reduction training curriculum that bundles strategies for increasing officer occupational safety with information about the legality and public health benefits of SAPs can be well received by law enforcement personnel and can lead to better communication and collaboration between law enforcement and harm reduction actors. Further study is indicated to assess whether such a bundled curriculum is effective in changing officer attitudes and beliefs and reducing health risks to officers and injection drug users, as well as broader benefits to the community at large. PMID:19602236

  17. Stability of Bortezomib 2.5 mg/mL in Vials and Syringes Stored at 4°C and Room Temperature (23°C)

    PubMed Central

    Walker, Scott E; Charbonneau, Lauren F; Law, Shirley

    2014-01-01

    Background: Solutions of bortezomib 1.0 mg/mL for IV administration are reportedly stable for up to 42 days. Recent publications have reported that the safety profile of bortezomib is better with subcutaneous administration than with IV administration. Objective: To evaluate the stability of higher-concentration bortezomib solutions for subcutaneous administration (i.e., 2.5 mg/mL in 0.9% sodium chloride [normal saline or NS]). Methods: On study day 0, twelve 3.5-mg vials of powdered bortezomib were each reconstituted with 1.4 mL of NS to prepare solutions with concentration 2.5 mg/mL. Half of the solutions were subsequently stored in the original vials and half were transferred to syringes. Three of each type of container were stored in the refrigerator (4°C) and the other 3 of each type were stored at room temperature (23°C). Concentration analysis and physical inspection were completed on study days 0, 1, 2, 8, 12, 14, 19, and 21. The concentration of bortezomib was determined by a validated liquid chromatographic method with ultraviolet detection. The expiry date was determined according to the time to achieve 90% of the initial concentration, based on the fastest degradation rate calculated from the 95% confidence interval of the observed degradation rate. Results: The analytical method separated degradation products from bortezomib such that the concentration was measured specifically and accurately (with absolute deviations from known concentration averaging 2.99%), with intraday and interday reproducibility averaging 1.51% and 2.51%, respectively. During the study period, all solutions were observed to retain at least 95.26% of the initial concentration in both types of containers at both temperatures. Conclusions: Bortezomib (3.5 mg in manufacturer’s vial) reconstituted with 1.4 mL NS is physically and chemically stable for up to 21 days at 4°C or 23°C when stored in either the manufacturer’s original glass vial or a syringe. Subcutaneous injection of bortezomib represents a change in practice, and there is a potential safety concern if a solution of the increased concentration used for subcutaneous administration (2.5 mg/mL) is inadvertently used to prepare a dose intended for IV administration. Therefore, it is recommended that sites switching to subcutaneous administration of bortezomib eliminate 1.0 mg/mL IV solutions altogether or institute substantial barriers to prevent IV administration of the higher concentration of bortezomib. PMID:24799719

  18. Design of Experiments for Calibration of Planar Anthropomorphic Manipulators

    E-print Network

    Paris-Sud XI, Université de

    of optimal calibration experiments for a planar anthropomorphic manipulator with n degrees of freedom intuitively promising and perfectly corresponds to some basic ideas of the classical theory [17] that intends using the factors that are distinct as much as possible. However, the classical results are mostly

  19. Evaluation of Procedures for Linking Multidimensional Item Calibrations.

    ERIC Educational Resources Information Center

    Oshima, T. C.; Davey, T. C.

    This paper evaluated multidimensional linking procedures with which multidimensional test data from two separate calibrations were put on a common scale. Data were simulated with known ability distributions varying on two factors which made linking necessary: mean vector differences and variance-covariance (v-c) matrix differences. After the…

  20. SCUBA-2: on-sky calibration using submillimetre standard sources

    NASA Astrophysics Data System (ADS)

    Dempsey, J. T.; Friberg, P.; Jenness, T.; Tilanus, R. P. J.; Thomas, H. S.; Holland, W. S.; Bintley, D.; Berry, D. S.; Chapin, E. L.; Chrysostomou, A.; Davis, G. R.; Gibb, A. G.; Parsons, H.; Robson, E. I.

    2013-04-01

    SCUBA-2 is a 10 000-bolometer submillimetre camera on the James Clerk Maxwell Telescope. The instrument commissioning was completed in 2011 September, and full science operations began in 2011 October. To harness the full potential of this powerful new astronomical tool, the instrument calibration must be accurate and well understood. To this end, the algorithms for calculating the line-of-sight opacity have been improved, and the derived atmospheric extinction relationships at both wavebands of the SCUBA-2 instrument are presented. The results from over 500 primary and secondary calibrator observations have allowed accurate determination of the flux conversion factors (FCF) for the 850 and 450 ?m arrays. Descriptions of the instrument beam shape and photometry methods are presented. The calibration factors are well determined, with relative calibration accuracy better than 5 per cent at 850 ?m and 10 per cent at 450 ?m, reflecting the success of the derived opacity relations as well as the stability of the performance of the instrument over several months. The sample size of the calibration observations and accurate FCFs have allowed the determination of the 850 and 450 ?m fluxes of several well-known submillimetre sources, and these results are compared with previous measurements from SCUBA.

  1. Design, manufacture, and calibration of infrared radiometric blackbody sources

    SciTech Connect

    Byrd, D.A.; Michaud, F.D.; Bender, S.C. [and others

    1996-04-01

    A Radiometric Calibration Station (RCS) is being assembled at the Los Alamos National Laboratories (LANL) which will allow for calibration of sensors with detector arrays having spectral capability from about 0.4-15 {mu}m. The configuration of the LANL RCS. Two blackbody sources have been designed to cover the spectral range from about 3-15 {mu}m, operating at temperatures ranging from about 180-350 K within a vacuum environment. The sources are designed to present a uniform spectral radiance over a large area to the sensor unit under test. The thermal uniformity requirement of the blackbody cavities has been one of the key factors of the design, requiring less than 50 mK variation over the entire blackbody surface to attain effective emissivity values of about 0.999. Once the two units are built and verified to the level of about 100 mK at LANL, they will be sent to the National Institute of Standards and Technology (NIST), where at least a factor of two improvement will be calibrated into the blackbody control system. The physical size of these assemblies will require modifications of the existing NIST Low Background Infrared (LBIR) Facility. LANL has constructed a bolt-on addition to the LBIR facility that will allow calibration of our large aperture sources. Methodology for attaining the two blackbody sources at calibrated levels of performance equivalent to present state of the art will be explained in the following.

  2. A novel approach for absolute radar calibration: formulation and theoretical validation

    NASA Astrophysics Data System (ADS)

    Merker, C.; Peters, G.; Clemens, M.; Lengfeld, K.; Ament, F.

    2015-06-01

    The theoretical framework of a novel approach for absolute radar calibration is presented and its potential analysed by means of synthetic data to lay out a solid basis for future practical application. The method presents the advantage of an absolute calibration with respect to the directly measured reflectivity, without needing a previously calibrated reference device. It requires a setup comprising three radars: two devices oriented towards each other, measuring reflectivity along the same horizontal beam and operating within a strongly attenuated frequency range (e.g. K or X band), and one vertical reflectivity and drop size distribution (DSD) profiler below this connecting line, which is to be calibrated. The absolute determination of the calibration factor is based on attenuation estimates. Using synthetic, smooth and geometrically idealised data, calibration is found to perform best using homogeneous precipitation events with rain rates high enough to ensure a distinct attenuation signal (reflectivity above ca. 30 dBZ). Furthermore, the choice of the interval width (in measuring range gates) around the vertically pointing radar, needed for attenuation estimation, is found to have an impact on the calibration results. Further analysis is done by means of synthetic data with realistic, inhomogeneous precipitation fields taken from measurements. A calibration factor is calculated for each considered case using the presented method. Based on the distribution of the calculated calibration factors, the most probable value is determined by estimating the mode of a fitted shifted logarithmic normal distribution function. After filtering the data set with respect to rain rate and inhomogeneity and choosing an appropriate length of the considered attenuation path, the estimated uncertainty of the calibration factor is of the order of 1 to 11 %, depending on the chosen interval width. Considering stability and accuracy of the method, an interval of eight range gates on both sides of the vertically pointing radar is most appropriate for calibration in the presented setup.

  3. MODEL CALIBRATION REPORT FOR THE HOUSATONIC RIVER

    EPA Science Inventory

    The Model Calibration Report will present a comparison of the model calibration runs to existing data for the calibration period, over a two year time frame. In addition, the model predictions for the calibration period will be compared to other supporting analyses, such as alter...

  4. Binocular Camera Calibration Using Rectification Error

    Microsoft Academic Search

    Derek Bradley; Wolfgang Heidrich

    2010-01-01

    Reprojection error is a commonly used measure for comparing the quality of different camera calibrations, for example when choosing the best calibration from a set. While this measure is suitable for single cameras, we show that we can improve calibrations in a binocular or multi-camera setup by calibrating the cameras in pairs using a rectification error. The rectification error determines

  5. Multiple Camera Types Simultaneous Stereo Calibration

    Microsoft Academic Search

    Guillaume Caron; Damien Eynard

    2011-01-01

    Calibration is a classical issue in computer vision needed to retrieve 3D information from image measurements. This work presents a calibration approach for hybrid stereo rig involving multiple central camera types (perspective, fisheye, catadioptric). The paper extends the method of monocular perspective camera calibration using virtual visual servoing. The simultaneous intrinsic and extrinsic calibration of central cameras rig, using different

  6. Single-Vector Calibration of Wind-Tunnel Force Balances

    NASA Technical Reports Server (NTRS)

    Parker, P. A.; DeLoach, R.

    2003-01-01

    An improved method of calibrating a wind-tunnel force balance involves the use of a unique load application system integrated with formal experimental design methodology. The Single-Vector Force Balance Calibration System (SVS) overcomes the productivity and accuracy limitations of prior calibration methods. A force balance is a complex structural spring element instrumented with strain gauges for measuring three orthogonal components of aerodynamic force (normal, axial, and side force) and three orthogonal components of aerodynamic torque (rolling, pitching, and yawing moments). Force balances remain as the state-of-the-art instrument that provide these measurements on a scale model of an aircraft during wind tunnel testing. Ideally, each electrical channel of the balance would respond only to its respective component of load, and it would have no response to other components of load. This is not entirely possible even though balance designs are optimized to minimize these undesirable interaction effects. Ultimately, a calibration experiment is performed to obtain the necessary data to generate a mathematical model and determine the force measurement accuracy. In order to set the independent variables of applied load for the calibration 24 NASA Tech Briefs, October 2003 experiment, a high-precision mechanical system is required. Manual deadweight systems have been in use at Langley Research Center (LaRC) since the 1940s. These simple methodologies produce high confidence results, but the process is mechanically complex and labor-intensive, requiring three to four weeks to complete. Over the past decade, automated balance calibration systems have been developed. In general, these systems were designed to automate the tedious manual calibration process resulting in an even more complex system which deteriorates load application quality. The current calibration approach relies on a one-factor-at-a-time (OFAT) methodology, where each independent variable is incremented individually throughout its full-scale range, while all other variables are held at a constant magnitude. This OFAT approach has been widely accepted because of its inherent simplicity and intuitive appeal to the balance engineer. LaRC has been conducting research in a "modern design of experiments" (MDOE) approach to force balance calibration. Formal experimental design techniques provide an integrated view to the entire calibration process covering all three major aspects of an experiment; the design of the experiment, the execution of the experiment, and the statistical analyses of the data. In order to overcome the weaknesses in the available mechanical systems and to apply formal experimental techniques, a new mechanical system was required. The SVS enables the complete calibration of a six-component force balance with a series of single force vectors.

  7. Social and Structural Factors Associated with HIV Infection among Female Sex Workers Who Inject Drugs in the Mexico-US Border Region

    PubMed Central

    Strathdee, Steffanie A.; Lozada, Remedios; Martinez, Gustavo; Vera, Alicia; Rusch, Melanie; Nguyen, Lucie; Pollini, Robin A.; Uribe-Salas, Felipe; Beletsky, Leo; Patterson, Thomas L.

    2011-01-01

    Background FSWs who inject drugs (FSW-IDUs) can acquire HIV through high risk sexual and injection behaviors. We studied correlates of HIV infection among FSW-IDUs in northern Mexico, where sex work is quasi-legal and syringes can be legally obtained without a prescription. Methods FSW-IDUs>18 years old who reported injecting drugs and recent unprotected sex with clients in Tijuana and Ciudad Juarez underwent surveys and HIV/STI testing. Logistic regression identified correlates of HIV infection. Results Of 620 FSW-IDUs, prevalence of HIV, gonorrhea, Chlamydia, trichomonas, syphilis titers ?1?8, or any of these infections was 5.3%, 4%, 13%, 35%, 10% and 72%, respectively. Compared to other FSW-IDUs, HIV-positive women were more likely to: have syphilis titers ?1?8 (36% vs. 9%, p<0.001), often/always inject drugs with clients (55% vs. 32%, p?=?0.01), and experience confiscation of syringes by police (49% vs. 28%, p?=?0.02). Factors independently associated with HIV infection were syphilis titers ?1?8, often/always injecting with clients and police confiscation of syringes. Women who obtained syringes from NEPs (needle exchange programs) within the last month had lower odds of HIV infection associated with active syphilis, but among non-NEP attenders, the odds of HIV infection associated with active syphilis was significantly elevated. Conclusions Factors operating in both the micro-social environment (i.e., injecting drugs with clients) and policy environment (i.e., having syringes confiscated by police, attending NEPs) predominated as factors associated with risk of HIV infection, rather than individual-level risk behaviors. Interventions should target unjustified policing practices, clients' risk behaviors and HIV/STI prevention through NEPs. PMID:21541349

  8. A novel approach for camera self-calibration from projective reconstruction

    NASA Astrophysics Data System (ADS)

    Yu, Haiyan; Qiao, Xiaolin; Wang, Jingyan; Yu, Haobo

    2007-06-01

    A novel approach for camera self-calibration is addressed in this paper. It is well known that one of problems for camera self-calibration is the matrix of the dual image of absolute conic (DIAC) is must positive definite. Then calibration matrix can be gotten by cholesky factorization from DIAC. In this paper, calibration matrix is directly optimized with nonlinear method which means that the solution of DIAC matrix is not necessary. It can help us avoid the positive definite problem. The algorithm builds on the basement of projective reconstruction, and it includes two steps. Firstly, the initial value of calibration matrix can be estimated from the manufacture explanation, then initial guess of infinity plane vector is searched out. Secondly, 8 parameters containing calibration matrix and infinity plane vector are optimized with Levenberg-Marquardt algorithm. Experiments validate the method.

  9. Calibrated Birth–Death Phylogenetic Time-Tree Priors for Bayesian Inference

    PubMed Central

    Drummond, Alexei J.

    2015-01-01

    Here we introduce a general class of multiple calibration birth–death tree priors for use in Bayesian phylogenetic inference. All tree priors in this class separate ancestral node heights into a set of “calibrated nodes” and “uncalibrated nodes” such that the marginal distribution of the calibrated nodes is user-specified whereas the density ratio of the birth–death prior is retained for trees with equal values for the calibrated nodes. We describe two formulations, one in which the calibration information informs the prior on ranked tree topologies, through the (conditional) prior, and the other which factorizes the prior on divergence times and ranked topologies, thus allowing uniform, or any arbitrary prior distribution on ranked topologies. Although the first of these formulations has some attractive properties, the algorithm we present for computing its prior density is computationally intensive. However, the second formulation is always faster and computationally efficient for up to six calibrations. We demonstrate the utility of the new class of multiple-calibration tree priors using both small simulations and a real-world analysis and compare the results to existing schemes. The two new calibrated tree priors described in this article offer greater flexibility and control of prior specification in calibrated time-tree inference and divergence time dating, and will remove the need for indirect approaches to the assessment of the combined effect of calibration densities and tree priors in Bayesian phylogenetic inference. PMID:25398445

  10. Barriers and Potential Improvements for Needle and Syringe Exchange Programs (NSPs) in China: A Qualitative Study from Perspectives of Both Health and Public Security Sectors

    PubMed Central

    Chow, Eric P. F.; Jing, Jun; Zheng, Jun; Zhao, Junshi; Zhang, Lei

    2015-01-01

    This study explores the acceptability, the barriers to the implementation of needle and syringe exchange programs (NSPs) and the potential improvement strategies in China from the perspectives of governmental health and public security officials. Purposive sampling was used for recruitment of participants who had been involved in NSPs implementation. Semi-Structured individual interviews were conducted in Mandarin to address three aspects of NSPs: (1) participants’ attitudes towards NSPs, (2) participants’ opinions on the effectiveness and barriers of NSPs, and (3) suggestions for improving the program. Content analysis was used to analyse the translated interview data. A total of 68 participants from 12 Hunan counties were interviewed (34 from each of the Bureau of Health and the Narcotic Division). Both groups recognised the importance and effectiveness of NSPs in HIV prevention, but public security officials regarded NSPs as a temporary intervention in place of punitive measures. Most health officials (32/34) regarded the main barriers to its implementation as administrative and structural, whereas participants from Narcotics Division (n=24) questioned the legitimacy of NSPs and concerned about the poor management of drug users’ risk behaviours. Close cooperation between the health and public security sectors, engagement of the drug user community and an enabling policy environment were reportedly to be critical for potential improvements of NSPs in China. Misconceptions about NSPs encourage drug users’ addictive behaviour, and an unclear leadership and insufficient support de-motivate the participants from the Bureau of Health and the Narcotics Division to actively support the program implementation. PMID:26114556

  11. Summary of AXAF calibration requirements

    NASA Technical Reports Server (NTRS)

    Kellogg, E.

    1993-01-01

    The following summarizes requirements on the High Resolution Mirror Assembly (HRMA) and HRMA/SI calibration. The lists of calibration measurements assume that the HRMA meets the CTT requirement that the XRCF test environment shall have not more than a 10 percent effect on the encircled energy in 1 arcsec and that it can be calibrated to 1 percent. This implies that the offloading scheme has been implemented in the HRMA. It should be remembered that there are additional calibrations needed for: aspect system; tracking; gyros; other parts of the PCAS; spacecraft timing and checks on timing accuracy for all SIs after integration in the spacecraft; ficucial lights and periscope; alignments; optical metrology data: lengths and diameters with errors on mirror elements and optical interferometer data on surface figure; and throughput and imaging stability test: an end-to-end test that can be used after the XRCF to verify that the x-ray throughput and imaging quality have not been degraded. The tables presented give a summary of the integration times for HRMA and HRMA/SI calibration.

  12. Self-calibrating multiplexer circuit

    DOEpatents

    Wahl, Chris P. (North Huntingdon, PA)

    1997-01-01

    A time domain multiplexer system with automatic determination of acceptable multiplexer output limits, error determination, or correction is comprised of a time domain multiplexer, a computer, a constant current source capable of at least three distinct current levels, and two series resistances employed for calibration and testing. A two point linear calibration curve defining acceptable multiplexer voltage limits may be defined by the computer by determining the voltage output of the multiplexer to very accurately known input signals developed from predetermined current levels across the series resistances. Drift in the multiplexer may be detected by the computer when the output voltage limits, expected during normal operation, are exceeded, or the relationship defined by the calibration curve is invalidated.

  13. Optimal calibration of nuclear instrumentation

    SciTech Connect

    Griffith, J.M.; Bray, M.A.; Feeley, J.J.

    1981-01-01

    Accurate knowledge of core power level is essential for the safe and efficient operation of nuclear power plants. Ionization chambers located outside the reactor core have the necessary reliability and response time characteristics and have been used extensively to indicate power level. The calibration of the ion chamber, and associated nuclear instrumentation (NI), has traditionally been based on the thermal power in the secondary coolant system. The usual NI calibration procedure consists of establishing steady-state operating conditions, calorimetrically determining the power at the secondary side of the steam generator, and adjusting the NI output to correspond to the measured thermal power. This study addresses certain questions including; (a) what sampling rate should be employed, (b) how many measurements are required, and (c) how can additional power level related information such as primary coolant loop measurements and knowledge of plant dynamics be included in the calibration procedure.

  14. Stable Calibration of Raman Lidar Water-Vapor Measurements

    NASA Technical Reports Server (NTRS)

    Leblanc, Thierry; McDermid, Iain S.

    2008-01-01

    A method has been devised to ensure stable, long-term calibration of Raman lidar measurements that are used to determine the altitude-dependent mixing ratio of water vapor in the upper troposphere and lower stratosphere. Because the lidar measurements yield a quantity proportional to the mixing ratio, rather than the mixing ratio itself, calibration is necessary to obtain the factor of proportionality. The present method involves the use of calibration data from two sources: (1) absolute calibration data from in situ radiosonde measurements made during occasional campaigns and (2) partial calibration data obtained by use, on a regular schedule, of a lamp that emits in a known spectrum determined in laboratory calibration measurements. In this method, data from the first radiosonde campaign are used to calculate a campaign-averaged absolute lidar calibration factor (t(sub 1)) and the corresponding campaign-averaged ration (L(sub 1)) between lamp irradiances at the water-vapor and nitrogen wavelengths. Depending on the scenario considered, this ratio can be assumed to be either constant over a long time (L=L(sub 1)) or drifting slowly with time. The absolutely calibrated water-vapor mixing ratio (q) obtained from the ith routine off-campaign lidar measurement is given by q(sub 1)=P(sub 1)/t(sub 1)=LP(sub 1)/P(sup prime)(sub 1) where P(sub 1) is water-vapor/nitrogen measurement signal ration, t(sub 1) is the unknown and unneeded overall efficiency ratio of the lidar receiver during the ith routine off-campaign measurement run, and P(sup prime)(sub 1) is the water-vapor/nitrogen signal ratio obtained during the lamp run associated with the ith routine off-campaign measurement run. If L is assumed constant, then the lidar calibration is routinely obtained without the need for new radiosonde data. In this case, one uses L=L(sub 1) = P(sup prime)(sub 1)/t(sub 1), where P(sub 1)(sup prime) is the water-vapor/nitrogen signal ratio obtained during the lamp run associated with the first radiosonde campaign. If L is assumed to drift slowly, then it is necessary to postpone calculation of a(sub 1) until after a second radiosonde campaign. In this case, one obtains a new value, L(sub 2), from the second radiosonde campaign, and for the ith routine off-campaign measurement run, one uses an intermediate value of L obtained by simple linear time interpolation between L(sub 1) and L(sub 2).

  15. Hypersonic Wind Tunnel Calibration Using the Modern Design of Experiments

    NASA Technical Reports Server (NTRS)

    Rhode, Matthew N.; DeLoach, Richard

    2005-01-01

    A calibration of a hypersonic wind tunnel has been conducted using formal experiment design techniques and response surface modeling. Data from a compact, highly efficient experiment was used to create a regression model of the pitot pressure as a function of the facility operating conditions as well as the longitudinal location within the test section. The new calibration utilized far fewer design points than prior experiments, but covered a wider range of the facility s operating envelope while revealing interactions between factors not captured in previous calibrations. A series of points chosen randomly within the design space was used to verify the accuracy of the response model. The development of the experiment design is discussed along with tactics used in the execution of the experiment to defend against systematic variation in the results. Trends in the data are illustrated, and comparisons are made to earlier findings.

  16. The KamLAND Full-Volume Calibration System

    SciTech Connect

    KamLAND Collaboration; Berger, B. E.; Busenitz, J.; Classen, T.; Decowski, M. P.; Dwyer, D. A.; Elor, G.; Frank, A.; Freedman, S. J.; Fujikawa, B. K.; Galloway, M.; Gray, F.; Heeger, K. M.; Hsu, L.; Ichimura, K.; Kadel, R.; Keefer, G.; Lendvai, C.; McKee, D.; O'Donnell, T.; Piepke, A.; Steiner, H. M.; Syversrud, D.; Wallig, J.; Winslow, L. A.; Ebihara, T.; Enomoto, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, K.; Owada, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Tamae, K.; Yoshida, S.; Kozlov, A.; Murayama, H.; Grant, C.; Leonard, D. S.; Luk, K.-B.; Jillings, C.; Mauger, C.; McKeown, R. D.; Zhang, C.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Pakvasa, S.; Foster, J.; Horton-Smith, G. A.; Tang, A.; Dazeley, S.; Downum, K. E.; Gratta, G.; Tolich, K.; Bugg, W.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Piquemal, F.; Ricol, J.-S.

    2009-03-05

    We have successfully built and operated a source deployment system for the KamLAND detector. This system was used to position radioactive sources throughout the delicate 1-kton liquid scintillator volume, while meeting stringent material cleanliness, material compatibility, and safety requirements. The calibration data obtained with this device were used to fully characterize detector position and energy reconstruction biases. As a result, the uncertainty in the size of the detector fiducial volume was reduced by a factor of two. Prior to calibration with this system, the fiducial volume was the largest source of systematic uncertainty in measuring the number of antineutrinos detected by KamLAND. This paper describes the design, operation and performance of this unique calibration system.

  17. Hepatitis C virus seroprevalence among people who inject drugs and factors associated with infection in eight Russian cities

    PubMed Central

    2014-01-01

    Background Behavioural surveillance among people who inject drugs (PWID) and testing for hepatitis C virus (HCV) and HIV is needed to understand the scope of both epidemics in at-risk populations and to suggest steps to improve their health. Methods PWID were recruited using respondent-driven sampling (RDS) in eight Russian cities. A standardized survey was administered to collect sociodemographic and behavioral information. Blood specimens were obtained for serological testing for HCV and HIV-1. Data across the eight sites were pooled to identify individual-, network-, and city-level factors associated with positive HCV serostatus. Results Among 2,596 PWID participating in the study, 1,837 tested positive for HCV (71%). The sample was 73% male and the mean age was 28. Very few PWID reported regular contact with harm reduction programs. Factors associated with testing positive for HCV were longer duration of injection drug use, testing positive for HIV-1, sharing non-syringe injection paraphernalia and water for rinsing syringes, and larger social network size. Factors negatively associated with HCV-positive serostatus were injecting with a used syringe and two city-level factors: longer mean RDS recruitment chain in a city and higher levels of injecting stimulants. Conclusions HCV prevalence in all eight Russian cities is at the higher end of the range of HCV prevalence among PWID in Europe, which provides evidence that more resources, better prevention programs, and accelerated treatment targeting PWID are needed to control the HCV epidemic. PMID:25253447

  18. Determination of priority phenolic pollutants exploiting an in-syringe dispersive liquid-liquid microextraction-multisyringe chromatography system.

    PubMed

    González, Alba; Avivar, Jessica; Cerdà, Víctor

    2015-03-01

    An automatic phenolic compounds analyzer is presented. The system performs online magnetic-stirring-assisted dispersive liquid-liquid microextraction before multisyringe chromatography (MSC) using a monolithic Chromolith Flash RP-18e column. The extraction behavior of the following phenolic pollutants: phenol, 2-nitrophenol, 4-nitrophenol, 2-chlorophenol, 2,4-diclorophenol, and 2,4,6-trichlorophenol, has been studied. A critical comparison of extractants (tributyl phosphate, acetonitrile, hexane, and 1-chlorobutane) and disperser solvents (acetone, acetonitrile, ethanol, methanol, 1-propanol, and 2-propanol) was made. Tributyl phosphate and acetonitrile were chosen as the extractant and the disperser solvent, respectively, since these showed the best performance. Phenols were online back-extracted into NaOH and neutralized before multi-isocratic chromatographic separation. The proposed analyzer can be applied for wide linear working ranges, i.e., between 40 and 20,000 ?g L(-1). The precision of the developed system has been proved, with maximum values for the intraday and interday precision of 4.4 % and 5.2 %, respectively, expressed as relative standard deviation, and high preconcentration factors (9.3-10.5) for most of the compounds studied. The method developed was successfully applied to natural water samples. PMID:25597789

  19. System for calibrating pressure transducer

    NASA Technical Reports Server (NTRS)

    Rollins, G. N. (inventor)

    1973-01-01

    A system for calibrating a pressure transducer which has a reference portion and an active portion is reported. A miniature selector valve is positioned immediately adjacent the pressure transducer. A reference pressure, known pressure, and unknown pressure can be selectively admitted to the active side of the pressure transducer by the selector valve to enable calibration of the transducer. A valve admits pressure to the selector valve which has a piston and floating piston arrangement which allows proper selection with very small linear movement.

  20. Mariner 9 television calibration - Revisited

    NASA Technical Reports Server (NTRS)

    Herkenhoff, Ken E.; Soderblom, Laurence A.; Murray, Bruce C.; Danielson, G. Edward

    1988-01-01

    Mariner 9 TV data from the 1971-1972 encounter with Mars, which contain good synoptic coverage of of the planet as well as the highest-resolution images thus far obtained for the south polar region, can lead to more accurate photometric analysis if subjected to improved processing methods. While calibration errors are rather greater than those of the Viking Orbiter cameras, both calibration data and processing software applicable to an improvement program have become available through the USGS's Planetary Image Cartography System.

  1. Accuracy testing of dose calibrators

    Microsoft Academic Search

    K. W. Logan; K. L. Blondeau; D. J. Widmer; R. A. Holmes

    1985-01-01

    Current methods for testing a dose calibrator's accuracy use measurements of ⁶°Co, ¹³⁷Cs, ⁵⁷Co, and ¹³³Ba sources but do not directly measure the accuracy of clinical radionuclides such as \\/sup 99m\\/Tc, ¹²³I, ¹¹¹In, ⁶⁷Ga, or ²°¹Tl. It is possible that some dose calibrators inaccurately determine the activity of these clinical radiopharmaceuticals. To correct this possible deficiency, the authors have devised

  2. Radiometric Calibration of Osmi Imagery Using Solar Calibration

    Microsoft Academic Search

    Dong-Han Lee; Yong-Seung Kim

    2000-01-01

    OSMI (Ocean Scanning Multi-Spectral Imager) raw image data (Level 0) were acquired and radiometrically corrected. We have applied two methods, using solar & dark calibration data from OSMI sensor and comparing with the SeaWiFS data, to the radiometric correction of OSMI raw image data. First, we could get the values of the gain and the offset for each pixel and

  3. IMU-Based Online Kinematic Calibration of Robot Manipulator

    PubMed Central

    2013-01-01

    Robot calibration is a useful diagnostic method for improving the positioning accuracy in robot production and maintenance. An online robot self-calibration method based on inertial measurement unit (IMU) is presented in this paper. The method requires that the IMU is rigidly attached to the robot manipulator, which makes it possible to obtain the orientation of the manipulator with the orientation of the IMU in real time. This paper proposed an efficient approach which incorporates Factored Quaternion Algorithm (FQA) and Kalman Filter (KF) to estimate the orientation of the IMU. Then, an Extended Kalman Filter (EKF) is used to estimate kinematic parameter errors. Using this proposed orientation estimation method will result in improved reliability and accuracy in determining the orientation of the manipulator. Compared with the existing vision-based self-calibration methods, the great advantage of this method is that it does not need the complex steps, such as camera calibration, images capture, and corner detection, which make the robot calibration procedure more autonomous in a dynamic manufacturing environment. Experimental studies on a GOOGOL GRB3016 robot show that this method has better accuracy, convenience, and effectiveness than vision-based methods. PMID:24302854

  4. IMU-based online kinematic calibration of robot manipulator.

    PubMed

    Du, Guanglong; Zhang, Ping

    2013-01-01

    Robot calibration is a useful diagnostic method for improving the positioning accuracy in robot production and maintenance. An online robot self-calibration method based on inertial measurement unit (IMU) is presented in this paper. The method requires that the IMU is rigidly attached to the robot manipulator, which makes it possible to obtain the orientation of the manipulator with the orientation of the IMU in real time. This paper proposed an efficient approach which incorporates Factored Quaternion Algorithm (FQA) and Kalman Filter (KF) to estimate the orientation of the IMU. Then, an Extended Kalman Filter (EKF) is used to estimate kinematic parameter errors. Using this proposed orientation estimation method will result in improved reliability and accuracy in determining the orientation of the manipulator. Compared with the existing vision-based self-calibration methods, the great advantage of this method is that it does not need the complex steps, such as camera calibration, images capture, and corner detection, which make the robot calibration procedure more autonomous in a dynamic manufacturing environment. Experimental studies on a GOOGOL GRB3016 robot show that this method has better accuracy, convenience, and effectiveness than vision-based methods. PMID:24302854

  5. ECC Ozonesonde Calibration and Observations: Satellite Validation

    NASA Technical Reports Server (NTRS)

    Schmidlin, Francis J.; Zukor, Dorothy (Technical Monitor)

    2001-01-01

    The reliability of the Electrochemical Concentration Cell (ECC) ozonesonde depends on the care exercised in preparing the instrument for use. Although the ECC can be quickly prepared and flown, generally within less then one day if necessary, it is best to prepare the instrument at least one week prior to use, and as our tests have confirmed even 2-3 weeks prior to use may actually be better. There are a number of factors that must be considered when preparing an ECC. These basically are the pump efficiency, volumetric flow rate, temperature of the air entering the pump, and the background current. Also of importance is the concentration of the potassium iodide solution. Tests conducted at Wallops Island (38 N) has enabled us to identify potential problem areas and ways to avoid them. The calibration and pre-flight preparation methods will be discussed. The method of calibrating the ECC also is used at Ascension Island (8 S) and Natal, Brazil (5 S). Comparisons between vertical profiles of the ECC instrument and satellites will be reviewed as well as comparison with ground based instruments, such as, the Dobson Spectrophotometer and hand held Microtops photometers.

  6. Study of self-calibrating MEMS accelerometers

    NASA Astrophysics Data System (ADS)

    Chen, Weiping; Li, Xiangyu; Liu, Xiaowei; Yin, Liang

    2015-04-01

    Micro-electromechanical System(MEMS) accelerometers are widely used in a number of inertial navigation systems and vibration detection system thanks to their small size, low cost and low power consumption. In order to improve their performance, the accelerometers have been designed to compensate the zero-bias caused by process variations. A new method of self-calibration sensitivity applies a self-test structure to simulate standard acceleration; depending on the standard and real-time values of the accelerometer's output and by adjustment of the time division feedback, the scale factor of capacitive accelerometers can be flexibly adjusted to achieve sensitivity in self-calibrating MEMS accelerometers. Moreover, this research also uses the following: a PID feedback structure to improve the stability of the closed-loop system; a correlated double sampling (CDS) circuit to attenuate noise, which can eliminate zero drift caused by offset voltage of the pre-amplifier; a time division multiplexing electrostatic force feedback circuit to achieve the operation of a closed-loop micro-accelerometer. The structure can completely avoid electrostatic feedback coupling with a capacitance change detection circuit, which can also improve the bandwidth and stability of the accelerometer. By means of capacitance compensation array the zero-bias performance of accelerometers can be improved. The bias stability of the accelerometer can be reduced from 173mg to 31mg by testing.

  7. Weighted least squares in calibration: estimating data variance functions in high-performance liquid chromatography.

    PubMed

    Zeng, Qiaoling Charlene; Zhang, Elizabeth; Dong, Hong; Tellinghuisen, Joel

    2008-10-10

    For minimum-variance estimation of parameters by the method of least squares, heteroscedastic data should be weighted inversely as their variance, w(i) proportional, variant 1/sigma(i)2. Here the instrumental data variance for a commercial high-performance liquid chromatography (HPLC) instrument is estimated from 5 to 11 replicate measurements on more than 20 samples for each of four different analytes. The samples span a range of over four orders of magnitude in concentration and HPLC peak area, over which the sampling variance estimates s2 are well represented as a sum of a constant term and a term proportional to the square of the peak area. The latter contribution is dominant over most of the range used in routine HPLC analysis and represents approximately 0.2% of peak area for all four analytes studied here. It includes a contribution from uncertainty in the syringe injection volume, which is found to be +/-0.008 microL. The dominance of proportional error justifies the use of 1/x2 or 1/y2 weighting in routine calibration with such data; however, the constant variance term means that these weighting formulas are not correct in the low-signal limit relevant for analysis at trace levels. Least-squares methods for both direct and logarithmic fitting of variance sampling estimates are described. Since such estimates themselves have proportional uncertainty, direct fitting requires iterative adjustment of the weights, while logarithmic fitting does not. PMID:18760790

  8. Photometric Redshift Calibration for LSST

    Microsoft Academic Search

    Samuel Schmidt; J. Newman; J. Tyson; A. Connolly; D. Wittman; D. Matthews; V. Margoniner; A. Choi; I. Udaltsova

    2009-01-01

    The proper calibration of photometric redshifts is of the utmost importance for the LSST, as many cosmological measurements depend critically on knowledge of the underlying redshift distribution. We examine how the use of different photometric redshift estimators affect the prediction of the photoz distribution. The great depth of LSST imaging will enable measurements of galaxies over a significant portion of

  9. Regional Location Calibration in Asia

    Microsoft Academic Search

    L. K. Steck; Hans Hartse; C. Aprea; J. Franks; Aaron Velasco; George Randall; C. Bradley; M. Begnaud; J. Aguilar-Chang

    2002-01-01

    This paper presents a spectrum of issues and efforts involved in improving seismic location performance worldwide. Our efforts are largely designed around providing validated, rigorously calibrated travel times, azimuths, and slownesses along with accurate error estimates. To do so entails a significant effort that includes data mining, data integration, database management, developing optimal 1-, 2-, and 3-D Earth models, using

  10. EVALUATION OF OZONE CALIBRATION PROCEDURES

    EPA Science Inventory

    In October of 1976, the U.S. Environmental Protection Agency announced that the calibration procedure then currently in use for reference methods for the measurement of ozone in the atmosphere -- the neutral buffered potassium iodide procedure -- had been found variable and in so...

  11. Recommended Inorganic Chemicals for Calibration.

    ERIC Educational Resources Information Center

    Moody, John R.; And Others

    1988-01-01

    All analytical techniques depend on the use of calibration chemicals to relate analyte concentration to instrumental parameters. Discusses the preparation of standard solutions and provides a critical evaluation of available materials. Lists elements by group and discusses the purity and uses of each. (MVL)

  12. 7, 81938260, 2007 Calibration and

    E-print Network

    Boyer, Edmond

    condensation nuclei counter (DMT-CCNC): CCN activation of ammonium sulfate and sodium chloride aerosol and calibration experiments with ammonium sulfate and sodium chloride aerosol5 particles in the diameter range to ±5­7%, which can15 be mostly attributed to variations of the CCNC column top temperature with ambient

  13. CALIBRATION OF SUBMERGED RADIAL GATES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calibration equations for free-flowing radial gates typically provide sufficient accuracy for irrigation district operations. However, many districts have difficulty in determining accurate discharges when the downstream water level begins to submerge the gate. Based on laboratory studies, we have d...

  14. Polarimetric calibration for RADARSAT-2

    Microsoft Academic Search

    A. P. Luscombe; Kancham Chotoo; B. D. Huxtable

    2000-01-01

    The RADARSAT-2 SAR currently under development will be required to operate in many modes, including a fully polarimetric mode with at least 30 beams. An efficient means for achieving and maintaining polarimetric calibration of these beams is needed, and the paper describes the work that has been performed to define and validate a method based on measurements obtained from polarimetric

  15. Reflection, Endorsement, Calibration Robert Stalnaker

    E-print Network

    Fitelson, Branden

    Reflection, Endorsement, Calibration Robert Stalnaker Bas van Fraassen's reflection principle has concern is not to defend the principle, but to reflect on the more general issue that the reflection of the reflection principle to a notorious example: the problem of Sleeping Beauty. #12;

  16. Sensitivity analysis of camera calibration

    Microsoft Academic Search

    Jan Heikkila

    1992-01-01

    To utilize the full potential of CCD cameras a careful design must be performed. The main contribution with respect to the final precision and reliability comes from the camera calibration. Both the precision of the estimated parameters or any functions of them (e.g., object coordinates) and the sensitivity of the system with respect to the undetected model errors are of

  17. Self-Calibrating Photometric Stereo

    Microsoft Academic Search

    Boxin Shi; Yasuyuki Matsushita; Yichen Wei; Chao Xu; Ping Tan

    2010-01-01

    We present a self-calibrating photometric stereo method. From a set of images taken from a fixed viewpoint under different and unknown lighting conditions, our method au- tomatically determines a radiometric response function and resolves the generalized bas-relief ambiguity for estimating accurate surface normals and albedos. We show that color and intensity profiles, which are obtained from registered pixels across images,

  18. Online stereo calibration using FPGAs

    Microsoft Academic Search

    Niklas Pettersson; Lars Petersson

    2005-01-01

    Online stereo calibration is useful in many situations where the cameras are moving relative to each other. The motion can either be intentional, as in an active stereo head, or due to vibrations, heat etc. which is commonly found in automotive applications. However, most approaches for finding the essential matrix relating the two cameras are computationally very expensive and, hence,

  19. INERTIAL MEASUREMENT UNIT CALIBRATION PLATFORM

    E-print Network

    Williams II, Robert L.

    , Parallel Robot, Carpal Wrist, Inertial Measurement Unit Calibration, Global Positioning System Contact Athens, OH 45701 Final Manuscript Journal of Robotic Systems June, 2000 Keywords: Platform Manipulator based on the parallel Carpal Wrist is under development for this task. High-accuracy positioning

  20. Autonomous Attitude Sensor Calibration (ASCAL)

    NASA Technical Reports Server (NTRS)

    Peterson, Chariya; Rowe, John; Mueller, Karl; Ziyad, Nigel

    1998-01-01

    In this paper, an approach to increase the degree of autonomy of flight software is proposed. We describe an enhancement of the Attitude Determination and Control System by augmenting it with self-calibration capability. Conventional attitude estimation and control algorithms are combined with higher level decision making and machine learning algorithms in order to deal with the uncertainty and complexity of the problem.

  1. Calibration of an anechoic room

    Microsoft Academic Search

    K. O. Ballagh

    1986-01-01

    A recently completed anechoic room with 100 m3 working space and 1 m long foam plastic wedges is described. An improved method of measuring the deviations from an ideal free field was used to calibrate the room. Within a 0.5 m radius of the source, the maximum deviation from a free field is 0.14 dB.

  2. ACS/WFC Postflash Calibration

    NASA Astrophysics Data System (ADS)

    Ogaz, Sara

    2013-10-01

    This program will be used to create the yearly post-flash calibration reference image. The format of these observations is slightly different from the reference file images taken last year in proposal 13166. It will contain 8 exposures with a post flash level of 2750 electrons.

  3. Usefulness of specific calibration coefficients for gamma-emitting sources measured by radionuclide calibrators in nuclear medicine

    SciTech Connect

    Bochud, Francois O.; Laedermann, Jean-Pascal; Baechler, Sebastien; Kosinski, Marek; Bailat, Claude J. [Institute of Radiation Physics, University Hospital and University of Lausanne, Rue du Grand-Pre 1, CH-1007 Lausanne (Switzerland)

    2011-07-15

    Purpose: In nuclear medicine, the activity of a radionuclide is measured with a radionuclide calibrator that often has a calibration coefficient independent of the container type and filling. Methods: To determine the effect of the container on the accuracy of measuring the activity injected into a patient, The authors simulated a commercial radionuclide calibrator and 18 container types most typically used in clinical practice. The instrument sensitivity was computed for various container thicknesses and filling levels. Monoenergetic photons and electrons as well as seven common radionuclides were considered. Results: The quality of the simulation with gamma-emitting sources was validated by an agreement with measurements better than 4% in five selected radionuclides. The results show that the measured activity can vary by more than a factor of 2 depending on the type of container. The filling level and the thickness of the container wall only have a marginal effect for radionuclides of high energy but could induce differences up to 4%. Conclusions: The authors conclude that radionuclide calibrators should be tailored to the uncertainty required by clinical applications. For most clinical cases, and at least for the low-energy gamma and x-ray emitters, measurements should be performed with calibration coefficients specific to the container type.

  4. Application of laser sensors for on-line calibration of displacement transducers

    NASA Astrophysics Data System (ADS)

    Xie, Jing; Gao, Hong-tang; Ye, Xiao-you; Gu, Feng-qiang; Li, Dong-sheng

    2010-08-01

    On-line calibration is widely used no matter in science research or industrial production. In this paper, an on-line calibration approach for industrial displacement transducers has been developed. We used laser displacement sensor as standard and improved its accuracy to meet the requirements in different applications. In order to achieve the objective, laser sensor must be calibrated by automatic interference comparator. Laser sensor and automatic interference comparator measured the same displacement simultaneously and obtained the laser displacement sensor's calibration curve by analyzing the measurement data. Then the on-line calibration system including mechanical device and calibration platform was developed with the calibrated laser sensor. Numerous factors, such as verticality, colors, reflector material and vibration, contribute to errors in the compact laser displacement sensor measurements under field conditions. Analyzing the data obtained from the device's application of air spring system in automatic interference comparator, the presented paper outlines the error compensation methods and mathematical model. Experimental results show that laser sensor on-line calibration system can solve factory calibrating problems with accuracy requirement over 0.3%.

  5. Optimized strategy for the calibration of superconducting gravimeters at the one per mille level

    NASA Astrophysics Data System (ADS)

    Van Camp, Michel; Meurers, Bruno; de Viron, Olivier; Forbriger, Thomas

    2015-04-01

    We investigate the causes of uncertainties on the amplitude calibration factor of a superconducting gravimeter determined by comparison with an absolute gravimeter (AG). This allows providing methods to mitigate those errors. We demonstrate that measuring for more than five days around a tidal extreme does not improve the precision in the calibration factor significantly, given the variability in the amplitude of the tidal signal. Restricting the AG measurements during tidal extrema reduce instrument wear, while this does not affect the precision on the calibration factor significantly. When the macroseismic noise is high, it causes aliasing in the AG time series; increasing the AG sampling rate then improves dramatically the determination of the calibration factor, rather than extending the measurement time. We also discuss the attenuation bias that might be induced by noisy time series of the superconducting gravimeter. If the standard deviation of the noise affecting the SG is at least 100 times lower than the standard deviation of the tidal signal used to compute the calibration factor, then the attenuation bias remains lower than the 0.1‰ level. Finally, if each experiment is performed at the 1‰ level, 7 are needed to ensure that the error in the calibration estimate will be at the 1 per mille level with a 99% confidence. This protocol may change in the future when atom AGs are easily available, as they should measure for several weeks without additional cost.

  6. 14 CFR 33.85 - Calibration tests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Block Tests; Turbine Aircraft Engines § 33.85 Calibration tests. (a) Each engine must be subjected to those calibration...

  7. 14 CFR 33.85 - Calibration tests.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Block Tests; Turbine Aircraft Engines § 33.85 Calibration tests. (a) Each engine must be subjected to those calibration...

  8. 14 CFR 33.85 - Calibration tests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Block Tests; Turbine Aircraft Engines § 33.85 Calibration tests. (a) Each engine must be subjected to those calibration...

  9. Calibration for Frequencies of Stellar Spectral Lines 

    E-print Network

    Gomez, Juana

    2010-07-14

    development is the use of laser frequency combs to provide the calibration frequencies. However, this approach is very time consuming and expensive. We are proposing a simple calibration approach using weak molecular absorption lines. Our new approach is based...

  10. Automated Attitude Sensor Calibration: Progress and Plans

    NASA Technical Reports Server (NTRS)

    Sedlak, Joseph; Hashmall, Joseph

    2004-01-01

    This paper describes ongoing work a NASA/Goddard Space Flight Center to improve the quality of spacecraft attitude sensor calibration and reduce costs by automating parts of the calibration process. The new calibration software can autonomously preview data quality over a given time span, select a subset of the data for processing, perform the requested calibration, and output a report. This level of automation is currently being implemented for two specific applications: inertial reference unit (IRU) calibration and sensor alignment calibration. The IRU calibration utility makes use of a sequential version of the Davenport algorithm. This utility has been successfully tested with simulated and actual flight data. The alignment calibration is still in the early testing stage. Both utilities will be incorporated into the institutional attitude ground support system.

  11. Radiometric calibration of Landsat Thematic Mapper

    Microsoft Academic Search

    G. E. Wukelic; D. E. Gibbons; L. M. Martucci; H. P. Foote

    1988-01-01

    Absolute calibration of satellite-acquired data is essential for quantification of scientific studies and a variety of image- processing applications. This paper describes a multiyear, on-orbit radiometric calibration of the Landsat Thematic Mapper (TM). Primary emphasis was placed on TM band 6 (thermal) calibration, but selected reflectance-band calibration measurements were also made. Twenty-five Landsat TM coverages were acquired, and included day,

  12. Application of PARAFAC for calibration with excitation-emission matrix fluorescence spectra of three classes of environmental pollutants

    Microsoft Academic Search

    Greger G. Andersson; Karl S. Booksh

    2000-01-01

    SUMMARY Parallel factor analysis (PARAFAC) is applied to three calibrations of a field-portable, cuvette-based, single- measurement, excitation-emission matrix fluorometer. In the first example the fluorometer is calibrated based on interactions between a non-fluorescent DDT-type pesticide and a fluorescent dye. PARAFAC is employed to deconvolve the fluorescence profiles of dissociated and complexed dye states. Calibration is performed based on the intensity

  13. Combining Scene and AutoCalibration Constraints

    Microsoft Academic Search

    David Liebowitz; Andrew Zisserman

    1999-01-01

    We present a simple approach to combining scene and auto-calibration constraints for the calibration of cameras from single views and stereo pairs. Calibration constraints are provided by imaged scene structure, such as vanish- ing points of orthogonal directions, or rectified planes. In addition, constraints are available from the nature of the cameras and the motion between views. We formulate these

  14. Low redshift type 1a supernovae calibration

    NASA Astrophysics Data System (ADS)

    Prasad, V.

    2004-05-01

    The calibration of 20 supernovae discovered and observed by the Supernovae Cosmology Project and EROS collaboration in 1999 is described. Using novel calibration techniques, we calibrate the supernovae images in the Johnson-Cousins U, B, V, R and I bands at the 1% level.

  15. Improved automated electronic balance calibration program

    Microsoft Academic Search

    J. P. Clark; E. M. Frickey

    1995-01-01

    An improved automated electronic balance calibration and record system has been developed using a spread sheet to consolidate information required to calibrate electronic balances and satisfy requirements for traceability, validation and documentation. Several improvements have been made over an Epson HX-20{trademark} notebook computer-based balance calibration system, which was developed at the Savannah River Site in 1986 and used continuously since

  16. Novel statistical calibration method for laser scanners

    NASA Astrophysics Data System (ADS)

    Chen, Jerry X.; Yen, Yung-Tsai C.

    1998-10-01

    Calibration of laser scanner is usually a complicated procedure and is only carried out in the manufacture site. Here we report a new statistical calibration method that is simple and easy. It can be carried out in either customer or manufacture site. This new approach is much more accurate than the current factory calibration method.

  17. Water content reflectometer calibration, field versus laboratory

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For soils with large amounts of high-charge clays, site-specific calibrations for the newer permittivity probes that operate at lower frequencies, often have higher permittivity values than factory calibrations. The purpose of this study was to determine site-specific calibration of water content re...

  18. RADARSAT image quality and calibration — Update

    Microsoft Academic Search

    S. K Srivastava; R. K Hawkins; T. I Lukowski; B. T Banik; M Adamovic; W. C Jefferies

    1999-01-01

    This paper reviews image quality and radiometric calibration aspects of the first two years of operation of RADARSAT. This includes the calibration of almost all beams (a total of more than 25 beams when considering shifted positions of each of the Fine beams), and the stability and calibration accuracies achieved during the mission to date. The measurements show that the

  19. Calibration of detector sensitivity in positron cameras

    Microsoft Academic Search

    D. A. Chesler; C. W. Stearns

    1990-01-01

    An improved method for calibrating detector sensitivities in a positron camera has been developed. The calibration phantom is a cylinder of activity placed near the center of the camera and fully within the field of view. The calibration data are processed in such a manner that the following two important properties are achieved: (1) the estimate of detector sensitivity is

  20. Camera Self-Calibration: Theory and Experiments

    Microsoft Academic Search

    Olivier D. Faugeras; Quang-tuan Luong; Stephen J. Maybank

    1992-01-01

    The problem of finding the internal orientation of a camera (camera calibration) is extremely important for practical applications. In this paper a complete method for calibrating a camera is presented. In contrast with existing methods it does not require a calibration object with a known 3D shape. The new method requires only point matches from image sequences. It is shown,

  1. Lessons learned from MODIS calibration and characterization

    Microsoft Academic Search

    X. Xiong; W. Barnes; R. Murphy

    2002-01-01

    Complete and accurate spatial, spectral, and radiometric calibration and characterizations are extremely important for earth observing spectroradiometers and are often heavily involved in the process of instrument design, pre-launch testing, and on-orbit operation, thereby providing essential parameters for the calibration algorithms and the development of science products. In this presentation, we will provide an overview of the calibration and characterization

  2. Calibration Curves for Real-Time PCR

    Microsoft Academic Search

    K. Kay-Yin Lai; Linda Cook; Elizabeth M. Krantz; Lawrence Corey; Keith R. Jerome

    2005-01-01

    Background: Despite the increasing use of real-time PCR in the diagnosis and management of viral infec- tions, there are no published studies adequately ad- dressing the optimum number of calibrators, the num- ber of replicates of each calibrator, and the frequency with which calibration needs to be repeated. This study was designed to address these issues. Methods: Cycle threshold data

  3. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...this subpart may be used. (3) When calibrating the engine flywheel torque transducer, any lever arm used to convert a weight...system. (d) Calibrated resistors may not be used for engine flywheel torque transducer calibration, but may be used to span...

  4. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...this subpart may be used. (3) When calibrating the engine flywheel torque transducer, any lever arm used to convert a weight...system. (d) Calibrated resistors may not be used for engine flywheel torque transducer calibration, but may be used to span...

  5. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...this subpart may be used. (3) When calibrating the engine flywheel torque transducer, any lever arm used to convert a weight...system. (d) Calibrated resistors may not be used for engine flywheel torque transducer calibration, but may be used to span...

  6. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...this subpart may be used. (3) When calibrating the engine flywheel torque transducer, any lever arm used to convert a weight...system. (d) Calibrated resistors may not be used for engine flywheel torque transducer calibration, but may be used to span...

  7. 40 CFR 89.307 - Dynamometer calibration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...this subpart may be used. (3) When calibrating the engine flywheel torque transducer, any lever arm used to convert a weight...system. (d) Calibrated resistors may not be used for engine flywheel torque transducer calibration, but may be used to span...

  8. Supplemental material Humidity-isotope response calibration

    E-print Network

    Meskhidze, Nicholas

    Supplemental material Humidity-isotope response calibration Each individual analyzer needs [Aemisegger et al., 2012; Schmidt et al., 2010]. Without humidity calibration, varying humidity levels in the introduced air samples will introduce an artificial isotope signal. The humidity-isotope response calibration

  9. Low redshift type 1a supernovae calibration

    Microsoft Academic Search

    V. Prasad

    2004-01-01

    The calibration of 20 supernovae discovered and observed by the Supernovae Cosmology Project and EROS collaboration in 1999 is described. Using novel calibration techniques, we calibrate the supernovae images in the Johnson–Cousins U, B, V, R and I bands at the 1% level.

  10. The simple procedure for the fluxgate magnetometers calibration

    NASA Astrophysics Data System (ADS)

    Marusenkov, Andriy

    2014-05-01

    The fluxgate magnetometers are widely used in geophysics investigations including the geomagnetic field monitoring at the global network of geomagnetic observatories as well as for electromagnetic sounding of the Earth's crust conductivity. For solving these tasks the magnetometers have to be calibrated with an appropriate level of accuracy. As a particular case, the ways to satisfy the recent requirements to the scaling and orientation errors of 1-second INTERNAGNET magnetometers are considered in the work. The goal of the present study was to choose a simple and reliable calibration method for estimation of scale factors and angular errors of the three-axis magnetometers in the field. There are a large number of the scalar calibration methods, which use a free rotation of the sensor in the calibration field followed by complicated data processing procedures for numerical solution of the high-order equations set. The chosen approach also exploits the Earth's magnetic field as a calibrating signal, but, in contrast to other methods, the sensor has to be oriented in some particular positions in respect to the total field vector, instead of the sensor free rotation. This allows to use very simple and straightforward linear computation formulas and, as a result, to achieve more reliable estimations of the calibrated parameters. The estimation of the scale factors is performed by the sequential aligning of each component of the sensor in two positions: parallel and anti-parallel to the Earth's magnetic field vector. The estimation of non-orthogonality angles between each pair of components is performed after sequential aligning of the components at the angles +/- 45 and +/- 135 degrees of arc in respect to the total field vector. Due to such four positions approach the estimations of the non-orthogonality angles are invariant to the zero offsets and non-linearity of transfer functions of the components. The experimental justifying of the proposed method by means of the Coil Calibration system reveals, that the achieved accuracy (<0.04 % for scale factors and 0.03 degrees of arc for angle errors) is sufficient for many applications, particularly for satisfying the INTERMAGNET requirements to 1-second instruments.

  11. Improvement of Accuracy in Environmental Dosimetry by TLD Cards Using Three-dimensional Calibration Method

    PubMed Central

    HosseiniAliabadi, S. J.; Hosseini Pooya, S. M.; Afarideh, H.; Mianji, F.

    2015-01-01

    Introduction The angular dependency of response for TLD cards may cause deviation from its true value on the results of environmental dosimetry, since TLDs may be exposed to radiation at different angles of incidence from the surrounding area. Objective A 3D setting of TLD cards has been calibrated isotropically in a standard radiation field to evaluate the improvement of the accuracy of measurement for environmental dosimetry. Method Three personal TLD cards were rectangularly placed in a cylindrical holder, and calibrated using 1D and 3D calibration methods. Then, the dosimeter has been used simultaneously with a reference instrument in a real radiation field measuring the accumulated dose within a time interval. Result The results show that the accuracy of measurement has been improved by 6.5% using 3D calibration factor in comparison with that of normal 1D calibration method. Conclusion This system can be utilized in large scale environmental monitoring with a higher accuracy.

  12. Genetic Algorithm Calibration of Probabilistic Cellular Automata for Modeling Mining Permit Activity

    USGS Publications Warehouse

    Louis, S.J.; Raines, G.L.

    2003-01-01

    We use a genetic algorithm to calibrate a spatially and temporally resolved cellular automata to model mining activity on public land in Idaho and western Montana. The genetic algorithm searches through a space of transition rule parameters of a two dimensional cellular automata model to find rule parameters that fit observed mining activity data. Previous work by one of the authors in calibrating the cellular automaton took weeks - the genetic algorithm takes a day and produces rules leading to about the same (or better) fit to observed data. These preliminary results indicate that genetic algorithms are a viable tool in calibrating cellular automata for this application. Experience gained during the calibration of this cellular automata suggests that mineral resource information is a critical factor in the quality of the results. With automated calibration, further refinements of how the mineral-resource information is provided to the cellular automaton will probably improve our model.

  13. Updated Calibration and Backgrounds for the WFC3 IR Grisms

    NASA Astrophysics Data System (ADS)

    Pirzkal, Norbert; Brammer, Gabriel; Ryan, Russell E.

    2015-01-01

    We present new and improved calibration of the WFC IR (G102 and G141) grism mode. These new calibrations were generated by combining data obtained over six observing cycles and include a better sampling of the field of view. The result is a calibration of the spectral trace that has been improved to better than 0.1 detector pixel. A new fiducial wavelength reference spectrum is now used to calibrate the wavelength dispersion of the grisms and we show that the rms of the solution has been reduced to approximately 7 and 14 Angstrom for the G102 and G141 grisms, over the entire field of view. Overall, both the trace and wavelength calibration have been improved by about a factor of two and the G102 and G141 solutions are in better agreement at wavelengths where the two grisms overlap. We demonstrate that the grism calibration can be extrapolated for objects that are outside of the field of view but still result in dispersed spectra on the WFC3 detector.We also present new master sky images that can be used to improve the sky background subtraction from grism exposures. The individual components of the new background model include the zodiacal continuum and a strong He I emission line at 1.083 microns from the upper atmosphere. We find that fitting science exposures with a linear combination of these two background components enables modeling of the WFC3/IR grism background with an accuracy that is better than ~0.01 electrons/s/pix across the detector.

  14. Spectral calibration for convex grating imaging spectrometer

    NASA Astrophysics Data System (ADS)

    Zhou, Jiankang; Chen, Xinhua; Ji, Yiqun; Chen, Yuheng; Shen, Weimin

    2013-12-01

    Spectral calibration of imaging spectrometer plays an important role for acquiring target accurate spectrum. There are two spectral calibration types in essence, the wavelength scanning and characteristic line sampling. Only the calibrated pixel is used for the wavelength scanning methods and he spectral response function (SRF) is constructed by the calibrated pixel itself. The different wavelength can be generated by the monochromator. The SRF is constructed by adjacent pixels of the calibrated one for the characteristic line sampling methods. And the pixels are illuminated by the narrow spectrum line and the center wavelength of the spectral line is exactly known. The calibration result comes from scanning method is precise, but it takes much time and data to deal with. The wavelength scanning method cannot be used in field or space environment. The characteristic line sampling method is simple, but the calibration precision is not easy to confirm. The standard spectroscopic lamp is used to calibrate our manufactured convex grating imaging spectrometer which has Offner concentric structure and can supply high resolution and uniform spectral signal. Gaussian fitting algorithm is used to determine the center position and the Full-Width-Half-Maximum?FWHM?of the characteristic spectrum line. The central wavelengths and FWHMs of spectral pixels are calibrated by cubic polynomial fitting. By setting a fitting error thresh hold and abandoning the maximum deviation point, an optimization calculation is achieved. The integrated calibration experiment equipment for spectral calibration is developed to enhance calibration efficiency. The spectral calibration result comes from spectral lamp method are verified by monochromator wavelength scanning calibration technique. The result shows that spectral calibration uncertainty of FWHM and center wavelength are both less than 0.08nm, or 5.2% of spectral FWHM.

  15. Toward Millimagnitude Photometric Calibration (Abstract)

    NASA Astrophysics Data System (ADS)

    Dose, E.

    2014-12-01

    (Abstract only) Asteroid roation, exoplanet transits, and similar measurements will increasingly call for photometric precisions better than about 10 millimagnitudes, often between nights and ideally between distant observers. The present work applies detailed spectral simulations to test popular photometric calibration practices, and to test new extensions of these practices. Using 107 synthetic spectra of stars of diverse colors, detailed atmospheric transmission spectra computed by solar-energy software, realistic spectra of popular astronomy gear, and the option of three sources of noise added at realistic millimagnitude levels, we find that certain adjustments to current calibration practices can help remove small systematic errors, especially for imperfect filters, high airmasses, and possibly passing thin cirrus clouds.

  16. Big MACS: Accurate photometric calibration

    NASA Astrophysics Data System (ADS)

    Kelly, P. L.; von der Linden, A.; Applegate, D.; Allen, M.; Allen, S. W.; Burchat, P. R.; Burke, D. L.; Ebeling, H.; Capak, P.; Czoske, O.; Donovan, D.; Mantz, A.; Morris, R. G.

    2012-08-01

    Big MACS is a Python program that estimates an accurate photometric calibration from only an input catalog of stellar magnitudes and filter transmission functions. The user does not have to measure color terms which can be difficult to characterize. Supplied with filter transmission functions, Big MACS synthesizes an expected stellar locus for your data and then simultaneously solves for all unknown zeropoints when fitting to the instrumental locus. The code uses a spectroscopic model for the SDSS stellar locus in color-color space and filter functions to compute expected locus. The stellar locus model is corrected for Milky Way reddening. If SDSS or 2MASS photometry is available for stars in field, Big MACS can yield a highly accurate absolute calibration.

  17. Spinning angle optical calibration apparatus

    DOEpatents

    Beer, Stephen K. (Morgantown, WV); Pratt, II, Harold R. (Morgantown, WV)

    1991-01-01

    An optical calibration apparatus is provided for calibrating and reproducing spinning angles in cross-polarization, nuclear magnetic resonance spectroscopy. An illuminated magnifying apparatus enables optical setting an accurate reproducing of spinning "magic angles" in cross-polarization, nuclear magnetic resonance spectroscopy experiments. A reference mark scribed on an edge of a spinning angle test sample holder is illuminated by a light source and viewed through a magnifying scope. When the "magic angle" of a sample material used as a standard is attained by varying the angular position of the sample holder, the coordinate position of the reference mark relative to a graduation or graduations on a reticle in the magnifying scope is noted. Thereafter, the spinning "magic angle" of a test material having similar nuclear properties to the standard is attained by returning the sample holder back to the originally noted coordinate position.

  18. Calibration Fixture For Welding Robot

    NASA Technical Reports Server (NTRS)

    Holly, Krisztina J.

    1990-01-01

    Compact, lightweight device used in any position or orientation. Calibration fixture designed for use on robotic gas/tungsten-arc welding torch equipped with vision-based seam-tracking system. Through optics in hollow torch cylinder, video camera obtains image of weld, viewing along line of sight coaxial with welding electrode. Attaches to welding-torch cylinder in place of gas cup normally attached in use. By use of longer or shorter extension tube, fixture accommodates welding electrode of unusual length.

  19. ASCAL: Autonomous Attitude Sensor Calibration

    NASA Technical Reports Server (NTRS)

    Peterson, Chariya; Rowe, John; Mueller, Karl; Ziyad, Nigel

    1999-01-01

    Abstract In this paper, an approach to increase the degree of autonomy of flight software is proposed. We describe an enhancement of the Attitude Determination and Control System by augmenting it with self-calibration capability. Conventional attitude estimation and control algorithms are combined with higher level decision making and machine learning algorithms in order to deal with the uncertainty and complexity of the problem.

  20. A Simple Calibrator for Noise Figure\\/Gain Meters

    Microsoft Academic Search

    1992-01-01

    The design and construction of a simple 10-100MHz noise figure and insertion gain calibrator is described. This instrument, constructed from readily available components, tests the accuracy of Y factor based noise figure measurement and insertion gain to better than 0.2dB over the full dynamic range of the target instrument, (usually ~50dB). The limitations of the method and the corrections applicable

  1. Pinhole Calibrator For Particle-Sizing Instrument

    NASA Technical Reports Server (NTRS)

    Hovenac, Edward

    1993-01-01

    Rotating-pinhole calibrator designed for use in calibrating and testing optical instrument measuring sizes of cloud droplets, dust particles, and other small particles suspended in flowing air. Easily attachable to particle-size-measuring instrument and suitable for both quick verification of calibration in field and detailed calibration studies in laboratory. Calibrator used to determine such operating parameters of instrument as optical collection angles, depth of field, profile of laser beam used to measure particles, and response to trajectory of particle. Also used to align instrument. Pinhole reused any number of times without risk of variation in diffraction pattern. Furthermore, size of pinhole chosen precisely and at will.

  2. Cross-calibration survey (VISNIR)

    NASA Technical Reports Server (NTRS)

    Bruegge, Carol J.

    1992-01-01

    Included in the summary of the VISNIR survey is (1) a statement of the preferred cross-calibration approach, as endorsed by select members of the VISNIR group, (2) two viewgraphs which summarize the wavelength and fields-of-view of the various instruments, and (3) a listing of these same data, as given by the respective calibration representatives in the survey responses. The Earth Observing System (EOS) Project is fundamentally committed to the acquisition of data which can be reduced to geophysical data products of high and known accuracy. One possible method of insuring the primary data products are of known accuracy is to use the instruments themselves against the same sources to provide an independent check that a common understanding of accuracy exists. The goal then of the radiometric 'Cross-Calibration' at the integrator facility (GE) would be to convincingly establish as late as feasible in the Integration and Test (I&T) cycle that, when stimulated with common sources, the appropriate EOS instrument measurements agree within their previously established accuracy estimates across a useful radiance range, accounting for the additional uncertainty associated with the unique properties of the test set-up itself.

  3. PACS photometer calibration block analysis

    NASA Astrophysics Data System (ADS)

    Moór, A.; Müller, T. G.; Kiss, C.; Balog, Z.; Billot, N.; Marton, G.

    2014-07-01

    The absolute stability of the PACS bolometer response over the entire mission lifetime without applying any corrections is about 0.5 % (standard deviation) or about 8 % peak-to-peak. This fantastic stability allows us to calibrate all scientific measurements by a fixed and time-independent response file, without using any information from the PACS internal calibration sources. However, the analysis of calibration block observations revealed clear correlations of the internal source signals with the evaporator temperature and a signal drift during the first half hour after the cooler recycling. These effects are small, but can be seen in repeated measurements of standard stars. From our analysis we established corrections for both effects which push the stability of the PACS bolometer response to about 0.2 % (stdev) or 2 % in the blue, 3 % in the green and 5 % in the red channel (peak-to-peak). After both corrections we still see a correlation of the signals with PACS FPU temperatures, possibly caused by parasitic heat influences via the Kevlar wires which connect the bolometers with the PACS Focal Plane Unit. No aging effect or degradation of the photometric system during the mission lifetime has been found.

  4. Model Calibration in Watershed Hydrology

    NASA Technical Reports Server (NTRS)

    Yilmaz, Koray K.; Vrugt, Jasper A.; Gupta, Hoshin V.; Sorooshian, Soroosh

    2009-01-01

    Hydrologic models use relatively simple mathematical equations to conceptualize and aggregate the complex, spatially distributed, and highly interrelated water, energy, and vegetation processes in a watershed. A consequence of process aggregation is that the model parameters often do not represent directly measurable entities and must, therefore, be estimated using measurements of the system inputs and outputs. During this process, known as model calibration, the parameters are adjusted so that the behavior of the model approximates, as closely and consistently as possible, the observed response of the hydrologic system over some historical period of time. This Chapter reviews the current state-of-the-art of model calibration in watershed hydrology with special emphasis on our own contributions in the last few decades. We discuss the historical background that has led to current perspectives, and review different approaches for manual and automatic single- and multi-objective parameter estimation. In particular, we highlight the recent developments in the calibration of distributed hydrologic models using parameter dimensionality reduction sampling, parameter regularization and parallel computing.

  5. Calibration Report for the WRAP Facility Gamma Energy Analysis System [104-ND-06-102A

    SciTech Connect

    WILLS, C.E.

    2000-02-15

    The Waste Receiving And Processing facility (WRAP) adheres to providing gamma-ray spectroscopy instrument calibrations traceable to the National Institute for Standards and Technology (NIST) standards. The detectors are used to produce quantitative results for the Waste Isolation Pilot Plant (WIPP) and must meet calibration programmatic calibration goals. Instruments must meet portions of ANSI N42.14, 1978 guide for Germanium detectors. The Non-Destructive Assay (NDA) Gamma Energy Analysis (GEA) utilizes NIST traceable line source standards for the detector system calibrations. The counting configuration is a series of drums containing the line sources and different density filler matrices. The drums are used to develop system efficiencies with respect to density. The efficiency and density correction factors are required for the processing of drummed waste materials of similar densities. The calibration verification is carried out after the calibration is deemed final, by counting a second drum of NIST traceable sources. Three in-depth calibrations have been completed on one of the two systems to date, the first being the system acceptance plan. This report has a secondary function; that being the development of the instrument calibration errors which are to be folded into the Total Instrument Uncertainty document, HNF-4050.

  6. Calibration Report for the WRAP Facility Gamma Energy Analysis System (104-ND-06-102A)

    SciTech Connect

    WILLS, C.E.

    2000-03-13

    The Waste Receiving And Processing facility (WRAP) adheres to providing gamma-ray spectroscopy instrument calibrations traceable to the National Institute for Standards and Technology (NIST) standard{sup (4)}. The detectors are used to produce quantitative results for the Waste Isolation Pilot Plant (WIPP) and must meet calibration programmatic calibration goals. Instruments must meet portions of ANSI N42.14, 1978 guide for Germanium detectors. The Non-Destructive Assay (NDA) Gamma Energy Analysis (GEA) utilizes NIST traceable line source standards for the detector system calibrations. The counting configuration is a series of drums containing the line sources and different density filler matrices. The drums are used to develop system efficiencies with respect to density. The efficiency and density correction factors are required for the processing of drummed waste materials of similar densities. The calibration verification is carried out after the calibration is deemed final, by counting a second drum of NIST traceable sources. Three in-depth calibrations have been completed on one of the two systems to date, the first being the system acceptance plan. This report has a secondary function; that being the development of the instrument calibration errors which are to be folded into the Total Instrument Uncertainty document, HNF-4050.

  7. GRAIN SIZING AND CALIBRATING OF DISTORTION BY IMAGE PROCESSING WITH INCLINED PHOTOGRAPH

    NASA Astrophysics Data System (ADS)

    Yasuda, Shingo; Ohashi, Keisuke; Ihara, Kazuki

    River bed material is normally heterogeneous, and the grain size distribution shows some features of each rivers. The information of distribution is, therefore, important factor in river engineering, and several traditional methods is practically used. Image processing method with digital photograph is modern analysis by using computer and replaced traditional analog photograph method. In image processing, however, optical distortion brings measurement error. We present a calibration of the distortion with optical theorem. In laboratory experiment with balls supposed river bed gravel, the theoretical calibration is considered to be appropriate. In field experiment, actual coefficient to calibrate distortion is estimated. In consequence of the investigation, it makes image processing method more accurate.

  8. Numerical Analysis of a Radiant Heat Flux Calibration System

    NASA Technical Reports Server (NTRS)

    Jiang, Shanjuan; Horn, Thomas J.; Dhir, V. K.

    1998-01-01

    A radiant heat flux gage calibration system exists in the Flight Loads Laboratory at NASA's Dryden Flight Research Center. This calibration system must be well understood if the heat flux gages calibrated in it are to provide useful data during radiant heating ground tests or flight tests of high speed aerospace vehicles. A part of the calibration system characterization process is to develop a numerical model of the flat plate heater element and heat flux gage, which will help identify errors due to convection, heater element erosion, and other factors. A 2-dimensional mathematical model of the gage-plate system has been developed to simulate the combined problem involving convection, radiation and mass loss by chemical reaction. A fourth order finite difference scheme is used to solve the steady state governing equations and determine the temperature distribution in the gage and plate, incident heat flux on the gage face, and flat plate erosion. Initial gage heat flux predictions from the model are found to be within 17% of experimental results.

  9. Calibration of a MOSFET Detection System for 6MV In Vivo Dosimetry

    Microsoft Academic Search

    Paolo Scalchi; P Francescon

    1998-01-01

    Purpose: Metal oxide semiconductor field-effect transistor (MOSFET) detectors were calibrated to perform in vivo dosimetry during 6-MV treatments, both in normal setup and total body irradiation (TBI) conditions.Methods and Materials: MOSFET water-equivalent depth, dependence of the calibration factors (CFs) on the field sizes, MOSFET orientation, bias supply, accumulated dose, incidence angle, temperature, and spoiler-skin distance in TBI setup were investigated.

  10. Improvement of MODIS RSB calibration by minimizing the Earthshine impact on solar diffuser observations

    Microsoft Academic Search

    X. Xie; X. Xiong; R. Wolfe; A. Lyapustin

    2006-01-01

    The MODerate Resolution Imaging Spectroraiometer (MODIS) reflective solar bands (RSB) are calibrated on-orbit using solar illuminations reflected from its onboard solar diffuser (SD) plate. The specified calibration uncertainty requirements for MODIS RSB are +\\/-2% in reflectance and +\\/-5% in radiance at their typical top of atmosphere (TOA) radiances. The onboard SD bi-directional reflectance factor (BRF) was characterized pre-launch by the

  11. Calibration of Antenna for EMI Measurements in Compact Semi-anechoic Rooms

    Microsoft Academic Search

    G. Betta; D. Capriglione; C. F. M. Carobbi; M. D. Migliore

    2008-01-01

    The accurate knowledge of the antenna factor is a fundamental requirement for reliable electromagnetic compatibility (EMC) measurements in emissions, immunity and human exposure tests. According to international standards, this would imply calibrating antennas in close-to-ideal test sites (calibration test sites), characterized by very large sizes of the ground plane and of the empty space volume above it (free-space behaviour). On

  12. Proton beam monitor chamber calibration.

    PubMed

    Gomà, C; Lorentini, S; Meer, D; Safai, S

    2014-09-01

    The first goal of this paper is to clarify the reference conditions for the reference dosimetry of clinical proton beams. A clear distinction is made between proton beam delivery systems which should be calibrated with a spread-out Bragg peak field and those that should be calibrated with a (pseudo-)monoenergetic proton beam. For the latter, this paper also compares two independent dosimetry techniques to calibrate the beam monitor chambers: absolute dosimetry (of the number of protons exiting the nozzle) with a Faraday cup and reference dosimetry (i.e. determination of the absorbed dose to water under IAEA TRS-398 reference conditions) with an ionization chamber. To compare the two techniques, Monte Carlo simulations were performed to convert dose-to-water to proton fluence. A good agreement was found between the Faraday cup technique and the reference dosimetry with a plane-parallel ionization chamber. The differences-of the order of 3%-were found to be within the uncertainty of the comparison. For cylindrical ionization chambers, however, the agreement was only possible when positioning the effective point of measurement of the chamber at the reference measurement depth-i.e. not complying with IAEA TRS-398 recommendations. In conclusion, for cylindrical ionization chambers, IAEA TRS-398 reference conditions for monoenergetic proton beams led to a systematic error in the determination of the absorbed dose to water, especially relevant for low-energy proton beams. To overcome this problem, the effective point of measurement of cylindrical ionization chambers should be taken into account when positioning the reference point of the chamber. Within the current IAEA TRS-398 recommendations, it seems advisable to use plane-parallel ionization chambers-rather than cylindrical chambers-for the reference dosimetry of pseudo-monoenergetic proton beams. PMID:25109620

  13. Proton beam monitor chamber calibration

    NASA Astrophysics Data System (ADS)

    Gomà, C.; Lorentini, S.; Meer, D.; Safai, S.

    2014-09-01

    The first goal of this paper is to clarify the reference conditions for the reference dosimetry of clinical proton beams. A clear distinction is made between proton beam delivery systems which should be calibrated with a spread-out Bragg peak field and those that should be calibrated with a (pseudo-)monoenergetic proton beam. For the latter, this paper also compares two independent dosimetry techniques to calibrate the beam monitor chambers: absolute dosimetry (of the number of protons exiting the nozzle) with a Faraday cup and reference dosimetry (i.e. determination of the absorbed dose to water under IAEA TRS-398 reference conditions) with an ionization chamber. To compare the two techniques, Monte Carlo simulations were performed to convert dose-to-water to proton fluence. A good agreement was found between the Faraday cup technique and the reference dosimetry with a plane-parallel ionization chamber. The differences—of the order of 3%—were found to be within the uncertainty of the comparison. For cylindrical ionization chambers, however, the agreement was only possible when positioning the effective point of measurement of the chamber at the reference measurement depth—i.e. not complying with IAEA TRS-398 recommendations. In conclusion, for cylindrical ionization chambers, IAEA TRS-398 reference conditions for monoenergetic proton beams led to a systematic error in the determination of the absorbed dose to water, especially relevant for low-energy proton beams. To overcome this problem, the effective point of measurement of cylindrical ionization chambers should be taken into account when positioning the reference point of the chamber. Within the current IAEA TRS-398 recommendations, it seems advisable to use plane-parallel ionization chambers—rather than cylindrical chambers—for the reference dosimetry of pseudo-monoenergetic proton beams.

  14. Weed Busters: Sprayer Calibration Guide

    E-print Network

    McGinty, Allan; Hanselka, C. Wayne; Lyons, Robert K.; Hart, Charles R.; Cadenhead, J. F.

    2005-03-07

    then add 1 quart of herbicide for every 15 gallons of spray in the tank. Keep these points in mind ?To properly calibrate a herbicide sprayer, you must be able to accurately set and maintain speed and pressure. ? Make sure all the nozzles are in good... condition and of the proper type. ?Never use a knife or other hard object to clean or clear clogged nozzles. ? Nozzles wear. Recalibrate sprayers often and replace nozzles when they become worn. ? Most nozzles used for broadcast herbicide applica- tions...

  15. SMAP RADAR Calibration and Validation

    NASA Astrophysics Data System (ADS)

    West, R. D.; Jaruwatanadilok, S.; Chaubel, J.

    2014-12-01

    The Soil Moisture Active Passive (SMAP) mission is planned to launch on Jan 8, 2015. The mission employs L-band radar and radiometer measurements to estimate soil moisture with 4% volumetric accuracy at a resolution of 10 km, and freeze-thaw state at a resolution of 1-3 km. Immediately following launch, there will be a 3 month instrument checkout period, followed by 6 months of level 1 (L1) calibration and validation. In this presentation, we will discuss the plans and preparations for the calibration and validation of L1 radar data from SMAP. At the start of the L1 cal/val period, we will validate the operation of the instrument and of the ground processing using tools that look at readily identifiable surface features such as coast lines and corner reflectors. Geometric biases will be fit and removed. Radiometric cross-calibration with PALSAR and Aquarius will also be performed using target regions in the Amazon rain forest selected for their stability and uniformity. As the L1 cal/val period progresses, the performance of the automated short and long term calibration modules in ground processing will be tracked and verified using data from stable reference targets such as the wind corrected ocean and selected areas of rain forest that have shown good temporal stability. The performance of the radio frequency interference (RFI) removal algorithm will be validated by processing data with the algorithm turned on and off, and using different parameter settings. Additional information on the extent of RFI will be obtained from a special RFI survey conducted early in the L1 cal/val period. Radar transmissions are turned off during the RFI survey, and receive only data are collected over a variety of operating frequencies. The model based Faraday rotation corrections will also be checked during the L1 cal/val by comparing the model Faraday rotation with the measured Faraday rotation obtained by the SMAP Radiometer. This work is supported by the SMAP project at the Jet Propulsion Laboratory, California Institute of Technology.

  16. Lidar calibration and extinction coefficients

    NASA Astrophysics Data System (ADS)

    Klett, J. D.

    1983-02-01

    Klett (1981) has presented an optical radar inversion scheme which utilizes only relative changes in the backscattered signal to produce estimates of atmospheric extinction as a function of range. It was also pointed out that better results could be obtained if use could be made of calibration information and/or other independent measurements to determine reference or boundary values of extinction sigma(m) more accurately. The present investigation is concerned with some characteristic features of a particular boundary value model for estimating sigma(m) based on knowledge of optical radar system constants, relative signal strength, and the relationship between the backscatter and extinction coefficients.

  17. NASA metrology and calibration, 1993

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Th sixteenth annual workshop of NASA's Metrology and Calibration Working Group was held April 20-22, 1993. The goals of the Working Group are to provide Agencywide standardization of individual metrology programs, where appropriate; to promote cooperation and exchange of information within NASA, with other Government agencies, and with industry; to serve as the primary Agency interface with the National Institute of Standards and Technology; and to encourage formal quality control techniques such as Measurement Assurance Programs. These proceedings contain unedited reports and presentations from the workshop and are provided for information only.

  18. Test on the reliability of gastight syringes as transfer/storage media for gaseous VOC analysis: the extent of VOC sorption between the inner needle and a glass wall surface.

    PubMed

    Kim, Yong-Hyun; Kim, Ki-Hyun

    2015-03-01

    A gastight syringe (GTS) is commonly used as a medium for transfer or storage of gaseous standards (or samples) in the analysis of volatile organic compounds (VOCs). In this study, the sorptive loss patterns of 21 VOCs were examined, using GTS as the transfer medium. The results of the test were evaluated with respect to a number of key variables including concentration, sampling volume, and physicochemical properties (molecular weight and boiling point). The VOCs with relatively high volatility (Group 1: aldehyde, ketone, ester, alcohol, and aromatic hydrocarbons (n = 12)) showed low sorptive losses with a mean (±SD) of 2.56 ± 2.87%, regardless of differences in the aforementioned key variables (p-value by t-test before and after using GTS = mean 0.15 ± 0.13). Conversely, the sorptive losses of seven semi-VOCs (Group 2: carboxyl and cresol (n = 9)) were significantly high, ranging from 18.0 ± 4.10% (propionic acid) to 65.4 ± 10.9% (n-heptanonic acid). In addition, we also measured the sorptive losses on the syringe needle (mean sorptive loss of Group 2 = 5.94 ± 5.63%). A linear regression analysis showed that the sorptive losses for Group 2 increased as molecular weight (or boiling point) increased, exhibiting a highly significant correlation (R(2) value (0.804 ± 0.084) and mean p-value (0.002 ± 0.003). PMID:25627703

  19. Ørsted pre-flight magnetometer calibration mission

    NASA Astrophysics Data System (ADS)

    Risbo, Torben; Brauer, Peter; Merayo, Jose M. G.; Nielsen, Otto V.; Petersen, Jan R.; Primdahl, Fritz; Richter, Ingo

    2003-05-01

    The compact spherical coil (CSC) vector-feedback magnetometer on the Danish Ørsted geomagnetic mapping satellite underwent extensive calibrations and verifications prior to integration and launch. The theory of the 'thin shell' calibration procedure is introduced. Spherical harmonic modelling was developed and tested over several years and used for Ørsted and other missions at test facilities in Europe, the United States and the Republic of South Africa. The verification of the test coil system using an Overhauser absolute scalar proton magnetometer is explained and the overall calibration results are given. The temperature calibrations are explained and reported on. The overall calibration model standard deviation is about 100 pT rms. Comparisons with the later in-flight calibrations show that, except for the unknown satellite offsets, an agreement within 4 nT was obtained. Finally an rf interference between the CSC and the Overhauser magnetometer is discussed, which may account for some of this discrepancy.

  20. Radio Interferometric Calibration Using The SAGE Algorithm

    E-print Network

    Sarod Yatawatta; Saleem Zaroubi; Ger de Bruyn; Leon Koopmans; Jan Noordam

    2008-10-31

    Radio Interferometry is an essential method for astronomical observations. Self-calibration techniques have increased the quality of the radio astronomical observations (and hence the science) by orders of magnitude. Recently, there is a drive towards sensor arrays built using inexpensive hardware and distributed over a wide area acting as radio interferometers. Calibration of such arrays poses new problems in terms of computational cost as well as in performance of existing calibration algorithms. We consider the application of the Space Alternating Generalized Expectation Maximization (SAGE) \\cite{Fess94} algorithm for calibration of radio interferometric arrays. Application to real data shows that this is an improvement over existing calibration algorithms that are based on direct, deterministic non linear optimization. As presented in this paper, we can improve the computational cost as well as the quality of the calibration using this algorithm.

  1. Atmospheric drag model calibrations for spacecraft lifetime prediction

    NASA Technical Reports Server (NTRS)

    Binebrink, A. L.; Radomski, M. S.; Samii, M. V.

    1989-01-01

    Although solar activity prediction uncertainty normally dominates decay prediction error budget for near-Earth spacecraft, the effect of drag force modeling errors for given levels of solar activity needs to be considered. Two atmospheric density models, the modified Harris-Priester model and the Jacchia-Roberts model, to reproduce the decay histories of the Solar Mesosphere Explorer (SME) and Solar Maximum Mission (SMM) spacecraft in the 490- to 540-kilometer altitude range were analyzed. Historical solar activity data were used in the input to the density computations. For each spacecraft and atmospheric model, a drag scaling adjustment factor was determined for a high-solar-activity year, such that the observed annual decay in the mean semimajor axis was reproduced by an averaged variation-of-parameters (VOP) orbit propagation. The SME (SMM) calibration was performed using calendar year 1983 (1982). The resulting calibration factors differ by 20 to 40 percent from the predictions of the prelaunch ballistic coefficients. The orbit propagations for each spacecraft were extended to the middle of 1988 using the calibrated drag models. For the Jaccia-Roberts density model, the observed decay in the mean semimajor axis of SME (SMM) over the 4.5-year (5.5-year) predictive period was reproduced to within 1.5 (4.4) percent. The corresponding figure for the Harris-Priester model was 8.6 (20.6) percent. Detailed results and conclusions regarding the importance of accurate drag force modeling for lifetime predictions are presented.

  2. Airborne lidar intensity calibration and application for land use classification

    NASA Astrophysics Data System (ADS)

    Li, Dong; Wang, Cheng; Luo, She-Zhou; Zuo, Zheng-Li

    2014-11-01

    Airborne Light Detection and Ranging (LiDAR) is an active remote sensing technology which can acquire the topographic information efficiently. It can record the accurate 3D coordinates of the targets and also the signal intensity (the amplitude of backscattered echoes) which represents reflectance characteristics of targets. The intensity data has been used in land use classification, vegetation fractional cover and leaf area index (LAI) estimation. Apart from the reflectance characteristics of the targets, the intensity data can also be influenced by many other factors, such as flying height, incident angle, atmospheric attenuation, laser pulse power and laser beam width. It is therefore necessary to calibrate intensity values before further applications. In this study, we analyze the factors affecting LiDAR intensity based on radar range equation firstly, and then applying the intensity calibration method, which includes the sensor-to-target distance and incident angle, to the laser intensity data over the study area. Finally the raw LiDAR intensity and normalized intensity data are used for land use classification along with LiDAR elevation data respectively. The results show that the classification accuracy from the normalized intensity data is higher than that from raw LiDAR intensity data and also indicate that the calibration of LiDAR intensity data is necessary in the application of land use classification.

  3. Self calibration of camera with non-linear imaging model

    NASA Astrophysics Data System (ADS)

    Hou, Wenguang; Shang, Tao; Ding, Mingyue

    2007-11-01

    Being put forward by the researchers in computer vision, self calibration commonly deals with camera with linear model. Since the distortion is practically existed especially for ordinary camera, the result of calibration can't meet the demand of vision measurement with high accuracy regardless of the distortion. Being obedience to systematism mainly, the distortion is the target function of distortion coefficient, principal point, principal distance ratio and skew factor etc. So there exists a group of parameters including of distortion coefficient, principal point, principal distance ratio and skew factor and fundamental matrix which make homologous point meets epipolar restriction theoretically. Accordingly, the paper advances the way titled self calibration of camera with non-linear imaging model which is on basis of the Kruppa equation. In calculating the fundamental matrix, we can obtain interior elements except principal distance by taking into account distortion correction about image coordinate. Then the principal distance can be obtained by using Kruppa equation. This way only need some homologous points between two images, not need any known information about objects. Lots of experiments have proven its correctness and reliability.

  4. A Summary of The 2000-2001 NASA Glenn Lear Jet AM0 Solar Cell Calibration Program

    NASA Technical Reports Server (NTRS)

    Scheiman, David; Brinker, David; Snyder, David; Baraona, Cosmo; Jenkins, Phillip; Rieke, William J.; Blankenship, Kurt S.; Tom, Ellen M.

    2002-01-01

    Calibration of solar cells for space is extremely important for satellite power system design. Accurate prediction of solar cell performance is critical to solar array sizing, often required to be within 1%. The NASA Glenn Research Center solar cell calibration airplane facility has been in operation since 1963 with 531 flights to date. The calibration includes real data to Air Mass (AM) 0.2 and uses the Langley plot method plus an ozone correction factor to extrapolate to AM0. Comparison of the AM0 calibration data indicates that there is good correlation with Balloon and Shuttle flown solar cells. This paper will present a history of the airplane calibration procedure, flying considerations, and a brief summary of the previous flying season with some measurement results. This past flying season had a record 35 flights. It will also discuss efforts to more clearly define the ozone correction factor.

  5. Robust weak-lensing mass calibration of Planck galaxy clusters

    NASA Astrophysics Data System (ADS)

    von der Linden, Anja; Mantz, Adam; Allen, Steven W.; Applegate, Douglas E.; Kelly, Patrick L.; Morris, R. Glenn; Wright, Adam; Allen, Mark T.; Burchat, Patricia R.; Burke, David L.; Donovan, David; Ebeling, Harald

    2014-09-01

    In light of the tension in cosmological constraints reported by the Planck team between their Sunyaev-Zel'dovich-selected cluster counts and Cosmic Microwave Background (CMB) temperature anisotropies, we compare the Planck cluster mass estimates with robust, weak-lensing mass measurements from the Weighing the Giants (WtG) project. For the 22 clusters in common between the Planck cosmology sample and WtG, we find an overall mass ratio of = 0.688 ± 0.072. Extending the sample to clusters not used in the Planck cosmology analysis yields a consistent value of = 0.698 ± 0.062 from 38 clusters in common. Identifying the weak-lensing masses as proxies for the true cluster mass (on average), these ratios are ˜1.6? lower than the default bias factor of 0.8 assumed in the Planck cluster analysis. Adopting the WtG weak-lensing-based mass calibration would substantially reduce the tension found between the Planck cluster count cosmology results and those from CMB temperature anisotropies, thereby dispensing of the need for `new physics' such as uncomfortably large neutrino masses (in the context of the measured Planck temperature anisotropies and other data). We also find modest evidence (at 95 per cent confidence) for a mass dependence of the calibration ratio and discuss its potential origin in light of systematic uncertainties in the temperature calibration of the X-ray measurements used to calibrate the Planck cluster masses. Our results exemplify the critical role that robust absolute mass calibration plays in cluster cosmology, and the invaluable role of accurate weak-lensing mass measurements in this regard.

  6. Calibration of the IMB Detector

    SciTech Connect

    Becker-Szendy, R.; Bionta, R.M.; Bratton, C.B.; Casper, D.; Claus, R.; Cortez, B.; Dye, S.T.; Errede, S.; Foster, G.W.; Gajewski, W.; Ganezer, K.; Goldhaber, M.; Haines, T.J.; Halverson, P.G.; Hazen, E.; Jones, T.W.; Kielczewska, D.; Kropp, W.R.; Learned, J.G.; Losecco, J.M.; Matsuno, S.; /UC, Irvine /Michigan U. /Brookhaven /Boston U. /Hawaii U. /University Coll. London /Warsaw U. /Cleveland State U. /Notre Dame U. /Louisiana State U. /Maryland U. /AT-T Bell Labs, Holmdel /Illinois U., Urbana /Fermilab /LLNL, Livermore /New Mexico U. /SLAC /Adelaide U. /CERN /Cal State, Dominguez Hills

    2012-04-03

    The IMB detector (named after its founding institutions: University of California, Irvine, the University of Michigan and Brookhaven National Laboratory) collected data on a wide range of phenomena for over eight years. It was the first and the largest of the ring imaging water Cherenkov detectors. The detector consisted of 8000 metric tons of ultra-pure water instrumented with 2048 photomultiplier tubes (PMTs). The PMTs were placed on the roof, floor, and walls of the detector in a lattice of approximately 1 m spacing. It made measurements of contained events that ranged in energy from 15 MeV up to 1.5 GeV. This paper describes the calibration of the IMB detector. This procedure was accurate and stable over a wide range of physical variables. It was used with little change throughout the entire eight-year lifetime of the experiment. The IMB calibration is a model for future large-scale detectors that employ the water Cherenkov technique.

  7. Crop physiology calibration in CLM

    NASA Astrophysics Data System (ADS)

    Bilionis, I.; Drewniak, B. A.; Constantinescu, E. M.

    2014-10-01

    Farming is using more terrestrial ground, as population increases and agriculture is increasingly used for non-nutritional purposes such as biofuel production. This agricultural expansion exerts an increasing impact on the terrestrial carbon cycle. In order to understand the impact of such processes, the Community Land Model (CLM) has been augmented with a CLM-Crop extension that simulates the development of three crop types: maize, soybean, and spring wheat. The CLM-Crop model is a complex system that relies on a suite of parametric inputs that govern plant growth under a given atmospheric forcing and available resources. CLM-Crop development used measurements of gross primary productivity and net ecosystem exchange from AmeriFlux sites to choose parameter values that optimize crop productivity in the model. In this paper we calibrate these parameters for one crop type, soybean, in order to provide a faithful projection in terms of both plant development and net carbon exchange. Calibration is performed in a Bayesian framework by developing a scalable and adaptive scheme based on sequential Monte Carlo (SMC).

  8. Evaluation of Calibration Laboratories Performance

    NASA Astrophysics Data System (ADS)

    Filipe, Eduarda

    2011-12-01

    One of the main goals of interlaboratory comparisons (ILCs) is the evaluation of the laboratories performance for the routine calibrations they perform for the clients. In the frame of Accreditation of Laboratories, the national accreditation boards (NABs) in collaboration with the national metrology institutes (NMIs) organize the ILCs needed to comply with the requirements of the international accreditation organizations. In order that an ILC is a reliable tool for a laboratory to validate its best measurement capability (BMC), it is needed that the NMI (reference laboratory) provides a better traveling standard—in terms of accuracy class or uncertainty—than the laboratories BMCs. Although this is the general situation, there are cases where the NABs ask the NMIs to evaluate the performance of the accredited laboratories when calibrating industrial measuring instruments. The aim of this article is to discuss the existing approaches for the evaluation of ILCs and propose a basis for the validation of the laboratories measurement capabilities. An example is drafted with the evaluation of the results of mercury-in-glass thermometers ILC with 12 participant laboratories.

  9. Oxygen-Mass-Flow Calibration Cell

    NASA Technical Reports Server (NTRS)

    Martin, Robert E.

    1996-01-01

    Proposed calibration standard for mass flow rate of oxygen based on conduction of oxygen ions through solid electrolyte membrane made of zirconia and heated to temperature of 1,000 degrees C. Flow of oxygen ions proportional to applied electric current. Unaffected by variations in temperature and pressure, and requires no measurement of volume. Calibration cell based on concept used to calibrate variety of medical and scientific instruments required to operate with precise rates of flow of oxygen.

  10. Absolute calibration of the Auger fluorescence detectors

    SciTech Connect

    Bauleo, P.; Brack, J.; Garrard, L.; Harton, J.; Knapik, R.; Meyhandan, R.; Rovero, A.C.; /Buenos Aires, IAFE; Tamashiro, A.; Warner, D.

    2005-07-01

    Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a light source at the telescope aperture. The technique accounts for the combined effects of all detector components in a single measurement. The calibrated 2.5 m diameter light source fills the aperture, providing uniform illumination to each pixel. The known flux from the light source and the response of the acquisition system give the required calibration for each pixel. In the lab, light source uniformity is studied using CCD images and the intensity is measured relative to NIST-calibrated photodiodes. Overall uncertainties are presently 12%, and are dominated by systematics.

  11. Calibration of the AXAF Observatory: Overview

    NASA Technical Reports Server (NTRS)

    Weisskopf, M.C.; ODell, S. L.

    1997-01-01

    The Advanced X-ray Astrophysics Facility (AXAF) will soon begin its exploration of the x-ray universe, providing unprecedented angular and spectral resolution. Also unprecedented is the ambitious goal of calibrating the AXAF observatory to an accuracy of a few percent. Toward this end, AXAF science and engineering teams undertook an extensive calibration program at component, subsystem, and system levels. This paper is an overview of the system-level calibration activities, conducted over the past year at the Marshall Space Flight Center (MSFC) X-Ray Calibration Facility (XRCF).

  12. FY2008 Calibration Systems Final Report

    SciTech Connect

    Cannon, Bret D.; Myers, Tanya L.; Broocks, Bryan T.

    2009-01-01

    The Calibrations project has been exploring alternative technologies for calibration of passive sensors in the infrared (IR) spectral region. In particular, we have investigated using quantum cascade lasers (QCLs) because these devices offer several advantages over conventional blackbodies such as reductions in size and weight while providing a spectral source in the IR with high output power. These devices can provide a rapid, multi-level radiance scheme to fit any nonlinear behavior as well as a spectral calibration that includes the fore-optics, which is currently not available for on-board calibration systems.

  13. 21 CFR 862.1150 - Calibrator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1150 Calibrator. (a) Identification. A...

  14. 21 CFR 862.1150 - Calibrator.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1150 Calibrator. (a) Identification. A...

  15. Status and development of the calibration programme

    NASA Astrophysics Data System (ADS)

    Doury, Benoit; Nikolova, Svetlana; Marty, Julien; Kramer, Alfred; Zampolli, Mario; Charbit, Maurice

    2015-04-01

    The objective of this poster is to present the status and latest achievements on the calibration of the IMS Seismic, Infrasound and Hydroacoustic stations. This includes PTS progress on scheduled calibration of IMS Seismic stations, the development and testing of a new calibration technique for Infrasound stations using a reference sensor and ambient noise, and related software developments. The poster will also describe PTS development axes and mid-term plan to fulfil the IMS Operational Manuals minimum requirements on the calibration of waveform stations.

  16. Spectral radiance source for vacuum ultraviolet calibrations

    NASA Astrophysics Data System (ADS)

    Sherrell, Fred G.

    1993-01-01

    A working standard extended source of spectral radiance has been assembled and calibrated for use in the 150- to 260-nm region. The assembly consists of a 10-kw, argon arc lamp mounted to irradiate a 4-in. diameter diffuser. The reflected energy from the diffuser is utilized as a calibration source. The procedure for calibrating the spectral radiance of the diffuser is reviewed. Traceability is accomplished by the use of a standard vacuum photodiode. The total uncertainty in the calibration of the source is estimated to be +/- 15 percent.

  17. Pressure Transducer Remote Calibration/Health Check

    NASA Technical Reports Server (NTRS)

    Deyoe, Richard; Voska, Ned (Technical Monitor)

    2002-01-01

    This presentation reports on efforts to develop an in-situ pressure transducer calibration system for extension of calibration lifecycle and transducer health determination. This system aims to: (1) provide a long term solution to determining the calibration of pressure transducers for gas applications, (2) provide a method of isolating problems in remote measurements, and (3) reduce costs and resources by extending the length of time a transducer may be left in a system without a repeat laboratory calibration. Topic covers include: design requirements, design assumptions and design approach.

  18. Research on vacuum utraviolet calibration technology

    NASA Astrophysics Data System (ADS)

    Wang, Jiapeng; Gao, Shumin; Sun, Hongsheng; Chen, Yinghang; Wei, Jianqiang

    2014-11-01

    Importance of extreme ultraviolet (EUV) and far ultraviolet (FUV) calibration is growing fast as vacuum ultraviolet payloads are wildly used in national space plan. A calibration device is established especially for the requirement of EUV and FUV metrology and measurement. Spectral radiation and detector relative spectral response at EUV and FUV wavelengths can be calibrated with accuracy of 26% and 20%, respectively. The setup of the device, theoretical model and value retroactive method are introduced and measurement of detector relative spectral response from 30 nm to 200 nm is presented in this paper. The calibration device plays an important role in national space research.

  19. Antarctic Mapping Project ACTIVE RADAR CALIBRATOR

    E-print Network

    Howat, Ian M.

    RADARSAT Antarctic Mapping Project ACTIVE RADAR CALIBRATOR INSTALLATION DOCUMENT October, 1999 CENTER #12;TABLE OF CONTENTS RADARSAT ANTARCTIC MAPPING PROJECT - ......................................................................................1 RADARSAT ARC OPERATION SCHEDULE

  20. Sloan Digital Sky Survey Photometric Calibration Revisited

    SciTech Connect

    Marriner, John; /Fermilab

    2012-06-29

    The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.

  1. Landsat TM and ETM+ Thermal Band Calibration

    NASA Technical Reports Server (NTRS)

    Barsi, Julia A.; Hook, Simon J.; Palluconi, Frank D.; Schott, John R.; Raqueno, Nina G.

    2006-01-01

    Landsat-5 Thematic Mapper (TM) has been imaging the Earth since March 1984 and Landsat-7 Enhanced Thematic Mapper Plus (ETM+) was added to the series of Landsat instruments in April 1999. The stability and calibration of the ETM+ has been monitored extensively since launch. Though not monitored for many years, TM now has a similar system in place to monitor stability and calibration. University teams have been evaluating the on-board calibration of the instruments through ground-based measurements since 1999. This paper considers the calibration efforts for the thermal band, Band 6, of both the Landsat-5 and Landsat-7 instruments.

  2. Radar Calibration Using a Student-Built Nanosatellite

    NASA Astrophysics Data System (ADS)

    Martin, L.; Fisher, N.; Jones, W.; Umeda, M.; Furumo, J.; Ah Heong, J.; Lim, T.; Shiroma, W.

    2011-09-01

    As a matter of national security, the US military must monitor and calibrate its 80+ C-band radar tracking stations on a consistent basis. These radar stations, which are distributed around the world, currently depend on two calibration satellites: RADCAL and DMSP F-15, launched in 1993 and 1999, respectively. Should either of these two satellites fail, the community of radar calibration users will no longer have a dependable means of calibration. Presented in this paper is the story behind a student-built satellite project, named Ho‘oponopono (“to make right” in the Hawaiian language), which is the first radar calibration satellite to take on a CubeSat form-factor. Led by a team of undergraduate and graduate students, this project has enabled its participants to reach their true potentials and thus act as a training ground for a class of highly competent, multi-tiered engineers. The management practices implemented throughout this project follow those used by today’s top defense contractors and engineering companies. Being involved in a project of this caliber, although time-consuming, provides the students with the experiences they need to make immediate and worthwhile contributions in today’s workforce. Juggling the multitude of commitments they have, however, makes it a challenge. Ho‘oponopono’s concept of operations calls for the collection and dissemination of ephemeris data, while simultaneously conducting transponder interrogations. After acquiring both sets of data, a radar station requesting calibration can then correlate the two and implement its calibration algorithms as needed. Ho‘oponopono and its mission were the basis for the University of Hawaii’s participation in the AFOSR University Nanosat-6 Program. After completing a rigorous two-year, six-level review process, we were awarded with the Most Improved and Third Place Awards at the January 2011 Flight Competition Review. Ho‘oponopono was also selected by NASA as a participant in its CubeSat Launch Initiative for an upcoming launch.

  3. Design and Calibration of a Cryogenic Blackbody Calibrator at Centimeter Wavelengths

    E-print Network

    A. Kogut; E. Wollack; D. J. Fixsen; M. Limon; P. Mirel; S. Levin; M. Seiffert; P. M. Lubin

    2004-02-24

    We describe the design and calibration of an external cryogenic blackbody calibrator used for the first two flights of the Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission (ARCADE) instrument. The calibrator consists of a microwave absorber weakly coupled to a superfluid liquid helium bath. Half-wave corrugations viewed 30 deg off axis reduce the return loss below -35 dB. Ruthenium oxide resistive thermometers embedded within the absorber monitor the temperature across the face of the calibrator. The thermal calibration transfers the calibration of a reference thermometer to the flight thermometers using the flight thermometer readout system. Data taken near the superfluid transition in 8 independent calibrations 4 years apart agree within 0.3 mK, providing an independent verification of the thermometer calibration at temperatures near that of the cosmic microwave background.

  4. Extrinsic calibration of a camera and laser range finder (improves camera calibration)

    Microsoft Academic Search

    Qilong Zhang; Robert Pless

    2004-01-01

    We describe theoretical and experimental results for the extrinsic calibration of sensor platform consisting of a camera and a 2D laser range finder. The calibration is based on observing a planar checkerboard pattern and solving for constraints between the \\

  5. In-flight calibration of the Cluster PEACE sensors

    NASA Astrophysics Data System (ADS)

    Doss, N.; Fazakerley, A. N.; Mihalj?i?, B.; Lahiff, A. D.; Wilson, R. J.; Kataria, D.; Rozum, I.; Watson, G.; Bogdanova, Y.

    2014-05-01

    The Plasma Electron and Current Experiment (PEACE) instruments operate on all four of the Cluster spacecraft and measure the 3-D velocity distribution of electrons in the energy range from 0.59 eV to 26.4 keV during each spacecraft spin. Pitch angle distributions and moments of the velocity distribution are also produced. As the mission has progressed, the efficiency of the detectors has declined. Several factors may play a role in this decline such as exposure to radiation, high electron fluxes and spacecraft thruster firings. To account for these variations, continuous in-flight calibration work is essential. The purpose of this paper is to describe the PEACE calibration parameters, focussing in particular on those that vary over time, and to describe the methods which are used to determine their evolution.

  6. Method and Apparatus for Accurately Calibrating a Spectrometer

    NASA Technical Reports Server (NTRS)

    Youngquist, Robert C. (Inventor); Simmons, Stephen M. (Inventor)

    2013-01-01

    A calibration assembly for a spectrometer is provided. The assembly includes a spectrometer having n detector elements, where each detector element is assigned a predetermined wavelength value. A first source emitting first radiation is used to calibrate the spectrometer. A device is placed in the path of the first radiation to split the first radiation into a first beam and a second beam. The assembly is configured so that one of the first and second beams travels a path-difference distance longer than the other of the first and second beams. An output signal is generated by the spectrometer when the first and second beams enter the spectrometer. The assembly includes a controller operable for processing the output signal and adapted to calculate correction factors for the respective predetermined wavelength values assigned to each detector element.

  7. Calibration of a diamagnetic diagnostic for stored energy of high-temperature electron annuli in Elmo Bumpy Torus (EBT)

    SciTech Connect

    Carpenter, K H; Dandl, R A; McGuffin, M W

    1982-05-01

    The perpendicular energy component of the stored energy of the electron annuli in ELMO Bumpy Torus (EBT) can be observed with diamagnetic flux detecting coils. The calibration of the signal from the coils in terms of stored energy requires a model for the geometrical structure of the annulus. Using a model of concentric cylindrical current sheets, the calibration factor for the diamagnetic perpendicular energy signal is derived, including the effects of drift currents and coupling of flux from adjacent annuli. Numerical calculations show the calibration factor to be insensitive to reasonable variations in the model parameters.

  8. Wide-area external multi-camera calibration using vision graphs and virtual calibration object

    Microsoft Academic Search

    Gregorij Kurillo; Zeyu Li; Ruzena Bajcsy

    2008-01-01

    In this paper we address external calibration of distributed multi-camera system intended for tracking and observing. We present a robust and efficient method for wide area calibration using virtual calibration object created by two LED markers. Our algorithm does not require for all the cameras to share common volume; only pairwise overlap is required. We assume the cameras are internally

  9. Calibration of of Sun Photometers and Sky Radiance Sensors. Chapter 3

    NASA Technical Reports Server (NTRS)

    Pietras, Christophe; Miller, Mark; Frouin, Robert; Eck, Tom; Holben, Brent; Marketon, John

    2001-01-01

    The main source of error in retrieving aerosol optical thicknesses using sun photometry comes from the determination of the TOA voltages. The degradation of interference filters is the most important source of the long-term changes in the cross-calibrations. Although major improvements have been made in the design of the filters (interference filters fabricated using ion-assisted deposition), the filters remain the principal factor limiting performance of the sun photometers. Degradation of filters necessitates frequent calibration of sun photometers and frequent measurements of the filter transmission or the relative system response. The degradation of the filters mounted on the CIMEL sun photometers have been monitored since 1993 by the Aerosol Robotic Network (AERONET) project. The decay reported by Holben et al. for the first two years of a CIMEL#s operation is between 1 and 5%. Nevertheless, the filters mounted on CIMEL instruments are regularly replaced after two years of use. The cross-calibration technique consists of taking measurements concurrently with the uncalibrated and the reference sun photometers. While analyzing measurements, the quality of the calibration has to be checked, using the following considerations: (1) any cirrus clouds suspected to be masking the sun, during the calibration period, need to be reported and the corresponding data set removed; and (2) the stability of the day needs to be checked. This chapter will describe calibration techniques, facilities, and protocols used for calibrating sun photometers and sky radiometers.

  10. Calibration of the NASA Glenn 8- by 6-Foot Supersonic Wind Tunnel (1996 and 1997 Tests)

    NASA Technical Reports Server (NTRS)

    Arrington, E. Allen

    2012-01-01

    There were several physical and operational changes made to the NASA Glenn Research Center 8- by 6-Foot Supersonic Wind Tunnel during the period of 1992 through 1996. Following each of these changes, a facility calibration was conducted to provide the required information to support the research test programs. Due to several factors (facility research test schedule, facility downtime and continued facility upgrades), a full test section calibration was not conducted until 1996. This calibration test incorporated all test section configurations and covered the existing operating range of the facility. However, near the end of that test entry, two of the vortex generators mounted on the compressor exit tailcone failed causing minor damage to the honeycomb flow straightener. The vortex generators were removed from the facility and calibration testing was terminated. A follow-up test entry was conducted in 1997 in order to fully calibrate the facility without the effects of the vortex generators and to provide a complete calibration of the newly expanded low speed operating range. During the 1997 tunnel entry, all planned test points required for a complete test section calibration were obtained. This data set included detailed in-plane and axial flow field distributions for use in quantifying the test section flow quality.

  11. Inspection of feasible calibration conditions for UV radiometer detectors with the KI/KIO3 actinometer.

    PubMed

    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. PMID:25283349

  12. An accurate system for onsite calibration of electronic transformers with digital output.

    PubMed

    Zhi, Zhang; Li, Hong-Bin

    2012-06-01

    Calibration systems with digital output are used to replace conventional calibration systems because of principle diversity and characteristics of digital output of electronic transformers. But precision and unpredictable stability limit their onsite application even development. So fully considering the factors influencing accuracy of calibration system and employing simple but reliable structure, an all-digital calibration system with digital output is proposed in this paper. In complicated calibration environments, precision and dynamic range are guaranteed by A/D converter with 24-bit resolution, synchronization error limit is nanosecond by using the novelty synchronization method. In addition, an error correction algorithm based on the differential method by using two-order Hanning convolution window has good inhibition of frequency fluctuation and inter-harmonics interference. To verify the effectiveness, error calibration was carried out in the State Grid Electric Power Research Institute of China and results show that the proposed system can reach the precision class up to 0.05. Actual onsite calibration shows that the system has high accuracy, and is easy to operate with satisfactory stability. PMID:22755666

  13. A Cryogenic Infrared Calibration Target

    NASA Technical Reports Server (NTRS)

    Wollack, E. J.; Kinzer, R. E., Jr.; Rinehart, S. A.

    2014-01-01

    A compact cryogenic calibration target is presented that has a peak diffuse reflectance, R < or = 0.003, from 800 to 4800/cm (12 - 2 microns ). Upon expanding the spectral range under consideration to 400-10,000/ cm-1 (25 - 1 microns) the observed performance gracefully degrades to R < or = 0.02 at the band edges. In the implementation described, a high-thermal-conductivity metallic substrate is textured with a pyramidal tiling and subsequently coated with a thin lossy dielectric coating that enables high absorption and thermal uniformity across the target. The resulting target assembly is lightweight, has a low-geometric profile, and has survived repeated thermal cycling from room temperature to approx.4 K. Basic design considerations, governing equations, and test data for realizing the structure described are provided. The optical properties of selected absorptive materials-Acktar Fractal Black, Aeroglaze Z306, and Stycast 2850 FT epoxy loaded with stainless steel powder-are characterized and presented

  14. Calibration of Irrigation Flow Meters.

    SciTech Connect

    Trimmer, Walter L.

    1988-02-01

    Several meters working on the Doppler principle were tested. The Doppler meters depend on reflections from particles or bubbles in the fluid to measure velocity. Although they were linear, they were too inaccurate and inconsistent. Two meters working on the transit time principle were tested and worked very well. These meters measure upstream and downstream transit times for signal reflections from the inner pipe surfaces. However this type of meter is available at present only for permanent installations, not as a survey meter. Finally, the currently used Hall meters were calibrated and recommendations were made as to their proper use. The report recommends that an effort be made to develop a transit time meter in a portable configuration for irrigation survey work. 14 figs., 5 tabs.

  15. Whistler and FLR density calibration

    NASA Astrophysics Data System (ADS)

    Lichtenberger, János; Vellante, Massimo; Heilig, Balázs; Ferencz, Csaba; Regi, Mauro; Clilverd, Mark; Juhász, Lilla

    2014-05-01

    One of the major objective in PLASMON (http://plasmon.elte.hu) project is to provide plasma densities for data assimilative modeling of plasmasphere from two ground based measurements: whistlers and field line resonances (FLRs). The whistler inversion method used in this procedure includes various model, including wave propagation, magnetic field, field aligned density distribution and equatorial electron density models. The latter one is a special one used for multiple-path whistler groups. As one can obtain electron densities from whistler inversion and plasma mass densities from FLRs, the ion composition would be required to connect the to dataset (that are intended to use in the plasmasphere model), which is rarely known or available. Therefore we have developed a method for cross calibration of the data from two sources. It is based on physics based and experimental field aligned plasma density distribution models as well as on comparison with in situ wave and density (IMAGE and Van Allen Probes) measurements.

  16. Gearbox Reliability Collaborative Bearing Calibration

    SciTech Connect

    van Dam, J.

    2011-10-01

    NREL has initiated the Gearbox Reliability Collaborative (GRC) to investigate the root cause of the low wind turbine gearbox reliability. The GRC follows a multi-pronged approach based on a collaborative of manufacturers, owners, researchers and consultants. The project combines analysis, field testing, dynamometer testing, condition monitoring, and the development and population of a gearbox failure database. At the core of the project are two 750kW gearboxes that have been redesigned and rebuilt so that they are representative of the multi-megawatt gearbox topology currently used in the industry. These gearboxes are heavily instrumented and are tested in the field and on the dynamometer. This report discusses the bearing calibrations of the gearboxes.

  17. Metrology - Beyond the Calibration Lab

    NASA Technical Reports Server (NTRS)

    Mimbs, Scott M.

    2008-01-01

    We rely on data from measurements every day; a gas-pump, a speedometer, and a supermarket weight scale are just three examples of measurements we use to make decisions. We generally accept the data from these measurements as "valid." One reason we can accept the data is the "legal metrology" requirements established and regulated by the government in matters of commerce. The measurement data used by NASA, other government agencies, and industry can be critical to decisions which affect everything from economic viability, to mission success, to the security of the nation. Measurement data can even affect life and death decisions. Metrology requirements must adequately provide for risks associated with these decisions. To do this, metrology must be integrated into all aspects of an industry including research, design, testing, and product acceptance. Metrology, the science of measurement, has traditionally focused on the calibration of instruments, and although instrument calibration is vital, it is only a part of the process that assures quality in measurement data. For example, measurements made in research can influence the fundamental premises that establish the design parameters, which then flow down to the manufacturing processes, and eventually impact the final product. Because a breakdown can occur anywhere within this cycle, measurement quality assurance has to be integrated into every part of the life-cycle process starting with the basic research and ending with the final product inspection process. The purpose of this paper is to discuss the role of metrology in the various phases of a product's life-cycle. For simplicity, the cycle will be divided in four broad phases, with discussions centering on metrology within NASA. .

  18. Uncertainty Analysis of Instrument Calibration and Application

    NASA Technical Reports Server (NTRS)

    Tripp, John S.; Tcheng, Ping

    1999-01-01

    Experimental aerodynamic researchers require estimated precision and bias uncertainties of measured physical quantities, typically at 95 percent confidence levels. Uncertainties of final computed aerodynamic parameters are obtained by propagation of individual measurement uncertainties through the defining functional expressions. In this paper, rigorous mathematical techniques are extended to determine precision and bias uncertainties of any instrument-sensor system. Through this analysis, instrument uncertainties determined through calibration are now expressed as functions of the corresponding measurement for linear and nonlinear univariate and multivariate processes. Treatment of correlated measurement precision error is developed. During laboratory calibration, calibration standard uncertainties are assumed to be an order of magnitude less than those of the instrument being calibrated. Often calibration standards do not satisfy this assumption. This paper applies rigorous statistical methods for inclusion of calibration standard uncertainty and covariance due to the order of their application. The effects of mathematical modeling error on calibration bias uncertainty are quantified. The effects of experimental design on uncertainty are analyzed. The importance of replication is emphasized, techniques for estimation of both bias and precision uncertainties using replication are developed. Statistical tests for stationarity of calibration parameters over time are obtained.

  19. Two-stage multiple cameras calibration

    Microsoft Academic Search

    Andrei Y. Kargashin; Eugeny I. Kugushev; E. L. Starostin

    1995-01-01

    The problem of determining spatial position and orientation of several cameras, knowing corresponding coordinates obtained by perspective projections onto the camera planes, is considered. Input data for calibration also include distances between some points in space. The calibration is carried out in two stages. In the first stage, position and orientation for pairs of images (stereo pairs) are determined. Every

  20. Accurate Camera Calibration with New Minimizing Function

    Microsoft Academic Search

    Qiaoyu Xu; Dong Ye; Rensheng Che; Yan Huang

    2006-01-01

    Camera calibration has been studied extensively in computer vision and photogrammetry. But almost all the camera calibration techniques iterate with the general minimizing function by minimizing the discrepancy between the real position in pixels of a 2D image point and the calculated projection of the 3D object point on the image plane. Though the imaging distance errors are equal, the

  1. Stereo Head Calibration from a Planar Object

    Microsoft Academic Search

    Henrik Malm; Anders Heyden

    2001-01-01

    A technique for stereo camera calibration from a known planar calibration object is proposed. Both the intrinsic parameters and the relative orientation are calculated. The proposed algorithm uses the two homogeneous linear constraints on the image of the absolute conic arising from the plane homographies for each camera and position. In addition to these, linear constraints on the relation between

  2. Method for calibration of plutonium NDA

    SciTech Connect

    Lemming, J.F.; Campbell, A.R.; Rodenburg, W.W.

    1980-01-01

    Calibration materials characterized by calorimetric assay can be a practical alternative to synthetic standards for the calibration of plutonium nondestructive assay. Calorimetric assay is an effective measurement system for the characterization because: it can give an absolute assay from first principles when the isotopic composition is known, it is insensitive to most matrix effects, and its traceability to international measurement systems has been demonstrated.

  3. Calibration and data quality of warm IRAC

    Microsoft Academic Search

    S. J. Carey; J. A. Surace; W. J. Glaccum; J. Ingalls; J. Krick; M. Lacy; P. Lowrance; S. Laine; J. O'Linger; J. R. Stauffer; S. P. Willner; J. L. Hora; W. F. Hoffmann; M. L. N. Ashby; J.-S. Huang; M. Marengo; M. Pahre; Z. Wang; M. Werner; G. G. Fazio

    2010-01-01

    We present an overview of the calibration and properties of data from the IRAC instrument aboard the Spitzer Space Telescope taken after the depletion of cryogen. The cryogen depleted on 15 May 2009, and shortly afterward a two-month- long calibration and characterization campaign was conducted. The array temperature and bias setpoints were revised on 19 September 2009 to take advantage

  4. Calibrating CAT bonds for Mexican earthquakes

    Microsoft Academic Search

    Wolfgang Härdle; Brenda López Cabrera

    2007-01-01

    The study of natural catastrophe models plays an important role in the prevention and mitigation of disasters. After the occurrence of a natural disaster, the reconstruction can be financed with catastrophe bonds (CAT bonds) or reinsurance. This paper examines the calibration of a real parametric CAT bond for earthquakes that was sponsored by the Mexican government. The calibration of the

  5. Gain calibration methods for radio telescope arrays

    Microsoft Academic Search

    Albert-Jan Boonstra; Alle-Jan van der Veen

    2003-01-01

    In radio telescope arrays, the complex receiver gains and sensor noise powers are initially unknown and have to be calibrated. Gain calibration can enhance the quality of astronomical sky images and, moreover, improve the effectiveness of array signal processing techniques for interference mitigation and spatial filtering. A challenging aspect is that the signal-to-noise ratio (SNR) is usually well below 0

  6. Virtual Reality Calibration for Telerobotic Servicing

    NASA Technical Reports Server (NTRS)

    Kim, W.

    1994-01-01

    A virtual reality calibration technique of matching a virtual environment of simulated graphics models in 3-D geometry and perspective with actual camera views of the remote site task environment has been developed to enable high-fidelity preview/predictive displays with calibrated graphics overlay on live video.

  7. A derivative standard for polarimeter calibration

    Microsoft Academic Search

    G. Mulhollan; J. Clendenin; P. Saez; D. Schultz; H. Tang; A. W. Pang; H. Hopster; K. Trantham; M. Johnston; T. Gay; B. Johnson; M. Magugumela; F. B. Dunning; G. K. Walters; G. F. Hanne

    1995-01-01

    A long-standing problem in polarized electron physics is the lack of a traceable standard for calibrating electron spin polarimeters. While several polarimeters are absolutely calibrated to better than 2%, the typical instrument has an inherent accuracy no better than 10%. This variability among polarimeters makes it difficult to compare advances in polarized electron sources between laboratories. We have undertaken an

  8. Cross-calibration between airborne SAR sensors

    NASA Technical Reports Server (NTRS)

    Zink, Manfred; Olivier, Philippe; Freeman, Anthony

    1993-01-01

    As Synthetic Aperture Radar (SAR) system performance and experience in SAR signature evaluation increase, quantitative analysis becomes more and more important. Such analyses require an absolute radiometric calibration of the complete SAR system. To keep the expenditure on calibration of future multichannel and multisensor remote sensing systems (e.g., X-SAR/SIR-C) within a tolerable level, data from different tracks and different sensors (channels) must be cross calibrated. The 1989 joint E-SAR/DC-8 SAR calibration campaign gave a first opportunity for such an experiment, including cross sensor and cross track calibration. A basic requirement for successful cross calibration is the stability of the SAR systems. The calibration parameters derived from different tracks and the polarimetric properties of the uncalibrated data are used to describe this stability. Quality criteria for a successful cross calibration are the agreement of alpha degree values and the consistency of radar cross sections of equally sized corner reflectors. Channel imbalance and cross talk provide additional quality in case of the polarimetric DC-8 SAR.

  9. ROBOT CALIBRATION USING LEAST-SQUARES AND

    E-print Network

    Flanagan, Randy

    ROBOT CALIBRATION USING LEAST-SQUARES AND P OLAR-DEC OMP O SITION FILTERING Gregory Ioannldes 1-axis robotic manipulators. The method proposed by the authors is based on a least-square estimation of the Yaskawa Motoman Robot was calibrated. The measurements of the Cartesian coordinates of points were

  10. Uncertainty and sensitivity analysis for camera calibration

    Microsoft Academic Search

    LiMin Zhu; HongGen Luo; Xu Zhang

    2009-01-01

    Purpose – The purpose of this paper is to present a unified approach to uncertainty and sensitivity analysis for camera calibration. Design\\/methodology\\/approach – The approach is based on the fact that camera calibration is a problem of parameter estimation and the parameters of interest are given by the optimal solution of a least-squares problem. Findings – A system of linear

  11. Regional calibration of a watershed model

    Microsoft Academic Search

    W. FERNANDEZ; R. M. VOGEL; A. SANKARASUBRAMANIAN

    As watershed models become increasingly sophisticated and useful, there is a need to extend their applicability to locations where they cannot be calibrated or validated. A new methodology for the regionalization of a watershed model is introduced and evaluated. The approach involves calibration of a watershed model to many sites in a region, concurrently. Previous research that has sought to

  12. Camera Calibration Using Two Concentric Circles

    Microsoft Academic Search

    Francisco Abad; Emilio Camahort; Roberto Vivó

    2004-01-01

    We present a simple calibration method for computing the extrinsic parameters (pose) and intrinsic parameters (focal length and principal point) of a camera by imaging a pattern of known geometry. Usually, the patterns used in calibration algorithms are complex to build (three orthogonal planes) or need a lot of features (checkerboard-like pat- tern). We propose using just two concentric circles

  13. Automatically controlled low temperature sensor calibration facility

    Microsoft Academic Search

    H. Demattio; K. D. Rusch; M. Süßer

    1994-01-01

    The present calibration facility has been modified during the last years. The existing measurement components such as digital multimeter, multiplexers, current sources and control system for temperature controlling have been replaced. All the necessary modes of operation are now controlled by a personal computer. Calibrations can be done in the temperature range from 1.5 to 300 K, but the range

  14. 3, 22432277, 2006 Fuzzy set calibration

    E-print Network

    Boyer, Edmond

    . 1 Introduction A large proportion of the world population is at risk of flooding and needs reliableHESSD 3, 2243­2277, 2006 Fuzzy set calibration of flood inundation models F. Pappenberger et al System Sciences Fuzzy set approach to calibrating distributed flood inundation models using remote

  15. Providing primary standard calibrations beyond 20 MHz

    NASA Astrophysics Data System (ADS)

    Bickley, C. J.; Zeqiri, B.; Robinson, S. P.

    2004-01-01

    The number of applications of medical ultrasound utilising frequencies in excess of 20 MHz has shown a consistent increase over recent years. Coupled with the commercial availability of wide-bandwidth hydrophones whose response extends beyond 40 MHz, this has driven a growing need to develop hydrophone calibration techniques at elevated frequencies. The current National Physical Laboratory primary standard method of calibrating hydrophones is based on an optical interferometer. This has been in operation for around 20 years and provides traceability over the frequency range of 0.3 to 20 MHz. More recently, calibrations carried out using the interferometer have been extended to 60 MHz, although the uncertainties associated with these calibrations are poor, being in excess of +/-20% at high frequencies. Major contributions to the degraded calibration uncertainties arise from poor signal-to-noise at higher frequencies, the frequency response of the photodiodes used and the noise floor of the instrument. To improve the uncertainty of hydrophone calibrations above 20 MHz, it has been necessary to build and commission a new interferometer. Important features of the new primary standard are its use of a higher power laser to improve the signal-to-noise ratio, along with photodiodes whose greater bandwidth to improve the overall frequency response. This paper describes the design of key aspects of the new interferometer. It also presents some initial results of the performance assessment, including a detailed comparison of calibrations of NPL reference membrane hydrophones, undertaken using old and new interferometers for calibration up to 40 MHz.

  16. Automatic alignment method for calibration of hydrometers

    Microsoft Academic Search

    Y. J. Lee; K. H. Chang; J. C. Chon; C. Y. Oh

    2004-01-01

    This paper presents a new method to automatically align specific scale-marks for the calibration of hydrometers. A hydrometer calibration system adopting the new method consists of a vision system, a stepping motor, and software to control the system. The vision system is composed of a CCD camera and a frame grabber, and is used to acquire images. The stepping motor

  17. Simplified stereo-optical ultrasound plane calibration

    NASA Astrophysics Data System (ADS)

    Hoßbach, Martin; Noll, Matthias; Wesarg, Stefan

    2013-03-01

    Image guided therapy is a natural concept and commonly used in medicine. In anesthesia, a common task is the injection of an anesthetic close to a nerve under freehand ultrasound guidance. Several guidance systems exist using electromagnetic tracking of the ultrasound probe as well as the needle, providing the physician with a precise projection of the needle into the ultrasound image. This, however, requires additional expensive devices. We suggest using optical tracking with miniature cameras attached to a 2D ultrasound probe to achieve a higher acceptance among physicians. The purpose of this paper is to present an intuitive method to calibrate freehand ultrasound needle guidance systems employing a rigid stereo camera system. State of the art methods are based on a complex series of error prone coordinate system transformations which makes them susceptible to error accumulation. By reducing the amount of calibration steps to a single calibration procedure we provide a calibration method that is equivalent, yet not prone to error accumulation. It requires a linear calibration object and is validated on three datasets utilizing di erent calibration objects: a 6mm metal bar and a 1:25mm biopsy needle were used for experiments. Compared to existing calibration methods for freehand ultrasound needle guidance systems, we are able to achieve higher accuracy results while additionally reducing the overall calibration complexity. Ke

  18. A Calibration Technique for Size Exclusion Chromatography

    Microsoft Academic Search

    R. D. Hester; P. H. Mitchell

    1984-01-01

    A modified Weibull distribution function is shown to be useful in calibrating the molecular size separation capabilities of both rigid and swellable gel packing materials. Two parameters are used in this function which are related to a packing material's micropore volume distribution. The calibration curves of a set of different packing materials connected in series were predicted from the Weibull

  19. Calibration strategies for the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Gaug, Markus; Berge, David; Daniel, Michael; Doro, Michele; Förster, Andreas; Hofmann, Werner; Maccarone, Maria C.; Parsons, Dan; de los Reyes Lopez, Raquel; van Eldik, Christopher

    2014-08-01

    The Central Calibration Facilities workpackage of the Cherenkov Telescope Array (CTA) observatory for very high energy gamma ray astronomy defines the overall calibration strategy of the array, develops dedicated hardware and software for the overall array calibration and coordinates the calibration efforts of the different telescopes. The latter include LED-based light pulsers, and various methods and instruments to achieve a calibration of the overall optical throughput. On the array level, methods for the inter-telescope calibration and the absolute calibration of the entire observatory are being developed. Additionally, the atmosphere above the telescopes, used as a calorimeter, will be monitored constantly with state-of-the-art instruments to obtain a full molecular and aerosol profile up to the stratosphere. The aim is to provide a maximal uncertainty of 10% on the reconstructed energy-scale, obtained through various independent methods. Different types of LIDAR in combination with all-sky-cameras will provide the observatory with an online, intelligent scheduling system, which, if the sky is partially covered by clouds, gives preference to sources observable under good atmospheric conditions. Wide-field optical telescopes and Raman Lidars will provide online information about the height-resolved atmospheric extinction, throughout the field-of-view of the cameras, allowing for the correction of the reconstructed energy of each gamma-ray event. The aim is to maximize the duty cycle of the observatory, in terms of usable data, while reducing the dead time introduced by calibration activities to an absolute minimum.

  20. Accurate size measurement of monosize calibration spheres by differential mobility analysis

    SciTech Connect

    Mulholland, George W.; Fernandez, Marco [Fire Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-0001 (United States)

    1998-11-24

    A differential mobility analyzer was used to measure the mean particle size of three monosize suspensions of polystyrene spheres in water. Key features of the experiment to minimize the uncertainty in the results include developing a recirculating flow to ensure equal flows into and out of the classifier, an accurate divider circuit for calibrating the electrode voltage, and use of the 100.7 nm NIST SRM for calibrating the flow of the classifier. The measured average sizes and expanded uncertainties with a coverage factor of 2 are 92.4 nm{+-}1.1 nm, 126.9 nm{+-}1.4 nm, and 217.7 nm{+-}3.4 nm. These calibration sizes were characterized by NIST to improve the calibration of scanning surface inspection systems.