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Sample records for tests accurately measure

  1. Measurement of testicular volume in smaller testes: how accurate is the conventional orchidometer?

    Science.gov (United States)

    Lin, Chih-Chieh; Huang, William J S; Chen, Kuang-Kuo

    2009-01-01

    The aim of this study was to evaluate the accuracy of different methods, including the Seager orchidometer (SO) and ultrasonography (US), for assessing testicular volume of smaller testes (testes volume less than 18 mL). Moreover, the equations used for the calculations--the Hansen formula (length [L] x width [W](2) x 0.52, equation A), the prolate ellipsoid formula (L x W x height [H] x 0.52, equation B), and the Lambert equation (L x W x H x 0.71, equation C)--were also examined and compared with the gold standard testicular volume obtained by water displacement (Archimedes principle). In this study, 30 testes from 15 men, mean age 75.3 (+/-8.3) years, were included. They all had advanced prostate cancer and were admitted for orchiectomy. Before the procedure, all the testes were assessed using SO and US. The dimensions were then input into each equation to obtain the volume estimates. The testicular volume by water displacement was 8.1 +/- 3.5 mL. Correlation coefficients (R(2)) of the 2 different methods (SO, US) to the gold standard were 0.70 and 0.85, respectively. The calculated testicular volumes were 9.2 +/- 3.9 mL (measured by SO, equation A), 11.9 +/- 5.2 mL (measured by SO, equation C), 7.3 +/- 4.2 mL (measured by US, equation A), 6.5 +/- 3.3 mL (measured by US, equation B) and 8.9 +/- 4.5 mL (measured by US, equation C). Only the mean size measured by US and volume calculated with the Hansen equation (equation A) and the mean size measured by US and volume calculated with the Lambert equation (equation C) showed no significant differences when compared with the volumes estimated by water displacement (mean difference 0.81 mL, P = .053, and 0.81 mL, P = .056, respectively). Based on our measurements, we categorized testicular volume by different cutoff values (7.0 mL, 7.5 mL, 8.0 mL, and 8.5 mL) to calculate a new constant for use in the Hansen equation. The new constant was 0.59. We then reexamined the equations using the new 0.59 constant, and found

  2. Non-destructive testing principles and accurate evaluation of the hydraulic measure impact range using the DC method

    Science.gov (United States)

    Qiu, Liming; Shen, Rongxi; Song, Dazhao; Wang, Enyuan; Liu, Zhentang; Niu, Yue; Jia, Haishan; Xia, Shankui; Zheng, Xiangxin

    2017-12-01

    An accurate and non-destructive evaluation method for the hydraulic measure impact range in coal seams is urgently needed. Aiming at the application demands, a theoretical study and field test are presented using the direct current (DC) method to evaluate the impact range of coal seam hydraulic measures. We firstly analyzed the law of the apparent resistivity response of an abnormal conductive zone in a coal seam, and then investigated the principle of non-destructive testing of the coal seam hydraulic measure impact range using the DC method, and used an accurate evaluation method based on the apparent resistivity cloud chart. Finally, taking hydraulic fracturing and hydraulic flushing as examples, field experiments were carried out in coal mines to evaluate the impact ranges. The results showed that: (1) in the process of hydraulic fracturing, coal conductivity was enhanced by high-pressure water in the coal seam, and after hydraulic fracturing, the boundary of the apparent resistivity decrease area was the boundary impact range. (2) In the process of hydraulic flushing, coal conductivity was reduced by holes and cracks in the coal seam, and after hydraulic flushing, the boundary of the apparent resistivity increase area was the boundary impact range. (3) After the implementation of the hydraulic measures, there may be some blind zones in the coal seam; in hydraulic fracturing blind zones, the apparent resistivity increased or stayed constant, while in hydraulic flushing blind zones, the apparent resistivity decreased or stayed constant. The DC method realized a comprehensive and non-destructive evaluation of the impact range of the hydraulic measures, and greatly reduced the time and cost of evaluation.

  3. Accurate thickness measurement of graphene

    International Nuclear Information System (INIS)

    Shearer, Cameron J; Slattery, Ashley D; Stapleton, Andrew J; Shapter, Joseph G; Gibson, Christopher T

    2016-01-01

    Graphene has emerged as a material with a vast variety of applications. The electronic, optical and mechanical properties of graphene are strongly influenced by the number of layers present in a sample. As a result, the dimensional characterization of graphene films is crucial, especially with the continued development of new synthesis methods and applications. A number of techniques exist to determine the thickness of graphene films including optical contrast, Raman scattering and scanning probe microscopy techniques. Atomic force microscopy (AFM), in particular, is used extensively since it provides three-dimensional images that enable the measurement of the lateral dimensions of graphene films as well as the thickness, and by extension the number of layers present. However, in the literature AFM has proven to be inaccurate with a wide range of measured values for single layer graphene thickness reported (between 0.4 and 1.7 nm). This discrepancy has been attributed to tip-surface interactions, image feedback settings and surface chemistry. In this work, we use standard and carbon nanotube modified AFM probes and a relatively new AFM imaging mode known as PeakForce tapping mode to establish a protocol that will allow users to accurately determine the thickness of graphene films. In particular, the error in measuring the first layer is reduced from 0.1–1.3 nm to 0.1–0.3 nm. Furthermore, in the process we establish that the graphene-substrate adsorbate layer and imaging force, in particular the pressure the tip exerts on the surface, are crucial components in the accurate measurement of graphene using AFM. These findings can be applied to other 2D materials. (paper)

  4. Test structures for accurate UHF C-V measurements of nano-scale CMOSFETs with HfSiON and TiN metal gate

    NARCIS (Netherlands)

    Lee, Kyong-Taek; Schmitz, Jurriaan; Brown, George A.; Heh, Dawei; Choi, Rino; Harris, Rusty; Song, Seung-Chul; Lee, Byoung Hun; Han, In-Sikh; Lee, Hi-Deok; Jeong, Yoon-Ha

    2007-01-01

    Test structures for accurate UHF capacitance –voltage (C-V) measurements of high performance CMOSFETs with Hf-based high-k dielectric and TiN metal gate are analyzed. It is shown that series resistance or substrate resistance between the channel region and body contact plays a role in UHF C-V

  5. Validity and reliability of the abdominal test and evaluation systems tool (ABTEST) to accurately measure abdominal force.

    Science.gov (United States)

    Glenn, Jordan M; Galey, Madeline; Edwards, Abigail; Rickert, Bradley; Washington, Tyrone A

    2015-07-01

    Ability to generate force from the core musculature is a critical factor for sports and general activities with insufficiencies predisposing individuals to injury. This study evaluated isometric force production as a valid and reliable method of assessing abdominal force using the abdominal test and evaluation systems tool (ABTEST). Secondary analysis estimated 1-repetition maximum on commercially available abdominal machine compared to maximum force and average power on ABTEST system. This study utilized test-retest reliability and comparative analysis for validity. Reliability was measured using test-retest design on ABTEST. Validity was measured via comparison to estimated 1-repetition maximum on a commercially available abdominal device. Participants applied isometric, abdominal force against a transducer and muscular activation was evaluated measuring normalized electromyographic activity at the rectus-abdominus, rectus-femoris, and erector-spinae. Test, re-test force production on ABTEST was significantly correlated (r=0.84; pactivity for the rectus-abdominus (72.93% and 75.66%), rectus-femoris (6.59% and 6.51%), and erector-spinae (6.82% and 5.48%) were observed for trial-1 and trial-2, respectively. Significant correlations for the estimated 1-repetition maximum were found for average power (r=0.70, p=0.002) and maximum force (r=0.72, pactivation of erector-spinae substantiates little subjective effort among participants in the lower back. Results suggest ABTEST is a valid and reliable method of evaluating abdominal force. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  6. A Small Area In-Situ MEMS Test Structure to Accurately Measure Fracture Strength by Electrostatic Probing

    Energy Technology Data Exchange (ETDEWEB)

    Bitsie, Fernando; Jensen, Brian D.; de Boer, Maarten

    1999-07-15

    We have designed, fabricated, tested and modeled a first generation small area test structure for MEMS fracture studies by electrostatic rather than mechanical probing. Because of its small area, this device has potential applications as a lot monitor of strength or fatigue of the MEMS structural material. By matching deflection versus applied voltage data to a 3-D model of the test structure, we develop high confidence that the local stresses achieved in the gage section are greater than 1 GPa. Brittle failure of the polycrystalline silicon was observed.

  7. Performance criteria for testosterone measurements based on biological variation in adult males: recommendations from the Partnership for the Accurate Testing of Hormones.

    Science.gov (United States)

    Yun, Yeo-Min; Botelho, Julianne Cook; Chandler, Donald W; Katayev, Alex; Roberts, William L; Stanczyk, Frank Z; Vesper, Hubert W; Nakamoto, Jon M; Garibaldi, Luigi; Clarke, Nigel J; Fitzgerald, Robert L

    2012-12-01

    Testosterone measurements that are accurate, reliable, and comparable across methodologies are crucial to improving public health. Current US Food and Drug Administration-cleared testosterone assays have important limitations. We sought to develop assay performance requirements on the basis of biological variation that allow physiologic changes to be distinguished from assay analytical errors. From literature review, the technical advisory subcommittee of the Partnership for the Accurate Testing of Hormones compiled a database of articles regarding analytical and biological variability of testosterone. These data, mostly from direct immunoassay-based methodologies, were used to specify analytical performance goals derived from within- and between-person variability of testosterone. The allowable limits of desirable imprecision and bias on the basis of currently available biological variation data were 5.3% and 6.4%, respectively. The total error goal was 16.7%. From recent College of American Pathologists proficiency survey data, most currently available testosterone assays missed these analytical performance goals by wide margins. Data from the recently established CDC Hormone Standardization program showed that although the overall mean bias of selected certified assays was within 6.4%, individual sample measurements could show large variability in terms of precision, bias, and total error. Because accurate measurement of testosterone across a wide range of concentrations [approximately 2-2000 ng/dL (0.069-69.4 nmol/L)] is important, we recommend using available data on biological variation to calculate performance criteria across the full range of expected values. Additional studies should be conducted to obtain biological variation data on testosterone from women and children, and revisions should be made to the analytical goals for these patient populations. © 2012 American Association for Clinical Chemistry

  8. Accurate Laser Measurements of the Water Vapor Self-Continuum Absorption in Four Near Infrared Atmospheric Windows. a Test of the MT_CKD Model.

    Science.gov (United States)

    Campargue, Alain; Kassi, Samir; Mondelain, Didier; Romanini, Daniele; Lechevallier, Loïc; Vasilchenko, Semyon

    2017-06-01

    The semi empirical MT_CKD model of the absorption continuum of water vapor is widely used in atmospheric radiative transfer codes of the atmosphere of Earth and exoplanets but lacks of experimental validation in the atmospheric windows. Recent laboratory measurements by Fourier transform Spectroscopy have led to self-continuum cross-sections much larger than the MT_CKD values in the near infrared transparency windows. In the present work, we report on accurate water vapor absorption continuum measurements by Cavity Ring Down Spectroscopy (CRDS) and Optical-Feedback-Cavity Enhanced Laser Spectroscopy (OF-CEAS) at selected spectral points of the transparency windows centered around 4.0, 2.1 and 1.25 μm. The temperature dependence of the absorption continuum at 4.38 μm and 3.32 μm is measured in the 23-39 °C range. The self-continuum water vapor absorption is derived either from the baseline variation of spectra recorded for a series of pressure values over a small spectral interval or from baseline monitoring at fixed laser frequency, during pressure ramps. In order to avoid possible bias approaching the water saturation pressure, the maximum pressure value was limited to about 16 Torr, corresponding to a 75% humidity rate. After subtraction of the local water monomer lines contribution, self-continuum cross-sections, C_{S}, were determined with a few % accuracy from the pressure squared dependence of the spectra base line level. Together with our previous CRDS and OF-CEAS measurements in the 2.1 and 1.6 μm windows, the derived water vapor self-continuum provides a unique set of water vapor self-continuum cross-sections for a test of the MT_CKD model in four transparency windows. Although showing some important deviations of the absolute values (up to a factor of 4 at the center of the 2.1 μm window), our accurate measurements validate the overall frequency dependence of the MT_CKD2.8 model.

  9. Apparatus for accurately measuring high temperatures

    Science.gov (United States)

    Smith, D.D.

    The present invention is a thermometer used for measuring furnace temperatures in the range of about 1800/sup 0/ to 2700/sup 0/C. The thermometer comprises a broadband multicolor thermal radiation sensor positioned to be in optical alignment with the end of a blackbody sight tube extending into the furnace. A valve-shutter arrangement is positioned between the radiation sensor and the sight tube and a chamber for containing a charge of high pressure gas is positioned between the valve-shutter arrangement and the radiation sensor. A momentary opening of the valve shutter arrangement allows a pulse of the high gas to purge the sight tube of air-borne thermal radiation contaminants which permits the radiation sensor to accurately measure the thermal radiation emanating from the end of the sight tube.

  10. Designing an accurate system for temperature measurements

    Directory of Open Access Journals (Sweden)

    Kochan Orest

    2017-01-01

    Full Text Available The method of compensation of changes in temperature field along the legs of inhomogeneous thermocouple, which measures a temperature of an object, is considered in this paper. This compensation is achieved by stabilization of the temperature field along the thermocouple. Such stabilization does not allow the error due to acquired thermoelectric inhomogeneity to manifest itself. There is also proposed the design of the furnace to stabilize temperature field along the legs of the thermocouple which measures the temperature of an object. This furnace is not integrated with the thermocouple mentioned above, therefore it is possible to replace this thermocouple with a new one when it get its legs considerably inhomogeneous.. There is designed the two loop measuring system with the ability of error correction which can use simultaneously a usual thermocouple as well as a thermocouple with controlled profile of temperature field. The latter can be used as a reference sensor for the former.

  11. Point of care testing provides an accurate measurement of creatinine, anion gap, and osmolal gap in ex-vivo whole blood samples with nitromethane.

    Science.gov (United States)

    Cao, D; Maynard, S; Mitchell, A M; Kerns, W P; Beuhler, M

    2014-07-01

    Nitromethane interferes with Jaffé measurements of creatinine, potentially mimicking acute kidney injury. We determined the proportional contribution of nitromethane in blood samples to creatinine measured by the Jaffé colorimetric and the point-of-care (POC) reactions and determined whether the difference can reliably estimate the concentration of nitromethane. Additionally, we determined whether the presence of nitromethane interferes with anion/osmolal gaps and ascertained the stability of nitromethane in serum after 7 days. Nitromethane was added to whole blood from four healthy volunteers to achieve concentrations of 0, 0.25, 0.5, 1, and 2 mmol/L. The following tests were performed: creatinine (Jaffé and POC), electrolytes (associated with Jaffé and POC), osmolality and nitromethane concentration (gas chromatography [GC]). Remaining samples were refrigerated and reanalyzed using GC at 7 days. Anion and osmolal gaps were calculated. Proportional recovery and degradation of nitromethane were measured using GC. Data were analyzed for agreement with single-factor ANOVA (p = 0.05). Mean creatinine for POC and Jaff methods were 0.93 vs. 0.76 mg/dL, respectively. Jaff creatinine concentrations increased linearly with increasing nitromethane concentrations (R(2) = 1, p = 0.01): measured creatinine (mg/dL) = 7.1*nitromethane (mmol/L) = 0.79. POC creatinine remained unchanged across the range of nitromethane concentrations (p = 0.99). Anion and osmolal gaps also remained unchanged. Nitromethane was reliably identified in all sample concentrations using GC on Day 0. Detection of 0.25 mmol/L nitromethane was not consistently recovered on Day 7. Nitromethane degradation was most pronounced at 2 mmol/L concentrations (81% recovery). Nitromethane alters apparent concentration of creatinine using the Jaffé reaction in a linear fashion but not when using the POC reaction. Measured difference between Jaffé and POC creatinine may identify the presence and estimate

  12. Accurate micro Hall effect measurements on scribe line pads

    DEFF Research Database (Denmark)

    Østerberg, Frederik Westergaard; Petersen, Dirch Hjorth; Wang, Fei

    2009-01-01

    be extracted from micro four-point measurements performed on a rectangular pad. The dimension of the investigated pad is 400 × 430 ¿m2, and the probe pitches range from 20 ¿m to 50 ¿m. The Monte Carlo method is used to find the optimal way to perform the Hall measurement and extract Hall mobility most......Hall mobility and sheet carrier density are important parameters to monitor in advanced semiconductor production. If micro Hall effect measurements are done on small pads in scribe lines, these parameters may be measured without using valuable test wafers. We report how Hall mobility can...... accurate in less than a minute. Measurements are performed on shallow trench isolation patterned silicon wafers to verify the results from the Monte Carlo method....

  13. ELF-test less accurately identifies liver cirrhosis diagnosed by liver stiffness measurement in non-Asian women with chronic hepatitis B

    NARCIS (Netherlands)

    Harkisoen, S.; Boland, G. J.; van den Hoek, J. A. R.; van Erpecum, K. J.; Hoepelman, A. I. M.; Arends, J. E.

    2014-01-01

    The enhanced liver fibrosis test (ELF-test) has been validated for several hepatic diseases. However, its performance in chronic hepatitis B virus (CHB) infected patients is uncertain. This study investigates the diagnostic value of the ELF test for cirrhosis identified by liver stiffness

  14. Bioaccessibility tests accurately estimate bioavailability of lead to quail

    Science.gov (United States)

    Beyer, W. Nelson; Basta, Nicholas T; Chaney, Rufus L.; Henry, Paula F.; Mosby, David; Rattner, Barnett A.; Scheckel, Kirk G.; Sprague, Dan; Weber, John

    2016-01-01

    Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, we measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison with blood Pb concentrations in quail fed a Pb acetate reference diet. Diets containing soil from five Pb-contaminated Superfund sites had relative bioavailabilities from 33%-63%, with a mean of about 50%. Treatment of two of the soils with phosphorus significantly reduced the bioavailability of Pb. Bioaccessibility of Pb in the test soils was then measured in six in vitro tests and regressed on bioavailability. They were: the “Relative Bioavailability Leaching Procedure” (RBALP) at pH 1.5, the same test conducted at pH 2.5, the “Ohio State University In vitro Gastrointestinal” method (OSU IVG), the “Urban Soil Bioaccessible Lead Test”, the modified “Physiologically Based Extraction Test” and the “Waterfowl Physiologically Based Extraction Test.” All regressions had positive slopes. Based on criteria of slope and coefficient of determination, the RBALP pH 2.5 and OSU IVG tests performed very well. Speciation by X-ray absorption spectroscopy demonstrated that, on average, most of the Pb in the sampled soils was sorbed to minerals (30%), bound to organic matter (24%), or present as Pb sulfate (18%). Additional Pb was associated with P (chloropyromorphite, hydroxypyromorphite and tertiary Pb phosphate), and with Pb carbonates, leadhillite (a lead sulfate carbonate hydroxide), and Pb sulfide. The formation of chloropyromorphite reduced the bioavailability of Pb and the amendment of Pb-contaminated soils with P may be a thermodynamically favored means to sequester Pb.

  15. New simple method for fast and accurate measurement of volumes

    International Nuclear Information System (INIS)

    Frattolillo, Antonio

    2006-01-01

    A new simple method is presented, which allows us to measure in just a few minutes but with reasonable accuracy (less than 1%) the volume confined inside a generic enclosure, regardless of the complexity of its shape. The technique proposed also allows us to measure the volume of any portion of a complex manifold, including, for instance, pipes and pipe fittings, valves, gauge heads, and so on, without disassembling the manifold at all. To this purpose an airtight variable volume is used, whose volume adjustment can be precisely measured; it has an overall capacity larger than that of the unknown volume. Such a variable volume is initially filled with a suitable test gas (for instance, air) at a known pressure, as carefully measured by means of a high precision capacitive gauge. By opening a valve, the test gas is allowed to expand into the previously evacuated unknown volume. A feedback control loop reacts to the resulting finite pressure drop, thus contracting the variable volume until the pressure exactly retrieves its initial value. The overall reduction of the variable volume achieved at the end of this process gives a direct measurement of the unknown volume, and definitively gets rid of the problem of dead spaces. The method proposed actually does not require the test gas to be rigorously held at a constant temperature, thus resulting in a huge simplification as compared to complex arrangements commonly used in metrology (gas expansion method), which can grant extremely accurate measurement but requires rather expensive equipments and results in time consuming methods, being therefore impractical in most applications. A simple theoretical analysis of the thermodynamic cycle and the results of experimental tests are described, which demonstrate that, in spite of its simplicity, the method provides a measurement accuracy within 0.5%. The system requires just a few minutes to complete a single measurement, and is ready immediately at the end of the process. The

  16. Accurate method of the magnetic field measurement of quadrupole magnets

    International Nuclear Information System (INIS)

    Kumada, M.; Sakai, I.; Someya, H.; Sasaki, H.

    1983-01-01

    We present an accurate method of the magnetic field measurement of the quadrupole magnet. The method of obtaining the information of the field gradient and the effective focussing length is given. A new scheme to obtain the information of the skew field components is also proposed. The relative accuracy of the measurement was 1 x 10 -4 or less. (author)

  17. BIOACCESSIBILITY TESTS ACCURATELY ESTIMATE BIOAVAILABILITY OF LEAD TO QUAIL

    Science.gov (United States)

    Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, we measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contami...

  18. Downhole temperature tool accurately measures well bore profile

    International Nuclear Information System (INIS)

    Cloud, W.B.

    1992-01-01

    This paper reports that an inexpensive temperature tool provides accurate temperatures measurements during drilling operations for better design of cement jobs, workovers, well stimulation, and well bore hydraulics. Valid temperature data during specific wellbore operations can improve initial job design, fluid testing, and slurry placement, ultimately enhancing well bore performance. This improvement applies to cement slurries, breaker activation for slurries, breaker activation for stimulation and profile control, and fluid rheological properties for all downhole operations. The temperature tool has been run standalone mounted inside drill pipe, on slick wire line and braided cable, and as a free-falltool. It has also been run piggyback on both directional surveys (slick line and free-fall) and standard logging runs. This temperature measuring system has been used extensively in field well bores to depths of 20,000 ft. The temperature tool is completely reusable in the field, ever similar to the standard directional survey tools used on may drilling rigs. The system includes a small, rugged, programmable temperature sensor, a standard body housing, various adapters for specific applications, and a personal computer (PC) interface

  19. Toward more accurate loss tangent measurements in reentrant cavities

    Energy Technology Data Exchange (ETDEWEB)

    Moyer, R. D.

    1980-05-01

    Karpova has described an absolute method for measurement of dielectric properties of a solid in a coaxial reentrant cavity. His cavity resonance equation yields very accurate results for dielectric constants. However, he presented only approximate expressions for the loss tangent. This report presents more exact expressions for that quantity and summarizes some experimental results.

  20. A Simple and Accurate Method for Measuring Enzyme Activity.

    Science.gov (United States)

    Yip, Din-Yan

    1997-01-01

    Presents methods commonly used for investigating enzyme activity using catalase and presents a new method for measuring catalase activity that is more reliable and accurate. Provides results that are readily reproduced and quantified. Can also be used for investigations of enzyme properties such as the effects of temperature, pH, inhibitors,…

  1. Device accurately measures and records low gas-flow rates

    Science.gov (United States)

    Branum, L. W.

    1966-01-01

    Free-floating piston in a vertical column accurately measures and records low gas-flow rates. The system may be calibrated, using an adjustable flow-rate gas supply, a low pressure gage, and a sequence recorder. From the calibration rates, a nomograph may be made for easy reduction. Temperature correction may be added for further accuracy.

  2. Truth in radiation: A matter of accurate measurement

    International Nuclear Information System (INIS)

    Gill, D.; Schutz, D.F.

    1990-01-01

    Radiation protection begins with accurate measurement. Without respect for radiation based on a solid scientific measurement free reign is given to those who would create harm through over exposures resulting from carelessness and apathy as well as to those who would deny the benefits of nuclear technology by seeking to eliminate all exposure to nuclear radiation. Teledyne Isotopes has been a leader in accurate radiation measurement since 1955, providing measurements of all significant radionuclides in environmental media from the vicinity of nuclear power plants, nuclear material production facilities and research facilities. TI also provides thermoluminescent dosimetry (TLD) for environmental radiation and human exposure monitoring. Instrumentation ranges from manual readers for small facilities and research applications to automatic readers for large-scale badge service operations

  3. A novel and accurate diagnostic test for human African trypanosomiasis.

    Science.gov (United States)

    Papadopoulos, Marios C; Abel, Paulo M; Agranoff, Dan; Stich, August; Tarelli, Edward; Bell, B Anthony; Planche, Timothy; Loosemore, Alison; Saadoun, Samira; Wilkins, Peter; Krishna, Sanjeev

    2004-04-24

    Human African trypanosomiasis (sleeping sickness) affects up to half a million people every year in sub-Saharan Africa. Because current diagnostic tests for the disease have low accuracy, we sought to develop a novel test that can diagnose human African trypanosomiasis with high sensitivity and specificity. We applied serum samples from 85 patients with African trypanosomiasis and 146 control patients who had other parasitic and non-parasitic infections to a weak cation exchange chip, and analysed with surface-enhanced laser desorption-ionisation time-of-flight mass spectrometry. Mass spectra were then assessed with three powerful data-mining tools: a tree classifier, a neural network, and a genetic algorithm. Spectra (2-100 kDa) were grouped into training (n=122) and testing (n=109) sets. The training set enabled data-mining software to identify distinct serum proteomic signatures characteristic of human African trypanosomiasis among 206 protein clusters. Sensitivity and specificity, determined with the testing set, were 100% and 98.6%, respectively, when the majority opinion of the three algorithms was considered. This novel approach is much more accurate than any other diagnostic test. Our report of the accurate diagnosis of an infection by use of proteomic signature analysis could form the basis for diagnostic tests for the disease, monitoring of response to treatment, and for improving the accuracy of patient recruitment in large-scale epidemiological studies.

  4. Accurate volume measurement system for plutonium nitrate solution

    Energy Technology Data Exchange (ETDEWEB)

    Hosoma, Takashi; Maruishi, Yoshihiro (Power Reactor and Nuclear Fuel Development Corp., Tokai, Ibaraki (Japan). Tokai Works); Aritomi, Masanori; Kawa, Tunemichi

    1993-05-01

    An accurate volume measurement system for a large amount of plutonium nitrate solution stored in a reprocessing or a conversion plant has been developed at the Plutonium Conversion Development Facility (PCDF) in the Power Reactor and Nuclear Fuel Development Corp. (PNC) Tokai Works. A pair of differential digital quartz pressure transducers is utilized in the volume measurement system. To obtain high accuracy, it is important that the non-linearity of the transducer is minimized within the measurement range, the zero point is stabilized, and the damping property of the pneumatic line is designed to minimize pressure oscillation. The accuracy of the pressure measurement can always be within 2Pa with re-calibration once a year. In the PCDF, the overall uncertainty of the volume measurement has been evaluated to be within 0.2 %. This system has been successfully applied to the Japanese government's and IAEA's routine inspection since 1984. (author).

  5. Calibration Techniques for Accurate Measurements by Underwater Camera Systems.

    Science.gov (United States)

    Shortis, Mark

    2015-12-07

    Calibration of a camera system is essential to ensure that image measurements result in accurate estimates of locations and dimensions within the object space. In the underwater environment, the calibration must implicitly or explicitly model and compensate for the refractive effects of waterproof housings and the water medium. This paper reviews the different approaches to the calibration of underwater camera systems in theoretical and practical terms. The accuracy, reliability, validation and stability of underwater camera system calibration are also discussed. Samples of results from published reports are provided to demonstrate the range of possible accuracies for the measurements produced by underwater camera systems.

  6. Calibration Techniques for Accurate Measurements by Underwater Camera Systems

    Directory of Open Access Journals (Sweden)

    Mark Shortis

    2015-12-01

    Full Text Available Calibration of a camera system is essential to ensure that image measurements result in accurate estimates of locations and dimensions within the object space. In the underwater environment, the calibration must implicitly or explicitly model and compensate for the refractive effects of waterproof housings and the water medium. This paper reviews the different approaches to the calibration of underwater camera systems in theoretical and practical terms. The accuracy, reliability, validation and stability of underwater camera system calibration are also discussed. Samples of results from published reports are provided to demonstrate the range of possible accuracies for the measurements produced by underwater camera systems.

  7. Can Measured Synergy Excitations Accurately Construct Unmeasured Muscle Excitations?

    Science.gov (United States)

    Bianco, Nicholas A; Patten, Carolynn; Fregly, Benjamin J

    2018-01-01

    Accurate prediction of muscle and joint contact forces during human movement could improve treatment planning for disorders such as osteoarthritis, stroke, Parkinson's disease, and cerebral palsy. Recent studies suggest that muscle synergies, a low-dimensional representation of a large set of muscle electromyographic (EMG) signals (henceforth called "muscle excitations"), may reduce the redundancy of muscle excitation solutions predicted by optimization methods. This study explores the feasibility of using muscle synergy information extracted from eight muscle EMG signals (henceforth called "included" muscle excitations) to accurately construct muscle excitations from up to 16 additional EMG signals (henceforth called "excluded" muscle excitations). Using treadmill walking data collected at multiple speeds from two subjects (one healthy, one poststroke), we performed muscle synergy analysis on all possible subsets of eight included muscle excitations and evaluated how well the calculated time-varying synergy excitations could construct the remaining excluded muscle excitations (henceforth called "synergy extrapolation"). We found that some, but not all, eight-muscle subsets yielded synergy excitations that achieved >90% extrapolation variance accounted for (VAF). Using the top 10% of subsets, we developed muscle selection heuristics to identify included muscle combinations whose synergy excitations achieved high extrapolation accuracy. For 3, 4, and 5 synergies, these heuristics yielded extrapolation VAF values approximately 5% lower than corresponding reconstruction VAF values for each associated eight-muscle subset. These results suggest that synergy excitations obtained from experimentally measured muscle excitations can accurately construct unmeasured muscle excitations, which could help limit muscle excitations predicted by muscle force optimizations.

  8. Atomic spectroscopy and highly accurate measurement: determination of fundamental constants

    International Nuclear Information System (INIS)

    Schwob, C.

    2006-12-01

    This document reviews the theoretical and experimental achievements of the author concerning highly accurate atomic spectroscopy applied for the determination of fundamental constants. A pure optical frequency measurement of the 2S-12D 2-photon transitions in atomic hydrogen and deuterium has been performed. The experimental setting-up is described as well as the data analysis. Optimized values for the Rydberg constant and Lamb shifts have been deduced (R = 109737.31568516 (84) cm -1 ). An experiment devoted to the determination of the fine structure constant with an aimed relative uncertainty of 10 -9 began in 1999. This experiment is based on the fact that Bloch oscillations in a frequency chirped optical lattice are a powerful tool to transfer coherently many photon momenta to the atoms. We have used this method to measure accurately the ratio h/m(Rb). The measured value of the fine structure constant is α -1 = 137.03599884 (91) with a relative uncertainty of 6.7*10 -9 . The future and perspectives of this experiment are presented. This document presented before an academic board will allow his author to manage research work and particularly to tutor thesis students. (A.C.)

  9. A spectroscopic transfer standard for accurate atmospheric CO measurements

    Science.gov (United States)

    Nwaboh, Javis A.; Li, Gang; Serdyukov, Anton; Werhahn, Olav; Ebert, Volker

    2016-04-01

    Atmospheric carbon monoxide (CO) is a precursor of essential climate variables and has an indirect effect for enhancing global warming. Accurate and reliable measurements of atmospheric CO concentration are becoming indispensable. WMO-GAW reports states a compatibility goal of ±2 ppb for atmospheric CO concentration measurements. Therefore, the EMRP-HIGHGAS (European metrology research program - high-impact greenhouse gases) project aims at developing spectroscopic transfer standards for CO concentration measurements to meet this goal. A spectroscopic transfer standard would provide results that are directly traceable to the SI, can be very useful for calibration of devices operating in the field, and could complement classical gas standards in the field where calibration gas mixtures in bottles often are not accurate, available or stable enough [1][2]. Here, we present our new direct tunable diode laser absorption spectroscopy (dTDLAS) sensor capable of performing absolute ("calibration free") CO concentration measurements, and being operated as a spectroscopic transfer standard. To achieve the compatibility goal stated by WMO for CO concentration measurements and ensure the traceability of the final concentration results, traceable spectral line data especially line intensities with appropriate uncertainties are needed. Therefore, we utilize our new high-resolution Fourier-transform infrared (FTIR) spectroscopy CO line data for the 2-0 band, with significantly reduced uncertainties, for the dTDLAS data evaluation. Further, we demonstrate the capability of our sensor for atmospheric CO measurements, discuss uncertainty calculation following the guide to the expression of uncertainty in measurement (GUM) principles and show that CO concentrations derived using the sensor, based on the TILSAM (traceable infrared laser spectroscopic amount fraction measurement) method, are in excellent agreement with gravimetric values. Acknowledgement Parts of this work have been

  10. Measurement and Accurate Interpretation of the Solubility of Pharmaceutical Salts.

    Science.gov (United States)

    He, Yan; Ho, Chris; Yang, Donglai; Chen, Jeane; Orton, Edward

    2017-05-01

    Salt formation is one of the primary approaches to improve the developability of ionizable poorly water-soluble compounds. Solubility determination of the salt candidates in aqueous media or biorelevant fluids is a critical step in salt screening. Salt solubility measurements can be complicated due to dynamic changes in both solution and solid phases. Because of the early implementation of salt screening in research, solubility measurements often are performed using minimal amount of material. Some salts have transient high solubility on dissolution. Recognition of these transients can be critical in developing these salts into drug products. This minireview focuses on challenges in salt solubility measurements due to the changes in solution caused by self-buffering effects of dissolved species and the changes in solid phase due to solid-state phase transformations. Solubility measurements and their accurate interpretation are assessed in the context of dissolution monitoring and solid-phase analysis technologies. A harmonized method for reporting salt solubility measurements is recommended to reduce errors and to align with the U.S. Pharmacopeial policy and Food and Drug Administration recommendations for drug products containing pharmaceutical salts. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  11. Accurate fluid force measurement based on control surface integration

    Science.gov (United States)

    Lentink, David

    2018-01-01

    Nonintrusive 3D fluid force measurements are still challenging to conduct accurately for freely moving animals, vehicles, and deforming objects. Two techniques, 3D particle image velocimetry (PIV) and a new technique, the aerodynamic force platform (AFP), address this. Both rely on the control volume integral for momentum; whereas PIV requires numerical integration of flow fields, the AFP performs the integration mechanically based on rigid walls that form the control surface. The accuracy of both PIV and AFP measurements based on the control surface integration is thought to hinge on determining the unsteady body force associated with the acceleration of the volume of displaced fluid. Here, I introduce a set of non-dimensional error ratios to show which fluid and body parameters make the error negligible. The unsteady body force is insignificant in all conditions where the average density of the body is much greater than the density of the fluid, e.g., in gas. Whenever a strongly deforming body experiences significant buoyancy and acceleration, the error is significant. Remarkably, this error can be entirely corrected for with an exact factor provided that the body has a sufficiently homogenous density or acceleration distribution, which is common in liquids. The correction factor for omitting the unsteady body force, {{{ {ρ f}} {1 - {ρ f} ( {{ρ b}+{ρ f}} )}.{( {{{{ρ }}b}+{ρ f}} )}}} , depends only on the fluid, {ρ f}, and body, {{ρ }}b, density. Whereas these straightforward solutions work even at the liquid-gas interface in a significant number of cases, they do not work for generalized bodies undergoing buoyancy in combination with appreciable body density inhomogeneity, volume change (PIV), or volume rate-of-change (PIV and AFP). In these less common cases, the 3D body shape needs to be measured and resolved in time and space to estimate the unsteady body force. The analysis shows that accounting for the unsteady body force is straightforward to non

  12. Accurate measurement of RF exposure from emerging wireless communication systems

    International Nuclear Information System (INIS)

    Letertre, Thierry; Toffano, Zeno; Monebhurrun, Vikass

    2013-01-01

    Isotropic broadband probes or spectrum analyzers (SAs) may be used for the measurement of rapidly varying electromagnetic fields generated by emerging wireless communication systems. In this paper this problematic is investigated by comparing the responses measured by two different isotropic broadband probes typically used to perform electric field (E-field) evaluations. The broadband probes are submitted to signals with variable duty cycles (DC) and crest factors (CF) either with or without Orthogonal Frequency Division Multiplexing (OFDM) modulation but with the same root-mean-square (RMS) power. The two probes do not provide accurate enough results for deterministic signals such as Worldwide Interoperability for Microwave Access (WIMAX) or Long Term Evolution (LTE) as well as for non-deterministic signals such as Wireless Fidelity (WiFi). The legacy measurement protocols should be adapted to cope for the emerging wireless communication technologies based on the OFDM modulation scheme. This is not easily achieved except when the statistics of the RF emission are well known. In this case the measurement errors are shown to be systematic and a correction factor or calibration can be applied to obtain a good approximation of the total RMS power.

  13. Study of accurate volume measurement system for plutonium nitrate solution

    Energy Technology Data Exchange (ETDEWEB)

    Hosoma, T. [Power Reactor and Nuclear Fuel Development Corp., Tokai, Ibaraki (Japan). Tokai Works

    1998-12-01

    It is important for effective safeguarding of nuclear materials to establish a technique for accurate volume measurement of plutonium nitrate solution in accountancy tank. The volume of the solution can be estimated by two differential pressures between three dip-tubes, in which the air is purged by an compressor. One of the differential pressure corresponds to the density of the solution, and another corresponds to the surface level of the solution in the tank. The measurement of the differential pressure contains many uncertain errors, such as precision of pressure transducer, fluctuation of back-pressure, generation of bubbles at the front of the dip-tubes, non-uniformity of temperature and density of the solution, pressure drop in the dip-tube, and so on. The various excess pressures at the volume measurement are discussed and corrected by a reasonable method. High precision-differential pressure measurement system is developed with a quartz oscillation type transducer which converts a differential pressure to a digital signal. The developed system is used for inspection by the government and IAEA. (M. Suetake)

  14. Precise and accurate isotope ratio measurements by ICP-MS.

    Science.gov (United States)

    Becker, J S; Dietze, H J

    2000-09-01

    The precise and accurate determination of isotope ratios by inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS (LA-ICP-MS) is important for quite different application fields (e.g. for isotope ratio measurements of stable isotopes in nature, especially for the investigation of isotope variation in nature or age dating, for determining isotope ratios of radiogenic elements in the nuclear industry, quality assurance of fuel material, for reprocessing plants, nuclear material accounting and radioactive waste control, for tracer experiments using stable isotopes or long-lived radionuclides in biological or medical studies). Thermal ionization mass spectrometry (TIMS), which used to be the dominant analytical technique for precise isotope ratio measurements, is being increasingly replaced for isotope ratio measurements by ICP-MS due to its excellent sensitivity, precision and good accuracy. Instrumental progress in ICP-MS was achieved by the introduction of the collision cell interface in order to dissociate many disturbing argon-based molecular ions, thermalize the ions and neutralize the disturbing argon ions of plasma gas (Ar+). The application of the collision cell in ICP-QMS results in a higher ion transmission, improved sensitivity and better precision of isotope ratio measurements compared to quadrupole ICP-MS without the collision cell [e.g., for 235U/238U approximately 1 (10 microg x L(-1) uranium) 0.07% relative standard deviation (RSD) vs. 0.2% RSD in short-term measurements (n = 5)]. A significant instrumental improvement for ICP-MS is the multicollector device (MC-ICP-MS) in order to obtain a better precision of isotope ratio measurements (with a precision of up to 0.002%, RSD). CE- and HPLC-ICP-MS are used for the separation of isobaric interferences of long-lived radionuclides and stable isotopes by determination of spallation nuclide abundances in an irradiated tantalum target.

  15. Radio Astronomers Set New Standard for Accurate Cosmic Distance Measurement

    Science.gov (United States)

    1999-06-01

    A team of radio astronomers has used the National Science Foundation's Very Long Baseline Array (VLBA) to make the most accurate measurement ever made of the distance to a faraway galaxy. Their direct measurement calls into question the precision of distance determinations made by other techniques, including those announced last week by a team using the Hubble Space Telescope. The radio astronomers measured a distance of 23.5 million light-years to a galaxy called NGC 4258 in Ursa Major. "Ours is a direct measurement, using geometry, and is independent of all other methods of determining cosmic distances," said Jim Herrnstein, of the National Radio Astronomy Observatory (NRAO) in Socorro, NM. The team says their measurement is accurate to within less than a million light-years, or four percent. The galaxy is also known as Messier 106 and is visible with amateur telescopes. Herrnstein, along with James Moran and Lincoln Greenhill of the Harvard- Smithsonian Center for Astrophysics; Phillip Diamond, of the Merlin radio telescope facility at Jodrell Bank and the University of Manchester in England; Makato Inoue and Naomasa Nakai of Japan's Nobeyama Radio Observatory; Mikato Miyoshi of Japan's National Astronomical Observatory; Christian Henkel of Germany's Max Planck Institute for Radio Astronomy; and Adam Riess of the University of California at Berkeley, announced their findings at the American Astronomical Society's meeting in Chicago. "This is an incredible achievement to measure the distance to another galaxy with this precision," said Miller Goss, NRAO's Director of VLA/VLBA Operations. "This is the first time such a great distance has been measured this accurately. It took painstaking work on the part of the observing team, and it took a radio telescope the size of the Earth -- the VLBA -- to make it possible," Goss said. "Astronomers have sought to determine the Hubble Constant, the rate of expansion of the universe, for decades. This will in turn lead to an

  16. UAV multirotor platform for accurate turbulence measurements in the atmosphere

    Science.gov (United States)

    Carbajo Fuertes, Fernando; Wilhelm, Lionel; Sin, Kevin Edgar; Hofer, Matthias; Porté-Agel, Fernando

    2017-04-01

    One of the most challenging tasks in atmospheric field studies for wind energy is to obtain accurate turbulence measurements at any location inside the region of interest for a wind farm study. This volume would ideally include from several hundred meters to several kilometers around it and from ground height to the top of the boundary layer. An array of meteorological masts equipped with several sonic anemometers to cover all points of interest would be the best in terms of accuracy and data availability, but it is an obviously unfeasible solution. On the other hand, the evolution of wind LiDAR technology allows to measure at any point in space but unfortunately it involves two important limitations: the first one is the relatively low spatial and temporal resolution when compared to a sonic anemometer and the second one is the fact that the measurements are limited to the velocity component parallel to the laser beam (radial velocity). To overcome the aforementioned drawbacks, a UAV multirotor platform has been developed. It is based on a state-of-the-art octocopter with enough payload to carry laboratory-grade instruments for the measurement of time-resolved atmospheric pressure, three-component velocity vector and temperature; and enough autonomy to fly from 10 to 20 minutes, which is a standard averaging time in most atmospheric measurement applications. The UAV uses a gyroscope, an accelerometer, a GPS and an algorithm has been developed and integrated for the correction of any orientation and movement. This UAV platform opens many possibilities for the study of features that have been almost exclusively studied until now in wind tunnel such as wind turbine blade tip vortex characteristics, near-wake to far-wake transition, momentum entrainment from the higher part of the boundary layer in wind farms, etc. The validation of this new measurement technique has been performed against sonic anemometry in terms of wind speed and temperature time series as well as

  17. Air toxics being measured more accurately, controlled more effectively

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    In response to the directives of the Clean Air Act Amendments, Argonne National Laboratory is developing new or improved pollutant control technologies for industries that burn fossil fuels. This research continues Argonne`s traditional support for the US DOE Flue Gas Cleanup Program. Research is underway to measure process emissions and identify new and improved control measures. Argonne`s emission control research has ranged from experiments in the basic chemistry of pollution-control systems, through laboratory-scale process development and testing to pilot-scale field tests of several technologies. Whenever appropriate, the work has emphasized integrated or combined control systems as the best approach to technologies that offer low cost and good operating characteristics.

  18. Accurate absolute measurement of trapped Cs atoms in a MOT

    International Nuclear Information System (INIS)

    Talavera O, M.; Lopez R, M.; Carlos L, E. de; Jimenez S, S.

    2007-01-01

    A Cs-133 Magneto-Optical Trap (MOT) has been developed at the Time and Frequency Division of the Centro Nacional de Metrologia, CENAM, in Mexico. This MOT is part of a primary frequency standard based on ultra-cold Cs atoms, called CsF-1 clock, under development at CENAM. In this Cs MOT, we use the standard configuration (σ + - σ - ) 4-horizontal 2-vertical laser beams 1.9 cm in diameter, with 5 mW each. We use a 852 nm, 5 mW, DBR laser as a master laser which is stabilized by saturation spectroscopy. Emission linewidth of the master laser is l MHz. In order to amplify the light of the master laser, a 50 mW, 852 nm AlGaAs laser is used as slave laser. This slave laser is stabilized by light injection technique. A 12 MHz red shift of the light is performed by two double passes through two Acusto-Optic Modulators (AOMs). The optical part of the CENAMs MOT is very robust against mechanical vibration, acoustic noise and temperature changes in our laboratory, because none of our diode lasers use an extended cavity to reduce the linewidth. In this paper, we report results of our MOT characterization as a function of several operation parameters such as the intensity of laser beams, the laser beam diameter, the red shift of light, and the gradient of the magnetic field. We also report accurate absolute measurement of the number of Cs atoms trapped in our Cs MOT. We found up to 6 x 10 7 Cs atoms trapped in our MOT measured with an uncertainty no greater than 6.4%. (Author)

  19. Spherical near-field antenna measurements — The most accurate antenna measurement technique

    DEFF Research Database (Denmark)

    Breinbjerg, Olav

    2016-01-01

    The spherical near-field antenna measurement technique combines several advantages and generally constitutes the most accurate technique for experimental characterization of radiation from antennas. This paper/presentation discusses these advantages, briefly reviews the early history and present...

  20. Third trimester ultrasound soft-tissue measurements accurately predicts macrosomia.

    Science.gov (United States)

    Maruotti, Giuseppe Maria; Saccone, Gabriele; Martinelli, Pasquale

    2017-04-01

    To evaluate the accuracy of sonographic measurements of fetal soft tissue in the prediction of macrosomia. Electronic databases were searched from their inception until September 2015 with no limit for language. We included only studies assessing the accuracy of sonographic measurements of fetal soft tissue in the abdomen or thigh in the prediction of macrosomia  ≥34 weeks of gestation. The primary outcome was the accuracy of sonographic measurements of fetal soft tissue in the prediction of macrosomia. We generated the forest plot for the pooled sensitivity and specificity with 95% confidence interval (CI). Additionally, summary receiver-operating characteristics (ROC) curves were plotted and the area under the curve (AUC) was also computed to evaluate the overall performance of the diagnostic test accuracy. Three studies, including 287 singleton gestations, were analyzed. The pooled sensitivity of sonographic measurements of abdominal or thigh fetal soft tissue in the prediction of macrosomia was 80% (95% CI: 66-89%) and the pooled specificity was 95% (95% CI: 91-97%). The AUC for diagnostic accuracy of sonographic measurements of fetal soft tissue in the prediction of macrosomia was 0.92 and suggested high diagnostic accuracy. Third-trimester sonographic measurements of fetal soft tissue after 34 weeks may help to detect macrosomia with a high degree of accuracy. The pooled detection rate was 80%. A standardization of measurements criteria, reproducibility, building reference charts of fetal subcutaneous tissue and large studies to assess the optimal cutoff of fetal adipose thickness are necessary before the introduction of fetal soft-tissue markers in the clinical practice.

  1. Testing the Limits to Accurate Comminution Dates: A Progress Report

    Science.gov (United States)

    Piccione, G.; Blackburn, T.; Edwards, G. H.

    2017-12-01

    The ability to resolve the timing of fine particle production holds potential for contributing to several Earth Science sub-disciplines including glaciology, eolian and fluvial geomorphology, soil production, and fault dynamics. A relatively new geochronologic tool, U-series comminution dating, has shown potential to directly date the timing of particle comminution. This system's sensitivity to particle size arises from a physical disequilibrium in the 238U decay chain generated by the ejected loss of intermediate daughter products (e.g. 234U). It is the goal of this ongoing study to develop and test analytical procedures to improve the accuracy of comminution dating. In the geologic settings explored by previous studies, comminution dates integrate both the time of particle transport and time since deposition. To better test the accuracy of comminution dates, our study focuses on settings where silt has experienced little to no transport time, specifically, glacial moraines in the Eastern Sierras and Rock Avalanches in the San Gabriel Mountains, both locations with existing independent geochronologic constraints. Previous studies demonstrate the dependency of U-series comminution date on grain size and shape. Here we show that mineralogy of samples also plays a role, possibly controlled by the uranium content and crystal bond strength. To separate samples by size and mineralogy, we use dry sonic-sieving, density and magnetic separation. Non-detrital materials deposited on the rim of comminuted grains have an isotopic composition that is unrelated to the isotopic evolution since comminution and therefore must be removed through a multi-step leaching procedure. Leaching is complicated by the fact that areas within the comminuted crystal that have experienced physical fractionation are contained within damaged zones and are prone to being leached themselves, which removes areas of interest from the crystal. We present progress made on a sample processing method

  2. Accurate position estimation methods based on electrical impedance tomography measurements

    Science.gov (United States)

    Vergara, Samuel; Sbarbaro, Daniel; Johansen, T. A.

    2017-08-01

    than 0.05% of the tomograph radius value. These results demonstrate that the proposed approaches can estimate an object’s position accurately based on EIT measurements if enough process information is available for training or modelling. Since they do not require complex calculations it is possible to use them in real-time applications without requiring high-performance computers.

  3. Accurate position estimation methods based on electrical impedance tomography measurements

    International Nuclear Information System (INIS)

    Vergara, Samuel; Sbarbaro, Daniel; Johansen, T A

    2017-01-01

    than 0.05% of the tomograph radius value. These results demonstrate that the proposed approaches can estimate an object’s position accurately based on EIT measurements if enough process information is available for training or modelling. Since they do not require complex calculations it is possible to use them in real-time applications without requiring high-performance computers. (paper)

  4. Distributed Unit Testing: supporting multiple platforms accurately and efficiently

    OpenAIRE

    García-Peñalvo, Francisco José; Santos, Pablo

    2006-01-01

    Testing is the most basic way to check the evolution of a software project. A strong test suite helps development team assuring that a certain minimum is always kept. Release after release software must pass a test group, large enough to check, at least, the most common use cases. Results will numerically show project s progress. Depending on the project testing could be done on different platforms under various operating systems. Forcing race conditions and heavy load is also a desired featu...

  5. Weak Weak Lensing : How Accurately Can Small Shears be Measured?

    NARCIS (Netherlands)

    Kuijken, K.

    2006-01-01

    Abstract: Now that weak lensing signals on the order of a percent are actively being searched for (cosmic shear, galaxy-galaxy lensing, large radii in clusters...) it is important to investigate how accurately weak shears can be determined. Many systematic effects are present, and need to be

  6. Accurate anisotropic material modelling using only tensile tests for hot and cold forming

    Science.gov (United States)

    Abspoel, M.; Scholting, M. E.; Lansbergen, M.; Neelis, B. M.

    2017-09-01

    Accurate material data for simulations require a lot of effort. Advanced yield loci require many different kinds of tests and a Forming Limit Curve (FLC) needs a large amount of samples. Many people use simple material models to reduce the effort of testing, however some models are either not accurate enough (i.e. Hill’48), or do not describe new types of materials (i.e. Keeler). Advanced yield loci describe the anisotropic materials behaviour accurately, but are not widely adopted because of the specialized tests, and data post-processing is a hurdle for many. To overcome these issues, correlations between the advanced yield locus points (biaxial, plane strain and shear) and mechanical properties have been investigated. This resulted in accurate prediction of the advanced stress points using only Rm, Ag and r-values in three directions from which a Vegter yield locus can be constructed with low effort. FLC’s can be predicted with the equations of Abspoel & Scholting depending on total elongation A80, r-value and thickness. Both predictive methods are initially developed for steel, aluminium and stainless steel (BCC and FCC materials). The validity of the predicted Vegter yield locus is investigated with simulation and measurements on both hot and cold formed parts and compared with Hill’48. An adapted specimen geometry, to ensure a homogeneous temperature distribution in the Gleeble hot tensile test, was used to measure the mechanical properties needed to predict a hot Vegter yield locus. Since for hot material, testing of stress states other than uniaxial is really challenging, the prediction for the yield locus adds a lot of value. For the hot FLC an A80 sample with a homogeneous temperature distribution is needed which is due to size limitations not possible in the Gleeble tensile tester. Heating the sample in an industrial type furnace and tensile testing it in a dedicated device is a good alternative to determine the necessary parameters for the FLC

  7. Handcrafted cuff manometers do not accurately measure endotracheal tube cuff pressure.

    Science.gov (United States)

    Annoni, Raquel; de Almeida Junior, Antonio Evanir

    2015-01-01

    To test the agreement between two handcrafted devices and a cuff-specific manometer. The agreement between two handcrafted devices adapted to measure tracheal tube cuff pressure and a cuff-specific manometer was tested on 79 subjects. The cuff pressure was measured with a commercial manometer and with two handcrafted devices (HD) assembled with aneroid sphygmomanometers (HD1 and HD2). The data were compared using Wilcoxon and Spearman tests, the intraclass correlation coefficient (ICC) and limit-of-agreement analysis. Cuff pressures assessed with handcrafted devices were significantly different from commercial device measurements (pressures were higher when measured with HD1 and lower with HD2). The ICCs between the commercial device and HD1 and HD2 were excellent (ICC = 0.8 p manometers do not provide accurate cuff pressure measurements when compared to a cuff-specific device and should not be used to replace the commercial cuff manometers in mechanically ventilated patients.

  8. Accurate dating with radiocarbon from the atom bomb tests

    CSIR Research Space (South Africa)

    Vogel, JC

    2002-09-01

    Full Text Available The artificial radiocarbon produced by the thermonuclear bomb tests in the 1950s and 1960s significantly increased the level of C-14 in the environment. A detailed record of the subsequent changes in the C-14 concentration of the atmosphere can...

  9. Thermal Testing Measurements Report

    Energy Technology Data Exchange (ETDEWEB)

    R. Wagner

    2002-09-26

    The purpose of the Thermal Testing Measurements Report (Scientific Analysis Report) is to document, in one report, the comprehensive set of measurements taken within the Yucca Mountain Project Thermal Testing Program since its inception in 1996. Currently, the testing performed and measurements collected are either scattered in many level 3 and level 4 milestone reports or, in the case of the ongoing Drift Scale Test, mostly documented in eight informal progress reports. Documentation in existing reports is uneven in level of detail and quality. Furthermore, while all the data collected within the Yucca Mountain Site Characterization Project (YMP) Thermal Testing Program have been submitted periodically to the Technical Data Management System (TDMS), the data structure--several incremental submittals, and documentation formats--are such that the data are often not user-friendly except to those who acquired and processed the data. The documentation in this report is intended to make data collected within the YMP Thermal Testing Program readily usable to end users, such as those representing the Performance Assessment Project, Repository Design Project, and Engineered Systems Sub-Project. Since either detailed level 3 and level 4 reports exist or the measurements are straightforward, only brief discussions are provided for each data set. These brief discussions for different data sets are intended to impart a clear sense of applicability of data, so that they will be used properly within the context of measurement uncertainty. This approach also keeps this report to a manageable size, an important consideration because the report encompasses nearly all measurements for three long-term thermal tests. As appropriate, thermal testing data currently residing in the TDMS have been reorganized and reformatted from cumbersome, user-unfriendly Input-Data Tracking Numbers (DTNs) into a new set of Output-DTNs. These Output-DTNs provide a readily usable data structure

  10. ORIGINAL ARTICLE ORIG Is airway diameter measured accurately ...

    African Journals Online (AJOL)

    SA JOURNAL OF RADIOLOGY • September 2010 selected children of this study was 4.2 mm (measured in soft tissue windows). Graph 1 illustrates little difference (ICC agreement 0.950) between the sets of measurements of stenosis in the trachea, with a high consistency value (ICC consistency 0.946). Of the differences in.

  11. Accurate Measurements of Spectral Reflectance in Picasso's Guernica Painting.

    Science.gov (United States)

    de Luna, Javier Muñoz; Fernandez-Balbuena, Antonio Alvarez; Vázquez, Daniel; Melgosa, Manuel; Durán, Humberto; García, Jorge; Muro, Carmen

    2016-01-01

    The use of non-invasive spectral measurements to control the conservation status is a part of the preventive conservation of artworks which nowadays is becoming increasingly interesting. This paper describes how to use a spectral measuring device and an illumination system specifically designed for such a task in a very large dimension artwork painting (7.8 m wide × 3.5 m high). The system, controlled by a Cartesian robot, allows spectral measurements in a spectral range of 400-780 nm. The measured data array has a total of 2201 circular regions with 5.5 mm spot diameter placed on a square grid. Colorimetric calculations performed from these spectral measurements may be used to characterize color shifts related to reflectance changes in specific areas of the paint. A color shifting from the expected gray has been shown. © The Author(s) 2015.

  12. An accurate method for measuring triploidy of larval fish spawns

    Science.gov (United States)

    Jenkins, Jill A.; Draugelis-Dale, Rassa O.; Glennon, Robert; Kelly, Anita; Brown, Bonnie L.; Morrison, John

    2017-01-01

    A standard flow cytometric protocol was developed for estimating triploid induction in batches of larval fish. Polyploid induction treatments are not guaranteed to be 100% efficient, thus the ability to quantify the proportion of triploid larvae generated by a particular treatment helps managers to stock high-percentage spawns and researchers to select treatments for efficient triploid induction. At 3 d posthatch, individual Grass Carp Ctenopharyngodon idella were mechanically dissociated into single-cell suspensions; nuclear DNA was stained with propidium iodide then analyzed by flow cytometry. Following ploidy identification of individuals, aliquots of diploid and triploid cell suspensions were mixed to generate 15 levels (0–100%) of known triploidy (n = 10). Using either 20 or 50 larvae per level, the observed triploid percentages were lower than the known, actual values. Using nonlinear regression analyses, quadratic equations solved for triploid proportions in mixed samples and corresponding estimation reference plots allowed for predicting triploidy. Thus, an accurate prediction of the proportion of triploids in a spawn can be made by following a standard larval processing and analysis protocol with either 20 or 50 larvae from a single spawn, coupled with applying the quadratic equations or reference plots to observed flow cytometry results. Due to the universality of triploid DNA content being 1.5 times the diploid level and because triploid fish consist of fewer cells than diploids, this method should be applicable to other produced triploid fish species, and it may be adapted for use with bivalves or other species where batch analysis is appropriate.

  13. Rapid and accurate control rod calibration measurement and analysis

    International Nuclear Information System (INIS)

    Nelson, George W.; Doane, Harry J.

    1990-01-01

    In order to reduce the time needed to perform control rod calibrations and improve the accuracy of the results, a technique for a measurement, analysis, and tabulation of integral rod worths has been developed. A single series of critical rod positions are determined at constant low power to reduce the waiting time between positive period measurements and still assure true stable reactor period data. Reactivity values from positive period measurements and control rod drop measurements are used as input data for a non-linear fit to the expected control rod integral worth shape. With this method, two control rods can be calibrated in about two hours, and integral and differential calibration tables for operator use are printed almost immediately. Listings of the BASIC computer programs for the non-linear fitting and calibration table preparation are provided. (author)

  14. Accurate Blood Flow Measurements : Are Artificial Tracers Necessary?

    NARCIS (Netherlands)

    Poelma, C.; Kloosterman, A.; Hierck, B.P.; Westerweel, J.

    2012-01-01

    Imaging-based blood flow measurement techniques, such as particle image velocimetry, have become an important tool in cardiovascular research. They provide quantitative information about blood flow, which benefits applications ranging from developmental biology to tumor perfusion studies. Studies

  15. Accurate image search using the contextual dissimilarity measure

    OpenAIRE

    Jégou , Hervé; Schmid , Cordelia; Harzallah , Hedi; Verbeek , Jakob

    2010-01-01

    International audience; This paper introduces the contextual dissimilarity measure which significantly improves the accuracy of bag-of-features based image search. Our measure takes into account the local distribution of the vectors and iteratively estimates distance update terms in the spirit of Sinkhorn's scaling algorithm, thereby modifying the neighborhood structure. Experimental results show that our approach gives significantly better results than a standard distance and outperforms the...

  16. An accurate automated technique for quasi-optics measurement of the microwave diagnostics for fusion plasma

    Science.gov (United States)

    Hu, Jianqiang; Liu, Ahdi; Zhou, Chu; Zhang, Xiaohui; Wang, Mingyuan; Zhang, Jin; Feng, Xi; Li, Hong; Xie, Jinlin; Liu, Wandong; Yu, Changxuan

    2017-08-01

    A new integrated technique for fast and accurate measurement of the quasi-optics, especially for the microwave/millimeter wave diagnostic systems of fusion plasma, has been developed. Using the LabVIEW-based comprehensive scanning system, we can realize not only automatic but also fast and accurate measurement, which will help to eliminate the effects of temperature drift and standing wave/multi-reflection. With the Matlab-based asymmetric two-dimensional Gaussian fitting method, all the desired parameters of the microwave beam can be obtained. This technique can be used in the design and testing of microwave diagnostic systems such as reflectometers and the electron cyclotron emission imaging diagnostic systems of the Experimental Advanced Superconducting Tokamak.

  17. A simple and accurate relative alternative magnetic susceptibility measurement technique

    Energy Technology Data Exchange (ETDEWEB)

    Zawilski, B.M., E-mail: zawilski@grenoble.cnrs.f [Institut Neel-MCMF--CNRS-UJF 25, Rue des Martyrs, F 38042 Grenoble Cedex (France); Marcus, J.; Plaindoux, P. [Institut Neel-MCMF-CNRS-UJF 25, Rue des Martyrs, F 38042 Grenoble Cedex (France)

    2010-09-15

    Investigation of relative AC magnetic susceptibility interests for many magnetic transition studies such as superconductor transition. A technique based on mutual or self inductive measure provides a fast and relatively easy (no contact) way to determinate the temperature of any transition affecting the magnetic susceptibility. The half Wheatstone inductive/resistive bridge is used instead of the usual RLC quarter bridge in order to balance the bore inductance of the coil. A comparison between quarter and half bridge measurements illustrates the accuracy of our device.

  18. Accurate image search using the contextual dissimilarity measure.

    Science.gov (United States)

    Jegou, Hervé; Schmid, Cordelia; Harzallah, Hedi; Verbeek, Jakob

    2010-01-01

    This paper introduces the contextual dissimilarity measure, which significantly improves the accuracy of bag-of-features-based image search. Our measure takes into account the local distribution of the vectors and iteratively estimates distance update terms in the spirit of Sinkhorn's scaling algorithm, thereby modifying the neighborhood structure. Experimental results show that our approach gives significantly better results than a standard distance and outperforms the state of the art in terms of accuracy on the Nistér-Stewénius and Lola data sets. This paper also evaluates the impact of a large number of parameters, including the number of descriptors, the clustering method, the visual vocabulary size, and the distance measure. The optimal parameter choice is shown to be quite context-dependent. In particular, using a large number of descriptors is interesting only when using our dissimilarity measure. We have also evaluated two novel variants: multiple assignment and rank aggregation. They are shown to further improve accuracy at the cost of higher memory usage and lower efficiency.

  19. Accurate antenna reflector loss measurements for radiometer calibration budget

    DEFF Research Database (Denmark)

    Skou, Niels

    1996-01-01

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

  20. Highly accurate photogrammetric measurements of the Planck reflectors

    Science.gov (United States)

    Amiri Parian, Jafar; Gruen, Armin; Cozzani, Alessandro

    2017-11-01

    The Planck mission of the European Space Agency (ESA) is designed to image the anisotropies of the Cosmic Background Radiation Field over the whole sky. To achieve this aim, sophisticated reflectors are used as part of the Planck telescope receiving system. The system consists of secondary and primary reflectors which are sections of two different ellipsoids of revolution with mean diameters of 1 and 1.6 meters. Deformations of the reflectors which influence the optical parameters and the gain of receiving signals are investigated in vacuum and at very low temperatures. For this investigation, among the various high accuracy measurement techniques, photogrammetry was selected. With respect to the photogrammetric measurements, special considerations had to be taken into account in design steps, measurement arrangement and data processing to achieve very high accuracies. The determinability of additional parameters of the camera under the given network configuration, datum definition, reliability and precision issues as well as workspace limits and propagating errors from different sources are considered. We have designed an optimal photogrammetric network by heuristic simulation for the flight model of the primary and the secondary reflectors with relative precisions better than 1:1000'000 and 1:400'000 to achieve the requested accuracies. A least squares best fit ellipsoid method was developed to determine the optical parameters of the reflectors. In this paper we will report about the procedures, the network design and the results of real measurements.

  1. Highly accurate adaptive TOF determination method for ultrasonic thickness measurement

    Science.gov (United States)

    Zhou, Lianjie; Liu, Haibo; Lian, Meng; Ying, Yangwei; Li, Te; Wang, Yongqing

    2018-04-01

    Determining the time of flight (TOF) is very critical for precise ultrasonic thickness measurement. However, the relatively low signal-to-noise ratio (SNR) of the received signals would induce significant TOF determination errors. In this paper, an adaptive time delay estimation method has been developed to improve the TOF determination’s accuracy. An improved variable step size adaptive algorithm with comprehensive step size control function is proposed. Meanwhile, a cubic spline fitting approach is also employed to alleviate the restriction of finite sampling interval. Simulation experiments under different SNR conditions were conducted for performance analysis. Simulation results manifested the performance advantage of proposed TOF determination method over existing TOF determination methods. When comparing with the conventional fixed step size, and Kwong and Aboulnasr algorithms, the steady state mean square deviation of the proposed algorithm was generally lower, which makes the proposed algorithm more suitable for TOF determination. Further, ultrasonic thickness measurement experiments were performed on aluminum alloy plates with various thicknesses. They indicated that the proposed TOF determination method was more robust even under low SNR conditions, and the ultrasonic thickness measurement accuracy could be significantly improved.

  2. System to measure accurate temperature dependence of electric conductivity down to 20 K in ultrahigh vacuum.

    Science.gov (United States)

    Sakai, C; Takeda, S N; Daimon, H

    2013-07-01

    We have developed the new in situ electrical-conductivity measurement system which can be operated in ultrahigh vacuum (UHV) with accurate temperature measurement down to 20 K. This system is mainly composed of a new sample-holder fixing mechanism, a new movable conductivity-measurement mechanism, a cryostat, and two receptors for sample- and four-probe holders. Sample-holder is pushed strongly against the receptor, which is connected to a cryostat, by using this new sample-holder fixing mechanism to obtain high thermal conductivity. Test pieces on the sample-holders have been cooled down to about 20 K using this fixing mechanism, although they were cooled down to only about 60 K without this mechanism. Four probes are able to be touched to a sample surface using this new movable conductivity-measurement mechanism for measuring electrical conductivity after making film on substrates or obtaining clean surfaces by cleavage, flashing, and so on. Accurate temperature measurement is possible since the sample can be transferred with a thermocouple and∕or diode being attached directly to the sample. A single crystal of Bi-based copper oxide high-Tc superconductor (HTSC) was cleaved in UHV to obtain clean surface, and its superconducting critical temperature has been successfully measured in situ. The importance of in situ measurement of resistance in UHV was demonstrated for this HTSC before and after cesium (Cs) adsorption on its surface. The Tc onset increase and the Tc offset decrease by Cs adsorption were observed.

  3. Diamond micro-Raman thermometers for accurate gate temperature measurements

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Roland B.; Pomeroy, James W.; Kuball, Martin [Center for Device Thermography and Reliability, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom)

    2014-05-26

    Determining the peak channel temperature in AlGaN/GaN high electron mobility transistors and other devices with high accuracy is an important and challenging issue. A surface-sensitive thermometric technique is demonstrated, utilizing Raman thermography and diamond microparticles to measure the gate temperature. This technique enhances peak channel temperature estimation, especially when it is applied in combination with standard micro-Raman thermography. Its application to other metal-covered areas of devices, such as field plates is demonstrated. Furthermore, this technique can be readily applied to other material/device systems.

  4. Diamond micro-Raman thermometers for accurate gate temperature measurements

    International Nuclear Information System (INIS)

    Simon, Roland B.; Pomeroy, James W.; Kuball, Martin

    2014-01-01

    Determining the peak channel temperature in AlGaN/GaN high electron mobility transistors and other devices with high accuracy is an important and challenging issue. A surface-sensitive thermometric technique is demonstrated, utilizing Raman thermography and diamond microparticles to measure the gate temperature. This technique enhances peak channel temperature estimation, especially when it is applied in combination with standard micro-Raman thermography. Its application to other metal-covered areas of devices, such as field plates is demonstrated. Furthermore, this technique can be readily applied to other material/device systems.

  5. Accurate assessment of exposure using tracer gas measurements

    DEFF Research Database (Denmark)

    Kierat, Wojciech; Bivolarova, Mariya; Zavrl, Eva

    2018-01-01

    Room airflow interaction, particularly in the breathing zone, is important to assess exposure to indoor air pollution. A breathing thermal manikin was used to simulate a room occupant with the convective boundary layer (CBL) generated around the body and the respiratory flow. Local airflow against...... the face of the manikin was applied to increase the complexity of the airflow interaction. CO2 was released at the armpits and N2O at the groin to simulate the respective bio-effluents generated at these two body sites. The tracer gas concentration at the mouth/nose of the manikin was measured with gas...

  6. Accurate Blood Flow Measurements: Are Artificial Tracers Necessary?

    Science.gov (United States)

    Poelma, Christian; Kloosterman, Astrid; Hierck, Beerend P.; Westerweel, Jerry

    2012-01-01

    Imaging-based blood flow measurement techniques, such as particle image velocimetry, have become an important tool in cardiovascular research. They provide quantitative information about blood flow, which benefits applications ranging from developmental biology to tumor perfusion studies. Studies using these methods can be classified based on whether they use artificial tracers or red blood cells to visualize the fluid motion. We here present the first direct comparison in vivo of both methods. For high magnification cases, the experiments using red blood cells strongly underestimate the flow (up to 50% in the present case), as compared to the tracer results. For medium magnification cases, the results from both methods are indistinguishable as they give the same underestimation of the real velocities (approximately 33%, based on in vitro reference measurements). These results suggest that flow characteristics reported in literature cannot be compared without a careful evaluation of the imaging characteristics. A method to predict the expected flow averaging behavior for a particular facility is presented. PMID:23028878

  7. Automatic emissive probe apparatus for accurate plasma and vacuum space potential measurements

    Science.gov (United States)

    Jianquan, LI; Wenqi, LU; Jun, XU; Fei, GAO; Younian, WANG

    2018-02-01

    We have developed an automatic emissive probe apparatus based on the improved inflection point method of the emissive probe for accurate measurements of both plasma potential and vacuum space potential. The apparatus consists of a computer controlled data acquisition card, a working circuit composed by a biasing unit and a heating unit, as well as an emissive probe. With the set parameters of the probe scanning bias, the probe heating current and the fitting range, the apparatus can automatically execute the improved inflection point method and give the measured result. The validity of the automatic emissive probe apparatus is demonstrated in a test measurement of vacuum potential distribution between two parallel plates, showing an excellent accuracy of 0.1 V. Plasma potential was also measured, exhibiting high efficiency and convenient use of the apparatus for space potential measurements.

  8. Accurate measurement of microscopic forces and torques using optical tweezers

    Directory of Open Access Journals (Sweden)

    Andrew Forbes

    2011-09-01

    Full Text Available It is now well known that matter may be trapped by optical fields with high intensity gradients. Once trapped, it is then possible to manipulate microscopic particles using such optical fields, in so-called optical tweezers. Such optical trapping and tweezing systems have found widespread application across diverse fields in science, from applied biology to fundamental physics. In this article we outline the design and construction of an optical trapping and tweezing system, and show how the resulting interaction of the laser light with microscopic particles may be understood in terms of the transfer of linear and angular momentum of light. We demonstrate experimentally the use of our optical tweezing configuration for the measurement of microscopic forces and torques. In particular, we make use of digital holography to create so-called vortex laser beams, capable of transferring orbital angular momentum to particles. The use of such novel laser beams in an optical trapping and tweezing set-up allows for the control of biological species at the single-cell level.

  9. Numerical assessment of accurate measurements of laminar flame speed

    Science.gov (United States)

    Goulier, Joules; Bizon, Katarzyna; Chaumeix, Nabiha; Meynet, Nicolas; Continillo, Gaetano

    2016-12-01

    In combustion, the laminar flame speed constitutes an important parameter that reflects the chemistry of oxidation for a given fuel, along with its transport and thermal properties. Laminar flame speeds are used (i) in turbulent models used in CFD codes, and (ii) to validate detailed or reduced mechanisms, often derived from studies using ideal reactors and in diluted conditions as in jet stirred reactors and in shock tubes. End-users of such mechanisms need to have an assessment of their capability to predict the correct heat released by combustion in realistic conditions. In this view, the laminar flame speed constitutes a very convenient parameter, and it is then very important to have a good knowledge of the experimental errors involved with its determination. Stationary configurations (Bunsen burners, counter-flow flames, heat flux burners) or moving flames (tubes, spherical vessel, soap bubble) can be used. The spherical expanding flame configuration has recently become popular, since it can be used at high pressures and temperatures. With this method, the flame speed is not measured directly, but derived through the recording of the flame radius. The method used to process the radius history will have an impact on the estimated flame speed. Aim of this work is to propose a way to derive the laminar flame speed from experimental recording of expanding flames, and to assess the error magnitude.

  10. Accurate measurements of local skin friction coefficient using hot-wire anemometry

    Science.gov (United States)

    Hutchins, Nick; Choi, Kwing-So

    2002-05-01

    The practicality and accuracy of many existing methods of local skin friction measurement suffer when the boundary layer flow under consideration is non-canonical. Such shortcomings are exacerbated in three-dimensional flows, by the necessity to map local cf over a wider area in order to characterise fully the contribution to global skin friction. These problems have led the authors to seek novel experimental methods of cf measurement. The technique proposed herein utilises velocity measurements made using hot-wire anemometry combined with accurate positioning of the sensor element in respect to the test surface. In essence it is proposed that the local skin friction can be evaluated via a single velocity measurement made at a known wall-normal distance within the linear region of the viscous sublayer. This technique relies on accurate probe positioning, and two methods of achieving this are outlined. A study of the hot-wire characteristics in near-wall proximity has revealed a previously unnoticed feature corresponding to probe-wall contact. It is shown that this anomaly can be used as a positional flag to accurately locate the aerodynamic origin of the hot-wire sensor. A second technique using a laser triangulation displacement sensor is also outlined. Both positional techniques are shown to offer positioning to a sufficient level of accuracy for the proposed cf measurement technique. Single-point local cf measurement is tested experimentally, demonstrating the improved repeatability and standard error as predicted by initial error analysis. In this way it is shown that a single 90 s velocity sample coupled with accurate wall positioning can define local cf to a standard error of σcf≈1.0%. Analysis of error contributions reveals that longer sampling periods can realise even greater accuracy. The proposed technique is also used to measure local cf in a three-dimensional boundary layer where micro-vortex generators have introduced large-scale spanwise

  11. Accurate measurement of gene copy number for human alpha-defensin DEFA1A3.

    Science.gov (United States)

    Khan, Fayeza F; Carpenter, Danielle; Mitchell, Laura; Mansouri, Omniah; Black, Holly A; Tyson, Jess; Armour, John A L

    2013-10-20

    Multi-allelic copy number variants include examples of extensive variation between individuals in the copy number of important genes, most notably genes involved in immune function. The definition of this variation, and analysis of its impact on function, has been hampered by the technical difficulty of large-scale but accurate typing of genomic copy number. The copy-variable alpha-defensin locus DEFA1A3 on human chromosome 8 commonly varies between 4 and 10 copies per diploid genome, and presents considerable challenges for accurate high-throughput typing. In this study, we developed two paralogue ratio tests and three allelic ratio measurements that, in combination, provide an accurate and scalable method for measurement of DEFA1A3 gene number. We combined information from different measurements in a maximum-likelihood framework which suggests that most samples can be assigned to an integer copy number with high confidence, and applied it to typing 589 unrelated European DNA samples. Typing the members of three-generation pedigrees provided further reassurance that correct integer copy numbers had been assigned. Our results have allowed us to discover that the SNP rs4300027 is strongly associated with DEFA1A3 gene copy number in European samples. We have developed an accurate and robust method for measurement of DEFA1A3 copy number. Interrogation of rs4300027 and associated SNPs in Genome-Wide Association Study SNP data provides no evidence that alpha-defensin copy number is a strong risk factor for phenotypes such as Crohn's disease, type I diabetes, HIV progression and multiple sclerosis.

  12. The tap test- an accurate First-line test for fetal lung maturity testing ...

    African Journals Online (AJOL)

    Objective. To determine the accuracy of near-patient and laboratory- based fetal lung maturity tests in predicting the need for neonatal ventilation. Design. A prospective descriptive study. Subjects. One hundred high-risk obstetric patients where confirmation of fetal lung maturity would initiate delivery. Methods. Fetal weight ...

  13. How accurate is an LCD screen version of the Pelli-Robson test?

    Science.gov (United States)

    Zeri, Fabrizio; Calcatelli, Paolo; Funaro, Eleonora; Martelli, Marialuisa; Naroo, Shehzad A

    2017-06-21

    To evaluate the accuracy and repeatability of a computer-generated Pelli-Robson test displayed on liquid crystal display (LCD) systems compared to a standard Pelli-Robson chart. Two different randomized crossover experiments were carried out for two different LCD systems for 32 subjects: 6 females and 10 males (40.5 ± 13.0 years) and 9 females and 7 males (27.8 ± 12.2 years), respectively, in the first and second experiment. Two repeated measurements were taken with the printed Pelli-Robson test and with the LCDs at 1 and 3 m. To test LCD reliability, measurements were repeated after 1 week. In Experiment 1, contrast sensitivity (CS) measured with LCD1 resulted significantly higher than Pelli-Robson both at 1 and at 3 m of about 0.20 log 1/C in both eyes (p LCD1 measures. LCD1 measurements showed reasonable repeatability: ICC was 0.83 and 0.65 at 1 and 3 m, respectively. In Experiment 2, CS measured with LCD2 resulted significantly lower than Pelli-Robson both at 1 and at 3 m of about 0.10 log 1/C in both eyes (p LCD2 measures. LCD2 measurements showed sufficient repeatability: ICC resulted 0.51 and 0.65 at 1 and 3 m, respectively. Computer-generated versions of Pelli-Robson test, displayed on LCD systems, do not provide accurate results compared to classic Pelli-Robson printed version. Clinicians should consider that Pelli-Robson computer-generated versions could be non-interchangeable to the printed version.

  14. Sitting and standing blood pressure measurements are not accurate for the diagnosis of orthostatic hypotension.

    LENUS (Irish Health Repository)

    Cooke, J

    2012-01-31

    INTRODUCTION: Orthostatic hypotension (OH) is associated with troublesome symptoms and increased mortality. It is treatable and deserving of accurate diagnosis. This can be time consuming. The current reference standard for its diagnosis is head-up tilt (HUT) testing with continuous beat-to-beat plethysmography. Our objective was to assess the accuracy of sit-stand testing with semi-automatic sphygmomanometry for the diagnosis of OH. DESIGN: Retrospective test of diagnostic accuracy. METHODS: This was a retrospective study performed using a database maintained by a busy syncope unit. HUT testing was performed using an automated tilt table with Finometer monitoring. A 3 min 70 degrees HUT was performed following 5 min supine. Sitting blood pressure (BP) was measured following 3 min rest. Standing BP was measured within 30 s of assuming the upright posture. The results of sit-stand testing were compared with HUT testing as a reference standard. Both tests happened within 5 min of each other and patients underwent no intervention between tests. RESULTS: From a total of 1452 consecutive HUTs, we identified 730 with pre-test measures of sitting and standing BP. The mean age of this group was 70.57 years (SD = 15.1), 62% were female. The sensitivity of sit-stand testing was calculated as 15.5%, specificity as 89.9%, positive predictive value as 61.7%, negative predictive value as 50.2% and the likelihood ratio as 1.6. The area under the Receiver Operator Curve was 0.564. CONCLUSION: We have demonstrated that sit-stand testing for OH has very low diagnostic accuracy. We recommend that the more time-consuming reference standard method of diagnosis be used if the condition is suspected.

  15. Accurate measuring temperature by infrared thermal imaging system in vacuum and cryogenic environment

    Science.gov (United States)

    Shang, Yonghong; Tao, Dongxing; Hou, Yaqing; Wang, Jing; Pei, Yifei

    2018-01-01

    Infrared thermal imaging technology uses the detector to receive infrared radiation from the measured object, and the object temperature distribution will be changed into a visual image by signal processing system. The accuracy of measuring temperature will be affected by the surface emission rate, reflectivity, atmospheric attenuation, and background radiation and environmental effect under normal temperature and pressure conditions. In order to realize the accurate temperature measurement under the condition of ultra-high vacuum and cryogenic environment, the general formula of the theoretic temperature of measured object surface is deduced, which based on the principle of thermal radiation and temperature measurement by infrared thermal imager. In this paper, the impact factors of temperature measurement accuracy of long-wave infrared thermal imaging system under those conditions are analyzed, and various theoretical numerical value of factors are plotted on the curve of precious accuracy temperature measurement. The results of analysis for the thermal imaging system will improve temperature measurement precision in vacuum thermal test, which have active practical significance.

  16. Rapid and accurate biofuel moisture content gauging using magnetic resonance measurement technology

    Energy Technology Data Exchange (ETDEWEB)

    Jaervinen, T.

    2013-04-15

    Biomass is extensively utilised in energy production and as a raw material, such as for the production of liquid biofuels. All those processes will benefit if the moisture content of bio material is known in advance as accurately as possible under transient circumstances. Biofuel trade is increasingly based on the calorific value of fuels. In the first step, this also increases the need for rapid and accurate moisture content determination. During the last few years, large biofuel standardisation has been implemented, emphasising biofuel quality control at all stages of the utilisation chain. In principle, the moisture instrumental measurement can be utilised by many technologies and procedures. Typical techniques are infrared, radiofrequency, microwave, radiometric, electrical conductivity, capacitance, and impedance. Nuclear magnetic resonance (MR) and thermal neutron absorption are also applied. The MR measurement principle has been known and utilised already since the early 1950s. It has become the basic instrumental analysis tool in chemistry. It is also well-known as a very accurate method for analysing most compounds, especially substances containing hydrogen. The utilisation of MR metering is expanded extensively to medical diagnostics as a form of magnetic resonance imaging (MRI). Because of the precision of the MR principle, there have for a long time been efforts to apply it in new and different areas, and to make more user-friendly, smaller, and even portable devices. Such a device was designed by Vaisala a few years ago. VTT has utilised Vaisala's MR prototype for approximately one year for moisture content measurement of different biofuels. The first step in the use of an MR device for moisture determination was the definition of its measurement accuracy compared to the standard method (EN 14774). Those tests proved that the absolute precision seems to be comparable to the standard moisture content measurement method. It was also found out that

  17. Standardized Testing of Phasor Measurement Units

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Kenneth E.; Faris, Anthony J.; Hauer, John F.

    2006-05-31

    This paper describes a set of tests used to determine Phasor Measurement Unit (PMU) measurement characteristics under steady state and dynamic conditions. The methodology is repeatable, comparable among test facilities, and can be performed at any facility with commonly available relay and standard test equipment. The methodology is based upon using test signals that are mathematically generated from a signal model and played into the PMU with precise GPS synchronization. Timing flags included with the test signal provide correlate the test signals and the PMU output. This allows accurate comparison of the phasor model with the value estimated by the PMU for accurate performance analysis. The timing flags also facilitate programmed plot and report generation.

  18. A highly accurate inclusive cancer screening test using Caenorhabditis elegans scent detection.

    Directory of Open Access Journals (Sweden)

    Takaaki Hirotsu

    Full Text Available Early detection and treatment are of vital importance to the successful eradication of various cancers, and development of economical and non-invasive novel cancer screening systems is critical. Previous reports using canine scent detection demonstrated the existence of cancer-specific odours. However, it is difficult to introduce canine scent recognition into clinical practice because of the need to maintain accuracy. In this study, we developed a Nematode Scent Detection Test (NSDT using Caenorhabditis elegans to provide a novel highly accurate cancer detection system that is economical, painless, rapid and convenient. We demonstrated wild-type C. elegans displayed attractive chemotaxis towards human cancer cell secretions, cancer tissues and urine from cancer patients but avoided control urine; in parallel, the response of the olfactory neurons of C. elegans to the urine from cancer patients was significantly stronger than to control urine. In contrast, G protein α mutants and olfactory neurons-ablated animals were not attracted to cancer patient urine, suggesting that C. elegans senses odours in urine. We tested 242 samples to measure the performance of the NSDT, and found the sensitivity was 95.8%; this is markedly higher than that of other existing tumour markers. Furthermore, the specificity was 95.0%. Importantly, this test was able to diagnose various cancer types tested at the early stage (stage 0 or 1. To conclude, C. elegans scent-based analyses might provide a new strategy to detect and study disease-associated scents.

  19. A highly accurate inclusive cancer screening test using Caenorhabditis elegans scent detection.

    Science.gov (United States)

    Hirotsu, Takaaki; Sonoda, Hideto; Uozumi, Takayuki; Shinden, Yoshiaki; Mimori, Koshi; Maehara, Yoshihiko; Ueda, Naoko; Hamakawa, Masayuki

    2015-01-01

    Early detection and treatment are of vital importance to the successful eradication of various cancers, and development of economical and non-invasive novel cancer screening systems is critical. Previous reports using canine scent detection demonstrated the existence of cancer-specific odours. However, it is difficult to introduce canine scent recognition into clinical practice because of the need to maintain accuracy. In this study, we developed a Nematode Scent Detection Test (NSDT) using Caenorhabditis elegans to provide a novel highly accurate cancer detection system that is economical, painless, rapid and convenient. We demonstrated wild-type C. elegans displayed attractive chemotaxis towards human cancer cell secretions, cancer tissues and urine from cancer patients but avoided control urine; in parallel, the response of the olfactory neurons of C. elegans to the urine from cancer patients was significantly stronger than to control urine. In contrast, G protein α mutants and olfactory neurons-ablated animals were not attracted to cancer patient urine, suggesting that C. elegans senses odours in urine. We tested 242 samples to measure the performance of the NSDT, and found the sensitivity was 95.8%; this is markedly higher than that of other existing tumour markers. Furthermore, the specificity was 95.0%. Importantly, this test was able to diagnose various cancer types tested at the early stage (stage 0 or 1). To conclude, C. elegans scent-based analyses might provide a new strategy to detect and study disease-associated scents.

  20. Measurement of caudate nucleus area - a more accurate measurement for Huntington's disease?

    International Nuclear Information System (INIS)

    Wardlaw, J.M.; Abernethy, L.J.; Sellar, R.J.

    1991-01-01

    Caudate nucleus atrophy occurs in Huntington's disease and methods of measuring this have been described using axial CT, but these are indirect and lack sensitivity. We measured caudate nucleus area (blind to the subjects' clinical state) in 30 subjects with or at risk of Huntington's disease, and in 100 normal age matched controls. Fifteen subjects with established symptomatic Huntington's disease, 3 with early symptoms, and 3 presymptomatic subjects (2 showing a high probability for the Huntington's disease gene on genetic testing, and one who has since developed symptoms) were correctly identified. Three normal (gene negative) family members were also correctly identified. Outcome is awaited in 6. CT caudate area measurement is simple and reproducible and we have found it to be a useful confirmatory test for Huntington's disease. (orig.)

  1. Accurate and fast 3D surface measurement with temporal-spatial binary encoding structured illumination.

    Science.gov (United States)

    Zhu, Jiangping; Zhou, Pei; Su, Xianyu; You, Zhisheng

    2016-12-12

    Balancing the accuracy and speed for 3D surface measurement of object is crucial in many important applications. Binary encoding pattern utilizing the high-speed image switching rate of digital mirror device (DMD)-based projector could be used as the candidate for fast even high-speed 3D measurement, but current most schemes only enable the measurement speed, which limit their application scopes. In this paper, we present a binary encoding method and develop an experimental system aiming to solve such a situation. Our approach encodes one computer-generated standard 8 bit sinusoidal fringe pattern into multiple binary patterns (sequence) with designed temporal-spatial binary encoding tactics. The binary pattern sequence is then high-speed and in-focus projected onto the surface of tested object, and then captured by means of temporal-integration imaging to form one sinusoidal fringe image. Further the combination of phase-shifting technique and temporal phase unwrapping algorithm leads to fast and accurate 3D measurement. The systematic accuracy better than 0.08mm is achievable. The measurement results with mask and palm are given to confirm the feasibility.

  2. Accurate measurement of the electron beam polarization in JLab Hall A using Compton polarimetry

    International Nuclear Information System (INIS)

    Escoffier, S.; Bertin, P.Y.; Brossard, M.; Burtin, E.; Cavata, C.; Colombel, N.; Jager, C.W. de; Delbart, A.; Lhuillier, D.; Marie, F.; Mitchell, J.; Neyret, D.; Pussieux, T.

    2005-01-01

    A major advance in accurate electron beam polarization measurement has been achieved at Jlab Hall A with a Compton polarimeter based on a Fabry-Perot cavity photon beam amplifier. At an electron energy of 4.6GeV and a beam current of 40μA, a total relative uncertainty of 1.5% is typically achieved within 40min of data taking. Under the same conditions monitoring of the polarization is accurate at a level of 1%. These unprecedented results make Compton polarimetry an essential tool for modern parity-violation experiments, which require very accurate electron beam polarization measurements

  3. Measuring Test Measurement Error: A General Approach

    Science.gov (United States)

    Boyd, Donald; Lankford, Hamilton; Loeb, Susanna; Wyckoff, James

    2013-01-01

    Test-based accountability as well as value-added asessments and much experimental and quasi-experimental research in education rely on achievement tests to measure student skills and knowledge. Yet, we know little regarding fundamental properties of these tests, an important example being the extent of measurement error and its implications for…

  4. Comparison of thermistor linearization techniques for accurate temperature measurement in phase change materials

    OpenAIRE

    Stankovic, S. B.; Kyriacou, P. A.

    2011-01-01

    Alternate energy technologies are developing rapidly in the recent years. A significant part of this trend is the development of different phase change materials (PCMs). Proper utilization of PCMs requires accurate thermal characterization. There are several methodologies used in this field. This paper stresses the importance of accurate temperature measurements during the implementation of T-history method. Since the temperature sensor size is also important thermistors have been selected as...

  5. Accurate Measurement of Indoor Radon Concentration using a Low-Effective Volume Radon Monitor.

    Science.gov (United States)

    Tanaka, Aya; Minami, Nodoka; Yasuoka, Yumi; Iimoto, Takeshi; Omori, Yasutaka; Nagahama, Hiroyuki; Muto, Jun; Mukai, Takahiro

    2017-12-01

    AlphaGUARD is a low-effective volume detector and one of the most popular portable radon monitors which is currently available. This study investigated whether AlphaGUARD can accurately measure the variable indoor radon levels. The consistency of the radon-concentration data obtained by AlphaGUARD is evaluated against simultaneous measurements by two other monitors (each ~10 times more sensitive than AlphaGUARD). When accurately measuring radon concentration with AlphaGUARD, we found that the net counts of the AlphaGUARD were required of at least 500 counts, <25% of the relative percent difference. AlphaGUARD can provide accurate measurements of radon concentration for the world average level (~50 Bq m-3) and the reference level of workplace (1000 Bq m-3), using integrated data over at least 3 h and 10 min, respectively. © The Author 2017. Published by Oxford University Press.

  6. Measuring Accurate Body Parameters of Dressed Humans with Large-Scale Motion Using a Kinect Sensor

    Directory of Open Access Journals (Sweden)

    Sidan Du

    2013-08-01

    Full Text Available Non-contact human body measurement plays an important role in surveillance, physical healthcare, on-line business and virtual fitting. Current methods for measuring the human body without physical contact usually cannot handle humans wearing clothes, which limits their applicability in public environments. In this paper, we propose an effective solution that can measure accurate parameters of the human body with large-scale motion from a Kinect sensor, assuming that the people are wearing clothes. Because motion can drive clothes attached to the human body loosely or tightly, we adopt a space-time analysis to mine the information across the posture variations. Using this information, we recover the human body, regardless of the effect of clothes, and measure the human body parameters accurately. Experimental results show that our system can perform more accurate parameter estimation on the human body than state-of-the-art methods.

  7. The importance of accurate meteorological input fields and accurate planetary boundary layer parameterizations, tested against ETEX-1

    International Nuclear Information System (INIS)

    Brandt, J.; Ebel, A.; Elbern, H.; Jakobs, H.; Memmesheimer, M.; Mikkelsen, T.; Thykier-Nielsen, S.; Zlatev, Z.

    1997-01-01

    Atmospheric transport of air pollutants is, in principle, a well understood process. If information about the state of the atmosphere is given in all details (infinitely accurate information about wind speed, etc.) and infinitely fast computers are available then the advection equation could in principle be solved exactly. This is, however, not the case: discretization of the equations and input data introduces some uncertainties and errors in the results. Therefore many different issues have to be carefully studied in order to diminish these uncertainties and to develop an accurate transport model. Some of these are e.g. the numerical treatment of the transport equation, accuracy of the mean meteorological input fields and parameterizations of sub-grid scale phenomena (as e.g. parameterizations of the 2 nd and higher order turbulence terms in order to reach closure in the perturbation equation). A tracer model for studying transport and dispersion of air pollution caused by a single but strong source is under development. The model simulations from the first ETEX release illustrate the differences caused by using various analyzed fields directly in the tracer model or using a meteorological driver. Also different parameterizations of the mixing height and the vertical exchange are compared. (author)

  8. Chest Radiograph Measurement Technique Facilitates Accurate Bedside Peripherally Inserted Central Catheter Placement in Children.

    Science.gov (United States)

    Ramamurthi, Aishu; Chick, Jeffrey Forris Beecham; Srinivasa, Rajiv N; Hage, Anthony N; Grove, Jason J; Gemmete, Joseph J; Johnson, Timothy D; Srinivasa, Ravi N

    2018-03-01

    To report the chest radiograph measurement technique for placing bedside peripherally inserted central catheters (PICCs). Two hundred and thirty-two consecutive pediatric patients, mean age of 56.3 months (range: 0-203 months), underwent PICC placement from January 2015 to May 2017 (28 months) with a total of 232 PICCs placed. Measurements were taken from the cavoatrial junction to clavicle, clavicle to medial margin of mid-humeral head, and medial margin of mid-humeral head to mid-humerus. The difference between total radiographic measured length and actual PICC length was then calculated, and the percent difference (from actual cut length) was recorded. An equivalence test was performed using the two, one-sided test method. Mean ± standard deviation cavoatrial junction to clavicle length was 5.29 ± 2.20 cm (range: 2.1-12.6 cm). Mean clavicle to shoulder length was 8.20 ± 3.59 cm (range: 3.23-19.06 cm). Mean shoulder to mid-humerus length was 7.88 ± 3.87 cm (range: 2.01-16.8 cm). Mean total radiographic measured length was 21.37 ± 9.19 cm (range: 7.42-43.6 cm). Mean actual cut PICC length was 20.64 ± 8.72 cm (range: 8.5-44 cm). The mean difference between predicted, or total radiographic measured length, and actual cut PICC length was 0.73 ± 2.51 (range: - 5.42-8.60 cm). The mean percent difference was 4.07 ± 12.65% (range: - 23.84-47.80%). An equivalence test rejected the null hypothesis of the true percent difference greater/less than ± 6.67% with a p value of 0.002. The chest radiograph measurement technique is an accurate method to determine catheter length for PICC placement at bedside in the pediatric population.

  9. Accurate Measurement of New Type Non-silicon Solar Cells’ Photoelectric Conversion Efficiency

    Science.gov (United States)

    Meng, Haifeng; Xiong, Limin; Zhang, Junchao; He, Yingwei; Zhang, Bifeng; Cai, Chuan

    2018-02-01

    Different from traditional silicon solar cells, new type non-silicon solar cells are composed of various kinds of materials, such as organic, perovskite, quantum dots and so on. They always show special performance in spectral responsivity, compatibility and stability, which brought great challenges for the accurate measurement of photoelectric conversion efficiency. We will illustrate a method for accurate efficiency measurement mainly in the view of metrology. Based on effective traceability and calibration of the standard value, a procedure for new type non-silicon solar cells’ efficiency measurement would be proposed. Main influencing factors such as spectral mismatch will also be analysed. Hope to provide a reference method for the accurate characterization of the photo-electric properties of various new types of solar cells.

  10. Accurate measurements of the acoustical physical constants of synthetic alpha-quartz for SAW devices.

    Science.gov (United States)

    Kushibiki, Juin-ichi; Takanaga, Izumi; Nishiyama, Shouichi

    2002-01-01

    Accurate measurements of the acoustical physical constants (elastic constants, piezoelectric constants, dielectric constants, and density) of commercially available and widely used surface acoustic wave (SAW)-grade synthetic a-quartz are reported. The propagation directions and modes of bulk waves optimal for accurately determining the constants were selected through numerical calculations, and three principal X-, Y-, and Z-cut specimens and several rotated Y-cut specimens were prepared from a single crystal ingot to determine the constants and to confirm their accuracy. All of the constants were determined through highly accurate measurements of the longitudinal velocities, shear velocities, dielectric constants, and density. The velocity values measured for the specimens that were not used to determine the constants agreed well with those calculated from the determined constants, within a difference of +/- 0.20 m/s (+/- 0.004%).

  11. Accurate 3D kinematic measurement of temporomandibular joint using X-ray fluoroscopic images

    Science.gov (United States)

    Yamazaki, Takaharu; Matsumoto, Akiko; Sugamoto, Kazuomi; Matsumoto, Ken; Kakimoto, Naoya; Yura, Yoshiaki

    2014-04-01

    Accurate measurement and analysis of 3D kinematics of temporomandibular joint (TMJ) is very important for assisting clinical diagnosis and treatment of prosthodontics and orthodontics, and oral surgery. This study presents a new 3D kinematic measurement technique of the TMJ using X-ray fluoroscopic images, which can easily obtain the TMJ kinematic data in natural motion. In vivo kinematics of the TMJ (maxilla and mandibular bone) is determined using a feature-based 2D/3D registration, which uses beads silhouette on fluoroscopic images and 3D surface bone models with beads. The 3D surface models of maxilla and mandibular bone with beads were created from CT scans data of the subject using the mouthpiece with the seven strategically placed beads. In order to validate the accuracy of pose estimation for the maxilla and mandibular bone, computer simulation test was performed using five patterns of synthetic tantalum beads silhouette images. In the clinical applications, dynamic movement during jaw opening and closing was conducted, and the relative pose of the mandibular bone with respect to the maxilla bone was determined. The results of computer simulation test showed that the root mean square errors were sufficiently smaller than 1.0 mm and 1.0 degree. In the results of clinical application, during jaw opening from 0.0 to 36.8 degree of rotation, mandibular condyle exhibited 19.8 mm of anterior sliding relative to maxillary articular fossa, and these measurement values were clinically similar to the previous reports. Consequently, present technique was thought to be suitable for the 3D TMJ kinematic analysis.

  12. The standard centrifuge method accurately measures vulnerability curves of long-vesselled olive stems.

    Science.gov (United States)

    Hacke, Uwe G; Venturas, Martin D; MacKinnon, Evan D; Jacobsen, Anna L; Sperry, John S; Pratt, R Brandon

    2015-01-01

    The standard centrifuge method has been frequently used to measure vulnerability to xylem cavitation. This method has recently been questioned. It was hypothesized that open vessels lead to exponential vulnerability curves, which were thought to be indicative of measurement artifact. We tested this hypothesis in stems of olive (Olea europea) because its long vessels were recently claimed to produce a centrifuge artifact. We evaluated three predictions that followed from the open vessel artifact hypothesis: shorter stems, with more open vessels, would be more vulnerable than longer stems; standard centrifuge-based curves would be more vulnerable than dehydration-based curves; and open vessels would cause an exponential shape of centrifuge-based curves. Experimental evidence did not support these predictions. Centrifuge curves did not vary when the proportion of open vessels was altered. Centrifuge and dehydration curves were similar. At highly negative xylem pressure, centrifuge-based curves slightly overestimated vulnerability compared to the dehydration curve. This divergence was eliminated by centrifuging each stem only once. The standard centrifuge method produced accurate curves of samples containing open vessels, supporting the validity of this technique and confirming its utility in understanding plant hydraulics. Seven recommendations for avoiding artefacts and standardizing vulnerability curve methodology are provided. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  13. Accurate microfour-point probe sheet resistance measurements on small samples

    DEFF Research Database (Denmark)

    Thorsteinsson, Sune; Wang, Fei; Petersen, Dirch Hjorth

    2009-01-01

    We show that accurate sheet resistance measurements on small samples may be performed using microfour-point probes without applying correction factors. Using dual configuration measurements, the sheet resistance may be extracted with high accuracy when the microfour-point probes are in proximity...... of a mirror plane on small samples with dimensions of a few times the probe pitch. We calculate theoretically the size of the “sweet spot,” where sufficiently accurate sheet resistances result and show that even for very small samples it is feasible to do correction free extraction of the sheet resistance...

  14. The effect of external dynamic loads on the lifetime of rolling element bearings: accurate measurement of the bearing behaviour

    International Nuclear Information System (INIS)

    Jacobs, W; Boonen, R; Sas, P; Moens, D

    2012-01-01

    Accurate prediction of the lifetime of rolling element bearings is a crucial step towards a reliable design of many rotating machines. Recent research emphasizes an important influence of external dynamic loads on the lifetime of bearings. However, most lifetime calculations of bearings are based on the classical ISO 281 standard, neglecting this influence. For bearings subjected to highly varying loads, this leads to inaccurate estimations of the lifetime, and therefore excessive safety factors during the design and unexpected failures during operation. This paper presents a novel test rig, developed to analyse the behaviour of rolling element bearings subjected to highly varying loads. Since bearings are very precise machine components, their motion can only be measured in an accurately controlled environment. Otherwise, noise from other components and external influences such as temperature variations will dominate the measurements. The test rig is optimised to perform accurate measurements of the bearing behaviour. Also, the test bearing is fitted in a modular structure, which guarantees precise mounting and allows testing different types and sizes of bearings. Finally, a fully controlled multi-axial static and dynamic load is imposed on the bearing, while its behaviour is monitored with capacitive proximity probes.

  15. Importance of accurate measurements in nutrition research: dietary flavonoids as a case study

    Science.gov (United States)

    Accurate measurements of the secondary metabolites in natural products and plant foods are critical to establishing diet/health relationships. There are as many as 50,000 secondary metabolites which may influence human health. Their structural and chemical diversity present a challenge to analytic...

  16. Toward Accurate Measurement of Participation: Rethinking the Conceptualization and Operationalization of Participatory Evaluation

    Science.gov (United States)

    Daigneault, Pierre-Marc; Jacob, Steve

    2009-01-01

    While participatory evaluation (PE) constitutes an important trend in the field of evaluation, its ontology has not been systematically analyzed. As a result, the concept of PE is ambiguous and inadequately theorized. Furthermore, no existing instrument accurately measures stakeholder participation. First, this article attempts to overcome these…

  17. An investigation of highly accurate and precise robotic hole measurements using non-contact devices

    Directory of Open Access Journals (Sweden)

    Usman Zahid

    2016-01-01

    Full Text Available Industrial robots arms are widely used in manufacturing industry because of their support for automation. However, in metrology, robots have had limited application due to their insufficient accuracy. Even using error compensation and calibration methods, robots are not effective for micrometre (μm level metrology. Non-contact measurement devices can potentially enable the use of robots for highly accurate metrology. However, the use of such devices on robots has not been investigated. The research work reported in this paper explores the use of different non-contact measurement devices on an industrial robot. The aim is to experimentally investigate the effects of robot movements on the accuracy and precision of measurements. The focus has been on assessing the ability to accurately measure various geometric and surface parameters of holes despite the inherent inaccuracies of industrial robot. This involves the measurement of diameter, roundness and surface roughness. The study also includes scanning of holes for measuring internal features such as start and end point of a taper. Two different non-contact measurement devices based on different technologies are investigated. Furthermore, effects of eccentricity, vibrations and thermal variations are also assessed. The research contributes towards the use of robots for highly accurate and precise robotic metrology.

  18. An easy way to measure accurately the direct magnetoelectric voltage coefficient of thin film devices

    Science.gov (United States)

    Poullain, Gilles; More-Chevalier, Joris; Cibert, Christophe; Bouregba, Rachid

    2017-01-01

    TbxDy1-xFe2/Pt/Pb(Zrx, Ti1-x)O3 thin films were grown on Pt/TiO2/SiO2/Si substrate by multi-target sputtering. The magnetoelectric voltage coefficient αΗΜΕ was determined at room temperature using a lock-in amplifier. By adding, in series in the circuit, a capacitor of the same value as that of the device under test, we were able to demonstrate that the magnetoelectric device behaves as a voltage source. Furthermore, a simple way to subtract the stray voltage arising from the flow of eddy currents in the measurement set-up, is proposed. This allows the easy and accurate determination of the true magnetoelectric voltage coefficient. A large αΗΜΕ of 8.3 V/cm. Oe was thus obtained for a Terfenol-D/Pt/PZT thin film device, without DC magnetic field nor mechanical resonance.

  19. Accurate determination of gain and radiation patterns by radar cross-section measurements

    DEFF Research Database (Denmark)

    Appel-Hansen, Jørgen

    1979-01-01

    Using a two-port network and geometrical interpretation of equations involved in antenna scattering, it can be derived that antenna characteristics may be determined in properly designed scattering measurements. As an alternative to this approach it is shown that measurement procedures for gain...... to be highly accurate. These general conclusions are well corroborated by experimental data on a standard gain horn. Sources of errors are outlined and compared with sources of errors in conventional techniques....

  20. The use of multiple imputation for the accurate measurements of individual feed intake by electronic feeders.

    Science.gov (United States)

    Jiao, S; Tiezzi, F; Huang, Y; Gray, K A; Maltecca, C

    2016-02-01

    Obtaining accurate individual feed intake records is the key first step in achieving genetic progress toward more efficient nutrient utilization in pigs. Feed intake records collected by electronic feeding systems contain errors (erroneous and abnormal values exceeding certain cutoff criteria), which are due to feeder malfunction or animal-feeder interaction. In this study, we examined the use of a novel data-editing strategy involving multiple imputation to minimize the impact of errors and missing values on the quality of feed intake data collected by an electronic feeding system. Accuracy of feed intake data adjustment obtained from the conventional linear mixed model (LMM) approach was compared with 2 alternative implementations of multiple imputation by chained equation, denoted as MI (multiple imputation) and MICE (multiple imputation by chained equation). The 3 methods were compared under 3 scenarios, where 5, 10, and 20% feed intake error rates were simulated. Each of the scenarios was replicated 5 times. Accuracy of the alternative error adjustment was measured as the correlation between the true daily feed intake (DFI; daily feed intake in the testing period) or true ADFI (the mean DFI across testing period) and the adjusted DFI or adjusted ADFI. In the editing process, error cutoff criteria are used to define if a feed intake visit contains errors. To investigate the possibility that the error cutoff criteria may affect any of the 3 methods, the simulation was repeated with 2 alternative error cutoff values. Multiple imputation methods outperformed the LMM approach in all scenarios with mean accuracies of 96.7, 93.5, and 90.2% obtained with MI and 96.8, 94.4, and 90.1% obtained with MICE compared with 91.0, 82.6, and 68.7% using LMM for DFI. Similar results were obtained for ADFI. Furthermore, multiple imputation methods consistently performed better than LMM regardless of the cutoff criteria applied to define errors. In conclusion, multiple imputation

  1. Novel technique to accurately measure femoral diameter using a Thomas splint.

    Science.gov (United States)

    Liew, Ignatius; Qureshi, Mobeen; Joseph, Jibu; Bailey, Oliver

    2017-11-01

    During surgical management of femoral shaft fractures, difficulties arise when treating patients with narrow femoral diaphyseal canals, such as young patients and those with dysplastic femurs secondary to underlying pathology. Accurate pre-operative assessment of the femoral diaphyseal canal diameter would allow the surgeon to plan surgical technique and ensure appropriate equipment was available, such as narrow, unreamed or paediatric sized nails. When secured to the patient both longitudinal rods of the main Thomas Splint component lie parallel with the femoral shaft and horizontal to the radiographic x-ray plate. The diameter of these rods are 13mm (Adult and paediatric). Using the calibration tool, we calibrate the diameter of the Thomas Splint to 13mm, accurately measuring any further detail on that radiograph, such as the diaphyseal canal diameter. Accurate knowledge pre-operatively of radiographic measurements is highly valuable to the operating surgeon. This technique can accurately measure femoral canal diameter using the Thomas splint, negates the requirement for a calibration marker, is reproducible, easy to perform, and is indispensible when faced with a patient with a narrow femoral canal in a diaphyseal femoral fracture. (181 words). Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  2. Defining Allowable Physical Property Variations for High Accurate Measurements on Polymer Parts

    DEFF Research Database (Denmark)

    Mohammadi, Ali; Sonne, Mads Rostgaard; Madruga, Daniel González

    2015-01-01

    Measurement conditions and material properties have a significant impact on the dimensions of a part, especially for polymers parts. Temperature variation causes part deformations that increase the uncertainty of the measurement process. Current industrial tolerances of a few micrometres demand...... high accurate measurements in non-controlled ambient. Most of polymer parts are manufactured by injection moulding and their inspection is carried out after stabilization, around 200 hours. The overall goal of this work is to reach ±5μm in uncertainty measurements a polymer products which...

  3. Multifrequency Excitation Method for Rapid and Accurate Dynamic Test of Micromachined Gyroscope Chips

    Directory of Open Access Journals (Sweden)

    Yan Deng

    2014-10-01

    Full Text Available A novel multifrequency excitation (MFE method is proposed to realize rapid and accurate dynamic testing of micromachined gyroscope chips. Compared with the traditional sweep-frequency excitation (SFE method, the computational time for testing one chip under four modes at a 1-Hz frequency resolution and 600-Hz bandwidth was dramatically reduced from 10 min to 6 s. A multifrequency signal with an equal amplitude and initial linear-phase-difference distribution was generated to ensure test repeatability and accuracy. The current test system based on LabVIEW using the SFE method was modified to use the MFE method without any hardware changes. The experimental results verified that the MFE method can be an ideal solution for large-scale dynamic testing of gyroscope chips and gyroscopes.

  4. Accurate mass replacement method for the sediment concentration measurement with a constant volume container

    Science.gov (United States)

    Ban, Yunyun; Chen, Tianqin; Yan, Jun; Lei, Tingwu

    2017-04-01

    The measurement of sediment concentration in water is of great importance in soil erosion research and soil and water loss monitoring systems. The traditional weighing method has long been the foundation of all the other measuring methods and instrument calibration. The development of a new method to replace the traditional oven-drying method is of interest in research and practice for the quick and efficient measurement of sediment concentration, especially field measurements. A new method is advanced in this study for accurately measuring the sediment concentration based on the accurate measurement of the mass of the sediment-water mixture in the confined constant volume container (CVC). A sediment-laden water sample is put into the CVC to determine its mass before the CVC is filled with water and weighed again for the total mass of the water and sediments in the container. The known volume of the CVC, the mass of sediment-laden water, and sediment particle density are used to calculate the mass of water, which is replaced by sediments, therefore sediment concentration of the sample is calculated. The influence of water temperature was corrected by measuring water density to determine the temperature of water before measurements were conducted. The CVC was used to eliminate the surface tension effect so as to obtain the accurate volume of water and sediment mixture. Experimental results showed that the method was capable of measuring the sediment concentration from 0.5 up to 1200 kg m-3. A good liner relationship existed between the designed and measured sediment concentrations with all the coefficients of determination greater than 0.999 and the averaged relative error less than 0.2%. All of these seem to indicate that the new method is capable of measuring a full range of sediment concentration above 0.5 kg m-3 to replace the traditional oven-drying method as a standard method for evaluating and calibrating other methods.

  5. Defining allowable physical property variations for high accurate measurements on polymer parts

    Science.gov (United States)

    Mohammadi, A.; Sonne, M. R.; Madruga, D. G.; De Chiffre, L.; Hattel, J. H.

    2016-06-01

    Measurement conditions and material properties have a significant impact on the dimensions of a part, especially for polymers parts. Temperature variation causes part deformations that increase the uncertainty of the measurement process. Current industrial tolerances of a few micrometres demand high accurate measurements in non-controlled ambient. Most of polymer parts are manufactured by injection moulding and their inspection is carried out after stabilization, around 200 hours. The overall goal of this work is to reach ±5μm in uncertainty measurements a polymer products which is a challenge in today`s production and metrology environments. The residual deformations in polymer products at room temperature after injection molding are important when micrometer accuracy needs to be achieved. Numerical modelling can give a valuable insight to what is happening in the polymer during cooling down after injection molding. In order to obtain accurate simulations, accurate inputs to the model are crucial. In reality however, the material and physical properties will have some variations. Although these variations may be small, they can act as a source of uncertainty for the measurement. In this paper, we investigated how big the variation in material and physical properties are allowed in order to reach the 5 μm target on the uncertainty.

  6. Progress Toward Accurate Measurements of Power Consumptions of DBD Plasma Actuators

    Science.gov (United States)

    Ashpis, David E.; Laun, Matthew C.; Griebeler, Elmer L.

    2012-01-01

    The accurate measurement of power consumption by Dielectric Barrier Discharge (DBD) plasma actuators is a challenge due to the characteristics of the actuator current signal. Micro-discharges generate high-amplitude, high-frequency current spike transients superimposed on a low-amplitude, low-frequency current. We have used a high-speed digital oscilloscope to measure the actuator power consumption using the Shunt Resistor method and the Monitor Capacitor method. The measurements were performed simultaneously and compared to each other in a time-accurate manner. It was found that low signal-to-noise ratios of the oscilloscopes used, in combination with the high dynamic range of the current spikes, make the Shunt Resistor method inaccurate. An innovative, nonlinear signal compression circuit was applied to the actuator current signal and yielded excellent agreement between the two methods. The paper describes the issues and challenges associated with performing accurate power measurements. It provides insights into the two methods including new insight into the Lissajous curve of the Monitor Capacitor method. Extension to a broad range of parameters and further development of the compression hardware will be performed in future work.

  7. New accurate measurements of neutron emission probabilities for relevant fission products

    Directory of Open Access Journals (Sweden)

    Agramunt J.

    2017-01-01

    Full Text Available We have performed new accurate measurements of the beta-delayed neutron emission probability for ten isotopes of the elements Y, Sb, Te and I. These are fission products that either have a significant contribution to the fraction of delayed neutrons in reactors or are relatively close to the path of the astrophysical r process. The measurements were performed with isotopically pure radioactive beams using a constant and high efficiency neutron counter and a low noise beta detector. Preliminary results are presented for six of the isotopes and compared with previous measurements and theoretical calculations.

  8. Borehole flowmeter logging for the accurate design and analysis of tracer tests.

    Science.gov (United States)

    Basiricò, Stefano; Crosta, Giovanni B; Frattini, Paolo; Villa, Alberto; Godio, Alberto

    2015-04-01

    Tracer tests often give ambiguous interpretations that may be due to the erroneous location of sampling points and/or the lack of flow rate measurements through the sampler. To obtain more reliable tracer test results, we propose a methodology that optimizes the design and analysis of tracer tests in a cross borehole mode by using vertical borehole flow rate measurements. Experiments using this approach, herein defined as the Bh-flow tracer test, have been performed by implementing three sequential steps: (1) single-hole flowmeter test, (2) cross-hole flowmeter test, and (3) tracer test. At the experimental site, core logging, pumping tests, and static water-level measurements were previously carried out to determine stratigraphy, fracture characteristics, and bulk hydraulic conductivity. Single-hole flowmeter testing makes it possible to detect the presence of vertical flows as well as inflow and outflow zones, whereas cross-hole flowmeter testing detects the presence of connections along sets of flow conduits or discontinuities intercepted by boreholes. Finally, the specific pathways and rates of groundwater flow through selected flowpaths are determined by tracer testing. We conclude that the combined use of single and cross-borehole flowmeter tests is fundamental to the formulation of the tracer test strategy and interpretation of the tracer test results. © 2014, National Ground Water Association.

  9. Accurate acoustic power measurement for low-intensity focused ultrasound using focal axial vibration velocity

    Science.gov (United States)

    Tao, Chenyang; Guo, Gepu; Ma, Qingyu; Tu, Juan; Zhang, Dong; Hu, Jimin

    2017-07-01

    Low-intensity focused ultrasound is a form of therapy that can have reversible acoustothermal effects on biological tissue, depending on the exposure parameters. The acoustic power (AP) should be chosen with caution for the sake of safety. To recover the energy of counteracted radial vibrations at the focal point, an accurate AP measurement method using the focal axial vibration velocity (FAVV) is proposed in explicit formulae and is demonstrated experimentally using a laser vibrometer. The experimental APs for two transducers agree well with theoretical calculations and numerical simulations, showing that AP is proportional to the square of the FAVV, with a fixed power gain determined by the physical parameters of the transducers. The favorable results suggest that the FAVV can be used as a valuable parameter for non-contact AP measurement, providing a new strategy for accurate power control for low-intensity focused ultrasound in biomedical engineering.

  10. Accurate measurement of the time delay in the response of the LIGO gravitational wave detectors

    OpenAIRE

    Aso, Yoichi; Goetz, Evan; Kalmus, Peter; Matone, Luca; Márka, Szabolcs; Myers, Joshua; O’Reilly, Brian; Savage, Rick; Schwinberg, Paul; Siemens, Xavier; Sigg, Daniel; Smith, Nicolas

    2009-01-01

    We present a method to precisely calibrate the time delay in a long baseline gravitational-wave interferometer. An accurate time stamp is crucial for data analysis of gravitational wave detectors, especially when performing coincidence and correlation analyses between multiple detectors. Our method uses an intensity-modulated radiation pressure force to actuate on the mirrors. The time delay is measured by comparing the phase of the signal at the actuation point with the phase of the recorded...

  11. Atom interferometry experiments with lithium. Accurate measurement of the electric polarizability

    International Nuclear Information System (INIS)

    Miffre, A.

    2005-06-01

    Atom interferometers are very sensitive tools to make precise measurements of physical quantities. This study presents a measurement of the static electric polarizability of lithium by atom interferometry. Our result, α = (24.33 ± 0.16)*10 -30 m 3 , improves by a factor 3 the most accurate measurements of this quantity. This work describes the tuning and the operation of a Mach-Zehnder atom interferometer in detail. The two interfering arms are separated by the elastic diffraction of the atomic wave by a laser standing wave, almost resonant with the first resonance transition of lithium atom. A set of experimental techniques, often complicated to implement, is necessary to build the experimental set-up. After a detailed study of the atom source (a supersonic beam of lithium seeded in argon), we present our experimental atom signals which exhibit a very high fringe visibility, up to 84.5 % for first order diffraction. A wide variety of signals has been observed by diffraction of the bosonic isotope at higher diffraction orders and by diffraction of the fermionic less abundant isotope. The quality of these signals is then used to do very accurate phase measurements. A first experiment investigates how the atom interferometer signals are modified by a magnetic field gradient. An absolute measurement of lithium atom electric polarizability is then achieved by applying a static electric field on one of the two interfering arms, separated by only 90 micrometers. The construction of such a capacitor, its alignment in the experimental set-up and its operation are fully detailed.We obtain a very accurate phase measurement of the induced Lo Surdo - Stark phase shift (0.07 % precision). For this first measurement, the final uncertainty on the electric polarizability of lithium is only 0.66 %, and is dominated by the uncertainty on the atom beam mean velocity, so that a further reduction of the uncertainty can be expected. (author)

  12. Accurate offline dispersion measurement of Petawatt-class chirped pulse amplification compressor and stretcher systems

    International Nuclear Information System (INIS)

    Haefner, C.; Crane, J.; Halpin, J.; Heebner, J.; Kanz, V.; Phan, H.; Nissen, J.; Shverdin, M.; Hackel, R.; Dawson, J.; Messerly, M.; Siders, C.W.

    2010-01-01

    Complete text of publication follows. The Advanced Radiographic Capability (ARC) on the National Ignition Facility (NIF) is designed to produce energetic x-rays in the range of 10-100 keV for backlighting NIF targets. ARC will convert 4 of the 192 NIF beamlines into 8 split beams, delivering laser pulses with adjustable pulse durations from 1 ps to 50 ps at the kilo-Joule level. Adjustable time delays between the 8 beams enable X-ray 'motion-picture' capture with tens-of-picosecond resolution during the critical phases of an ICF shot. The precise alignment of stretcher-compressor pairs in energetic chirped pulse amplification (CPA) systems is tedious and requires several iterations using advanced temporal diagnostics until the shortest pulse durations and highest peak intensities are achieved. For large, energetic Petawatt laser systems with beam sizes up to 40 cm, diffraction gratings in the compressor reach meter-scale size and are difficult to precisely align. We developed a group delay diagnostic which enables accurate, offline measurements of highly dispersive components such as stretchers or compressors with sub-picosecond accuracy. This diagnostic tool enables us to simply measure each dispersive component offline, and balance the dispersion in each beamline. Furthermore it allows exactly matching the dispersion of ARC's eight, independent four-grating compressors, which is critical for producing eight identical pulses. ARC utilizes a unique, folded compressor design for maximum compactness; two 5.5 m long vacuum vessels house 8 compressors with 91 cm x 45 cm multilayer, dielectric gratings. The group delay diagnostic utilizes the phase-shift technique for measuring the dispersion characteristics of each individual element, e.g. grating stretcher, chirped fiber Bragg grating, grating compressor, material dispersion, or an entire laser system. The system uses an amplitude modulated, highly-stable, single-frequency laser, which is scanned over the spectral

  13. The preliminary exploration of 64-slice volume computed tomography in the accurate measurement of pleural effusion

    International Nuclear Information System (INIS)

    Guo, Zhi-Jun; Lin, Qiang; Liu, Hai-Tao

    2013-01-01

    Background: Using computed tomography (CT) to rapidly and accurately quantify pleural effusion volume benefits medical and scientific research. However, the precise volume of pleural effusions still involves many challenges and currently does not have a recognized accurate measuring. Purpose: To explore the feasibility of using 64-slice CT volume-rendering technology to accurately measure pleural fluid volume and to then analyze the correlation between the volume of the free pleural effusion and the different diameters of the pleural effusion. Material and Methods: The 64-slice CT volume-rendering technique was used to measure and analyze three parts. First, the fluid volume of a self-made thoracic model was measured and compared with the actual injected volume. Second, the pleural effusion volume was measured before and after pleural fluid drainage in 25 patients, and the volume reduction was compared with the actual volume of the liquid extract. Finally, the free pleural effusion volume was measured in 26 patients to analyze the correlation between it and the diameter of the effusion, which was then used to calculate the regression equation. Results: After using the 64-slice CT volume-rendering technique to measure the fluid volume of the self-made thoracic model, the results were compared with the actual injection volume. No significant differences were found, P = 0.836. For the 25 patients with drained pleural effusions, the comparison of the reduction volume with the actual volume of the liquid extract revealed no significant differences, P = 0.989. The following linear regression equation was used to compare the pleural effusion volume (V) (measured by the CT volume-rendering technique) with the pleural effusion greatest depth (d): V = 158.16 X d - 116.01 (r = 0.91, P = 0.000). The following linear regression was used to compare the volume with the product of the pleural effusion diameters (l X h X d): V = 0.56 X (l X h X d) + 39.44 (r = 0.92, P = 0

  14. Accurate calibration of waveform data measured by the Plasma Wave Experiment on board the ARASE satellite

    Science.gov (United States)

    Kitahara, M.; Katoh, Y.; Hikishima, M.; Kasahara, Y.; Matsuda, S.; Kojima, H.; Ozaki, M.; Yagitani, S.

    2017-12-01

    The Plasma Wave Experiment (PWE) is installed on board the ARASE satellite to measure the electric field in the frequency range from DC to 10 MHz, and the magnetic field in the frequency range from a few Hz to 100 kHz using two dipole wire-probe antennas (WPT) and three magnetic search coils (MSC), respectively. In particular, the Waveform Capture (WFC), one of the receivers of the PWE, can detect electromagnetic field waveform in the frequency range from a few Hz to 20 kHz. The Software-type Wave Particle Interaction Analyzer (S-WPIA) is installed on the ARASE satellite to measure the energy exchange between plasma waves and particles. Since S-WPIA uses the waveform data measured by WFC to calculate the relative phase angle between the wave magnetic field and velocity of energetic electrons, the high-accuracy is required to calibration of both amplitude and phase of the waveform data. Generally, the calibration procedure of the signal passed through a receiver consists of three steps; the transformation into spectra, the calibration by the transfer function of a receiver, and the inverse transformation of the calibrated spectra into the time domain. Practically, in order to reduce the side robe effect, a raw data is filtered by a window function in the time domain before applying Fourier transform. However, for the case that a first order differential coefficient of the phase transfer function of the system is not negligible, the phase of the window function convoluted into the calibrated spectra is shifted differently at each frequency, resulting in a discontinuity in the time domain of the calibrated waveform data. To eliminate the effect of the phase shift of a window function, we suggest several methods to calibrate a waveform data accurately and carry out simulations assuming simple sinusoidal waves as an input signal and using transfer functions of WPT, MSC, and WFC obtained in pre-flight tests. In consequence, we conclude that the following two methods can

  15. Considerations for accurate gene expression measurement by reverse transcription quantitative PCR when analysing clinical samples.

    Science.gov (United States)

    Sanders, Rebecca; Mason, Deborah J; Foy, Carole A; Huggett, Jim F

    2014-10-01

    Reverse transcription quantitative PCR is an established, simple and effective method for RNA measurement. However, technical standardisation challenges combined with frequent insufficient experimental detail render replication of many published findings challenging. Consequently, without adequate consideration of experimental standardisation, such findings may be sufficient for a given publication but cannot be translated to wider clinical application. This article builds on earlier standardisation work and the MIQE guidelines, discussing processes that need consideration for accurate, reproducible analysis when dealing with patient samples. By applying considerations common to the science of measurement (metrology), one can maximise the impact of gene expression studies, increasing the likelihood of their translation to clinical tools.

  16. Fast and accurate measurement of on-axis gain and on-axis polarization at a finite distance

    DEFF Research Database (Denmark)

    Pivnenko, S.; Breinbjerg, O.

    2013-01-01

    In this paper, a technique for fast and accurate measurement of on-axis gain and on-axis polarization characteristics of antennas, such as Standard Gain Horns, compact range feed horns, and near-field probes, is described. The proposed gain determination procedure is a modification of the far......-field substitution technique in which the measurement distance is defined between the phase centres of the antennas. The location of the phase centre of the antenna under test (AUT) is found from a quick pattern measurement consisting of only four cuts including the main and diagonal planes. Additionally, in order...... to reduce the amount of measurement data and thus measurement time, the phase centre location is found on a sparse frequency grid and the values in the intermediate points are found by interpolation. The antenna polarization is determined from the amplitude/phase frequency sweeps with two orthogonal AUT...

  17. Test limits using correlated measurements

    NARCIS (Netherlands)

    Albers, Willem/Wim; Arts, G.R.J.; Kallenberg, W.C.M.

    1998-01-01

    In the standard model for inspection of manufactured parts measurements of the characteristic of interest are subject to, typically small, measurement errors. This leads to test limits which are slightly more strict than the corresponding specification limits. Quite often, however, such direct

  18. Infrared Thermometer: an accurate tool for temperature measurement during renal surgery

    Directory of Open Access Journals (Sweden)

    Giovanni Scala Marchini

    2013-07-01

    Full Text Available Purpose To evaluate infrared thermometer (IRT accuracy compared to standard digital thermometer in measuring kidney temperature during arterial clamping with and without renal cooling. Materials and Methods 20 pigs weighting 20Kg underwent selective right renal arterial clamping, 10 with (Group 1 - Cold Ischemia with ice slush and 10 without renal cooling (Group 2 - Warm Ischemia. Arterial clamping was performed without venous clamping. Renal temperature was serially measured following clamping of the main renal artery with the IRT and a digital contact thermometer (DT: immediate after clamping (T0, after 2 (T2, 5 (T5 and 10 minutes (T10. Temperature values were expressed in mean, standard deviation and range for each thermometer. We used the T student test to compare means and considered p < 0.05 to be statistically significant. Results In Group 1, mean DT surface temperature decrease was 12.6 ± 4.1°C (5-19°C while deep DT temperature decrease was 15.8 ± 1.5°C (15-18°C. For the IRT, mean temperature decrease was 9.1 ± 3.8°C (3-14°C. There was no statistically significant difference between thermometers. In Group 2, surface temperature decrease for DT was 2.7 ± 1.8°C (0-4°C and mean deep temperature decrease was 0.5 ± 1.0°C (0-3°C. For IRT, mean temperature decrease was 3.1 ± 1.9°C (0-6°C. No statistically significant difference between thermometers was found at any time point. conclusions IRT proved to be an accurate non-invasive precise device for renal temperature monitoring during kidney surgery. External ice slush cooling confirmed to be fast and effective at cooling the pig model. IRT = Infrared thermometer DT = Digital contact thermometer D:S = Distance-to-spot ratio

  19. Conformance Testing: Measurement Decision Rules

    Science.gov (United States)

    Mimbs, Scott M.

    2010-01-01

    The goal of a Quality Management System (QMS) as specified in ISO 9001 and AS9100 is to provide assurance to the customer that end products meet specifications. Measuring devices, often called measuring and test equipment (MTE), are used to provide the evidence of product conformity to specified requirements. Unfortunately, processes that employ MTE can become a weak link to the overall QMS if proper attention is not given to the measurement process design, capability, and implementation. Documented "decision rules" establish the requirements to ensure measurement processes provide the measurement data that supports the needs of the QMS. Measurement data are used to make the decisions that impact all areas of technology. Whether measurements support research, design, production, or maintenance, ensuring the data supports the decision is crucial. Measurement data quality can be critical to the resulting consequences of measurement-based decisions. Historically, most industries required simplistic, one-size-fits-all decision rules for measurements. One-size-fits-all rules in some cases are not rigorous enough to provide adequate measurement results, while in other cases are overly conservative and too costly to implement. Ideally, decision rules should be rigorous enough to match the criticality of the parameter being measured, while being flexible enough to be cost effective. The goal of a decision rule is to ensure that measurement processes provide data with a sufficient level of quality to support the decisions being made - no more, no less. This paper discusses the basic concepts of providing measurement-based evidence that end products meet specifications. Although relevant to all measurement-based conformance tests, the target audience is the MTE end-user, which is anyone using MTE other than calibration service providers. Topics include measurement fundamentals, the associated decision risks, verifying conformance to specifications, and basic measurement

  20. Rapid yet accurate measurement of mass diffusion coefficients by phase shifting interferometer

    CERN Document Server

    Guo Zhi Xiong; Komiya, A

    1999-01-01

    The technique of using a phase-shifting interferometer is applied to the study of diffusion in transparent liquid mixtures. A quick method is proposed for determining the diffusion coefficient from the measurements of the location of fringes on a grey level picture. The measurement time is very short (within 100 s) and a very small transient diffusion field can be observed and recorded accurately with a rate of 30 frames per second. The measurement can be completed using less than 0.12 cc of solutions. The influence of gravity on the measurement of the diffusion coefficient is eliminated in the present method. Results on NaCl-water diffusion systems are presented and compared with the reference data. (author)

  1. Measuring physical inactivity: do current measures provide an accurate view of "sedentary" video game time?

    Science.gov (United States)

    Fullerton, Simon; Taylor, Anne W; Dal Grande, Eleonora; Berry, Narelle

    2014-01-01

    Measures of screen time are often used to assess sedentary behaviour. Participation in activity-based video games (exergames) can contribute to estimates of screen time, as current practices of measuring it do not consider the growing evidence that playing exergames can provide light to moderate levels of physical activity. This study aimed to determine what proportion of time spent playing video games was actually spent playing exergames. Data were collected via a cross-sectional telephone survey in South Australia. Participants aged 18 years and above (n = 2026) were asked about their video game habits, as well as demographic and socioeconomic factors. In cases where children were in the household, the video game habits of a randomly selected child were also questioned. Overall, 31.3% of adults and 79.9% of children spend at least some time playing video games. Of these, 24.1% of adults and 42.1% of children play exergames, with these types of games accounting for a third of all time that adults spend playing video games and nearly 20% of children's video game time. A substantial proportion of time that would usually be classified as "sedentary" may actually be spent participating in light to moderate physical activity.

  2. Particle Image Velocimetry Measurements in Anatomically-Accurate Models of the Mammalian Nasal Cavity

    Science.gov (United States)

    Rumple, C.; Richter, J.; Craven, B. A.; Krane, M.

    2012-11-01

    A summary of the research being carried out by our multidisciplinary team to better understand the form and function of the nose in different mammalian species that include humans, carnivores, ungulates, rodents, and marine animals will be presented. The mammalian nose houses a convoluted airway labyrinth, where two hallmark features of mammals occur, endothermy and olfaction. Because of the complexity of the nasal cavity, the anatomy and function of these upper airways remain poorly understood in most mammals. However, recent advances in high-resolution medical imaging, computational modeling, and experimental flow measurement techniques are now permitting the study of airflow and respiratory and olfactory transport phenomena in anatomically-accurate reconstructions of the nasal cavity. Here, we focus on efforts to manufacture transparent, anatomically-accurate models for stereo particle image velocimetry (SPIV) measurements of nasal airflow. Challenges in the design and manufacture of index-matched anatomical models are addressed and preliminary SPIV measurements are presented. Such measurements will constitute a validation database for concurrent computational fluid dynamics (CFD) simulations of mammalian respiration and olfaction. Supported by the National Science Foundation.

  3. Spontaneous fluctuation indices of the cardiovagal baroreflex accurately measure the baroreflex sensitivity at the operating point during upright tilt.

    Science.gov (United States)

    Schwartz, Christopher E; Medow, Marvin S; Messer, Zachary; Stewart, Julian M

    2013-06-15

    Spontaneous fluctuation indices of cardiovagal baroreflex have been suggested to be inaccurate measures of baroreflex function during orthostatic stress compared with alternate open-loop methods (e.g. neck pressure/suction, modified Oxford method). We therefore tested the hypothesis that spontaneous fluctuation measurements accurately reflect local baroreflex gain (slope) at the operating point measured by the modified Oxford method, and that apparent differences between these two techniques during orthostasis can be explained by a resetting of the baroreflex function curve. We computed the sigmoidal baroreflex function curves supine and during 70° tilt in 12 young, healthy individuals. With the use of the modified Oxford method, slopes (gains) of supine and upright curves were computed at their maxima (Gmax) and operating points. These were compared with measurements of spontaneous indices in both positions. Supine spontaneous analyses of operating point slope were similar to calculated Gmax of the modified Oxford curve. In contrast, upright operating point was distant from the centering point of the reset curve and fell on the nonlinear portion of the curve. Whereas spontaneous fluctuation measurements were commensurate with the calculated slope of the upright modified Oxford curve at the operating point, they were significantly lower than Gmax. In conclusion, spontaneous measurements of cardiovagal baroreflex function accurately estimate the slope near operating points in both supine and upright position.

  4. Combining MFD and PIE for accurate single-pair Förster resonance energy transfer measurements.

    Science.gov (United States)

    Kudryavtsev, Volodymyr; Sikor, Martin; Kalinin, Stanislav; Mokranjac, Dejana; Seidel, Claus A M; Lamb, Don C

    2012-03-01

    Single-pair Förster resonance energy transfer (spFRET) experiments using single-molecule burst analysis on a confocal microscope are an ideal tool to measure inter- and intramolecular distances and dynamics on the nanoscale. Different techniques have been developed to maximize the amount of information available in spFRET burst analysis experiments. Multiparameter fluorescence detection (MFD) is used to monitor a variety of fluorescence parameters simultaneously and pulsed interleaved excitation (PIE) employs direct excitation of the acceptor to probe its presence and photoactivity. To calculate accurate FRET efficiencies from spFRET experiments with MFD or PIE, several calibration measurements are usually required. Herein, we demonstrate that by combining MFD with PIE information regarding all calibration factors as well as an accurate determination of spFRET histograms can be performed in a single measurement. In addition, the quality of overlap of the different detection volumes as well as the detection of acceptor photophysics can be investigated with MFD-PIE. Bursts containing acceptor photobleaching can be identified and excluded from further investigation while bursts that contain FRET dynamics are unaffected by this analysis. We have employed MFD-PIE to accurately analyze the effects of nucleotides and substrate on the interdomain separation in DnaK, the major bacterial heat shock protein 70 (Hsp70). The interdomain distance increases from 47 Å in the ATP-bound state to 84 Å in the ADP-bound state and slightly contracts to 77 Å when a substrate is bound. This is in contrast to what was observed for the mitochondrial member of the Hsp70s, Ssc1, supporting the notion of evolutionary specialization of Hsp70s for different cellular functions in different organisms and cell organelles. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Accurate mass measurements of very short-lived nuclei. Prerequisites for high-accuracy investigations of superallowed β-decays

    International Nuclear Information System (INIS)

    Herfurth, F.; Kellerbauer, A.; Sauvan, E.; Ames, F.; Engels, O.; Audi, G.; Lunney, D.; Beck, D.; Blaum, K.; Kluge, H.J.; Scheidenberger, C.; Sikler, G.; Weber, C.; Bollen, G.; Schwarz, S.; Moore, R.B.; Oinonen, M.

    2002-01-01

    Mass measurements of 34 Ar, 73-78 Kr, and 74,76 Rb were performed with the Penning-trap mass spectrometer ISOLTRAP. Very accurate Q EC -values are needed for the investigations of the Ft-value of 0 + → 0 + nuclear β-decays used to test the standard model predictions for weak interactions. The necessary accuracy on the Q EC -value requires the mass of mother and daughter nuclei to be measured with δm/m ≤ 3 . 10 -8 . For most of the measured nuclides presented here this has been reached. The 34 Ar mass has been measured with a relative accuracy of 1.1 .10 -8 . The Q EC -value of the 34 Ar 0 + → 0 + decay can now be determined with an uncertainty of about 0.01%. Furthermore, 74 Rb is the shortest-lived nuclide ever investigated in a Penning trap. (orig.)

  6. Development of an improved Kelvin probe force microscope for accurate local potential measurements on biased electronic devices.

    Science.gov (United States)

    Bercu, N B; Giraudet, L; Simonetti, O; Molinari, M

    2017-09-01

    An improved setup for accurate near-field surface potential measurements and characterisation of biased electronic devices using the Kelvin Probe method has been developed. Using an external voltage source synchronised with the raster-scan of the KPFM-AM, this setup allows to avoid potential measurement errors of the conventional Kelvin Probe Force Microscopy in the case of in situ measurements on biased electronic devices. This improved KPFM-AM setup has been tested on silicon-based devices and organic semiconductor-based devices such as organic field effect transistors (OFETs), showing differences up to 25% compared to the standard KPFM-AM lift-mode measurement method. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  7. A Flexible Fringe Projection Vision System with Extended Mathematical Model for Accurate Three-Dimensional Measurement

    Directory of Open Access Journals (Sweden)

    Suzhi Xiao

    2016-04-01

    Full Text Available In order to acquire an accurate three-dimensional (3D measurement, the traditional fringe projection technique applies complex and laborious procedures to compensate for the errors that exist in the vision system. However, the error sources in the vision system are very complex, such as lens distortion, lens defocus, and fringe pattern nonsinusoidality. Some errors cannot even be explained or rendered with clear expressions and are difficult to compensate directly as a result. In this paper, an approach is proposed that avoids the complex and laborious compensation procedure for error sources but still promises accurate 3D measurement. It is realized by the mathematical model extension technique. The parameters of the extended mathematical model for the ’phase to 3D coordinates transformation’ are derived using the least-squares parameter estimation algorithm. In addition, a phase-coding method based on a frequency analysis is proposed for the absolute phase map retrieval to spatially isolated objects. The results demonstrate the validity and the accuracy of the proposed flexible fringe projection vision system on spatially continuous and discontinuous objects for 3D measurement.

  8. A Flexible Fringe Projection Vision System with Extended Mathematical Model for Accurate Three-Dimensional Measurement.

    Science.gov (United States)

    Xiao, Suzhi; Tao, Wei; Zhao, Hui

    2016-04-28

    In order to acquire an accurate three-dimensional (3D) measurement, the traditional fringe projection technique applies complex and laborious procedures to compensate for the errors that exist in the vision system. However, the error sources in the vision system are very complex, such as lens distortion, lens defocus, and fringe pattern nonsinusoidality. Some errors cannot even be explained or rendered with clear expressions and are difficult to compensate directly as a result. In this paper, an approach is proposed that avoids the complex and laborious compensation procedure for error sources but still promises accurate 3D measurement. It is realized by the mathematical model extension technique. The parameters of the extended mathematical model for the 'phase to 3D coordinates transformation' are derived using the least-squares parameter estimation algorithm. In addition, a phase-coding method based on a frequency analysis is proposed for the absolute phase map retrieval to spatially isolated objects. The results demonstrate the validity and the accuracy of the proposed flexible fringe projection vision system on spatially continuous and discontinuous objects for 3D measurement.

  9. Geometric optimisation of an accurate cosine correcting optic fibre coupler for solar spectral measurement

    Science.gov (United States)

    Cahuantzi, Roberto; Buckley, Alastair

    2017-09-01

    Making accurate and reliable measurements of solar irradiance is important for understanding performance in the photovoltaic energy sector. In this paper, we present design details and performance of a number of fibre optic couplers for use in irradiance measurement systems employing remote light sensors applicable for either spectrally resolved or broadband measurement. The angular and spectral characteristics of different coupler designs are characterised and compared with existing state-of-the-art commercial technology. The new coupler designs are fabricated from polytetrafluorethylene (PTFE) rods and operate through forward scattering of incident sunlight on the front surfaces of the structure into an optic fibre located in a cavity to the rear of the structure. The PTFE couplers exhibit up to 4.8% variation in scattered transmission intensity between 425 nm and 700 nm and show minimal specular reflection, making the designs accurate and reliable over the visible region. Through careful geometric optimization near perfect cosine dependence on the angular response of the coupler can be achieved. The PTFE designs represent a significant improvement over the state of the art with less than 0.01% error compared with ideal cosine response for angles of incidence up to 50°.

  10. Comparison of thermistor linearization techniques for accurate temperature measurement in phase change materials

    Energy Technology Data Exchange (ETDEWEB)

    Stankovic, S B; Kyriacou, P A, E-mail: p.kyriacou@city.ac.uk [School of Engineering and Mathematical Sciences, City University London, Northampton Square, London EC1V 0HB (United Kingdom)

    2011-08-17

    Alternate energy technologies are developing rapidly in the recent years. A significant part of this trend is the development of different phase change materials (PCMs). Proper utilization of PCMs requires accurate thermal characterization. There are several methodologies used in this field. This paper stresses the importance of accurate temperature measurements during the implementation of T-history method. Since the temperature sensor size is also important thermistors have been selected as the sensing modality. Two thermistor linearization techniques, one based on Wheatstone bridge and the other based on simple serial-parallel resistor connection, are compared in terms of achievable temperature accuracy through consideration of both, nonlinearity and self-heating errors. Proper calibration was performed before T-history measurement of RT21 (RUBITHERM (registered) GmbH) PCM. Measurement results suggest that the utilization of serial-parallel resistor connection gives better accuracy (less than {+-}0.1 deg. C) in comparison with the Wheatstone bridge based configuration (up to {+-}1.5 deg. C).

  11. Accurate Measurements of the Dielectric Constant of Seawater at L Band

    Science.gov (United States)

    Lang, Roger; Zhou, Yiwen; Utku, Cuneyt; Le Vine, David

    2016-01-01

    This paper describes measurements of the dielectric constant of seawater at a frequency of 1.413 GHz, the center of the protected band (i.e., passive use only) used in the measurement of sea surface salinity from space. The objective of the measurements is to accurately determine the complex dielectric constant of seawater as a function of salinity and temperature. A resonant cylindrical microwave cavity in transmission mode has been employed to make the measurements. The measurements are made using standard seawater at salinities of 30, 33, 35, and 38 practical salinity units over a range of temperatures from 0 degree C to 35 degree C in 5 degree C intervals. Repeated measurements have been made at each temperature and salinity. Mean values and standard deviations are then computed. The total error budget indicates that the real and imaginary parts of the dielectric constant have a combined standard uncertainty of about 0.3 over the range of salinities and temperatures considered. The measurements are compared with the dielectric constants obtained from the model functions of Klein and Swift and those of Meissner and Wentz. The biggest differences occur at low and high temperatures.

  12. Accurate Estimation of Low Fundamental Frequencies from Real-Valued Measurements

    DEFF Research Database (Denmark)

    Christensen, Mads Græsbøll

    2013-01-01

    In this paper, the difficult problem of estimating low fundamental frequencies from real-valued measurements is addressed. The methods commonly employed do not take the phenomena encountered in this scenario into account and thus fail to deliver accurate estimates. The reason for this is that the......In this paper, the difficult problem of estimating low fundamental frequencies from real-valued measurements is addressed. The methods commonly employed do not take the phenomena encountered in this scenario into account and thus fail to deliver accurate estimates. The reason...... for this is that they employ asymptotic approximations that are violated when the harmonics are not well-separated in frequency, something that happens when the observed signal is real-valued and the fundamental frequency is low. To mitigate this, we analyze the problem and present some exact fundamental frequency estimators...... that are aimed at solving this problem. These esti- mators are based on the principles of nonlinear least-squares, harmonic fitting, optimal filtering, subspace orthogonality, and shift-invariance, and they all reduce to already published methods for a high number of observations. In experiments, the methods...

  13. Accurate heat transfer measurements using thermochromic liquid crystal. Part 1: Calibration and characteristics of crystals

    International Nuclear Information System (INIS)

    Kakade, V.U.; Lock, G.D.; Wilson, M.; Owen, J.M.; Mayhew, J.E.

    2009-01-01

    Encapsulated thermochromic liquid crystal (TLC) can accurately measure surface temperature in a variety of heat transfer and fluid flow experiments. Narrow-band TLC, where the colour changes over a temperature range of ∼1 deg. C, can be used to determine surface temperature within an uncertainty of 0.1 deg. C. Wide-band TLC, typically active over 5-20 deg. C, allow the possibility of mapping surface temperature distributions. In part 1 of this two-part paper, an extensive set of calibrations for narrow-band and wide-band TLC is reported. This generic study provides insight into the importance and influence of the various factors governing the colour-temperature relationship. These governing effects include the variation in optical path, the spectrum of the illumination source, the lighting and viewing angles, the differences between cooling or heating cycles (hysteresis), the variation with the number of heating or cooling cycles (aging) and how this varies with TLC film thickness. Two narrow-band crystals are also specifically calibrated for application to experiments on a transparent disc rotating at high speed (∼5000 rpm). Part 2 of this paper describes how these accurately-calibrated crystals were used to measure the transient surface temperature on, and heat transfer to, a rotating disc.

  14. Apparatus for accurate density measurements of fluids based on a magnetic suspension balance

    Science.gov (United States)

    Gong, Maoqiong; Li, Huiya; Guo, Hao; Dong, Xueqiang; Wu, J. F.

    2012-06-01

    A new apparatus for accurate pressure, density and temperature (p, ρ, T) measurements over wide ranges of (p, ρ, T) (90 K to 290 K; 0 MPa to 3 MPa; 0 kg/m3 to 2000 kg/m3) is described. This apparatus is based on a magnetic suspension balance which applies the Archimedes' buoyancy principle. In order to verify the new apparatus, comprehensive (p, ρ, T) measurements on pure nitrogen were carried out. The maximum relative standard uncertainty is 0.09% in density. The maximum standard uncertainty in temperature is 5 mK, and that in pressure is 250 Pa for 1.5 MPa and 390 Pa for 3MPa full scale range respectively. The experimental data were compared with selected literature data and good agreements were found.

  15. Technical developments for accurate determination of amount of samples used for TOF measurements

    Directory of Open Access Journals (Sweden)

    Terada Kazushi

    2017-01-01

    Full Text Available Activity determination of 241,243Am samples has been performed with two separate methods of calorimetry and gamma-ray spectroscopy. Decay heat measurements of the samples were carried out by using a calorimeter, and activities of the samples were accurately determined with uncertainties less than 0.45%. The primary source of uncertainty in the calorimetric method is the accuracy of available half-life data. Gamma-ray detection efficiencies of a HPGe detector were determined with uncertainties of 1.5% by combining measured efficiencies and Monte Carlo simulation. Activities of the samples were determined with uncertainties less than 2.0% by gamma-ray spectroscopy and were concordant with those of the calorimetry.

  16. Highly accurate thickness measurement of multi-layered automotive paints using terahertz technology

    Science.gov (United States)

    Krimi, Soufiene; Klier, Jens; Jonuscheit, Joachim; von Freymann, Georg; Urbansky, Ralph; Beigang, René

    2016-07-01

    In this contribution, we present a highly accurate approach for thickness measurements of multi-layered automotive paints using terahertz time domain spectroscopy in reflection geometry. The proposed method combines the benefits of a model-based material parameters extraction method to calibrate the paint coatings, a generalized Rouard's method to simulate the terahertz radiation behavior within arbitrary thin films, and the robustness of a powerful evolutionary optimization algorithm to increase the sensitivity of the minimum thickness measurement limit. Within the framework of this work, a self-calibration model is introduced, which takes into consideration the real industrial challenges such as the effect of wet-on-wet spray in the painting process.

  17. Highly accurate thickness measurement of multi-layered automotive paints using terahertz technology

    International Nuclear Information System (INIS)

    Krimi, Soufiene; Beigang, René; Klier, Jens; Jonuscheit, Joachim; Freymann, Georg von; Urbansky, Ralph

    2016-01-01

    In this contribution, we present a highly accurate approach for thickness measurements of multi-layered automotive paints using terahertz time domain spectroscopy in reflection geometry. The proposed method combines the benefits of a model-based material parameters extraction method to calibrate the paint coatings, a generalized Rouard's method to simulate the terahertz radiation behavior within arbitrary thin films, and the robustness of a powerful evolutionary optimization algorithm to increase the sensitivity of the minimum thickness measurement limit. Within the framework of this work, a self-calibration model is introduced, which takes into consideration the real industrial challenges such as the effect of wet-on-wet spray in the painting process.

  18. Modified AC Wheatstone Bridge Network for Accurate Measurement of Pressure Using Strain Gauge Type Pressure Sensor

    Directory of Open Access Journals (Sweden)

    Subrata CHATTOPADHYAY

    2012-01-01

    Full Text Available In order to achieve high quality of products at lesser cost, accurate measurement of different process variables is of vital importance in any industry. There are different well-established techniques of measurement and control instrumentations of these variables. In the resistive transducer like strain gauge, the small resistance generally changes linearly with a process variable like pressure but their measurement by usual AC Wheatstone bridge circuit may suffer from errors due to the effect of stray capacitance between bridge nodal points and ground and stray inductance on the strain gauge grid respectively. Though the conventional Wagner-Earth technique may be used to reduced the error but not suitable for continuous measurement. In the present paper, a modified operational amplifier based AC Wheatstone bridge measurement technique has been proposed in which the effect of stray capacitance and inductance is minimized. This bridge performance has been studied experimentally with the strain gauge type pressure transducer. The linear characteristics over a wide range of pressure with good repeatability, linearity and variable sensitivity have been described.

  19. Testing substellar models with dynamical mass measurements

    Directory of Open Access Journals (Sweden)

    Liu M.C.

    2011-07-01

    Full Text Available We have been using Keck laser guide star adaptive optics to monitor the orbits of ultracool binaries, providing dynamical masses at lower luminosities and temperatures than previously available and enabling strong tests of theoretical models. We have identified three specific problems with theory: (1 We find that model color–magnitude diagrams cannot be reliably used to infer masses as they do not accurately reproduce the colors of ultracool dwarfs of known mass. (2 Effective temperatures inferred from evolutionary model radii are typically inconsistent with temperatures derived from fitting atmospheric models to observed spectra by 100–300 K. (3 For the only known pair of field brown dwarfs with a precise mass (3% and age determination (≈25%, the measured luminosities are ~2–3× higher than predicted by model cooling rates (i.e., masses inferred from Lbol and age are 20–30% larger than measured. To make progress in understanding the observed discrepancies, more mass measurements spanning a wide range of luminosity, temperature, and age are needed, along with more accurate age determinations (e.g., via asteroseismology for primary stars with brown dwarf binary companions. Also, resolved optical and infrared spectroscopy are needed to measure lithium depletion and to characterize the atmospheres of binary components in order to better assess model deficiencies.

  20. Smart density: A more accurate method of measuring rural residential density for health-related research.

    Science.gov (United States)

    Owens, Peter M; Titus-Ernstoff, Linda; Gibson, Lucinda; Beach, Michael L; Beauregard, Sandy; Dalton, Madeline A

    2010-02-12

    Studies involving the built environment have typically relied on US Census data to measure residential density. However, census geographic units are often unsuited to health-related research, especially in rural areas where development is clustered and discontinuous. We evaluated the accuracy of both standard census methods and alternative GIS-based methods to measure rural density. We compared residential density (units/acre) in 335 Vermont school neighborhoods using conventional census geographic units (tract, block group and block) with two GIS buffer measures: a 1-kilometer (km) circle around the school and a 1-km circle intersected with a 100-meter (m) road-network buffer. The accuracy of each method was validated against the actual residential density for each neighborhood based on the Vermont e911 database, which provides an exact geo-location for all residential structures in the state. Standard census measures underestimate residential density in rural areas. In addition, the degree of error is inconsistent so even the relative rank of neighborhood densities varies across census measures. Census measures explain only 61% to 66% of the variation in actual residential density. In contrast, GIS buffer measures explain approximately 90% of the variation. Combining a 1-km circle with a road-network buffer provides the closest approximation of actual residential density. Residential density based on census units can mask clusters of development in rural areas and distort associations between residential density and health-related behaviors and outcomes. GIS-defined buffers, including a 1-km circle and a road-network buffer, can be used in conjunction with census data to obtain a more accurate measure of residential density.

  1. Smart density: a more accurate method of measuring rural residential density for health-related research

    Directory of Open Access Journals (Sweden)

    Gibson Lucinda

    2010-02-01

    Full Text Available Abstract Background Studies involving the built environment have typically relied on US Census data to measure residential density. However, census geographic units are often unsuited to health-related research, especially in rural areas where development is clustered and discontinuous. Objective We evaluated the accuracy of both standard census methods and alternative GIS-based methods to measure rural density. Methods We compared residential density (units/acre in 335 Vermont school neighborhoods using conventional census geographic units (tract, block group and block with two GIS buffer measures: a 1-kilometer (km circle around the school and a 1-km circle intersected with a 100-meter (m road-network buffer. The accuracy of each method was validated against the actual residential density for each neighborhood based on the Vermont e911 database, which provides an exact geo-location for all residential structures in the state. Results Standard census measures underestimate residential density in rural areas. In addition, the degree of error is inconsistent so even the relative rank of neighborhood densities varies across census measures. Census measures explain only 61% to 66% of the variation in actual residential density. In contrast, GIS buffer measures explain approximately 90% of the variation. Combining a 1-km circle with a road-network buffer provides the closest approximation of actual residential density. Conclusion Residential density based on census units can mask clusters of development in rural areas and distort associations between residential density and health-related behaviors and outcomes. GIS-defined buffers, including a 1-km circle and a road-network buffer, can be used in conjunction with census data to obtain a more accurate measure of residential density.

  2. Accurate and automatic extrinsic calibration method for blade measurement system integrated by different optical sensors

    Science.gov (United States)

    He, Wantao; Li, Zhongwei; Zhong, Kai; Shi, Yusheng; Zhao, Can; Cheng, Xu

    2014-11-01

    Fast and precise 3D inspection system is in great demand in modern manufacturing processes. At present, the available sensors have their own pros and cons, and hardly exist an omnipotent sensor to handle the complex inspection task in an accurate and effective way. The prevailing solution is integrating multiple sensors and taking advantages of their strengths. For obtaining a holistic 3D profile, the data from different sensors should be registrated into a coherent coordinate system. However, some complex shape objects own thin wall feather such as blades, the ICP registration method would become unstable. Therefore, it is very important to calibrate the extrinsic parameters of each sensor in the integrated measurement system. This paper proposed an accurate and automatic extrinsic parameter calibration method for blade measurement system integrated by different optical sensors. In this system, fringe projection sensor (FPS) and conoscopic holography sensor (CHS) is integrated into a multi-axis motion platform, and the sensors can be optimally move to any desired position at the object's surface. In order to simple the calibration process, a special calibration artifact is designed according to the characteristics of the two sensors. An automatic registration procedure based on correlation and segmentation is used to realize the artifact datasets obtaining by FPS and CHS rough alignment without any manual operation and data pro-processing, and then the Generalized Gauss-Markoff model is used to estimate the optimization transformation parameters. The experiments show the measurement result of a blade, where several sampled patches are merged into one point cloud, and it verifies the performance of the proposed method.

  3. An accurately controllable imitative stress corrosion cracking for electromagnetic nondestructive testing and evaluations

    International Nuclear Information System (INIS)

    Yusa, Noritaka; Uchimoto, Tetsuya; Takagi, Toshiyuki; Hashizume, Hidetoshi

    2012-01-01

    Highlights: ► We propose a method to simulate stress corrosion cracking. ► The method offers nondestructive signals similar to those of actual cracking. ► Visual and eddy current examinations validate the method. - Abstract: This study proposes a simple and cost-effective approach to fabricate an artificial flaw that is identical to stress corrosion cracking especially from the viewpoint of electromagnetic nondestructive evaluations. The key idea of the approach is to embed a partially-bonded region inside a material by bonding together surfaces that have grooves. The region is regarded as an area of uniform non-zero conductivity from an electromagnetic nondestructive point of view, and thus simulates the characteristics of stress corrosion cracking. Since the grooves are introduced using electro-discharge machining, one can control the profile of the imitative stress corrosion cracking accurately. After numerical simulation to evaluate the spatial resolution of conventional eddy current testing, six specimens made of type 316L austenitic stainless steel were fabricated on the basis of the results of the simulations. Visual and eddy current examinations were carried out to demonstrate that the artificial flaws well simulated the characteristics of actual stress corrosion cracking. Subsequent destructive test confirmed that the bonding did not change the depth profiles of the artificial flaw.

  4. Accurate label-free reaction kinetics determination using initial rate heat measurements

    Science.gov (United States)

    Ebrahimi, Kourosh Honarmand; Hagedoorn, Peter-Leon; Jacobs, Denise; Hagen, Wilfred R.

    2015-01-01

    Accurate label-free methods or assays to obtain the initial reaction rates have significant importance in fundamental studies of enzymes and in application-oriented high throughput screening of enzyme activity. Here we introduce a label-free approach for obtaining initial rates of enzyme activity from heat measurements, which we name initial rate calorimetry (IrCal). This approach is based on our new finding that the data recorded by isothermal titration calorimetry for the early stages of a reaction, which have been widely ignored, are correlated to the initial rates. Application of the IrCal approach to various enzymes led to accurate enzyme kinetics parameters as compared to spectroscopic methods and enabled enzyme kinetic studies with natural substrate, e.g. proteases with protein substrates. Because heat is a label-free property of almost all reactions, the IrCal approach holds promise in fundamental studies of various enzymes and in use of calorimetry for high throughput screening of enzyme activity. PMID:26574737

  5. Accurate measurement of mitochondrial DNA deletion level and copy number differences in human skeletal muscle.

    Directory of Open Access Journals (Sweden)

    John P Grady

    Full Text Available Accurate and reliable quantification of the abundance of mitochondrial DNA (mtDNA molecules, both wild-type and those harbouring pathogenic mutations, is important not only for understanding the progression of mtDNA disease but also for evaluating novel therapeutic approaches. A clear understanding of the sensitivity of mtDNA measurement assays under different experimental conditions is therefore critical, however it is routinely lacking for most published mtDNA quantification assays. Here, we comprehensively assess the variability of two quantitative Taqman real-time PCR assays, a widely-applied MT-ND1/MT-ND4 multiplex mtDNA deletion assay and a recently developed MT-ND1/B2M singleplex mtDNA copy number assay, across a range of DNA concentrations and mtDNA deletion/copy number levels. Uniquely, we provide a specific guide detailing necessary numbers of sample and real-time PCR plate replicates for accurately and consistently determining a given difference in mtDNA deletion levels and copy number in homogenate skeletal muscle DNA.

  6. An accurate measurement of the Rosemount 1152 differential pressure cell response time

    International Nuclear Information System (INIS)

    Hinds, H.W.; Gao, Y.; Tonner, P.D.

    1997-01-01

    The primary heat-transport (PHT) system of a CANDU reactor includes four quadrants of reactor coolant channels, each fed from its own inlet header through a large number of inlet feeders. As part of the safety shutdown system 1 (SDS1) and Reactor Regulating System (RRS) of CANDU reactors, differential-pressure (DP) cells are used to monitor the reactor coolant flows in each quadrant and to register changes with a prescribed response time. This paper describes an accurate in-situ measurement of the response time of two Rosemount 1152 DPA22PB DP cells, one from SDS1 and one from an RRS fully instrumented channel. The response time measurement was done using high-frequency pressure-measurement devises temporarily installed on the high- and low-pressure sides of the DP cells. The results suggest that the actual time constant of the Rosemount DP cell is much faster than indicated in the specification which is based on the traditional instrument-air-step-response measurement method. Furthermore, the actual time constant is much faster than that assumed in the safety analysis report. An examination of the instrument-air-step-response method indicates that is produces conservative estimates of time constants, especially for small time constants. If further work confirms this finding it suggests that the actual time constant may be increased considerably without exceeding the time constant assumed in the safety analysis. (author)

  7. Accurate Measurement of the Effects of All Amino-Acid Mutations on Influenza Hemagglutinin.

    Science.gov (United States)

    Doud, Michael B; Bloom, Jesse D

    2016-06-03

    Influenza genes evolve mostly via point mutations, and so knowing the effect of every amino-acid mutation provides information about evolutionary paths available to the virus. We and others have combined high-throughput mutagenesis with deep sequencing to estimate the effects of large numbers of mutations to influenza genes. However, these measurements have suffered from substantial experimental noise due to a variety of technical problems, the most prominent of which is bottlenecking during the generation of mutant viruses from plasmids. Here we describe advances that ameliorate these problems, enabling us to measure with greatly improved accuracy and reproducibility the effects of all amino-acid mutations to an H1 influenza hemagglutinin on viral replication in cell culture. The largest improvements come from using a helper virus to reduce bottlenecks when generating viruses from plasmids. Our measurements confirm at much higher resolution the results of previous studies suggesting that antigenic sites on the globular head of hemagglutinin are highly tolerant of mutations. We also show that other regions of hemagglutinin-including the stalk epitopes targeted by broadly neutralizing antibodies-have a much lower inherent capacity to tolerate point mutations. The ability to accurately measure the effects of all influenza mutations should enhance efforts to understand and predict viral evolution.

  8. Accurate Measurement of the Effects of All Amino-Acid Mutations on Influenza Hemagglutinin

    Directory of Open Access Journals (Sweden)

    Michael B. Doud

    2016-06-01

    Full Text Available Influenza genes evolve mostly via point mutations, and so knowing the effect of every amino-acid mutation provides information about evolutionary paths available to the virus. We and others have combined high-throughput mutagenesis with deep sequencing to estimate the effects of large numbers of mutations to influenza genes. However, these measurements have suffered from substantial experimental noise due to a variety of technical problems, the most prominent of which is bottlenecking during the generation of mutant viruses from plasmids. Here we describe advances that ameliorate these problems, enabling us to measure with greatly improved accuracy and reproducibility the effects of all amino-acid mutations to an H1 influenza hemagglutinin on viral replication in cell culture. The largest improvements come from using a helper virus to reduce bottlenecks when generating viruses from plasmids. Our measurements confirm at much higher resolution the results of previous studies suggesting that antigenic sites on the globular head of hemagglutinin are highly tolerant of mutations. We also show that other regions of hemagglutinin—including the stalk epitopes targeted by broadly neutralizing antibodies—have a much lower inherent capacity to tolerate point mutations. The ability to accurately measure the effects of all influenza mutations should enhance efforts to understand and predict viral evolution.

  9. Accurate measurement of bromine contents in plastic samples by instrumental neutron activation analysis.

    Science.gov (United States)

    Kim, I J; Lee, K S; Hwang, E; Min, H S; Yim, Y H

    2013-03-26

    Accurate measurements of bromine contents in plastic samples were made by the direct comparator instrumental neutron activation analysis (INAA). Individual factors affecting the measurements were comprehensively evaluated and compensated, including the volatility loss of bromine from standard comparators, the background bromine level in the filter papers used for preparation of the standard comparators, nuclear interference, γ-ray spectral interference and the variance among replicates of the samples. Uncertainty contributions from those factors were thoroughly evaluated and included in the uncertainty budgeting of the INAA measurement. (81)Br was chosen as the target isotope, and the INAA measurements for bromine were experimentally confirmed to exhibit good linearity within a bromine content range of 10-170 μg. The established method has been applied to the analysis of eight plastic samples: four commercially available certified reference materials (CRMs) of polyethylene and polystyrene and four acrylonitrile butadiene styrene (ABS) samples prepared as the candidate reference materials (KRISS CRM 113-01-012, -013, -014 and -015). The bromine contents of the samples were calculated at three different γ-ray energies and compared, showing good agreement. The results of the four CRMs also showed good consistency with their certified values within the stated uncertainties. Finally, the bromine contents of the ABS samples were determined with expanded uncertainties (at a 95% level of confidence) between 2.5% and 5% in a bromine content range of 25-900 mg kg(-1). Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Fast and accurate enzyme activity measurements using a chip-based microfluidic calorimeter.

    Science.gov (United States)

    van Schie, Morten M C H; Ebrahimi, Kourosh Honarmand; Hagen, Wilfred R; Hagedoorn, Peter-Leon

    2018-03-01

    Recent developments in microfluidic and nanofluidic technologies have resulted in development of new chip-based microfluidic calorimeters with potential use in different fields. One application would be the accurate high-throughput measurement of enzyme activity. Calorimetry is a generic way to measure activity of enzymes, but unlike conventional calorimeters, chip-based calorimeters can be easily automated and implemented in high-throughput screening platforms. However, application of chip-based microfluidic calorimeters to measure enzyme activity has been limited due to problems associated with miniaturization such as incomplete mixing and a decrease in volumetric heat generated. To address these problems we introduced a calibration method and devised a convenient protocol for using a chip-based microfluidic calorimeter. Using the new calibration method, the progress curve of alkaline phosphatase, which has product inhibition for phosphate, measured by the calorimeter was the same as that recorded by UV-visible spectroscopy. Our results may enable use of current chip-based microfluidic calorimeters in a simple manner as a tool for high-throughput screening of enzyme activity with potential applications in drug discovery and enzyme engineering. Copyright © 2017. Published by Elsevier Inc.

  11. Volume of preclinical xenograft tumors is more accurately assessed by ultrasound imaging than manual caliper measurements.

    Science.gov (United States)

    Ayers, Gregory D; McKinley, Eliot T; Zhao, Ping; Fritz, Jordan M; Metry, Rebecca E; Deal, Brenton C; Adlerz, Katrina M; Coffey, Robert J; Manning, H Charles

    2010-06-01

    The volume of subcutaneous xenograft tumors is an important metric of disease progression and response to therapy in preclinical drug development. Noninvasive imaging technologies suitable for measuring xenograft volume are increasingly available, yet manual calipers, which are susceptible to inaccuracy and bias, are routinely used. The goal of this study was to quantify and compare the accuracy, precision, and inter-rater variability of xenograft tumor volume assessment by caliper measurements and ultrasound imaging. Subcutaneous xenograft tumors derived from human colorectal cancer cell lines (DLD1 and SW620) were generated in athymic nude mice. Experienced independent reviewers segmented 3-dimensional ultrasound data sets and collected manual caliper measurements resulting in tumor volumes. Imaging- and caliper-derived volumes were compared with the tumor mass, the reference standard, determined after resection. Bias, precision, and inter-rater differences were estimated for each mouse among reviewers. Bootstrapping was used to estimate mean and confidence intervals of variance components, intraclass correlation coefficients (ICCs), and confidence intervals for each source of variation. The average deviation from the true volume and inter-rater differences were significantly lower for ultrasound volumes compared with caliper volumes (P = .0005 and .001, respectively). Reviewer ICCs for ultrasound and caliper measurements were similarly low (1%), yet caliper volume variance was 1.3-fold higher than for ultrasound. Ultrasound imaging more accurately, precisely, and reproducibly reflects xenograft tumor volume than caliper measurements. These data suggest that preclinical studies using the xenograft burden as a surrogate end point measured by ultrasound imaging require up to 30% fewer animals to reach statistical significance compared with analogous studies using caliper measurements.

  12. Accurate measurement of the optical activity of alanine crystals and the determination of their absolute chirality

    Science.gov (United States)

    Ishikawa, Kazuhiko; Terasawa, Yukana; Tanaka, Masahito; Asahi, Toru

    2017-05-01

    Wavelength dependence measurements of the chiroptical properties in alanine crystals have so far been unsuccessful using conventional spectroscopic techniques. We describe our attempts to measure the wavelength dependence of the optical activity in L- and D-alanine crystals along each crystallographic axis, and to determine the absolute chirality of alanine crystals by correlating the absolute structure to the optical activity using an x-ray diffractometer and a generalized high accuracy universal polarimeter. We have succeeded in accurately measuring the optical rotatory dispersion in the direction, which shows that the optical rotation of the D-alanine crystal is dextrorotatory and that of the L-alanine crystal is laevorotatory, thereby determining the absolute chirality. Furthermore, comparison with the optical activity in solution shows that the optical activity in alanine crystals is different not only in value, but also in the sign. These results have led us to conclude that the optical rotatory power in the crystalline state should not be simply the summation of molecular optical rotatory power values. We propose the necessity of a theory, which contains the contribution of molecular interactions within the crystal, in order to calculate the optical rotatory power of the crystalline state.

  13. Accurate Fluid Level Measurement in Dynamic Environment Using Ultrasonic Sensor and ν-SVM

    Directory of Open Access Journals (Sweden)

    Jenny TERZIC

    2009-10-01

    Full Text Available A fluid level measurement system based on a single Ultrasonic Sensor and Support Vector Machines (SVM based signal processing and classification system has been developed to determine the fluid level in automotive fuel tanks. The novel approach based on the ν-SVM classification method uses the Radial Basis Function (RBF to compensate for the measurement error induced by the sloshing effects in the tank caused by vehicle motion. A broad investigation on selected pre-processing filters, namely, Moving Mean, Moving Median, and Wavelet filter, has also been presented. Field drive trials were performed under normal driving conditions at various fuel volumes ranging from 5 L to 50 L to acquire sample data from the ultrasonic sensor for the training of SVM model. Further drive trials were conducted to obtain data to verify the SVM results. A comparison of the accuracy of the predicted fluid level obtained using SVM and the pre-processing filters is provided. It is demonstrated that the ν-SVM model using the RBF kernel function and the Moving Median filter has produced the most accurate outcome compared with the other signal filtration methods in terms of fluid level measurement.

  14. The accurate measurement of second virial coefficients using self-interaction chromatography: experimental considerations.

    Science.gov (United States)

    Quigley, A; Heng, J Y Y; Liddell, J M; Williams, D R

    2013-11-01

    Measurement of B22, the second virial coefficient, is an important technique for describing the solution behaviour of proteins, especially as it relates to precipitation, aggregation and crystallisation phenomena. This paper describes the best practise for calculating B22 values from self-interaction chromatograms (SIC) for aqueous protein solutions. Detailed analysis of SIC peak shapes for lysozyme shows that non-Gaussian peaks are commonly encountered for SIC, with typical peak asymmetries of 10%. This asymmetry reflects a non-linear chromatographic retention process, in this case heterogeneity of the protein-protein interactions. Therefore, it is important to use the centre of mass calculations for determining accurate retention volumes and thus B22 values. Empirical peak maximum chromatogram analysis, often reported in the literature, can result in errors of up to 50% in B22 values. A methodology is reported here for determining both the mean and the variance in B22 from SIC experiments, includes a correction for normal longitudinal peak broadening. The variance in B22 due to chemical effects is quantified statistically and is a measure of the heterogeneity of protein-protein interactions in solution. In the case of lysozyme, a wide range of B22 values are measured which can vary significantly from the average B22 values. Copyright © 2013. Published by Elsevier B.V.

  15. Self-Interaction Chromatography of mAbs: Accurate Measurement of Dead Volumes.

    Science.gov (United States)

    Hedberg, S H M; Heng, J Y Y; Williams, D R; Liddell, J M

    2015-12-01

    Measurement of the second virial coefficient B22 for proteins using self-interaction chromatography (SIC) is becoming an increasingly important technique for studying their solution behaviour. In common with all physicochemical chromatographic methods, measuring the dead volume of the SIC packed column is crucial for accurate retention data; this paper examines best practise for dead volume determination. SIC type experiments using catalase, BSA, lysozyme and a mAb as model systems are reported, as well as a number of dead column measurements. It was observed that lysozyme and mAb interacted specifically with Toyopearl AF-Formyl dead columns depending upon pH and [NaCl], invalidating their dead volume usage. Toyopearl AF-Amino packed dead columns showed no such problems and acted as suitable dead columns without any solution condition dependency. Dead volume determinations using dextran MW standards with protein immobilised SIC columns provided dead volume estimates close to those obtained using Toyopearl AF-Amino dead columns. It is concluded that specific interactions between proteins, including mAbs, and select SIC support phases can compromise the use of some standard approaches for estimating the dead volume of SIC columns. Two other methods were shown to provide good estimates for the dead volume.

  16. Artificial absorption creation for more accurate tunable diode laser absorption spectroscopy measurement

    Science.gov (United States)

    Wei, Wei; Chang, Jun; Cao, Lihua; Liu, Yuanyuan; Chen, Xi; Zhu, Cunguang; Qin, Zengguang

    2017-09-01

    A novel strategy for more accurate tunable diode laser absorption spectroscopy (TDLAS) measurement is presented. This method is immune to non-absorption transmission losses, and allows dead zone removal for ultra-low concentration detection, and reference point selection at atmospheric pressure. The method adjusts laser emission and creates artificial absorption peaks according to requirements. By creating an artificial absorption peak next to the real absorption zone, calibration is not necessary. The developed method can be applied to not only wavelength modulation spectroscopy (WMS) but also direct absorption (DA). In WMS, the method does not need two harmonic signals, resulting in higher reliability, better performance, and no electro-optical gain uncertainty. At the same time, non-absorption transmission losses effect is suppressed from 70% to 0.425% with DA and from 70% to 0.225% with WMS method. When the artificial absorption peak coincides with the real one, the dead zone of measurement can be removed to give a lower detection limit, and water vapor still can be detected when concentration is lower than 0.2 ppm in our experiment. Reference point selection uncertainty with the DA method, especially when the signal-to-noise ratio is low and absorption line is broad, can also be facilitated. And the uncertainty of reference point selection is improved from 6% to 0.8% by measuring reference point amplitude. The method is demonstrated and validated by WMS and DA measurements of water vapor (1 atm, 296 K, 1368.597 nm). The measurement results obtained using the new method reveal its promise in TDLAS.

  17. An Inexpensive, Stable, and Accurate Relative Humidity Measurement Method for Challenging Environments.

    Science.gov (United States)

    Zhang, Wei; Ma, Hong; Yang, Simon X

    2016-03-18

    In this research, an improved psychrometer is developed to solve practical issues arising in the relative humidity measurement of challenging drying environments for meat manufacturing in agricultural and agri-food industries. The design in this research focused on the structure of the improved psychrometer, signal conversion, and calculation methods. The experimental results showed the effect of varying psychrometer structure on relative humidity measurement accuracy. An industrial application to dry-cured meat products demonstrated the effective performance of the improved psychrometer being used as a relative humidity measurement sensor in meat-drying rooms. In a drying environment for meat manufacturing, the achieved measurement accuracy for relative humidity using the improved psychrometer was ±0.6%. The system test results showed that the improved psychrometer can provide reliable and long-term stable relative humidity measurements with high accuracy in the drying system of meat products.

  18. Development of a scattering probability method for accurate vapor fraction measurements by neutron radiography

    CERN Document Server

    Joo, H

    1999-01-01

    Recent test results indicated drawbacks associated with the simple exponential attenuation method (SEAM) as currently applied to neutron radiography measurements to determine vapor fractions in a hydrogenous two-phase flow in a metallic conduit. The scattering component of the neutron beam intensity exiting the flow system is not adequately accounted for by SEAM, and this leads to inaccurate results. To properly account for the scattering effect, a neutron scattering probability method (SPM) is developed. The method applies a neutron-hydrogen scattering kernel to scattered thermal neutrons that leave the incident beam in narrow conduits but eventually show up elsewhere in the measurements. The SPM has been tested with known vapor (void) distributions within an acrylic disk and a water/vapor channel. The vapor (void) fractions deduced by SPM are in good agreement with the known exact values. Details of the scattering correction method and the test results are discussed.

  19. An accurate low current measurement circuit for heavy iron beam current monitor

    International Nuclear Information System (INIS)

    Zhou Chaoyang; Su Hong; Mao Ruishi; Dong Chengfu; Qian Yi; Kong Jie

    2012-01-01

    Heavy-ion beams at 10 6 particles per second have been applied to the treatment of deep-seated inoperable tumors in the therapy terminal of the Heavy Ion Research Facility in Lanzhou (HIRFL) which is located at the Institute of Modern Physics, Chinese Academy of Sciences (IMP, CAS). An accurate low current measurement circuit following a Faraday cup was developed to monitor the beam current at pA range. The circuit consisted of a picoammeter with a bandwidth of 1 kHz and a gated integrator (GI). A low input bias current precision amplifier and new guarding and shielding techniques were used in the picoammeter circuit which allowed as to measure current less than 1 pA with a current gain of 0.22 V/pA and noise less than 10 fA. This paper will also describe a novel compensation approach which reduced the charge injection from switches in the GI to 10 −18 C, and a T-switch configuration which was used to eliminate leakage current in the reset switch.

  20. Can Wearable Devices Accurately Measure Heart Rate Variability? A Systematic Review.

    Science.gov (United States)

    Georgiou, Konstantinos; Larentzakis, Andreas V; Khamis, Nehal N; Alsuhaibani, Ghadah I; Alaska, Yasser A; Giallafos, Elias J

    2018-03-01

    A growing number of wearable devices claim to provide accurate, cheap and easily applicable heart rate variability (HRV) indices. This is mainly accomplished by using wearable photoplethysmography (PPG) and/or electrocardiography (ECG), through simple and non-invasive techniques, as a substitute of the gold standard RR interval estimation through electrocardiogram. Although the agreement between pulse rate variability (PRV) and HRV has been evaluated in the literature, the reported results are still inconclusive especially when using wearable devices. The purpose of this systematic review is to investigate if wearable devices provide a reliable and precise measurement of classic HRV parameters in rest as well as during exercise. A search strategy was implemented to retrieve relevant articles from MEDLINE and SCOPUS databases, as well as, through internet search. The 308 articles retrieved were reviewed for further evaluation according to the predetermined inclusion/exclusion criteria. Eighteen studies were included. Sixteen of them integrated ECG - HRV technology and two of them PPG - PRV technology. All of them examined wearable devices accuracy in RV detection during rest, while only eight of them during exercise. The correlation between classic ECG derived HRV and the wearable RV ranged from very good to excellent during rest, yet it declined progressively as exercise level increased. Wearable devices may provide a promising alternative solution for measuring RV. However, more robust studies in non-stationary conditions are needed using appropriate methodology in terms of number of subjects involved, acquisition and analysis techniques implied.

  1. Accurate measurement of the time delay in the response of the LIGO gravitational wave detectors

    Energy Technology Data Exchange (ETDEWEB)

    Aso, Yoichi; Kalmus, Peter; Matone, Luca; Marka, Szabolcs [Department of Physics, Columbia University, New York, NY 10027 (United States); Goetz, Evan [University of Michigan, Ann Arbor, MI 48109 (United States); Myers, Joshua; Savage, Rick; Schwinberg, Paul; Sigg, Daniel [LIGO Hanford Observatory, Richland, WA 99352 (United States); O' Reilly, Brian [LIGO Livingston Observatory, Livingston, LA 70754 (United States); Siemens, Xavier [Department of Physics, University of Wisconsin at Milwaukee, Milwaukee, WI 53211 (United States); Smith, Nicolas, E-mail: aso@caltech.ed [LIGO Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

    2009-03-07

    We present a method to precisely calibrate the time delay in a long baseline gravitational-wave interferometer. An accurate time stamp is crucial for data analysis of gravitational wave detectors, especially when performing coincidence and correlation analyses between multiple detectors. Our method uses an intensity-modulated radiation pressure force to actuate on the mirrors. The time delay is measured by comparing the phase of the signal at the actuation point with the phase of the recorded signal within the calibrated data stream used for gravitational wave searches. Because the signal-injection path is independent of the interferometer's control system, which is used for the standard calibration, this method can be an independent verification of the timing error in the system. A measurement performed with the 4 km interferometer at the LIGO Hanford Observatory shows a 1 mus relative accuracy when averaging over 50 min. Our understanding of the systematic time delay in the detector response has reached the level of 10 mus.

  2. Use of a stopwatch to measure ejaculatory latency may not be accurate among Indian patients

    Science.gov (United States)

    Bhat, Gajanan Shripad; Shastry, Anuradha

    2017-01-01

    Introduction: Although the use of a stopwatch is recommended to record intravaginal ejaculatory latency time (IELT) for premature ejaculation, there is no Indian literature which assesses the reliability of this method among our patients. Hence, we assessed the accuracy of stopwatch-measured IELT and compared it with other methods such as number of thrusts and self-assessed IELT in an Indian context. Methods: Between January 2015 and December 2015, couples with premature ejaculation (PE) confirmed with the Premature Ejaculation Diagnostic Tool were enrolled in this study. They were asked to report self-assessed IELT for the first 2 weeks, number of thrusts before ejaculation following vaginal penetration for the next 2 weeks, and stopwatch-clocked IELT for the last 2 weeks. At each 2-week interval, the couples answered erectile/ejaculatory performance anxiety index questionnaire (EPAI). The data were analyzed at the end of 6 weeks. Results: A total of 42 couples with an average married life of 5.53 years were included in the study. Average stopwatch-clocked IELT was almost 1 min more than the self-reported IELT, which was statistically significant. The average number of thrusts reported was 6.31. Anxiety on the EPAI scale was maximum while using stopwatch to measure IELT. Conclusion: Use of stopwatch to clock the IELT does not appear to represent true IELT in Indian patients. Self-assessed IELT correlated more accurately with symptoms of PE. PMID:29021654

  3. External urethral sphincter pressure measurement: an accurate method for the diagnosis of detrusor external sphincter dyssynergia?

    Directory of Open Access Journals (Sweden)

    Carlos H Suzuki Bellucci

    Full Text Available Combined pelvic floor electromyography (EMG and videocystourethrography (VCUG during urodynamic investigation are the most acceptable and widely agreed methods for diagnosing detrusor external sphincter dyssynergia (DESD. Theoretically, external urethral sphincter pressure (EUSP measurement would provide enough information for the diagnosis of DESD and could simplify the urodynamic investigation replacing combined pelvic floor EMG and VCUG. Thus, we evaluated the diagnostic accuracy of EUSP measurement for DESD. PATIENTS #ENTITYSTARTX00026;A consecutive series of 72 patients (36 women, 36 men with neurogenic lower urinary tract dysfunction able to void spontaneously was prospectively evaluated at a single university spinal cord injury center. Diagnosis of DESD using EUSP measurement (index test versus combined pelvic floor EMG and VCUG (reference standard was assessed according to the recommendations of the Standards for Reporting of Diagnostic Accuracy Initiative.Using EUSP measurement (index test and combined pelvic floor EMG and VCUR (reference standard, DESD was diagnosed in 10 (14% and in 41 (57% patients, respectively. More than half of the patients presented discordant diagnosis between the index test and the reference standard. Among 41 patients with DESD diagnosed by combined pelvic floor EMG and VCUR, EUSP measurement identified only 6 patients. EUSP measurement had a sensitivity of 15% (95% CI 5%-25%, specificity of 87% (95% CI 76%-98%, positive predictive value of 60% (95% CI 30%-90%, and negative predictive value of 56% (95% CI 44%-68% for the diagnosis of DESD.For diagnosis of DESD, EUSP measurement is inaccurate and cannot replace combined pelvic floor EMG and VCUR.

  4. Accurate and precise Pb isotope ratio measurements in environmental samples by MC-ICP-MS

    Science.gov (United States)

    Weiss, Dominik J.; Kober, Bernd; Dolgopolova, Alla; Gallagher, Kerry; Spiro, Baruch; Le Roux, Gaël; Mason, Thomas F. D.; Kylander, Malin; Coles, Barry J.

    2004-04-01

    Analytical protocols for accurate and precise Pb isotope ratio determinations in peat, lichen, vegetable, chimney dust, and ore-bearing granites using MC-ICP-MS and their application to environmental studies are presented. Acid dissolution of various matrix types was achieved using high temperature/high pressure microwave and hot plate digestion procedures. The digests were passed through a column packed with EiChrom Sr-resin employing only hydrochloric acid and one column passage. This simplified column chemistry allowed high sample throughput. Typically, internal precisions for approximately 30 ng Pb were below 100 ppm (+/-2[sigma]) on all Pb ratios in all matrices. Thallium was employed to correct for mass discrimination effects and the achieved accuracy was below 80 ppm for all ratios. This involved an optimization procedure for the 205Tl/203Tl ratio using least square fits relative to certified NIST-SRM 981 Pb values. The long-term reproducibility (+/-2[sigma]) for the NIST-SRM 981 Pb standard over a 5-month period (35 measurements) was better than 350 ppm for all ratios. Selected ore-bearing granites were measured with TIMS and MC-ICP-MS and showed good correlation (e.g., r=0.999 for 206Pb/207Pb ratios, slope=0.996, n=13). Mass bias and signal intensities of Tl spiked into natural (after matrix separation) and in synthetic samples did not differ significantly, indicating that any residual components of the complex peat and lichen matrix did not influence mass bias correction. Environmental samples with very different matrices were analyzed during two different studies: (i) lichens, vegetables, and chimney dust around a Cu smelter in the Urals, and (ii) peat samples from an ombrotrophic bog in the Faroe Islands. The presented procedure for sample preparation, mass spectrometry, and data processing tools resulted in accurate and precise Pb isotope data that allowed the reliable differentiation and identification of Pb sources with variations as small as 0

  5. A Cost-Effective Transparency-Based Digital Imaging for Efficient and Accurate Wound Area Measurement

    Science.gov (United States)

    Li, Pei-Nan; Li, Hong; Wu, Mo-Li; Wang, Shou-Yu; Kong, Qing-You; Zhang, Zhen; Sun, Yuan; Liu, Jia; Lv, De-Cheng

    2012-01-01

    Wound measurement is an objective and direct way to trace the course of wound healing and to evaluate therapeutic efficacy. Nevertheless, the accuracy and efficiency of the current measurement methods need to be improved. Taking the advantages of reliability of transparency tracing and the accuracy of computer-aided digital imaging, a transparency-based digital imaging approach is established, by which data from 340 wound tracing were collected from 6 experimental groups (8 rats/group) at 8 experimental time points (Day 1, 3, 5, 7, 10, 12, 14 and 16) and orderly archived onto a transparency model sheet. This sheet was scanned and its image was saved in JPG form. Since a set of standard area units from 1 mm2 to 1 cm2 was integrated into the sheet, the tracing areas in JPG image were measured directly, using the “Magnetic lasso tool” in Adobe Photoshop program. The pixel values/PVs of individual outlined regions were obtained and recorded in an average speed of 27 second/region. All PV data were saved in an excel form and their corresponding areas were calculated simultaneously by the formula of Y (PV of the outlined region)/X (PV of standard area unit) × Z (area of standard unit). It took a researcher less than 3 hours to finish area calculation of 340 regions. In contrast, over 3 hours were expended by three skillful researchers to accomplish the above work with traditional transparency-based method. Moreover, unlike the results obtained traditionally, little variation was found among the data calculated by different persons and the standard area units in different sizes and shapes. Given its accurate, reproductive and efficient properties, this transparency-based digital imaging approach would be of significant values in basic wound healing research and clinical practice. PMID:22666449

  6. A cost-effective transparency-based digital imaging for efficient and accurate wound area measurement.

    Directory of Open Access Journals (Sweden)

    Pei-Nan Li

    Full Text Available Wound measurement is an objective and direct way to trace the course of wound healing and to evaluate therapeutic efficacy. Nevertheless, the accuracy and efficiency of the current measurement methods need to be improved. Taking the advantages of reliability of transparency tracing and the accuracy of computer-aided digital imaging, a transparency-based digital imaging approach is established, by which data from 340 wound tracing were collected from 6 experimental groups (8 rats/group at 8 experimental time points (Day 1, 3, 5, 7, 10, 12, 14 and 16 and orderly archived onto a transparency model sheet. This sheet was scanned and its image was saved in JPG form. Since a set of standard area units from 1 mm(2 to 1 cm(2 was integrated into the sheet, the tracing areas in JPG image were measured directly, using the "Magnetic lasso tool" in Adobe Photoshop program. The pixel values/PVs of individual outlined regions were obtained and recorded in an average speed of 27 second/region. All PV data were saved in an excel form and their corresponding areas were calculated simultaneously by the formula of Y (PV of the outlined region/X (PV of standard area unit × Z (area of standard unit. It took a researcher less than 3 hours to finish area calculation of 340 regions. In contrast, over 3 hours were expended by three skillful researchers to accomplish the above work with traditional transparency-based method. Moreover, unlike the results obtained traditionally, little variation was found among the data calculated by different persons and the standard area units in different sizes and shapes. Given its accurate, reproductive and efficient properties, this transparency-based digital imaging approach would be of significant values in basic wound healing research and clinical practice.

  7. A flux monitoring method for easy and accurate flow rate measurement in pressure-driven flows.

    Science.gov (United States)

    Siria, Alessandro; Biance, Anne-Laure; Ybert, Christophe; Bocquet, Lydéric

    2012-03-07

    We propose a low-cost and versatile method to measure flow rate in microfluidic channels under pressure-driven flows, thereby providing a simple characterization of the hydrodynamic permeability of the system. The technique is inspired by the current monitoring method usually employed to characterize electro-osmotic flows, and makes use of the measurement of the time-dependent electric resistance inside the channel associated with a moving salt front. We have successfully tested the method in a micrometer-size channel, as well as in a complex microfluidic channel with a varying cross-section, demonstrating its ability in detecting internal shape variations.

  8. The use of a robotic tibial rotation device and an electromagnetic tracking system to accurately reproduce the clinical dial test.

    Science.gov (United States)

    Stinton, S K; Siebold, R; Freedberg, H; Jacobs, C; Branch, T P

    2016-03-01

    The purpose of this study was to: (1) determine whether a robotic tibial rotation device and an electromagnetic tracking system could accurately reproduce the clinical dial test at 30° of knee flexion; (2) compare rotation data captured at the footplates of the robotic device to tibial rotation data measured using an electromagnetic sensor on the proximal tibia. Thirty-two unilateral ACL-reconstructed patients were examined using a robotic tibial rotation device that mimicked the dial test. The data reported in this study is only from the healthy legs of these patients. Torque was applied through footplates and was measured using servomotors. Lower leg motion was measured at the foot using the motors. Tibial motion was also measured through an electromagnetic tracking system and a sensor on the proximal tibia. Load-deformation curves representing rotational motion of the foot and tibia were compared using Pearson's correlation coefficients. Off-axis motions including medial-lateral translation and anterior-posterior translation were also measured using the electromagnetic system. The robotic device and electromagnetic system were able to provide axial rotation data and translational data for the tibia during the dial test. Motion measured at the foot was not correlated to motion of the tibial tubercle in internal rotation or in external rotation. The position of the tibial tubercle was 26.9° ± 11.6° more internally rotated than the foot at torque 0 Nm. Medial-lateral translation and anterior-posterior translation were combined to show the path of the tubercle in the coronal plane during tibial rotation. The information captured during a manual dial test includes both rotation of the tibia and proximal tibia translation. All of this information can be captured using a robotic tibial axial rotation device with an electromagnetic tracking system. The pathway of the tibial tubercle during tibial axial rotation can provide additional information about knee

  9. Accurate human limb angle measurement: sensor fusion through Kalman, least mean squares and recursive least-squares adaptive filtering

    Science.gov (United States)

    Olivares, A.; Górriz, J. M.; Ramírez, J.; Olivares, G.

    2011-02-01

    Inertial sensors are widely used in human body motion monitoring systems since they permit us to determine the position of the subject's limbs. Limb angle measurement is carried out through the integration of the angular velocity measured by a rate sensor and the decomposition of the components of static gravity acceleration measured by an accelerometer. Different factors derived from the sensors' nature, such as the angle random walk and dynamic bias, lead to erroneous measurements. Dynamic bias effects can be reduced through the use of adaptive filtering based on sensor fusion concepts. Most existing published works use a Kalman filtering sensor fusion approach. Our aim is to perform a comparative study among different adaptive filters. Several least mean squares (LMS), recursive least squares (RLS) and Kalman filtering variations are tested for the purpose of finding the best method leading to a more accurate and robust limb angle measurement. A new angle wander compensation sensor fusion approach based on LMS and RLS filters has been developed.

  10. Accurate human limb angle measurement: sensor fusion through Kalman, least mean squares and recursive least-squares adaptive filtering

    International Nuclear Information System (INIS)

    Olivares, A; Olivares, G; Górriz, J M; Ramírez, J

    2011-01-01

    Inertial sensors are widely used in human body motion monitoring systems since they permit us to determine the position of the subject's limbs. Limb angle measurement is carried out through the integration of the angular velocity measured by a rate sensor and the decomposition of the components of static gravity acceleration measured by an accelerometer. Different factors derived from the sensors' nature, such as the angle random walk and dynamic bias, lead to erroneous measurements. Dynamic bias effects can be reduced through the use of adaptive filtering based on sensor fusion concepts. Most existing published works use a Kalman filtering sensor fusion approach. Our aim is to perform a comparative study among different adaptive filters. Several least mean squares (LMS), recursive least squares (RLS) and Kalman filtering variations are tested for the purpose of finding the best method leading to a more accurate and robust limb angle measurement. A new angle wander compensation sensor fusion approach based on LMS and RLS filters has been developed

  11. Accurate permittivity measurements for microwave imaging via ultra-wideband removal of spurious reflectors.

    Science.gov (United States)

    Pelletier, Mathew G; Viera, Joseph A; Wanjura, John; Holt, Greg

    2010-01-01

    The use of microwave imaging is becoming more prevalent for detection of interior hidden defects in manufactured and packaged materials. In applications for detection of hidden moisture, microwave tomography can be used to image the material and then perform an inverse calculation to derive an estimate of the variability of the hidden material, such internal moisture, thereby alerting personnel to damaging levels of the hidden moisture before material degradation occurs. One impediment to this type of imaging occurs with nearby objects create strong reflections that create destructive and constructive interference, at the receiver, as the material is conveyed past the imaging antenna array. In an effort to remove the influence of the reflectors, such as metal bale ties, research was conducted to develop an algorithm for removal of the influence of the local proximity reflectors from the microwave images. This research effort produced a technique, based upon the use of ultra-wideband signals, for the removal of spurious reflections created by local proximity reflectors. This improvement enables accurate microwave measurements of moisture in such products as cotton bales, as well as other physical properties such as density or material composition. The proposed algorithm was shown to reduce errors by a 4:1 ratio and is an enabling technology for imaging applications in the presence of metal bale ties.

  12. On the tip calibration for accurate modulus measurement by contact resonance atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Passeri, D., E-mail: daniele.passeri@uniroma1.it [Department of Basic and Applied Sciences for Engineering, University of Rome Sapienza, Via A. Scarpa 16, 00161 Rome (Italy); Rossi, M. [Department of Basic and Applied Sciences for Engineering, University of Rome Sapienza, Via A. Scarpa 16, 00161 Rome (Italy); Centro di Ricerca per le Nanotecnologie Applicate all' Ingegneria della Sapienza (CNIS), University of Rome Sapienza, Piazzale A. Moro 5, 00185 Rome (Italy); Vlassak, J.J. [School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge, MA 02138 (United States)

    2013-05-15

    Accurate quantitative elastic modulus measurements using contact resonance atomic force microscopy require the calibration of geometrical and mechanical properties of the tip as well as the choice of a suitable model for describing the cantilever-tip-sample system. In this work, we demonstrate with both simulations and experiments that the choice of the model influences the results of the calibration. Neglecting lateral force results in the underestimation of the tip indentation modulus and in the overestimation of the tip-sample contact radius. We propose a new approach to the calibration and data analysis, where lateral forces and cantilever inclination are neglected (which simplifies the calculations) and the tip parameters are assumed as fictitious. - Highlights: ► A calibration procedure is proposed for quantitative contact resonance AFM. ► It allows the use of simple analytical model that neglects lateral forces. ► Tip parameters are used as fictitious parameters. ► The approach is demonstrated with simulations and experiments.

  13. A Facility for Accurate Heat Load and Mass Leak Measurements on Superfluid Helium Valves

    CERN Document Server

    Bézaguet, Alain-Arthur; Ferlin, G; Losserand-Madoux, R; Perin, A; Vandoni, Giovanna; Van Weelderen, R

    1999-01-01

    The superconducting magnets of the Large Hadron Collider (LHC) will be protected by safety relief valves operating at 1.9 K in superfluid helium (HeII). A test facility was developed to precisely determine the heat load and the mass leakage of cryogenic valves with HeII at their inlet. The temperature of the valve inlet can be varied from 1.8 K to 2 K for pressures up to 3.5 bar. The valve outlet pipe temperature can be regulated between 5 K and 20 K. The heat flow is measured with high precision using a Kapitza-resistance heatmeter and is also crosschecked by a vaporization measurement. After calibration, a precision of 10 mW for heat flows up to 1.1 W has been achieved. The helium leak can be measured up to 15 mg/s with an accuracy of 0.2 mg/s. We present a detailed description of the test facility and the measurements showing its performances.

  14. Accurate measurement of transgene copy number in crop plants using droplet digital PCR.

    Science.gov (United States)

    Collier, Ray; Dasgupta, Kasturi; Xing, Yan-Ping; Hernandez, Bryan Tarape; Shao, Min; Rohozinski, Dominica; Kovak, Emma; Lin, Jeanie; de Oliveira, Maria Luiza P; Stover, Ed; McCue, Kent F; Harmon, Frank G; Blechl, Ann; Thomson, James G; Thilmony, Roger

    2017-06-01

    Genetic transformation is a powerful means for the improvement of crop plants, but requires labor- and resource-intensive methods. An efficient method for identifying single-copy transgene insertion events from a population of independent transgenic lines is desirable. Currently, transgene copy number is estimated by either Southern blot hybridization analyses or quantitative polymerase chain reaction (qPCR) experiments. Southern hybridization is a convincing and reliable method, but it also is expensive, time-consuming and often requires a large amount of genomic DNA and radioactively labeled probes. Alternatively, qPCR requires less DNA and is potentially simpler to perform, but its results can lack the accuracy and precision needed to confidently distinguish between one- and two-copy events in transgenic plants with large genomes. To address this need, we developed a droplet digital PCR-based method for transgene copy number measurement in an array of crops: rice, citrus, potato, maize, tomato and wheat. The method utilizes specific primers to amplify target transgenes, and endogenous reference genes in a single duplexed reaction containing thousands of droplets. Endpoint amplicon production in the droplets is detected and quantified using sequence-specific fluorescently labeled probes. The results demonstrate that this approach can generate confident copy number measurements in independent transgenic lines in these crop species. This method and the compendium of probes and primers will be a useful resource for the plant research community, enabling the simple and accurate determination of transgene copy number in these six important crop species. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  15. Accurate fault location algorithm on power transmission lines with use of two-end unsynchronized measurements

    Directory of Open Access Journals (Sweden)

    Mohamed Dine

    2012-01-01

    Full Text Available This paper presents a new approach to fault location on power transmission lines. This approach uses two-end unsynchronised measurements of the line and benefits from the advantages of digital technology and numerical relaying, which are available today and can easily be applied for off-line analysis. The approach is to modify the apparent impedance method using a very simple first-order formula. The new method is independent of fault resistance, source impedances and pre-fault currents. In addition, the data volume communicated between relays is sufficiently small enough to be transmitted easily using a digital protection channel. The proposed approach is tested via digital simulation using MATLand the applied test results corroborate the superior performance of the proposed approach.

  16. Accurate test of chiral dynamics in the γp→π0p reaction.

    Science.gov (United States)

    Hornidge, D; Aguar Bartolomé, P; Annand, J R M; Arends, H J; Beck, R; Bekrenev, V; Berghäuser, H; Bernstein, A M; Braghieri, A; Briscoe, W J; Cherepnya, S; Dieterle, M; Downie, E J; Drexler, P; Fernández-Ramírez, C; Filkov, L V; Glazier, D I; Hall Barrientos, P; Heid, E; Hilt, M; Jaegle, I; Jahn, O; Jude, T C; Kashevarov, V L; Keshelashvili, I; Kondratiev, R; Korolija, M; Koulbardis, A; Krambrich, D; Kruglov, S; Krusche, B; Laffoley, A T; Lisin, V; Livingston, K; MacGregor, I J D; Mancell, J; Manley, D M; McNicoll, E F; Mekterovic, D; Metag, V; Micanovic, S; Middleton, D G; Moores, K W; Mushkarenkov, A; Nefkens, B M K; Oberle, M; Ostrick, M; Otte, P B; Oussena, B; Pedroni, P; Pheron, F; Polonski, A; Prakhov, S; Robinson, J; Rostomyan, T; Scherer, S; Schumann, S; Sikora, M H; Starostin, A; Supek, I; Thiel, M; Thomas, A; Tiator, L; Unverzagt, M; Watts, D P; Werthmüller, D; Witthauer, L

    2013-08-09

    A precision measurement of the differential cross sections dσ/dΩ and the linearly polarized photon asymmetry Σ≡(dσ⊥-dσ∥)/(dσ⊥+dσ∥) for the γp→π0p reaction in the near-threshold region has been performed with a tagged photon beam and almost 4π detector at the Mainz Microtron. The Glasgow-Mainz photon tagging facility along with the Crystal Ball/TAPS multiphoton detector system and a cryogenic liquid hydrogen target were used. These data allowed for a precise determination of the energy dependence of the real parts of the S- and all three P-wave amplitudes for the first time and provide the most stringent test to date of the predictions of chiral perturbation theory and its energy region of agreement with experiment.

  17. An accurate and efficient identification of children with psychosocial problems by means of computerized adaptive testing

    NARCIS (Netherlands)

    Vogels, Antonius G. C.; Jacobusse, Gert W.; Reijneveld, Symen A.

    2011-01-01

    Background: Questionnaires used by health services to identify children with psychosocial problems are often rather short. The psychometric properties of such short questionnaires are mostly less than needed for an accurate distinction between children with and without problems. We aimed to assess

  18. Bacterial Cytological Profiling (BCP as a Rapid and Accurate Antimicrobial Susceptibility Testing Method for Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    D.T. Quach

    2016-02-01

    Full Text Available Successful treatment of bacterial infections requires the timely administration of appropriate antimicrobial therapy. The failure to initiate the correct therapy in a timely fashion results in poor clinical outcomes, longer hospital stays, and higher medical costs. Current approaches to antibiotic susceptibility testing of cultured pathogens have key limitations ranging from long run times to dependence on prior knowledge of genetic mechanisms of resistance. We have developed a rapid antimicrobial susceptibility assay for Staphylococcus aureus based on bacterial cytological profiling (BCP, which uses quantitative fluorescence microscopy to measure antibiotic induced changes in cellular architecture. BCP discriminated between methicillin-susceptible (MSSA and -resistant (MRSA clinical isolates of S. aureus (n = 71 within 1–2 h with 100% accuracy. Similarly, BCP correctly distinguished daptomycin susceptible (DS from daptomycin non-susceptible (DNS S. aureus strains (n = 20 within 30 min. Among MRSA isolates, BCP further identified two classes of strains that differ in their susceptibility to specific combinations of beta-lactam antibiotics. BCP provides a rapid and flexible alternative to gene-based susceptibility testing methods for S. aureus, and should be readily adaptable to different antibiotics and bacterial species as new mechanisms of resistance or multidrug-resistant pathogens evolve and appear in mainstream clinical practice.

  19. Is Oral Temperature an Accurate Measurement of Deep Body Temperature? A Systematic Review

    Science.gov (United States)

    Mazerolle, Stephanie M.; Ganio, Matthew S.; Casa, Douglas J.; Vingren, Jakob; Klau, Jennifer

    2011-01-01

    Context: Oral temperature might not be a valid method to assess core body temperature. However, many clinicians, including athletic trainers, use it rather than criterion standard methods, such as rectal thermometry. Objective: To critically evaluate original research addressing the validity of using oral temperature as a measurement of core body temperature during periods of rest and changing core temperature. Data Sources: In July 2010, we searched the electronic databases PubMed, Scopus, Cumulative Index to Nursing and Allied Health Literature (CINAHL), SPORTDiscus, Academic Search Premier, and the Cochrane Library for the following concepts: core body temperature, oral, and thermometers. Controlled vocabulary was used, when available, as well as key words and variations of those key words. The search was limited to articles focusing on temperature readings and studies involving human participants. Data Synthesis: Original research was reviewed using the Physiotherapy Evidence Database (PEDro). Sixteen studies met the inclusion criteria and subsequently were evaluated by 2 independent reviewers. All 16 were included in the review because they met the minimal PEDro score of 4 points (of 10 possible points), with all but 2 scoring 5 points. A critical review of these studies indicated a disparity between oral and criterion standard temperature methods (eg, rectal and esophageal) specifically as the temperature increased. The difference was −0.50°C ± 0.31°C at rest and −0.58°C ± 0.75°C during a nonsteady state. Conclusions: Evidence suggests that, regardless of whether the assessment is recorded at rest or during periods of changing core temperature, oral temperature is an unsuitable diagnostic tool for determining body temperature because many measures demonstrated differences greater than the predetermined validity threshold of 0.27°C (0.5°F). In addition, the differences were greatest at the highest rectal temperatures. Oral temperature cannot

  20. Is there an accurate method to measure metabolic requirement of institutionalized children with spastic cerebral palsy?

    Science.gov (United States)

    Lee, Siu Pik Peggy; Cheung, Ka Ming; Ko, Chun Hung; Chiu, Heung Chin

    2011-07-01

    This study hypothesized that there is no difference between energy expenditure measured by indirect calorimetry (IC) and that estimated by predicted formulas compared with the actual intake of children with spastic cerebral palsy (CP). Fifteen children aged 3 to 18 years with spastic CP and associated complications were recruited. IC was used to measure mean energy expenditure (MEE) compared with 3 predicted equations for energy expenditure (PEE), including body surface area (BSA), the recommended daily allowance (RDA), and an equation designed specifically for patients with CP. Friedman and paired t tests were used to examine the variance between PEE and MEE. Intraclass correlation coefficient (ICC) was used to explore the correlation between MEE and PEE. The pretest and posttest core temperatures were compared using the Wilcoxon signed rank test. Mean ± standard deviation MEE was 800.5 ± 295.7 kcal/d; BSA was 1,213.4 ± 171.2 kcal/d; RDA was 1,928.1 ± 341.0 kcal/d; and CP was 1,603.1 ± 215.8 kcal/d. The actual diet intake provided 935.3 ± 222.9 kcal/d. Post hoc analysis revealed a significant difference between mean MEE and PEE (P children with spastic CP.

  1. A technique for fast and accurate measurement of hand volumes using Archimedes' principle.

    Science.gov (United States)

    Hughes, S; Lau, J

    2008-03-01

    A new technique for measuring hand volumes using Archimedes principle is described. The technique involves the immersion of a hand in a water container placed on an electronic balance. The volume is given by the change in weight divided by the density of water. This technique was compared with the more conventional technique of immersing an object in a container with an overflow spout and collecting and weighing the volume of overflow water. The hand volume of two subjects was measured. Hand volumes were 494 +/- 6 ml and 312 +/- 7 ml for the immersion method and 476 +/- 14 ml and 302 +/- 8 ml for the overflow method for the two subjects respectively. Using plastic test objects, the mean difference between the actual and measured volume was -0.3% and 2.0% for the immersion and overflow techniques respectively. This study shows that hand volumes can be obtained more quickly than the overflow method. The technique could find an application in clinics where frequent hand volumes are required.

  2. Comprehensive and Highly Accurate Measurements of Crane Runways, Profiles and Fastenings.

    Science.gov (United States)

    Dennig, Dirk; Bureick, Johannes; Link, Johannes; Diener, Dmitri; Hesse, Christian; Neumann, Ingo

    2017-05-13

    The process of surveying crane runways has been continually refined due to the competitive situation, modern surveying instruments, additional sensors, accessories and evaluation procedures. Guidelines, such as the International Organization for Standardization (ISO) 12488-1, define target values that must be determined by survey. For a crane runway these are for example the span, the position and height of the rails. The process has to be objective and reproducible. However, common processes of surveying crane runways do not meet these requirements sufficiently. The evaluation of the protocols, ideally by an expert, requires many years of experience. Additionally, the recording of crucial parameters, e.g., the wear of the rail, or the condition of the rail fastening and rail joints, is not regulated and for that reason are often not considered during the measurement. To solve this deficit the Advanced Rail Track Inspection System (ARTIS) was developed. ARTIS is used to measure the 3D position of crane rails, the cross-section of the crane rails, joints and, for the first time, the (crane-rail) fastenings. The system consists of a monitoring vehicle and an external tracking sensor. It makes kinematic observations with the tracking sensor from outside the rail run, e.g., the floor of an overhead crane runway, possible. In this paper we present stages of the development process of ARTIS, new target values, calibration of sensors and results of a test measurement.

  3. A Robust Method of Vehicle Stability Accurate Measurement Using GPS and INS

    Directory of Open Access Journals (Sweden)

    Miao Zhibin

    2015-12-01

    Full Text Available With the development of the vehicle industry, controlling stability has become more and more important. Techniques of evaluating vehicle stability are in high demand. Integration of Global Positioning System (GPS and Inertial Navigation System (INS is a very practical method to get high-precision measurement data. Usually, the Kalman filter is used to fuse the data from GPS and INS. In this paper, a robust method is used to measure vehicle sideslip angle and yaw rate, which are two important parameters for vehicle stability. First, a four-wheel vehicle dynamic model is introduced, based on sideslip angle and yaw rate. Second, a double level Kalman filter is established to fuse the data from Global Positioning System and Inertial Navigation System. Then, this method is simulated on a sample vehicle, using Carsim software to test the sideslip angle and yaw rate. Finally, a real experiment is made to verify the advantage of this approach. The experimental results showed the merits of this method of measurement and estimation, and the approach can meet the design requirements of the vehicle stability controller.

  4. Accurate wavelength prediction of photonic crystal resonant reflection and applications in refractive index measurement

    DEFF Research Database (Denmark)

    Hermannsson, Pétur Gordon; Vannahme, Christoph; Smith, Cameron L. C.

    2014-01-01

    and superstrate materials. The importance of accounting for material dispersion in order to obtain accurate simulation results is highlighted, and a method for doing so using an iterative approach is demonstrated. Furthermore, an application for the model is demonstrated, in which the material dispersion......In the past decade, photonic crystal resonant reflectors have been increasingly used as the basis for label-free biochemical assays in lab-on-a-chip applications. In both designing and interpreting experimental results, an accurate model describing the optical behavior of such structures...... is essential. Here, an analytical method for precisely predicting the absolute positions of resonantly reflected wavelengths is presented. The model is experimentally verified to be highly accurate using nanoreplicated, polymer-based photonic crystal grating reflectors with varying grating periods...

  5. Challenges associated with drunk driving measurement: combining police and self-reported data to estimate an accurate prevalence in Brazil.

    Science.gov (United States)

    Sousa, Tanara; Lunnen, Jeffrey C; Gonçalves, Veralice; Schmitz, Aurinez; Pasa, Graciela; Bastos, Tamires; Sripad, Pooja; Chandran, Aruna; Pechansky, Flavio

    2013-12-01

    Drunk driving is an important risk factor for road traffic crashes, injuries and deaths. After June 2008, all drivers in Brazil were subject to a "Zero Tolerance Law" with a set breath alcohol concentration of 0.1 mg/L of air. However, a loophole in this law enabled drivers to refuse breath or blood alcohol testing as it may self-incriminate. The reported prevalence of drunk driving is therefore likely a gross underestimate in many cities. To compare the prevalence of drunk driving gathered from police reports to the prevalence gathered from self-reported questionnaires administered at police sobriety roadblocks in two Brazilian capital cities, and to estimate a more accurate prevalence of drunk driving utilizing three correction techniques based upon information from those questionnaires. In August 2011 and January-February 2012, researchers from the Centre for Drug and Alcohol Research at the Universidade Federal do Rio Grande do Sul administered a roadside interview on drunk driving practices to 805 voluntary participants in the Brazilian capital cities of Palmas and Teresina. Three techniques which include measures such as the number of persons reporting alcohol consumption in the last six hours but who had refused breath testing were used to estimate the prevalence of drunk driving. The prevalence of persons testing positive for alcohol on their breath was 8.8% and 5.0% in Palmas and Teresina respectively. Utilizing a correction technique we calculated that a more accurate prevalence in these sites may be as high as 28.2% and 28.7%. In both cities, about 60% of drivers who self-reported having drank within six hours of being stopped by the police either refused to perform breathalyser testing; fled the sobriety roadblock; or were not offered the test, compared to about 30% of drivers that said they had not been drinking. Despite the reduction of the legal limit for drunk driving stipulated by the "Zero Tolerance Law," loopholes in the legislation permit many

  6. Activity assays and immunoassays for plasma Renin and prorenin: information provided and precautions necessary for accurate measurement

    DEFF Research Database (Denmark)

    Campbell, Duncan J; Nussberger, Juerg; Stowasser, Michael

    2009-01-01

    into focus the differences in information provided by activity assays and immunoassays for renin and prorenin measurement and has drawn attention to the need for precautions to ensure their accurate measurement. CONTENT: Renin activity assays and immunoassays provide related but different information...... provided by these assays and of the precautions necessary to ensure their accuracy....

  7. Standardization of vitrinite reflectance measurements in shale petroleum systems: How accurate are my Ro data?

    Science.gov (United States)

    Hackley, Paul C.

    2014-01-01

    Vitrinite reflectance generally is considered the most robust thermal maturity parameter available for application to hydrocarbon exploration and petroleum system evaluation. However, until 2011 there was no standardized methodology available to provide guidelines for vitrinite reflectance measurements in shale. Efforts to correct this deficiency resulted in publication of ASTM D7708-11: Standard test method for microscopical determination of the reflectance of vitrinite dispersed in sedimentary rocks. In 2012-2013, an interlaboratory exercise was conducted to establish precision limits for the measurement technique. Six samples, representing a wide variety of shale, were tested in duplicate by 28 analysts in 22 laboratories from 14 countries. Samples ranged from immature to overmature (Ro 0.31-1.53%), from organic-rich to organic-lean (1-22 wt.% total organic carbon), and contained Type I (lacustrine), Type II (marine), and Type III (terrestrial) kerogens. Repeatability values (difference between repetitive results from same operator, same conditions) ranged from 0.03-0.11% absolute reflectance, whereas reproducibility values (difference between results obtained on same test material by different operators, different laboratories) ranged from 0.12-0.54% absolute reflectance. Repeatability and reproducibility degraded consistently with increasing maturity and decreasing organic content. However, samples with terrestrial kerogens (Type III) fell off this trend, showing improved levels of reproducibility due to higher vitrinite content and improved ease of identification. Operators did not consistently meet the reporting requirements of the test method, indicating that a common reporting template is required to improve data quality. The most difficult problem encountered was the petrographic distinction of solid bitumens and low-reflecting inert macerals from vitrinite when vitrinite occurred with reflectance ranges overlapping the other components. Discussion among

  8. Spot urine sodium measurements do not accurately estimate dietary sodium intake in chronic kidney disease12

    Science.gov (United States)

    Dougher, Carly E; Rifkin, Dena E; Anderson, Cheryl AM; Smits, Gerard; Persky, Martha S; Block, Geoffrey A; Ix, Joachim H

    2016-01-01

    Background: Sodium intake influences blood pressure and proteinuria, yet the impact on long-term outcomes is uncertain in chronic kidney disease (CKD). Accurate assessment is essential for clinical and public policy recommendations, but few large-scale studies use 24-h urine collections. Recent studies that used spot urine sodium and associated estimating equations suggest that they may provide a suitable alternative, but their accuracy in patients with CKD is unknown. Objective: We compared the accuracy of 4 equations [the Nerbass, INTERSALT (International Cooperative Study on Salt, Other Factors, and Blood Pressure), Tanaka, and Kawasaki equations] that use spot urine sodium to estimate 24-h sodium excretion in patients with moderate to advanced CKD. Design: We evaluated the accuracy of spot urine sodium to predict mean 24-h urine sodium excretion over 9 mo in 129 participants with stage 3–4 CKD. Spot morning urine sodium was used in 4 estimating equations. Bias, precision, and accuracy were assessed and compared across each equation. Results: The mean age of the participants was 67 y, 52% were female, and the mean estimated glomerular filtration rate was 31 ± 9 mL · min–1 · 1.73 m–2. The mean ± SD number of 24-h urine collections was 3.5 ± 0.8/participant, and the mean 24-h sodium excretion was 168.2 ± 67.5 mmol/d. Although the Tanaka equation demonstrated the least bias (mean: −8.2 mmol/d), all 4 equations had poor precision and accuracy. The INTERSALT equation demonstrated the highest accuracy but derived an estimate only within 30% of mean measured sodium excretion in only 57% of observations. Bland-Altman plots revealed systematic bias with the Nerbass, INTERSALT, and Tanaka equations, underestimating sodium excretion when intake was high. Conclusion: These findings do not support the use of spot urine specimens to estimate dietary sodium intake in patients with CKD and research studies enriched with patients with CKD. The parent data for this

  9. A test for ordinal measurement invariance

    NARCIS (Netherlands)

    Ligtvoet, R.; Millsap, R.E.; Bolt, D.M.; van der Ark, L.A.; Wang, W.-C.

    2015-01-01

    One problem with the analysis of measurement invariance is the reliance of the analysis on having a parametric model that accurately describes the data. In this paper an ordinal version of the property of measurement invariance is proposed, which relies only on nonparametric restrictions. This

  10. Describing and compensating gas transport dynamics for accurate instantaneous emission measurement

    Science.gov (United States)

    Weilenmann, Martin; Soltic, Patrik; Ajtay, Delia

    Instantaneous emission measurements on chassis dynamometers and engine test benches are becoming increasingly usual for car-makers and for environmental emission factor measurement and calculation, since much more information about the formation conditions can be extracted than from the regulated bag measurements (integral values). The common exhaust gas analysers for the "regulated pollutants" (carbon monoxide, total hydrocarbons, nitrogen oxide, carbon dioxide) allow measurement at a rate of one to ten samples per second. This gives the impression of having after-the-catalyst emission information with that chronological precision. It has been shown in recent years, however, that beside the reaction time of the analysers, the dynamics of gas transport in both the exhaust system of the car and the measurement system last significantly longer than 1 s. This paper focuses on the compensation of all these dynamics convoluting the emission signals. Most analysers show linear and time-invariant reaction dynamics. Transport dynamics can basically be split into two phenomena: a pure time delay accounting for the transport of the gas downstream and a dynamic signal deformation since the gas is mixed by turbulence along the way. This causes emission peaks to occur which are smaller in height and longer in time at the sensors than they are after the catalyst. These dynamics can be modelled using differential equations. Both mixing dynamics and time delay are constant for modelling a raw gas analyser system, since the flow in that system is constant. In the exhaust system of the car, however, the parameters depend on the exhaust volume flow. For gasoline cars, the variation in overall transport time may be more than 6 s. It is shown in this paper how all these processes can be described by invertible mathematical models with the focus on the more complex case of the car's exhaust system. Inversion means that the sharp emission signal at the catalyst out location can be

  11. In-situ measurements of material thermal parameters for accurate LED lamp thermal modelling

    NARCIS (Netherlands)

    Vellvehi, M.; Perpina, X.; Jorda, X.; Werkhoven, R.J.; Kunen, J.M.G.; Jakovenko, J.; Bancken, P.; Bolt, P.J.

    2013-01-01

    This work deals with the extraction of key thermal parameters for accurate thermal modelling of LED lamps: air exchange coefficient around the lamp, emissivity and thermal conductivity of all lamp parts. As a case study, an 8W retrofit lamp is presented. To assess simulation results, temperature is

  12. On-Line Self-Calibrating Single Crystal Sapphire Optical Sensor Instrumentation for Accurate and Reliable Coal Gasifier Temperature Measurement

    Energy Technology Data Exchange (ETDEWEB)

    Kristie Cooper; Gary Pickrell; Anbo Wang

    2005-11-01

    This report summarizes technical progress April-September 2005 on the Phase II program ''On-Line Self-Calibrating Single Crystal Sapphire Optical Sensor Instrumentation for Accurate and Reliable Coal Gasifier Temperature Measurement'', funded by the Federal Energy Technology Center of the U.S. Department of Energy, and performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech. The outcome of the first phase of this program was the selection of broadband polarimetric differential interferometry (BPDI) for further prototype instrumentation development. This approach is based on the measurement of the optical path difference (OPD) between two orthogonally polarized light beams in a single-crystal sapphire disk. The objective of this program is to bring the sensor technology, which has already been demonstrated in the laboratory, to a level where the sensor can be deployed in the harsh industrial environments and will become commercially viable. Due to the difficulties described on the last report, field testing of the BPDI system has not continued to date. However, we have developed an alternative high temperature sensing solution, which is described in this report. The sensing system will be installed and tested at TECO's Polk Power Station. Following a site visit in June 2005, our efforts have been focused on preparing for that field test, including he design of the sensor mechanical packaging, sensor electronics, the data transfer module, and the necessary software codes to accommodate this application.. We are currently ready to start sensor fabrication.

  13. Unprecedentedly Accurate X-Ray Mass Determination for Several Clusters Using Measured Temperature Profiles

    Science.gov (United States)

    Markevitch, Maxim

    1998-01-01

    We use accurate ASCA gas temperature profiles for nearby clusters A3571, A496, A2199 and some others to derive their mass profiles out to radii of overdensity approximately 500. These are relaxed, moderate cooling flow clusters whose two-dimensional temperature maps do not exhibit any structure that would suggest merging activity. Thus the hydrostatic equilibrium assumption should hold for these clusters and meaningful masses can be derived.

  14. A portable generic elementary function package in Ada and an accurate test suite

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Ping Tak Peter.

    1990-11-01

    A comprehensive set of elementary functions has been implemented portably in Ada. The high accuracy of the implementation has been confirmed by rigorous analysis. Moreover, we present new test methods that are efficient and offer a high resolution of 0.005 unit in the last place. These test methods have been implemented portably here and confirm the accuracy of our implemented functions. Reports on the accuracy of other function libraries obtained by our test programs are also presented. 26 refs., 9 tabs.

  15. Measurements of accurate x-ray scattering data of protein solutions using small stationary sample cells

    Science.gov (United States)

    Hong, Xinguo; Hao, Quan

    2009-01-01

    In this paper, we report a method of precise in situ x-ray scattering measurements on protein solutions using small stationary sample cells. Although reduction in the radiation damage induced by intense synchrotron radiation sources is indispensable for the correct interpretation of scattering data, there is still a lack of effective methods to overcome radiation-induced aggregation and extract scattering profiles free from chemical or structural damage. It is found that radiation-induced aggregation mainly begins on the surface of the sample cell and grows along the beam path; the diameter of the damaged region is comparable to the x-ray beam size. Radiation-induced aggregation can be effectively avoided by using a two-dimensional scan (2D mode), with an interval as small as 1.5 times the beam size, at low temperature (e.g., 4 °C). A radiation sensitive protein, bovine hemoglobin, was used to test the method. A standard deviation of less than 5% in the small angle region was observed from a series of nine spectra recorded in 2D mode, in contrast to the intensity variation seen using the conventional stationary technique, which can exceed 100%. Wide-angle x-ray scattering data were collected at a standard macromolecular diffraction station using the same data collection protocol and showed a good signal/noise ratio (better than the reported data on the same protein using a flow cell). The results indicate that this method is an effective approach for obtaining precise measurements of protein solution scattering.

  16. Measurements of accurate x-ray scattering data of protein solutions using small stationary sample cells

    International Nuclear Information System (INIS)

    Hong Xinguo; Hao Quan

    2009-01-01

    In this paper, we report a method of precise in situ x-ray scattering measurements on protein solutions using small stationary sample cells. Although reduction in the radiation damage induced by intense synchrotron radiation sources is indispensable for the correct interpretation of scattering data, there is still a lack of effective methods to overcome radiation-induced aggregation and extract scattering profiles free from chemical or structural damage. It is found that radiation-induced aggregation mainly begins on the surface of the sample cell and grows along the beam path; the diameter of the damaged region is comparable to the x-ray beam size. Radiation-induced aggregation can be effectively avoided by using a two-dimensional scan (2D mode), with an interval as small as 1.5 times the beam size, at low temperature (e.g., 4 deg. C). A radiation sensitive protein, bovine hemoglobin, was used to test the method. A standard deviation of less than 5% in the small angle region was observed from a series of nine spectra recorded in 2D mode, in contrast to the intensity variation seen using the conventional stationary technique, which can exceed 100%. Wide-angle x-ray scattering data were collected at a standard macromolecular diffraction station using the same data collection protocol and showed a good signal/noise ratio (better than the reported data on the same protein using a flow cell). The results indicate that this method is an effective approach for obtaining precise measurements of protein solution scattering.

  17. The HIT study: Hymenoptera Identification Test--how accurate are people at identifying stinging insects?

    Science.gov (United States)

    Baker, Troy W; Forester, Joseph P; Johnson, Monica L; Stolfi, Adrienne; Stahl, Mark C

    2014-09-01

    Stinging insects in the order Hymenoptera include bees, wasps, yellow jackets, hornets, and ants. Hymenoptera sting injuries range from localized swelling to rarely death. Insect identification is helpful in the management of sting injuries. To determine the accuracy of adults in identifying stinging insects and 2 insect nests. This was a cross-sectional, multicenter study using a picture-based survey to evaluate an individual's success at identifying honeybees, wasps, bald-face hornets, and yellow jackets. Bald-face hornet and paper wasp nest identification also was assessed in this study. Six hundred forty participants completed the questionnaire. Overall, the mean number of correct responses was 3.2 (SD 1.3) of 6. Twenty participants (3.1%) correctly identified all 6 stinging insects and nests and only 10 (1.6%) were unable to identify any of the pictures correctly. The honeybee was the most accurately identified insect (91.3%) and the paper wasp was the least correctly identified insect (50.9%). For the 6 questions regarding whether the participant had been stung in the past by any of the insects (including an unidentified insect), 91% reported being stung by at least 1. Men were more successful at identify stinging insects correctly (P = .002), as were participants stung by at least 4 insects (P = .018). This study supports the general perception that adults are poor discriminators in distinguishing stinging insects and nests with the exception of the honeybee. Men and those participants who reported multiple stings to at least 4 insects were more accurate overall in insect identification. Copyright © 2014 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  18. Strain measurement based battery testing

    Science.gov (United States)

    Xu, Jeff Qiang; Steiber, Joe; Wall, Craig M.; Smith, Robert; Ng, Cheuk

    2017-05-23

    A method and system for strain-based estimation of the state of health of a battery, from an initial state to an aged state, is provided. A strain gauge is applied to the battery. A first strain measurement is performed on the battery, using the strain gauge, at a selected charge capacity of the battery and at the initial state of the battery. A second strain measurement is performed on the battery, using the strain gauge, at the selected charge capacity of the battery and at the aged state of the battery. The capacity degradation of the battery is estimated as the difference between the first and second strain measurements divided by the first strain measurement.

  19. Automated design of paralogue ratio test assays for the accurate and rapid typing of copy number variation

    Science.gov (United States)

    Veal, Colin D.; Xu, Hang; Reekie, Katherine; Free, Robert; Hardwick, Robert J.; McVey, David; Brookes, Anthony J.; Hollox, Edward J.; Talbot, Christopher J.

    2013-01-01

    Motivation: Genomic copy number variation (CNV) can influence susceptibility to common diseases. High-throughput measurement of gene copy number on large numbers of samples is a challenging, yet critical, stage in confirming observations from sequencing or array Comparative Genome Hybridization (CGH). The paralogue ratio test (PRT) is a simple, cost-effective method of accurately determining copy number by quantifying the amplification ratio between a target and reference amplicon. PRT has been successfully applied to several studies analyzing common CNV. However, its use has not been widespread because of difficulties in assay design. Results: We present PRTPrimer (www.prtprimer.org) software for automated PRT assay design. In addition to stand-alone software, the web site includes a database of pre-designed assays for the human genome at an average spacing of 6 kb and a web interface for custom assay design. Other reference genomes can also be analyzed through local installation of the software. The usefulness of PRTPrimer was tested within known CNV, and showed reproducible quantification. This software and database provide assays that can rapidly genotype CNV, cost-effectively, on a large number of samples and will enable the widespread adoption of PRT. Availability: PRTPrimer is available in two forms: a Perl script (version 5.14 and higher) that can be run from the command line on Linux systems and as a service on the PRTPrimer web site (www.prtprimer.org). Contact: cjt14@le.ac.uk Supplementary Information: Supplementary data are available at Bioinformatics online. PMID:23742985

  20. EVALUATION OF OPPORTUNITIES OF SOLAR ENERGETICS ON THE BASIS OF ACCURATE GROUND-BASED MEASUREMENTS OF SOLAR RADIATION

    Directory of Open Access Journals (Sweden)

    Aculinin A.

    2008-04-01

    Full Text Available Expected quantity of a solar energy received by solar panel is estimated on the basis of accurate measurements of solar radiation in Kishinev. Optimal orientation of solar panels and apparent volume of the electric power generated by solar panels are determined.

  1. An accurate measurement of the baryonic Tully-Fisher relation with heavily gas-dominated ALFALFA galaxies

    NARCIS (Netherlands)

    Papastergis, E.; Adams, E. A. K.; van der Hulst, J. M.

    2016-01-01

    We use a sample of 97 galaxies selected from the Arecibo legacy fast ALFA (ALFALFA) 21 cm survey to make an accurate measurement of the baryonic Tully-Fisher relation (BTFR). These galaxies are specifically selected to be heavily gas-dominated (Mgas/M∗ ≳ 2.7) and to be oriented edge-on. The former

  2. Test for Sensitive Detection and Accurate Assignment of TP53 Variants in Tumor DNA

    National Research Council Canada - National Science Library

    Telmer, Cheryl A

    2005-01-01

    .... Preliminary Peptide Mass Signature Genotyping (PMSG) results using bacterial cultures indicated tremendous potential and proof of concept experiments demonstrated that the PMSG process could be converted to an in vitro test...

  3. Pendulum Test: A Highly Accurate and Simple Physical Examination Maneuver to Identify Hip Pathology

    Directory of Open Access Journals (Sweden)

    Yasushi Oshima

    2015-10-01

    Full Text Available Background: Patients with hip pathology often complain of various symptoms, e.g. pain or discomfort of low back, lower extremity, hip, groin, thigh, buttock or knee. Physicians may be distracted by these complaints, and misdiagnose and mistreat hip pathology. To avoid this, the pendulum test, which is performed with a patient seated on the examination table and hips and knees are flexed at 90 degrees, while the examiner passively swings the patient's lower extremity in and out as a pendulum, has been employed for all patients with the complaint of low back, hip and knee. Objective: The efficacy and the accuracy of the pendulum test were evaluated. Patients and methods: Consecutive 40 patients, who had complained pain or discomfort of low back, lower extremity, hip, groin, thigh, buttock and knee were examined by the pendulum test. Results: Eighteen patients were positive for the pendulum test, and all of them correlated to the hip pathology. Conclusions: The pendulum test was confirmed to be easily performed and reliable in detecting the hip pathology. Therefore, this test is highly recommended for the differentiation of patients with low back, hip and knee complaints.

  4. Accurate Monitoring and Fault Detection in Wind Measuring Devices through Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Komal Saifullah Khan

    2014-11-01

    Full Text Available Many wind energy projects report poor performance as low as 60% of the predicted performance. The reason for this is poor resource assessment and the use of new untested technologies and systems in remote locations. Predictions about the potential of an area for wind energy projects (through simulated models may vary from the actual potential of the area. Hence, introducing accurate site assessment techniques will lead to accurate predictions of energy production from a particular area. We solve this problem by installing a Wireless Sensor Network (WSN to periodically analyze the data from anemometers installed in that area. After comparative analysis of the acquired data, the anemometers transmit their readings through a WSN to the sink node for analysis. The sink node uses an iterative algorithm which sequentially detects any faulty anemometer and passes the details of the fault to the central system or main station. We apply the proposed technique in simulation as well as in practical implementation and study its accuracy by comparing the simulation results with experimental results to analyze the variation in the results obtained from both simulation model and implemented model. Simulation results show that the algorithm indicates faulty anemometers with high accuracy and low false alarm rate when as many as 25% of the anemometers become faulty. Experimental analysis shows that anemometers incorporating this solution are better assessed and performance level of implemented projects is increased above 86% of the simulated models.

  5. Supervised oral HIV self-testing is accurate in rural KwaZulu-Natal, South Africa.

    Science.gov (United States)

    Martínez Pérez, Guillermo; Steele, Sarah J; Govender, Indira; Arellano, Gemma; Mkwamba, Alec; Hadebe, Menzi; van Cutsem, Gilles

    2016-06-01

    To achieve UNAIDS 90-90-90 targets, alternatives to conventional HIV testing models are necessary in South Africa to increase population awareness of their HIV status. One of the alternatives is oral mucosal transudates-based HIV self-testing (OralST). This study describes implementation of counsellor-introduced supervised OralST in a high HIV prevalent rural area. Cross-sectional study conducted in two government-run primary healthcare clinics and three Médecins Sans Frontières-run fixed-testing sites in uMlalazi municipality, KwaZulu-Natal. Lay counsellors sampled and recruited eligible participants, sought informed consent and demonstrated the use of the OraQuick(™) OralST. The participants used the OraQuick(™) in front of the counsellor and underwent a blood-based Determine(™) and a Unigold(™) rapid diagnostic test as gold standard for comparison. Primary outcomes were user error rates, inter-rater agreement, sensitivity, specificity and predictive values. A total of 2198 participants used the OraQuick(™) , of which 1005 were recruited at the primary healthcare clinics. Of the total, 1457 (66.3%) were women. Only two participants had to repeat their OraQuick(™) . Inter-rater agreement was 99.8% (Kappa 0.9925). Sensitivity for the OralST was 98.7% (95% CI 96.8-99.6), and specificity was 100% (95% CI 99.8-100). This study demonstrates high inter-rater agreement, and high accuracy of supervised OralST. OralST has the potential to increase uptake of HIV testing and could be offered at clinics and community testing sites in rural South Africa. Further research is necessary on the potential of unsupervised OralST to increase HIV status awareness and linkage to care. © 2016 John Wiley & Sons Ltd.

  6. An accurate measurement of the baryonic Tully-Fisher relation with heavily gas-dominated ALFALFA galaxies

    Science.gov (United States)

    Papastergis, E.; Adams, E. A. K.; van der Hulst, J. M.

    2016-09-01

    We use a sample of 97 galaxies selected from the Arecibo legacy fast ALFA (ALFALFA) 21 cm survey to make an accurate measurement of the baryonic Tully-Fisher relation (BTFR). These galaxies are specifically selected to be heavily gas-dominated (Mgas/M∗ ≳ 2.7) and to be oriented edge-on. The former property ensures that the error on the galactic baryonic mass is small, despite the large systematic uncertainty involved in galactic stellar mass estimates. The latter property means that rotational velocities can be derived directly from the width of the 21 cm emission line, without any need for inclination corrections. We measure a slope for the linewidth-based BTFR of α = 3.75 ± 0.11, a value that is somewhat steeper than (but in broad agreement with) previous literature results. The relation is remarkably tight, with almost all galaxies being located within a perpendicular distance of ± 0.1 dex from the best fit line. The low observational error budget for our sample enables us to establish that, despite its tightness, the measured linewidth-based BTFR has some small (I.e., non-zero) intrinsic scatter. We furthermore find a systematic difference in the BTFR of galaxies with "double-horned" 21 cm line profiles - suggestive of flat outer galactic rotation curves - and those with "peaked" profiles - suggestive of rising rotation curves. When we restrict our sample of galaxies to objects in the former category, we measure a slightly steeper slope of α = 4.13 ± 0.15. Overall, the high-accuracy measurement of the BTFR presented in this article is intended as a reliable observational benchmark against which to test theoretical expectations. Here we consider a representative set of semi-analytic models and hydrodynamic simulations in the lambda cold dark matter (ΛCDM) context, as well as modified Newtonian dynamics (MOND). In the near future, interferometric follow-up observations of several sample members will enable us to further refine the BTFR measurement, and

  7. Fast and Accurate Non-destructive Testing System for Inspection of Canning Tubes

    DEFF Research Database (Denmark)

    Gundtoft, Hans Erik; Nielsen, E.

    1973-01-01

    The authors describe the development of an inspection bench for the non-destructive examination of canning tubes. The bench is original in that the internal diameter is calculated from exact measurement of the outer diameter and the wall thickness. The transducers for inspection and control are r...

  8. General measure of Enterprising Tendency test

    OpenAIRE

    Caird, Sally

    2013-01-01

    The General measure of Enterprising Tendency test (GET2) is a measure of enterprising tendency developed for educational use and self assessment. It measures five entrepreneurial attributes, namely Need for achievement, Need for Autonomy, Creative Tendency, Calculated Risk taking and Locus of control, providing interpretation for this enterprising attributes. Since 1998 there has been considerable worldwide interest in the test of General Enterprising Tendency (GET test) developed and tested ...

  9. A More Accurate Measurement of the {sup 28}Si Lattice Parameter

    Energy Technology Data Exchange (ETDEWEB)

    Massa, E., E-mail: e.massa@inrim.it; Sasso, C. P.; Mana, G. [INRIM—Istituto Nazionale di Ricerca Metrologica, Str. delle Cacce 91, 10135 Torino (Italy); Palmisano, C. [Dipartimento di Fisica, UNITO—Università di Torino, v. P. Giuria 1, 10125 Torino (Italy)

    2015-09-15

    In 2011, a discrepancy between the values of the Planck constant measured by counting Si atoms and by comparing mechanical and electrical powers prompted a review, among others, of the measurement of the spacing of {sup 28}Si (220) lattice planes, either to confirm the measured value and its uncertainty or to identify errors. This exercise confirmed the result of the previous measurement and yields the additional value d{sub 220} = 192 014 711.98(34) am having a reduced uncertainty.

  10. Testing a measure of cyberloafing.

    Science.gov (United States)

    Blau, Gary; Yang, Yang; Ward-Cook, Kory

    2006-01-01

    Using a primary sample of medical technologists (MTs) and a second validation sample, the results of this study showed initial support for a three-factor measure of cyberloafing. The three scales were labeled browsing-related, non-work-related e-mail, and interactive cyberloafing. MTs who perceived unfair treatment in their organization (i.e., lower organizational justice) were more likely to exhibit all three types of cyberloafing. MTs who did not care as much about punctuality and attendance (i.e., higher time abuse) were more likely to display browsing-related and non-work-related e-mail cyberloafing. Finally, MTs who perceived an inability to control their work environment (i.e., powerlessness) were more likely to display interactive cyberloafing. Study limitations and suggestions for future research are discussed.

  11. Surface EMG measurements during fMRI at 3T : Accurate EMG recordings after artifact correction

    NARCIS (Netherlands)

    van Duinen, Hiske; Zijdewind, Inge; Hoogduin, H; Maurits, N

    2005-01-01

    In this experiment, we have measured surface EMG of the first dorsal interosseus during predefined submaximal isometric contractions (5, 15, 30, 50, and 70% of maximal force) of the index finger simultaneously with fMRI measurements. Since we have used sparse sampling fMRI (3-s scanning; 2-s

  12. Method of accurate thickness measurement of boron carbide coating on copper foil

    Science.gov (United States)

    Lacy, Jeffrey L.; Regmi, Murari

    2017-11-07

    A method is disclosed of measuring the thickness of a thin coating on a substrate comprising dissolving the coating and substrate in a reagent and using the post-dissolution concentration of the coating in the reagent to calculate an effective thickness of the coating. The preferred method includes measuring non-conducting films on flexible and rough substrates, but other kinds of thin films can be measure by matching a reliable film-substrate dissolution technique. One preferred method includes determining the thickness of Boron Carbide films deposited on copper foil. The preferred method uses a standard technique known as inductively coupled plasma optical emission spectroscopy (ICPOES) to measure boron concentration in a liquid sample prepared by dissolving boron carbide films and the Copper substrates, preferably using a chemical etch known as ceric ammonium nitrate (CAN). Measured boron concentration values can then be calculated.

  13. Measuring system with stereoscopic x-ray television for accurate diagnosis

    International Nuclear Information System (INIS)

    Iwasaki, K.; Shimizu, S.

    1987-01-01

    X-ray stereoscopic television is diagnostically effective. The authors invented a measuring system using stereoscopic television whereby the coordinates of any two points and their separation can be measured in real time without physical contact. For this purpose, the distances between the two foci of the tube and between the tube and image intensifier were entered into a microcomputer beforehand, and any two points on the CRT stereoscopic image can be defined through the stereoscopic spectacles. The coordinates and distance are then displayed on the CRT monitor. By this means, measurements such as distance between vessels and size of organs are easily made

  14. Can we measure the halo mass of the Milky Way accurately?

    Science.gov (United States)

    Han, Jiaxin; Wang, Wenting; Cole, Shaun; Frenk, Carlos

    2018-01-01

    The halo mass of the Milky Way is considered fundamental in the cosmological interpretation of Galactic observations. A large family of MW mass measurements rely on steady-state modelling of the tracer dynamics. We demonstrate that such measurements can be biased due to unnecessary and unjustified assumptions about the distribution function of tracers. To avoid such biases, we develop a first-principle method that involves minimal assumptions. Applying this method to a large sample of simulated haloes, we show that stars in galactic haloes are not in a steady-state, leading to a systematic uncertainty up to a factor of three in the halo mass measurement.

  15. Supporting Accurate Interpretation of Self-Administered Medical Test Results for Mobile Health: Assessment of Design, Demographics, and Health Condition.

    Science.gov (United States)

    Hohenstein, Jess C; Baumer, Eric Ps; Reynolds, Lindsay; Murnane, Elizabeth L; O'Dell, Dakota; Lee, Seoho; Guha, Shion; Qi, Yu; Rieger, Erin; Gay, Geri

    2018-02-28

    Technological advances in personal informatics allow people to track their own health in a variety of ways, representing a dramatic change in individuals' control of their own wellness. However, research regarding patient interpretation of traditional medical tests highlights the risks in making complex medical data available to a general audience. This study aimed to explore how people interpret medical test results, examined in the context of a mobile blood testing system developed to enable self-care and health management. In a preliminary investigation and main study, we presented 27 and 303 adults, respectively, with hypothetical results from several blood tests via one of the several mobile interface designs: a number representing the raw measurement of the tested biomarker, natural language text indicating whether the biomarker's level was low or high, or a one-dimensional chart illustrating this level along a low-healthy axis. We measured respondents' correctness in evaluating these results and their confidence in their interpretations. Participants also told us about any follow-up actions they would take based on the result and how they envisioned, generally, using our proposed personal health system. We find that a majority of participants (242/328, 73.8%) were accurate in their interpretations of their diagnostic results. However, 135 of 328 participants (41.1%) expressed uncertainty and confusion about their ability to correctly interpret these results. We also find that demographics and interface design can impact interpretation accuracy, including false confidence, which we define as a respondent having above average confidence despite interpreting a result inaccurately. Specifically, participants who saw a natural language design were the least likely (421.47 times, P=.02) to exhibit false confidence, and women who saw a graph design were less likely (8.67 times, P=.04) to have false confidence. On the other hand, false confidence was more likely

  16. Very accurate upward continuation to low heights in a test of non-Newtonian theory

    Science.gov (United States)

    Romaides, Anestis J.; Jekeli, Christopher

    1989-01-01

    Recently, gravity measurements were made on a tall, very stable television transmitting tower in order to detect a non-Newtonian gravitational force. This experiment required the upward continuation of gravity from the Earth's surface to points as high as only 600 m above ground. The upward continuation was based on a set of gravity anomalies in the vicinity of the tower whose data distribution exhibits essential circular symmetry and appropriate radial attenuation. Two methods were applied to perform the upward continuation - least-squares solution of a local harmonic expansion and least-squares collocation. Both methods yield comparable results, and have estimated accuracies on the order of 50 microGal or better (1 microGal = 10(exp -8) m/sq s). This order of accuracy is commensurate with the tower gravity measurments (which have an estimated accuracy of 20 microGal), and enabled a definitive detection of non-Newtonian gravity. As expected, such precise upward continuations require very dense data near the tower. Less expected was the requirement of data (though sparse) up to 220 km away from the tower (in the case that only an ellipsoidal reference gravity is applied).

  17. Accurate on-chip measurement of the Seebeck coefficient of high mobility small molecule organic semiconductors

    Directory of Open Access Journals (Sweden)

    C. N. Warwick

    2015-09-01

    Full Text Available We present measurements of the Seebeck coefficient in two high mobility organic small molecules, 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT and 2,9-didecyl-dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (C10-DNTT. The measurements are performed in a field effect transistor structure with high field effect mobilities of approximately 3 cm2/V s. This allows us to observe both the charge concentration and temperature dependence of the Seebeck coefficient. We find a strong logarithmic dependence upon charge concentration and a temperature dependence within the measurement uncertainty. Despite performing the measurements on highly polycrystalline evaporated films, we see an agreement in the Seebeck coefficient with modelled values from Shi et al. [Chem. Mater. 26, 2669 (2014] at high charge concentrations. We attribute deviations from the model at lower charge concentrations to charge trapping.

  18. Accurate evaluation of viscoelasticity of radial artery wall during flow-mediated dilation in ultrasound measurement

    Science.gov (United States)

    Sakai, Yasumasa; Taki, Hirofumi; Kanai, Hiroshi

    2016-07-01

    In our previous study, the viscoelasticity of the radial artery wall was estimated to diagnose endothelial dysfunction using a high-frequency (22 MHz) ultrasound device. In the present study, we employed a commercial ultrasound device (7.5 MHz) and estimated the viscoelasticity using arterial pressure and diameter, both of which were measured at the same position. In a phantom experiment, the proposed method successfully estimated the elasticity and viscosity of the phantom with errors of 1.8 and 30.3%, respectively. In an in vivo measurement, the transient change in the viscoelasticity was measured for three healthy subjects during flow-mediated dilation (FMD). The proposed method revealed the softening of the arterial wall originating from the FMD reaction within 100 s after avascularization. These results indicate the high performance of the proposed method in evaluating vascular endothelial function just after avascularization, where the function is difficult to be estimated by a conventional FMD measurement.

  19. Hardware and software for tachistoscopy: how to make accurate measurements on any PC utilizing the Microsoft Windows operating system.

    Science.gov (United States)

    McKinney, C J; MacCormac, E R; Welsh-Bohmer, K A

    1999-02-01

    Methods for automated stimulus display and accurate response time measurement with IBM-compatible PCs are of great importance in cognitive research designs. Accurate measurements of reaction times are required to interpolate other measures, such as speed of mental processing. We present a description of hardware and software that displays stimulus images and performs reaction timing that is not dependent on PC performance characteristics. This is accomplished by electronically bypassing timing errors normally inherent to the operation of the computer. A high-precision external timer measures the time between stimulus onset and a subject's push-button response while a video blanking circuit controls the video presented to the monitor screen. Two options for accurately detecting stimulus onset are presented: (1) A photodetector can be used to sense the actual onset of the stimulus on a secondary video monitor screen; (2) the video blanking circuit can provide a signal coincident with the initiation of video to the monitor. Both methods result in a system timing accuracy of 100 microseconds.

  20. Fast and Accurate Measurement of Entropy Profiles of Commercial Lithium-Ion Cells

    International Nuclear Information System (INIS)

    Osswald, Patrick J.; Rosario, Manuel del; Garche, Jürgen; Jossen, Andreas; Hoster, Harry E.

    2015-01-01

    We report on an effective approach to speed up the measurement of thermodynamic characterization curves (entropy of reaction Δ r S(x)) of rechargeable batteries, in particular commercial 18650 lithium ion cells. We propose and demonstrate a measurement and data processing protocol that reduces the time required to record entropy profiles from time scales of weeks to time scales of hours – without loss in accuracy. For time consuming studies such as investigations on ageing of battery cells, entropy profile measurements thus become as feasible as conventional electrochemical characterisation techniques like dV/dQ or cyclic voltammetry. We demonstrate this at the examples of two ageing protocols applied to a commercial high power and a commercial high energy cell, respectively: (i) accelerated calendric aging by storing cells at 100% state of charge at 60 °C and (ii) continuous cycling with a 1C current at 25 °C

  1. Accurate measurement of nanoparticle charge, number and size with the ELPI+{sup TM} instrument

    Energy Technology Data Exchange (ETDEWEB)

    Lamminen, Erkki, E-mail: erkki.lamminen@dekati.fi [Osuusmyllynkatu 13, 33700 Tampere (Finland)

    2011-07-06

    Nanoparticle characterization is mainly carried out by microscopy techniques and measurements of size and concentration. However to be able to comprehensively understand the behavior of the aerosol, information on particle charge level is critical. Particle charge has a major effect on the coagulation, deposition and transport as well as on the health effects of the particles. While aged aerosols generally are mainly neutral in terms of charge, freshly generated or resuspended particles can have high charge levels that vary depending on the size, material and generation method of the particles. Charging processes for particles are problematic as they are usually both time dependent and material dependent with sudden changes in magnitude. This makes the charge of a particle nearly impossible to predict without detailed studies and direct measurements. ELPI+{sup TM} instrument is a completely new aerosol measurement instrument based on the widely used Electrical Low Pressure Impactor (ELPI) technique. ELPI+{sup TM} measures particle concentration and size in a wide size range from 6nm to 10{mu}m in real-time. The operation is based on first charging the particles in a corona charger and then size segregating them in a cascade impactor where all impactor stages are electrically insulated. With the ELPI+{sup TM} instrument it is possible to measure not only the particle size and concentration in real-time, but also the charge distribution of the particles. As the particle size classification is made with an impactor, the measured particles can be subsequently analyzed if needed with a suitable technique.

  2. Accurate measurement of the transition dipole moment of self-assembled quantum dots

    DEFF Research Database (Denmark)

    Stobbe, Søren; Johansen, Jeppe; Nikolaev, I.S.

    2007-01-01

    Here we present quantitative measurements of the dipole moment of an ensemble of self-assembled quantum dots employing a modified optical local density of states (LDOS). The LDOS is controlled by varying the distance from the QDs to a semiconductor/air interface.......Here we present quantitative measurements of the dipole moment of an ensemble of self-assembled quantum dots employing a modified optical local density of states (LDOS). The LDOS is controlled by varying the distance from the QDs to a semiconductor/air interface....

  3. Analysis of plant galactolipids by reversed-phase high-performance liquid chromatography/mass spectrometry with accurate mass measurement

    Czech Academy of Sciences Publication Activity Database

    Zábranská, Marie; Vrkoslav, Vladimír; Sobotníková, J.; Cvačka, Josef

    2012-01-01

    Roč. 165, č. 5 (2012), s. 601-607 ISSN 0009-3084 R&D Projects: GA ČR GA203/09/0139 Grant - others:GA UK(CZ) SVV 2012-265201 Institutional research plan: CEZ:AV0Z40550506 Keywords : accurate mass measurement * DGDG * equivalent carbon number * MGDG * RP-HPLC/MS Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.147, year: 2012

  4. Validation of the Automated Method VIENA: An Accurate, Precise, and Robust Measure of Ventricular Enlargement

    NARCIS (Netherlands)

    Vrenken, H.; Vos, E.K.; van der Flier, W.M.; Sluimer, I.C.; Cover, K.S.; Knol, D.L.; Barkhof, F.

    2014-01-01

    Background: In many retrospective studies and large clinical trials, high-resolution, good-contrast 3DT1 images are unavailable, hampering detailed analysis of brain atrophy. Ventricular enlargement then provides a sensitive indirect measure of ongoing central brain atrophy. Validated automated

  5. Integrating sphere-based setup as an accurate system for optical properties measurements

    CSIR Research Space (South Africa)

    Abdalmonem, S

    2010-09-01

    Full Text Available Determination of the optical properties of solid and liquid samples has great importance. Since the integrating sphere-based setup is used to measure the amount of reflected and transmitted light by the examined samples, optical properties could...

  6. A technique for accurate measurements of temperature variations in solution calorimetry and osmometry of actinide complexes

    International Nuclear Information System (INIS)

    Ponkshe, M.R.; Samuel, J.K.

    1982-01-01

    The temperature variations of the order of 10 3- to 10 -4 C are measured by means of matched pair of thermistors and constant current techniques. The factors deciding the sensitivity and accuracy are fully discussed. Also the factors which put restrictions on the practical detection limits are also described. (author)

  7. High- and low-pressure pneumotachometers measure respiration rates accurately in adverse environments

    Science.gov (United States)

    Fagot, R. J.; Mc Donald, R. T.; Roman, J. A.

    1968-01-01

    Respiration-rate transducers in the form of pneumotachometers measure respiration rates of pilots operating high performance research aircraft. In each low pressure or high pressure oxygen system a sensor is placed in series with the pilots oxygen supply line to detect gas flow accompanying respiration.

  8. Development and calibration of an accurate 6-degree-of-freedom measurement system with total station

    International Nuclear Information System (INIS)

    Gao, Yang; Lin, Jiarui; Yang, Linghui; Zhu, Jigui

    2016-01-01

    To meet the demand of high-accuracy, long-range and portable use in large-scale metrology for pose measurement, this paper develops a 6-degree-of-freedom (6-DOF) measurement system based on total station by utilizing its advantages of long range and relative high accuracy. The cooperative target sensor, which is mainly composed of a pinhole prism, an industrial lens, a camera and a biaxial inclinometer, is designed to be portable in use. Subsequently, a precise mathematical model is proposed from the input variables observed by total station, imaging system and inclinometer to the output six pose variables. The model must be calibrated in two levels: the intrinsic parameters of imaging system, and the rotation matrix between coordinate systems of the camera and the inclinometer. Then corresponding approaches are presented. For the first level, we introduce a precise two-axis rotary table as a calibration reference. And for the second level, we propose a calibration method by varying the pose of a rigid body with the target sensor and a reference prism on it. Finally, through simulations and various experiments, the feasibilities of the measurement model and calibration methods are validated, and the measurement accuracy of the system is evaluated. (paper)

  9. An affordable and accurate conductivity probe for density measurements in stratified flows

    Science.gov (United States)

    Carminati, Marco; Luzzatto-Fegiz, Paolo

    2015-11-01

    In stratified flow experiments, conductivity (combined with temperature) is often used to measure density. The probes typically used can provide very fine spatial scales, but can be fragile, expensive to replace, and sensitive to environmental noise. A complementary instrument, comprising a low-cost conductivity probe, would prove valuable in a wide range of applications where resolving extremely small spatial scales is not needed. We propose using micro-USB cables as the actual conductivity sensors. By removing the metallic shield from a micro-B connector, 5 gold-plated microelectrodes are exposed and available for 4-wire measurements. These have a cell constant ~550m-1, an intrinsic thermal noise of at most 30pA/Hz1/2, as well as sub-millisecond time response, making them highly suitable for many stratified flow measurements. In addition, we present the design of a custom electronic board (Arduino-based and Matlab-controlled) for simultaneous acquisition from 4 sensors, with resolution (in conductivity, and resulting density) exceeding the performance of typical existing probes. We illustrate the use of our conductivity-measuring system through stratified flow experiments, and describe plans to release simple instructions to construct our complete system for around 200.

  10. Is the tono-pen accurate for measuring intraocular pressure in young children with congenital glaucoma?

    Science.gov (United States)

    Levy, Jaime; Lifshitz, Tova; Rosen, Shirley; Tessler, Zvi; Biedner, Ben-Zion

    2005-08-01

    We sought to compare intraocular pressure (IOP) measurements by Perkins tonometer and Tono-Pen in young children with primary congenital glaucoma (PCG). This was a retrospective comparative case series. We reviewed the clinical records of all children with primary congenital glaucoma who underwent examinations under general anesthesia at Soroka University Medical Center between January 1999 and July 2002. Our main outcome measures were IOP with Perkins hand-held tonometer and Tono-Pen tonometer. A total of 28 eyes of 16 children were examined under general anesthesia. The mean IOP was 18 +/- 6 mm Hg with the Perkins tonometer and 22 +/- 8 mm Hg with the Tono-Pen. In 18 eyes, IOP was less than 21 mm Hg with the Perkins tonometer; these eyes had already undergone surgical procedures. The other 10 eyes with IOP greater than 21 mm Hg with the Perkins tonometer underwent surgery at the end of the examination under anesthesia. In eyes with IOP greater than 16 mm Hg (Group A, n = 18), a significant difference (P < 0.001) was found between the Perkins and Tono-Pen measurements, even although the values were strongly correlated (r = 0.60). In contrast, in eyes with IOP less than 16 mm Hg (Group B, n = 10) no statistically significant difference (P = 0.28) and good correlation (r = 0.78) were obtained. A difference of 5.8 +/- 3.8 mm Hg and 0.6 +/- 1.7 mm Hg between Perkins and Tono-Pen readings, respectively, was found in Groups A and B. Tono-Pen readings disagree with Perkins tonometer measurements for measuring IOP in children with PCG who present with IOP greater than 16 mm Hg and tends to overestimate IOP. A further study with a similar population is necessary to confirm these results.

  11. Fast and Accurate Collocation of the Visible Infrared Imaging Radiometer Suite Measurements with Cross-Track Infrared Sounder

    Directory of Open Access Journals (Sweden)

    Likun Wang

    2016-01-01

    Full Text Available Given the fact that Cross-track Infrared Sounder (CrIS and the Visible Infrared Imaging Radiometer Suite (VIIRS are currently onboard the Suomi National Polar-orbiting Partnership (Suomi NPP satellite and will continue to be carried on the same platform as future Joint Polar Satellite System (JPSS satellites for the next decade, it is desirable to develop a fast and accurate collocation scheme to collocate VIIRS products and measurements with CrIS for applications that rely on combining measurements from two sensors such as inter-calibration, geolocation assessment, and cloud detection. In this study, an accurate and fast collocation method to collocate VIIRS measurements within CrIS instantaneous field of view (IFOV directly based on line-of-sight (LOS pointing vectors is developed and discussed in detail. We demonstrate that this method is not only accurate and precise from a mathematical perspective, but also easy to implement computationally. More importantly, with optimization, this method is very fast and efficient and thus can meet operational requirements. Finally, this collocation method can be extended to a wide variety of sensors on different satellite platforms.

  12. Accurate measurements of solar spectral irradiance between 4000-10000 cm-1

    Science.gov (United States)

    Elsey, J.; Coleman, M. D.; Gardiner, T.; Shine, K. P.

    2017-12-01

    The near-infrared solar spectral irradiance (SSI) is an important input into simulations of weather and climate; the distribution of energy throughout this region of the spectrum influences atmospheric heating rates and the global hydrological cycle through absorption and scattering by water vapour. Current measurements by a mixture of ground-based and space-based instruments show differences of around 10% in the 4000-7000 cm-1 region, with no resolution to this controversy in sight. This work presents observations of SSI taken using a ground-based Fourier Transform spectrometer between 4000-10000 cm-1 at a field site in Camborne, UK, with particular focus on a rigorously defined uncertainty budget. While there is good agreement between this work and the commonly-used ATLAS3 spectrum between 7000-10000 cm-1, the SSI is systematically lower by 10% than ATLAS3 between 4000-7000 cm-1, with no overlap within the k = 2 measurement uncertainties.

  13. Techniques for Accurate Parallax Measurements for 6.7 GHz Methanol Masers

    Energy Technology Data Exchange (ETDEWEB)

    Reid, M. J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Brunthaler, A.; Menten, K. M.; Sanna, A. [Max-Planck-Institut für Radioastronomy, Auf dem Hügel 69, D-53121-Bonn (Germany); Xu, Y.; Sakai, N. [Mizusawa VLBI Observatory, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Li, J. J.; Wu, Y.; Hu, B. [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Zheng, X. W. [Department of Astronomy, Nanjing University, Nanjing 210093 (China); Zhang, B. [Shanghai Astrophysical Observatory, 80 Nandan Road, Shanghai 200030 (China); Immer, K. [European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748, Garching bei München (Germany); Rygl, K. [Italian ALMA Regional Centre, INAF—Istituto di Radioastronomia, Via P. Gobetti 101, I-40129 Bologna (Italy); Moscadelli, L. [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125, Firenze (Italy); Bartkiewicz, A. [Centre for Astronomy, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Torun (Poland); Choi, Y. K. [Korea Astronomy and Space Science Institute 776, Daedeokdae-ro, Yuseong-gu, Daejeon, 34055 (Korea, Republic of)

    2017-08-01

    The BeSSeL Survey is mapping the spiral structure of the Milky Way by measuring trigonometric parallaxes of hundreds of maser sources associated with high-mass star formation. While parallax techniques for water masers at high frequency (22 GHz) have been well documented, recent observations of methanol masers at lower frequency (6.7 GHz) have revealed astrometric issues associated with signal propagation through the ionosphere that could significantly limit parallax accuracy. These problems displayed as a “parallax gradient” on the sky when measured against different background quasars. We present an analysis method in which we generate position data relative to an “artificial quasar” at the target maser position at each epoch. Fitting parallax to these data can significantly mitigate the problems and improve parallax accuracy.

  14. Review of RDC Soft Computing Techniques for Accurate Measurement of Resolver Rotor Angle

    Directory of Open Access Journals (Sweden)

    Chandra Mohan Reddy Sivappagari

    2013-03-01

    Full Text Available A resolver is a position sensor or transducer that measures the instantaneous angular position of the rotating shaft to which it is attached. Resolver produces two amplitude modulated signals; SIN and COS as output signals. These two signals need to be demodulated and converted to digital signals before they can be used for control. There are several techniques available in the literature to measure the rotor shaft angle. This paper focuses on the design of both hardware and software based resolver to digital converter (RDC techniques available in the literature. This literature review helps the researchers to know about all these methods and plan future work on RDCs to improve the angle tracking performance.

  15. Digital Integrator for Fast Accurate Measurement of Magnetic Flux by Rotating Coils

    CERN Document Server

    Arpaia, P.; Spiezia, G.

    2007-01-01

    A fast digital integrator (FDI) with dynamic accuracy and a trigger frequency higher than those of a portable digital integrator (PDI), which is a state-of-the-art instrument for magnetic measurements based on rotating coils, was developed for analyzing superconducting magnets in particle accelerators. Results of static and dynamic metrological characterization show how the FDI prototype is already capable of overcoming the dynamic performance of PDI as well as covering operating regions that used to be inaccessible

  16. Front-end electronics for accurate energy measurement of double beta decays

    International Nuclear Information System (INIS)

    Gil, A.; Díaz, J.; Gómez-Cadenas, J.J.; Herrero, V.; Rodriguez, J.; Serra, L.; Toledo, J.; Esteve, R.; Monzó, J.M.; Monrabal, F.; Yahlali, N.

    2012-01-01

    NEXT, a double beta decay experiment that will operate in Canfranc Underground Laboratory (Spain), aims at measuring the neutrinoless double-β decay of the 136Xe isotope using a TPC filled with enriched Xenon gas at high pressure operated in electroluminescence mode. One technological challenge of the experiment is to achieve resolution better than 1% in the energy measurement using a plane of UV sensitive photomultipliers readout with appropriate custom-made front-end electronics. The front-end is designed to be sensitive to the single photo-electron to detect the weak primary scintillation light produced in the chamber, and also to be able to cope with the electroluminescence signal (several hundred times higher and with a duration of microseconds). For efficient primary scintillation detection and precise energy measurement of the electroluminescent signals the front-end electronics features low noise and adequate amplification. The signal shaping provided allows the digitization of the signals at a frequency as low as 40 MHz.

  17. Regular, Fast and Accurate Airborne In-Situ Methane Measurements Around the Tropopause

    Science.gov (United States)

    Dyroff, Christoph; Rauthe-Schöch, Armin; Schuck, Tanja J.; Zahn, Andreas

    2013-04-01

    We present a laser spectrometer for automated monthly measurements of methane (CH4) mixing ratios aboard the CARIBIC passenger aircraft. The instrument is based on a commercial fast methane analyzer (FMA, Los Gatos Res.), which was modified for fully unattended employment. A laboratory characterization was performed and the results with emphasis on the precision, cross sensitivity to H2O, and accuracy are presented. An in-flight calibration strategy is described, that utilizes CH4 measurements obtained from flask samples taken during the same flights. By statistical comparison of the in-situ measurements with the flask samples we derive a total uncetrainty estimate of ~ 3.85 ppbv (1?) around the tropopause, and ~ 12.4 ppbv (1?) during aircraft ascent and descent. Data from the first two years of airborne operation are presented that span a large part of the northern hemispheric upper troposphere and lowermost stratosphere, with occasional crossings of the tropics on flights to southern Africa. With its high spatial resolution and high accuracy this data set is unprecedented in the highly important atmospheric layer of the tropopause.

  18. Accurate quantitation standards of glutathione via traceable sulfur measurement by inductively coupled plasma optical emission spectrometry and ion chromatography

    Science.gov (United States)

    Rastogi, L.; Dash, K.; Arunachalam, J.

    2013-01-01

    The quantitative analysis of glutathione (GSH) is important in different fields like medicine, biology, and biotechnology. Accurate quantitative measurements of this analyte have been hampered by the lack of well characterized reference standards. The proposed procedure is intended to provide an accurate and definitive method for the quantitation of GSH for reference measurements. Measurement of the stoichiometrically existing sulfur content in purified GSH offers an approach for its quantitation and calibration through an appropriate characterized reference material (CRM) for sulfur would provide a methodology for the certification of GSH quantity, that is traceable to SI (International system of units). The inductively coupled plasma optical emission spectrometry (ICP-OES) approach negates the need for any sample digestion. The sulfur content of the purified GSH is quantitatively converted into sulfate ions by microwave-assisted UV digestion in the presence of hydrogen peroxide prior to ion chromatography (IC) measurements. The measurement of sulfur by ICP-OES and IC (as sulfate) using the “high performance” methodology could be useful for characterizing primary calibration standards and certified reference materials with low uncertainties. The relative expanded uncertainties (% U) expressed at 95% confidence interval for ICP-OES analyses varied from 0.1% to 0.3%, while in the case of IC, they were between 0.2% and 1.2%. The described methods are more suitable for characterizing primary calibration standards and certifying reference materials of GSH, than for routine measurements. PMID:29403814

  19. Validation of measured friction by process tests

    DEFF Research Database (Denmark)

    Eriksen, Morten; Henningsen, Poul; Tan, Xincai

    The objective of sub-task 3.3 is to evaluate under actual process conditions the friction formulations determined by simulative testing. As regards task 3.3 the following tests have been used according to the original project plan: 1. standard ring test and 2. double cup extrusion test. The task...... has, however, been extended to include a number of new developed process tests: 3. forward rod extrusion test, 4. special ring test at low normal pressure, 5. spike test (especially developed for warm and hot forging). Validation of the measured friction values in cold forming from sub-task 3.1 has...

  20. Accurate Measurement of ‘Q’ Factor of An Inductive Coil Using a Modified Maxwell Wein Bridge Network

    Directory of Open Access Journals (Sweden)

    Subrata CHATTOPADHYAY

    2009-06-01

    Full Text Available The Q factor of a coil can be measured by measuring accurately the inductance and effective resistance of the coil for a specific signal. The inductance of an inductive coil is generally measured by usual inductive circuit like Maxwell-Wein Bridge, Hay Bridge etc. which suffer from error due to stray capacitance between bridge nodal point and ground and stray inductance of the inductive coil. The conventional Wagner Earth Technique is not suitable for continuous measurement. In the present paper, a modified operational amplifier based Maxwell-Wein Bridge measurement technique has been proposed in which stray capacitance and stray inductance are minimized. The experiment is done for different value of known inductance & Q factor for a specific signal. The linear characteristic with a good repeatability, linearity and variable sensitivity has been described.

  1. Hydrogen sulfide detection based on reflection: from a poison test approach of ancient China to single-cell accurate localization.

    Science.gov (United States)

    Kong, Hao; Ma, Zhuoran; Wang, Song; Gong, Xiaoyun; Zhang, Sichun; Zhang, Xinrong

    2014-08-05

    With the inspiration of an ancient Chinese poison test approach, we report a rapid hydrogen sulfide detection strategy in specific areas of live cells using silver needles with good spatial resolution of 2 × 2 μm(2). Besides the accurate-localization ability, this reflection-based strategy also has attractive merits of convenience and robust response when free pretreatment and short detection time are concerned. The success of endogenous H2S level evaluation in cellular cytoplasm and nuclear of human A549 cells promises the application potential of our strategy in scientific research and medical diagnosis.

  2. Accurate Mass Measurements for Planetary Microlensing Events Using High Angular Resolution Observations

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Beaulieu

    2018-04-01

    Full Text Available The microlensing technique is a unique method to hunt for cold planets over a range of mass and separation, orbiting all varieties of host stars in the disk of our galaxy. It provides precise mass-ratio and projected separations in units of the Einstein ring radius. In order to obtain the physical parameters (mass, distance, orbital separation of the system, it is necessary to combine the result of light curve modeling with lens mass-distance relations and/or perform a Bayesian analysis with a galactic model. A first mass-distance relation could be obtained from a constraint on the Einstein ring radius if the crossing time of the source over the caustic is measured. It could then be supplemented by secondary constraints such as parallax measurements, ideally by using coinciding ground and space-born observations. These are still subject to degeneracies, like the orbital motion of the lens. A third mass-distance relation can be obtained thanks to constraints on the lens luminosity using high angular resolution observations with 8 m class telescopes or the Hubble Space Telescope. The latter route, although quite inexpensive in telescope time is very effective. If we have to rely heavily on Bayesian analysis and limited constraints on mass-distance relations, the physical parameters are determined to 30–40% typically. In a handful of cases, ground-space parallax is a powerful route to get stronger constraint on masses. High angular resolution observations will be able to constrain the luminosity of the lenses in the majority of the cases, and in favorable circumstances it is possible to derive physical parameters to 10% or better. Moreover, these constraints will be obtained in most of the planets to be discovered by the Euclid and WFIRST satellites. We describe here the state-of-the-art approaches to measure lens masses and distances with an emphasis on high angular resolution observations. We will discuss the challenges, recent results and

  3. Rapid and accurate processing method for amide proton exchange rate measurement in proteins

    International Nuclear Information System (INIS)

    Koskela, Harri; Heikkinen, Outi; Kilpelaeinen, Ilkka; Heikkinen, Sami

    2007-01-01

    Exchange between protein backbone amide hydrogen and water gives relevant information about solvent accessibility and protein secondary structure stability. NMR spectroscopy provides a convenient tool to study these dynamic processes with saturation transfer experiments. Processing of this type of NMR spectra has traditionally required peak integration followed by exponential fitting, which can be tedious with large data sets. We propose here a computer-aided method that applies inverse Laplace transform in the exchange rate measurement. With this approach, the determination of exchange rates can be automated, and reliable results can be acquired rapidly without a need for manual processing

  4. Integration of a silicon-based microprobe into a gear measuring instrument for accurate measurement of micro gears

    International Nuclear Information System (INIS)

    Ferreira, N; Krah, T; Jeong, D C; Kniel, K; Härtig, F; Metz, D; Dietzel, A; Büttgenbach, S

    2014-01-01

    The integration of silicon micro probing systems into conventional gear measuring instruments (GMIs) allows fully automated measurements of external involute micro spur gears of normal modules smaller than 1 mm. This system, based on a silicon microprobe, has been developed and manufactured at the Institute for Microtechnology of the Technische Universität Braunschweig. The microprobe consists of a silicon sensor element and a stylus which is oriented perpendicularly to the sensor. The sensor is fabricated by means of silicon bulk micromachining. Its small dimensions of 6.5 mm × 6.5 mm allow compact mounting in a cartridge to facilitate the integration into a GMI. In this way, tactile measurements of 3D microstructures can be realized. To enable three-dimensional measurements with marginal forces, four Wheatstone bridges are built with diffused piezoresistors on the membrane of the sensor. On the reverse of the membrane, the stylus is glued perpendicularly to the sensor on a boss to transmit the probing forces to the sensor element during measurements. Sphere diameters smaller than 300 µm and shaft lengths of 5 mm as well as measurement forces from 10 µN enable the measurements of 3D microstructures. Such micro probing systems can be integrated into universal coordinate measuring machines and also into GMIs to extend their field of application. Practical measurements were carried out at the Physikalisch-Technische Bundesanstalt by qualifying the microprobes on a calibrated reference sphere to determine their sensitivity and their physical dimensions in volume. Following that, profile and helix measurements were carried out on a gear measurement standard with a module of 1 mm. The comparison of the measurements shows good agreement between the measurement values and the calibrated values. This result is a promising basis for the realization of smaller probe diameters for the tactile measurement of micro gears with smaller modules. (paper)

  5. Individual-Based Allometric Equations Accurately Measure Carbon Storage and Sequestration in Shrublands

    Directory of Open Access Journals (Sweden)

    Norman W.H. Mason

    2014-02-01

    Full Text Available Many studies have quantified uncertainty in forest carbon (C storage estimation, but there is little work examining the degree of uncertainty in shrubland C storage estimates. We used field data to simulate uncertainty in carbon storage estimates from three error sources: (1 allometric biomass equations; (2 measurement errors of shrubs harvested for the allometry; and (3 measurement errors of shrubs in survey plots. We also assessed uncertainty for all possible combinations of these error sources. Allometric uncertainty had the greatest independent effect on C storage estimates for individual plots. The largest error arose when all three error sources were included in simulations (where the 95% confidence interval spanned a range equivalent to 40% of mean C storage. Mean C sequestration (1.73 Mg C ha–1 year–1 exceeded the margin of error produced by the simulated sources of uncertainty. This demonstrates that, even when the major sources of uncertainty were accounted for, we were able to detect relatively modest gains in shrubland C storage.

  6. Accurate measurement of imaging photoplethysmographic signals based camera using weighted average

    Science.gov (United States)

    Pang, Zongguang; Kong, Lingqin; Zhao, Yuejin; Sun, Huijuan; Dong, Liquan; Hui, Mei; Liu, Ming; Liu, Xiaohua; Liu, Lingling; Li, Xiaohui; Li, Rongji

    2018-01-01

    Imaging Photoplethysmography (IPPG) is an emerging technique for the extraction of vital signs of human being using video recordings. IPPG technology with its advantages like non-contact measurement, low cost and easy operation has become one research hot spot in the field of biomedicine. However, the noise disturbance caused by non-microarterial area cannot be removed because of the uneven distribution of micro-arterial, different signal strength of each region, which results in a low signal noise ratio of IPPG signals and low accuracy of heart rate. In this paper, we propose a method of improving the signal noise ratio of camera-based IPPG signals of each sub-region of the face using a weighted average. Firstly, we obtain the region of interest (ROI) of a subject's face based camera. Secondly, each region of interest is tracked and feature-based matched in each frame of the video. Each tracked region of face is divided into 60x60 pixel block. Thirdly, the weights of PPG signal of each sub-region are calculated, based on the signal-to-noise ratio of each sub-region. Finally, we combine the IPPG signal from all the tracked ROI using weighted average. Compared with the existing approaches, the result shows that the proposed method takes modest but significant effects on improvement of signal noise ratio of camera-based PPG estimated and accuracy of heart rate measurement.

  7. Accurate Profile Measurement of the low Intensity Secondary Beams in the CERN Experimental Areas

    CERN Document Server

    AUTHOR|(CDS)2084531; Tranquille, Gerard

    2018-02-23

    The CERN accelerators deliver a wide spectrum of secondary beams to the Experimental Areas. These beams are composed of hadrons, leptons, and heavy ions that can vary greatly in momentum (1 GeV/c to 400 GeV/c) and intensity (10^2 to 10^8 particles per second). The profile, position, and intensity of these beams are measured utilising particle detectors. However, the current systems show several problems that limit the quality of this kind of monitoring. The aim of this doctoral thesis is to investigate the best detector technology that could replace the existing monitors and build a first prototype of it. A review of the existing detection techniques has led to the choice of Scintillating Fibres (SciFi) read-out with Silicon Photomultipliers (SiPM). This detection technology has the potential to perform better in terms of material budget, range of intensities measured, and active area size. In addition, it has particle counting capabilities, which could extend its application to momentum spectrometry or Time...

  8. Cleveland Clinic intelligent mouthguard: a new technology to accurately measure head impact in athletes and soldiers

    Science.gov (United States)

    Bartsch, Adam; Samorezov, Sergey

    2013-05-01

    Nearly 2 million Traumatic Brain Injuries (TBI) occur in the U.S. each year, with societal costs approaching $60 billion. Including mild TBI and concussion, TBI's are prevalent in soldiers returning from Iraq and Afghanistan as well as in domestic athletes. Long-term risks of single and cumulative head impact dosage may present in the form of post traumatic stress disorder (PTSD), depression, suicide, Chronic Traumatic Encephalopathy (CTE), dementia, Alzheimer's and Parkinson's diseases. Quantifying head impact dosage and understanding associated risk factors for the development of long-term sequelae is critical toward developing guidelines for TBI exposure and post-exposure management. The current knowledge gap between head impact exposure and clinical outcomes limits the understanding of underlying TBI mechanisms, including effective treatment protocols and prevention methods for soldiers and athletes. In order to begin addressing this knowledge gap, Cleveland Clinic is developing the "Intelligent Mouthguard" head impact dosimeter. Current testing indicates the Intelligent Mouthguard can quantify linear acceleration with 3% error and angular acceleration with 17% error during impacts ranging from 10g to 174g and 850rad/s2 to 10000rad/s2, respectively. Correlation was high (R2 > 0.99, R2 = 0.98, respectively). Near-term development will be geared towards quantifying head impact dosages in vitro, longitudinally in athletes and to test new sensors for possible improved accuracy and reduced bias. Long-term, the IMG may be useful to soldiers to be paired with neurocognitive clinical data quantifying resultant TBI functional deficits.

  9. Accurate measurement of surface areas of anatomical structures by computer-assisted triangulation of computed tomography images

    Energy Technology Data Exchange (ETDEWEB)

    Allardice, J.T.; Jacomb-Hood, J.; Abulafi, A.M.; Williams, N.S. (Royal London Hospital (United Kingdom)); Cookson, J.; Dykes, E.; Holman, J. (London Hospital Medical College (United Kingdom))

    1993-05-01

    There is a need for accurate surface area measurement of internal anatomical structures in order to define light dosimetry in adjunctive intraoperative photodynamic therapy (AIOPDT). The authors investigated whether computer-assisted triangulation of serial sections generated by computed tomography (CT) scanning can give an accurate assessment of the surface area of the walls of the true pelvis after anterior resection and before colorectal anastomosis. They show that the technique of paper density tessellation is an acceptable method of measuring the surface areas of phantom objects, with a maximum error of 0.5%, and is used as the gold standard. Computer-assisted triangulation of CT images of standard geometric objects and accurately-constructed pelvic phantoms gives a surface area assessment with a maximum error of 2.5% compared with the gold standard. The CT images of 20 patients' pelves have been analysed by computer-assisted triangulation and this shows the surface area of the walls varies from 143 cm[sup 2] to 392 cm[sup 2]. (Author).

  10. Bra band size measurements derived from three-dimensional scans are not accurate in women with large, ptotic breasts.

    Science.gov (United States)

    McGhee, Deirdre E; Ramsay, Lauren G; Coltman, Celeste E; Gho, Sheridan A; Steele, Julie R

    2018-03-01

    This study investigated differences in standard measurements used to determine bra size, under-bust chest circumference (UBCC) and over-bust chest circumference (OBCC), measured from a three-dimensional scan (hand-held scanner) compared to the direct measurement in 111 women (age 21-56 years; right breast volume 57-1672 mL; bra size 10A-18G). Bland-Altman plots of UBCC measurements showed a large positive bias and wide limits of agreement (12 cm; -4.6 to 28 cm), which increased as band size increased but decreased when the breasts were digitally removed from the scan prior to the UBCC measurement. The difference in UBCC measurements determined from scans compared to direct measurement had a strong positive correlation with breast volume and breast ptotis. The OBCC measurements showed a small positive bias (2.4 cm; -3.4 to 8.4), consistent across the range of bra sizes. Bra band size measurements determined from three-dimensional scans can be inaccurate in women with large, ptotic breasts. Practitioner Summary: We investigated potential errors in anthropometric data derived from three-dimensional scans used for bra design and fit. Bra band size measurements taken from three-dimensional scans were over-estimated in women with large breasts, whereas bra cup size measurements were accurate to within one-cup size across the entire range of bra sizes.

  11. Radiochromic Plastic Films for Accurate Measurement of Radiation Absorbed Dose and Dose Distributions

    DEFF Research Database (Denmark)

    McLaughlin, W. L.; Miller, Arne; Fidan, S.

    1977-01-01

    of many polymeric systems in industrial radiation processing. The result is that errors due to energy dependence of response of the radiation sensor are effectively reduced, since the spectral sensitivity of the dose meter matches that of the polymer of interest, over a wide range of photon and electron......Thin radiochromic dye films are useful for measuring large radiation absorbed doses (105–108 rads) and for high-resolution imaging of dose patterns produced by penetrating radiation beams passing through non-homogeneous media. Certain types of amino-substituted triarylmethane cyanides dissolved...... in polymeric solutions can be cast into flexible free-standing thin films of uniform thickness and reproducible response to ultraviolet and ionizing radiation. The increase in optical density versus energy deposited by radiation is linear over a wide range of doses and is for practical purposes independent...

  12. Material interactions with the Low Earth Orbital (LEO) environment: Accurate reaction rate measurements

    Science.gov (United States)

    Visentine, James T.; Leger, Lubert J.

    1987-01-01

    To resolve uncertainties in estimated LEO atomic oxygen fluence and provide reaction product composition data for comparison to data obtained in ground-based simulation laboratories, a flight experiment has been proposed for the space shuttle which utilizes an ion-neutral mass spectrometer to obtain in-situ ambient density measurements and identify reaction products from modeled polymers exposed to the atomic oxygen environment. An overview of this experiment is presented and the methodology of calibrating the flight mass spectrometer in a neutral beam facility prior to its use on the space shuttle is established. The experiment, designated EOIM-3 (Evaluation of Oxygen Interactions with Materials, third series), will provide a reliable materials interaction data base for future spacecraft design and will furnish insight into the basic chemical mechanisms leading to atomic oxygen interactions with surfaces.

  13. Accurate measurement at LEP and SppS and instrumentation for LHC

    International Nuclear Information System (INIS)

    Djama, F.

    2011-01-01

    There are as many chapters in this thesis as periods in my research activities. The first chapter is an introduction to this work, the second chapter deals with the subject of my doctoral thesis presented in 1991 and that was about the determination of the parameters of the hadronic resonance of the Z 0 boson at LEP. The third chapter is dedicated to my first post-doctoral researches at CERN in the team of the UA4/2 experiment. The aim of UA4/2 was to measure the real part of the proton-antiproton elastic scattering for an energy of 541 GeV measured in the center of mass frame. The technique of dispersion relations have been used to predict the total proton-proton or proton-antiproton cross-section at higher energies. The fourth chapter deals with my second post-doctoral job performed at the CRN of Strasbourg: I took part into the development of 3 charged track detectors: the Si microstrip detector, the microstrip gaseous chamber and the diamond microstrip counter. The fifth chapter is dedicated to my contribution to the design of the electromagnetic calorimeter of the ATLAS experiment. In 2005 I joined the team that fabricated the pixel detector for ATLAS and I took part into its implementation and the study of its first data. The improvement of the simulation model will allow us to optimize detector operation and to apprehend its aging due to radiation effects. Ideas for a better simulation are presented in the sixth chapter

  14. A More Accurate Measure of Local Public Goods: Overlapping Government Combinations as Units of Analysis

    Directory of Open Access Journals (Sweden)

    Samuel B. Stone

    2014-01-01

    Full Text Available This study posits and tests the viability of a new unit of analysis for local public goods in metropolitan areas: overlapping government combinations (OGCs. Counties, municipalities, school districts, and other special districts operate simultaneously within the same space, each providing their own set of local public goods. Residents of the same city can live within the boundaries of different counties, school districts and other special districts and thus receive (and pay for very different quantities and qualities of public goods. Though there is a great deal of literature devoted to the variation of local public goods in a fragmented metropolitan region, there is none that cumulates the different local government types into units that represent the true bundles of local public goods that are provided to citizens and property owners. This study tackles this problem through the application of geographic information systems (GIS to stack counties, municipalities, and school districts in the Dallas-Fort Worth-Arlington CMSA into unique OGCs. The unique OGCs are compared to their underlying component governments with respect to property tax rates and school performance and are found to be statistically distinct.

  15. Accurate early infant HIV diagnosis in primary health clinics using a point-of-care nucleic acid test.

    Science.gov (United States)

    Jani, Ilesh V; Meggi, Bindiya; Mabunda, Nédio; Vubil, Adolfo; Sitoe, Nadia E; Tobaiwa, Ocean; Quevedo, Jorge I; Lehe, Jonathan D; Loquiha, Osvaldo; Vojnov, Lara; Peter, Trevor F

    2014-09-01

    To evaluate the accuracy of a point-of-care (POC) nucleic acid-based test (NAT) for early infant HIV diagnosis (EID) in primary health clinics in Mozambique. POC and laboratory NAT EID tests were conducted on matched blood samples collected from 827 HIV-exposed infants younger than 18 months who were enrolled consecutively at 4 periurban primary health clinics and the central hospital in Maputo. Lancet heel draw blood collected by nurses was tested on site for HIV-1/-2 RNA on the Alere HIV NAT POC device and also used to create dried blood spots for later laboratory EID testing on the Roche Cobas Taqman/Ampliprep instrument. Results were used to determine the sensitivity, specificity, and agreement between the POC and laboratory NAT EID tests. The sensitivity and specificity of POC NAT EID testing were 98·5% (95% confidence interval (CI): 91.7 to 99.9, n = 65) and 99·9% (95% CI: 99.3 to 100, n = 762), respectively, compared with laboratory EID tests. Overall agreement was high (Cohen kappa = 0·981; 95% CI: 0.96 to 1.00). Positive (98·5%; 95% CI: 96·3 to 100) and negative 99.9% (95% CI: 99.7 to 100) test agreement was also high. Primary health care nurses accurately performed POC NAT EID testing within primary health care clinics. On-site nucleic acid-based EID testing is technically feasible in clinic settings and could be used in efforts to improve access to pediatric HIV antiretroviral treatment.

  16. Computerized tomography magnified bone windows are superior to standard soft tissue windows for accurate measurement of stone size: an in vitro and clinical study.

    Science.gov (United States)

    Eisner, Brian H; Kambadakone, Avinash; Monga, Manoj; Anderson, James K; Thoreson, Andrew A; Lee, Hang; Dretler, Stephen P; Sahani, Dushyant V

    2009-04-01

    We determined the most accurate method of measuring urinary stones on computerized tomography. For the in vitro portion of the study 24 calculi, including 12 calcium oxalate monohydrate and 12 uric acid stones, that had been previously collected at our clinic were measured manually with hand calipers as the gold standard measurement. The calculi were then embedded into human kidney-sized potatoes and scanned using 64-slice multidetector computerized tomography. Computerized tomography measurements were performed at 4 window settings, including standard soft tissue windows (window width-320 and window length-50), standard bone windows (window width-1120 and window length-300), 5.13x magnified soft tissue windows and 5.13x magnified bone windows. Maximum stone dimensions were recorded. For the in vivo portion of the study 41 patients with distal ureteral stones who underwent noncontrast computerized tomography and subsequently spontaneously passed the stones were analyzed. All analyzed stones were 100% calcium oxalate monohydrate or mixed, calcium based stones. Stones were prospectively collected at the clinic and the largest diameter was measured with digital calipers as the gold standard. This was compared to computerized tomography measurements using 4.0x magnified soft tissue windows and 4.0x magnified bone windows. Statistical comparisons were performed using Pearson's correlation and paired t test. In the in vitro portion of the study the most accurate measurements were obtained using 5.13x magnified bone windows with a mean 0.13 mm difference from caliper measurement (p = 0.6). Measurements performed in the soft tissue window with and without magnification, and in the bone window without magnification were significantly different from hand caliper measurements (mean difference 1.2, 1.9 and 1.4 mm, p = 0.003, window settings with magnification. For uric acid calculi the measurement error was observed only in standard soft tissue window settings. In vivo 4.0x

  17. Physical Model for Rapid and Accurate Determination of Nanopore Size via Conductance Measurement.

    Science.gov (United States)

    Wen, Chenyu; Zhang, Zhen; Zhang, Shi-Li

    2017-10-27

    Nanopores have been explored for various biochemical and nanoparticle analyses, primarily via characterizing the ionic current through the pores. At present, however, size determination for solid-state nanopores is experimentally tedious and theoretically unaccountable. Here, we establish a physical model by introducing an effective transport length, L eff , that measures, for a symmetric nanopore, twice the distance from the center of the nanopore where the electric field is the highest to the point along the nanopore axis where the electric field falls to e -1 of this maximum. By [Formula: see text], a simple expression S 0 = f (G, σ, h, β) is derived to algebraically correlate minimum nanopore cross-section area S 0 to nanopore conductance G, electrolyte conductivity σ, and membrane thickness h with β to denote pore shape that is determined by the pore fabrication technique. The model agrees excellently with experimental results for nanopores in graphene, single-layer MoS 2 , and ultrathin SiN x films. The generality of the model is verified by applying it to micrometer-size pores.

  18. Accurate weak lensing of standard candles. II. Measuring σ8 with supernovae

    Science.gov (United States)

    Quartin, Miguel; Marra, Valerio; Amendola, Luca

    2014-01-01

    Soon the number of type Ia supernova (SN) measurements should exceed 100 000. Understanding the effect of weak lensing by matter structures on the supernova brightness will then be more important than ever. Although SN lensing is usually seen as a source of systematic noise, we will show that it can be in fact turned into signal. More precisely, the non-Gaussianity introduced by lensing in the SN Hubble diagram dispersion depends rather sensitively on the amplitude σ8 of the matter power spectrum. By exploiting this relation, we are able to predict constraints on σ8 of 7% (3%) for a catalog of 100 000 (500 000) SNe of average magnitude error 0.12, without having to assume that such intrinsic dispersion and its redshift evolution are known a priori. The intrinsic dispersion has been assumed to be Gaussian; possible intrinsic non-Gaussianities in the data set (due to the SN themselves and/or to other transients) could be potentially dealt with by means of additional nuisance parameters describing higher moments of the intrinsic dispersion distribution function. This method is independent of and complementary to the standard methods based on cosmic microwave background, cosmic shear, or cluster abundance observables.

  19. The Quick Measure of a Nurbs Surface Curvature for Accurate Triangular Meshing

    Directory of Open Access Journals (Sweden)

    Kniat Aleksander

    2014-04-01

    Full Text Available NURBS surfaces are the most widely used surfaces for three-dimensional models in CAD/ CAE programs. When a model for FEM calculation is prepared with a CAD program it is inevitable to mesh it finally. There are many algorithms for meshing planar regions. Some of them may be used for meshing surfaces but it is necessary to take the curvature of the surface under consideration to avoid poor quality mesh. The mesh must be denser in the curved regions of the surface. In this paper, instead of analysing a surface curvature, the method to assess how close is a mesh triangle to the surface to which its vertices belong, is presented. The distance between a mesh triangle and a parallel tangent plane through a point on a surface is the measure of the triangle quality. Finding the surface point whose projection is located inside the mesh triangle and which is the tangency point to the plane parallel to this triangle is an optimization problem. Mathematical description of the problem and the algorithm to find its solution are also presented in the paper.

  20. PRISM, a Patient-Reported Outcome Instrument, Accurately Measures Symptom Change in Refractory Gastroesophageal Reflux Disease.

    Science.gov (United States)

    Fuller, Garth; Bolus, Roger; Whitman, Cynthia; Talley, Jennifer; Erder, M Haim; Joseph, Alain; Silberg, Debra G; Spiegel, Brennan

    2017-03-01

    Most patients with gastroesophageal reflux disease (GERD) experience relief following treatment with proton pump inhibitors (PPIs) (Vakil et al. in Am J Gastroenterol 101:1900-1920, 2006; Everhart and Ruhl in Gastroenterology 136:376-386, 2009). As many as 17-44% of patients, however, exhibit only partial response to therapy. Most extant GERD patient-reported outcome (PRO) instruments fail to meet development best practices as described by the FDA (Talley and Wiklund in Qual Life Res 14:21-33, 2005; Van Pinxteren et al. in Cochrane Database Syst Rev 18:CD002095, 2004; El-Serag et al. in Aliment Pharmacol Ther 32:720-737, 2010). To develop and validate a PRO instrument for clinical trials involving patients with GERD who are PPI partial responders. We prepared a systematic literature review, held patient focus groups, convened an expert panel, and conducted cognitive interviews to establish content validity. Eligible participants took PPI therapy for at least 8 weeks, had undergone an upper endoscopy, and scored at least 8 points on the GerdQ [6]. Qualitative data guided development of 26 draft items. Items were reviewed by expert panels and debriefed with patients. The resulting 21-item instrument underwent psychometric evaluation during a Phase IIB trial. During the trial, confirmatory factor analysis (n = 220) resulted in a four-factor model displaying the highest goodness of fit. All domains had a high inter-item correlation (Cronbach's α > 0.8). Test-retest reliability and convergent validity were strong, with highly significant (p GERD with a partial response to PPI therapy.

  1. Accurate particle speed prediction by improved particle speed measurement and 3-dimensional particle size and shape characterization technique

    DEFF Research Database (Denmark)

    Cernuschi, Federico; Rothleitner, Christian; Clausen, Sønnik

    2017-01-01

    methods, e.g. laser light scattering, and velocity by the double disk (DD) method. In this article we present two novel techniques, which allow a more accurate measurement of mass, velocity and shape, and we later compare the experimentally obtained flow velocities of particles with a simulation that also...... are compared with detailed 3-dimensional CT measurements and a low angle laser light scattering (LALLS) measurement system for six different samples of particles. It is shown that the particle volume or mass is usually overestimated by 16–22% when using 2-dimensional methods or LALLS. For CT allows...... additionally the surface-equivalent diameter to be calculated by using 2-dimensional projections of each particle, these results can be used to correct particle diameters measured with the particle imaging method using a pulsed LED....

  2. Measurement of children's creativity by tests

    Directory of Open Access Journals (Sweden)

    Maksić Slavica B.

    2003-01-01

    Full Text Available After over a 50-year permanent development of tests designed to measure creativity and the results they produced, a question is raised if creativity can be measured by tests at all. A special problem are procedures for measuring creative potential in younger children because children, unlike adults, do not possess creative products that are a single reliable evidence of creativity in the real world. The paper considers test reliability and validity in measuring creativity as well as the dilemma: how much justifiable it is to measure children's creativity by tests if it is not clear what they measure and if there is not a significant relationship between creativity scores and creativity in life. Unsatisfactory creativity test reliability and validity does not mean those tests should be given up the majority of researchers agree. Of the tests of creativity administered in work with the young, the status of Urban-Jellen Test of Creative Thinking - Drawing Production (TCT-DP is given prominence due to the fact that over the past ten years or so it has been used in a larger number of studies as well as in some studies carried out in this country. In TCT-DP scoring is not based on statistical uncommonness of the figures produced but on a number of criteria derived from Gestalt psychology. The factor analyses of the defined criteria of creativity, applied on samples in various settings yielded that the test contains an essential factor of creativity "novelty".

  3. Rapid, accurate, and simultaneous measurement of water and oil contents in the fried starchy system using low-field NMR.

    Science.gov (United States)

    Chen, Long; Tian, Yaoqi; Sun, Binghua; Wang, Jinpeng; Tong, Qunyi; Jin, Zhengyu

    2017-10-15

    Fried starchy food is rich in oil that may pose a risk to health. For controlling of the oil uptake, a rapid and accurate method for the determination of oil content in the fried starchy food is important. In this study, low-field nuclear magnetic resonance (LF-NMR) was applied to simultaneously determine water and oil contents in the model fried starchy system. The proton signals from oil and water were verified and distinguished by desiccation at 105°C. There was no superposition between oil and water signals in the fried starch, making it possible for quantitative analysis of water and oil in a single test. Compared with Soxhlet extraction, the LF-NMR analysis provided a more accurate result of oil content in the fried starchy system, confirming the practicability of the application of LF-NMR technology as a fast and accurate method for the quantification of water and oil in the fried starchy system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Proteomic Analyses using High-Efficiency Separations and Accurate Mass Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, Jon M.; Smith, Richard D.

    2006-08-01

    can now couple multi-dimensional liquid chromatography (LC) separations with MS analysis. Combined with a ?bottom up? strategy, in which proteins are digested into smaller peptide fragments for identification, the LC-MS platform has proved highly successful for identifying peptides (and generally proteins) from complex samples. This chapter discusses proteome analysis techniques that are based on high resolution LC separations and high mass accuracy MS instrumentation, specifically the use of Fourier transform ion cyclotron resonance MS (FTICR), and their application for high throughput global identification of proteins. The simultaneously expanded sensitivity, dynamic range, and mass accuracy afforded by FTICR place this system at the forefront of analytical systems that can attain proteomic identifications from complex biological samples. We will begin the discussions by describing a high throughput proteomics approach that capitalizes on the attributes of FTICR. The critically important supporting components that combine to provide a comprehensive proteomic analysis capability?electrospray ionization efficiency, pre-MS high efficiency LC separations, and downstream data processing methods?will then be discussed with the intent of providing insight into the process as a whole, as well as to highlight analytical challenges that remain to be addressed. Because quantitative measurements are so important to understanding even the simplest biological systems, some of the quantitation techniques and approaches being developed and applied in our laboratory are also discussed. Several applications are exemplified prior to concluding this chapter.

  5. Accurate quantitation standards of glutathione via traceable sulfur measurement by inductively coupled plasma optical emission spectrometry and ion chromatography

    Directory of Open Access Journals (Sweden)

    L. Rastogi

    2013-06-01

    Full Text Available The quantitative analysis of glutathione (GSH is important in different fields like medicine, biology, and biotechnology. Accurate quantitative measurements of this analyte have been hampered by the lack of well characterized reference standards. The proposed procedure is intended to provide an accurate and definitive method for the quantitation of GSH for reference measurements. Measurement of the stoichiometrically existing sulfur content in purified GSH offers an approach for its quantitation and calibration through an appropriate characterized reference material (CRM for sulfur would provide a methodology for the certification of GSH quantity, that is traceable to SI (International system of units. The inductively coupled plasma optical emission spectrometry (ICP-OES approach negates the need for any sample digestion. The sulfur content of the purified GSH is quantitatively converted into sulfate ions by microwave-assisted UV digestion in the presence of hydrogen peroxide prior to ion chromatography (IC measurements. The measurement of sulfur by ICP-OES and IC (as sulfate using the “high performance” methodology could be useful for characterizing primary calibration standards and certified reference materials with low uncertainties. The relative expanded uncertainties (% U expressed at 95% confidence interval for ICP-OES analyses varied from 0.1% to 0.3%, while in the case of IC, they were between 0.2% and 1.2%. The described methods are more suitable for characterizing primary calibration standards and certifying reference materials of GSH, than for routine measurements. Keywords: Glutathione, High performance methodology, MW-UV photolysis, Measurement uncertainty

  6. A Two-Sinker Densimeter for Accurate Measurements of the Density of Natural Gases at Standard Conditions

    Science.gov (United States)

    Richter, Markus; Kleinrahm, Reiner; Glos, Stefan; Wagner, Wolfgang; Span, Roland; Schley, Peter; Uhrig, Martin

    2010-05-01

    A special reference densimeter has been developed for accurate measurements of densities of natural gases and multicomponent gas mixtures at standard conditions of temperature and pressure ( T s = 273.15 K and p s = 0.101325 MPa). The densimeter covers the range from 0.7 kg · m-3 to 1.3 kg · m-3; the total measurement uncertainty in density is 0.020 % (95 % level of confidence). The measurement principle used is the two-sinker method, which is based on the Archimedes buoyancy principle. The certified calibration laboratory of E.ON Ruhrgas AG, Germany, uses this densimeter to verify the standard densities of certified calibration gases (binary and multicomponent gas mixtures). Moreover, the densimeter is used to determine the compositions of commercially available binary gas mixtures with a small uncertainty of (0.01-0.03) mol%.

  7. Accurate isotopic fission yields of electromagnetically induced fission of 238U measured in inverse kinematics at relativistic energies

    Science.gov (United States)

    Pellereau, E.; Taïeb, J.; Chatillon, A.; Alvarez-Pol, H.; Audouin, L.; Ayyad, Y.; Bélier, G.; Benlliure, J.; Boutoux, G.; Caamaño, M.; Casarejos, E.; Cortina-Gil, D.; Ebran, A.; Farget, F.; Fernández-Domínguez, B.; Gorbinet, T.; Grente, L.; Heinz, A.; Johansson, H.; Jurado, B.; Kelić-Heil, A.; Kurz, N.; Laurent, B.; Martin, J.-F.; Nociforo, C.; Paradela, C.; Pietri, S.; Rodríguez-Sánchez, J. L.; Schmidt, K.-H.; Simon, H.; Tassan-Got, L.; Vargas, J.; Voss, B.; Weick, H.

    2017-05-01

    SOFIA (Studies On Fission with Aladin) is a novel experimental program, dedicated to accurate measurements of fission-fragment isotopic yields. The setup allows us to fully identify, in nuclear charge and mass, both fission fragments in coincidence for the whole fission-fragment range. It was installed at the GSI facility (Darmstadt), to benefit from the relativistic heavy-ion beams available there, and thus to use inverse kinematics. This paper reports on fission yields obtained in electromagnetically induced fission of 238U.

  8. An Accurate Method for Inferring Relatedness in Large Datasets of Unphased Genotypes via an Embedded Likelihood-Ratio Test

    KAUST Repository

    Rodriguez, Jesse M.

    2013-01-01

    Studies that map disease genes rely on accurate annotations that indicate whether individuals in the studied cohorts are related to each other or not. For example, in genome-wide association studies, the cohort members are assumed to be unrelated to one another. Investigators can correct for individuals in a cohort with previously-unknown shared familial descent by detecting genomic segments that are shared between them, which are considered to be identical by descent (IBD). Alternatively, elevated frequencies of IBD segments near a particular locus among affected individuals can be indicative of a disease-associated gene. As genotyping studies grow to use increasingly large sample sizes and meta-analyses begin to include many data sets, accurate and efficient detection of hidden relatedness becomes a challenge. To enable disease-mapping studies of increasingly large cohorts, a fast and accurate method to detect IBD segments is required. We present PARENTE, a novel method for detecting related pairs of individuals and shared haplotypic segments within these pairs. PARENTE is a computationally-efficient method based on an embedded likelihood ratio test. As demonstrated by the results of our simulations, our method exhibits better accuracy than the current state of the art, and can be used for the analysis of large genotyped cohorts. PARENTE\\'s higher accuracy becomes even more significant in more challenging scenarios, such as detecting shorter IBD segments or when an extremely low false-positive rate is required. PARENTE is publicly and freely available at http://parente.stanford.edu/. © 2013 Springer-Verlag.

  9. Cross calibration of the Siemens mMR: easily acquired accurate PET phantom measurements, long term stability and reproducibility

    International Nuclear Information System (INIS)

    Keller, Sune H; Jakoby, Bjorn; Hansen, Adam Espe; Svalling, Susanne; Klausen, Thomas L

    2015-01-01

    We present a quick and easy method to perform quantitatively accurate PET scans of typical water-filled PET plastic shell phantoms on the Siemens mMR PET/MR scanner. We perform regular cross calibrations (Xcals) of our PET scanners, including the Siemens mMR PET/MR, with a Siemens mCT water phantom. We evaluate the mMR cross calibration stability over a 3-year period. Recently, the mMR software (VB20P) offered the option of using predefined μ-maps. We evaluated this option by using either the predefined μ-map of the long mMR water phantom or a system-integrated user defined CT-based μ-map of the mCT water phantom used for Xcal. On 54 cross calibrations that were acquired over 3 years, the mMR on average underestimated the concentration by 16% due to the use of MR-based μ-maps. The mMR produced the narrowest range and lowest standard deviation of the Xcal ratios, implying it and is the most stable of the 6 scanners included in this study over a 3 year period. With correctly segmented μ-maps, the mMR produced Xcal ratios of 1.00-1.02, well within the acceptance range [0.95-1.05]. Measuring the concentration in a centrally placed cylindrical VOI allows for some robustness against misregistration of the μ-maps but it should be no more than a few millimeters in the x-y plane, while the tolerance is larger on the z-axis (when, as always with PET, keeping clear of the axial edges of the FOV). The mMR is the most stable scanner in this study and the mean underestimation is no longer an issue with the easily accessible μ-map, which in all 7 tests resulted in correct Xcal ratios. We will share the user defined μ-map of the mCT phantom and the protocol with interested mMR users.

  10. An accurate Rb density measurement method for a plasma wakefield accelerator experiment using a novel Rb reservoir

    CERN Document Server

    Öz, E.; Muggli, P.

    2016-01-01

    A method to accurately measure the density of Rb vapor is described. We plan on using this method for the Advanced Wakefield (AWAKE)~\\cite{bib:awake} project at CERN , which will be the world's first proton driven plasma wakefield experiment. The method is similar to the hook~\\cite{bib:Hook} method and has been described in great detail in the work by W. Tendell Hill et. al.~\\cite{bib:densitymeter}. In this method a cosine fit is applied to the interferogram to obtain a relative accuracy on the order of $1\\%$ for the vapor density-length product. A single-mode, fiber-based, Mach-Zenhder interferometer will be built and used near the ends of the 10 meter-long AWAKE plasma source to be able to make accurate relative density measurement between these two locations. This can then be used to infer the vapor density gradient along the AWAKE plasma source and also change it to the value desired for the plasma wakefield experiment. Here we describe the plan in detail and show preliminary results obtained using a prot...

  11. Measuring Physical Inactivity: Do Current Measures Provide an Accurate View of “Sedentary” Video Game Time?

    Directory of Open Access Journals (Sweden)

    Simon Fullerton

    2014-01-01

    Full Text Available Background. Measures of screen time are often used to assess sedentary behaviour. Participation in activity-based video games (exergames can contribute to estimates of screen time, as current practices of measuring it do not consider the growing evidence that playing exergames can provide light to moderate levels of physical activity. This study aimed to determine what proportion of time spent playing video games was actually spent playing exergames. Methods. Data were collected via a cross-sectional telephone survey in South Australia. Participants aged 18 years and above (n=2026 were asked about their video game habits, as well as demographic and socioeconomic factors. In cases where children were in the household, the video game habits of a randomly selected child were also questioned. Results. Overall, 31.3% of adults and 79.9% of children spend at least some time playing video games. Of these, 24.1% of adults and 42.1% of children play exergames, with these types of games accounting for a third of all time that adults spend playing video games and nearly 20% of children’s video game time. Conclusions. A substantial proportion of time that would usually be classified as “sedentary” may actually be spent participating in light to moderate physical activity.

  12. Fully automated laboratory and field-portable goniometer used for performing accurate and precise multiangular reflectance measurements

    Science.gov (United States)

    Harms, Justin D.; Bachmann, Charles M.; Ambeau, Brittany L.; Faulring, Jason W.; Ruiz Torres, Andres J.; Badura, Gregory; Myers, Emily

    2017-10-01

    Field-portable goniometers are created for a wide variety of applications. Many of these applications require specific types of instruments and measurement schemes and must operate in challenging environments. Therefore, designs are based on the requirements that are specific to the application. We present a field-portable goniometer that was designed for measuring the hemispherical-conical reflectance factor (HCRF) of various soils and low-growing vegetation in austere coastal and desert environments and biconical reflectance factors in laboratory settings. Unlike some goniometers, this system features a requirement for "target-plane tracking" to ensure that measurements can be collected on sloped surfaces, without compromising angular accuracy. The system also features a second upward-looking spectrometer to measure the spatially dependent incoming illumination, an integrated software package to provide full automation, an automated leveling system to ensure a standard frame of reference, a design that minimizes the obscuration due to self-shading to measure the opposition effect, and the ability to record a digital elevation model of the target region. This fully automated and highly mobile system obtains accurate and precise measurements of HCRF in a wide variety of terrain and in less time than most other systems while not sacrificing consistency or repeatability in laboratory environments.

  13. Phishing IQ Tests Measure Fear, Not Ability

    Science.gov (United States)

    Anandpara, Vivek; Dingman, Andrew; Jakobsson, Markus; Liu, Debin; Roinestad, Heather

    We argue that phishing IQ tests fail to measure susceptibility to phishing attacks. We conducted a study where 40 subjects were asked to answer a selection of questions from existing phishing IQ tests in which we varied the portion (from 25% to 100%) of the questions that corresponded to phishing emails. We did not find any correlation between the actual number of phishing emails and the number of emails that the subjects indicated were phishing. Therefore, the tests did not measure the ability of the subjects. To further confirm this, we exposed all the subjects to existing phishing education after they had taken the test, after which each subject was asked to take a second phishing test, with the same design as the first one, but with different questions. The number of stimuli that were indicated as being phishing in the second test was, again, independent of the actual number of phishing stimuli in the test. However, a substantially larger portion of stimuli was indicated as being phishing in the second test, suggesting that the only measurable effect of the phishing education (from the point of view of the phishing IQ test) was an increased concern—not an increased ability.

  14. Direct friction measurement in draw bead testing

    DEFF Research Database (Denmark)

    Olsson, David Dam; Bay, Niels; Andreasen, Jan Lasson

    2005-01-01

    have been reported in literature. A major drawback in all these studies is that friction is not directly measured, but requires repeated measurements of the drawing force with and without relative sliding between the draw beads and the sheet material. This implies two tests with a fixed draw bead tool......-in piezoelectric torque transducer. This technique results in a very sensitive measurement of friction, which furthermore enables recording of lubricant film breakdown as function of drawing distance. The proposed test is validated in an experimental investigation of the influence of lubricant viscosity...

  15. High-voltage test and measuring techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hauschild, Wolfgang; Lemke, Eberhard

    2014-04-01

    Reflects the unit of both HV testing and measuring technique. Intended as an ''application guide'' for the relevant IEC standards. Refers also to future trends in HV testing and measuring technique. With numerous illustrations. It is the intent of this book to combine high-voltage (HV) engineering with HV testing technique and HV measuring technique. Based on long-term experience gained by the authors as lecturer and researcher as well as member in international organizations, such as IEC and CIGRE, the book will reflect the state of the art as well as the future trends in testing and diagnostics of HV equipment to ensure a reliable generation, transmission and distribution of electrical energy. The book is intended not only for experts but also for students in electrical engineering and high-voltage engineering.

  16. Can endocranial volume be estimated accurately from external skull measurements in great-tailed grackles (Quiscalus mexicanus?

    Directory of Open Access Journals (Sweden)

    Corina J. Logan

    2015-06-01

    Full Text Available There is an increasing need to validate and collect data approximating brain size on individuals in the field to understand what evolutionary factors drive brain size variation within and across species. We investigated whether we could accurately estimate endocranial volume (a proxy for brain size, as measured by computerized tomography (CT scans, using external skull measurements and/or by filling skulls with beads and pouring them out into a graduated cylinder for male and female great-tailed grackles. We found that while females had higher correlations than males, estimations of endocranial volume from external skull measurements or beads did not tightly correlate with CT volumes. We found no accuracy in the ability of external skull measures to predict CT volumes because the prediction intervals for most data points overlapped extensively. We conclude that we are unable to detect individual differences in endocranial volume using external skull measurements. These results emphasize the importance of validating and explicitly quantifying the predictive accuracy of brain size proxies for each species and each sex.

  17. Measuring Software Test Verification for Complex Workpieces based on Virtual Gear Measuring Instrument

    Science.gov (United States)

    Yin, Peili; Wang, Jianhua; Lu, Chunxia

    2017-08-01

    Validity and correctness test verification of the measuring software has been a thorny issue hindering the development of Gear Measuring Instrument (GMI). The main reason is that the software itself is difficult to separate from the rest of the measurement system for independent evaluation. This paper presents a Virtual Gear Measuring Instrument (VGMI) to independently validate the measuring software. The triangular patch model with accurately controlled precision was taken as the virtual workpiece and a universal collision detection model was established. The whole process simulation of workpiece measurement is implemented by VGMI replacing GMI and the measuring software is tested in the proposed virtual environment. Taking involute profile measurement procedure as an example, the validity of the software is evaluated based on the simulation results; meanwhile, experiments using the same measuring software are carried out on the involute master in a GMI. The experiment results indicate a consistency of tooth profile deviation and calibration results, thus verifying the accuracy of gear measuring system which includes the measurement procedures. It is shown that the VGMI presented can be applied in the validation of measuring software, providing a new ideal platform for testing of complex workpiece-measuring software without calibrated artifacts.

  18. Measuring Software Test Verification for Complex Workpieces based on Virtual Gear Measuring Instrument

    Directory of Open Access Journals (Sweden)

    Yin Peili

    2017-08-01

    Full Text Available Validity and correctness test verification of the measuring software has been a thorny issue hindering the development of Gear Measuring Instrument (GMI. The main reason is that the software itself is difficult to separate from the rest of the measurement system for independent evaluation. This paper presents a Virtual Gear Measuring Instrument (VGMI to independently validate the measuring software. The triangular patch model with accurately controlled precision was taken as the virtual workpiece and a universal collision detection model was established. The whole process simulation of workpiece measurement is implemented by VGMI replacing GMI and the measuring software is tested in the proposed virtual environment. Taking involute profile measurement procedure as an example, the validity of the software is evaluated based on the simulation results; meanwhile, experiments using the same measuring software are carried out on the involute master in a GMI. The experiment results indicate a consistency of tooth profile deviation and calibration results, thus verifying the accuracy of gear measuring system which includes the measurement procedures. It is shown that the VGMI presented can be applied in the validation of measuring software, providing a new ideal platform for testing of complex workpiece-measuring software without calibrated artifacts.

  19. Accurate, Fast and Cost-Effective Diagnostic Test for Monosomy 1p36 Using Real-Time Quantitative PCR

    Directory of Open Access Journals (Sweden)

    Pricila da Silva Cunha

    2014-01-01

    Full Text Available Monosomy 1p36 is considered the most common subtelomeric deletion syndrome in humans and it accounts for 0.5–0.7% of all the cases of idiopathic intellectual disability. The molecular diagnosis is often made by microarray-based comparative genomic hybridization (aCGH, which has the drawback of being a high-cost technique. However, patients with classic monosomy 1p36 share some typical clinical characteristics that, together with its common prevalence, justify the development of a less expensive, targeted diagnostic method. In this study, we developed a simple, rapid, and inexpensive real-time quantitative PCR (qPCR assay for targeted diagnosis of monosomy 1p36, easily accessible for low-budget laboratories in developing countries. For this, we have chosen two target genes which are deleted in the majority of patients with monosomy 1p36: PRKCZ and SKI. In total, 39 patients previously diagnosed with monosomy 1p36 by aCGH, fluorescent in situ hybridization (FISH, and/or multiplex ligation-dependent probe amplification (MLPA all tested positive on our qPCR assay. By simultaneously using these two genes we have been able to detect 1p36 deletions with 100% sensitivity and 100% specificity. We conclude that qPCR of PRKCZ and SKI is a fast and accurate diagnostic test for monosomy 1p36, costing less than 10 US dollars in reagent costs.

  20. Improvement of the exponential experiment system for the automatical and accurate measurement of the exponential decay constant

    International Nuclear Information System (INIS)

    Shin, Hee Sung; Jang, Ji Woon; Lee, Yoon Hee; Hwang, Yong Hwa; Kim, Ho Dong

    2004-01-01

    The previous exponential experiment system has been improved for the automatical and accurate axial movement of the neutron source and detector with attaching the automatical control system which consists of a Programmable Logical Controller(PLC) and a stepping motor set. The automatic control program which controls MCA and PLC consistently has been also developed on the basis of GENIE 2000 library. The exponential experiments have been carried out for Kori 1 unit spent fuel assemblies, C14, J14 and G23, and Kori 2 unit spent fuel assembly, J44, using the improved systematical measurement system. As the results, the average exponential decay constants for 4 assemblies are determined to be 0.1302, 0.1267, 0.1247, and 0.1210, respectively, with the application of poisson regression

  1. Electromagnetic calorimeter and accurate measurement with the ATLAS detector of the LHC collider; Calorimetrie electromagnetique et mesures de precision avec le detecteur ATLAS aupres du collisionneur LHC

    Energy Technology Data Exchange (ETDEWEB)

    Pralavorio, P

    2007-06-15

    The main purpose of the ATLAS experiment is the understanding of the underlying mechanisms that drive the breaking of the electro-weak symmetry through the discovery of Higgs bosons. An important element to achieve this aim was the design of an electromagnetic calorimeter able to investigate the decay channels: H {yields} {gamma}{gamma} and H {yields} 4e. The high performance of the calorimeter will allow us to get a better accuracy on the measuring values of W and top masses which is essential to indirectly constrain the mass of the Higgs. In the same way, accurate measurements of top and W properties during the decays of top and tWb vertex will be necessary to question the standard model and to see beyond. The author has been working for 9 years in the ATLAS project, he has been involved in the design, construction, qualification and testing phases of the electromagnetic calorimeter of ATLAS. This document is a detailed presentation of the calorimeter, of its qualification and of its expectations when LHC is operating. This document is organized into 4 chapters: 1) assets and weaknesses of the standard model, 2) the ATLAS experiment, 3) the electromagnetic calorimeter, and 4) accurate measurements with ATLAS. This document presented before an academic board will allow its author to manage research works and particularly to tutor thesis students. (A.C.)

  2. submitter Experimental temperature measurements for the energy amplifier test

    CERN Document Server

    Calero, J; Gallego, E; Gálvez, J; García Tabares, L; González, E; Jaren, J; López, C; Lorente, A; Martínez Val, J M; Oropesa, J; Rubbia, C; Rubio, J A; Saldana, F; Tamarit, J; Vieira, S

    1996-01-01

    A uranium thermometer has been designed and built in order to make local power measurements in the First Energy Amplifier Test (FEAT). Due to the experimental conditions power measurements of tens to hundreds of nW were required, implying a sensitivity in the temperature change measurements of the order of 1 mK. A uranium thermometer accurate enough to match that sensitivity has been built. The thermometer is able to determine the absolute energetic gain obtained in a tiny subcritical uranium assembly exposed to a proton beam of kinetic energies between 600 MeV and 2.75 GeV. In addition, the thermometer measurements have provided information about the spatial power distribution and the shape of the neutron spallation cascade.

  3. Accurate measurements of infinite dilution activity coefficients using gas chromatography with static-wall-coated open-tubular columns.

    Science.gov (United States)

    Xu, Qianqian; Su, Baogen; Luo, Xinyi; Xing, Huabin; Bao, Zongbi; Yang, Qiwei; Yang, Yiwen; Ren, Qilong

    2012-11-06

    Wall-coated open-tubular (WCOT) columns provide higher column efficiency and lower solute interfacial adsorption effect than packed columns. However, previous efforts used to measure the infinite dilution activity coefficient (γ(∞)) via a chromatographic technique have used packed columns, because the low carrier gas flow rate (U) and the small stationary phase amount (n(2)) in WCOT columns raise large errors. By rationally revising the γ(∞)-calculation equation for static-wall-coated open-tubular column, we observed that U and n(2) are not necessarily needed and the resulting error could be reduced, and WCOT column gas chromatography subsequently became a superior method for the accurate γ(∞) determination. In this study, we validate our revised γ(∞)-calculation equation by measuring γ(∞) in an ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate system, in which 55 organic compounds covering a wide range of functional groups were used as probe solutes and their γ(∞) values in the ionic liquid were determined at 40.0, 50.0, and 60.0 °C. Experimental error analysis shows that our revised equation remarkably reduces the error compared to the common γ(∞)-calculation equation. Our data is consistent with previously reported values obtained via other techniques, which further proves the credibility of our revised equation. The accurately determined γ(∞) values can be directly used to calculate the partial molar excess enthalpy, selectivity, and capacity, which will benefit for the rapid screening of solvents (especially ionic liquids) in separation approaches.

  4. Testing for Distortions in Performance Measures

    DEFF Research Database (Denmark)

    Sloof, Randolph; Van Praag, Mirjam

    Distorted performance measures in compensation contracts elicit suboptimal behavioral responses that may even prove to be dysfunctional (gaming). This paper applies the empirical test developed by Courty and Marschke (2008) to detect whether the widely used class of Residual Income based performa......Distorted performance measures in compensation contracts elicit suboptimal behavioral responses that may even prove to be dysfunctional (gaming). This paper applies the empirical test developed by Courty and Marschke (2008) to detect whether the widely used class of Residual Income based...... performance measures —such as Economic Value Added (EVA)— is distorted, leading to unintended agent behavior. The paper uses a difference-in-differences approach to account for changes in economic circumstances and the self-selection of firms using EVA. Our findings indicate that EVA is a distorted...... performance measure that elicits the gaming response....

  5. Accurate measurement of heteronuclear dipolar couplings by phase-alternating R-symmetry (PARS) sequences in magic angle spinning NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Guangjin, E-mail: hou@udel.edu, E-mail: tpolenov@udel.edu; Lu, Xingyu, E-mail: luxingyu@udel.edu, E-mail: lexvega@comcast.net; Vega, Alexander J., E-mail: luxingyu@udel.edu, E-mail: lexvega@comcast.net; Polenova, Tatyana, E-mail: hou@udel.edu, E-mail: tpolenov@udel.edu [Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA and Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, Pennsylvania 15261 (United States)

    2014-09-14

    We report a Phase-Alternating R-Symmetry (PARS) dipolar recoupling scheme for accurate measurement of heteronuclear {sup 1}H-X (X = {sup 13}C, {sup 15}N, {sup 31}P, etc.) dipolar couplings in MAS NMR experiments. It is an improvement of conventional C- and R-symmetry type DIPSHIFT experiments where, in addition to the dipolar interaction, the {sup 1}H CSA interaction persists and thereby introduces considerable errors in the dipolar measurements. In PARS, phase-shifted RN symmetry pulse blocks applied on the {sup 1}H spins combined with π pulses applied on the X spins at the end of each RN block efficiently suppress the effect from {sup 1}H chemical shift anisotropy, while keeping the {sup 1}H-X dipolar couplings intact. Another advantage over conventional DIPSHIFT experiments, which require the signal to be detected in the form of a reduced-intensity Hahn echo, is that the series of π pulses refocuses the X chemical shift and avoids the necessity of echo formation. PARS permits determination of accurate dipolar couplings in a single experiment; it is suitable for a wide range of MAS conditions including both slow and fast MAS frequencies; and it assures dipolar truncation from the remote protons. The performance of PARS is tested on two model systems, [{sup 15}N]-N-acetyl-valine and [U-{sup 13}C,{sup 15}N]-N-formyl-Met-Leu-Phe tripeptide. The application of PARS for site-resolved measurement of accurate {sup 1}H-{sup 15}N dipolar couplings in the context of 3D experiments is presented on U-{sup 13}C,{sup 15}N-enriched dynein light chain protein LC8.

  6. Accurate in situ measurement of near-surface volume dilatation in irradiated silica through capacitance monitoring of cantilever deflection

    International Nuclear Information System (INIS)

    Norris, C.B.; EerNisse, E.P.

    1983-01-01

    Irradiating a solid with short-range particle often induces a net volume change in the range zone which results in a shallow layer of stressed material. Micron-depth volume dilatations in the part-per-million range can be studied using cantilever mounting of a long, thin, metallized specimen, whose stress-induced bending perturbs the capacitance between the cantilever and a small counterelectrode mounted close to the unirradiated face. This approach has been used successfully by many workers for more than 20 yrs. Elsewhere we have reported the construction of a highly sensitive caltilever/capacitor apparatus and its application in the first accurate measurements of ionization dilatation phenomena in fused silica and grown SiO 2 at low-electron energies. In this paper we outline key details of apparatus design and experimental technique for successful cantilever/capacitor work. Many contrasts with the work of Primak and Monahan [Rev. Sci. Instrum. 54, 544 (1983) (preceding paper)] are pointed out. We also highlight previous short-term annealing results which make it clear that the compaction of silica will appear to be significantly less in optical measurements made hours after irradiation than in our cantilever/capacitor measurements made minutes after irradiation

  7. Design and testing of an innovative solar radiation measurement device

    International Nuclear Information System (INIS)

    Badran, Omar; Al-Salaymeh, Ahmed; El-Tous, Yousif; Abdala, Wasfi

    2010-01-01

    After review of studies conducted on the solar radiation measuring systems, a new innovative instrument that would help in measuring the accurate solar radiation on horizontal surfaces has been designed and tested. An advanced instrument with ease of use and high precision that would enable the user to take the readings in terms of solar intensity (W/m 2 ) has been tested. Also, the innovative instrument can record instantaneous readings of the solar intensities as well as the averages value of the solar radiation flux during certain periods of time. The instrument based in its design on being programmed by programmable interfacing controller (PIC). Furthermore, the power supply circuit is fed by the solar energy cells and does not need an external power source.

  8. Testing for Distortions in Performance Measures

    DEFF Research Database (Denmark)

    Sloof, Randolph; Van Praag, Mirjam

    2015-01-01

    Distorted performance measures in compensation contracts elicit suboptimal behavioral responses that may even prove to be dysfunctional (gaming). This paper applies the empirical test developed by Courty and Marschke (Review of Economics and Statistics, 90, 428-441) to detect whether the widely...... used class of residual income-based performance measures-such as economic value added (EVA)-is distorted, leading to unintended agent behavior. The paper uses a difference-in-differences approach to account for changes in economic circumstances and the self-selection of firms using EVA. Our findings...... indicate that EVA is a distorted performance measure that elicits the gaming response....

  9. How Accurate Are Electronic Monitoring Devices? A Laboratory Study Testing Two Devices to Measure Medication Adherence

    Directory of Open Access Journals (Sweden)

    Fabienne Dobbels

    2010-03-01

    Full Text Available In a prospective descriptive laboratory study, 25 Helping Hand™ (HH (10 without and 15 with reminder system and 50 Medication Event Monitoring Systems (MEMS (25 with 18-month and 25 with 2-year battery life were manipulated twice daily following a predefined protocol during 3 consecutive weeks. Accuracy was determined using the fixed manipulation scheme as the reference. Perfect functioning (i.e., total absence of missing registrations and/or overregistrations was observed in 70% of the HH without, 87% of the HH with reminder, 20% MEMS with 18 months, and 100% with 2-year battery life respectively.

  10. Work zone performance measures pilot test.

    Science.gov (United States)

    2011-04-01

    Currently, a well-defined and validated set of metrics to use in monitoring work zone performance do not : exist. This pilot test was conducted to assist state DOTs in identifying what work zone performance : measures can and should be targeted, what...

  11. Are rapid diagnostic tests more accurate in diagnosis of plasmodium falciparum malaria compared to microscopy at rural health centres?

    Directory of Open Access Journals (Sweden)

    Magnussen Pascal

    2010-12-01

    Full Text Available Abstract Background Prompt, accurate diagnosis and treatment with artemisinin combination therapy remains vital to current malaria control. Blood film microscopy the current standard test for diagnosis of malaria has several limitations that necessitate field evaluation of alternative diagnostic methods especially in low income countries of sub-Saharan Africa where malaria is endemic. Methods The accuracy of axillary temperature, health centre (HC microscopy, expert microscopy and a HRP2-based rapid diagnostic test (Paracheck was compared in predicting malaria infection using polymerase chain reaction (PCR as the gold standard. Three hundred patients with a clinical suspicion of malaria based on fever and or history of fever from a low and high transmission setting in Uganda were consecutively enrolled and provided blood samples for all tests. Accuracy of each test was calculated overall with 95% confidence interval and then adjusted for age-groups and level of transmission intensity using a stratified analysis. The endpoints were: sensitivity, specificity, positive predictive value (PPV and negative predictive value (NPV. This study is registered with Clinicaltrials.gov, NCT00565071. Results Of the 300 patients, 88(29.3% had fever, 56(18.7% were positive by HC microscopy, 47(15.7% by expert microscopy, 110(36.7% by Paracheck and 89(29.7% by PCR. The overall sensitivity >90% was only shown by Paracheck 91.0% [95%CI: 83.1-96.0]. The sensitivity of expert microscopy was 46%, similar to HC microscopy. The superior sensitivity of Paracheck compared to microscopy was maintained when data was stratified for transmission intensity and age. The overall specificity rates were: Paracheck 86.3% [95%CI: 80.9-90.6], HC microscopy 93.4% [95%CI: 89.1-96.3] and expert microscopy 97.2% [95%CI: 93.9-98.9]. The NPV >90% was shown by Paracheck 95.8% [95%CI: 91.9-98.2]. The overall PPV was Conclusion The HRP2-based RDT has shown superior sensitivity compared to

  12. Measurements of rope elongation or deflection in impact destructive testing

    Directory of Open Access Journals (Sweden)

    Adam Szade

    2015-01-01

    Full Text Available The computation of energy dissipation in mechanical protective systems and the corresponding determination of their safe use in mine shafts, requires a precise description of their bending and elongation, for instance, in conditions of dynamic, transverse loading induced by the falling of mass. The task aimed to apply a fast parallactic rangefinder and then to mount it on a test stand, which is an original development of the Central Mining Institute's Laboratory of Rope Testing in Katowice. In the solution presented in this paper, the measuring method and equipment in which the parallactic laser rangefinder, provided with a fast converter and recording system, ensures non-contact measurement of elongation, deflection or deformation of the sample (construction during impact loading. The structure of the unit, and metrological parameters are also presented. Additionally, the method of calibration and examples of the application in the impact tests of steel wire ropes are presented. The measurement data obtained will provide a basis for analysis, the prediction of the energy of events and for applying the necessary means to maintain explosion-proofness in the case of destructive damage to mechanical elements in the mine atmosphere. What makes these measurements novel is the application of a fast and accurate laser rangefinder to the non-contact measurement of crucial impact parameters of dynamic events that result in the destruction of the sample. In addition, the method introduces a laser scanning vibrometer with the aim of evaluating the parameters of the samples before and after destruction.

  13. Measuring Cardiac Output during Cardiopulmonary Exercise Testing.

    Science.gov (United States)

    Vignati, Carlo; Cattadori, Gaia

    2017-07-01

    Cardiac output is a key parameter in the assessment of cardiac function, and its measurement is fundamental to the diagnosis, treatment, and prognostic evaluation of all heart diseases. Until recently, cardiac output determination during exercise had been only possible through invasive methods, which were not practical in the clinical setting. Because [Formula: see text]o 2 is cardiac output times arteriovenous content difference, evaluation of cardiac output is usually included in its measurement. Because of the difficulty of directly measuring peak exercise cardiac output, indirect surrogate parameters have been proposed, but with only modest clinical usefulness. Direct measurement of cardiac output can now be made by several noninvasive techniques, such as rebreathing inert gases, impedance cardiology, thoracic bioreactance, estimated continuous cardiac output technology, and transthoracic echocardiography coupled to cardiopulmonary exercise testing, which allow more definitive results and better understanding of the underlying physiopathology.

  14. A new device for simple and accurate urinary pH testing by the Stone-former patient.

    Science.gov (United States)

    Grases, Felix; Rodriguez, Adrian; Berga, Francisco; Costa-Bauza, Antonia; Prieto, Rafael Maria; Burdallo, Isabel; Cadarso, Alfredo; Jimenez-Jorquera, Cecilia; Baldi, Antonio; Garganta, Rosendo

    2014-01-01

    Urinary pH is an important factor linked to renal stone disease and a useful marker in the treatment of urolithiasis. Although the gold standard for measuring urinary pH utilizes a glass electrode and a pH meter, at present dipstick testing is largely used to estimate urinary pH. However, the accuracy and precision of this method may be insufficient for making clinical decisions in patients with lithiasis. The aim of this study is to describe a new device for urinary pH testing. The device includes a pH sensor based on differential measurement of an ISFET-REFET pair. The drawbacks associated with this type of configuration, namely short lifetime and manual fabrication, have been overcome in the prototype. An automatic one point calibration is performed when turning on the system. Two buffer solutions were utilized to determine the intra- and inter-day precision of the device. The pH of 30 fresh human urine samples was measured using a pH-meter, a dipstick and the new electronic device. In some cases, dipstick measurements differed from those of the pH meter by more than 0.40 units, a clinically relevant discrepancy, whereas none of the measurements made with the new electronic device differed from the results of the pH-meter by more than 0.1 pH units. This new electronic device has the possibility to be used by stone-formers to control their urinary pH at home, increasing the tools available for stone prevention and prophylaxis.

  15. Building, testing and validating a set of home-made von Frey filaments: a precise, accurate and cost effective alternative for nociception assessment.

    Science.gov (United States)

    de Sousa, Marcelo Victor Pires; Ferraresi, Cleber; de Magalhães, Ana Carolina; Yoshimura, Elisabeth Mateus; Hamblin, Michael R

    2014-07-30

    A von Frey filament (vFF) is a type of aesthesiometer usually made of nylon perpendicularly held in a base. It can be used in paw withdrawal pain threshold assessment, one of the most popular tests for pain evaluation using animal models. For this test, a set of filaments, each able to exert a different force, is applied to the animal paw, from the weakest to the strongest, until the paw is withdrawn. We made 20 low cost vFF using nylon filaments of different lengths and constant diameter glued perpendicularly to the ends of popsicle sticks. They were calibrated using a laboratory balance scale. Building and calibrating took around 4h and confirmed the theoretical prediction that the force exerted is inversely proportional to the length and directly proportional to the width of the filament. The calibration showed that they were precise and accurate. We analyzed the paw withdrawal threshold assessed with the set of home-made vFF and with a high quality commercial set of 5 monofilaments vFF (Stoelting, Wood Dale, USA) in two groups (n=5) of healthy mice. The home-made vFF precisely and accurately measured the hind paw withdrawal threshold (20.3±0.9 g). The commercial vFF have different diameters while our set has the same diameter avoiding the problem of lower sensitivity to larger diameter filaments. Building a set of vFF is easy, cost effective, and depending on the kind of tests, can increase precision and accuracy of animal nociception evaluation. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. High-voltage test and measuring techniques

    CERN Document Server

    Hauschild, Wolfgang

    2014-01-01

    It is the intent of this book to combine high-voltage (HV) engineering with HV testing technique and HV measuring technique. Based on long-term experience gained by the authors as lecturer and researcher as well as member in international organizations, such as IEC and CIGRE, the book will reflect the state of the art as well as the future trends in testing and diagnostics of HV equipment to ensure a reliable generation, transmission and distribution of electrical energy. The book is intended not only for experts but also for students in electrical engineering and high-voltage engineering.

  17. High-precision topography measurement through accurate in-focus plane detection with hybrid digital holographic microscope and white light interferometer module.

    Science.gov (United States)

    Liżewski, Kamil; Tomczewski, Sławomir; Kozacki, Tomasz; Kostencka, Julianna

    2014-04-10

    High-precision topography measurement of micro-objects using interferometric and holographic techniques can be realized provided that the in-focus plane of an imaging system is very accurately determined. Therefore, in this paper we propose an accurate technique for in-focus plane determination, which is based on coherent and incoherent light. The proposed method consists of two major steps. First, a calibration of the imaging system with an amplitude object is performed with a common autofocusing method using coherent illumination, which allows for accurate localization of the in-focus plane position. In the second step, the position of the detected in-focus plane with respect to the imaging system is measured with white light interferometry. The obtained distance is used to accurately adjust a sample with the precision required for the measurement. The experimental validation of the proposed method is given for measurement of high-numerical-aperture microlenses with subwavelength accuracy.

  18. An Optimized Method for Accurate Fetal Sex Prediction and Sex Chromosome Aneuploidy Detection in Non-Invasive Prenatal Testing.

    Science.gov (United States)

    Wang, Ting; He, Quanze; Li, Haibo; Ding, Jie; Wen, Ping; Zhang, Qin; Xiang, Jingjing; Li, Qiong; Xuan, Liming; Kong, Lingyin; Mao, Yan; Zhu, Yijun; Shen, Jingjing; Liang, Bo; Li, Hong

    2016-01-01

    Massively parallel sequencing (MPS) combined with bioinformatic analysis has been widely applied to detect fetal chromosomal aneuploidies such as trisomy 21, 18, 13 and sex chromosome aneuploidies (SCAs) by sequencing cell-free fetal DNA (cffDNA) from maternal plasma, so-called non-invasive prenatal testing (NIPT). However, many technical challenges, such as dependency on correct fetal sex prediction, large variations of chromosome Y measurement and high sensitivity to random reads mapping, may result in higher false negative rate (FNR) and false positive rate (FPR) in fetal sex prediction as well as in SCAs detection. Here, we developed an optimized method to improve the accuracy of the current method by filtering out randomly mapped reads in six specific regions of the Y chromosome. The method reduces the FNR and FPR of fetal sex prediction from nearly 1% to 0.01% and 0.06%, respectively and works robustly under conditions of low fetal DNA concentration (1%) in testing and simulation of 92 samples. The optimized method was further confirmed by large scale testing (1590 samples), suggesting that it is reliable and robust enough for clinical testing.

  19. An Optimized Method for Accurate Fetal Sex Prediction and Sex Chromosome Aneuploidy Detection in Non-Invasive Prenatal Testing.

    Directory of Open Access Journals (Sweden)

    Ting Wang

    Full Text Available Massively parallel sequencing (MPS combined with bioinformatic analysis has been widely applied to detect fetal chromosomal aneuploidies such as trisomy 21, 18, 13 and sex chromosome aneuploidies (SCAs by sequencing cell-free fetal DNA (cffDNA from maternal plasma, so-called non-invasive prenatal testing (NIPT. However, many technical challenges, such as dependency on correct fetal sex prediction, large variations of chromosome Y measurement and high sensitivity to random reads mapping, may result in higher false negative rate (FNR and false positive rate (FPR in fetal sex prediction as well as in SCAs detection. Here, we developed an optimized method to improve the accuracy of the current method by filtering out randomly mapped reads in six specific regions of the Y chromosome. The method reduces the FNR and FPR of fetal sex prediction from nearly 1% to 0.01% and 0.06%, respectively and works robustly under conditions of low fetal DNA concentration (1% in testing and simulation of 92 samples. The optimized method was further confirmed by large scale testing (1590 samples, suggesting that it is reliable and robust enough for clinical testing.

  20. An Optimized Method for Accurate Fetal Sex Prediction and Sex Chromosome Aneuploidy Detection in Non-Invasive Prenatal Testing

    Science.gov (United States)

    Li, Haibo; Ding, Jie; Wen, Ping; Zhang, Qin; Xiang, Jingjing; Li, Qiong; Xuan, Liming; Kong, Lingyin; Mao, Yan; Zhu, Yijun; Shen, Jingjing; Liang, Bo; Li, Hong

    2016-01-01

    Massively parallel sequencing (MPS) combined with bioinformatic analysis has been widely applied to detect fetal chromosomal aneuploidies such as trisomy 21, 18, 13 and sex chromosome aneuploidies (SCAs) by sequencing cell-free fetal DNA (cffDNA) from maternal plasma, so-called non-invasive prenatal testing (NIPT). However, many technical challenges, such as dependency on correct fetal sex prediction, large variations of chromosome Y measurement and high sensitivity to random reads mapping, may result in higher false negative rate (FNR) and false positive rate (FPR) in fetal sex prediction as well as in SCAs detection. Here, we developed an optimized method to improve the accuracy of the current method by filtering out randomly mapped reads in six specific regions of the Y chromosome. The method reduces the FNR and FPR of fetal sex prediction from nearly 1% to 0.01% and 0.06%, respectively and works robustly under conditions of low fetal DNA concentration (1%) in testing and simulation of 92 samples. The optimized method was further confirmed by large scale testing (1590 samples), suggesting that it is reliable and robust enough for clinical testing. PMID:27441628

  1. Educational Testing as an Accountability Measure

    DEFF Research Database (Denmark)

    Ydesen, Christian

    2013-01-01

    for continued use in contemporary educational settings. Accountability measures and practices serve as a way to govern schools; by analysing the history of accountability as the concept has been practised in the education sphere, the article will discuss both pros and cons of such a methodology, particularly......This article reveals perspectives based on experiences from twentieth-century Danish educational history by outlining contemporary, test-based accountability regime characteristics and their implications for education policy. The article introduces one such characteristic, followed by an empirical...... analysis of the origins and impacts of test-based accountability measures applying both top-down and bottom-up perspectives. These historical perspectives offer the opportunity to gain a fuller understanding of this contemporary accountability concept and its potential, appeal, and implications...

  2. Web-based accurate measurements of carotid lumen diameter and stenosis severity: An ultrasound-based clinical tool for stroke risk assessment during multicenter clinical trials.

    Science.gov (United States)

    Saba, Luca; Banchhor, Sumit K; Londhe, Narendra D; Araki, Tadashi; Laird, John R; Gupta, Ajay; Nicolaides, Andrew; Suri, Jasjit S

    2017-12-01

    This pilot study presents a completely automated, novel, smart, cloud-based, point-of-care system for (a) carotid lumen diameter (LD); (b) stenosis severity index (SSI) and (c) total lumen area (TLA) measurement using B-mode ultrasound. The proposed system was (i) validated against manual reading taken by the Neurologist and (ii) benchmarked against the commercially available system. One hundred patients (73 M/27 F, mean age: 68 ± 11 years), institutional review board approved, written informed consent, consisted of left/right common carotid artery (200 ultrasound scans) were acquired using a 7.5-MHz linear transducer. The measured mean LD for left and right carotids were (in mm): (i) for proposed system (6.49 ± 1.77, 6.66 ± 1.70); and (ii) for manual (6.29 ± 1.79, 6.45 ± 1.63), respectively and coefficient of correlation between cloud-based automated against manual were 0.98 (P cloud-based system was: 1.0. Four statistical tests such as: Two-tailed z-test, Mann-Whitney test, Kolmogorov-Smirnov (KS) and one-way ANOVA were performed to demonstrate consistency and reliability. The proposed system is reliable, accurate, fast, completely automated, anytime-anywhere solution for multi-center clinical trials and routine vascular screening. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Accurate quantification of creatinine in serum by coupling a measurement standard to extractive electrospray ionization mass spectrometry

    Science.gov (United States)

    Huang, Keke; Li, Ming; Li, Hongmei; Li, Mengwan; Jiang, You; Fang, Xiang

    2016-01-01

    Ambient ionization (AI) techniques have been widely used in chemistry, medicine, material science, environmental science, forensic science. AI takes advantage of direct desorption/ionization of chemicals in raw samples under ambient environmental conditions with minimal or no sample preparation. However, its quantitative accuracy is restricted by matrix effects during the ionization process. To improve the quantitative accuracy of AI, a matrix reference material, which is a particular form of measurement standard, was coupled to an AI technique in this study. Consequently the analyte concentration in a complex matrix can be easily quantified with high accuracy. As a demonstration, this novel method was applied for the accurate quantification of creatinine in serum by using extractive electrospray ionization (EESI) mass spectrometry. Over the concentration range investigated (0.166 ~ 1.617 μg/mL), a calibration curve was obtained with a satisfactory linearity (R2 = 0.994), and acceptable relative standard deviations (RSD) of 4.6 ~ 8.0% (n = 6). Finally, the creatinine concentration value of a serum sample was determined to be 36.18 ± 1.08 μg/mL, which is in excellent agreement with the certified value of 35.16 ± 0.39 μg/mL.

  4. Determination of well flat band condition in thin film FDSOI transistors using C-V measurement for accurate parameter extraction

    Science.gov (United States)

    Mohamad, B.; Leroux, C.; Reimbold, G.; Ghibaudo, G.

    2018-01-01

    For advanced gate stacks, effective work function (WFeff) and equivalent oxide thickness (EOT) are fundamental parameters for technology optimization. On FDSOI transistors, and contrary to the bulk technologies, while EOT can still be extracted at strong inversion from the typical gate-to-channel capacitance (Cgc), it is no longer the case for WFeff due to the disappearance of an observable flat band condition on capacitance characteristics. In this work, a new experimental method, the Cbg(VBG) characteristic, is proposed in order to extract the well flat band condition (VFB, W). This characteristic enables an accurate and direct evaluation of WFeff. Moreover, using the previous extraction of the gate oxide (tfox), and buried oxide (tbox) from typical capacitance characteristics (Cgc and Cbc), it allows the extraction of the channel thickness (tch). Furthermore, the measurement of the well flat band condition on Cbg(VBG) characteristics for two different Si and SiGe channel also proves the existence of a dipole at the SiGe/SiO2 interface. article>

  5. HLA-DQ-Gluten Tetramer Blood Test Accurately Identifies Patients With and Without Celiac Disease in Absence of Gluten Consumption.

    Science.gov (United States)

    Sarna, Vikas K; Lundin, Knut E A; Mørkrid, Lars; Qiao, Shuo-Wang; Sollid, Ludvig M; Christophersen, Asbjørn

    2018-03-01

    Celiac disease is characterized by HLA-DQ2/8-restricted responses of CD4+ T cells to cereal gluten proteins. A diagnosis of celiac disease based on serologic and histologic evidence requires patients to be on gluten-containing diets. The growing number of individuals adhering to a gluten-free diet (GFD) without exclusion of celiac disease complicates its detection. HLA-DQ-gluten tetramers can be used to detect gluten-specific T cells in blood of patients with celiac disease, even if they are on a GFD. We investigated whether an HLA-DQ-gluten tetramer-based assay accurately identifies patients with celiac disease. We produced HLA-DQ-gluten tetramers and added them to peripheral blood mononuclear cells isolated from 143 HLA-DQ2.5 + subjects (62 subjects with celiac disease on a GFD, 19 subjects without celiac disease on a GFD [due to self-reported gluten sensitivity], 10 subjects with celiac disease on a gluten-containing diet, and 52 presumed healthy individuals [controls]). T cells that bound HLA-DQ-gluten tetramers were quantified by flow cytometry. Laboratory tests and flow cytometry gating analyses were performed by researchers blinded to sample type, except for samples from subjects with celiac disease on a gluten-containing diet. Test precision analyses were performed using samples from 10 subjects. For the HLA-DQ-gluten tetramer-based assay, we combined flow-cytometry variables in a multiple regression model that identified individuals with celiac disease on a GFD with an area under the receiver operating characteristic curve value of 0.96 (95% confidence interval [CI] 0.89-1.00) vs subjects without celiac disease on a GFD. The assay detected individuals with celiac disease on a gluten-containing diet vs controls with an area under the receiver operating characteristic curve value of 0.95 (95% CI 0.90-1.00). Optimized cutoff values identified subjects with celiac disease on a GFD with 97% sensitivity (95% CI 0.92-1.00) and 95% specificity (95% CI 0

  6. Test Beam Measurements on Picosec Gaseous Detector.

    CERN Document Server

    Sohl, Lukas

    2017-01-01

    In the Picosec project micro pattern gaseous detectors with a time resolution of some ten picoseconds are developed. The detectors are based on Micromegas detectors. With a cherenkov window and a photocathode the time jitter from different position of the primary ionization clusters can be substituted. This reports describes the beam setup and measurements of different Picosec prototypes. A time resolution of under 30 ps has been measured during the test beam. This report gives an overview of my work as a Summer Student. I set up and operated a triple-GEM tracker and a trigger system for the beam. During the beam I measured different prototypes of Picosec detectors and analysed the data.

  7. Heparin removal by ecteola-cellulose pre-treatment enables the use of plasma samples for accurate measurement of anti-Yellow fever virus neutralizing antibodies.

    Science.gov (United States)

    Campi-Azevedo, Ana Carolina; Peruhype-Magalhães, Vanessa; Coelho-Dos-Reis, Jordana Grazziela; Costa-Pereira, Christiane; Yamamura, Anna Yoshida; Lima, Sheila Maria Barbosa de; Simões, Marisol; Campos, Fernanda Magalhães Freire; de Castro Zacche Tonini, Aline; Lemos, Elenice Moreira; Brum, Ricardo Cristiano; de Noronha, Tatiana Guimarães; Freire, Marcos Silva; Maia, Maria de Lourdes Sousa; Camacho, Luiz Antônio Bastos; Rios, Maria; Chancey, Caren; Romano, Alessandro; Domingues, Carla Magda; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis

    2017-09-01

    Technological innovations in vaccinology have recently contributed to bring about novel insights for the vaccine-induced immune response. While the current protocols that use peripheral blood samples may provide abundant data, a range of distinct components of whole blood samples are required and the different anticoagulant systems employed may impair some properties of the biological sample and interfere with functional assays. Although the interference of heparin in functional assays for viral neutralizing antibodies such as the functional plaque-reduction neutralization test (PRNT), considered the gold-standard method to assess and monitor the protective immunity induced by the Yellow fever virus (YFV) vaccine, has been well characterized, the development of pre-analytical treatments is still required for the establishment of optimized protocols. The present study intended to optimize and evaluate the performance of pre-analytical treatment of heparin-collected blood samples with ecteola-cellulose (ECT) to provide accurate measurement of anti-YFV neutralizing antibodies, by PRNT. The study was designed in three steps, including: I. Problem statement; II. Pre-analytical steps; III. Analytical steps. Data confirmed the interference of heparin on PRNT reactivity in a dose-responsive fashion. Distinct sets of conditions for ECT pre-treatment were tested to optimize the heparin removal. The optimized protocol was pre-validated to determine the effectiveness of heparin plasma:ECT treatment to restore the PRNT titers as compared to serum samples. The validation and comparative performance was carried out by using a large range of serum vs heparin plasma:ECT 1:2 paired samples obtained from unvaccinated and 17DD-YFV primary vaccinated subjects. Altogether, the findings support the use of heparin plasma:ECT samples for accurate measurement of anti-YFV neutralizing antibodies. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. A Limited Sampling, Simple, and Useful Method for Determination of Glomerular Filtration Rate in Cats by Using a New Accurate HPLC Method to Measure Iohexol Plasmatic Concentrations

    Directory of Open Access Journals (Sweden)

    Meucci Valentina

    2013-01-01

    Full Text Available Glomerular filtration rate (GFR is still a highly underutilized tool in cats because available methods are not easy to be performed in clinical practice. Iohexol (IOX has been shown to be a useful and reliable marker of GFR both in animals and in humans. The aim of the present study was to develop a rapid and reliable method for measuring IOX in feline plasma and to evaluate the accuracy of limited sampling models to establish a low-cost and clinically suitable GFR test. IOX concentrations were determined by using a new HPLC-UV method. GFR was assessed as plasma clearance of IOX, which was calculated by dividing dose administered by area under the curve of plasmatic concentration versus time (AUC, and indexed to body weight (BW. Correlation and agreement analysis between the GFR values obtained by a seven-point clearance method and the GFR values determined by the application of simplified sample combinations indicated that the 3-blood sample clearance model (5, 30, and 60 min was the best simplified method because it provided an accurate GFR value in only one hour. The reported method is a simple and accurate way of GFR determination, which may be easily used in a clinical setting.

  9. Development of an accurate pH measurement methodology for the pore fluids of low pH cementitious materials

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, M. C.; Garcia Calvo, J. L. [The Spanish National Research Council (CSIC), Madrid (Spain); Walker, C. [Japan Atomic Energy Agency (JAEA), Ibaraki (Japan)] [and others

    2012-08-15

    The main objective of this project has been the development of an agreed set of protocols for the pH measurement of the pore fluid of a low pH cementitious material. Three protocols have been developed (Chapter 2), a reference method, based on pore fluid expression (PFE), and two routine methods with and without filtering, based on Ex Situ Leaching (ESL) procedures. Templates have been designed on which to record details of the pH measurement for the reference (PFE) method (Appendix C) and the routine (ESL) methods without and with filtering (Appendix D). Preliminary protocols were based on a broad review of the literature (Appendix A) and refined through a series of test experiments of the more critical parameters (Appendix B). After definition of the preliminary protocols, two phases of interlaboratory tests were performed. The first phase (Chapter 3) used the same low pH cement paste and enabled the nine participating laboratories to use, become familiar with and to identify any problems/uncertainties in the preliminary protocols. The reported pH values were subjected to a statistical analysis of the (within laboratory) repeatability and (between-laboratory) reproducibility and so provided a reliability test of the preliminary protocols. The second phase (Chapter 4) of interlaboratory tests used four different candidate low pH cementitious materials in the same nine laboratories, which allowed testing, validation and comparison of the reported pH values, which were obtained using the final protocols for the reference (PFE) and routine (ESL) methods by statistical analysis. The proposed final protocols (Chapter 2) have resulted in the reported pH values having low deviation and high reproducibility and repeatability. This will allow confidence in the pH value when selecting a candidate low pH cementitious material to be used in the engineered component of a high-level nuclear waste repository.

  10. Development of an accurate pH measurement methodology for the pore fluids of low pH cementitious materials

    International Nuclear Information System (INIS)

    Alonso, M. C.; Garcia Calvo, J. L.; Walker, C.

    2012-08-01

    The main objective of this project has been the development of an agreed set of protocols for the pH measurement of the pore fluid of a low pH cementitious material. Three protocols have been developed (Chapter 2), a reference method, based on pore fluid expression (PFE), and two routine methods with and without filtering, based on Ex Situ Leaching (ESL) procedures. Templates have been designed on which to record details of the pH measurement for the reference (PFE) method (Appendix C) and the routine (ESL) methods without and with filtering (Appendix D). Preliminary protocols were based on a broad review of the literature (Appendix A) and refined through a series of test experiments of the more critical parameters (Appendix B). After definition of the preliminary protocols, two phases of interlaboratory tests were performed. The first phase (Chapter 3) used the same low pH cement paste and enabled the nine participating laboratories to use, become familiar with and to identify any problems/uncertainties in the preliminary protocols. The reported pH values were subjected to a statistical analysis of the (within laboratory) repeatability and (between-laboratory) reproducibility and so provided a reliability test of the preliminary protocols. The second phase (Chapter 4) of interlaboratory tests used four different candidate low pH cementitious materials in the same nine laboratories, which allowed testing, validation and comparison of the reported pH values, which were obtained using the final protocols for the reference (PFE) and routine (ESL) methods by statistical analysis. The proposed final protocols (Chapter 2) have resulted in the reported pH values having low deviation and high reproducibility and repeatability. This will allow confidence in the pH value when selecting a candidate low pH cementitious material to be used in the engineered component of a high-level nuclear waste repository

  11. A technique for accurately determining the cusp-region polar cap boundary using SuperDARN HF radar measurements

    Directory of Open Access Journals (Sweden)

    G. Chisham

    Full Text Available Accurately measuring the location and motion of the polar cap boundary (PCB in the high-latitude ionosphere can be crucial for studies concerned with the dynamics of the polar cap, e.g. the measurement of reconnection rates. The Doppler spectral width characteristics of backscatter received by the SuperDARN HF radars have been previously used for locating and tracking the PCB in the cusp region. The boundary is generally observed in meridional beams of the SuperDARN radars and appears as a distinct change between low spectral width values observed equatorward of the cusp region, and high, but variable spectral width values observed within the cusp region. To identify the spectral width boundary (SWB between these two regions, a simple algorithm employing a spectral width threshold has often been applied to the data. However, there is not, as yet, a standard algorithm, or spectral width threshold, which is universally applied. Nor has there been any rigorous assessment of the accuracy of this method of boundary determination. This study applies a series of threshold algorithms to a simulated cusp-region spectral width data set, to assess the accuracy of different algorithms. This shows that simple threshold algorithms correctly identify the boundary location in, at the most, 50% of the cases and that the average boundary error is at least ~ 1–2 range gates (~ 1° latitude. It transpires that spatial and temporal smoothing of the spectral width data (e.g. by median filtering, before application of a threshold algorithm can increase the boundary determination accuracy to over 95% and the average boundary error to much less than a range gate. However, this is sometimes at the cost of temporal resolution in the motion of the boundary location. The algorithms are also applied to a year’s worth of spectral width data from the cusp ionosphere, measured by the Halley SuperDARN radar in Antarctica. This analysis highlights the increased accuracy of

  12. A technique for accurately determining the cusp-region polar cap boundary using SuperDARN HF radar measurements

    Directory of Open Access Journals (Sweden)

    G. Chisham

    2003-04-01

    Full Text Available Accurately measuring the location and motion of the polar cap boundary (PCB in the high-latitude ionosphere can be crucial for studies concerned with the dynamics of the polar cap, e.g. the measurement of reconnection rates. The Doppler spectral width characteristics of backscatter received by the SuperDARN HF radars have been previously used for locating and tracking the PCB in the cusp region. The boundary is generally observed in meridional beams of the SuperDARN radars and appears as a distinct change between low spectral width values observed equatorward of the cusp region, and high, but variable spectral width values observed within the cusp region. To identify the spectral width boundary (SWB between these two regions, a simple algorithm employing a spectral width threshold has often been applied to the data. However, there is not, as yet, a standard algorithm, or spectral width threshold, which is universally applied. Nor has there been any rigorous assessment of the accuracy of this method of boundary determination. This study applies a series of threshold algorithms to a simulated cusp-region spectral width data set, to assess the accuracy of different algorithms. This shows that simple threshold algorithms correctly identify the boundary location in, at the most, 50% of the cases and that the average boundary error is at least ~ 1–2 range gates (~ 1° latitude. It transpires that spatial and temporal smoothing of the spectral width data (e.g. by median filtering, before application of a threshold algorithm can increase the boundary determination accuracy to over 95% and the average boundary error to much less than a range gate. However, this is sometimes at the cost of temporal resolution in the motion of the boundary location. The algorithms are also applied to a year’s worth of spectral width data from the cusp ionosphere, measured by the Halley SuperDARN radar in Antarctica. This analysis highlights the increased accuracy of

  13. Accurately measuring sea level change from space: an ESA climate change initiative for MSL closure budget studies

    Science.gov (United States)

    Legeais, JeanFrancois; Benveniste, Jérôme

    2016-07-01

    Sea level is a very sensitive index of climate change and variability. Sea level integrates the ocean warming, mountain glaciers and ice sheet melting. Understanding the sea level variability and changes implies an accurate monitoring of the sea level variable at climate scales, in addition to understanding the ocean variability and the exchanges between ocean, land, cryosphere, and atmosphere. That is why Sea Level is one of the Essential Climate Variables (ECV) selected in the frame of the ESA Climate Change Initiative (CCI) program. It aims at providing long-term monitoring of the sea level ECV with regular updates, as required for climate studies. The program is now in its second phase of 3 year (following phase I during 2011-2013). The objectives are firstly to involve the climate research community, to refine their needs and collect their feedbacks on product quality. And secondly to develop, test and select the best algorithms and standards to generate an updated climate time series and to produce and validate the Sea Level ECV product. This will better answer the climate user needs by improving the quality of the Sea Level products and maintain a sustain service for an up-to-date production. This has led to the production of a first version of the Sea Level ECV which has benefited from yearly extensions and now covers the period 1993-2014. Within phase II, new altimeter standards have been developed and tested in order to reprocess the dataset with the best standards for climate studies. The reprocessed ECV will be released in summer 2016. We will present the main achievements of the ESA CCI Sea Level Project. On the one hand, the major steps required to produce the 22 years climate time series are briefly described: collect and refine the user requirements, development of adapted algorithms for climate applications and specification of the production system. On the other hand, the product characteristics are described as well as the results from product

  14. The Cobas AmpliPrep/Cobas TaqMan HCV Test, Version 2.0, Real-Time PCR Assay Accurately Quantifies Hepatitis C Virus Genotype 4 RNA

    OpenAIRE

    Chevaliez, Stéphane; Bouvier-Alias, Magali; Rodriguez, Christophe; Soulier, Alexandre; Poveda, Jean-Dominique; Pawlotsky, Jean-Michel

    2013-01-01

    Accurate hepatitis C virus (HCV) RNA quantification is mandatory for the management of chronic hepatitis C therapy. The first-generation Cobas AmpliPrep/Cobas TaqMan HCV test (CAP/CTM HCV) underestimated HCV RNA levels by >1-log10 international units/ml in a number of patients infected with HCV genotype 4 and occasionally failed to detect it. The aim of this study was to evaluate the ability of the Cobas AmpliPrep/Cobas TaqMan HCV test, version 2.0 (CAP/CTM HCV v2.0), to accurately quantify H...

  15. Correction of nutrition test errors for more accurate quantification of the link between dental health and malnutrition.

    Science.gov (United States)

    Dion, Nathalie; Cotart, Jean-Louis; Rabilloud, Muriel

    2007-04-01

    We quantified the link between tooth deterioration and malnutrition in institutionalized elderly subjects, taking into account the major risk factors for malnutrition and adjusting for the measurement error made in using the Mini Nutritional Assessment questionnaire. Data stem from a survey conducted in 2005 in 1094 subjects >or=60 y of age from a large sample of 100 institutions of the Rhône-Alpes region of France. A Bayesian approach was used to quantify the effect of tooth deterioration on malnutrition through a two-level logistic regression. This approach allowed taking into account the uncertainty on sensitivity and specificity of the Mini Nutritional Assessment questionnaire to adjust for the measurement error of that test. After adjustment for other risk factors, the risk of malnutrition increased significantly and continuously 1.15 times (odds ratio 1.15, 95% credibility interval 1.06-1.25) whenever the masticatory percentage decreased by 10 points, which is equivalent to the loss of two molars. The strongest factors that augmented the probability of malnutrition were deglutition disorders, depression, and verbal inconsistency. Dependency was also an important factor; the odds of malnutrition nearly doubled for each additional grade of dependency (graded 6 to 1). Diabetes, central neurodegenerative disease, and carcinoma tended to increase the probability of malnutrition but their effect was not statistically significant. Dental status should be considered a serious risk factor for malnutrition. Regular dental examination and care should preserve functional dental integrity to prevent malnutrition in institutionalized elderly people.

  16. Cumulative Measurement Errors for Dynamic Testing of Space Flight Hardware

    Science.gov (United States)

    Winnitoy, Susan

    2012-01-01

    Located at the NASA Johnson Space Center in Houston, TX, the Six-Degree-of-Freedom Dynamic Test System (SDTS) is a real-time, six degree-of-freedom, short range motion base simulator originally designed to simulate the relative dynamics of two bodies in space mating together (i.e., docking or berthing). The SDTS has the capability to test full scale docking and berthing systems utilizing a two body dynamic docking simulation for docking operations and a Space Station Remote Manipulator System (SSRMS) simulation for berthing operations. The SDTS can also be used for nonmating applications such as sensors and instruments evaluations requiring proximity or short range motion operations. The motion base is a hydraulic powered Stewart platform, capable of supporting a 3,500 lb payload with a positional accuracy of 0.03 inches. The SDTS is currently being used for the NASA Docking System testing and has been also used by other government agencies. The SDTS is also under consideration for use by commercial companies. Examples of tests include the verification of on-orbit robotic inspection systems, space vehicle assembly procedures and docking/berthing systems. The facility integrates a dynamic simulation of on-orbit spacecraft mating or de-mating using flight-like mechanical interface hardware. A force moment sensor is used for input during the contact phase, thus simulating the contact dynamics. While the verification of flight hardware presents unique challenges, one particular area of interest involves the use of external measurement systems to ensure accurate feedback of dynamic contact. The measurement systems for the test facility have two separate functions. The first is to take static measurements of facility and test hardware to determine both the static and moving frames used in the simulation and control system. The test hardware must be measured after each configuration change to determine both sets of reference frames. The second function is to take dynamic

  17. Thermal tests for laser Doppler perfusion measurements in Raynaud's syndrome

    Science.gov (United States)

    Kacprzak, Michal; Skora, A.; Obidzinska, J.; Zbiec, A.; Maniewski, Roman; Staszkiewicz, W.

    2004-07-01

    The laser Doppler method offers a non-invasive, real time technique for monitoring of blood perfusion in microcirculation. In practical measurements the perfusion index is given only in relative values. Thus, accurate and reproducible results can be only obtained when using a well controlled stimulation test. The aim of this study was evaluation of the thermal stimulation test, which is frequently used to investigate microcirculation in patients with Raynaud's syndrome. Three types of thermal tests, in which air or water with temperature in range 5°C - 40°C were used. Ten normal volunteers and fifteen patients with clinical symptoms of the primary Raynaud's syndrome were enrolled in this study. To estimate skin microcirculation changes during the thermal test, the multichannel laser Doppler system and laser Doppler scanner were used. The obtained results were analyzed from the point of view of the efficiency of these methods and the thermal provocative tests in differentiation of normal subjects and patient with Raynaud's syndrome.

  18. Method for more accurate transmittance measurements of low-angle scattering samples using an integrating sphere with an entry port beam diffuser

    International Nuclear Information System (INIS)

    Nilsson, Annica M.; Jonsson, Andreas; Jonsson, Jacob C.; Roos, Arne

    2011-01-01

    For most integrating sphere measurements, the difference in light distribution between a specular reference beam and a diffused sample beam can result in significant errors. The problem becomes especially pronounced in integrating spheres that include a port for reflectance or diffuse transmittance measurements. The port is included in many standard spectrophotometers to facilitate a multipurpose instrument, however, absorption around the port edge can result in a detected signal that is too low. The absorption effect is especially apparent for low-angle scattering samples, because a significant portion of the light is scattered directly onto that edge. In this paper, a method for more accurate transmittance measurements of low-angle light-scattering samples is presented. The method uses a standard integrating sphere spectrophotometer, and the problem with increased absorption around the port edge is addressed by introducing a diffuser between the sample and the integrating sphere during both reference and sample scan. This reduces the discrepancy between the two scans and spreads the scattered light over a greater portion of the sphere wall. The problem with multiple reflections between the sample and diffuser is successfully addressed using a correction factor. The method is tested for two patterned glass samples with low-angle scattering and in both cases the transmittance accuracy is significantly improved.

  19. An improved approach for accurate and efficient measurement of common carotid artery intima-media thickness in ultrasound images.

    Science.gov (United States)

    Li, Qiang; Zhang, Wei; Guan, Xin; Bai, Yu; Jia, Jing

    2014-01-01

    The intima-media thickness (IMT) of common carotid artery (CCA) can serve as an important indicator for the assessment of cardiovascular diseases (CVDs). In this paper an improved approach for automatic IMT measurement with low complexity and high accuracy is presented. 100 ultrasound images from 100 patients were tested with the proposed approach. The ground truth (GT) of the IMT was manually measured for six times and averaged, while the automatic segmented (AS) IMT was computed by the algorithm proposed in this paper. The mean difference±standard deviation between AS and GT IMT is 0.0231±0.0348 mm, and the correlation coefficient between them is 0.9629. The computational time is 0.3223 s per image with MATLAB under Windows XP on an Intel Core 2 Duo CPU E7500 @2.93 GHz. The proposed algorithm has the potential to achieve real-time measurement under Visual Studio.

  20. An Improved Approach for Accurate and Efficient Measurement of Common Carotid Artery Intima-Media Thickness in Ultrasound Images

    Directory of Open Access Journals (Sweden)

    Qiang Li

    2014-01-01

    Full Text Available The intima-media thickness (IMT of common carotid artery (CCA can serve as an important indicator for the assessment of cardiovascular diseases (CVDs. In this paper an improved approach for automatic IMT measurement with low complexity and high accuracy is presented. 100 ultrasound images from 100 patients were tested with the proposed approach. The ground truth (GT of the IMT was manually measured for six times and averaged, while the automatic segmented (AS IMT was computed by the algorithm proposed in this paper. The mean difference ± standard deviation between AS and GT IMT is 0.0231 ± 0.0348 mm, and the correlation coefficient between them is 0.9629. The computational time is 0.3223 s per image with MATLAB under Windows XP on an Intel Core 2 Duo CPU E7500 @2.93 GHz. The proposed algorithm has the potential to achieve real-time measurement under Visual Studio.

  1. S3 HMBC: Spin-State-Selective HMBC for accurate measurement of homonuclear coupling constants. Application to strychnine yielding thirteen hitherto unreported JHH

    DEFF Research Database (Denmark)

    Kjaerulff, Louise; Benie, Andrew J.; Hoeck, Casper

    2016-01-01

    A novel method, Spin-State-Selective (S3) HMBC, for accurate measurement of homonuclear coupling constants is introduced. As characteristic for S3 techniques, S3 HMBC yields independent subspectra corresponding to particular passive spin states and thus allows determination of coupling constants ...... are demonstrated by an application to strychnine where thirteen JHH coupling constants not previously reported could be measured....

  2. Testing the ability of children with attention deficit hyperactivity disorder to accurately report the effects of medication on their behavior.

    OpenAIRE

    Ardoin, S P; Martens, B K

    2000-01-01

    Children with attention deficit hyperactivity disorder (ADHD) are often treated with central nervous system stimulants, making the evaluation of medication effects an important topic for applied behavior analysts. Because assessment protocols emphasize informant reports and direct observations of child behavior, little is known about the extent to which children themselves can accurately report medication effects. Double-blind placebo-controlled procedures were used to examine whether 6 child...

  3. Measured and calculated isotopes for a gadolinia lead test assembly

    International Nuclear Information System (INIS)

    Hove, C.M.

    1990-01-01

    The US Department of Energy, Duke Power Company, and the B and W Fuel Company participated in an extended burnup project to develop, irradiate, and examine an advanced fuel assembly design for pressurized water reactors. The assembly uses a urania-gadolinia (UO 2 -Gd 2 O 3 ) burnable absorber fuel mixture along with other fuel performance and design features that enhance uranium utilization. Previous milestones in the gadolinia development of the extended burnup project include development and verification of a neutronics model, measurement of materials properties of gadolinia fuel, and a successful gadolinia lead test assembly (LTA) program. One LTA was discharged as planned after one cycle, four LTAs continued for two more cycles, and one LTA of these four underwent a fourth cycle and reached 58,310 MWd/ton U assembly-average burnup, a world record at the time. Hot-cell destructive examination of gadolinia and non-gadolinia fuel rods from the single-cycle LTA (406.2 effective full-power days irradiation) has been completed. The comparison of measured and calculated isotopics for this LTA is the subject of this paper. A comparison of measured and calculated power distributions is also given, because accurate prediction of core performance during power production is ultimately the most important test of a calculational model

  4. Acoustic emission measurement during instrumented impact tests

    International Nuclear Information System (INIS)

    Crostack, H.A.; Engelhardt, A.H.

    1983-01-01

    Results of instrumented impact tests are discussed. On the one hand the development of the loading process at the hammer tup was recorded by means of a piezoelectric transducer. This instrumentation supplied a better representation of the load versus time than the conventional strain gauges. On the other hand the different types of acoustic emission occurring during a test could be separated. The acoustic emission released at the impact of the hammer onto the specimen is of lower frequency and its spectrum is strongly decreasing with increasing frequency. Plastic deformation also emits signals of lower frequency that are of quasi-continuous character. Both signal types can be discriminated by filtering. As a consequence typical burst signal were received afterwards that can be correlated with crack propagation. Their spectra exhibit considerable portions up to about 1.9 MHz. The development in time of the burst signals points to the kind of crack propagation resp. its sequence of appearance. However, definitive comparison between load and acoustic emission should become possible, only when the disadvantages of the common load measurement can be reduced, e.g. by determining the load directly at the specimen instead of the hammer tup

  5. Tumor volume in subcutaneous mouse xenografts measured by microCT is more accurate and reproducible than determined by 18F-FDG-microPET or external caliper

    OpenAIRE

    Jensen, Mette Munk; Jørgensen, Jesper Tranekjær; Binderup, Tina; Kjær, Andreas

    2008-01-01

    Abstract Background In animal studies tumor size is used to assess responses to anticancer therapy. Current standard for volumetric measurement of xenografted tumors is by external caliper, a method often affected by error. The aim of the present study was to evaluate if microCT gives more accurate and reproducible measures of tumor size in mice compared with caliper measurements. Furthermore, we evaluated the accuracy of tumor volume determined from 18F-fluorodeoxyglucose (18F-FDG) PET. Meth...

  6. Measuring What Matters: Robert Sternberg's Enlightened Approach to Admissions Testing

    Science.gov (United States)

    Grace, Catherine O'Neill

    2011-01-01

    Psychologist Robert J. Sternberg's conviction that American standardized testing does not accurately reflect a child's intelligence or potential is far from theoretical. As an elementary school student in the 1950s, he scored poorly on the ubiquitous IQ test of the time, freezing up when the school psychologist entered the room. Thankfully for…

  7. Reliability of skin testing as a measure of nutritional state

    International Nuclear Information System (INIS)

    Forse, R.A.; Christou, N.; Meakins, J.L.; MacLean, L.D.; Shizgal, H.M.

    1981-01-01

    The reliability of skin testing to assess the nutritional state was evaluated in 257 patients who received total parenteral nutrition (TPN). The nutritional state was assessed by determining body composition, by multiple-isotope dilution. Immunocompetence was simultaneously evaluated by skin testing with five recall antigens. These measurements were carried out before and at two-week intervals during TPN. A statistically significant relationship existed between the response to skin testing and the nutritional state. A body composition consistent with malnutrition was present in the anergic patients, while body composition was normal in the patients who reacted normally to skin testing. However, a considerable overlap existed as 43% of the reactive patients were malnourished, and 21% of the anergic patients were normally nourished. Thirty-seven (43%) of the 86 anergic patients converted and became reactive during TPN, and their body composition improved significantly. The remaining 49 anergic patients (57%) did not convert, and their body composition did not change despite similar nutritional support. The principal difference between the two groups of anergic patients was the nature of the therapy administered. In the anergic patients who converted, therapy was aggressive and appropriate, and clinical improvement occurred in 23 (62.2%) of the patients, with a mortality of 5.4%. In the 49 patients who remained anergic, therapy was often inappropriate or unsuccessful, with clinical improvement in only three (6.1%) of the patients and a mortality of 42.8%. The data demonstrated a significant relationship between the response to skin testing and the nutritional state. However, because of the wide overlap, skin testing does not accurately assess a person's nutritional state. The persistence of the anergic state is indicative of a lack of response to therapy

  8. Direct susceptibility testing by disk diffusion on clinical samples : a rapid and accurate tool for antibiotic stewardship

    NARCIS (Netherlands)

    Coorevits, L.; Boelens, J.; Claeys, G.

    We compared the accuracy of direct susceptibility testing (DST) with conventional antimicrobial susceptibility testing (AST), both using disk diffusion, on clinical samples. A total of 123 clinical samples (respiratory tract samples, urine, vaginal and abdominal abscess discharges, bile fluid and a

  9. Dredging Research, Volume 3, No. 3. DNA Technology to Impact Dredged Material Projects through Faster, More Accurate Testing Methods

    National Research Council Canada - National Science Library

    McDonald, Allison

    2000-01-01

    .... Most people associate DNA with criminal cases and paternity testing, but thanks to research projects such as the Human Genome Project, which has isolated and identified thousands of genes, many...

  10. Measuring Test Case Similarity to Support Test Suite Understanding

    NARCIS (Netherlands)

    Greiler, M.S.; Van Deursen, A.; Zaidman, A.E.

    2012-01-01

    Preprint of paper published in: TOOLS 2012 - Proceedings of the 50th International Conference, Prague, Czech Republic, May 29-31, 2012; doi:10.1007/978-3-642-30561-0_8 In order to support test suite understanding, we investigate whether we can automatically derive relations between test cases. In

  11. Testing the hierarchical assembly of massive galaxies using accurate merger rates out to z ˜ 1.5

    Science.gov (United States)

    Rodrigues, Myriam; Puech, M.; Flores, H.; Hammer, F.; Pirzkal, N.

    2018-04-01

    We established an accurate comparison between observationally and theoretically estimated major merger rates over a large range of mass (log Mbar/M⊙ =9.9-11.4) and redshift (z = 0.7-1.6). For this, we combined a new estimate of the merger rate from an exhaustive count of pairs within the virial radius of massive galaxies at z ˜ 1.265 and cross-validated with their morphology, with estimates from the morpho-kinematic analysis of two other samples. Theoretical predictions were estimated using semi-empirical models with inputs matching the properties of the observed samples, while specific visibility time-scales scaled to the observed samples were used. Both theory and observations are found to agree within 30 per cent of the observed value, which provides strong support to the hierarchical assembly of galaxies over the probed ranges of mass and redshift. Here, we find that ˜60 per cent of population of local massive (Mstellar =1010.3-11.6 M⊙) galaxies would have undergone a wet major merger since z = 1.5, consistently with previous studies. Such recent mergers are expected to result in the (re-)formation of a significant fraction of local disc galaxies.

  12. VALORATE: fast and accurate log-rank test in balanced and unbalanced comparisons of survival curves and cancer genomics.

    Science.gov (United States)

    Treviño, Victor; Tamez-Pena, Jose

    2017-06-15

    The association of genomic alterations to outcomes in cancer is affected by a problem of unbalanced groups generated by the low frequency of alterations. For this, an R package (VALORATE) that estimates the null distribution and the P -value of the log-rank based on a recent reformulation is presented. For a given number of alterations that define the size of survival groups, the log-rank density is estimated by a weighted sum of conditional distributions depending on a co-occurrence term of mutations and events. The estimations are accurately accelerated by sampling across co-occurrences allowing the analysis of large genomic datasets in few minutes. In conclusion, the proposed VALORATE R package is a valuable tool for survival analysis. The R package is available in CRAN at https://cran.r-project.org and in http://bioinformatica.mty.itesm.mx/valorateR . vtrevino@itesm.mx. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

  13. Accounting for Interference, Scattering, and Electrode Absorption to Make Accurate Internal Quantum Efficiency Measurements in Organic and Other Thin Solar Cells

    KAUST Repository

    Burkhard, George F.

    2010-05-31

    Accurately measuring internal quantum efficiency requires knowledge of absorption in the active layer of a solar cell. The experimentally accessible total absorption includes significant contributions from the electrodes and other nonactive layers. We suggest a straightforward method for calculating the active layer contribution that minimizes error by subtracting optically-modeled electrode absorption from experimentally measured total absorption. (Figure Presented) © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. A new soil test for quantitative measurement of available and adsorbed boron

    Science.gov (United States)

    Boron soil tests currently in use, do not extract all plant available B but are used by relating the extractable amount of B to plant B content. There is a need to accurately measure all plant available or adsorbed B because B can be toxic to plants at elevated concentrations and can cause marked y...

  15. Accurately measuring sea level change from space: an ESA Climate Change Initiative for MSL closure budget studies

    DEFF Research Database (Denmark)

    Legeais, Jean-Francois; Cazenave, Anny; Larnicol, Gille

    to understanding the ocean variability and the exchanges between ocean, land, cryosphere, and atmosphere. That is why Sea Level is one of the Essential Climate Variables (ECV) selected in the frame of the ESA Climate Change Initiative (CCI) program. It aims at providing long-term monitoring of the sea level ECV......Sea level is a very sensitive index of climate change and variability. Sea level integrates the ocean warming, mountain glaciers and ice sheet melting. Understanding the sea level variability and changes implies an accurate monitoring of the sea level variable at climate scales, in addition...... with regular updates, as required for climate studies. After a first phase (2011-2013), the program has started in 2014 a second phase of 3 years. The objectives of this second phase are to involve the climate research community, to refine their needs and collect their feedbacks on product quality, to develop...

  16. Noninvasive Tests Do Not Accurately Differentiate Nonalcoholic Steatohepatitis From Simple Steatosis: A Systematic Review and Meta-analysis.

    Science.gov (United States)

    Verhaegh, Pauline; Bavalia, Roisin; Winkens, Bjorn; Masclee, Ad; Jonkers, Daisy; Koek, Ger

    2017-08-22

    Non-alcoholic fatty liver disease is a rapidly increasing health problem. Liver biopsy analysis is the most sensitive test to differentiate between non-alcoholic steatohepatitis (NASH) and simple steatosis (SS), but non-invasive methods are needed. We performed a systematic review and meta-analysis of non-invasive tests for differentiating NASH from SS, focusing on blood markers. We performed a systematic search of the PubMed, Medline and Embase (1990-2016) databases using defined keywords, limited to full-text papers in English and human adults, and identified 2608 articles. Two independent reviewers screened the articles and identified 122 eligible articles that used liver biopsy as reference standard. If at least 2 studies were available, pooled sensitivity (sens p ) and specificity (spec p ) values were determined using the Meta-Analysis Package for R (metafor). In the 122 studies analyzed, 219 different blood markers (107 single markers and 112 scoring systems) were identified to differentiate NASH from simple steatosis, and 22 other diagnostic tests were studied. Markers identified related to several pathophysiological mechanisms. The markers analyzed in the largest proportions of studies were alanine aminotransferase (sens p , 63.5% and spec p , 74.4%) within routine biochemical tests, adiponectin (sensp, 72.0% and spec p , 75.7%) within inflammatory markers, CK18-M30 (sens p , 68.4% and spec p , 74.2%) within markers of cell death or proliferation and homeostatic model assessment of insulin resistance (sens p , 69.0% and spec p , 72.7%) within the metabolic markers. Two scoring systems could also be pooled: the NASH test (differentiated NASH from borderline NASH plus simple steatosis with 22.9% sens p and 95.3% spec p ) and the GlycoNASH test (67.1% sens p and 63.8% spec p ). In the meta-analysis, we found no test to differentiate NASH from SS with a high level of pooled sensitivity and specificity (≥80%). However, some blood markers, when included in

  17. Measuring test coverage of SoA services

    NARCIS (Netherlands)

    Sneed, Harry M.; Verhoef, Chris

    2015-01-01

    One of the challenges of testing in a SoA environment is that testers do not have access to the source code of the services they are testing. Therefore they are not able to measure test coverage at the code level, as is done in conventional white-box testing. They are compelled to measure test

  18. Fast recovery strain measurements in a nuclear test environment

    International Nuclear Information System (INIS)

    Kitchen, W.R.; Nauman, W.J.; Vollmer, D.W.

    1979-01-01

    The recovery of early-time (50 μs or less) strain gage data on structural response experiments in underground nuclear tests has been a continuing problem for experimenters at the Nevada Test Site. Strain measurement is one of the primary techniques used to obtain experimental data for model verification and correlation with predicted effects. Peak strains generally occur within 50 to 100 μs of the radiation exposure. Associated with the exposure is an intense electromagnetic impulse that produces potentials of kilovolts and currents of kiloamperes on the experimental structures. For successful operation, the transducer and associated recording system must recover from the initial noise overload and accurately track the strain response within about 50 μs of the nuclear detonation. A gaging and fielding technique and a recording system design that together accomplish these objectives are described. Areas discussed include: (1) noise source model; (2) experimental cassette design, gage application, grounding, and shielding; (3) cable design and shielding between gage and recorder; (4) recorder design including signal conditioner/amplifier, digital encoder, buffer memory, and uphole data transmission; and (5) samples of experimental data

  19. What do educational test scores really measure?

    DEFF Research Database (Denmark)

    McIntosh, James; D. Munk, Martin

    Latent class Poisson count models are used to analyze a sample of Danish test score results from a cohort of individuals born in 1954-55 and tested in 1968. The procedure takes account of unobservable effects as well as excessive zeros in the data. The bulk of unobservable effects are uncorrelate...

  20. Measurement and analysis to DIW of chassis dynamometers for automobile emissions testing

    Science.gov (United States)

    Zhu, Weimin; Wang, Dayong; Qi, Fang; Yang, Dengcai

    2010-12-01

    DIW (Dynamometer Inertia Weight) of 'chassis dynamometers for automobile emissions testing' is a total inertia weight of all rotating components in the chassis dynamometer. Total Inertia weight is a inertia device simulates translational and rotational kinetic energy of a traveling vehicle which is equivalent to the mass of the car. DIW is an important technical indicator, whether it is accurate or not will affect the calibration of all technical characteristics of 'chassis dynamometers for automobile emissions testing'. In this paper,first of all, we introduce a new method to measure the Dynamometer Inertia Weight, that is, coast-down testing with twice constant-force loading method, and we derivate a formula to calculate the Dynamometer Inertia Weight from kinetic energy conservation law. Secondly, we have done a lot of coast-down testings with twice constant-force load method. After analyzing the data, we found out the factors that affect the testing processes and the accuracy of testing results. Finally, after comparing twice constant-force loading method with the take-down flywheel method and twice constant-power loading method, we know that this coast-down testing with twice constant-force loading method is better than other methods in stability and repeatability and testing data will be more accurate. It's a accurate and convenient way to measure the DIW of 'chassis dynamometers for automobile emissions testing'.

  1. Accurate clinical genetic testing for autoinflammatory diseases using the next-generation sequencing platform MiSeq

    Directory of Open Access Journals (Sweden)

    Manabu Nakayama

    2017-03-01

    Full Text Available Autoinflammatory diseases occupy one of a group of primary immunodeficiency diseases that are generally thought to be caused by mutation of genes responsible for innate immunity, rather than by acquired immunity. Mutations related to autoinflammatory diseases occur in 12 genes. For example, low-level somatic mosaic NLRP3 mutations underlie chronic infantile neurologic, cutaneous, articular syndrome (CINCA, also known as neonatal-onset multisystem inflammatory disease (NOMID. In current clinical practice, clinical genetic testing plays an important role in providing patients with quick, definite diagnoses. To increase the availability of such testing, low-cost high-throughput gene-analysis systems are required, ones that not only have the sensitivity to detect even low-level somatic mosaic mutations, but also can operate simply in a clinical setting. To this end, we developed a simple method that employs two-step tailed PCR and an NGS system, MiSeq platform, to detect mutations in all coding exons of the 12 genes responsible for autoinflammatory diseases. Using this amplicon sequencing system, we amplified a total of 234 amplicons derived from the 12 genes with multiplex PCR. This was done simultaneously and in one test tube. Each sample was distinguished by an index sequence of second PCR primers following PCR amplification. With our procedure and tips for reducing PCR amplification bias, we were able to analyze 12 genes from 25 clinical samples in one MiSeq run. Moreover, with the certified primers designed by our short program—which detects and avoids common SNPs in gene-specific PCR primers—we used this system for routine genetic testing. Our optimized procedure uses a simple protocol, which can easily be followed by virtually any office medical staff. Because of the small PCR amplification bias, we can analyze simultaneously several clinical DNA samples with low cost and can obtain sufficient read numbers to detect a low level of

  2. Multidetector-Row Computed Tomography Allows Accurate Measurement of Mechanical Prosthetic Heart Valve Leaflet Closing Angles Compared With Fluoroscopy

    NARCIS (Netherlands)

    Suchá, Dominika; Symersky, Petr; Vonken, Evert-Jan P. A.; Provoost, Esther; Chamuleau, Steven A. J.; Budde, Ricardo P. J.

    2014-01-01

    Purpose: The purpose of this study was to compare multidetector-row computed tomography (MDCT) leaflet restriction measurements with fluoroscopy measurements in commonly used mechanical prosthetic heart valves (PHVs). Methods: Four mechanical PHVs (ON-X, Carbomedics, St. Jude, and Medtronic Hall)

  3. Fast and accurate measurement of on-axis gain and on-axis polarization at a finite distance

    DEFF Research Database (Denmark)

    Pivnenko, S.; Breinbjerg, O.

    2013-01-01

    to reduce the amount of measurement data and thus measurement time, the phase centre location is found on a sparse frequency grid and the values in the intermediate points are found by interpolation. The antenna polarization is determined from the amplitude/phase frequency sweeps with two orthogonal AUT...

  4. The detection of the methylated Wif-1 gene is more accurate than a fecal occult blood test for colorectal cancer screening

    KAUST Repository

    Amiot, Aurelien

    2014-07-15

    Background: The clinical benefit of guaiac fecal occult blood tests (FOBT) is now well established for colorectal cancer screening. Growing evidence has demonstrated that epigenetic modifications and fecal microbiota changes, also known as dysbiosis, are associated with CRC pathogenesis and might be used as surrogate markers of CRC. Patients and Methods: We performed a cross-sectional study that included all consecutive subjects that were referred (from 2003 to 2007) for screening colonoscopies. Prior to colonoscopy, effluents (fresh stools, sera-S and urine-U) were harvested and FOBTs performed. Methylation levels were measured in stools, S and U for 3 genes (Wif1, ALX-4, and Vimentin) selected from a panel of 63 genes; Kras mutations and seven dominant and subdominant bacterial populations in stools were quantified. Calibration was assessed with the Hosmer-Lemeshow chi-square, and discrimination was determined by calculating the C-statistic (Area Under Curve) and Net Reclassification Improvement index. Results: There were 247 individuals (mean age 60.8±12.4 years, 52% of males) in the study group, and 90 (36%) of these individuals were patients with advanced polyps or invasive adenocarcinomas. A multivariate model adjusted for age and FOBT led to a C-statistic of 0.83 [0.77-0.88]. After supplementary sequential (one-by-one) adjustment, Wif-1 methylation (S or U) and fecal microbiota dysbiosis led to increases of the C-statistic to 0.90 [0.84-0.94] (p = 0.02) and 0.81 [0.74-0.86] (p = 0.49), respectively. When adjusted jointly for FOBT and Wif-1 methylation or fecal microbiota dysbiosis, the increase of the C-statistic was even more significant (0.91 and 0.85, p<0.001 and p = 0.10, respectively). Conclusion: The detection of methylated Wif-1 in either S or U has a higher performance accuracy compared to guaiac FOBT for advanced colorectal neoplasia screening. Conversely, fecal microbiota dysbiosis detection was not more accurate. Blood and urine testing could be

  5. Accurate single nucleotide variant detection in viral populations by combining probabilistic clustering with a statistical test of strand bias

    Science.gov (United States)

    2013-01-01

    Background Deep sequencing is a powerful tool for assessing viral genetic diversity. Such experiments harness the high coverage afforded by next generation sequencing protocols by treating sequencing reads as a population sample. Distinguishing true single nucleotide variants (SNVs) from sequencing errors remains challenging, however. Current protocols are characterised by high false positive rates, with results requiring time consuming manual checking. Results By statistical modelling, we show that if multiple variant sites are considered at once, SNVs can be called reliably from high coverage viral deep sequencing data at frequencies lower than the error rate of the sequencing technology, and that SNV calling accuracy increases as true sequence diversity within a read length increases. We demonstrate these findings on two control data sets, showing that SNV detection is more reliable on a high diversity human immunodeficiency virus sample as compared to a moderate diversity sample of hepatitis C virus. Finally, we show that in situations where probabilistic clustering retains false positive SNVs (for instance due to insufficient sample diversity or systematic errors), applying a strand bias test based on a beta-binomial model of forward read distribution can improve precision, with negligible cost to true positive recall. Conclusions By combining probabilistic clustering (implemented in the program ShoRAH) with a statistical test of strand bias, SNVs may be called from deeply sequenced viral populations with high accuracy. PMID:23879730

  6. Finite Element Modelling of a Field-Sensed Magnetic Suspended System for Accurate Proximity Measurement Based on a Sensor Fusion Algorithm with Unscented Kalman Filter.

    Science.gov (United States)

    Chowdhury, Amor; Sarjaš, Andrej

    2016-09-15

    The presented paper describes accurate distance measurement for a field-sensed magnetic suspension system. The proximity measurement is based on a Hall effect sensor. The proximity sensor is installed directly on the lower surface of the electro-magnet, which means that it is very sensitive to external magnetic influences and disturbances. External disturbances interfere with the information signal and reduce the usability and reliability of the proximity measurements and, consequently, the whole application operation. A sensor fusion algorithm is deployed for the aforementioned reasons. The sensor fusion algorithm is based on the Unscented Kalman Filter, where a nonlinear dynamic model was derived with the Finite Element Modelling approach. The advantage of such modelling is a more accurate dynamic model parameter estimation, especially in the case when the real structure, materials and dimensions of the real-time application are known. The novelty of the paper is the design of a compact electro-magnetic actuator with a built-in low cost proximity sensor for accurate proximity measurement of the magnetic object. The paper successively presents a modelling procedure with the finite element method, design and parameter settings of a sensor fusion algorithm with Unscented Kalman Filter and, finally, the implementation procedure and results of real-time operation.

  7. S3 HMBC hetero: Spin-State-Selective HMBC for accurate measurement of long-range heteronuclear coupling constants

    DEFF Research Database (Denmark)

    Hoeck, Casper; Gotfredsen, Charlotte Held; Sørensen, Ole W.

    2017-01-01

    A novel method, Spin-State-Selective (S3) HMBC hetero, for accurate measurement of heteronuclear coupling constants is introduced. The method extends the S3 HMBC technique for measurement of homonuclear coupling constants by appending a pulse sequence element that interchanges the polarization in...... of techniques, the accuracy of coupling constant measurement is independent of the size of the coupling constant of interest. The merits of the new method are demonstrated by application to vinyl acetate, the alkaloid strychnine, and the carbohydrate methyl β-maltoside....

  8. Testing the Feasibility of a Low-Cost Network Performance Measurement Infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Chevalier, Scott [Indiana Univ., Bloomington, IN (United States). International Networks; Schopf, Jennifer M. [Indiana Univ., Bloomington, IN (United States). International Networks; Miller, Kenneth [Pennsylvania State Univ., University Park, PA (United States). Telecommunications and Networking Services; Zurawski, Jason [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Sciences Network

    2016-07-01

    Todays science collaborations depend on reliable, high performance networks, but monitoring the end-to-end performance of a network can be costly and difficult. The most accurate approaches involve using measurement equipment in many locations, which can be both expensive and difficult to manage due to immobile or complicated assets. The perfSONAR framework facilitates network measurement making management of the tests more reasonable. Traditional deployments have used over-provisioned servers, which can be expensive to deploy and maintain. As scientific network uses proliferate, there is a desire to instrument more facets of a network to better understand trends. This work explores low cost alternatives to assist with network measurement. Benefits include the ability to deploy more resources quickly, and reduced capital and operating expenditures. Finally, we present candidate platforms and a testing scenario that evaluated the relative merits of four types of small form factor equipment to deliver accurate performance measurements.

  9. Accurate Masses, Radii, and Temperatures for the Eclipsing Binary V2154 Cyg, and Tests of Stellar Evolution Models

    Science.gov (United States)

    Bright, Jane; Torres, Guillermo

    2018-01-01

    We report new spectroscopic observations of the F-type triple system V2154 Cyg, in which two of the stars form an eclipsing binary with a period of 2.6306303 ± 0.0000038 days. We combine the results from our spectroscopic analysis with published light curves in the uvby Strömgren passbands to derive the first reported absolute dimensions of the stars in the eclipsing binary. The masses and radii are measured with high accuracy to better than 1.5% precision. For the primary and secondary respectively, we find that the masses are 1.269 ± 0.017 M⊙ and 0.7542 ± 0.0059 M⊙, the radii are 1.477 ± 0.012 R⊙ and 0.7232 ± 0.0091R⊙, and the temperatures are 6770 ± 150 K and 5020 ± 150 K. Current models of stellar evolution agree with the measured properties of the primary, but the secondary is larger than predicted. This may be due to activity in the secondary, as has been shown for other systems with a star of similar mass with this same discrepancy.The SAO REU program is funded by the National Science Foundation REU and Department of Defense ASSURE programs under NSF Grant AST-1659473, and by the Smithsonian Institution. GT acknowledges partial support for this work from NSF grant AST-1509375.

  10. Polydimethylsiloxane-air partition ratios for semi-volatile organic compounds by GC-based measurement and COSMO-RS estimation: Rapid measurements and accurate modelling.

    Science.gov (United States)

    Okeme, Joseph O; Parnis, J Mark; Poole, Justen; Diamond, Miriam L; Jantunen, Liisa M

    2016-08-01

    Polydimethylsiloxane (PDMS) shows promise for use as a passive air sampler (PAS) for semi-volatile organic compounds (SVOCs). To use PDMS as a PAS, knowledge of its chemical-specific partitioning behaviour and time to equilibrium is needed. Here we report on the effectiveness of two approaches for estimating the partitioning properties of polydimethylsiloxane (PDMS), values of PDMS-to-air partition ratios or coefficients (KPDMS-Air), and time to equilibrium of a range of SVOCs. Measured values of KPDMS-Air, Exp' at 25 °C obtained using the gas chromatography retention method (GC-RT) were compared with estimates from a poly-parameter free energy relationship (pp-FLER) and a COSMO-RS oligomer-based model. Target SVOCs included novel flame retardants (NFRs), polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), organophosphate flame retardants (OPFRs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). Significant positive relationships were found between log KPDMS-Air, Exp' and estimates made using the pp-FLER model (log KPDMS-Air, pp-LFER) and the COSMOtherm program (log KPDMS-Air, COSMOtherm). The discrepancy and bias between measured and predicted values were much higher for COSMO-RS than the pp-LFER model, indicating the anticipated better performance of the pp-LFER model than COSMO-RS. Calculations made using measured KPDMS-Air, Exp' values show that a PDMS PAS of 0.1 cm thickness will reach 25% of its equilibrium capacity in ∼1 day for alpha-hexachlorocyclohexane (α-HCH) to ∼ 500 years for tris (4-tert-butylphenyl) phosphate (TTBPP), which brackets the volatility range of all compounds tested. The results presented show the utility of GC-RT method for rapid and precise measurements of KPDMS-Air. Copyright © 2016. Published by Elsevier Ltd.

  11. Can the SENSIMED Triggerfish®lens data be used as an accurate measure of intraocular pressure?

    Science.gov (United States)

    Vitish-Sharma, Parveen; Acheson, Austin G; Stead, Richard; Sharp, John; Abbas, Ali; Hovan, Marta; Maxwell-Armstrong, Charles; Guo, Boliang; King, Anthony J

    2018-03-01

    The SENSIMED Triggerfish ® contact lens sensor (CLS) has an embedded micro-sensor that captures spontaneous circumferential changes at the corneoscleral junction and transmits them via an antenna to a device where these measurements are stored. During laparoscopic colorectal surgery, patients are placed in Trendelenburg position which has been shown to increase intraocular pressure (IOP). Laparoscopic colorectal surgery requires both pneumoperitoneum and Trendelenburg positioning; therefore, IOP can vary significantly. We aimed to assess whether circumferential changes in the corneoscleral area can be correlated to IOP changes measured using Tono-pen ® XL applanation tonometer during laparoscopic colorectal surgery. Patients undergoing laparoscopic colorectal resections were included. On the day of surgery, baseline IOP was taken and the SENSIMED Triggerfish ® CLS was then set up in one eye of the patient. During surgery (whilst under general anaesthetic), IOP measurements were taken in the contralateral eye using a Tono-pen ® XL applanation tonometer every hour and any time the table was moved to record the fluctuations of IOP during surgery and any association with position change. The timings of these readings were documented. Twenty patients were included in this study (six males, 14 females). Average age was 64.6 years (SD = 16.3). The fluctuation in IOP measured in the reference eye ranged between 6.3 and 46.7 mmHg. The mean correlation coefficient between CLS output measurements and these IOP measurements was r = 0.291 (95% CI). Our results showed a weak correlation between the SENSIMED Triggerfish ® CLS data output and IOP measurements taken using the Tono-pen ® XL applanation tonometer. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  12. Advancing Solar Irradiance Measurement for Climate-Related Studies: Accurate Constraint on Direct Aerosol Radiative Effect (DARE)

    Science.gov (United States)

    Tsay, Si-Chee; Ji, Q. Jack

    2011-01-01

    Earth's climate is driven primarily by solar radiation. As summarized in various IPCC reports, the global average of radiative forcing for different agents and mechanisms, such as aerosols or CO2 doubling, is in the range of a few W/sq m. However, when solar irradiance is measured by broadband radiometers, such as the fleet of Eppley Precision Solar Pyranometers (PSP) and equivalent instrumentation employed worldwide, the measurement uncertainty is larger than 2% (e.g., WMO specification of pyranometer, 2008). Thus, out of the approx. 184 W/sq m (approx.263 W/sq m if cloud-free) surface solar insolation (Trenberth et al. 2009), the measurement uncertainty is greater than +/-3.6 W/sq m, overwhelming the climate change signals. To discern these signals, less than a 1 % measurement uncertainty is required and is currently achievable only by means of a newly developed methodology employing a modified PSP-like pyranometer and an updated calibration equation to account for its thermal effects (li and Tsay, 2010). In this talk, we will show that some auxiliary measurements, such as those from a collocated pyrgeometer or air temperature sensors, can help correct historical datasets. Additionally, we will also demonstrate that a pyrheliometer is not free of the thermal effect; therefore, comparing to a high cost yet still not thermal-effect-free "direct + diffuse" approach in measuring surface solar irradiance, our new method is more economical, and more likely to be suitable for correcting a wide variety of historical datasets. Modeling simulations will be presented that a corrected solar irradiance measurement has a significant impact on aerosol forcing, and thus plays an important role in climate studies.

  13. Characterization of condenser microphones under different environmental conditions for accurate speed of sound measurements with acoustic resonators

    Energy Technology Data Exchange (ETDEWEB)

    Guianvarc' h, Cecile; Pitre, Laurent [Laboratoire Commun de Metrologie LNE/Cnam, 61 rue du Landy, 93210 La Plaine Saint Denis (France); Gavioso, Roberto M.; Benedetto, Giuliana [Istituto Nazionale di Ricerca Metrologica, Strada delle Cacce 91, 10135 Turin (Italy); Bruneau, Michel [Laboratoire d' Acoustique de l' Universite du Maine UMR CNRS 6613, av. Olivier Messiaen, 72085 Le Mans Cedex 9 (France)

    2009-07-15

    Condenser microphones are more commonly used and have been extensively modeled and characterized in air at ambient temperature and static pressure. However, several applications of interest for metrology and physical acoustics require to use these transducers in significantly different environmental conditions. Particularly, the extremely accurate determination of the speed of sound in monoatomic gases, which is pursued for a determination of the Boltzmann constant k by an acoustic method, entails the use of condenser microphones mounted within a spherical cavity, over a wide range of static pressures, at the temperature of the triple point of water (273.16 K). To further increase the accuracy achievable in this application, the microphone frequency response and its acoustic input impedance need to be precisely determined over the same static pressure and temperature range. Few previous works examined the influence of static pressure, temperature, and gas composition on the microphone's sensitivity. In this work, the results of relative calibrations of 1/4 in. condenser microphones obtained using an electrostatic actuator technique are presented. The calibrations are performed in pure helium and argon gas at temperatures near 273 K and in the pressure range between 10 and 600 kPa. These experimental results are compared with the predictions of a realistic model available in the literature, finding a remarkable good agreement. The model provides an estimate of the acoustic impedance of 1/4 in. condenser microphones as a function of frequency and static pressure and is used to calculate the corresponding frequency perturbations induced on the normal modes of a spherical cavity when this is filled with helium or argon gas.

  14. Multidetector-row computed tomography allows accurate measurement of mechanical prosthetic heart valve leaflet closing angles compared with fluoroscopy.

    Science.gov (United States)

    Suchá, Dominika; Symersky, Petr; Vonken, Evert-Jan P A; Provoost, Esther; Chamuleau, Steven A J; Budde, Ricardo P J

    2014-01-01

    The purpose of this study was to compare multidetector-row computed tomography (MDCT) leaflet restriction measurements with fluoroscopy measurements in commonly used mechanical prosthetic heart valves (PHVs). Four mechanical PHVs (ON-X, Carbomedics, St. Jude, and Medtronic Hall) were imaged in a pulsatile model using fluoroscopy and 64-detector-row computed tomography. Five image acquisitions of each PHV without (1) and with (4) restricted leaflet closure were made. Three observers measured closure angles on fluoroscopy and MDCT. Data were analyzed using intraclass correlation coefficient (ICC) and Bland-Altman plots. Interobserver agreement was high in restricted and non-restricted leaflets on both modalities (ICCs >0.995). MDCT and fluoroscopy showed high agreements (ICCs >0.989). Median MDCT closure angle measurements differed at most -2 to +2 degrees from fluoroscopy in the restricted and -1 to +2 degrees in the non-restricted leaflets. MDCT allows measurement of leaflet motion with a maximal median discrepancy of 2 degrees. Both MDCT and fluoroscopy detect restricted leaflet closure with great accuracy.

  15. Accurate tissue area measurements with considerably reduced radiation dose achieved by patient-specific CT scan parameters

    DEFF Research Database (Denmark)

    Brandberg, J.; Bergelin, E.; Sjostrom, L.

    2008-01-01

    A low-dose technique was compared with a standard diagnostic technique for measuring areas of adipose and muscle tissue and CT numbers for muscles in a body composition application. The low-dose technique was intended to keep the expected deviation in the measured area of adipose and muscle tissue...... for muscle tissue. Image noise was quantified by standard deviation measurements. The area deviation was radiation dose of the low-dose technique was reduced to 2-3% for diameters of 31-35 cm and to 7.5-50% for diameters of 36-47 cm...... as compared with the integral dose by the standard diagnostic technique. The CT numbers of muscle tissue remained unchanged with reduced radiation dose. Image noise was on average 20.9 HU (Hounsfield units) for subjects with diameters of 31-35 cm and 11.2 HU for subjects with diameters in the range of 36...

  16. Is a standalone inertial measurement unit accurate and precise enough for quantification of movement symmetry in the horse?

    DEFF Research Database (Denmark)

    Brighton, Charlotte; Olsen, Emil; Pfau, Thilo

    2015-01-01

    Standalone ‘low-cost’ inertial measurement units (IMUs) could facilitate large-scale studies into establishing minimal important differences (MID) for orthopaedic deficits (lameness) in horses. We investigated accuracy and limits of agreement (LoA) after correction of magnitude-dependent differen......Standalone ‘low-cost’ inertial measurement units (IMUs) could facilitate large-scale studies into establishing minimal important differences (MID) for orthopaedic deficits (lameness) in horses. We investigated accuracy and limits of agreement (LoA) after correction of magnitude......-dependent differences of a standalone 6 degree-of-freedom IMU compared with an established IMU-based gait analysis system (MTx) in six horses for two anatomical landmarks (sacrum and sternum). Established symmetry measures were calculated from vertical displacement: symmetry index (SI), difference between minima (Min......, whereas MinDiff and MaxDiff values are less favourable. Future studies should investigate specific calibration and processing algorithms further improving standalone IMU performance....

  17. Accurate perioperative flow measurement of the portal vein and hepatic and renal artery: A role for preoperative MRI?

    Energy Technology Data Exchange (ETDEWEB)

    Vermeulen, Mechteld A.R., E-mail: mar.vermeulen@vumc.nl [Department of Surgery, VU University Medical Center, P.O. Box 7057, 1007 MB Amsterdam (Netherlands); Ligthart-Melis, Gerdien C., E-mail: g.ligthart-melis@vumc.nl [Department of Internal Medicine, Dietetics and Nutritional Sciences, VU University Medical Center, P.O. Box 7057, 1007 MB Amsterdam (Netherlands); Buijsman, René, E-mail: renebuysman@gmail.com [Department of Surgery, VU University Medical Center, P.O. Box 7057, 1007 MB Amsterdam (Netherlands); Siroen, Michiel P.C., E-mail: m.siroen6@upcmail.nl [Department of Surgery, VU University Medical Center, P.O. Box 7057, 1007 MB Amsterdam (Netherlands); Poll, Marcel C.G. van de, E-mail: mcg.vandepoll@ah.unimaas.nl [Department of Surgery, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ Maastricht (Netherlands); Boelens, Petra G., E-mail: p.boelens@mumc.nl [Department of Surgery, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ Maastricht (Netherlands); Dejong, Cornelis H.C., E-mail: chc.dejong@mumc.nl [Department of Surgery, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ Maastricht (Netherlands); Schaik, Cors van, E-mail: c.vanschaik@vumc.nl [Department of Radiology, VU University Medical Center, P.O. Box 7057, 1007 MB Amsterdam (Netherlands); Hofman, Mark B.M., E-mail: mbm.hofman@vumc.nl [Department of Physics and Medical Technology, VU University Medical Center, P.O. Box 7057, 1007 MB Amsterdam (Netherlands); Leeuwen, Paul A.M. van, E-mail: pam.vleeuwen@vumc.nl [Department of Surgery, VU University Medical Center, P.O. Box 7057, 1007 MB Amsterdam (Netherlands)

    2012-09-15

    Background: Quantification of abdominal blood flow is essential for a variety of gastrointestinal and hepatic topics such as liver transplantation or metabolic flux measurement, but those need to be performed during surgery. It is not clear whether Duplex Doppler Ultrasound during surgery or MRI before surgery is the tool to choose. Objective: To examine whether preoperative evaluation of abdominal blood flow using MRI could prove to be a useful and reliable alternative for the perioperative sonographic approach. Methods: In this study portal and renal venous flow and hepatic arterial flow were sequentially quantified by preoperative MRI, preoperative and perioperative Duplex Doppler Ultrasound (DDUS). 55 Patients scheduled for major abdominal surgery were studied and methods and settings were compared. Additionally, average patient population values were compared. Results: Mean (±SD) plasmaflow measured by perioperative DDUS, preoperative DDUS and MRI, respectively was 433 ± 200/423 ± 162/507 ± 96 ml/min (portal vein); 96 ± 70/74 ± 41/108 ± 91 ml/min (hepatic artery); 248 ± 139/201 ± 118/219 ± 69 ml/min (renal vein). No differences between the different settings of DDUS measurement were detected. Equality of mean was observed for all measurements. Bland Altman Plots showed widespread margins. Hepatic arterial flow measurements correlated with each other, but portal and renal venous flow correlations were absent. Conclusions: Surgery and method (DDUS vs. MRI) do not affect mean flow values. Individual comparison is restricted due to wide range in measurements. Since MRI proves to be more reliable with respect to inter-observer variability, we recommend using mean MRI results in experimental setups.

  18. How accurate are measurements of skin-lesion depths on prebiopsy supine chest computed tomography for transthoracic needle biopsies?

    International Nuclear Information System (INIS)

    Cheung, Joo Yeon; Kim, Yookyung; Shim, Sung Shine; Lee, Jin Hwa; Chang, Jung Hyun; Ryu, Yon Ju; Lee, Rena J.

    2012-01-01

    Aim: To evaluate the accuracy of depth measurements on supine chest computed tomography (CT) for transthoracic needle biopsy (TNB). Materials and methods: We measured skin-lesion depths from the skin surface to nodules on both prebiopsy supine CT scans and CT scans obtained during cone beam CT-guided TNB in the supine (n = 29) or prone (n = 40) position in 69 patients, and analyzed the differences between the two measurements, based on patient position for the biopsy and lesion location. Results: Skin-lesion depths measured on prebiopsy supine CT scans were significantly larger than those measured on CT scans obtained during TNB in the prone position (p < 0.001; mean difference ± standard deviation (SD), 6.2 ± 5.7 mm; range, 0–18 mm), but the differences showed marginal significance in the supine position (p = 0.051; 3.5 ± 3.9 mm; 0–13 mm). Additionally, the differences were significantly larger for the upper (mean ± SD, 7.8 ± 5.7 mm) and middle (10.1 ± 6.5 mm) lung zones than for the lower lung zones (3.1 ± 3.3 mm) in the prone position (p = 0.011), and were larger for the upper lung zone (4.6 ± 5.0 mm) than for the middle (2.4 ± 2.0 mm) and lower (2.3 ± 2.3 mm) lung zones in the supine position (p = 0.004). Conclusions: Skin-lesion depths measured on prebiopsy supine chest CT scans were inaccurate for TNB in the prone position, particularly for nodules in the upper and middle lung zones.

  19. Measurement of longitudinal impedance for a KAON test pipe model with TSD-calibration method

    International Nuclear Information System (INIS)

    Yin, Y.; Oram, C.; Ilinsky, N.; Reinhardt-Nikulin, P.

    1991-05-01

    We report measurements of longitudinal impedances for a KAON factory beam pipe model by means of the TSD-calibration method. The experimental method and the results are discussed. The frequency band is from 48 MHz up to 900 MHz, within which range the method produces measured impedances accurate enough to be useful in indicating whether a test pipe will have a suitably low impedance. (Author) 9 refs., 7 figs

  20. Accurate viscosity measurements of flowing aqueous glucose solutions with suspended scatterers using a dynamic light scattering approach with optical coherence tomography.

    Science.gov (United States)

    Weatherbee, Andrew; Popov, Ivan; Vitkin, Alex

    2017-08-01

    The viscosity of turbid colloidal glucose solutions has been accurately determined from spectral domain optical coherence tomography (OCT) M-mode measurements and our recently developed OCT dynamic light scattering model. Results for various glucose concentrations, flow speeds, and flow angles are reported. The relative "combined standard uncertainty" uc(η) on the viscosity measurements was ±1% for the no-flow case and ±5% for the flow cases, a significant improvement in measurement robustness over previously published reports. The available literature data for the viscosity of pure water and our measurements differ by 1% (stagnant case) and 1.5% (flow cases), demonstrating good accuracy; similar agreement is seen across the measured glucose concentration range when compared to interpolated literature values. The developed technique may contribute toward eventual noninvasive glucose measurements in medicine. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  1. Accurate mitochondrial DNA sequencing using off-target reads provides a single test to identify pathogenic point mutations.

    Science.gov (United States)

    Griffin, Helen R; Pyle, Angela; Blakely, Emma L; Alston, Charlotte L; Duff, Jennifer; Hudson, Gavin; Horvath, Rita; Wilson, Ian J; Santibanez-Koref, Mauro; Taylor, Robert W; Chinnery, Patrick F

    2014-12-01

    Mitochondrial disorders are a common cause of inherited metabolic disease and can be due to mutations affecting mitochondrial DNA or nuclear DNA. The current diagnostic approach involves the targeted resequencing of mitochondrial DNA and candidate nuclear genes, usually proceeds step by step, and is time consuming and costly. Recent evidence suggests that variations in mitochondrial DNA sequence can be obtained from whole-exome sequence data, raising the possibility of a comprehensive single diagnostic test to detect pathogenic point mutations. We compared the mitochondrial DNA sequence derived from off-target exome reads with conventional mitochondrial DNA Sanger sequencing in 46 subjects. Mitochondrial DNA sequences can be reliably obtained using three different whole-exome sequence capture kits. Coverage correlates with the relative amount of mitochondrial DNA in the original genomic DNA sample, heteroplasmy levels can be determined using variant and total read depths, and-providing there is a minimum read depth of 20-fold-rare sequencing errors occur at a rate similar to that observed with conventional Sanger sequencing. This offers the prospect of using whole-exome sequence in a diagnostic setting to screen not only all protein coding nuclear genes but also all mitochondrial DNA genes for pathogenic mutations. Off-target mitochondrial DNA reads can also be used to assess quality control and maternal ancestry, inform on ethnic origin, and allow genetic disease association studies not previously anticipated with existing whole-exome data sets.

  2. Testing the assumption in ergonomics software that overall shoulder strength can be accurately calculated by treating orthopedic axes as independent.

    Science.gov (United States)

    Hodder, Joanne N; La Delfa, Nicholas J; Potvin, Jim R

    2016-08-01

    To predict shoulder strength, most current ergonomics software assume independence of the strengths about each of the orthopedic axes. Using this independent axis approach (IAA), the shoulder can be predicted to have strengths as high as the resultant of the maximum moment about any two or three axes. We propose that shoulder strength is not independent between axes, and propose an approach that calculates the weighted average (WAA) between the strengths of the axes involved in the demand. Fifteen female participants performed maximum isometric shoulder exertions with their right arm placed in a rigid adjustable brace affixed to a tri-axial load cell. Maximum exertions were performed in 24 directions, including four primary directions, horizontal flexion-extension, abduction-adduction, and at 15° increments in between those axes. Moments were computed and comparisons made between the experimentally collected strengths and those predicted by the IAA and WAA methods. The IAA over-predicted strength in 14 of 20 non-primary exertions directions, while the WAA underpredicted strength in only 2 of these directions. Therefore, it is not valid to assume that shoulder axes are independent when predicting shoulder strengths between two orthopedic axes, and the WAA is an improvement over current methods for the posture tested. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Accurate measurement of the piezoelectric coefficient of thin films by eliminating the substrate bending effect using spatial scanning laser vibrometry

    International Nuclear Information System (INIS)

    Leighton, Glenn J T; Huang, Zhaorong

    2010-01-01

    One of the major difficulties in measuring the piezoelectric coefficient d 33,f for thin films is the elimination of the contribution from substrate bending. We show by theoretical analysis and experimental measurements that by bonding thin film piezoelectric samples to a substantial holder, the substrate bending can be minimized to a negligible level. Once the substrate bending can be effectively eliminated, single-beam laser scanning vibrometry can be used to measure the precise strain distribution of a piezoelectric thin film under converse actuation. A significant strain increase toward the inside edge of the top electrode (assuming a fully covered bottom electrode) and a corresponding strain peak in the opposite direction just outside the electrode edge were observed. These peaks were found to increase with the increasing Poisson's ratio and transverse piezoelectric coefficient of the piezoelectric thin film. This is due to the non-continuity of the electric field at the edge of the top electrode, which leads to the concentration of shear stress and electric field in the vicinity of the electrode edge. The measured d 33,f was found to depend not only on the material properties such as the electromechanical coefficients of the piezoelectric thin films and elastic coefficients of the thin film and the substrate, but also on the geometry factors such as the thickness of the piezoelectric films, the dimensions of the electrode, and also the thickness of the substrate

  4. The potential for accurately measuring behavioral and economic dimensions of consumption, prices, and markets for illegal drugs.

    Science.gov (United States)

    Johnson, Bruce D; Golub, Andrew

    2007-09-01

    There are numerous analytic and methodological limitations to current measures of drug market activity. This paper explores the structure of markets and individual user behavior to provide an integrated understanding of behavioral and economic (and market) aspects of illegal drug use with an aim toward developing improved procedures for measurement. This involves understanding the social processes that structure illegal distribution networks and drug users' interactions with them. These networks are where and how social behaviors, prices, and markets for illegal drugs intersect. Our focus is upon getting an up close measurement of these activities. Building better measures of consumption behaviors necessitates building better rapport with subjects than typically achieved with one-time surveys in order to overcome withholding and underreporting and to get a comprehensive understanding of the processes involved. This can be achieved through repeated interviews and observations of behaviors. This paper also describes analytic advances that could be adopted to direct this inquiry including behavioral templates, and insights into the economic valuation of labor inputs and cash expenditures for various illegal drugs. Additionally, the paper makes recommendations to funding organizations for developing the mechanisms that would support behavioral scientists to weigh specimens and to collect small samples for laboratory analysis-by providing protection from the potential for arrest. The primary focus is upon U.S. markets. The implications for other countries are discussed.

  5. Accurate and Integrated Localization System for Indoor Environments Based on IEEE 802.11 Round-Trip Time Measurements

    Directory of Open Access Journals (Sweden)

    Lorenzo RubénMateo

    2010-01-01

    Full Text Available The presence of (Non line of Sight NLOS propagation paths has been considered the main drawback for localization schemes to estimate the position of a (Mobile User MU in an indoor environment. This paper presents a comprehensive wireless localization system based on (Round-Trip Time RTT measurements in an unmodified IEEE 802.11 wireless network. It overcomes the NLOS impairment by implementing the (Prior NLOS Measurements Correction PNMC technique. At first, the RTT measurements are performed with a novel electronic circuit avoiding the need for time synchronization between wireless nodes. At second, the distance between the MU and each reference device is estimated by using a simple linear regression function that best relates the RTT to the distance in (Line of Sight LOS. Assuming that LOS in an indoor environment is a simplification of reality hence, the PNMC technique is applied to correct the NLOS effect. At third, assuming known the position of the reference devices, a multilateration technique is implemented to obtain the MU position. Finally, the localization system coupled with measurements demonstrates that the system outperforms the conventional time-based indoor localization schemes without using any tracking technique such as Kalman filters or Bayesian methods.

  6. Two instruments based on differential optical absorption spectroscopy (DOAS) to measure accurate ammonia concentrations in the atmosphere

    Science.gov (United States)

    Volten, H.; Bergwerff, J. B.; Haaima, M.; Lolkema, D. E.; Berkhout, A. J. C.; van der Hoff, G. R.; Potma, C. J. M.; Wichink Kruit, R. J.; van Pul, W. A. J.; Swart, D. P. J.

    2012-02-01

    We present two Differential Optical Absorption Spectroscopy (DOAS) instruments built at RIVM: the RIVM DOAS and the miniDOAS. Both instruments provide virtually interference-free measurements of NH3 concentrations in the atmosphere, since they measure over an open path, without suffering from inlet problems or interference problems by ammonium aerosols dissociating on tubes or filters. They measure concentrations up to at least 200 μg m-3, have a fast response, low maintenance demands, and a high up-time. The RIVM DOAS has a high accuracy of typically 0.15 μg m-3 for ammonia for 5-min averages and over a total light path of 100 m. The miniDOAS has been developed for application in measurement networks such as the Dutch National Air Quality Monitoring Network (LML). Compared to the RIVM DOAS it has a similar accuracy, but is significantly reduced in size, costs, and handling complexity. The RIVM DOAS and miniDOAS results showed excellent agreement (R2 = 0.996) during a field measurement campaign in Vredepeel, the Netherlands. This measurement site is located in an agricultural area and is characterized by highly variable, but on average high ammonia concentrations in the air. The RIVM-DOAS and miniDOAS results were compared to the results of the AMOR instrument, a continuous-flow wet denuder system, which is currently used in the LML. Averaged over longer time spans of typically a day, the (mini)DOAS and AMOR results agree reasonably well, although an offset of the AMOR values compared to the (mini)DOAS results exists. On short time scales, the (mini)DOAS shows a faster response and does not show the memory effects due to inlet tubing and transport of absorption fluids encountered by the AMOR. Due to its high accuracy, high uptime, low maintenance and its open path, the (mini)DOAS shows a good potential for flux measurements by using two (or more) systems in a gradient set-up and applying the aerodynamic gradient technique.

  7. Two instruments based on differential optical absorption spectroscopy (DOAS to measure accurate ammonia concentrations in the atmosphere

    Directory of Open Access Journals (Sweden)

    H. Volten

    2012-02-01

    Full Text Available We present two Differential Optical Absorption Spectroscopy (DOAS instruments built at RIVM: the RIVM DOAS and the miniDOAS. Both instruments provide virtually interference-free measurements of NH3 concentrations in the atmosphere, since they measure over an open path, without suffering from inlet problems or interference problems by ammonium aerosols dissociating on tubes or filters. They measure concentrations up to at least 200 μg m−3, have a fast response, low maintenance demands, and a high up-time. The RIVM DOAS has a high accuracy of typically 0.15 μg m−3 for ammonia for 5-min averages and over a total light path of 100 m. The miniDOAS has been developed for application in measurement networks such as the Dutch National Air Quality Monitoring Network (LML. Compared to the RIVM DOAS it has a similar accuracy, but is significantly reduced in size, costs, and handling complexity. The RIVM DOAS and miniDOAS results showed excellent agreement (R2 = 0.996 during a field measurement campaign in Vredepeel, the Netherlands. This measurement site is located in an agricultural area and is characterized by highly variable, but on average high ammonia concentrations in the air. The RIVM-DOAS and miniDOAS results were compared to the results of the AMOR instrument, a continuous-flow wet denuder system, which is currently used in the LML. Averaged over longer time spans of typically a day, the (miniDOAS and AMOR results agree reasonably well, although an offset of the AMOR values compared to the (miniDOAS results exists. On short time scales, the (miniDOAS shows a faster response and does not show the memory effects due to inlet tubing and transport of absorption fluids encountered by the AMOR. Due to its high accuracy, high uptime, low maintenance and its open path, the (miniDOAS shows a good potential for flux measurements by using two (or more systems in a gradient set-up and applying the

  8. Test-retest reliability of knee kinematics measurement during gait ...

    African Journals Online (AJOL)

    ACLR) is crucial to minimize the risk of joint degeneration. To achieve this, it is essential that the chosen measurement method can accurately assess knee kinematics and detect the changes in multi-planes of motion. However to date, limited ...

  9. Intelligence is what the intelligence test measures. Seriously

    NARCIS (Netherlands)

    van der Maas, H.L.J.; Kan, K.-J.; Borsboom, D.

    2014-01-01

    The mutualism model, an alternative for the g-factor model of intelligence, implies a formative measurement model in which "g" is an index variable without a causal role. If this model is accurate, the search for a genetic of brain instantiation of "g" is deemed useless. This also implies that the

  10. Axial force measurement for esophageal function testing

    DEFF Research Database (Denmark)

    Gravesen, Flemming Holbæk; Funch-Jensen, Peter; Gregersen, Hans

    2009-01-01

    force (force in radial direction) whereas the bolus moves along the length of esophagus in a distal direction. Force measurements in the longitudinal (axial) direction provide a more direct measure of esophageal transport function. The technique used to record axial force has developed from external...... documented using imaging modalities such as radiography and scintigraphy. This inconsistency using manometry has also been documented by axial force recordings. This underlines the lack of information when diagnostics are based on manometry alone. Increasing the volume of a bag mounted on a probe...

  11. Atom interferometry experiments with lithium. Accurate measurement of the electric polarizability; Experiences d'interferometrie atomique avec le lithium. Mesure de precision de la polarisabilite electrique

    Energy Technology Data Exchange (ETDEWEB)

    Miffre, A

    2005-06-15

    Atom interferometers are very sensitive tools to make precise measurements of physical quantities. This study presents a measurement of the static electric polarizability of lithium by atom interferometry. Our result, {alpha} = (24.33 {+-} 0.16)*10{sup -30} m{sup 3}, improves by a factor 3 the most accurate measurements of this quantity. This work describes the tuning and the operation of a Mach-Zehnder atom interferometer in detail. The two interfering arms are separated by the elastic diffraction of the atomic wave by a laser standing wave, almost resonant with the first resonance transition of lithium atom. A set of experimental techniques, often complicated to implement, is necessary to build the experimental set-up. After a detailed study of the atom source (a supersonic beam of lithium seeded in argon), we present our experimental atom signals which exhibit a very high fringe visibility, up to 84.5 % for first order diffraction. A wide variety of signals has been observed by diffraction of the bosonic isotope at higher diffraction orders and by diffraction of the fermionic less abundant isotope. The quality of these signals is then used to do very accurate phase measurements. A first experiment investigates how the atom interferometer signals are modified by a magnetic field gradient. An absolute measurement of lithium atom electric polarizability is then achieved by applying a static electric field on one of the two interfering arms, separated by only 90 micrometers. The construction of such a capacitor, its alignment in the experimental set-up and its operation are fully detailed.We obtain a very accurate phase measurement of the induced Lo Surdo - Stark phase shift (0.07 % precision). For this first measurement, the final uncertainty on the electric polarizability of lithium is only 0.66 %, and is dominated by the uncertainty on the atom beam mean velocity, so that a further reduction of the uncertainty can be expected. (author)

  12. Mercury flow tests (first report). Wall friction factor measurement tests and future tests plan

    International Nuclear Information System (INIS)

    Kaminaga, Masanori; Kinoshita, Hidetaka; Haga, Katsuhiro; Hino, Ryutaro; Sudo, Yukio

    1999-07-01

    In the neutron science project at JAERI, we plan to inject a pulsed proton beam of a maximum power of 5 MW from a high intense proton accelerator into a mercury target in order to produce high energy neutrons of a magnitude of ten times or more than existing facilities. The neutrons produced by the facility will be utilized for advanced field of science such as the life sciences etc. An urgent issue in order to accomplish this project is the establishment of mercury target technology. With this in mind, a mercury experimental loop with the capacity to circulate mercury up to 15 L/min was constructed to perform thermal hydraulic tests, component tests and erosion characteristic tests. A measurement of the wall friction factor was carried out as a first step of the mercury flow tests, while testing the characteristic of components installed in the mercury loop. This report presents an outline of the mercury loop and experimental results of the wall friction factor measurement. From the wall friction factor measurement, it was made clear that the wettability of the mercury was improved with an increase of the loop operation time and at the same time the wall friction factors were increased. The measured wall friction factors were much lower than the values calculated by the Blasius equation at the beginning of the loop operation because of wall slip caused by a non-wetted condition. They agreed well with the values calculated by the Blasius equation within a deviation of 10% when the sum of the operation time increased more than 11 hours. This report also introduces technical problems with a mercury circulation and future tests plan indispensable for the development of the mercury target. (author)

  13. Optimal Reactive Strength Index: Is It an Accurate Variable to Optimize Plyometric Training Effects on Measures of Physical Fitness in Young Soccer Players?

    Science.gov (United States)

    Ramirez-Campillo, Rodrigo; Alvarez, Cristian; García-Pinillos, Felipe; Sanchez-Sanchez, Javier; Yanci, Javier; Castillo, Daniel; Loturco, Irineu; Chaabene, Helmi; Moran, Jason; Izquierdo, Mikel

    2018-04-01

    Ramirez-Campillo, R, Alvarez, C, García-Pinillos, F, Sanchez-Sanchez, J, Yanci, J, Castillo, D, Loturco, I, Chaabene, H, Moran, J, and Izquierdo, M. Optimal reactive strength index: is it an accurate variable to optimize plyometric training effects on measures of physical fitness in young soccer players? J Strength Cond Res 32(4): 885-893, 2018-This study aimed to compare the effects of drop-jump training using a fixed drop-box height (i.e., 30-cm [FIXED]) vs. an optimal (OPT) drop-box height (i.e., 10-cm to 40-cm: generating an OPT reactive strength index [RSI]) in youth soccer players' physical fitness. Athletes were randomly allocated to a control group (n = 24; age = 13.7 years), a fixed drop-box height group (FIXED, n = 25; age = 13.9 years), or an OPT drop-box height group (OPT, n = 24; age = 13.1 years). Before and after 7 weeks of training, tests for the assessment of jumping (countermovement jump [CMJ], 5 multiple bounds), speed (20-m sprint time), change of direction ability (CODA [Illinois test]), strength {RSI and 5 maximal squat repetition test (5 repetition maximum [RM])}, endurance (2.4-km time trial), and kicking ability (maximal kicking distance) were undertaken. Analyses revealed main effects of time for all dependent variables (p FIXED group (CMJ: 7.4%, d = 0.36; DJ: 19.2%, d = 0.49; CODA: -3.1%, d = -0.21; 5RM: 10.5%, d = 0.32) and the OPT group (CMJ: 16.7%, d = 0.76; DJ: 36.1%, d = 0.79; CODA: -4.4%, d = -0.34; 5RM: 18.1%, d = 0.47). Post hoc analyses also revealed increases for the OPT group in 20-m sprint time (-3.7%, d = 0.27). Therefore, to maximize the effects of plyometric training, an OPT approach is recommended. However, using adequate fixed drop-box heights may provide a rational and practical alternative.

  14. Accurate measurement of 3JHNHα couplings in small or disordered proteins from WATERGATE-optimized TROSY spectra

    Science.gov (United States)

    Bax, Ad

    2015-01-01

    Provided that care is taken in adjusting the WATERGATE element of a 1H-15N TROSY-HSQC experiment, such that neither the water magnetization nor the 1Hα protons are inverted by its final 180° pulse, 3JHNHα couplings can be measured directly from splittings in the 1H dimension of the spectrum. With band-selective 1H decoupling, very high 15N resolution can be achieved. A complete set of 3JHNHα values, ranging from 3.4 to 10.1 Hz was measured for the 56-residue third domain of IgG-binding protein G (GB3). Using the H-N-Cα-Hα dihedral angles extracted from a RDC-refined structure of GB3, 3JHNHα values predicted by a previously parameterized Karplus equation agree to within a root-mean-square deviation (rmsd) of 0.37 Hz with the experimental data. Values measured for the Alzheimer's implicated Aβ1-40 peptide fit to within an rmsd of 0.45 Hz to random coil 3JHNHα values. PMID:26660434

  15. Accurate measurement of (3)J(HNHα) couplings in small or disordered proteins from WATERGATE-optimized TROSY spectra.

    Science.gov (United States)

    Roche, Julien; Ying, Jinfa; Bax, Ad

    2016-01-01

    Provided that care is taken in adjusting the WATERGATE element of a (1)H-(15)N TROSY-HSQC experiment, such that neither the water magnetization nor the (1)H(α) protons are inverted by its final 180° pulse, (3)JHNHα couplings can be measured directly from splittings in the (1)H dimension of the spectrum. With band-selective (1)H decoupling, very high (15)N resolution can be achieved. A complete set of (3)JHNHα values, ranging from 3.4 to 10.1 Hz was measured for the 56-residue third domain of IgG-binding protein G (GB3). Using the H-N-C(α)-H(α) dihedral angles extracted from a RDC-refined structure of GB3, (3)JHNHα values predicted by a previously parameterized Karplus equation agree to within a root-mean-square deviation (rmsd) of 0.37 Hz with the experimental data. Values measured for the Alzheimer's implicated Aβ(1-40) peptide fit to within an rmsd of 0.45 Hz to random coil (3)JHNHα values.

  16. Technical Note: How accurate can stalagmite formation temperatures be determined using vapour bubble radius measurements in fluid inclusions?

    DEFF Research Database (Denmark)

    Spadin, F.; Marti, Dominik; Hidalgo-Staub, R.

    2015-01-01

    -induced vapour bubbles inside the inclusions. A reliable method for precisely measuring the radius of vapour bubbles is presented. The method is applied to stalagmite samples for which the formation temperature is known. An assessment of the bubble radius measurement accuracy and how this error influences......-of-principle investigation that the formation temperature of 10–20 yr old inclusions in a stalagmite taken from the Milandre cave is 9.87 ± 0.80 ◦C, while the mean annual surface temperature, that in the case of the Milandre cave correlates well with the cave temperature, was 9.6 ± 0.15 ◦C, calculated from actual...... measurements at that time, showing a very good agreement. Formation temperatures of inclusions formed during the last 450 yr are found in a temperature range between 8.4 and 9.6 ◦C, which corresponds to the calculated average surface temperature. Paleotemperatures can thus be determined within ±1.0 ◦C....

  17. Assignment of resonances in dissociative recombination of HD{sup +} ions: High-resolution measurements compared with accurate computations

    Energy Technology Data Exchange (ETDEWEB)

    Waffeu Tamo, F. O. [Laboratoire Ondes et Milieux Complexes FRE-3102 CNRS and Universite du Havre, 25, rue Philippe Lebon, BP 540, F-76058 Le Havre (France); Centre for Atomic, Molecular Physics and Quantum Optics (CEPAMOQ), University of Douala, P.O. Box 8580, Douala (Cameroon); Laboratoire d' Etude du Rayonnement et de la Matiere en Astrophysique, Observatoire de Paris, F-91295 Meudon Cedex (France); Buhr, H.; Schwalm, D. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Department of Particle Physics, Weizmann Institute of Science, P.O. Box 26, 76100 Rehovot (Israel); Motapon, O. [LPF, UFD Physique et Sciences de l' Ingenieur, University of Douala, P.O. Box 24157, Douala (Cameroon); Altevogt, S.; Andrianarijaona, V. M.; Grieser, M.; Lammich, L.; Lestinsky, M.; Motsch, M.; Novotny, S.; Orlov, D. A.; Pedersen, H. B.; Sprenger, F.; Weigel, U.; Wolf, A. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany); Nevo, I. [Department of Particle Physics, Weizmann Institute of Science, P.O. Box 26, 76100 Rehovot (Israel); Urbain, X. [Institute of Condensed Matter and Nanosciences, Universite catholique de Louvain, chemin du cyclotron 2, B-1348 Louvain-la Neuve (Belgium); Schneider, I. F. [Laboratoire Ondes et Milieux Complexes FRE-3102 CNRS and Universite du Havre, 25, rue Philippe Lebon, BP 540, F-76058 Le Havre (France)

    2011-08-15

    The collision-energy resolved rate coefficient for dissociative recombination of HD{sup +} ions in the vibrational ground state is measured using the photocathode electron target at the heavy-ion storage ring TSR. Rydberg resonances associated with rovibrational excitation of the HD{sup +} core are scanned as a function of the electron collision energy with an instrumental broadening below 1 meV in the low-energy limit. The measurement is compared to calculations using multichannel quantum defect theory, accounting for rotational structure and interactions and considering the six lowest rotational energy levels as initial ionic states. Using thermal-equilibrium-level populations at 300 K to approximate the experimental conditions, close correspondence between calculated and measured structures is found up to the first vibrational excitation threshold of the cations near 0.24 eV. Detailed assignments, including naturally broadened and overlapping Rydberg resonances, are performed for all structures up to 0.024 eV. Resonances from purely rotational excitation of the ion core are found to have similar strengths as those involving vibrational excitation. A dominant low-energy resonance is assigned to contributions from excited rotational states only. The results indicate strong modifications in the energy dependence of the dissociative recombination rate coefficient through the rotational excitation of the parent ions, and underline the need for studies with rotationally cold species to obtain results reflecting low-temperature ionized media.

  18. Accurate and stable equal-pressure measurements of water vapor transmission rate reaching the 10-6 g m-2 day-1 range

    Science.gov (United States)

    Nakano, Yoichiro; Yanase, Takashi; Nagahama, Taro; Yoshida, Hajime; Shimada, Toshihiro

    2016-10-01

    The water vapor transmission rate (WVTR) of a gas barrier coating is a critically important parameter for flexible organic device packaging, but its accurate measurement without mechanical stress to ultrathin films has been a significant challenge in instrumental analysis. At the current stage, no reliable results have been reported in the range of 10-6 g m-2 day-1 that is required for organic light emitting diodes (OLEDs). In this article, we describe a solution for this difficult, but important measurement, involving enhanced sensitivity by a cold trap, stabilized temperature system, pumped sealing and calibration by a standard conductance element.

  19. Combining Blink, Pupil, and Response Time Measures in a Concealed Knowledge Test

    Directory of Open Access Journals (Sweden)

    Travis eSeymour

    2013-02-01

    Full Text Available The response time (RT based Concealed Knowledge Test (CKT has been shown to accurately detect participants’ knowledge of mock-crime related information. Tests based on ocular measures such as pupil size and blink rate have sometimes resulted in poor classification, or lacked detailed classification analyses. The present study examines the fitness of multiple pupil and blink related responses in the CKT paradigm. To maximize classification efficiency, participants’ concealed knowledge was assessed using both individual test measures and combinations of test measures. Results show that individual pupil-size, pupil-slope, and pre-response blink-rate measures produce efficient classifications. Combining pupil and blink measures yielded more accuracy classifications than individual ocular measures. Although RT-based tests proved efficient, combining RT with ocular measures had little incremental benefit. It is argued that covertly assessing ocular measures during RT-based tests may guard against effective countermeasure use in applied settings. A compound classification procedure was used to categorize individual participants and yielded high hit rates and low false-alarm rates without the need for adjustments between test paradigms or subject populations. We conclude that with appropriate test paradigms and classification analyses, ocular measures may prove as effective as other indices, though additional research is needed.

  20. An accurate projector gamma correction method for phase-measuring profilometry based on direct optical power detection

    Science.gov (United States)

    Liu, Miao; Yin, Shibin; Yang, Shourui; Zhang, Zonghua

    2015-10-01

    Digital projector is frequently applied to generate fringe pattern in phase calculation-based three dimensional (3D) imaging systems. Digital projector often works with camera in this kind of systems so the intensity response of a projector should be linear in order to ensure the measurement precision especially in Phase-Measuring Profilometry (PMP). Some correction methods are often applied to cope with the non-linear intensity response of the digital projector. These methods usually rely on camera and gamma function is often applied to compensate the non-linear response so the correction performance is restricted by the dynamic range of camera. In addition, the gamma function is not suitable to compensate the nonmonotonicity intensity response. This paper propose a gamma correction method by the precisely detecting the optical energy instead of using a plate and camera. A photodiode with high dynamic range and linear response is used to directly capture the light optical from the digital projector. After obtaining the real gamma curve precisely by photodiode, a gray level look-up table (LUT) is generated to correct the image to be projected. Finally, this proposed method is verified experimentally.

  1. An Investigation into the Required Equipment and Procedures for the Accurate Measurement of Pressure in Hydraulic Fluid Power Systems

    Science.gov (United States)

    1976-05-27

    Q(GPM) Q(GPM) Q(;PM) Q(GPM) Q(GPM) 50 .00157 .00190 .0163 .0128 .0216 . 0235 .272 .0252 100 .00297 .00386 .0290 .0231 .0377 .C40S .C572 0.477 AP gaugr...using HP -SS programmable calculator and the program given below. 01 R/S OS f 02 f 06 log1 0 03 log 1 07 E 04 R/S 08 GOTO-01 -22 - After all values of P...the 32 inch long, 1/2 inch seamless steel tubing was installed into the FPI 190 HP test cell number three pump supply line (see Figure 1.3.1.2.2.2). The

  2. Does Pelletizing Catalysts Influence the Efficiency Number of Activity Measurements? Spectrochemical Engineering Considerations for an Accurate Operando Study

    DEFF Research Database (Denmark)

    Rasmussen, Søren Birk; Perez-Ferreras, Susana; Banares, Miguel A.

    2013-01-01

    of, for example, support oxides might take place, which in turn affects the pore size distribution and the porosity of the catalyst, leading to the observation of lower activity values due to decreased catalyst efficiency. This phenomenon can also apply to conventional activity measurements......, in the cases that pelletizing and recrushing of samples are performed to obtain adequate particle size fractions for the catalytic bed. A case study of an operand investigation of a V2O3-WO3/TiO2-sepiolite catalyst is used as an example, and simple calculations of the influence of catalyst activity...... and internal pore diffusion properties are considered in this paper for the evaluation of catalyst performance in, for example, operando reactors. Thus, it is demonstrated that with a pelletizing pressure of...

  3. Accurate kinematic measurement at interfaces between dissimilar materials using conforming finite-element-based digital image correlation

    KAUST Repository

    Tao, Ran

    2016-02-11

    Digital image correlation (DIC) is now an extensively applied full-field measurement technique with subpixel accuracy. A systematic drawback of this technique, however, is the smoothening of the kinematic field (e.g., displacement and strains) across interfaces between dissimilar materials, where the deformation gradient is known to be large. This can become an issue when a high level of accuracy is needed, for example, in the interfacial region of composites or joints. In this work, we described the application of global conforming finite-element-based DIC technique to obtain precise kinematic fields at interfaces between dissimilar materials. Speckle images from both numerical and actual experiments processed by the described global DIC technique better captured sharp strain gradient at the interface than local subset-based DIC. © 2016 Elsevier Ltd. All rights reserved.

  4. Highly accurate nuclear and electronic stopping cross sections derived using Monte Carlo simulations to reproduce measured range data

    Science.gov (United States)

    Wittmaack, Klaus; Mutzke, Andreas

    2017-03-01

    We have examined and confirmed the previously unexplored concept of using Monte Carlo calculations in combination with measured projected ranges of ions implanted in solids to derive a quantitative description of nuclear interaction and electronic stopping. The study involved 98 ranges of 11B in Si between 1 keV and 8 MeV, contained in 12 sets of 10 different groups. Systematic errors by up to ±8% were removed to establish a refined data base with 93 ranges featuring only statistical uncertainties (±1.8%). The Monte Carlo calculations could be set up to reproduce the refined ranges with a mean ratio 1.002 ± 1.7%. The input parameters required for this very high level of agreement are as follows. Nuclear interaction is best described by the Kr-C potential, but in obligatory combination with the Lindhard-Scharff (LS) screening length. Up to 300 keV, the electronic stopping cross section is proportional to the projectile velocity, Se = kSe,LS, with k = 1.46 ± 0.01. At higher energies, Se falls progressively short of kSe,LS. Around the Bragg peak, i.e., between 0.8 and 10 MeV, Se is modeled by an adjustable function serving to tailor the peak shape properly. Calculated and measured isotope effects for ranges of 10B and 11B in Si agree within the experimental uncertainty (±0.25%). The range-based Se,R(E) reported here predicts the scarce experimental data derived from the energy loss in projectile transmission through thin Si foils to within 2% or better. By contrast, Se(E) data of available stopping power tables exhibit deviations from Se,R(E) between -40% and +14%.

  5. Tumor volume in subcutaneous mouse xenografts measured by microCT is more accurate and reproducible than determined by 18F-FDG-microPET or external caliper.

    Science.gov (United States)

    Jensen, Mette Munk; Jørgensen, Jesper Tranekjaer; Binderup, Tina; Kjaer, Andreas

    2008-10-16

    In animal studies tumor size is used to assess responses to anticancer therapy. Current standard for volumetric measurement of xenografted tumors is by external caliper, a method often affected by error. The aim of the present study was to evaluate if microCT gives more accurate and reproducible measures of tumor size in mice compared with caliper measurements. Furthermore, we evaluated the accuracy of tumor volume determined from 18F-fluorodeoxyglucose (18F-FDG) PET. Subcutaneously implanted human breast adenocarcinoma cells in NMRI nude mice served as tumor model. Tumor volume (n = 20) was determined in vivo by external caliper, microCT and 18F-FDG-PET and subsequently reference volume was determined ex vivo. Intra-observer reproducibility of the microCT and caliper methods were determined by acquiring 10 repeated volume measurements. Volumes of a group of tumors (n = 10) were determined independently by two observers to assess inter-observer variation. Tumor volume measured by microCT, PET and caliper all correlated with reference volume. No significant bias of microCT measurements compared with the reference was found, whereas both PET and caliper had systematic bias compared to reference volume. Coefficients of variation for intra-observer variation were 7% and 14% for microCT and caliper measurements, respectively. Regression coefficients between observers were 0.97 for microCT and 0.91 for caliper measurements. MicroCT was more accurate than both caliper and 18F-FDG-PET for in vivo volumetric measurements of subcutaneous tumors in mice.18F-FDG-PET was considered unsuitable for determination of tumor size. External caliper were inaccurate and encumbered with a significant and size dependent bias. MicroCT was also the most reproducible of the methods.

  6. [11C]Flumazenil metabolite measurement in plasma is not necessary for accurate brain benzodiazepine receptor quantification

    International Nuclear Information System (INIS)

    Sanabria-Bohorquez, S.M.; Veraart, C.; Labar, D.; Bol, A.; Volder, A.G. de; Michel, C.; Leveque, P.

    2000-01-01

    In this work, a mathematical correction for metabolites has been validated which estimates the relative amount of [ 11 C]flumazenil ([ 11 C]FMZ) in the total plasma curve from the tissue kinetic data without the need for direct metabolite measurement in blood plasma samples. Kinetic data were obtained using a 90-min three-injection protocol on five normal volunteers. First, the relative amount of [ 11 C]FMZ in plasma was modelled by a two-parameter exponential function. The parameters were estimated either directly by fitting this model to the blood plasma metabolite measurements, or indirectly from the simultaneous fitting of tissue time activity curves from several brain regions with a non-linear FMZ kinetic model. Second, the direct and indirect metabolite corrections were fixed and the FMZ compartmental parameters were determined on a regional basis in the brain. The validation was performed by comparing the regional values of benzodiazepine receptor density B max and equilibrium dissociation constant K d obtained with the direct metabolite correction with those values obtained with the indirect correction. For B max , the correlation coefficient r 2 was above 0.97 for all subjects and the slope values of the linear regression were within the interval [0.97, 1.2]. For K d , r 2 was above 0.96, and the slope values of the linear regression were within the interval [0.99, 1.1]. Simulation studies were performed in order to evaluate whether this metabolite correction method could be used in a clinical protocol where only a single [ 11 C]FMZ injection and a linear compartmental model are used. The resulting [ 11 C]FMZ distribution volume estimates were found to be linearly correlated with the true values, with r 2 =1.0 and a slope value of 1.1. The mathematical metabolite correction proved to be a feasible and reliable method to estimate the relative amount of [ 11 C]FMZ in plasma and the compartmental model parameters for three-injection protocols. Although

  7. Compensation of Unavailable Test Frequencies During Immunity Measurements

    Science.gov (United States)

    Gronwald, F.; Kebel, R.; Stadtler, T.

    2012-05-01

    Radiated immunity tests usually are performed in shielded test environments, such as anechoic chambers, GTEM-cells, and mode stirred chambers, for example. Then, if testing is performed in the frequency domain, the corresponding EMC-standards often specify test frequencies that have to be used. These requirements may become incompatible in case of large test objects, such as passenger aircraft, that cannot be placed in shielded test environments but only can be tested in open environments where, for regulatory reasons, not all required test frequencies can be applied. In this contribution it is investigated whether incomplete test procedures due to unavailable test frequencies can be compensated by alternative measurement setups.

  8. Accurate and precise measurement of oxygen isotopic fractions and diffusion profiles by selective attenuation of secondary ions (SASI).

    Science.gov (United States)

    Téllez, Helena; Druce, John; Hong, Jong-Eun; Ishihara, Tatsumi; Kilner, John A

    2015-03-03

    The accuracy and precision of isotopic analysis in Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) relies on the appropriate reduction of the dead-time and detector saturation effects, especially when analyzing species with high ion yields or present in high concentrations. Conventional approaches to avoid these problems are based on Poisson dead-time correction and/or an overall decrease of the total secondary ion intensity by reducing the target current. This ultimately leads to poor detection limits for the minor isotopes and high uncertainties of the measured isotopic ratios. An alternative strategy consists of the attenuation of those specific secondary ions that saturate the detector, providing an effective extension of the linear dynamic range. In this work, the selective attenuation of secondary ion signals (SASI) approach is applied to the study of oxygen transport properties in electroceramic materials by isotopic labeling with stable (18)O tracer and ToF-SIMS depth profiling. The better analytical performance in terms of accuracy and precision allowed a more reliable determination of the oxygen surface exchange and diffusion coefficients while maintaining good mass resolution and limits of detection for other minor secondary ion species. This improvement is especially relevant to understand the ionic transport mechanisms and properties of solid materials, such as the parallel diffusion pathways (e.g., oxygen diffusion through bulk, grain boundary, or dislocations) in electroceramic materials with relevant applications in energy storage and conversion devices.

  9. Tumor volume in subcutaneous mouse xenografts measured by microCT is more accurate and reproducible than determined by 18F-FDG-microPET or external caliper

    DEFF Research Database (Denmark)

    Jensen, Mette Munk; Jørgensen, Jesper Tranekjaer; Binderup, Tina

    2008-01-01

    BACKGROUND: In animal studies tumor size is used to assess responses to anticancer therapy. Current standard for volumetric measurement of xenografted tumors is by external caliper, a method often affected by error. The aim of the present study was to evaluate if microCT gives more accurate...... and reproducible measures of tumor size in mice compared with caliper measurements. Furthermore, we evaluated the accuracy of tumor volume determined from 18F-fluorodeoxyglucose (18F-FDG) PET. METHODS: Subcutaneously implanted human breast adenocarcinoma cells in NMRI nude mice served as tumor model. Tumor volume...... (n = 20) was determined in vivo by external caliper, microCT and 18F-FDG-PET and subsequently reference volume was determined ex vivo. Intra-observer reproducibility of the microCT and caliper methods were determined by acquiring 10 repeated volume measurements. Volumes of a group of tumors (n = 10...

  10. Method for independent strain and temperature measurement in polymeric tensile test specimen using embedded FBG sensors

    DEFF Research Database (Denmark)

    Pereira, Gilmar Ferreira; McGugan, Malcolm; Mikkelsen, Lars Pilgaard

    2016-01-01

    to calculate independently the strain and temperature are presented in the article, together with a measurement resolution study. This multi-parameter measurement method was applied to an epoxy tensile specimen, tested in a unidirectional tensile test machine with a temperature controlled cabinet. A full......A novel method to obtain independent strain and temperature measurements using embedded Fibre Bragg Grating (FBG) in polymeric tensile test specimens is presented in this paper. The FBG strain and temperature cross-sensitivity was decoupled using two single mode FBG sensors, which were embedded...... of temperature, from 40 C to -10 C. The consistency of the expected theoretical results with the calibration procedure and the experimental validation shows that this proposed method is applicable to measure accurate strain and temperature in polymers during static or fatigue tensile testing. Two different...

  11. Bending Under Tension Test with Direct Friction Measurement

    DEFF Research Database (Denmark)

    Andreasen, Jan Lasson; Olsson, David Dam; Chodnikiewicz, K.

    2004-01-01

    A special BUT-transducer has been developed in which friction around the tool radius can be directly measured when drawing a plane sheet strip around a cylindrical tool-pin under constant back tension. The front tension, back tension and torque on the tool-pin are all measured directly, thus...... enabling accurate measurement of friction and direct determination of lubricant film breakdown for varying normal pressure, sliding speed, tool radius and tool preheat temperature. The transducer is applied in an experimental investigation focusing on limits of lubrication in drawing of stainless steel...

  12. Bending Under Tension Test with Direct Friction Measurement

    DEFF Research Database (Denmark)

    Andreasen, Jan Lasson; Olsson, David Dam; Chodnikiewicz, K.

    2006-01-01

    A special Bending-Under-Tension (BUT) transducer has been developed in which friction around the tool radius can be directly measured when drawing a plane sheet strip around a cylindrical tool-pin under constant back tension. The front tension, back tension and torque on the tool-pin are all...... measured directly, thus enabling accurate measurement of friction and direct determination of lubricant film breakdown for varying normal pressure, sliding speed, tool radius and tool preheat temperature. The transducer is applied in an experimental investigation focusing on limits of lubrication...... in drawing of stainless steel showing the influence of varying process conditions and the performance of different lubricants....

  13. Test device for measuring permeability of a barrier material

    Science.gov (United States)

    Reese, Matthew; Dameron, Arrelaine; Kempe, Michael

    2014-03-04

    A test device for measuring permeability of a barrier material. An exemplary device comprises a test card having a thin-film conductor-pattern formed thereon and an edge seal which seals the test card to the barrier material. Another exemplary embodiment is an electrical calcium test device comprising: a test card an impermeable spacer, an edge seal which seals the test card to the spacer and an edge seal which seals the spacer to the barrier material.

  14. The need for accurate long-term measurements of water vapor in the upper troposphere and lower stratosphere with global coverage

    Science.gov (United States)

    Müller, Rolf; Kunz, Anne; Hurst, Dale F.; Rolf, Christian; Krämer, Martina; Riese, Martin

    2016-02-01

    Water vapor is the most important greenhouse gas in the atmosphere although changes in carbon dioxide constitute the "control knob" for surface temperatures. While the latter fact is well recognized, resulting in extensive space-borne and ground-based measurement programs for carbon dioxide as detailed in the studies by Keeling et al. (1996), Kuze et al. (2009), and Liu et al. (2014), the need for an accurate characterization of the long-term changes in upper tropospheric and lower stratospheric (UTLS) water vapor has not yet resulted in sufficiently extensive long-term international measurement programs (although first steps have been taken). Here, we argue for the implementation of a long-term balloon-borne measurement program for UTLS water vapor covering the entire globe that will likely have to be sustained for hundreds of years.

  15. Atomic spectroscopy and highly accurate measurement: determination of fundamental constants; Spectroscopie atomique et mesures de grande precision: determination de constantes fonfamentales

    Energy Technology Data Exchange (ETDEWEB)

    Schwob, C

    2006-12-15

    This document reviews the theoretical and experimental achievements of the author concerning highly accurate atomic spectroscopy applied for the determination of fundamental constants. A pure optical frequency measurement of the 2S-12D 2-photon transitions in atomic hydrogen and deuterium has been performed. The experimental setting-up is described as well as the data analysis. Optimized values for the Rydberg constant and Lamb shifts have been deduced (R = 109737.31568516 (84) cm{sup -1}). An experiment devoted to the determination of the fine structure constant with an aimed relative uncertainty of 10{sup -9} began in 1999. This experiment is based on the fact that Bloch oscillations in a frequency chirped optical lattice are a powerful tool to transfer coherently many photon momenta to the atoms. We have used this method to measure accurately the ratio h/m(Rb). The measured value of the fine structure constant is {alpha}{sub -1} = 137.03599884 (91) with a relative uncertainty of 6.7*10{sup -9}. The future and perspectives of this experiment are presented. This document presented before an academic board will allow his author to manage research work and particularly to tutor thesis students. (A.C.)

  16. Accurate measurements of fission-fragment yields in 234,235,236,238U(γ,f) with the SOFIA set-up

    International Nuclear Information System (INIS)

    Chatillon, A.; Taieb, J.; Martin, J.F.; Pellereau, E.; Boutoux, G.; Gorbinet, T.; Grente, L.; Belier, G.; Laurent, B.; Alvarez-Pol, H.; Ayyad, Y.; Benlliure, J.; Caamano, M.; Cortina-Gil, D.; Fernandez-Dominguez, B.; Paradela, C.; Ramos, D.; Rodriguez-Sanchez, J.L.; Vargas, J.; Audouin, L.; Tassan-Got, L.; Yan, Y.; Casarejos, E.; Farget, F.; Rodriguez-Tajes, C.; Heinz, A.; Lindberg, S.; Jurado, B.; Kelic-Heil, A.; Kurz, N.; Loeher, B.; Nociforo, C.; Pietri, S.; Rossi, D.; Schmidt, K.H.; Simon, H.; Voss, B.; Weick, H.; Toernqvist, H.

    2016-01-01

    SOFIA (Studies On Fission with Aladin) is a new experimental set-up dedicated to accurate measurement of fission-fragments isotopic yields. It is located at GSI, the only place to use inverse kinematics at relativistic energies in order to study the (γ,f) electromagnetic-induced fission. The SOFIA set-up is a large-acceptance magnetic spectrometer, which allows to fully identify both fission fragments in coincidence on the whole fission-fragment range. This paper will report on fission yields obtained in 234,235,236,238 U(γ,f) reactions. (authors)

  17. Heart Rate Measures of Flight Test and Evaluation

    National Research Council Canada - National Science Library

    Bonner, Malcolm A; Wilson, Glenn F

    2001-01-01

    .... Because flying is a complex task, several measures are required to derive the best evaluation. This article describes the use of heart rate to augment the typical performance and subjective measures used in test and evaluation...

  18. Reducing measurement errors during functional capacity tests in elders.

    Science.gov (United States)

    da Silva, Mariane Eichendorf; Orssatto, Lucas Bet da Rosa; Bezerra, Ewertton de Souza; Silva, Diego Augusto Santos; Moura, Bruno Monteiro de; Diefenthaeler, Fernando; Freitas, Cíntia de la Rocha

    2017-08-23

    Accuracy is essential to the validity of functional capacity measurements. To evaluate the error of measurement of functional capacity tests for elders and suggest the use of the technical error of measurement and credibility coefficient. Twenty elders (65.8 ± 4.5 years) completed six functional capacity tests that were simultaneously filmed and timed by four evaluators by means of a chronometer. A fifth evaluator timed the tests by analyzing the videos (reference data). The means of most evaluators for most tests were different from the reference (p error of measurement between tests and evaluators. The Bland-Altman test showed difference in the concordance of the results between methods. Short duration tests showed higher technical error of measurement than longer tests. In summary, tests timed by a chronometer underestimate the real results of the functional capacity. Difference between evaluators' reaction time and perception to determine the start and the end of the tests would justify the errors of measurement. Calculation of the technical error of measurement or the use of the camera can increase data validity.

  19. Measurement properties of continuous text reading performance tests

    NARCIS (Netherlands)

    Verkerk-Brussee, T.; van Nispen, R.M.A.; van Rens, G.H.M.B.

    2014-01-01

    Purpose: Measurement properties of tests to assess reading acuity or reading performance have not been extensively evaluated. This study aims to provide an overview of the literature on available continuous text reading tests and their measurement properties. Methods: A literature search was

  20. Four Square Step Test With Foam is More Accurate Than Those Without Foam for Discriminating Between Older Adults With and Without Fall History.

    Science.gov (United States)

    Mathurapongsakul, Phakkanut; Siriphorn, Akkradate

    2018-02-12

    The aim was to compare the use of the four square step test (FSST) and the four square step test with foam surface (FSST+foam) scores for discriminating between adults, faller older adults, and non-faller older adults. Fifty-four participants (18 for each group) were assessed using the FSST and FSST+foam. The area under the curve (AUC) of receiver operating characteristic curve was calculated and used to compare the accuracy of the tests. The FSST+foam was more accurate than FSST for discriminating between faller and non-faller older adults (AUCs were 0.765 and 0.725, respectively.) and between non-faller older adults and adults (AUCs were 0.99 and 0.95, respectively.). The cutoff score for discriminating between faller and non-faller older adults was 11.21, with sensitivity and specificity of 0.889 and 0.611, respectively. FSST+foam could be used as an alternative assessment for discriminating between adults, faller and non-faller older adults.

  1. Time-accurate CFD conjugate analysis of transient measurements of the heat-transfer coefficient in a channel with pin fins

    Directory of Open Access Journals (Sweden)

    Tom I-P. Shih

    2013-03-01

    Full Text Available Heat-transfer coefficients (HTC on surfaces exposed to convection environments are often measured by transient techniques such as thermochromic liquid crystal (TLC or infrared thermography. In these techniques, the surface temperature is measured as a function of time, and that measurement is used with the exact solution for unsteady, zero-dimensional (0-D or one-dimensional (1-D heat conduction into a solid to calculate the local HTC. When using the 0-D or 1-D exact solutions, the transient techniques assume the HTC and the free-stream or bulk temperature characterizing the convection environment to be constants in addition to assuming the conduction into the solid to be 0-D or 1-D. In this study, computational fluid dynamics (CFD conjugate analyses were performed to examine the errors that might be invoked by these assumptions for a problem, where the free-stream/bulk temperature and the heat-transfer coefficient vary appreciably along the surface and where conduction into the solid may not be 0-D or 1-D. The problem selected to assess these errors is flow and heat transfer in a channel lined with a staggered array of pin fins. This conjugate study uses three-dimensional (3-D unsteady Reynolds-averaged Navier–Stokes (RANS closed by the shear-stress transport (SST turbulence model for the gas phase (wall functions not used and the Fourier law for the solid phase. The errors in the transient techniques are assessed by comparing the HTC predicted by the time-accurate conjugate CFD with those predicted by the 0-D and 1-D exact solutions, where the surface temperatures needed by the exact solutions are taken from the time-accurate conjugate CFD solution. Results obtained show that the use of the 1-D exact solution for the semi-infinite wall to give reasonably accurate “transient” HTC (less than 5% relative error. Transient techniques that use the 0-D exact solution for the pin fins were found to produce large errors (up to 160% relative error

  2. Measurement error in pressure-decay leak testing

    International Nuclear Information System (INIS)

    Robinson, J.N.

    1979-04-01

    The effect of measurement error in presssure-decay leak testing is considered, and examples are presented to demonstrate how it can be properly accomodated in analyzing data from such tests. Suggestions for more effective specification and conduct of leak tests are presented

  3. Total Cross Sections as a Surrogate for Neutron Capture: An Opportunity to Accurately Constrain (n,γ) Cross Sections for Nuclides Beyond the Reach of Direct Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Koehler, Paul E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-03-05

    There are many (n,γ) cross sections of great interest to radiochemical diagnostics and to nuclear astrophysics which are beyond the reach of current measurement techniques, and likely to remain so for the foreseeable future. In contrast, total neutron cross sections currently are feasible for many of these nuclides and provide almost all the information needed to accurately calculate the (n,γ) cross sections via the nuclear statistical model (NSM). I demonstrate this for the case of 151Sm; NSM calculations constrained using average resonance parameters obtained from total cross section measurements made in 1975, are in excellent agreement with recent 151Sm (n,γ) measurements across a wide range of energy. Furthermore, I demonstrate through simulations that total cross section measurements can be made at the Manuel Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center for samples as small as 10μg. Samples of this size should be attainable for many nuclides of interest. Finally, I estimate that over half of the radionuclides identified ~20 years ago as having (n,γ) cross sections of importance to s-process nucleosynthesis studies (24/43) and radiochemical diagnostics (11/19), almost none of which have been measured, can be constrained using this technique.

  4. An accurate measurement of the anisotropies and mean level of the cosmic infrared background at 100 μm and 160 μm

    Science.gov (United States)

    Pénin, A.; Lagache, G.; Noriega-Crespo, A.; Grain, J.; Miville-Deschênes, M.-A.; Ponthieu, N.; Martin, P.; Blagrave, K.; Lockman, F. J.

    2012-07-01

    Context. The measurement of the anisotropies in the cosmic infrared background (CIB) is a powerful means of studying the evolution of galaxies and large-scale structures. These anisotropies have been measured by a number of experiments, from the far-infrared (AKARI 90 μm) to the millimeter (Planck and the South Pole Telescope at ~2 mm). One of the main impediments to an accurate measurement on large scales ( ≲ 1 degree) is the contamination of the foreground signal by Galactic dust emission. Aims: Our goal is to show that we can remove the Galactic cirrus contamination using Hi data, and thus accurately measure the clustering of starburst galaxies in the CIB. Methods: We use observations of the so-called extragalactic ELAIS N1 field at far-infrared (100 and 160 μm) and radio (21 cm) wavelengths. We compute the correlation between dust emission, traced by far-infrared observations, and Hi gas traced by 21 cm observations, and derive dust emissivities that enable us to subtract the cirrus emission from the far-infrared maps. We then derive the power spectrum of the CIB anisotropies, as well as its mean level at 100 μm and 160 μm. Results: We compute dust emissivities for each of the Hi-velocity components (local, intermediate, and high velocity). Using IRIS/IRAS data at 100 μm, we demonstrate that we can use the measured emissivities to determine and remove the cirrus contribution to the power spectrum of the CIB on large angular scales where the cirrus contribution dominates. We then apply this method to Spitzer/MIPS data for 160 μm. We measure correlated anisotropies at 160 μm, and for the first time at 100 μm. We also combine the Hi data and Spitzer total power mode absolute measurements to determine the CIB mean level at 160 μm. We find B160 = 0.77 ± 0.04 ± 0.12 MJy/sr, where the first error is statistical and the second one systematic. Combining this measurement with the B100/B160 color of the correlated anisotropies, we also derive the CIB mean at

  5. A New Position Measurement System Using a Motion-Capture Camera for Wind Tunnel Tests

    Directory of Open Access Journals (Sweden)

    Yousok Kim

    2013-09-01

    Full Text Available Considering the characteristics of wind tunnel tests, a position measurement system that can minimize the effects on the flow of simulated wind must be established. In this study, a motion-capture camera was used to measure the displacement responses of structures in a wind tunnel test, and the applicability of the system was tested. A motion-capture system (MCS could output 3D coordinates using two-dimensional image coordinates obtained from the camera. Furthermore, this remote sensing system had some flexibility regarding lab installation because of its ability to measure at relatively long distances from the target structures. In this study, we performed wind tunnel tests on a pylon specimen and compared the measured responses of the MCS with the displacements measured with a laser displacement sensor (LDS. The results of the comparison revealed that the time-history displacement measurements from the MCS slightly exceeded those of the LDS. In addition, we confirmed the measuring reliability of the MCS by identifying the dynamic properties (natural frequency, damping ratio, and mode shape of the test specimen using system identification methods (frequency domain decomposition, FDD. By comparing the mode shape obtained using the aforementioned methods with that obtained using the LDS, we also confirmed that the MCS could construct a more accurate mode shape (bending-deflection mode shape with the 3D measurements.

  6. Accurate measurements and temperature dependence of the water vapor self-continuum absorption in the 2.1 μm atmospheric window

    International Nuclear Information System (INIS)

    Ventrillard, I.; Romanini, D.; Mondelain, D.; Campargue, A.

    2015-01-01

    In spite of its importance for the evaluation of the Earth radiative budget, thus for climate change, very few measurements of the water vapor continuum are available in the near infrared atmospheric windows especially at temperature conditions relevant for our atmosphere. In addition, as a result of the difficulty to measure weak broadband absorption signals, the few available measurements show large disagreements. We report here accurate measurements of the water vapor self-continuum absorption in the 2.1 μm window by Optical Feedback Cavity Enhanced Absorption Spectroscopy (OF-CEAS) for two spectral points located at the low energy edge and at the center of the 2.1 μm transparency window, at 4302 and 4723 cm −1 , respectively. Self-continuum cross sections, C S , were retrieved with a few % relative uncertainty, from the quadratic dependence of the spectrum base line level measured as a function of water vapor pressure, between 0 and 16 Torr. At 296 K, the C S value at 4302 cm −1 is found 40% higher than predicted by the MT-CKD V2.5 model, while at 4723 cm −1 , our value is 5 times larger than the MT-CKD value. On the other hand, these OF-CEAS C S values are significantly smaller than recent measurements by Fourier transform spectroscopy at room temperature. The temperature dependence of the self-continuum cross sections was also investigated for temperatures between 296 K and 323 K (23-50 °C). The derived temperature variation is found to be similar to that derived from previous Fourier transform spectrometer (FTS) measurements performed at higher temperatures, between 350 K and 472 K. The whole set of measurements spanning the 296-472 K temperature range follows a simple exponential law in 1/T with a slope close to the dissociation energy of the water dimer, D 0 ≈ 1100 cm −1

  7. Mycobacterial genomic DNA from used Xpert MTB/RIF cartridges can be utilised for accurate second-line genotypic drug susceptibility testing and spoligotyping.

    Science.gov (United States)

    Venter, Rouxjeane; Derendinger, Brigitta; de Vos, Margaretha; Pillay, Samantha; Dolby, Tanya; Simpson, John; Kitchin, Natasha; Ruiters, Ashley; van Helden, Paul D; Warren, Robin M; Theron, Grant

    2017-11-01

    Xpert MTB/RIF (Xpert) is a widely-used test for tuberculosis (TB) and rifampicin-resistance. Second-line drug susceptibility testing (DST), which is recommended by policymakers, typically requires additional specimen collection that delays effective treatment initiation. We examined whether cartridge extract (CE) from used Xpert TB-positive cartridges was, without downstream DNA extraction or purification, suitable for both genotypic DST (MTBDRplus, MTBDRsl), which may permit patients to rapidly receive a XDR-TB diagnosis from a single specimen, and spoligotyping, which could facilitate routine genotyping. To determine the limit-of-detection and diagnostic accuracy, CEs from dilution series of drug-susceptible and -resistant bacilli were tested (MTBDRplus, MTBDRsl). Xpert TB-positive patient sputa CEs (n = 85) were tested (56 Xpert-rifampicin-susceptible, MTBDRplus and MTBDRsl; 29 Xpert-rifampicin-resistant, MTBDRsl). Spoligotyping was done on CEs from dilution series and patient sputa (n = 10). MTBDRplus had high non-valid result rates. MTBDRsl on CEs from dilutions ≥10 3 CFU/ml (C T  ≤ 24, >"low" Xpert semiquantitation category) was accurate, had low indeterminate rates and, on CE from sputa, highly concordant with MTBDRsl isolate results. CE spoligotyping results from dilutions ≥10 3 CFU/ml and sputa were correct. MTBDRsl and spoligotyping on CE are thus highly feasible. These findings reduce the need for additional specimen collection and culture, for which capacity is limited in high-burden countries, and have implications for diagnostic laboratories and TB molecular epidemiology.

  8. NedWind 25 Blade Testing at NREL for the European Standards Measurement and Testing Program

    Energy Technology Data Exchange (ETDEWEB)

    Larwood, S.; Musial, W.; Freebury, G.; Beattie, A.G.

    2001-04-19

    In the mid-90s the European community initiated the Standards, Measurements, and Testing (SMT) program to harmonize testing and measurement procedures in several industries. Within the program, a project was carried out called the European Wind Turbine Testing Procedure Development. The second part of that project, called Blade Test Methods and Techniques, included the United States and was devised to help blade-testing laboratories harmonize their testing methods. This report provides the results of those tests conducted by the National Renewable Energy Laboratory.

  9. The C-Test: An Integrative Measure of Crystallized Intelligence

    Directory of Open Access Journals (Sweden)

    Purya Baghaei

    2015-05-01

    Full Text Available Crystallized intelligence is a pivotal broad ability factor in the major theories of intelligence including the Cattell-Horn-Carroll (CHC model, the three-stratum model, and the extended Gf-Gc (fluid intelligence-crystallized intelligence model and is usually measured by means of vocabulary tests and other verbal tasks. In this paper the C-Test, a text completion test originally proposed as a test of general proficiency in a foreign language, is introduced as an integrative measure of crystallized intelligence. Based on the existing evidence in the literature, it is argued that the construct underlying the C-Test closely matches the abilities underlying the language component of crystallized intelligence, as defined in the well-established theories of intelligence. It is also suggested that by carefully selecting texts from pertinent knowledge domains, the factual knowledge component of crystallized intelligence could also be measured by the C-Test.

  10. The influence of different measurement structures on NRTA test procedures

    International Nuclear Information System (INIS)

    Beedgen, R.

    1986-01-01

    The development of sequential statistical test procedures in the area of near real time material accountancy (NRTA) mostly assumed a fixed measurement model of a given model facility. In this paper different measurement models (dispersion matrices) for a sequence of balance periods are studied. They are used to compare the detection probabilities of three different sequential test procedures for losses of material. It is shown how different plant models have an influence on the sensitivity of specified tests. Great importance for that analysis have the optimal loss patterns in each measurement situation

  11. Surface moisture measurement system hardware acceptance test procedure

    International Nuclear Information System (INIS)

    Ritter, G.A.

    1996-01-01

    The purpose of this acceptance test procedure is to verify that the mechanical and electrical features of the Surface Moisture Measurement System are operating as designed and that the unit is ready for field service. This procedure will be used in conjunction with a software acceptance test procedure, which addresses testing of software and electrical features not addressed in this document. Hardware testing will be performed at the 306E Facility in the 300 Area and the Fuels and Materials Examination Facility in the 400 Area. These systems were developed primarily in support of Tank Waste Remediation System (TWRS) Safety Programs for moisture measurement in organic and ferrocyanide watch list tanks

  12. High-Accuracy Spherical Near-Field Measurements for Satellite Antenna Testing

    DEFF Research Database (Denmark)

    Breinbjerg, Olav

    2017-01-01

    The spherical near-field antenna measurement technique is unique in combining several distinct advantages and it generally constitutes the most accurate technique for experimental characterization of radiation from antennas. From the outset in 1970, spherical near-field antenna measurements have...... matured into a well-established technique that is widely used for testing antennas for many wireless applications. In particular, for high-accuracy applications, such as remote sensing satellite missions in ESA's Earth Observation Programme with uncertainty requirements at the level of 0.05dB - 0.10d......B, the spherical near-field antenna measurement technique is generally superior. This paper addresses the means to achieving high measurement accuracy; these include the measurement technique per se, its implementation in terms of proper measurement procedures, the use of uncertainty estimates, as well as facility...

  13. Robust, accurate, and non-contacting vibration measurement systems: Summary of comparison measurements of the robust laser interferometer and typical accelerometer systems. Volume 1

    International Nuclear Information System (INIS)

    Goodenow, T.C.; Shipman, R.L.; Holland, H.M.

    1995-06-01

    Epoch Engineering, Incorporated (EEI) has completed a series of vibration measurements comparing their newly-developed Robust Laser Interferometer (RLI) with accelerometer-based instrumentation systems. EEI has successfully demonstrated, on several pieces of commonplace machinery, that non-contact, line-of-sight measurements are practical and yield results equal to or, in some cases, better than customary field implementations of accelerometers. The demonstration included analysis and comparison of such phenomena as nonlinearity, transverse sensitivity, harmonics, and signal-to-noise ratio. Fast Fourier Transformations were performed on the accelerometer and the laser system outputs to provide a comparison basis. The RLI was demonstrated, within the limits of the task, to be a viable, line-of-sight, non-contact alternative to accelerometer systems. Several different kinds of machinery were instrumented and compared, including a small pump, a gear-driven cement mixer, a rotor kit, and two small fans. Known machinery vibration sources were verified and RLI system output file formats were verified to be compatible with commercial computer programs used for vibration monitoring and trend analysis. The RLI was also observed to be less subject to electromagnetic interference (EMI) and more capable at very low frequencies

  14. Robust, accurate, and non-contacting vibration measurement systems: Supplemental appendices presenting comparison measurements of the robust laser interferometer and typical accelerometer systems. Volume 2

    International Nuclear Information System (INIS)

    Goodenow, T.C.; Shipman, R.L.; Holland, H.M.

    1995-06-01

    Epoch Engineering, Incorporated (EEI) has completed a series of vibration measurements comparing their newly-developed Robust Laser Interferometer (RLI) with accelerometer-based instrumentation systems. EEI has successfully demonstrated, on several pieces of commonplace machinery, that non-contact, line-of-sight measurements are practical and yield results equal to or, in some cases, better than customary field implementations of accelerometers. The demonstration included analysis and comparison of such phenomena as nonlinearity, transverse sensitivity, harmonics, and signal-to-noise ratio. Fast Fourier Transformations were performed on the accelerometer and the laser system outputs to provide a comparison basis. The RLI was demonstrated, within the limits o the task, to be a viable, line-of-sight, non-contact alternative to accelerometer systems. Several different kinds of machinery were instrumented and. compared, including a small pump, a gear-driven cement mixer, a rotor kit, and two small fans. Known machinery vibration sources were verified and RLI system output file formats were verified to be compatible with commercial computer programs used for vibration monitoring and trend analysis. The RLI was also observed to be less subject to electromagnetic interference (EMI) and more capable at very low frequencies. This document, Volume 2, provides the appendices to this report

  15. Quality testing as a reserve for rationalization measures

    International Nuclear Information System (INIS)

    Babic, H.G.

    1979-01-01

    The increase in large-scale planning activities and their realization in all fields of quality testing as opposed to the requirements for a reduction of costs emphasizes the necessity of rationaling measures. Especially during the planning phases there are a number of possibilities for solving this problem: the determination of reference dates for production devices based on the preparation of dates with regard to machines and testing, the assignment of the testing frequency in dependence of the quotient from deviations in production and characteristics tolerances, the application of methods of operation planning following different priority rules. Apart from already existing systems for normal and computeraided planning of testing material application by the help of which the most optimal testing material is selected for certain testing jobs systematic representations and programs for the planning of the testing procedure and the testing precision will enrich the joint complex of the organization of testing procedures. (orig./RW) [de

  16. Shear punch and microhardness tests for strength and ductility measurements

    International Nuclear Information System (INIS)

    Lucas, G.E.; Odette, G.R.; Sheckherd, J.W.

    1983-01-01

    In response to the requirements of the fusion reactor materials development program for small-scale mechanical property tests, two techniques have been developed, namely ball microhardness and shear punch tests. The ball microhardness test is based on the repeated measurement at increasing loads of the chordal diameter of an impression made by a spherical penetrator. A correlation has been developed to predict the constitutive relation of the test material from these data. In addition, the indentation pile-up geometry can be analyzed to provide information on the homogeneity of plastic flow in the test material. The shear punch test complements the microhardness test. It is based on blanking a circular disk from a fixed sheet metal specimen. The test is instrumented to provide punch load-displacement data, and these data can be used to determine flow properties of the test material such as yield stress, ultimate tensile strength, work-hardening exponent, and reduction of area

  17. Accurate and absolute diffusion measurements of Rhodamine 6G in low-concentration aqueous solutions by the PGSE-WATERGATE sequence

    Science.gov (United States)

    Majer, G.; Zick, K.

    2015-04-01

    A pulsed field gradient spin-echo nuclear magnetic resonance (NMR) sequence with solvent suppression (PGSE-WATERGATE) was applied to accurately measure the diffusion coefficients of Rhodamine 6G (Rh6G) in low-concentration aqueous solutions. Three samples with Rh6G concentrations of CRh6G = 1, 4.5, and 25 μM were investigated. The precise determination of the diffusion coefficients in this low-concentration range was made possible by using a cryogenically cooled NMR probe and by the effective solvent suppression of the PGSE-WATERGATE sequence. The present results bridge the gap between diffusion data measured by fluorescence correlation spectroscopy in the single molecule limit and diffusivities obtained by pulsed field gradient NMR (PFG-NMR) without solvent suppression at higher concentrations. To further extend the concentration range, the diffusion coefficient of Rh6G was also measured on a sample with CRh6G = 410 μM by PFG-NMR. The overall concentration dependence of the Rh6G diffusion at 25 °C is discussed in terms of dimerization of the Rh6G molecules. The concentration-dependent monomer/dimer proportion is deduced from the diffusion data.

  18. Accurate Region-of-Interest Recovery Improves the Measurement of the Cell Migration Rate in the In Vitro Wound Healing Assay.

    Science.gov (United States)

    Bedoya, Cesar; Cardona, Andrés; Galeano, July; Cortés-Mancera, Fabián; Sandoz, Patrick; Zarzycki, Artur

    2017-12-01

    The wound healing assay is widely used for the quantitative analysis of highly regulated cellular events. In this essay, a wound is voluntarily produced on a confluent cell monolayer, and then the rate of wound reduction (WR) is characterized by processing images of the same regions of interest (ROIs) recorded at different time intervals. In this method, sharp-image ROI recovery is indispensable to compensate for displacements of the cell cultures due either to the exploration of multiple sites of the same culture or to transfers from the microscope stage to a cell incubator. ROI recovery is usually done manually and, despite a low-magnification microscope objective is generally used (10x), repositioning imperfections constitute a major source of errors detrimental to the WR measurement accuracy. We address this ROI recovery issue by using pseudoperiodic patterns fixed onto the cell culture dishes, allowing the easy localization of ROIs and the accurate quantification of positioning errors. The method is applied to a tumor-derived cell line, and the WR rates are measured by means of two different image processing software. Sharp ROI recovery based on the proposed method is found to improve significantly the accuracy of the WR measurement and the positioning under the microscope.

  19. S3 HMBC: Spin-State-Selective HMBC for accurate measurement of homonuclear coupling constants. Application to strychnine yielding thirteen hitherto unreported JHH

    Science.gov (United States)

    Kjaerulff, Louise; Benie, Andrew J.; Hoeck, Casper; Gotfredsen, Charlotte H.; Sørensen, Ole W.

    2016-02-01

    A novel method, Spin-State-Selective (S3) HMBC, for accurate measurement of homonuclear coupling constants is introduced. As characteristic for S3 techniques, S3 HMBC yields independent subspectra corresponding to particular passive spin states and thus allows determination of coupling constants between detected spins and homonuclear coupling partners along with relative signs. In the presented S3 HMBC experiment, spin-state selection occurs via large one-bond coupling constants ensuring high editing accuracy and unequivocal sign determination of the homonuclear long-range relative to the associated one-bond coupling constant. The sensitivity of the new experiment is comparable to that of regular edited HMBC and the accuracy of the J/RDC measurement is as usual for E.COSY and S3-type experiments independent of the size of the homonuclear coupling constant of interest. The merits of the method are demonstrated by an application to strychnine where thirteen JHH coupling constants not previously reported could be measured.

  20. Lithography-free resistance thermometry based technique to accurately measure Seebeck coefficient and electrical conductivity for organic and inorganic thin films

    Science.gov (United States)

    Kumar, Pawan; Repaka, D. V. Maheswar; Hippalgaonkar, Kedar

    2017-12-01

    We have developed a new and accurate technique to measure temperature dependent in-plane Seebeck coefficient and electrical conductivity of organic and inorganic thin films. The measurement device consists of one heater, two thermometers, and a four-probe configuration which is patterned on a substrate of choice using a simple shadow mask. The high resolution in temperature measurements and repeatability of resistance thermometry is leveraged while enabling simple implementation using only a shadow mask for patterning. We calibrate the technique using nickel and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) thin films. The error bar for the Seebeck coefficient is less than 1%, almost 10 times better than complementary techniques for thin films. Moreover, our method enables high-throughput characterization of thermoelectric properties of a variety of different large area inorganic and organic thin films that can be prepared by spin coating, drop casting, evaporation, sputtering, or any other growth technique and hence has potential for wide usage in the thermoelectrics and nanoscale transport community to study thin films.

  1. Accurate and absolute diffusion measurements of Rhodamine 6G in low-concentration aqueous solutions by the PGSE-WATERGATE sequence

    Energy Technology Data Exchange (ETDEWEB)

    Majer, G., E-mail: majer@is.mpg.de [Max Planck Institute for Intelligent Systems, Heisenbergstr. 3, 70569 Stuttgart (Germany); Zick, K. [Bruker BioSpin GmbH, Silberstreifen 4, 76287 Rheinstetten (Germany)

    2015-04-28

    A pulsed field gradient spin-echo nuclear magnetic resonance (NMR) sequence with solvent suppression (PGSE-WATERGATE) was applied to accurately measure the diffusion coefficients of Rhodamine 6G (Rh6G) in low-concentration aqueous solutions. Three samples with Rh6G concentrations of C{sub Rh6G} = 1, 4.5, and 25 μM were investigated. The precise determination of the diffusion coefficients in this low-concentration range was made possible by using a cryogenically cooled NMR probe and by the effective solvent suppression of the PGSE-WATERGATE sequence. The present results bridge the gap between diffusion data measured by fluorescence correlation spectroscopy in the single molecule limit and diffusivities obtained by pulsed field gradient NMR (PFG-NMR) without solvent suppression at higher concentrations. To further extend the concentration range, the diffusion coefficient of Rh6G was also measured on a sample with C{sub Rh6G} = 410 μM by PFG-NMR. The overall concentration dependence of the Rh6G diffusion at 25 °C is discussed in terms of dimerization of the Rh6G molecules. The concentration-dependent monomer/dimer proportion is deduced from the diffusion data.

  2. A new laser reflectance system capable of measuring changing cross-sectional area of soft tissues during tensile testing.

    Science.gov (United States)

    Pokhai, Gabriel G; Oliver, Michele L; Gordon, Karen D

    2009-09-01

    Determination of the biomechanical properties of soft tissues such as tendons and ligaments is dependent on the accurate measurement of their cross-sectional area (CSA). Measurement methods, which involve contact with the specimen, are problematic because soft tissues are easily deformed. Noncontact measurement methods are preferable in this regard, but may experience difficulty in dealing with the complex cross-sectional shapes and glistening surfaces seen in soft tissues. Additionally, existing CSA measurement systems are separated from the materials testing machine, resulting in the inability to measure CSA during testing. Furthermore, CSA measurements are usually made in a different orientation, and with a different preload, prior to testing. To overcome these problems, a noncontact laser reflectance system (LRS) was developed. Designed to fit in an Instron 8872 servohydraulic test machine, the system measures CSA by orbiting a laser transducer in a circular path around a soft tissue specimen held by tissue clamps. CSA measurements can be conducted before and during tensile testing. The system was validated using machined metallic specimens of various shapes and sizes, as well as different sizes of bovine tendons. The metallic specimens could be measured to within 4% accuracy, and the tendons to within an average error of 4.3%. Statistical analyses showed no significant differences between the measurements of the LRS and those of the casting method, an established measurement technique. The LRS was successfully used to measure the changing CSA of bovine tendons during uniaxial tensile testing. The LRS developed in this work represents a simple, quick, and accurate way of reconstructing complex cross-sectional profiles and calculating cross-sectional areas. In addition, the LRS represents the first system capable of automatically measuring changing CSA of soft tissues during tensile testing, facilitating the calculation of more accurate biomechanical properties.

  3. 76 FR 1136 - Electroshock Weapons Test and Measurement Workshop

    Science.gov (United States)

    2011-01-07

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE National Institute of Standards and Technology Electroshock Weapons Test and Measurement Workshop AGENCY: National Institute of Standards and Technology (NIST), United States Department of Commerce. ACTION: Notice...

  4. Instructions for 104-SX liquid level measurement field tests

    International Nuclear Information System (INIS)

    Webb, R.H.

    1994-01-01

    This document provides detailed instructions for field testing a suggested solution of inserting a liner inside the 104-SX failed Liquid Observation Well to gain access for making temporary Liquid Level Measurement until a permanent solution has been provided

  5. Direct tests of measurement uncertainty relations: what it takes.

    Science.gov (United States)

    Busch, Paul; Stevens, Neil

    2015-02-20

    The uncertainty principle being a cornerstone of quantum mechanics, it is surprising that, in nearly 90 years, there have been no direct tests of measurement uncertainty relations. This lacuna was due to the absence of two essential ingredients: appropriate measures of measurement error (and disturbance) and precise formulations of such relations that are universally valid and directly testable. We formulate two distinct forms of direct tests, based on different measures of error. We present a prototype protocol for a direct test of measurement uncertainty relations in terms of value deviation errors (hitherto considered nonfeasible), highlighting the lack of universality of these relations. This shows that the formulation of universal, directly testable measurement uncertainty relations for state-dependent error measures remains an important open problem. Recent experiments that were claimed to constitute invalidations of Heisenberg's error-disturbance relation, are shown to conform with the spirit of Heisenberg's principle if interpreted as direct tests of measurement uncertainty relations for error measures that quantify distances between observables.

  6. Charging and discharging tests for obtaining an accurate dynamic electro-thermal model of high power lithium-ion pack system for hybrid and EV applications

    DEFF Research Database (Denmark)

    Mihet-Popa, Lucian; Camacho, Oscar Mauricio Forero; Nørgård, Per Bromand

    2013-01-01

    . The aim of the tests has been to study the impact of the battery degradation and to find out the dynamic characteristics of the cells including nonlinear open circuit voltage, series resistance and parallel transient circuit at different charge/discharge currents and cell temperature. An equivalent...... circuit model, based on the runtime battery model and the Thevenin circuit model, with parameters obtained from the tests and depending on SOC, current and temperature has been implemented in MATLAB/Simulink and Power Factory. A good alignment between simulations and measurements has been found....

  7. The "Test of Financial Literacy": Development and Measurement Characteristics

    Science.gov (United States)

    Walstad, William B.; Rebeck, Ken

    2017-01-01

    The "Test of Financial Literacy" (TFL) was created to measure the financial knowledge of high school students. Its content is based on the standards and benchmarks stated in the "National Standards for Financial Literacy" (Council for Economic Education 2013). The test development process involved extensive item writing and…

  8. Measuring Intelligence with the Goodenough-Harris Drawing Test.

    Science.gov (United States)

    Scott, Linda Howard

    1981-01-01

    Critically evaluates the literature through 1977 on the Goodenough-Harris Drawing Test. Areas reviewed are administration and standardization of the man and woman scales, test ceiling, sex differences, the Quality scale, reliability, criterion validity, validity with measures of academic achievement, cultural variables, and use with the learning…

  9. Test Station for Measuring Aluminum Tube Geometrical Parameters

    CERN Document Server

    Oansea, D; Gongadze, A L; Gostkin, M I; Dedovich, D V; Evtoukhovitch, P G; Comanescu, B; Kotov, S A; Necsoiu, T; Potrap, I N; Rogalev, E V; Tskhadadze, E G; Chelkov, G A

    2001-01-01

    A test station for quality control of aluminum tube outer diameter and wall thickness is presented. The tested tubes are used for drift detector assembly of ATLAS (LHC, CERN) muon system. The outer diameter and wall thickness of aluminium tubes are measured by means of noncontact optical and ultrasonic methods respectively with the accuracy of 3 {\\mu}m. The testing process is automatic and interacts with the production data base.

  10. Validating Grammaticality Judgment Tests: Evidence from Two New Psycholinguistic Measures

    Science.gov (United States)

    Vafaee, Payman; Suzuki, Yuichi; Kachisnke, Ilina

    2017-01-01

    Several previous factor-analytic studies on the construct validity of grammaticality judgment tests (GJTs) concluded that untimed GJTs measure explicit knowledge (EK) and timed GJTs measure implicit knowledge (IK) (Bowles, 2011; R. Ellis, 2005; R. Ellis & Loewen, 2007). It has also been shown that, irrespective of the time condition chosen,…

  11. Constant time INEPT CT-HSQC (CTi-CT-HSQC) – A new NMR method to measure accurate one-bond J and RDCs with strong 1H–1H couplings in natural abundance

    NARCIS (Netherlands)

    Yu, B.; van Ingen, H.|info:eu-repo/dai/nl/297054651; Freedberg, D.I.

    2013-01-01

    Strong (1)H-(1)H coupling can significantly reduce the accuracy of (1)J(CH) measured from frequency differences in coupled HSQC spectra. Although accurate (1)J(CH) values can be extracted from spectral simulation, it would be more convenient if the same accurate (1)J(CH) values can be obtained

  12. Radiometric instrumentation and measurements guide for photovoltaic performance testing

    Energy Technology Data Exchange (ETDEWEB)

    Myers, D.

    1997-04-01

    The Photovoltaic Module and Systems Performance and Engineering Project at the National Renewable Energy Laboratory performs indoor and outdoor standardization, testing, and monitoring of the performance of a wide range of photovoltaic (PV) energy conversion devices and systems. The PV Radiometric Measurements and Evaluation Team (PVSRME) within that project is responsible for measurement and characterization of natural and artificial optical radiation which stimulates the PV effect. The PV manufacturing and research and development community often approaches project members for technical information and guidance. A great area of interest is radiometric instrumentation, measurement techniques, and data analysis applied to understanding and improving PV cell, module, and system performance. At the Photovoltaic Radiometric Measurements Workshop conducted by the PVSRME team in July 1995, the need to communicate knowledge of solar and optical radiometric measurements and instrumentation, gained as a result of NREL`s long-term experiences, was identified as an activity that would promote improved measurement processes and measurement quality in the PV research and manufacturing community. The purpose of this document is to address the practical and engineering need to understand optical and solar radiometric instrument performance, selection, calibration, installation, and maintenance applicable to indoor and outdoor radiometric measurements for PV calibration, performance, and testing applications. An introductory section addresses radiometric concepts and definitions. Next, concepts essential to spectral radiometric measurements are discussed. Broadband radiometric instrumentation and measurement concepts are then discussed. Each type of measurement serves as an important component of the PV cell, module, and system performance measurement and characterization process.

  13. Surface moisture measurement system hardware acceptance test report

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, G.A., Westinghouse Hanford

    1996-05-28

    This document summarizes the results of the hardware acceptance test for the Surface Moisture Measurement System (SMMS). This test verified that the mechanical and electrical features of the SMMS functioned as designed and that the unit is ready for field service. The bulk of hardware testing was performed at the 306E Facility in the 300 Area and the Fuels and Materials Examination Facility in the 400 Area. The SMMS was developed primarily in support of Tank Waste Remediation System (TWRS) Safety Programs for moisture measurement in organic and ferrocyanide watch list tanks.

  14. INFORMATION-MEASURING TEST SYSTEM OF DIESEL LOCOMOTIVE HYDRAULIC TRANSMISSIONS

    Directory of Open Access Journals (Sweden)

    I. V. Zhukovytskyy

    2015-08-01

    Full Text Available Purpose. The article describes the process of developing the information-measuring test system of diesel locomotives hydraulic transmission, which gives the possibility to obtain baseline data to conduct further studies for the determination of the technical condition of diesel locomotives hydraulic transmission. The improvement of factory technology of post-repair tests of hydraulic transmissions by automating the existing hydraulic transmission test stands according to the specifications of the diesel locomotive repair enterprises was analyzed. It is achieved based on a detailed review of existing foreign information-measuring test systems for hydraulic transmission of diesel locomotives, BelAZ earthmover, aircraft tug, slag car, truck, BelAZ wheel dozer, some brands of tractors, etc. The problem for creation the information-measuring test systems for diesel locomotive hydraulic transmission is being solved, starting in the first place from the possibility of automation of the existing test stand of diesel locomotives hydraulic transmission at Dnipropetrovsk Diesel Locomotive Repair Plant "Promteplovoz". Methodology. In the work the researchers proposed the method to create a microprocessor automated system of diesel locomotives hydraulic transmission stand testing in the locomotive plant conditions. It acts by justifying the selection of the necessary sensors, as well as the application of the necessary hardware and software for information-measuring systems. Findings. Based on the conducted analysis there was grounded the necessity of improvement the plant hydraulic transmission stand testing by creating a microprocessor testing system, supported by the experience of developing such systems abroad. Further research should be aimed to improve the accuracy and frequency of data collection by adopting the more modern and reliable sensors in tandem with the use of filtering software for electromagnetic and other interference. Originality. The

  15. Snow thickness profiling on Antarctic sea ice with GPR—Rapid and accurate measurements with the potential to upscale needles to a haystack

    Science.gov (United States)

    Pfaffhuber, Andreas A.; Lieser, Jan L.; Haas, Christian

    2017-08-01

    Snow thickness on sea ice is a largely undersampled parameter yet of importance for the sea ice mass balance and for satellite-based sea ice thickness estimates and thus our general understanding of global ice volume change. Traditional direct thickness measurements with meter sticks can provide accurate but only spot information, referred to as "needles" due to their pinpoint focus and information, while airborne and satellite remote sensing snow products, referred to as "the haystack," have large uncertainties due to their scale. We demonstrate the remarkable accuracy and applicability of ground-penetrating radar (GPR) snow thickness measurements by comparing them with in situ meter stick data from two field campaigns to Antarctica in late winter/early spring. The efficiency and millimeter-to-centimeter accuracy of GPR enables practitioners to acquire extensive, semiregional data with the potential to upscale needles to the haystack and to potentially calibrate satellite remote sensing products that we confirm to derive roughly 30% of the in situ thickness. We find the radar wave propagation velocity in snow to be rather constant (± 6%), encouraging regional snow thickness surveys. Snow thinner than 10 cm is under the detection limit with the off-the-shelf GPR setup utilized in our study.

  16. Robust Design of Reliability Test Plans Using Degradation Measures.

    Energy Technology Data Exchange (ETDEWEB)

    Lane, Jonathan Wesley; Lane, Jonathan Wesley; Crowder, Stephen V.; Crowder, Stephen V.

    2014-10-01

    With short production development times, there is an increased need to demonstrate product reliability relatively quickly with minimal testing. In such cases there may be few if any observed failures. Thus, it may be difficult to assess reliability using the traditional reliability test plans that measure only time (or cycles) to failure. For many components, degradation measures will contain important information about performance and reliability. These measures can be used to design a minimal test plan, in terms of number of units placed on test and duration of the test, necessary to demonstrate a reliability goal. Generally, the assumption is made that the error associated with a degradation measure follows a known distribution, usually normal, although in practice cases may arise where that assumption is not valid. In this paper, we examine such degradation measures, both simulated and real, and present non-parametric methods to demonstrate reliability and to develop reliability test plans for the future production of components with this form of degradation.

  17. Performance tests for instruments measuring radon activity concentration

    International Nuclear Information System (INIS)

    Beck, T.R.; Buchroeder, H.; Schmidt, V.

    2009-01-01

    Performance tests of electronic instruments measuring the activity concentration of 222 Rn have been carried out with respect to the standard IEC 61577-2. In total, 9 types of instrument operating with ionization chambers or electrostatic collection have been tested for the influence of different climatic and radiological factors on the measurement characteristics. It is concluded that all types of instrument, which are commercially available, are suitable for indoor radon measurements. Because of the dependence on climatic conditions, the outdoor use is partly limited.

  18. Standard test method for measurement of oxidation-reduction potential (ORP) of soil

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This test method covers a procedure and related test equipment for measuring oxidation-reduction potential (ORP) of soil samples removed from the ground. 1.2 The procedure in Section 9 is appropriate for field and laboratory measurements. 1.3 Accurate measurement of oxidation-reduction potential aids in the analysis of soil corrosivity and its impact on buried metallic structure corrosion rates. 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  19. A Measure of Proficiency or Short-Term Memory? Validation of an Elicited Imitation Test for SLA Research

    Science.gov (United States)

    Kim, Youjin; Tracy-Ventura, Nicole; Jung, Yeonjoo

    2016-01-01

    Elicited imitation requires listeners to listen and repeat sentences as accurately as possible. In second language acquisition (SLA) research it has been used for a variety of purposes. Recently, versions of the same elicited imitation test (EIT) have been created in 6 languages with the purpose of measuring second language proficiency (Ortega…

  20. Modal test - Measurement and analysis requirements. [for Viking Orbiter

    Science.gov (United States)

    Wada, B. K.

    1975-01-01

    Data from the Viking Orbiter Modal Test Program are used to illustrate modal test measurement and analysis requirements. The test was performed using a multiple shake dwell technique where data were acquired one channel at a time and recorded on paper tape. Up to ten shakers were used simultaneously, with a complete set of data consisting of 290 strain-gage readings and 125 accelerometer readings. The data analysis provided information sufficient to minimize errors in the data. The list of analyses in order of value is orthogonality, residual mass, frequency sweep, data checks to assure good test data, multilevel trends, global kinetic energy, and global strain energy.

  1. Test-retest reliability for aerodynamic measures of voice.

    Science.gov (United States)

    Awan, Shaheen N; Novaleski, Carolyn K; Yingling, Julie R

    2013-11-01

    The purpose of this study was to investigate the intrasubject reliability of aerodynamic characteristics of the voice within typical/normal speakers across testing sessions using the Phonatory Aerodynamic System (PAS 6600; KayPENTAX, Montvale, NJ). Participants were 60 healthy young adults (30 males and 30 females) between the ages 18 and 31 years with perceptually typical voice. Participants were tested using the PAS 6600 (Phonatory Aerodynamic System) on two separate days with approximately 1 week between each session at approximately the same time of day. Four PAS protocols were conducted (vital capacity, maximum sustained phonation, comfortable sustained phonation, and voicing efficiency) and measures of expiratory volume, maximum phonation time, mean expiratory airflow (during vowel production) and target airflow (obtained via syllable repetition), peak air pressure, aerodynamic power, aerodynamic resistance, and aerodynamic efficiency were obtained during each testing session. Associated acoustic measures of vocal intensity and frequency were also collected. All phonations were elicited at comfortable pitch and loudness. All aerodynamic and associated variables evaluated in this study showed useable test-retest reliability (ie, intraclass correlation coefficients [ICCs] ≥ 0.60). A high degree of mean test-retest reliability was found across all subjects for aerodynamic and associated acoustic measurements of vital capacity, maximum sustained phonation, glottal resistance, and vocal intensity (all with ICCs > 0.75). Although strong ICCs were observed for measures of glottal power and mean expiratory airflow in males, weaker overall results for these measures (ICC range: 0.60-0.67) were observed in females subjects and sizable coefficients of variation were observed for measures of power, resistance, and efficiency in both men and women. Differences in degree of reliability from measure to measure were revealed in greater detail using methods such as ICCs and

  2. Numerical Modelling and Measurement in a Test Secondary Settling Tank

    DEFF Research Database (Denmark)

    Dahl, C.; Larsen, Torben; Petersen, O.

    1994-01-01

    sludge. Phenomena as free and hindered settling and the Bingham plastic characteristic of activated sludge suspensions are included in the numerical model. Further characterisation and test tank experiments are described. The characterisation experiments were designed to measure calibration parameters...... and for comparing measured and calculated result. The numerical model could, fairly accuratly, predict the measured results and both the measured and the calculated results showed a flow field pattern identical to flow fields in full-scale secondary setling tanks. A specific calibration of the Bingham plastic...

  3. Measured data from the Avery Island Site C heater test

    International Nuclear Information System (INIS)

    Waldman, H.; Stickney, R.G.

    1984-11-01

    Over the past six years, a comprehensive field testing program was conducted in the Avery Island salt mine. Three single canister heater tests were included in the testing program. Specifically, electric heaters, which simulate canisters of heat-generating nuclear waste, were placed in the floor of the Avery Island salt mine, and measurements were made of the response of the salt to heating. These tests were in operation by June 1978. One of the three heater tests, Site C, operated for a period of 1858 days and was decommissioned during July and August 1983. This data report presents the temperature and displacement data gathered during the operation and decommissioning of the Site C heater test. The purpose of this data report is to transmit the data to the scientific community. Rigorous analysis and interpretation of the data are considered beyond the scope of a data report. 6 references, 21 figures, 1 table

  4. Testing of Tools for Measurement Vibration in Car

    Directory of Open Access Journals (Sweden)

    Martin JURÁNEK

    2009-06-01

    Full Text Available This work is specialized on testing of several sensors for measurement vibration, that be applicable for measurement on vehicles also behind running. These sensors are connected to PC and universal mobile measuring system cRIO (National Instruments with analog I/O module for measurement vibration, that is described in diploma work: [JURÁNEK 2008]. This system has upped mechanical and heat imunity, small proportions and is therefore acceptable also measurement behind ride vehicles. It compose from two head parts. First is measuring part, composite from instruments cRIO. First part is controlled and monitored by PDA there is connected of wireless (second part hereof system. To system cRIO is possible connect sensors by four BNC connector or after small software change is possible add sensor to other analog modul cRIO. Here will be test several different types of accelerometers (USB sensor company Phidgets, MEMS sensor company Freescale, piezoresistiv and Delta Tron accelerometers company Brüel&Kjær. These sensors is attach to stiff board, board is attach to vibrator and excite by proper signal. Testing will realized with reference to using for measurement in cars. Results will be compared with professional signal analyser LabShop pulse from company Brüel&Kjær.

  5. Organic films deposited on Si p-n junctions: Accurate measurements of fluorescence internal efficiency, and application to luminescent antireflection coatings

    Science.gov (United States)

    Garbuzov, D. Z.; Forrest, S. R.; Tsekoun, A. G.; Burrows, P. E.; Bulović, V.; Thompson, M. E.

    1996-10-01

    Ultraviolet (UV) optical pumping followed by fluorescence wavelength downconversion of thin film organic light emitting materials deposited directly on the surface of Si p-n junction diodes is found to be an accurate and rapid means to determine the film internal fluorescence efficiency. By measuring the photoresponse of the Si detectors in the UV, we find that the organic light emitting films of aluminum tris-(8-hydroxyquinoline) (Alq3), N,N'-diphenyl-N,N'-bis-(3-methylphenyl)- 1,1'-biphenyl-4,4'-diamine, and bis-(8-hydroxyquinaldine)-chlorogallium (Gaq2'Cl), have internal fluorescence efficiencies of 0.30±0.05, 0.35±0.03, and 0.36±0.03, respectively. It has also been found that the organic films can be grown to a thickness which optimizes UV light conversion and can, at the same time, serve as antireflection coatings in the visible spectral region, thereby resulting in enhanced Si photodiode sensitivity extending from the UV to the infrared.

  6. Comparison of muscle/lean mass measurement methods: correlation with functional and biochemical testing.

    Science.gov (United States)

    Buehring, B; Siglinsky, E; Krueger, D; Evans, W; Hellerstein, M; Yamada, Y; Binkley, N

    2018-03-01

    DXA-measured lean mass is often used to assess muscle mass but has limitations. Thus, we compared DXA lean mass with two novel methods-bioelectric impedance spectroscopy and creatine (methyl-d3) dilution. The examined methodologies did not measure lean mass similarly and the correlation with muscle biomarkers/function varied. Muscle function tests predict adverse health outcomes better than lean mass measurement. This may reflect limitations of current mass measurement methods. Newer approaches, e.g., bioelectric impedance spectroscopy (BIS) and creatine (methyl-d3) dilution (D3-C), may more accurately assess muscle mass. We hypothesized that BIS and D3-C measured muscle mass would better correlate with function and bone/muscle biomarkers than DXA measured lean mass. Evaluations of muscle/lean mass, function, and serum biomarkers were obtained in older community-dwelling adults. Mass was assessed by DXA, BIS, and orally administered D3-C. Grip strength, timed up and go, and jump power were examined. Potential muscle/bone serum biomarkers were measured. Mass measurements were compared with functional and serum data using regression analyses; differences between techniques were determined by paired t tests. Mean (SD) age of the 112 (89F/23M) participants was 80.6 (6.0) years. The lean/muscle mass assessments were correlated (.57-.88) but differed (p Lean mass measures were unrelated to the serum biomarkers measured. These three methodologies do not similarly measure muscle/lean mass and should not be viewed as being equivalent. Functional tests assessing maximal muscle strength/power (grip strength and jump power) correlated with all mass measures whereas gait speed was not. None of the selected serum measures correlated with mass. Efforts to optimize muscle mass assessment and identify their relationships with health outcomes are needed.

  7. Gas temperature measurements in short duration turbomachinery test facilities

    Science.gov (United States)

    Cattafesta, L. N.; Epstein, A. H.

    1988-07-01

    Thermocouple rakes for use in short-duration turbomachinery test facilities have been developed using very fine thermocouples. Geometry variations were parametrically tested and showed that bare quartz junction supports (76 microns in diameter) yielded superior performance, and were rugged enough to survive considerable impact damage. Using very low cost signal conditioning electronics, temperature accuracies of 0.3 percent were realized yielding turbine efficiency measurements at the 1-percent level. Ongoing work to improve this accuracy is described.

  8. Data Reconciliation and Gross Error Detection: A Filtered Measurement Test

    International Nuclear Information System (INIS)

    Himour, Y.

    2008-01-01

    Measured process data commonly contain inaccuracies because the measurements are obtained using imperfect instruments. As well as random errors one can expect systematic bias caused by miscalibrated instruments or outliers caused by process peaks such as sudden power fluctuations. Data reconciliation is the adjustment of a set of process data based on a model of the process so that the derived estimates conform to natural laws. In this paper, we will explore a predictor-corrector filter based on data reconciliation, and then a modified version of the measurement test is combined with the studied filter to detect probable outliers that can affect process measurements. The strategy presented is tested using dynamic simulation of an inverted pendulum

  9. Determination of soil properties from standard penetration test complemented by torque measurement (SPT-T

    Directory of Open Access Journals (Sweden)

    Anna S. P. Peixoto

    2014-09-01

    Full Text Available The major problem on geotechnical work is to ensure that no settlements occur during the life cycle of the construction. This involves proper design of foundations and their bearing capacity. The Brazilian standard for design and execution of foundations, ABNT (2010 NBR 6122 imposes the utilization of field tests when designing building foundations. The Standard Penetration Test, SPT, ABNT (2001 NBR 6484, is still the most common in-situ test for those purposes. Ranzini (1988 suggested supplementing the conventional SPT with the measurement of the torque (SPT-T required to turn the split spoon after driving, in order to provide a ‘static’ component to a ‘dynamic’ test. The adhesion between the soil and the sampler, obtained by the torque measurement, could be used to calculate the lateral skin friction of piles. This paper describes the SPT-T procedure including both a supplementary equipment and practical aspects. Also it presents an accurate torque measurement, a prediction method to calculate the bearing capacity of piles used in building foundations using the SPT-T test and a comparison between the estimated bearing capacities of building foundations with instrumented load tests in order to validate the method.

  10. An accurate test of calculated positions and lifetimes for Ne{sup 6+}(1s{sup 2}3lnl{sup '}) {sup 1}L states (n=3 and 4) using a high-resolution electron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bordenave-Montesquieu, A. E-mail: abm@irsamc.ups-tlse.fr; Moretto-Capelle, P.; Bordenave-Montesquieu, D

    2003-05-01

    An accurate test of available calculations for the autoionizing doubly excited states belonging to the Be-like 1s{sup 2}3lnl{sup '} Rydberg series of neon (positions and lifetimes) is presented in this short communication. These theoretical data are used to calculate electron line shapes which are compared, through a fitting procedure, with a high-resolution electron spectrum measured in Ne{sup 8+}(1s{sup 2}) + He collisional system, at 80 keV collision energy and 13.1 deg. observation angle. Present tests concern the n=3 and n=4 singlet states. It is found that some of these calculations suffer from large discrepancies with experiment and do not allow a description of the electron spectrum. A quantitative comparison of measured and calculated post-collisional Coulomb interaction-shifted line positions is also given and briefly discussed; for one theoretical data set, the agreement with experiment is found to be generally within {+-}50 meV; in contrast agreement with other data often considerably scatters within {+-}500 meV and sometimes more.

  11. Shear Strength Measurement Benchmarking Tests for K Basin Sludge Simulants

    Energy Technology Data Exchange (ETDEWEB)

    Burns, Carolyn A.; Daniel, Richard C.; Enderlin, Carl W.; Luna, Maria; Schmidt, Andrew J.

    2009-06-10

    Equipment development and demonstration testing for sludge retrieval is being conducted by the K Basin Sludge Treatment Project (STP) at the MASF (Maintenance and Storage Facility) using sludge simulants. In testing performed at the Pacific Northwest National Laboratory (under contract with the CH2M Hill Plateau Remediation Company), the performance of the Geovane instrument was successfully benchmarked against the M5 Haake rheometer using a series of simulants with shear strengths (τ) ranging from about 700 to 22,000 Pa (shaft corrected). Operating steps for obtaining consistent shear strength measurements with the Geovane instrument during the benchmark testing were refined and documented.

  12. Specification test for Markov models with measurement errors.

    Science.gov (United States)

    Kim, Seonjin; Zhao, Zhibiao

    2014-09-01

    Most existing works on specification testing assume that we have direct observations from the model of interest. We study specification testing for Markov models based on contaminated observations. The evolving model dynamics of the unobservable Markov chain is implicitly coded into the conditional distribution of the observed process. To test whether the underlying Markov chain follows a parametric model, we propose measuring the deviation between nonparametric and parametric estimates of conditional regression functions of the observed process. Specifically, we construct a nonparametric simultaneous confidence band for conditional regression functions and check whether the parametric estimate is contained within the band.

  13. Testing accuracy of long-range ultrasonic sensors for olive tree canopy measurements.

    Science.gov (United States)

    Gamarra-Diezma, Juan Luis; Miranda-Fuentes, Antonio; Llorens, Jordi; Cuenca, Andrés; Blanco-Roldán, Gregorio L; Rodríguez-Lizana, Antonio

    2015-01-28

    Ultrasonic sensors are often used to adjust spray volume by allowing the calculation of the crown volume of tree crops. The special conditions of the olive tree require the use of long-range sensors, which are less accurate and faster than the most commonly used sensors. The main objectives of the study were to determine the suitability of the sensor in terms of sound cone determination, angle errors, crosstalk errors and field measurements. Different laboratory tests were performed to check the suitability of a commercial long-range ultrasonic sensor, as were the experimental determination of the sound cone diameter at several distances for several target materials, the determination of the influence of the angle of incidence of the sound wave on the target and distance on the accuracy of measurements for several materials and the determination of the importance of the errors due to interference between sensors for different sensor spacings and distances for two different materials. Furthermore, sensor accuracy was tested under real field conditions. The results show that the studied sensor is appropriate for olive trees because the sound cone is narrower for an olive tree than for the other studied materials, the olive tree canopy does not have a large influence on the sensor accuracy with respect to distance and angle, the interference errors are insignificant for high sensor spacings and the sensor's field distance measurements were deemed sufficiently accurate.

  14. Testing Accuracy of Long-Range Ultrasonic Sensors for Olive Tree Canopy Measurements

    Directory of Open Access Journals (Sweden)

    Juan Luis Gamarra-Diezma

    2015-01-01

    Full Text Available Ultrasonic sensors are often used to adjust spray volume by allowing the calculation of the crown volume of tree crops. The special conditions of the olive tree require the use of long-range sensors, which are less accurate and faster than the most commonly used sensors. The main objectives of the study were to determine the suitability of the sensor in terms of sound cone determination, angle errors, crosstalk errors and field measurements. Different laboratory tests were performed to check the suitability of a commercial long-range ultrasonic sensor, as were the experimental determination of the sound cone diameter at several distances for several target materials, the determination of the influence of the angle of incidence of the sound wave on the target and distance on the accuracy of measurements for several materials and the determination of the importance of the errors due to interference between sensors for different sensor spacings and distances for two different materials. Furthermore, sensor accuracy was tested under real field conditions. The results show that the studied sensor is appropriate for olive trees because the sound cone is narrower for an olive tree than for the other studied materials, the olive tree canopy does not have a large influence on the sensor accuracy with respect to distance and angle, the interference errors are insignificant for high sensor spacings and the sensor’s field distance measurements were deemed sufficiently accurate.

  15. On the Behaviour of Information Measures for Test Selection

    NARCIS (Netherlands)

    Sent, D.; van der Gaag, L.C.; Bellazzi, R; Abu-Hanna, A; Hunter, J

    2007-01-01

    tests that are expected to yield the largest decrease in the uncertainty about a patient’s diagnosis. For capturing diagnostic uncertainty, often an information measure is used. In this paper, we study the Shannon entropy, the Gini index, and the misclassification error for this purpose. We argue

  16. Modernization of laboratories of test of electric measurer

    International Nuclear Information System (INIS)

    Cuervo, Luis Felipe

    1999-01-01

    The paper presents to the companies that possess test laboratories and calibration of electric measurer, an economic alternative for their modernization, using the repontentiation like an economic solution that it liberates resources to be used in other areas that they want it

  17. Measuring Literary Reading Motivation: Questionnaires Design and Pilot Testing

    Science.gov (United States)

    Chrysos, Michail

    2017-01-01

    This study aims to present the design and pilot testing procedures of the two specific self-report questionnaires were used to measure the two key aspects of reading motivation, self-efficacy and intrinsic motivation in the field of literary (narrative) reading, and the partial factors that jointly shape them. These instruments were outlined in…

  18. Data Modeling for Measurements in the Metrology and Testing Fields

    CERN Document Server

    Pavese, Franco

    2009-01-01

    Offers a comprehensive set of modeling methods for data and uncertainty analysis. This work develops methods and computational tools to address general models that arise in practice, allowing for a more valid treatment of calibration and test data and providing an understanding of complex situations in measurement science

  19. Reliability and Validity Testing of the Physical Resilience Measure

    Science.gov (United States)

    Resnick, Barbara; Galik, Elizabeth; Dorsey, Susan; Scheve, Ann; Gutkin, Susan

    2011-01-01

    Objective: The purpose of this study was to test reliability and validity of the Physical Resilience Scale. Methods: A single-group repeated measure design was used and 130 older adults from three different housing sites participated. Participants completed the Physical Resilience Scale, Hardy-Gill Resilience Scale, 14-item Resilience Scale,…

  20. Validation Testing for Automated Solubility Measurement Equipment Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Lachut, J. S. [Washington River Protection Solutions LLC, Richland, WA (United States)

    2016-01-11

    Laboratory tests have been completed to test the validity of automated solubility measurement equipment using sodium nitrate and sodium chloride solutions (see test plan WRPS-1404441, “Validation Testing for Automated Solubility Measurement Equipment”). The sodium nitrate solution results were within 2-3% of the reference values, so the experiment is considered successful using the turbidity meter. The sodium chloride test was done by sight, as the turbidity meter did not work well using sodium chloride. For example, the “clear” turbidity reading was 53 FNU at 80 °C, 107 FNU at 55 °C, and 151 FNU at 20 °C. The sodium chloride did not work because it is granular and large; as the solution was stirred, the granules stayed to the outside of the reactor and just above the stir bar level, having little impact on the turbidity meter readings as the meter was aimed at the center of the solution. Also, the turbidity meter depth has an impact. The salt tends to remain near the stir bar level. If the meter is deeper in the slurry, it will read higher turbidity, and if the meter is raised higher in the slurry, it will read lower turbidity (possibly near zero) because it reads the “clear” part of the slurry. The sodium chloride solution results, as measured by sight rather than by turbidity instrument readings, were within 5-6% of the reference values.

  1. Cross-calibration of the Siemens mMR: easily acquired accurate PET phantom measurements, long-term stability and reproducibility.

    Science.gov (United States)

    Keller, Sune H; Jakoby, Björn; Svalling, Susanne; Kjaer, Andreas; Højgaard, Liselotte; Klausen, Thomas L

    2016-12-01

    We present a quick and easy method to perform quantitatively accurate PET scans of typical water-filled PET plastic shell phantoms on the Siemens Biograph mMR PET/MR system. We perform regular cross-calibrations (Xcal) of our PET systems, including the PET/MR, using a Siemens mCT water phantom. The mMR calibration stability was evaluated over a 3-year period where 54 cross-calibrations were acquired, showing that the mMR on average underestimated the concentration by 16 %, consistently due to the use of MR-based μ-maps. The mMR produced the narrowest calibration ratio range with the lowest standard deviation, implying it is the most stable of the six systems in the study over a 3-year period. MMR ACCURACY WITH PREDEFINED μ-MAPS: With the latest mMR software version, VB20P, it is possible to utilize predefined phantom μ-maps. We evaluated both the system-integrated, predefined μ-map of the long mMR water phantom and our own user-defined CT-based μ-map of the mCT water phantom, which is used for cross-calibration. For seven scans, which were reconstructed with correctly segmented μ-maps, the mMR produced cross-calibration ratios of 1.00-1.02, well within the acceptance range [0.95-1.05], showing high accuracy. The mMR is the most stable PET system in this study, and the mean underestimation is no longer an issue with the easily accessible μ-map, which resulted in correct cross-calibration ratios in all seven tests. We will share the user-defined μ-map of the mCT phantom and the protocol with interested mMR users.

  2. Detection measures in real-life criminal guilty knowledge tests.

    Science.gov (United States)

    Elaad, E; Ginton, A; Jungman, N

    1992-10-01

    The present study provides a first attempt to compare the validity of the respiration line length (RLL) and skin resistance response (SRR) amplitude in real-life criminal guilty knowledge tests (GKTs). GKT records of 40 innocent and 40 guilty Ss, for whom actual truth was established by confession, were assessed for their accuracy. When a predefined decision rule was used and inconclusive decisions were excluded, 97.4% of the innocent Ss and 53.3% of the guilty Ss were correctly classified with the SRR measure. For the RLL measure, the respective results were 97.2% and 53.1%. The combination of both measures improved detection of guilty Ss to 75.8% and decreased detection of innocent Ss to 94.1%. The combined measure seems to be a more useful means of identifying guilty suspects than each physiological measure alone. The results elaborate and extend those obtained in a previous field study conducted by Elaad (1990).

  3. Comparison of Angle of Attack Measurements for Wind Tunnel Testing

    Science.gov (United States)

    Jones, Thomas, W.; Hoppe, John C.

    2001-01-01

    Two optical systems capable of measuring model attitude and deformation were compared to inertial devices employed to acquire wind tunnel model angle of attack measurements during the sting mounted full span 30% geometric scale flexible configuration of the Northrop Grumman Unmanned Combat Air Vehicle (UCAV) installed in the NASA Langley Transonic Dynamics Tunnel (TDT). The overall purpose of the test at TDT was to evaluate smart materials and structures adaptive wing technology. The optical techniques that were compared to inertial devices employed to measure angle of attack for this test were: (1) an Optotrak (registered) system, an optical system consisting of two sensors, each containing a pair of orthogonally oriented linear arrays to compute spatial positions of a set of active markers; and (2) Video Model Deformation (VMD) system, providing a single view of passive targets using a constrained photogrammetric solution whose primary function was to measure wing and control surface deformations. The Optotrak system was installed for this test for the first time at TDT in order to assess the usefulness of the system for future static and dynamic deformation measurements.

  4. Standard test method for conducting potentiodynamic polarization resistance measurements

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1997-01-01

    1.1 This test method covers an experimental procedure for polarization resistance measurements which can be used for the calibration of equipment and verification of experimental technique. The test method can provide reproducible corrosion potentials and potentiodynamic polarization resistance measurements. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  5. Testing Overall and Subpopulation Treatment Effects with Measurement Errors.

    Science.gov (United States)

    Ma, Yanyuan; Yin, Guosheng

    2013-07-01

    There is a growing interest in the discovery of important predictors from many potential biomarkers for therapeutic use. In particular, a biomarker has predictive value for treatment if the treatment is only effective for patients whose biomarker values exceed a certain threshold. However, biomarker expressions are often subject to measurement errors, which may blur the biomarker's predictive capability in patient classification and, as a consequence, may lead to inappropriate treatment decisions. By taking into account the measurement errors, we propose a new testing procedure for the overall and subpopulation treatment effects in the multiple testing framework. The proposed method bypasses the permutation or other resampling procedures that become computationally infeasible in the presence of measurement errors. We conduct simulation studies to examine the performance of the proposed method, and illustrate it with a data example.

  6. Development of accurate dimethyl sulphide primary standard gas mixtures at low nanomole per mole levels in high-pressure aluminium cylinders for ambient measurements

    Science.gov (United States)

    Eon Kim, Mi; Kang, Ji Hwan; Doo Kim, Yong; Lee, Dong Soo; Lee, Sangil

    2018-04-01

    Dimethyl sulphide (DMS) plays an important role in atmospheric chemistry and climate change. Ambient DMS is monitored in a global network and reported at sub-nanomole per mole (nmol/mol) levels. Developing traceable, accurate DMS standards at ambient levels is essential for tracking the long-term trends and understanding the role of DMS in the atmosphere. Gravimetrically prepared gas standards in cylinders are widely used for calibrating instruments. Therefore, a stable primary standard gas mixture (PSM) is required for traceable ambient DMS measurement at remote sites. In this study, to evaluate adsorption loss on the internal surface of the gas cylinder, 6 nmol mol-1 DMS gas mixtures were prepared in three types of aluminium cylinders: a cylinder without a special coating on its internal surface (AL), an Aculife IV  +  III-treated cylinder (AC), and an Experis-treated cylinder (EX). There was little adsorption loss on the EX cylinder, whereas there was substantial adsorption loss on the other two cylinders. The EX cylinder was used to prepare 0.5, 2, 5, and 7 nmol mol-1 DMS PSMs with relative expanded uncertainties of less than 0.4%. The DMS PSMs were analytically verified and consistent within a relative expanded uncertainty of less than 1.2%. The long-term stability of the 7 nmol mol-1 DMS PSM was assessed by tracking the ratio of the DMS to the internal standard, benzene. The results showed that the DMS was stable for about seven months and it was projected to be stable for more than 60 months within a relative expanded uncertainty of 3%.

  7. Cosmological constraints from the CFHTLenS shear measurements using a new, accurate, and flexible way of predicting non-linear mass clustering

    Science.gov (United States)

    Angulo, Raul E.; Hilbert, Stefan

    2015-03-01

    We explore the cosmological constraints from cosmic shear using a new way of modelling the non-linear matter correlation functions. The new formalism extends the method of Angulo & White, which manipulates outputs of N-body simulations to represent the 3D non-linear mass distribution in different cosmological scenarios. We show that predictions from our approach for shear two-point correlations at 1-300 arcmin separations are accurate at the ˜10 per cent level, even for extreme changes in cosmology. For moderate changes, with target cosmologies similar to that preferred by analyses of recent Planck data, the accuracy is close to ˜5 per cent. We combine this approach with a Monte Carlo Markov chain sampler to explore constraints on a Λ cold dark matter model from the shear correlation functions measured in the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS). We obtain constraints on the parameter combination σ8(Ωm/0.27)0.6 = 0.801 ± 0.028. Combined with results from cosmic microwave background data, we obtain marginalized constraints on σ8 = 0.81 ± 0.01 and Ωm = 0.29 ± 0.01. These results are statistically compatible with previous analyses, which supports the validity of our approach. We discuss the advantages of our method and the potential it offers, including a path to model in detail (i) the effects of baryons, (ii) high-order shear correlation functions, and (iii) galaxy-galaxy lensing, among others, in future high-precision cosmological analyses.

  8. Failing Tests: Commentary on "Adapting Educational Measurement to the Demands of Test-Based Accountability"

    Science.gov (United States)

    Thissen, David

    2015-01-01

    In "Adapting Educational Measurement to the Demands of Test-Based Accountability" Koretz takes the time-honored engineering approach to educational measurement, identifying specific problems with current practice and proposing minimal modifications of the system to alleviate those problems. In response to that article, David Thissen…

  9. In Situ Measurements of the NO2/NO Ratio for Testing Atmospheric Photochemical Models

    Science.gov (United States)

    Jaegle, L.; Webster, C. R.; May, R. D.; Fahey, D. W.; Woodbridge, E. L.; Keim, E. R.; Gao, R. S.; Proffitt, M. H.; Stimpfle, R. M.; Salawitch, R. J.

    1994-01-01

    Simultaneous in situ measurements of NO2, NO, O3, ClO, pressure and temperature have been made for the first time, presenting a unique opportunity to test our current understanding of the photochemistry of the lower stratosphere. Data were collected from several flights of the ER-2 aircraft at mid-latitudes in May 1993 during NASA's Stratospheric Photochemistry, Aerosols and Dynamics Expedition (SPADE). The daytime ratio of NO2/NO remains fairly constant at 19 km with a typical value of 0.68 and standard deviation of +/- 0.17. The ratio observations are compared with simple steady-state calculations based on laboratory-measured reaction rates and modeled NO2 photolysis rates. At each measurement point the daytime NO2/NO with its measurement uncertainty overlap the results of steady-state calculations and associated uncertainty. However, over all the ER-2 flights examined, the model systematically overestimates the ratio by 40% on average. Possible sources of error are examined in both model and measurements. It is shown that more accurate laboratory determinations of the NO + O3 reaction rate and of the NO2 cross-sections in the 200-220 K temperature range characteristic of the lower stratosphere would allow for a more robust test of our knowledge of NO(x) photochemistry by reducing significant sources of uncertainties in the interpretation of stratospheric measurements. The present measurements are compared with earlier observations of the ratio at higher altitudes.

  10. Lifetime Measurements of $ \\pi ^+ \\pi ^- $ and $\\pi^{+-} K^{-+}$ Atoms to Test Low-Energy QCD Predictions

    CERN Multimedia

    Iliescu, M A; Ponta, T C; Dumitriu, D E; Afanasyev, L; Zhabitskiy, M; Rykalin, V; Hons, Z; Schacher, J; Yazkov, V; Gerndt, J; Detraz, C C; Guaraldo, C; Dreossi, D; Smolik, J; Gorchakov, O; Nikitin, M; Dudarev, A; Kluson, J; Hansroul, M; Okada, K; Constantinescu, S; Kruglov, V; Komarov, V; Takeutchi, F; Tarta, P D; Kuptsov, A; Nemenov, L; Karpukhin, V; Shliapnikov, P; Brekhovskikh, V; Saborido silva, J J; Drijard, D; Rappazzo, G F; Pentia, M C; Gugiu, M M; Kruglova, L; Pustylnik, Z; Trojek, T; Duma, M; Ciocarlan, C; Kulikov, A; Ol'shevskiy, V; Ryazantsev, A; Chiba, M; Anania, A; Tarasov, A; Gritsay, K; Lapchine, V; Cechak, T; Vrba, T; Lopez aguera, A

    2002-01-01

    %PS212 \\\\ \\\\ The proposed experiment aims to measure the lifetime of $ \\pi ^+ \\pi ^- $ atoms in the ground state with 10\\% precision, using the 24~GeV/c proton beam of the CERN Proton Synchrotron. As the value of the above lifetime of order 10$ ^- ^{1} ^{5} $s is dictated by a strong interaction at low energy, the precise measurement of this quantity enables to determine a combination of S-wave pion scattering lengths to 5\\%. Pion scattering lengths have been calculated in the framework of chiral perturbation theory and values predicted at the same level of accuracy have, up to now, never been confronted with accurate experimental data. Such a measurement would submit the understanding of chiral symmetry breaking of QCD to a crucial test.

  11. Testing limits to airflow perturbation device (APD measurements

    Directory of Open Access Journals (Sweden)

    Jamshidi Shaya

    2008-10-01

    Full Text Available Abstract Background The Airflow Perturbation Device (APD is a lightweight, portable device that can be used to measure total respiratory resistance as well as inhalation and exhalation resistances. There is a need to determine limits to the accuracy of APD measurements for different conditions likely to occur: leaks around the mouthpiece, use of an oronasal mask, and the addition of resistance in the respiratory system. Also, there is a need for resistance measurements in patients who are ventilated. Method Ten subjects between the ages of 18 and 35 were tested for each station in the experiment. The first station involved testing the effects of leaks of known sizes on APD measurements. The second station tested the use of an oronasal mask used in conjunction with the APD during nose and mouth breathing. The third station tested the effects of two different resistances added in series with the APD mouthpiece. The fourth station tested the usage of a flexible ventilator tube in conjunction with the APD. Results All leaks reduced APD resistance measurement values. Leaks represented by two 3.2 mm diameter tubes reduced measured resistance by about 10% (4.2 cmH2O·sec/L for control and 3.9 cm H2O·sec/L for the leak. This was not statistically significant. Larger leaks given by 4.8 and 6.4 mm tubes reduced measurements significantly (3.4 and 3.0 cm cmH2O·sec/L, respectively. Mouth resistance measured with a cardboard mouthpiece gave an APD measurement of 4.2 cm H2O·sec/L and mouth resistance measured with an oronasal mask was 4.5 cm H2O·sec/L; the two were not significantly different. Nose resistance measured with the oronasal mask was 7.6 cm H2O·sec/L. Adding airflow resistances of 1.12 and 2.10 cm H2O·sec/L to the breathing circuit between the mouth and APD yielded respiratory resistance values higher than the control by 0.7 and 2.0 cm H2O·sec/L. Although breathing through a 52 cm length of flexible ventilator tubing reduced the APD

  12. Discrete Spectral Local Measurement Method for Testing Solar Concentrators

    Directory of Open Access Journals (Sweden)

    Huifu Zhao

    2012-01-01

    Full Text Available In order to compensate for the inconvenience and instability of outdoor photovoltaic concentration test system which are caused by the weather changes, we design an indoor concentration test system with a large caliber and a high parallelism, and then verify its feasibility and scientificity. Furthermore, we propose a new concentration test method: the discrete spectral local measurement method. A two-stage Fresnel concentration system is selected as the test object. The indoor and the outdoor concentration experiments are compared. The results show that the outdoor concentration efficiency of the two-stage Fresnel concentration system is 85.56%, while the indoor is 85.45%. The two experimental results are so close that we can verify the scientificity and feasibility of the indoor concentration test system. The light divergence angle of the indoor concentration test system is 0.267° which also matches with sunlight divergence angle. The indoor concentration test system with large diameter (145 mm, simple structure, and low cost will have broad applications in solar concentration field.

  13. Standard test method for measurement of fatigue crack growth rates

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2015-01-01

    1.1 This test method covers the determination of fatigue crack growth rates from near-threshold to Kmax controlled instability. Results are expressed in terms of the crack-tip stress-intensity factor range (ΔK), defined by the theory of linear elasticity. 1.2 Several different test procedures are provided, the optimum test procedure being primarily dependent on the magnitude of the fatigue crack growth rate to be measured. 1.3 Materials that can be tested by this test method are not limited by thickness or by strength so long as specimens are of sufficient thickness to preclude buckling and of sufficient planar size to remain predominantly elastic during testing. 1.4 A range of specimen sizes with proportional planar dimensions is provided, but size is variable to be adjusted for yield strength and applied force. Specimen thickness may be varied independent of planar size. 1.5 The details of the various specimens and test configurations are shown in Annex A1-Annex A3. Specimen configurations other than t...

  14. Constructing three emotion knowledge tests from the invariant measurement approach

    Directory of Open Access Journals (Sweden)

    Ana R. Delgado

    2017-09-01

    Full Text Available Background Psychological constructionist models like the Conceptual Act Theory (CAT postulate that complex states such as emotions are composed of basic psychological ingredients that are more clearly respected by the brain than basic emotions. The objective of this study was the construction and initial validation of Emotion Knowledge measures from the CAT frame by means of an invariant measurement approach, the Rasch Model (RM. Psychological distance theory was used to inform item generation. Methods Three EK tests—emotion vocabulary (EV, close emotional situations (CES and far emotional situations (FES—were constructed and tested with the RM in a community sample of 100 females and 100 males (age range: 18–65, both separately and conjointly. Results It was corroborated that data-RM fit was sufficient. Then, the effect of type of test and emotion on Rasch-modelled item difficulty was tested. Significant effects of emotion on EK item difficulty were found, but the only statistically significant difference was that between “happiness” and the remaining emotions; neither type of test, nor interaction effects on EK item difficulty were statistically significant. The testing of gender differences was carried out after corroborating that differential item functioning (DIF would not be a plausible alternative hypothesis for the results. No statistically significant sex-related differences were found out in EV, CES, FES, or total EK. However, the sign of d indicate that female participants were consistently better than male ones, a result that will be of interest for future meta-analyses. Discussion The three EK tests are ready to be used as components of a higher-level measurement process.

  15. Standards for measurements and testing of wind turbine power quality

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, P. [Risoe National Lab., Roskilde (Denmark); Gerdes, G.; Klosse, R.; Santjer, F. [DEWI, Wilhelmshaven (Germany); Robertson, N.; Davy, W. [NEL, Glasgow (United Kingdom); Koulouvari, M.; Morfiadakis, E. [CRES, Pikermi (Greece); Larsson, Aa. [Chalmers Univ. of Technology, Goeteborg (Sweden)

    1999-03-01

    The present paper describes the work done in power quality sub-task of the project `European Wind Turbine Testing Procedure Developments` funded by the EU SMT program. The objective of the power quality sub-task has been to make analyses and new recommendation(s) for the standardisation of measurement and verification of wind turbine power quality. The work has been organised in three major activities. The first activity has been to propose measurement procedures and to verify existing and new measurement procedures. This activity has also involved a comparison of the measurements and data processing of the participating partners. The second activity has been to investigate the influence of terrain, grid properties and wind farm summation on the power quality of wind turbines with constant rotor speed. The third activity has been to investigate the influence of terrain, grid properties and wind farm summation on the power quality of wind turbines with variable rotor speed. (au)

  16. Accurate measurements of vadose zone fluxes using automated equilibrium tension plate lysimeters: A synopsis of results from the Spydia research facility, New Zealand.

    Science.gov (United States)

    Wöhling, Thomas; Barkle, Greg; Stenger, Roland; Moorhead, Brian; Wall, Aaron; Clague, Juliet

    2014-05-01

    Automated equilibrium tension plate lysimeters (AETLs) are arguably the most accurate method to measure unsaturated water and contaminant fluxes below the root zone at the scale of up to 1 m². The AETL technique utilizes a porous sintered stainless-steel plate to provide a comparatively large sampling area with a continuously controlled vacuum that is in "equilibrium" with the surrounding vadose zone matric pressure to ensure measured fluxes represent those under undisturbed conditions. This novel lysimeter technique was used at an intensive research site for investigations of contaminant pathways from the land surface to the groundwater on a sheep and beef farm under pastoral land use in the Tutaeuaua subcatchment, New Zealand. The Spydia research facility was constructed in 2005 and was fully operational between 2006 and 2011. Extending from a central access caisson, 15 separately controlled AETLs with 0.2 m² surface area were installed at five depths between 0.4 m and 5.1 m into the undisturbed volcanic vadose zone materials. The unique setup of the facility ensured minimum interference of the experimental equipment and external factors with the measurements. Over the period of more than five years, a comprehensive data set was collected at each of the 15 AETL locations which comprises of time series of soil water flux, pressure head, volumetric water contents, and soil temperature. The soil water was regularly analysed for EC, pH, dissolved carbon, various nitrogen compounds (including nitrate, ammonia, and organic N), phosphorus, bromide, chloride, sulphate, silica, and a range of other major ions, as well as for various metals. Climate data was measured directly at the site (rainfall) and a climate station at 500m distance. The shallow groundwater was sampled at three different depths directly from the Spydia caisson and at various observation wells surrounding the facility. Two tracer experiments were conducted at the site in 2009 and 2010. In the 2009

  17. Recurrence network measures for hypothesis testing using surrogate data: Application to black hole light curves

    Science.gov (United States)

    Jacob, Rinku; Harikrishnan, K. P.; Misra, R.; Ambika, G.

    2018-01-01

    Recurrence networks and the associated statistical measures have become important tools in the analysis of time series data. In this work, we test how effective the recurrence network measures are in analyzing real world data involving two main types of noise, white noise and colored noise. We use two prominent network measures as discriminating statistic for hypothesis testing using surrogate data for a specific null hypothesis that the data is derived from a linear stochastic process. We show that the characteristic path length is especially efficient as a discriminating measure with the conclusions reasonably accurate even with limited number of data points in the time series. We also highlight an additional advantage of the network approach in identifying the dimensionality of the system underlying the time series through a convergence measure derived from the probability distribution of the local clustering coefficients. As examples of real world data, we use the light curves from a prominent black hole system and show that a combined analysis using three primary network measures can provide vital information regarding the nature of temporal variability of light curves from different spectroscopic classes.

  18. Design and performance of a microwave strain measuring system for materials tests

    International Nuclear Information System (INIS)

    Billeter, T.R.; Blackburn, L.D.

    1975-12-01

    Excellent sensitivity and accuracy in the measurement of deformation occurring in materials tests have been achieved with a newly developed microwave frequency sensor and instrumentation system with possible application for strain tests inside nuclear reactors. The strain sensor comprises a microwave cavity resonating in the circular TE 113 and TM 110 modes. Detection of axial strain occurs due to the changes of resonant frequency incurred by cavity length changes. Axial strain sensitivity for the TE 113 mode was 6 x 10 -6 per MHz, whereas radial dimensions of the cavity were related to frequency of the TM 110 mode. Aperture coupling of the cavity to the end wall of K/sub a/ band waveguide provided signal excitation of the two monitored modes. Phase locked frequency stability enabled digital count/display of resonant frequencies to within 70 kHz at 35 GHz. Room temperature tension test results demonstrate a strain measuring sensitivity (+- 1 x 10 -6 ) and accuracy (+ -1 percent of the measured value) equivalent to those of electrical resistance strain gages. The system yields accurate measurements of elastic strains as well as small departures from elastic response and hysteresis behavior during unloading and reloading. Creep test results confirm that measurement sensitivity and accuracy are retained in elevated temperature tests. Strain response on loading, subsequent creep deformation and creep recovery after unloading can all be measured in detail. Stability of microwave sensor calibration after exposure for 22 x 10 6 seconds at temperatures from 728 0 K to 866 0 K is shown to be excellent

  19. Infrared thermography for temperature measurement and non-destructive testing.

    Science.gov (United States)

    Usamentiaga, Rubén; Venegas, Pablo; Guerediaga, Jon; Vega, Laura; Molleda, Julio; Bulnes, Francisco G

    2014-07-10

    The intensity of the infrared radiation emitted by objects is mainly a function of their temperature. In infrared thermography, this feature is used for multiple purposes: as a health indicator in medical applications, as a sign of malfunction in mechanical and electrical maintenance or as an indicator of heat loss in buildings. This paper presents a review of infrared thermography especially focused on two applications: temperature measurement and non-destructive testing, two of the main fields where infrared thermography-based sensors are used. A general introduction to infrared thermography and the common procedures for temperature measurement and non-destructive testing are presented. Furthermore, developments in these fields and recent advances are reviewed.

  20. Infrared Thermography for Temperature Measurement and Non-Destructive Testing

    Science.gov (United States)

    Usamentiaga, Rubèn; Venegas, Pablo; Guerediaga, Jon; Vega, Laura; Molleda, Julio; Bulnes, Francisco G.

    2014-01-01

    The intensity of the infrared radiation emitted by objects is mainly a function of their temperature. In infrared thermography, this feature is used for multiple purposes: as a health indicator in medical applications, as a sign of malfunction in mechanical and electrical maintenance or as an indicator of heat loss in buildings. This paper presents a review of infrared thermography especially focused on two applications: temperature measurement and non-destructive testing, two of the main fields where infrared thermography-based sensors are used. A general introduction to infrared thermography and the common procedures for temperature measurement and non-destructive testing are presented. Furthermore, developments in these fields and recent advances are reviewed. PMID:25014096

  1. Infrared Thermography for Temperature Measurement and Non-Destructive Testing

    Directory of Open Access Journals (Sweden)

    Rubén Usamentiaga

    2014-07-01

    Full Text Available The intensity of the infrared radiation emitted by objects is mainly a function of their temperature. In infrared thermography, this feature is used for multiple purposes: as a health indicator in medical applications, as a sign of malfunction in mechanical and electrical maintenance or as an indicator of heat loss in buildings. This paper presents a review of infrared thermography especially focused on two applications: temperature measurement and non-destructive testing, two of the main fields where infrared thermography-based sensors are used. A general introduction to infrared thermography and the common procedures for temperature measurement and non-destructive testing are presented. Furthermore, developments in these fields and recent advances are reviewed.

  2. Test of Flow Characteristics in Tubular Fuel Assembly I - Establishment of test loop and measurement validation test

    International Nuclear Information System (INIS)

    Park, Jong Hark; Chae, H. T.; Park, C.; Kim, H.

    2005-12-01

    Tubular type fuel has been developed as one of candidates for Advanced HANARO Reactor(AHR). It is necessary to test the flow characteristics such as velocity in each flow channels and pressure drop of tubular type fuel. A hydraulic test-loop to examine the hydraulic characteristics for a tubular type fuel has been designed and constructed. It consists of three parts; a) piping-loop including pump and motor, magnetic flow meter and valves etc, b) test-section part where a simulated tubular type fuel is located, and 3) data acquisition system to get reading signals from sensors or instruments. In this report, considerations during the design and installation of the facility and the selection of data acquisition sensors and instruments are described in detail. Before doing the experiment to measure the flow velocities in flow channels, a preliminary tests have been done for measuring the coolant velocities using pitot-tube and for validating the measurement accuracy as well. Local velocities of the radial direction in circular tubes are measured at regular intervals of 60 degrees by three pitot-tubes. Flow rate inside the circular flow channel can be obtained by integrating the velocity distribution in radial direction. The measured flow rate was compared to that of magnetic flow meter. According to the results, two values had a good agreement, which means that the measurement of coolant velocity by using pitot-tube and the flow rate measured by the magnetic flow meter are reliable. Uncertainty analysis showed that the error of velocity measurement by pitot-tube is less than ±2.21%. The hydraulic test-loop also can be adapted to others such as HANARO 18 and 36 fuel, in-pile system of FTL(Fuel Test Loop), etc

  3. High-throughput image analysis of tumor spheroids: a user-friendly software application to measure the size of spheroids automatically and accurately.

    Science.gov (United States)

    Chen, Wenjin; Wong, Chung; Vosburgh, Evan; Levine, Arnold J; Foran, David J; Xu, Eugenia Y

    2014-07-08

    The increasing number of applications of three-dimensional (3D) tumor spheroids as an in vitro model for drug discovery requires their adaptation to large-scale screening formats in every step of a drug screen, including large-scale image analysis. Currently there is no ready-to-use and free image analysis software to meet this large-scale format. Most existing methods involve manually drawing the length and width of the imaged 3D spheroids, which is a tedious and time-consuming process. This study presents a high-throughput image analysis software application - SpheroidSizer, which measures the major and minor axial length of the imaged 3D tumor spheroids automatically and accurately; calculates the volume of each individual 3D tumor spheroid; then outputs the results in two different forms in spreadsheets for easy manipulations in the subsequent data analysis. The main advantage of this software is its powerful image analysis application that is adapted for large numbers of images. It provides high-throughput computation and quality-control workflow. The estimated time to process 1,000 images is about 15 min on a minimally configured laptop, or around 1 min on a multi-core performance workstation. The graphical user interface (GUI) is also designed for easy quality control, and users can manually override the computer results. The key method used in this software is adapted from the active contour algorithm, also known as Snakes, which is especially suitable for images with uneven illumination and noisy background that often plagues automated imaging processing in high-throughput screens. The complimentary "Manual Initialize" and "Hand Draw" tools provide the flexibility to SpheroidSizer in dealing with various types of spheroids and diverse quality images. This high-throughput image analysis software remarkably reduces labor and speeds up the analysis process. Implementing this software is beneficial for 3D tumor spheroids to become a routine in vitro model

  4. Measuring vulnerability to depression: The Serbian scrambled sentences test - SSST

    Directory of Open Access Journals (Sweden)

    Novović Zdenka

    2014-01-01

    Full Text Available The goal of this study was to establish whether the SSST, a Serbian language scrambled sentences instrument, is a reliable measure of depressive cognitive bias, and whether it captures the suppression tendency as participants exert the additional cognitive effort of memorizing a six-digit number while completing the task. The sample consisted of 1071 students, randomly assigned into two groups. They completed the SSST divided into two blocks of 28 sentences, together with additional cognitive task during either the first or second block, and after that a number of instruments to establish validity of the SSST. The test was shown to be a reliable instrument of depressive cognitive bias. As a measure of suppression the SSST performed partly as expected, only when load was applied in the second half of the test, and fatigue and cognitive effort enhanced suppression. The advantages of the test versus self-description measures were discussed. [Projekat Ministarstva nauke Republike Srbije, br. 179006: Hereditary, environmental, and psychological factors of mental health

  5. Solutions for acceleration measurement in vehicle crash tests

    Science.gov (United States)

    Dima, D. S.; Covaciu, D.

    2017-10-01

    Crash tests are useful for validating computer simulations of road traffic accidents. One of the most important parameters measured is the acceleration. The evolution of acceleration versus time, during a crash test, form a crash pulse. The correctness of the crash pulse determination depends on the data acquisition system used. Recommendations regarding the instrumentation for impact tests are given in standards, which are focused on the use of accelerometers as impact sensors. The goal of this paper is to present the device and software developed by authors for data acquisition and processing. The system includes two accelerometers with different input ranges, a processing unit based on a 32-bit microcontroller and a data logging unit with SD card. Data collected on card, as text files, is processed with a dedicated software running on personal computers. The processing is based on diagrams and includes the digital filters recommended in standards.

  6. Accuracy-based proficiency testing for testosterone measurements with immunoassays and liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Cao, Zhimin Tim; Botelho, Julianne Cook; Rej, Robert; Vesper, Hubert

    2017-06-01

    Accurate testosterone measurements are needed to correctly diagnose and treat patients. Proficiency Testing (PT) programs using modified specimens for testing can be limited because of matrix effects and usage of non-reference measurement procedure (RMP)-defined targets for evaluation. Accuracy-based PT can overcome such limitations; however, there is a lack of information on accuracy-based PT and feasibility of its implementation in evaluation for testosterone measurements. Unaltered, single-donor human serum from 2 male and 2 female adult donors were analyzed for testosterone by 142 NYSDH-certified clinical laboratories using 16 immunoassays and LC-MS/MS methods. Testosterone target values were determined using an RMP. The testosterone target concentrations for the 4 specimens were 15.5, 30.0, 402 and 498ng/dl. The biases ranged from -17.8% to 73.1%, 3.1% to 21.3%, -24.8% to 8.6%, and -22.1% to 6.8% for the 4 specimens, respectively. Using a total error target of ±25.1%, which was calculated using the minimum allowable bias and imprecision, 73% of participating laboratories had ≥3 of the 4 results within these limits. The variability in total testosterone measurements can affect clinical decisions. Accuracy-based PT can significantly contribute to improving testosterone testing by providing reliable data on accuracy in patient care to laboratories, assay manufacturers, and standardization programs. Copyright © 2017. Published by Elsevier B.V.

  7. Standard Test Method for Measuring Binocular Disparity in Transparent Parts

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This test method covers the amount of binocular disparity that is induced by transparent parts such as aircraft windscreens, canopies, HUD combining glasses, visors, or goggles. This test method may be applied to parts of any size, shape, or thickness, individually or in combination, so as to determine the contribution of each transparent part to the overall binocular disparity present in the total “viewing system” being used by a human operator. 1.2 This test method represents one of several techniques that are available for measuring binocular disparity, but is the only technique that yields a quantitative figure of merit that can be related to operator visual performance. 1.3 This test method employs apparatus currently being used in the measurement of optical angular deviation under Method F 801. 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not con...

  8. Accurate measurement in the field of the earth of the general-relativistic precession of the LAGEOS II pericenter and new constraints on non-newtonian gravity.

    Science.gov (United States)

    Lucchesi, David M; Peron, Roberto

    2010-12-03

    The pericenter shift of a binary system represents a suitable observable to test for possible deviations from the newtonian inverse-square law in favor of new weak interactions between macroscopic objects. We analyzed 13 years of tracking data of the LAGEOS satellites with GEODYN II software but with no models for general relativity. From the fit of LAGEOS II pericenter residuals we have been able to obtain a 99.8% agreement with the predictions of Einstein's theory. This result may be considered as a 99.8% measurement in the field of the Earth of the combination of the γ and β parameters of general relativity, and it may be used to constrain possible deviations from the inverse-square law in favor of new weak interactions parametrized by a Yukawa-like potential with strength α and range λ. We obtained |α| ≲ 1 × 10(-11), a huge improvement at a range of about 1 Earth radius.

  9. Implementation of Moderator Circulation Test Temperature Measurement System

    International Nuclear Information System (INIS)

    Lim, Yeong Muk; Hong, Seok Boong; Kim, Min Seok; Choi, Hwa Rim; Kim, Hyung Shin

    2016-01-01

    Moderator Circulation Test(MCT) facility is 1/4 scale facility designed to reproduce the important characteristics of moderator circulation in a CANDU6 calandria under a range of operating conditions. MCT is an equipment with 380 acrylic pipes instead of the heater rods and a preliminary measurement of velocity field using PIV(Particle Image Velocimetry) is performed under the iso-thermal test conditions. The Korea Atomic Energy Research Institute (KAERI) started implementation of MCT Temperature Measurement System (TMS) using multiple infrared sensors. To control multiple infrared sensors, MCT TMS is implemented using National Instruments (NI) LabVIEW programming language. The MCT TMS is implemented to measure sensor data of multiple infrared sensors using the LabVIEW. The 35 sensor pipes of MCT TMS are divided into 2 ports to meet the minimum measurement time of 0.2 seconds. The software of MCT TMS is designed using collection function and processing function. The MCT TMS has the function of monitoring the states of multiple infrared sensors. The GUI screen of MCT TMS is composed of sensor pipe categories for user

  10. Implementation of Moderator Circulation Test Temperature Measurement System

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Yeong Muk; Hong, Seok Boong; Kim, Min Seok; Choi, Hwa Rim [KAERI, Daejeon (Korea, Republic of); Kim, Hyung Shin [Chungnam University, Daejeon (Korea, Republic of)

    2016-05-15

    Moderator Circulation Test(MCT) facility is 1/4 scale facility designed to reproduce the important characteristics of moderator circulation in a CANDU6 calandria under a range of operating conditions. MCT is an equipment with 380 acrylic pipes instead of the heater rods and a preliminary measurement of velocity field using PIV(Particle Image Velocimetry) is performed under the iso-thermal test conditions. The Korea Atomic Energy Research Institute (KAERI) started implementation of MCT Temperature Measurement System (TMS) using multiple infrared sensors. To control multiple infrared sensors, MCT TMS is implemented using National Instruments (NI) LabVIEW programming language. The MCT TMS is implemented to measure sensor data of multiple infrared sensors using the LabVIEW. The 35 sensor pipes of MCT TMS are divided into 2 ports to meet the minimum measurement time of 0.2 seconds. The software of MCT TMS is designed using collection function and processing function. The MCT TMS has the function of monitoring the states of multiple infrared sensors. The GUI screen of MCT TMS is composed of sensor pipe categories for user.

  11. Development and testing of a community flood resilience measurement tool

    Science.gov (United States)

    Keating, Adriana; Campbell, Karen; Szoenyi, Michael; McQuistan, Colin; Nash, David; Burer, Meinrad

    2017-01-01

    Given the increased attention on resilience strengthening in international humanitarian and development work, there is a growing need to invest in its measurement and the overall accountability of resilience strengthening initiatives. The purpose of this article is to present our framework and tool for measuring community-level resilience to flooding and generating empirical evidence and to share our experience in the application of the resilience concept. At the time of writing the tool is being tested in 75 communities across eight countries. Currently 88 potential sources of resilience are measured at the baseline (initial state) and end line (final state) approximately 2 years later. If a flood occurs in the community during the study period, resilience outcome measures are recorded. By comparing pre-flood characteristics to post-flood outcomes, we aim to empirically verify sources of resilience, something which has never been done in this field. There is an urgent need for the continued development of theoretically anchored, empirically verified, and practically applicable disaster resilience measurement frameworks and tools so that the field may (a) deepen understanding of the key components of disaster resilience in order to better target resilience-enhancing initiatives, and (b) enhance our ability to benchmark and measure disaster resilience over time, and (c) compare how resilience changes as a result of different capacities, actions and hazards.

  12. Performance measurements at the fast flux test facility

    International Nuclear Information System (INIS)

    In 1984, Fast Flux Test Facility (FFTF) management recognized the need to develop a measurement system that would quantify the operational performance of the FFTF and the human resources needed to operate it. Driven by declining budgets and the need to safely manage a manpower rampdown at FFTF, an early warning system was developed. Although the initiating event for the early warning system was the need to safely manage a manpower rampdown, many related uses have evolved. The initial desired objective for the FFTF performance measurements was to ensure safety and control of key performance trends. However, the early warning system has provided a more quantitative, supportable basis upon which to make decisions. From this initial narrow focus, efforts in the FFTF plant and supporting organizations are leading to measurement of and, subsequently, improvements in productivity. Pilot projects utilizing statistical process control have started with longer range productivity improvement

  13. The direct measurement of dose enhancement in gamma test facilities

    International Nuclear Information System (INIS)

    Burke, E.A.; Snowden, D.P.; Cappelli, J.R.; Mittleman, S.; Lowe, L.F.

    1989-01-01

    The design and use of a dual cavity ionization chamber for routine measurement of dose enhancement factors in Co-60 gamma test facilities is described. The enhancement factors can be derived directly from the chamber measurements without recourse to reference data that may be difficult to obtain. It is shown, in agreement with earlier work, that the maximum dose enhancement factors can be altered by a factor two as a result of Compton scatter from relatively small amounts of low or high atomic number materials next to the target. The dual chamber permits the ready detection of such effects. This relatively simple device reliably reproduced earlier results obtained by more involved equipment and procedures. Measured enhancement factors are reported for new material combinations not previously examined and compared with recent calculations

  14. Well test flare plume monitoring : results of DIAL measurements in Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Chambers, A. [Alberta Research Council, Edmonton, AB (Canada). Carbon and Energy Management

    2003-07-01

    The DIAL testing system in Alberta is used to track plumes of gaseous waste from sour gas plants and measure emissions of sulfur dioxide, oxides of nitrogen, methane, ethylene, volatile organic compounds, ozone, and benzene. The DIAL system can also determine the efficiency of flare combustion. The remote monitoring and plume tracking system can be used on plumes from tail gas incinerator stacks, sour gas well test flares, and fugitive emissions at sour gas plants. Several graphs and figures were presented to illustrate typical plume profiles, outgoing/returning DIAL signals, and an overview of a typical application. Studies have shown that DIAL can accurately track plumes of sulfur dioxide to at least 2 km and can detect levels that are smaller than 450 {mu}g/m{sup 3}. Some of the limitations for DIAL were also presented. DIAL prefers winds above 7 km/h for fugitives and it did not work in fog. 7 tabs., 25 figs.

  15. AULA virtual reality test as an attention measure: convergent validity with Conners' Continuous Performance Test.

    Science.gov (United States)

    Díaz-Orueta, Unai; Garcia-López, Cristina; Crespo-Eguílaz, Nerea; Sánchez-Carpintero, Rocío; Climent, Gema; Narbona, Juan

    2014-01-01

    The majority of neuropsychological tests used to evaluate attention processes in children lack ecological validity. The AULA Nesplora (AULA) is a continuous performance test, developed in a virtual setting, very similar to a school classroom. The aim of the present study is to analyze the convergent validity between the AULA and the Continuous Performance Test (CPT) of Conners. The AULA and CPT were administered correlatively to 57 children, aged 6-16 years (26.3% female) with average cognitive ability (IQ mean = 100.56, SD = 10.38) who had a diagnosis of attention deficit/hyperactivity disorder (ADHD) according to DSM-IV-TR criteria. Spearman correlations analyses were conducted among the different variables. Significant correlations were observed between both tests in all the analyzed variables (omissions, commissions, reaction time, and variability of reaction time), including for those measures of the AULA based on different sensorial modalities, presentation of distractors, and task paradigms. Hence, convergent validity between both tests was confirmed. Moreover, the AULA showed differences by gender and correlation to Perceptual Reasoning and Working Memory indexes of the WISC-IV, supporting the relevance of IQ measures in the understanding of cognitive performance in ADHD. In addition, the AULA (but not Conners' CPT) was able to differentiate between ADHD children with and without pharmacological treatment for a wide range of measures related to inattention, impulsivity, processing speed, motor activity, and quality of attention focus. Additional measures and advantages of the AULA versus Conners' CPT are discussed.

  16. Multifactorial assessment of measurement errors affecting intraoral quantitative sensory testing reliability.

    Science.gov (United States)

    Moana-Filho, Estephan J; Alonso, Aurelio A; Kapos, Flavia P; Leon-Salazar, Vladimir; Durand, Scott H; Hodges, James S; Nixdorf, Donald R

    2017-07-01

    Measurement error of intraoral quantitative sensory testing (QST) has been assessed using traditional methods for reliability, such as intraclass correlation coefficients (ICCs). Most studies reporting QST reliability focused on assessing one source of measurement error at a time, e.g., inter- or intra-examiner (test-retest) reliabilities and employed two examiners to test inter-examiner reliability. The present study used a complex design with multiple examiners with the aim of assessing the reliability of intraoral QST taking account of multiple sources of error simultaneously. Four examiners of varied experience assessed 12 healthy participants in two visits separated by 48h. Seven QST procedures to determine sensory thresholds were used: cold detection (CDT), warmth detection (WDT), cold pain (CPT), heat pain (HPT), mechanical detection (MDT), mechanical pain (MPT) and pressure pain (PPT). Mixed linear models were used to estimate variance components for reliability assessment; dependability coefficients were used to simulate alternative test scenarios. Most intraoral QST variability arose from differences between participants (8.8-30.5%), differences between visits within participant (4.6-52.8%), and error (13.3-28.3%). For QST procedures other than CDT and MDT, increasing the number of visits with a single examiner performing the procedures would lead to improved dependability (dependability coefficient ranges: single visit, four examiners=0.12-0.54; four visits, single examiner=0.27-0.68). A wide range of reliabilities for QST procedures, as measured by ICCs, was noted for inter- (0.39-0.80) and intra-examiner (0.10-0.62) variation. Reliability of sensory testing can be better assessed by measuring multiple sources of error simultaneously instead of focusing on one source at a time. In experimental settings, large numbers of participants are needed to obtain accurate estimates of treatment effects based on QST measurements. This is different from clinical

  17. A simple, fast and accurate in-situ method to measure the rate of transport of redox species through membranes for lithium batteries

    Science.gov (United States)

    Meddings, Nina; Owen, John R.; Garcia-Araez, Nuria

    2017-10-01

    Lithium ion conducting membranes are important to protect the lithium metal electrode and act as a barrier to crossover species such as polysulphides in Li-S systems, redox mediators in Li-O2 cells or dissolved cathode species or electrolyte oxidation products in high voltage Li-ion batteries. We present an in-situ method for measuring permeability of membranes to crossover redox species. The method employs a 'Swagelok' cell design equipped with a glassy carbon working electrode, in which redox species are placed initially in the counter electrode compartment only. Permeability through the membrane, which separates working and counter electrodes, is determined using a square wave voltammetry technique that allows the concentration of crossover redox species to be evaluated over time with very high precision. We test the method using a model and well-behaved electrochemical system to demonstrate its sensitivity, reproducibility and reliability relative to alternative approaches. This new method offers advantages in terms of small electrolyte volume, and simple, fast, quantitative and in-situ measurement.

  18. ACCURACY TEST OF MICROSOFT KINECT FOR HUMAN MORPHOLOGIC MEASUREMENTS

    Directory of Open Access Journals (Sweden)

    B. Molnár

    2012-08-01

    Full Text Available The Microsoft Kinect sensor, a popular gaming console, is widely used in a large number of applications, including close-range 3D measurements. This low-end device is rather inexpensive compared to similar active imaging systems. The Kinect sensors include an RGB camera, an IR projector, an IR camera and an audio unit. The human morphologic measurements require high accuracy with fast data acquisition rate. To achieve the highest accuracy, the depth sensor and the RGB camera should be calibrated and co-registered to achieve high-quality 3D point cloud as well as optical imagery. Since this is a low-end sensor, developed for different purpose, the accuracy could be critical for 3D measurement-based applications. Therefore, two types of accuracy test are performed: (1 for describing the absolute accuracy, the ranging accuracy of the device in the range of 0.4 to 15 m should be estimated, and (2 the relative accuracy of points depending on the range should be characterized. For the accuracy investigation, a test field was created with two spheres, while the relative accuracy is described by sphere fitting performance and the distance estimation between the sphere center points. Some other factors can be also considered, such as the angle of incidence or the material used in these tests. The non-ambiguity range of the sensor is from 0.3 to 4 m, but, based on our experiences, it can be extended up to 20 m. Obviously, this methodology raises some accuracy issues which make accuracy testing really important.

  19. WTP Waste Feed Qualification: Hydrogen Generation Rate Measurement Apparatus Testing Report

    Energy Technology Data Exchange (ETDEWEB)

    Stone, M. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Newell, J. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Smith, T. E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Pareizs, J. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-0