WorldWideScience

Sample records for accurate absolute measurement

  1. Technological Basis and Scientific Returns for Absolutely Accurate Measurements

    Science.gov (United States)

    Dykema, J. A.; Anderson, J.

    2011-12-01

    The 2006 NRC Decadal Survey fostered a new appreciation for societal objectives as a driving motivation for Earth science. Many high-priority societal objectives are dependent on predictions of weather and climate. These predictions are based on numerical models, which derive from approximate representations of well-founded physics and chemistry on space and timescales appropriate to global and regional prediction. These laws of chemistry and physics in turn have a well-defined quantitative relationship with physical measurement units, provided these measurement units are linked to international measurement standards that are the foundation of contemporary measurement science and standards for engineering and commerce. Without this linkage, measurements have an ambiguous relationship to scientific principles that introduces avoidable uncertainty in analyses, predictions, and improved understanding of the Earth system. Since the improvement of climate and weather prediction is fundamentally dependent on the improvement of the representation of physical processes, measurement systems that reduce the ambiguity between physical truth and observations represent an essential component of a national strategy for understanding and living with the Earth system. This paper examines the technological basis and potential science returns of sensors that make measurements that are quantitatively tied on-orbit to international measurement standards, and thus testable to systematic errors. This measurement strategy provides several distinct benefits. First, because of the quantitative relationship between these international measurement standards and fundamental physical constants, measurements of this type accurately capture the true physical and chemical behavior of the climate system and are not subject to adjustment due to excluded measurement physics or instrumental artifacts. In addition, such measurements can be reproduced by scientists anywhere in the world, at any time

  2. 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.

  3. Accurate measurement of absolute experimental inelastic mean free paths and EELS differential cross-sections

    Energy Technology Data Exchange (ETDEWEB)

    Craven, Alan J.; Bobynko, Joanna; Sala, Bianca; MacLaren, Ian, E-mail: ian.maclaren@glasgow.ac.uk

    2016-11-15

    Methods are described for measuring accurate absolute experimental inelastic mean free paths and differential cross-sections using DualEELS. The methods remove the effects of surface layers and give the results for the bulk materials. The materials used are VC{sub 0.83}, TiC{sub 0.98}, VN{sub 0.97} and TiN{sub 0.88} but the method should be applicable to a wide range of materials. The data was taken at 200 keV using a probe half angle of 29 mrad and a collection angle of 36 mrad. The background can be subtracted from under the ionisation edges, which can then be separated from each other. This is achieved by scaling Hartree-Slater calculated cross-sections to the edges in the atomic regions well above the threshold. The average scaling factors required are 1.00 for the non-metal K-edges and 1.01 for the metal L-edges (with uncertainties of a few percent). If preliminary measurements of the chromatic effects in the post-specimen lenses are correct, both drop to 0.99. The inelastic mean free path for TiC{sub 0.98} was measured as 103.6±0.5 nm compared to the prediction of 126.9 nm based on the widely used Iakoubovskii parameterisation. - Highlights: • We show how to extract absolute cross sections for EELS edges using DualEELS. • The method removes the effects of any surface layers on standards. • We use a needle specimen to determining the mean free path for inelastic scattering. • Constrained background fitting is essential to correct background subtraction. • Absolute cross sections are determined for TiC, TiN, VC and VN.

  4. Accurate radiocarbon age estimation using "early" measurements: a new approach to reconstructing the Paleolithic absolute chronology

    Science.gov (United States)

    Omori, Takayuki; Sano, Katsuhiro; Yoneda, Minoru

    2014-05-01

    This paper presents new correction approaches for "early" radiocarbon ages to reconstruct the Paleolithic absolute chronology. In order to discuss time-space distribution about the replacement of archaic humans, including Neanderthals in Europe, by the modern humans, a massive data, which covers a wide-area, would be needed. Today, some radiocarbon databases focused on the Paleolithic have been published and used for chronological studies. From a viewpoint of current analytical technology, however, the any database have unreliable results that make interpretation of radiocarbon dates difficult. Most of these unreliable ages had been published in the early days of radiocarbon analysis. In recent years, new analytical methods to determine highly-accurate dates have been developed. Ultrafiltration and ABOx-SC methods, as new sample pretreatments for bone and charcoal respectively, have attracted attention because they could remove imperceptible contaminates and derive reliable accurately ages. In order to evaluate the reliability of "early" data, we investigated the differences and variabilities of radiocarbon ages on different pretreatments, and attempted to develop correction functions for the assessment of the reliability. It can be expected that reliability of the corrected age is increased and the age applied to chronological research together with recent ages. Here, we introduce the methodological frameworks and archaeological applications.

  5. Micrometry combined with profile mapping for the absolute measurement of Integrated Column Density (ICD) and for accurate X-ray mass attenuation coefficients using XERT

    Energy Technology Data Exchange (ETDEWEB)

    Islam, M. Tauhidul; Rae, Nicholas A.; Glover, Jack L.; Barnea, Zwi [School of Physics, University of Melbourne, Victoria 3010 (Australia); Chantler, Christopher T., E-mail: chantler@physics.unimelb.edu.a [School of Physics, University of Melbourne, Victoria 3010 (Australia)

    2010-07-21

    Absolute values of the column densities [{rho}t]{sub c} of four gold foils were measured using micrometry combined with the 2D X-ray attenuation profile. The absolute calibration of [{rho}t]{sub c} was made with a reference foil and the [{rho}t]{sub c} of other foils were determined following the thickness transfer method. By this method, we obtain absolute calibration to 0.1% or better which was not possible using only the X-ray map of a single foil over its central region.

  6. New experimental methodology, setup and LabView program for accurate absolute thermoelectric power and electrical resistivity measurements between 25 and 1600 K: application to pure copper, platinum, tungsten, and nickel at very high temperatures.

    Science.gov (United States)

    Abadlia, L; Gasser, F; Khalouk, K; Mayoufi, M; Gasser, J G

    2014-09-01

    In this paper we describe an experimental setup designed to measure simultaneously and very accurately the resistivity and the absolute thermoelectric power, also called absolute thermopower or absolute Seebeck coefficient, of solid and liquid conductors/semiconductors over a wide range of temperatures (room temperature to 1600 K in present work). A careful analysis of the existing experimental data allowed us to extend the absolute thermoelectric power scale of platinum to the range 0-1800 K with two new polynomial expressions. The experimental device is controlled by a LabView program. A detailed description of the accurate dynamic measurement methodology is given in this paper. We measure the absolute thermoelectric power and the electrical resistivity and deduce with a good accuracy the thermal conductivity using the relations between the three electronic transport coefficients, going beyond the classical Wiedemann-Franz law. We use this experimental setup and methodology to give new very accurate results for pure copper, platinum, and nickel especially at very high temperatures. But resistivity and absolute thermopower measurement can be more than an objective in itself. Resistivity characterizes the bulk of a material while absolute thermoelectric power characterizes the material at the point where the electrical contact is established with a couple of metallic elements (forming a thermocouple). In a forthcoming paper we will show that the measurement of resistivity and absolute thermoelectric power characterizes advantageously the (change of) phase, probably as well as DSC (if not better), since the change of phases can be easily followed during several hours/days at constant temperature.

  7. New experimental methodology, setup and LabView program for accurate absolute thermoelectric power and electrical resistivity measurements between 25 and 1600 K: Application to pure copper, platinum, tungsten, and nickel at very high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Abadlia, L.; Mayoufi, M. [Laboratoire de Chimie des Matériaux Inorganiques, Université Badji-Mokhtar Annaba, BP12, 23000 Annaba (Algeria); Gasser, F.; Khalouk, K.; Gasser, J. G., E-mail: jean-georges.gasser@univ-lorraine.fr [Laboratoire de Chimie et Physique - Approche Multi-échelle des Milieux Complexes (LCP-A2MC) Institut de Chimie, Physique et Matériaux, Université de Lorraine, 1 Boulevard Arago - 57078 Metz cedex 3 (France)

    2014-09-15

    In this paper we describe an experimental setup designed to measure simultaneously and very accurately the resistivity and the absolute thermoelectric power, also called absolute thermopower or absolute Seebeck coefficient, of solid and liquid conductors/semiconductors over a wide range of temperatures (room temperature to 1600 K in present work). A careful analysis of the existing experimental data allowed us to extend the absolute thermoelectric power scale of platinum to the range 0-1800 K with two new polynomial expressions. The experimental device is controlled by a LabView program. A detailed description of the accurate dynamic measurement methodology is given in this paper. We measure the absolute thermoelectric power and the electrical resistivity and deduce with a good accuracy the thermal conductivity using the relations between the three electronic transport coefficients, going beyond the classical Wiedemann-Franz law. We use this experimental setup and methodology to give new very accurate results for pure copper, platinum, and nickel especially at very high temperatures. But resistivity and absolute thermopower measurement can be more than an objective in itself. Resistivity characterizes the bulk of a material while absolute thermoelectric power characterizes the material at the point where the electrical contact is established with a couple of metallic elements (forming a thermocouple). In a forthcoming paper we will show that the measurement of resistivity and absolute thermoelectric power characterizes advantageously the (change of) phase, probably as well as DSC (if not better), since the change of phases can be easily followed during several hours/days at constant temperature.

  8. New experimental methodology, setup and LabView program for accurate absolute thermoelectric power and electrical resistivity measurements between 25 and 1600 K: Application to pure copper, platinum, tungsten, and nickel at very high temperatures

    Science.gov (United States)

    Abadlia, L.; Gasser, F.; Khalouk, K.; Mayoufi, M.; Gasser, J. G.

    2014-09-01

    In this paper we describe an experimental setup designed to measure simultaneously and very accurately the resistivity and the absolute thermoelectric power, also called absolute thermopower or absolute Seebeck coefficient, of solid and liquid conductors/semiconductors over a wide range of temperatures (room temperature to 1600 K in present work). A careful analysis of the existing experimental data allowed us to extend the absolute thermoelectric power scale of platinum to the range 0-1800 K with two new polynomial expressions. The experimental device is controlled by a LabView program. A detailed description of the accurate dynamic measurement methodology is given in this paper. We measure the absolute thermoelectric power and the electrical resistivity and deduce with a good accuracy the thermal conductivity using the relations between the three electronic transport coefficients, going beyond the classical Wiedemann-Franz law. We use this experimental setup and methodology to give new very accurate results for pure copper, platinum, and nickel especially at very high temperatures. But resistivity and absolute thermopower measurement can be more than an objective in itself. Resistivity characterizes the bulk of a material while absolute thermoelectric power characterizes the material at the point where the electrical contact is established with a couple of metallic elements (forming a thermocouple). In a forthcoming paper we will show that the measurement of resistivity and absolute thermoelectric power characterizes advantageously the (change of) phase, probably as well as DSC (if not better), since the change of phases can be easily followed during several hours/days at constant temperature.

  9. ABSOLUTE STANDARDS FOR CLIMATE MEASUREMENTS

    Directory of Open Access Journals (Sweden)

    J. Leckey

    2016-10-01

    Full Text Available In a world of changing climate, political uncertainty, and ever-changing budgets, the benefit of measurements traceable to SI standards increases by the day. To truly resolve climate change trends on a decadal time scale, on-orbit measurements need to be referenced to something that is both absolute and unchanging. One such mission is the Climate Absolute Radiance and Refractivity Observatory (CLARREO that will measure a variety of climate variables with an unprecedented accuracy to definitively quantify climate change. In the CLARREO mission, we will utilize phase change cells in which a material is melted to calibrate the temperature of a blackbody that can then be observed by a spectrometer. A material’s melting point is an unchanging physical constant that, through a series of transfers, can ultimately calibrate a spectrometer on an absolute scale. CLARREO consists of two primary instruments: an infrared (IR spectrometer and a reflected solar (RS spectrometer. The mission will contain orbiting radiometers with sufficient accuracy to calibrate other space-based instrumentation and thus transferring the absolute traceability. The status of various mission options will be presented.

  10. Accurate determination of absolute carrier-envelope phase dependence using photo-ionization.

    Science.gov (United States)

    Sayler, A M; Arbeiter, M; Fasold, S; Adolph, D; Möller, M; Hoff, D; Rathje, T; Fetić, B; Milošević, D B; Fennel, T; Paulus, G G

    2015-07-01

    The carrier-envelope phase (CEP) dependence of few-cycle above-threshold ionization (ATI) of Xe is calibrated for use as a reference measurement for determining and controlling the absolute CEP in other interactions. This is achieved by referencing the CEP-dependent ATI measurements of Xe to measurements of atomic H, which are in turn referenced to ab initio calculations for atomic H. This allows for the accurate determination of the absolute CEP dependence of Xe ATI, which enables relatively easy determination of the offset between the relative CEP measured and/or controlled by typical devices and the absolute CEP in the interaction.

  11. Measurements of absolute long distances

    Science.gov (United States)

    Pollinger, Florian; Doloca, Nicolae Radu; Meiners-Hagen, Karl; Wedde, Martin; Abou-Zeid, Ahmed

    2010-08-01

    The production of large components, e. g. in aerospace industries, requires flexible and yet highly precise measurement techniques to determine absolute lengths of up to one hundred metres. Two different approaches are presented in this paper. One is based on a time-of-flight measurement, using a femtosecond frequency comb as an advanced modulator. By the combined phase analysis of lines of different distinct frequencies in the Mega- and Gigahertz frequency range, a measurement distance of one hundred metres with a relative measurement uncertainty of 1x10-7 was achieved in laboratory conditions. In a second approach to long distance measurements, two standard interferometric measurement techniques, i.e. variable synthetic and fixed synthetic wavelength interferometry, were combined. The two interferometry techniques were realised within a single set-up, using two external cavity diode lasers as sources. Experimentally, lengths of up to twenty metres could thus be determined with relative uncertainties below 1x10-6, in good agreement with theoretical analysis. Both techniques, femtosecond fibre laser-based time-of-flight and diode laser-based multiwavelength interferometry, are therefore capable of absolute, guidance-free long distance measurements and have achieved demonstrated relative measurement uncertainties below 1x10-6 for distances over ten metres.

  12. Accurate Measurement of the

    NARCIS (Netherlands)

    Cueto Rojas, H.F.; Maleki Seifar, R.; ten Pierick, A.; Heijnen, J.J.; Wahl, S.A.

    2016-01-01

    Ammonium (NH4+) is the most common N-source for yeast fermentations, and N-limitation is frequently applied to reduce growth and increase product yields. While there is significant molecular knowledge on NH4 + transport and assimilation, there have been few attempts to measure the in vivo

  13. Predicting accurate absolute binding energies in aqueous solution

    DEFF Research Database (Denmark)

    Jensen, Jan Halborg

    2015-01-01

    Recent predictions of absolute binding free energies of host-guest complexes in aqueous solution using electronic structure theory have been encouraging for some systems, while other systems remain problematic. In this paper I summarize some of the many factors that could easily contribute 1-3 kcal......-represented by continuum models. While I focus on binding free energies in aqueous solution the approach also applies (with minor adjustments) to any free energy difference such as conformational or reaction free energy differences or activation free energies in any solvent....... mol(-1) errors at 298 K: three-body dispersion effects, molecular symmetry, anharmonicity, spurious imaginary frequencies, insufficient conformational sampling, wrong or changing ionization states, errors in the solvation free energy of ions, and explicit solvent (and ion) effects that are not well...

  14. ABSOLUTE MEASUREMENT OF THE GANIL BEAM ENERGY

    NARCIS (Netherlands)

    CASANDJIAN, JM; MITTIG, W; BEUNARD, R; GAUDARD, L; LEPINESZILY, A; VILLARI, ACC; AUGER, G; BIANCHI, L; CUNSOLO, A; FOTI, A; LICHTENTHALER, R; PLAGNOL, E; SCHUTZ, Y; SIEMSSEN, RH; WIELECZKO, JP

    1993-01-01

    The energy of the GANIL cyclotron beam was measured on-line during the Pb-208 + Pb-208 elastic scattering experiment ''Search for Color van der Waals Force in the Pb-208 + Pb-208 Mott scattering'' with an absolute precision of 7 x 10(-5) at approximately 1.0 GeV, which represents an improvement of

  15. Accurate measurements in volume data

    NARCIS (Netherlands)

    Oliván Bescós, J.; Bosma, Marco; Smit, Jaap; Mun, S.K.

    2001-01-01

    An algorithm for very accurate visualization of an iso- surface in a 3D medical dataset has been developed in the past few years. This technique is extended in this paper to several kinds of measurements in which exact geometric information of a selected iso-surface is used to derive volume, length,

  16. Absolute method of measuring magnetic susceptibility

    Science.gov (United States)

    Thorpe, A.; Senftle, F.E.

    1959-01-01

    An absolute method of standardization and measurement of the magnetic susceptibility of small samples is presented which can be applied to most techniques based on the Faraday method. The fact that the susceptibility is a function of the area under the curve of sample displacement versus distance of the magnet from the sample, offers a simple method of measuring the susceptibility without recourse to a standard sample. Typical results on a few substances are compared with reported values, and an error of less than 2% can be achieved. ?? 1959 The American Institute of Physics.

  17. Towards absolute laser spectroscopic CO2 isotope ratio measurements

    Science.gov (United States)

    Anyangwe Nwaboh, Javis; Werhahn, Olav; Ebert, Volker

    2017-04-01

    Knowledge of isotope composition of carbon dioxide (CO2) in the atmosphere is necessary to identify sources and sinks of this key greenhouse gas. In the last years, laser spectroscopic techniques such as cavity ring-down spectroscopy (CRDS) and tunable diode laser absorption spectroscopy (TDLAS) have been shown to perform accurate isotope ratio measurements for CO2 and other gases like water vapour (H2O) [1,2]. Typically, isotope ratios are reported in literature referring to reference materials provided by e.g. the International Atomic Energy Agency (IAEA). However, there could be some benefit if field deployable absolute isotope ratio measurement methods were developed to address issues such as exhausted reference material like the Pee Dee Belemnite (PDB) standard. Absolute isotope ratio measurements would be particularly important for situations where reference materials do not even exist. Here, we present CRDS and TDLAS-based absolute isotope ratios (13C/12C ) in atmospheric CO2. We demonstrate the capabilities of the used methods by measuring CO2 isotope ratios in gas standards. We compare our results to values reported for the isotope certified gas standards. Guide to the expression of uncertainty in measurement (GUM) compliant uncertainty budgets on the CRDS and TDLAS absolute isotope ratio measurements are presented, and traceability is addressed. We outline the current impediments in realizing high accuracy absolute isotope ratio measurements using laser spectroscopic methods, propose solutions and the way forward. Acknowledgement Parts of this work have been carried out within the European Metrology Research Programme (EMRP) ENV52 project-HIGHGAS. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union. References [1] B. Kühnreich, S. Wagner, J. C. Habig,·O. Möhler, H. Saathoff, V. Ebert, Appl. Phys. B 119:177-187 (2015). [2] E. Kerstel, L. Gianfrani, Appl. Phys. B 92, 439-449 (2008).

  18. Extracting infrared absolute reflectance from relative reflectance measurements.

    Science.gov (United States)

    Berets, Susan L; Milosevic, Milan

    2012-06-01

    Absolute reflectance measurements are valuable to the optics industry for development of new materials and optical coatings. Yet, absolute reflectance measurements are notoriously difficult to make. In this paper, we investigate the feasibility of extracting the absolute reflectance from a relative reflectance measurement using a reference material with known refractive index.

  19. A highly accurate absolute gravimetric network for Albania, Kosovo and Montenegro

    Science.gov (United States)

    Ullrich, Christian; Ruess, Diethard; Butta, Hubert; Qirko, Kristaq; Pavicevic, Bozidar; Murat, Meha

    2016-04-01

    The objective of this project is to establish a basic gravity network in Albania, Kosovo and Montenegro to enable further investigations in geodetic and geophysical issues. Therefore the first time in history absolute gravity measurements were performed in these countries. The Norwegian mapping authority Kartverket is assisting the national mapping authorities in Kosovo (KCA) (Kosovo Cadastral Agency - Agjencia Kadastrale e Kosovës), Albania (ASIG) (Autoriteti Shtetëror i Informacionit Gjeohapësinor) and in Montenegro (REA) (Real Estate Administration of Montenegro - Uprava za nekretnine Crne Gore) in improving the geodetic frameworks. The gravity measurements are funded by Kartverket. The absolute gravimetric measurements were performed from BEV (Federal Office of Metrology and Surveying) with the absolute gravimeter FG5-242. As a national metrology institute (NMI) the Metrology Service of the BEV maintains the national standards for the realisation of the legal units of measurement and ensures their international equivalence and recognition. Laser and clock of the absolute gravimeter were calibrated before and after the measurements. The absolute gravimetric survey was carried out from September to October 2015. Finally all 8 scheduled stations were successfully measured: there are three stations located in Montenegro, two stations in Kosovo and three stations in Albania. The stations are distributed over the countries to establish a gravity network for each country. The vertical gradients were measured at all 8 stations with the relative gravimeter Scintrex CG5. The high class quality of some absolute gravity stations can be used for gravity monitoring activities in future. The measurement uncertainties of the absolute gravity measurements range around 2.5 micro Gal at all stations (1 microgal = 10-8 m/s2). In Montenegro the large gravity difference of 200 MilliGal between station Zabljak and Podgorica can be even used for calibration of relative gravimeters

  20. Accurate calculation of the absolute free energy of binding for drug molecules.

    Science.gov (United States)

    Aldeghi, Matteo; Heifetz, Alexander; Bodkin, Michael J; Knapp, Stefan; Biggin, Philip C

    2016-01-14

    Accurate prediction of binding affinities has been a central goal of computational chemistry for decades, yet remains elusive. Despite good progress, the required accuracy for use in a drug-discovery context has not been consistently achieved for drug-like molecules. Here, we perform absolute free energy calculations based on a thermodynamic cycle for a set of diverse inhibitors binding to bromodomain-containing protein 4 (BRD4) and demonstrate that a mean absolute error of 0.6 kcal mol-1 can be achieved. We also show a similar level of accuracy (1.0 kcal mol-1) can be achieved in pseudo prospective approach. Bromodomains are epigenetic mark readers that recognize acetylation motifs and regulate gene transcription, and are currently being investigated as therapeutic targets for cancer and inflammation. The unprecedented accuracy offers the exciting prospect that the binding free energy of drug-like compounds can be predicted for pharmacologically relevant targets.

  1. 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.

  2. 38 CFR 4.46 - Accurate measurement.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect to...

  3. New Techniques for Absolute Gravity Measurements.

    Science.gov (United States)

    1983-01-07

    Hammond, J.A. (1978) Bollettino Di Geofisica Teorica ed Applicata Vol. XX. 8. Hammond, J. A., and Iliff, R. L. (1979) The AFGL absolute gravity system...International Gravimetric Bureau, No. L:I-43. 7. Hammond. J.A. (1978) Bollettino Di Geofisica Teorica ed Applicata Vol. XX. 8. Hammond, J.A., and

  4. Measurement of the absolute luminosity with the ALEPH detector

    Science.gov (United States)

    Decamp, D.; Deschizeaux, B.; Goy, C.; Lees, J.-P.; Minard, M.-N.; Alemany, R.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Gaitan, V.; Garrido, Ll.; Mir, Ll. M.; Pacheco, A.; Catanesi, M. G.; Creanza, D.; de Palma, M.; Farilla, A.; Iaselli, G.; Maggi, G.; Maggi, M.; Natali, S.; Nuzzo, S.; Quattromini, M.; Ranieri, A.; Raso, G.; Romano, F.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Gao, Y.; Hu, H.; Huang, D.; Huang, X.; Lin, J.; Lou, J.; Qiao, C.; Ruan, T.; Wang, T.; Xie, Y.; Xu, D.; Xu, R.; Zhang, J.; Zhao, W.; Atwood, W. B.; Bauerdick, L. A. T.; Bird, F.; Blucher, E.; Bonvicini, G.; Bossi, F.; Boudreau, J.; Brown, D.; Burnett, T. H.; Drevermann, H.; Forty, R. W.; Grab, C.; Hagelberg, R.; Haywood, S.; Hilgart, J.; Jost, B.; Kasemann, M.; Knobloch, J.; Lacourt, A.; Lançon, E.; Lehraus, I.; Lohse, T.; Lusiani, A.; Marchioro, A.; Martinez, M.; Mato, P.; Menary, S.; Minten, A.; Miotto, A.; Miquel, R.; Moser, H.-G.; Nash, J.; Palazzi, P.; Ranjard, F.; Redlinger, G.; Roth, A.; Rothberg, J.; Rotscheidt, H.; Saich, M.; Schlatter, D.; Schmelling, M.; Takashima, M.; Tejessy, W.; Wachsmuth, H.; Wasserbaech, S.; Wiedenmann, W.; Witzeling, W.; Wotschack, J.; Ajaltouni, Z.; Badaud, F.; Bardadin-Otwinowska, M.; Bencheikh, A. M.; El Fellous, R.; Falvard, A.; Gay, P.; Guicheney, C.; Harvey, J.; Henrard, P.; Jousset, J.; Michel, B.; Montret, J.-C.; Pallin, D.; Perret, P.; Proriol, J.; Prulhière, F.; Stimpfl, G.; Bertelsen, H.; Hansen, F.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Lindhal, A.; Møllerud, R.; Nilsson, B. S.; Petersen, G.; Efthymiopoulos, I.; Simopoulou, E.; Vayaki, A.; Badier, J.; Blondel, A.; Bonneaud, G.; Bourotte, J.; Braems, F.; Brient, J. C.; Fouque, G.; Gamess, A.; Guirlet, R.; Orteu, S.; Rosowsky, A.; Rougé, A.; Rumpf, M.; Tanaka, R.; Videau, H.; Candlin, D. J.; Veitch, E.; Moneta, L.; Parrini, G.; Corden, M.; Georgiopoulos, C.; Ikeda, M.; Lannutti, J.; Levinthal, D.; Mermikides, M.; Sawyer, L.; Antonelli, A.; Baldini, R.; Bencivenni, G.; Bologna, G.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; D'Ettorre-Piazzoli, B.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Picchi, P.; Zografou, P.; Altoon, B.; Boyle, O.; Halley, A. W.; Ten Have, I.; Hearns, J. L.; Lynch, J. G.; Morton, W. T.; Raine, C.; Scarr, J. M.; Smith, K.; Thompson, A. S.; Turnbull, R. M.; Brandl, B.; Braun, O.; Geiges, R.; Geweniger, C.; Hanke, P.; Hepp, V.; Kluge, E. E.; Maumary, Y.; Putzer, A.; Rensch, B.; Stahl, A.; Tittel, K.; Wunsch, M.; Belk, A. T.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Cattaneo, M.; Dornan, P. J.; Dugeay, S.; Greene, A. M.; Hassard, J. F.; Lieske, N. M.; Patton, S. J.; Payne, D. G.; Phillips, M. J.; Sedgbeer, J. K.; Taylor, G.; Tomalin, I. R.; Wright, A. G.; Girtler, P.; Kuhn, D.; Rudolph, G.; Bowdery, C. K.; Brodbeck, T. J.; Finch, A. J.; Foster, F.; Hughes, G.; Keemer, N. R.; Nuttall, M.; Patel, A.; Rowlingson, B. S.; Sloan, T.; Snow, S. W.; Whelan, E. P.; Barczewski, T.; Kleinknecht, K.; Raab, J.; Renk, B.; Roehn, S.; Sander, H.-G.; Schmidt, H.; Steeg, F.; Walther, S. M.; Wolf, B.; Aubert, J.-J.; Benchouk, C.; Bernard, V.; Bonissent, A.; Carr, J.; Coyle, P.; Drinkard, J.; Etienne, F.; Papalexiou, S.; Payre, P.; Pietrzyk, B.; Qian, Z.; Rousseau, D.; Schwemling, P.; Talby, M.; Becker, H.; Blum, W.; Cattaneo, P.; Cowan, G.; Dehning, B.; Dietl, H.; Dydak, F.; Fernandez-Bosman, M.; Hansl-Kozanecka, T.; Jahn, A.; Kozanecki, W.; Lange, E.; Lauber, J.; Lütjens, G.; Lutz, G.; Männer, W.; Pan, Y.; Richter, R.; Schröder, J.; Schwarz, A. S.; Settles, R.; Stierlin, U.; Denis, R. St.; Thomas, J.; Wolf, G.; Bertin, V.; Boucrot, J.; Callot, O.; Chen, X.; Cordier, A.; Davier, M.; Ganis, G.; Grivaz, J.-F.; Heusse, Ph.; Janot, P.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Veillet, J.-J.; Videau, I.; Zhang, Z.; Zomer, F.; Abbaneo, D.; Amendolia, S. R.; Bagliesi, G.; Batignani, G.; Bosisio, L.; Bottigli, U.; Bradaschia, C.; Carpinelli, M.; Ciocci, M. A.; Dell'Orso, R.; Ferrante, I.; Fidecaro, F.; Foà, L.; Focardi, E.; Forti, F.; Gatto, C.; Giassi, A.; Giorgi, M. A.; Ligabue, F.; Mannelli, E. B.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Sanguinetti, G.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Triggiani, G.; Vannini, C.; Venturi, A.; Verdini, P. G.; Walsh, J.; Carter, J. M.; Green, M. G.; March, P. V.; Medcalf, T.; Quazi, I. S.; Strong, J. A.; Thomas, R. M.; West, L. R.; Wildish, T.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Edwards, M.; Fisher, S. M.; Jones, T. J.; Norton, P. R.; Salmon, D. P.; Thompson, J. C.; Bloch-Devaux, B.; Colas, P.; Klopfenstein, C.; Locci, E.; Loucatos, S.; Monnier, E.; Perez, P.; Perlas, J. A.; Perrier, F.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Vallage, B.; Ashman, J. G.; Booth, C. N.; Buttar, C.; Carney, R.; Cartwright, S.; Combley, F.; Dinsdale, M.; Dogru, M.; Hatfield, F.; Martin, J.; Parker, D.; Reeves, P.; Thompson, L. F.; Bach, E.; Barberio, E.; Brandt, S.; Burkhardt, H.; Gillessen, G.; Grupen, C.; Heitner, G.; Meinhard, H.; Mirabito, L.; Schäfer, U.; Seywerd, H.; Stupperich, C.; Trier, H.; Zeuner, V.; Giannini, G.; Gobbo, B.; Ragusa, F.; Rolandi, L.; Stiegler, U.; Bellantoni, L.; Chen, X.; Cinabro, D.; Conway, J. S.; Cowen, D. F.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; Grahl, J.; Harton, J. L.; Jacobsen, J. E.; Jared, R. C.; Johnson, R. P.; Leclaire, B. W.; Pan, Y. B.; Pater, J. R.; Saadi, Y.; Sharma, V.; Shi, Z. H.; Tang, Y. H.; Walsh, A. M.; Wear, J. A.; Weber, F. V.; Whitney, M. H.; Wu, Sau Lan; Zobernig, G.

    1992-09-01

    We report on the absolute luminosity measurement performed with the ALEPH detector at LEP. The systematic errors of the measurements in 1990 are estimated to be 0.6% (experimental) and 0.3% (theoretical).

  5. Precise absolute gamma-ray wavelength measurements

    Science.gov (United States)

    Kessler, E. G.; Dewey, M. S.; Greene, G. L.; Deslattes, R. D.; Börner, H.

    1991-10-01

    Gamma-ray wavelengths measured with the joint NIST/ILL GAMS4 facility at the High Flux Reactor, Grenoble, France, are discussed. This primary goal of these measurements is gamma-ray wavelengths which are consistent with the optical wavelength scale and the Rydberg constant with an uncertainty no larger than 0.1 ppm for energies up to 5 MeV. The current status of the Bragg angle and crystal lattice spacing measurements on reference energy values, the neutron mass, and the determination of fundamental constants is reviewed. Measurement of structure factors at high energies is also considered.

  6. An absolute calibration system for millimeter-accuracy APOLLO measurements

    Science.gov (United States)

    Adelberger, E. G.; Battat, J. B. R.; Birkmeier, K. J.; Colmenares, N. R.; Davis, R.; Hoyle, C. D.; Huang, L. R.; McMillan, R. J.; Murphy, T. W., Jr.; Schlerman, E.; Skrobol, C.; Stubbs, C. W.; Zach, A.

    2017-12-01

    Lunar laser ranging provides a number of leading experimental tests of gravitation—important in our quest to unify general relativity and the standard model of physics. The apache point observatory lunar laser-ranging operation (APOLLO) has for years achieved median range precision at the  ∼2 mm level. Yet residuals in model-measurement comparisons are an order-of-magnitude larger, raising the question of whether the ranging data are not nearly as accurate as they are precise, or if the models are incomplete or ill-conditioned. This paper describes a new absolute calibration system (ACS) intended both as a tool for exposing and eliminating sources of systematic error, and also as a means to directly calibrate ranging data in situ. The system consists of a high-repetition-rate (80 MHz) laser emitting short (ACS delivers photons to the APOLLO detector at exquisitely well-defined time intervals as a ‘truth’ input against which APOLLO’s timing performance may be judged and corrected. Preliminary analysis indicates no inaccuracies in APOLLO data beyond the  ∼3 mm level, suggesting that historical APOLLO data are of high quality and motivating continued work on model capabilities. The ACS provides the means to deliver APOLLO data both accurate and precise below the 2 mm level.

  7. Absolute density measurements in the middle atmosphere

    Directory of Open Access Journals (Sweden)

    M. Rapp

    Full Text Available In the last ten years a total of 25 sounding rockets employing ionization gauges have been launched at high latitudes ( ~ 70° N to measure total atmospheric density and its small scale fluctuations in an altitude range between 70 and 110 km. While the determination of small scale fluctuations is unambiguous, the total density analysis has been complicated in the past by aerodynamical disturbances leading to densities inside the sensor which are enhanced compared to atmospheric values. Here, we present the results of both Monte Carlo simulations and wind tunnel measurements to quantify this aerodynamical effect. The comparison of the resulting ‘ram-factor’ profiles with empirically determined density ratios of ionization gauge measurements and falling sphere measurements provides excellent agreement. This demonstrates both the need, but also the possibility, to correct aerodynamical influences on measurements from sounding rockets. We have determined a total of 20 density profiles of the mesosphere-lower-thermosphere (MLT region. Grouping these profiles according to season, a listing of mean density profiles is included in the paper. A comparison with density profiles taken from the reference atmospheres CIRA86 and MSIS90 results in differences of up to 40%. This reflects that current reference atmospheres are a significant potential error source for the determination of mixing ratios of, for example, trace gas constituents in the MLT region.

    Key words. Middle atmosphere (composition and chemistry; pressure, density, and temperature; instruments and techniques

  8. Absolute density measurements in the middle atmosphere

    Directory of Open Access Journals (Sweden)

    M. Rapp

    2001-05-01

    Full Text Available In the last ten years a total of 25 sounding rockets employing ionization gauges have been launched at high latitudes ( ~ 70° N to measure total atmospheric density and its small scale fluctuations in an altitude range between 70 and 110 km. While the determination of small scale fluctuations is unambiguous, the total density analysis has been complicated in the past by aerodynamical disturbances leading to densities inside the sensor which are enhanced compared to atmospheric values. Here, we present the results of both Monte Carlo simulations and wind tunnel measurements to quantify this aerodynamical effect. The comparison of the resulting ‘ram-factor’ profiles with empirically determined density ratios of ionization gauge measurements and falling sphere measurements provides excellent agreement. This demonstrates both the need, but also the possibility, to correct aerodynamical influences on measurements from sounding rockets. We have determined a total of 20 density profiles of the mesosphere-lower-thermosphere (MLT region. Grouping these profiles according to season, a listing of mean density profiles is included in the paper. A comparison with density profiles taken from the reference atmospheres CIRA86 and MSIS90 results in differences of up to 40%. This reflects that current reference atmospheres are a significant potential error source for the determination of mixing ratios of, for example, trace gas constituents in the MLT region.Key words. Middle atmosphere (composition and chemistry; pressure, density, and temperature; instruments and techniques

  9. Absolute and Relative Measures of Instructional Sensitivity

    Science.gov (United States)

    Naumann, Alexander; Hartig, Johannes; Hochweber, Jan

    2017-01-01

    Valid inferences on teaching drawn from students' test scores require that tests are sensitive to the instruction students received in class. Accordingly, measures of the test items' instructional sensitivity provide empirical support for validity claims about inferences on instruction. In the present study, we first introduce the concepts of…

  10. Demonstrating an absolute quantum advantage in direct absorption measurement

    National Research Council Canada - National Science Library

    Paul-Antoine Moreau; Javier Sabines-Chesterking; Rebecca Whittaker; Siddarth K Joshi; Patrick M Birchall; Alex McMillan; John G Rarity; Jonathan C F Matthews

    2017-01-01

    ... strategies can be improved. Here, for optical direct absorption measurement, we experimentally demonstrate such an instance of an absolute advantage per photon probe that is exposed to the absorbative sample...

  11. Absolute measurement of the DT primary neutron yield on the National Ignition Facility

    Directory of Open Access Journals (Sweden)

    Leeper R.J.

    2013-11-01

    Full Text Available The measurement of the absolute neutron yield produced in inertial confinement fusion target experiments conducted on the National Ignition Facility (NIF is essential in benchmarking progress towards the goal of achieving ignition on this facility. This paper describes three independent diagnostic techniques that have been developed to make accurate and precise DT neutron yield measurements on the NIF.

  12. Composite phase-shifting algorithm for absolute phase measurement

    Science.gov (United States)

    Zhang, Song

    2012-11-01

    This paper presents a method to recover absolute phase by using only four images: three phase-shifted patterns and one stair pattern. The stair pattern is designed in such a way that the stair changes are perfectly aligned with the phase jumps, and thus absolute phase can be recovered by referring to the stair pattern. Due to system noises and camera and/or projector blurring, a computational framework is also proposed. Because this technique only requires four fringe images for absolute phase recovery, it has the merit of measurement speed. And since the absolute phase is obtained, this technique is suitable for measuring step-height objects. We have developed a digital fringe projection system to verify the performance of the proposed technique.

  13. Absolute photon-flux measurements in the vacuum ultraviolet

    Science.gov (United States)

    Samson, J. A. R.; Haddad, G. N.

    1974-01-01

    Absolute photon-flux measurements in the vacuum ultraviolet have extended to short wavelengths by use of rare-gas ionization chambers. The technique involves the measurement of the ion current as a function of the gas pressure in the ion chamber. The true value of the ion current, and hence the absolute photon flux, is obtained by extrapolating the ion current to zero gas pressure. Examples are given at 162 and 266 A. The short-wavelength limit is determined only by the sensitivity of the current-measuring apparatus and by present knowledge of the photoionization processes that occur in the rate gases.

  14. Urey: to measure the absolute age of Mars

    Science.gov (United States)

    Randolph, J. E.; Plescia, J.; Bar-Cohen, Y.; Bartlett, P.; Bickler, D.; Carlson, R.; Carr, G.; Fong, M.; Gronroos, H.; Guske, P. J.; hide

    2003-01-01

    UREY, a proposed NASA Mars Scout mission will, for the first time, measure the absolute age of an identified igneous rock formation on Mars. By extension to relatively older and younger rock formations dated by remote sensing, these results will enable a new and better understanding of Martian geologic history.

  15. Europe's Other Poverty Measures: Absolute Thresholds Underlying Social Assistance

    Science.gov (United States)

    Bavier, Richard

    2009-01-01

    The first thing many learn about international poverty measurement is that European nations apply a "relative" poverty threshold and that they also do a better job of reducing poverty. Unlike the European model, the "absolute" U.S. poverty threshold does not increase in real value when the nation's standard of living rises,…

  16. Accurate measurement of unsteady state fluid temperature

    Science.gov (United States)

    Jaremkiewicz, Magdalena

    2017-03-01

    In this paper, two accurate methods for determining the transient fluid temperature were presented. Measurements were conducted for boiling water since its temperature is known. At the beginning the thermometers are at the ambient temperature and next they are immediately immersed into saturated water. The measurements were carried out with two thermometers of different construction but with the same housing outer diameter equal to 15 mm. One of them is a K-type industrial thermometer widely available commercially. The temperature indicated by the thermometer was corrected considering the thermometers as the first or second order inertia devices. The new design of a thermometer was proposed and also used to measure the temperature of boiling water. Its characteristic feature is a cylinder-shaped housing with the sheath thermocouple located in its center. The temperature of the fluid was determined based on measurements taken in the axis of the solid cylindrical element (housing) using the inverse space marching method. Measurements of the transient temperature of the air flowing through the wind tunnel using the same thermometers were also carried out. The proposed measurement technique provides more accurate results compared with measurements using industrial thermometers in conjunction with simple temperature correction using the inertial thermometer model of the first or second order. By comparing the results, it was demonstrated that the new thermometer allows obtaining the fluid temperature much faster and with higher accuracy in comparison to the industrial thermometer. Accurate measurements of the fast changing fluid temperature are possible due to the low inertia thermometer and fast space marching method applied for solving the inverse heat conduction problem.

  17. Observer variability of absolute and relative thrombus density measurements in patients with acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Emilie M.M. [Erasmus MC - University Medical Center Rotterdam, Department of Radiology, P.O. Box 2040, Rotterdam (Netherlands); Department of Radiology, AMC, Amsterdam (Netherlands); Yoo, Albert J. [Texas Stroke Institute, Plano, TX (United States); Beenen, Ludo F.; Majoie, Charles B. [Department of Radiology, AMC, Amsterdam (Netherlands); Berkhemer, Olvert A. [Department of Radiology, AMC, Amsterdam (Netherlands); Department of Neurology, Erasmus MC, Rotterdam (Netherlands); Blanken, Mark D. den; Wismans, Carrie [AMC, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Niessen, Wiro J. [Erasmus MC - University Medical Center Rotterdam, Department of Radiology, P.O. Box 2040, Rotterdam (Netherlands); Delft University of Technology, Faculty of Applied Sciences, Delft (Netherlands); Marquering, Henk A. [Department of Radiology, AMC, Amsterdam (Netherlands); AMC, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Collaboration: on behalf of the MR CLEAN investigators

    2016-02-15

    Thrombus density may be a predictor for acute ischemic stroke treatment success. However, only limited data on observer variability for thrombus density measurements exist. This study assesses the variability and bias of four common thrombus density measurement methods by expert and non-expert observers. For 132 consecutive patients with acute ischemic stroke, three experts and two trained observers determined thrombus density by placing three standardized regions of interest (ROIs) in the thrombus and corresponding contralateral arterial segment. Subsequently, absolute and relative thrombus densities were determined using either one or three ROIs. Intraclass correlation coefficient (ICC) was determined, and Bland-Altman analysis was performed to evaluate interobserver and intermethod agreement. Accuracy of the trained observer was evaluated with a reference expert observer using the same statistical analysis. The highest interobserver agreement was obtained for absolute thrombus measurements using three ROIs (ICCs ranging from 0.54 to 0.91). In general, interobserver agreement was lower for relative measurements, and for using one instead of three ROIs. Interobserver agreement of trained non-experts and experts was similar. Accuracy of the trained observer measurements was comparable to the expert interobserver agreement and was better for absolute measurements and with three ROIs. The agreement between the one ROI and three ROI methods was good. Absolute thrombus density measurement has superior interobserver agreement compared to relative density measurement. Interobserver variation is smaller when multiple ROIs are used. Trained non-expert observers can accurately and reproducibly assess absolute thrombus densities using three ROIs. (orig.)

  18. Absolute luminosity measurements with the LHCb detector at the LHC

    CERN Document Server

    Aaij, R; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amhis, Y; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Arrabito, L; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Bailey, D S; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Bediaga, I; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Brisbane, S; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Caicedo Carvajal, J M; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Charles, M; Charpentier, Ph; Chiapolini, N; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Collins, P; Constantin, F; Conti, G; Contu, A; Cook, A; Coombes, M; Corti, G; Cowan, G A; Currie, R; D'Almagne, B; D'Ambrosio, C; David, P; De Bonis, I; De Capua, S; De Cian, M; De Lorenzi, F; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Deissenroth, M; Del Buono, L; Deplano, C; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Eames, C; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; Elsasser, Ch; d'Enterria, D G; Esperante Pereira, D; Estève, L; Falabella, A; Fanchini, E; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garra Tico, J; Garrido, L; Gaspar, C; Gauvin, N; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Gregson, S; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Haefeli, G; Haen, C; Haines, S C; Hampson, T; Hansmann-Menzemer, S; Harji, R; Harnew, N; Harrison, J; Harrison, P F; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hofmann, W; Holubyev, K; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Huston, R S; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; Koblitz, S; Koppenburg, P; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kruzelecki, K; Kucharczyk, M; Kukulak, S; Kumar, R; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Li, L; Li Gioi, L; Lieng, M; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Luisier, J; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Malde, S; Mamunur, R M D; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinez Santos, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Maynard, B; Mazurov, A; McGregor, G; McNulty, R; Mclean, C; Meissner, M; Merk, M; Merkel, J; Messi, R; Miglioranzi, S; Milanes, D A; Minard, M-N; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Musy, M; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nardulli, J; Nasteva, I; Nedos, M; Needham, M; Neufeld, N; Nguyen-Mau, C; Nicol, M; Nies, S; Niess, V; Nikitin, N; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B; Palacios, J; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Paterson, S K; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petrella, A; Petrolini, A; Pie Valls, B; Pietrzyk, B; Pilar, T; Pinci, D; Plackett, R; Playfer, S; Plo Casasus, M; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; du Pree, T; Prisciandaro, J; Pugatch, V; Puig Navarro, A; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Rinnert, K; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodrigues, F; Rodriguez Perez, P; Rogers, G J; Roiser, S; Romanovsky, V; Rouvinet, J; Ruf, T; Ruiz, H; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salzmann, C; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santinelli, R; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schleich, S; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M -H; Schwemmer, R; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shao, B; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skottowe, H P; Skwarnicki, T; Smith, A C; Smith, N A; Sobczak, K; Soler, F J P; Solomin, A; Soomro, F; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Styles, N; Subbiah, V K; Swientek, S; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Topp-Joergensen, S; Tran, M T; Tsaregorodtsev, A; Tuning, N; Ubeda Garcia, M; Ukleja, A; Urquijo, P; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Vervink, K; Viaud, B; Videau, I; Vilasis-Cardona, X; Visniakov, J; Vollhardt, A; Voong, D; Vorobyev, A; Voss, H; Wacker, K; Wandernoth, S; Wang, J; Ward, D R; Webber, A D; Websdale, D; Whitehead, M; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wishahi, J; Witek, M; Witzeling, W; Wotton, S A; Wyllie, K; Xie, Y; Xing, F; Yang, Z; Young, R; Yushchenko, O; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhong, L; Zverev, E; Zvyagin, A

    2012-01-01

    Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In addition to the classic ``van der Meer scan'' method a novel technique has been developed which makes use of direct imaging of the individual beams using beam-gas and beam-beam interactions. This beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. The results of the two methods have comparable precision and are in good agreement. Combining the two methods, an overall precision of 3.5\\% in the absolute lumi...

  19. Sounding rocket measurement of the absolute solar EUV flux utilizing a silicon photodiode

    Science.gov (United States)

    Ogawa, H. S.; Mcmullin, D.; Judge, D. L.; Canfield, L. R.

    1990-01-01

    A newly developed stable and high quantum efficiency silicon photodiode was used to obtain an accurate measurement of the integrated absolute magnitude of the solar extreme UV photon flux in the spectral region between 50 and 800 A. The adjusted daily 10.7-cm solar radio flux and sunspot number were 168.4 and 121, respectively. The unattenuated absolute value of the solar EUV flux at 1 AU in the specified wavelength region was 6.81 x 10 to the 10th photons/sq cm per s. Based on a nominal probable error of 7 percent for National Institute of Standards and Technology detector efficiency measurements in the 50- to 500-A region (5 percent on longer wavelength measurements between 500 and 1216 A), and based on experimental errors associated with the present rocket instrumentation and analysis, a conservative total error estimate of about 14 percent is assigned to the absolute integral solar flux obtained.

  20. Absolute frequency measurements on Mg{sup +} cooling transitions

    Energy Technology Data Exchange (ETDEWEB)

    Batteiger, Valentin; Herrmann, Maximilian; Knuenz, Sebastian; Bernhardt, Birgitta; Udem, Thomas; Haensch, Theodor W. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Zhu, Feng; Schuessler, Hans [Texas A and M University, College Station, Texas (United States)

    2008-07-01

    We present isotopically resolved absolute frequency measurements of both fine structure components of the 3s-3p transition in single, trapped magnesium ions. The transitions are observed in the limit of unresolved sidebands, which would lead to strongly asymmetric line shapes due to cooling and heating if only one laser were swept over the resonance. A novel spectroscopy scheme based on sympathetic cooling and spatially resolved detection allows to observe symmetric lines. The measurements contribute to astronomical searches for drifts of the fine structure constant in quasar absorption spectra and improve the accuracy over previous measurements by two orders of magnitude.

  1. Predicting accurate absolute binding energies in aqueous solution: thermodynamic considerations for electronic structure methods.

    Science.gov (United States)

    Jensen, Jan H

    2015-05-21

    Recent predictions of absolute binding free energies of host-guest complexes in aqueous solution using electronic structure theory have been encouraging for some systems, while other systems remain problematic. In this paper I summarize some of the many factors that could easily contribute 1-3 kcal mol(-1) errors at 298 K: three-body dispersion effects, molecular symmetry, anharmonicity, spurious imaginary frequencies, insufficient conformational sampling, wrong or changing ionization states, errors in the solvation free energy of ions, and explicit solvent (and ion) effects that are not well-represented by continuum models. While I focus on binding free energies in aqueous solution the approach also applies (with minor adjustments) to any free energy difference such as conformational or reaction free energy differences or activation free energies in any solvent.

  2. 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.

  3. Fast and accurate exhaled breath ammonia measurement.

    Science.gov (United States)

    Solga, Steven F; Mudalel, Matthew L; Spacek, Lisa A; Risby, Terence H

    2014-06-11

    This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Together with the quick response time of the monitor, this system is capable of accurately measuring exhaled breath ammonia representative of deep lung systemic levels. Because the system is easy to use and produces real time results, it has enabled experiments to identify factors that influence measurements. For example, mouth rinse and oral pH reproducibly and significantly affect results and therefore must be controlled. Temperature and mode of breathing are other examples. As our understanding of these factors evolves, error is reduced, and clinical studies become more meaningful. This system is very reliable and individual measurements are inexpensive. The sampler is relatively inexpensive and quite portable, but the monitor is neither. This limits options for some clinical studies and provides rational for future innovations.

  4. Alpha absolute power measurement in panic disorder with agoraphobia patients.

    Science.gov (United States)

    de Carvalho, Marcele Regine; Velasques, Bruna Brandão; Freire, Rafael C; Cagy, Maurício; Marques, Juliana Bittencourt; Teixeira, Silmar; Rangé, Bernard P; Piedade, Roberto; Ribeiro, Pedro; Nardi, Antonio Egidio; Akiskal, Hagop Souren

    2013-10-01

    Panic attacks are thought to be a result from a dysfunctional coordination of cortical and brainstem sensory information leading to heightened amygdala activity with subsequent neuroendocrine, autonomic and behavioral activation. Prefrontal areas may be responsible for inhibitory top-down control processes and alpha synchronization seems to reflect this modulation. The objective of this study was to measure frontal absolute alpha-power with qEEG in 24 subjects with panic disorder and agoraphobia (PDA) compared to 21 healthy controls. qEEG data were acquired while participants watched a computer simulation, consisting of moments classified as "high anxiety"(HAM) and "low anxiety" (LAM). qEEG data were also acquired during two rest conditions, before and after the computer simulation display. We observed a higher absolute alpha-power in controls when compared to the PDA patients while watching the computer simulation. The main finding was an interaction between the moment and group factors on frontal cortex. Our findings suggest that the decreased alpha-power in the frontal cortex for the PDA group may reflect a state of high excitability. Our results suggest a possible deficiency in top-down control processes of anxiety reflected by a low absolute alpha-power in the PDA group while watching the computer simulation and they highlight that prefrontal regions and frontal region nearby the temporal area are recruited during the exposure to anxiogenic stimuli. © 2013 Elsevier B.V. All rights reserved.

  5. 242Pu absolute neutron-capture cross section measurement

    Science.gov (United States)

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; Bucher, B.; Chyzh, A.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Jandel, M.; Mosby, S.; O'Donnell, J. M.; Ullmann, J. L.

    2017-09-01

    The absolute neutron-capture cross section of 242Pu was measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. During target fabrication, a small amount of 239Pu was added to the active target so that the absolute scale of the 242Pu(n,γ) cross section could be set according to the known 239Pu(n,f) resonance at En,R = 7.83 eV. The relative scale of the 242Pu(n,γ) cross section covers four orders of magnitude for incident neutron energies from thermal to ≈ 40 keV. The cross section reported in ENDF/B-VII.1 for the 242Pu(n,γ) En,R = 2.68 eV resonance was found to be 2.4% lower than the new absolute 242Pu(n,γ) cross section.

  6. 242Pu absolute neutron-capture cross section measurement

    Directory of Open Access Journals (Sweden)

    Buckner M.Q.

    2017-01-01

    Full Text Available The absolute neutron-capture cross section of 242Pu was measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. During target fabrication, a small amount of 239Pu was added to the active target so that the absolute scale of the 242Pu(n,γ cross section could be set according to the known 239Pu(n,f resonance at En,R = 7.83 eV. The relative scale of the 242Pu(n,γ cross section covers four orders of magnitude for incident neutron energies from thermal to ≈ 40 keV. The cross section reported in ENDF/B-VII.1 for the 242Pu(n,γ En,R = 2.68 eV resonance was found to be 2.4% lower than the new absolute 242Pu(n,γ cross section.

  7. Demonstrating an absolute quantum advantage in direct absorption measurement.

    Science.gov (United States)

    Moreau, Paul-Antoine; Sabines-Chesterking, Javier; Whittaker, Rebecca; Joshi, Siddarth K; Birchall, Patrick M; McMillan, Alex; Rarity, John G; Matthews, Jonathan C F

    2017-07-24

    Engineering apparatus that harness quantum theory promises to offer practical advantages over current technology. A fundamentally more powerful prospect is that such quantum technologies could out-perform any future iteration of their classical counterparts, no matter how well the attributes of those classical strategies can be improved. Here, for optical direct absorption measurement, we experimentally demonstrate such an instance of an absolute advantage per photon probe that is exposed to the absorbative sample. We use correlated intensity measurements of spontaneous parametric downconversion using a commercially available air-cooled CCD, a new estimator for data analysis and a high heralding efficiency photon-pair source. We show this enables improvement in the precision of measurement, per photon probe, beyond what is achievable with an ideal coherent state (a perfect laser) detected with 100% efficient and noiseless detection. We see this absolute improvement for up to 50% absorption, with a maximum observed factor of improvement of 1.46. This equates to around 32% reduction in the total number of photons traversing an optical sample, compared to any future direct optical absorption measurement using classical light.

  8. First absolute mass measurements of short-lived isotopes

    Science.gov (United States)

    Bollen, G.; Dabkiewicz, P.; Egelhof, P.; Hilberath, T.; Kalinowsky, H.; Kern, F.; Schnatz, H.; Schweikhard, L.; Stolzenberg, H.; Moore, R. B.; Kluge, H.-J.; Temmer, G. M.; Ulm, G.

    1987-12-01

    Absolute mass measurements of short-lived isotopes have been performed at the on-line mass separator ISOLDE at CERN by determining the cyclotron frequencies of ions confined in a Penning trap. The cyclotron frequencies for77,78,85,86,88Rb and88Sr ions could be determined with a resolving power of 3×105 and an accuracy of better than 10-6, which corresponds to 100 keV for mass A=100. The shortest-lived isotope under investigation was77Rb with a half-life of 3.7 min. The resonances obtained for the isobars88Rb and88Sr were clearly resolved.

  9. 3D measurement of absolute radiation dose in grid therapy

    Science.gov (United States)

    Trapp, J. V.; Warrington, A. P.; Partridge, M.; Philps, A.; Leach, M. O.; Webb, S.

    2004-01-01

    Spatially fractionated radiotherapy through a grid is a concept which has a long history and was routinely used in orthovoltage radiation therapy in the middle of last century to minimize damage to the skin and subcutaneous tissue. With the advent of megavoltage radiotherapy and its skin sparing effects the use of grids in radiotherapy declined in the 1970s. However there has recently been a revival of the technique for use in palliative treatments with a single fraction of 10 to 20 Gy. In this work the absolute 3D dose distribution in a grid irradiation is measured for photons using a combination of film and gel dosimetry.

  10. An absolute scale for measuring the utility of money

    Science.gov (United States)

    Thomas, P. J.

    2010-07-01

    Measurement of the utility of money is essential in the insurance industry, for prioritising public spending schemes and for the evaluation of decisions on protection systems in high-hazard industries. Up to this time, however, there has been no universally agreed measure for the utility of money, with many utility functions being in common use. In this paper, we shall derive a single family of utility functions, which have risk-aversion as the only free parameter. The fact that they return a utility of zero at their low, reference datum, either the utility of no money or of one unit of money, irrespective of the value of risk-aversion used, qualifies them to be regarded as absolute scales for the utility of money. Evidence of validation for the concept will be offered based on inferential measurements of risk-aversion, using diverse measurement data.

  11. Accurate measurement method for tube's endpoints based on machine vision

    Science.gov (United States)

    Liu, Shaoli; Jin, Peng; Liu, Jianhua; Wang, Xiao; Sun, Peng

    2017-01-01

    Tubes are used widely in aerospace vehicles, and their accurate assembly can directly affect the assembling reliability and the quality of products. It is important to measure the processed tube's endpoints and then fix any geometric errors correspondingly. However, the traditional tube inspection method is time-consuming and complex operations. Therefore, a new measurement method for a tube's endpoints based on machine vision is proposed. First, reflected light on tube's surface can be removed by using photometric linearization. Then, based on the optimization model for the tube's endpoint measurements and the principle of stereo matching, the global coordinates and the relative distance of the tube's endpoint are obtained. To confirm the feasibility, 11 tubes are processed to remove the reflected light and then the endpoint's positions of tubes are measured. The experiment results show that the measurement repeatability accuracy is 0.167 mm, and the absolute accuracy is 0.328 mm. The measurement takes less than 1 min. The proposed method based on machine vision can measure the tube's endpoints without any surface treatment or any tools and can realize on line measurement.

  12. Absolute stress measurements at the rangely anticline, Northwestern Colorado

    Science.gov (United States)

    de la Cruz, R. V.; Raleigh, C.B.

    1972-01-01

    Five different methods of measuring absolute state of stress in rocks in situ were used at sites near Rangely, Colorado, and the results compared. For near-surface measurements, overcoring of the borehole-deformation gage is the most convenient and rapid means of obtaining reliable values for the magnitude and direction of the state of stress in rocks in situ. The magnitudes and directions of the principal stresses are compared to the geologic features of the different areas of measurement. The in situ stresses are consistent in orientation with the stress direction inferred from the earthquake focal-plane solutions and existing joint patterns but inconsistent with stress directions likely to have produced the Rangely anticline. ?? 1972.

  13. Absolute measurement of gene transcripts with Selfie-digital PCR.

    Science.gov (United States)

    Podlesniy, Petar; Trullas, Ramon

    2017-08-21

    Absolute measurement of the number of RNA transcripts per gene is necessary to compare gene transcription among different tissues or experimental conditions and to assess transcription of genes that have a variable copy number per cell such as mitochondrial DNA. Here, we present a method called Selfie-digital PCR that measures the absolute amount of an RNA transcript produced by its own coding DNA at a particular moment. Overcoming the limitations of previous approaches, Selfie-digital PCR allows for the quantification of nuclear and mitochondrial gene transcription in a strand-specific manner that is comparable among tissues and cell types that differ in gene copy number or metabolic state. Using Selfie-digital PCR, we found that, with the exception of the liver, different organs exhibit marked variations in mitochondrial DNA copy number but similar transcription of mitochondrial DNA heavy and light chains, thus suggesting a preferential role of mitochondrial DNA abundance over its transcription in organ function. Moreover, the strand-specific analysis of mitochondrial transcription afforded by Selfie-digital PCR showed that transcription of the heavy strand was significantly higher than that of the light strand in all the tissues studied.

  14. Deconstructing European Poverty Measures: What Relative and Absolute Scales Measure

    Science.gov (United States)

    Burkhauser, Richard V.

    2009-01-01

    Forster and d'Ercole (2009) outline the dominant method of conceptualization and operationalization of European poverty measures that informed the EU in its development of the questionnaire for the European Union--Survey of Income and Living Conditions (EU-SILC). They do so in the context of their explanation of how the Organization for Economic…

  15. Measured and modelled absolute gravity changes in Greenland

    DEFF Research Database (Denmark)

    Nielsen, Jens Emil; Forsberg, René; Strykowski, Gabriel

    2014-01-01

    In glaciated areas, the Earth is responding to the ongoing changes of the ice sheets, a response knownas glacial isostatic adjustment (GIA). GIA can be investigated through observations of gravity change.For the ongoing assessment of the ice sheets mass balance, where satellite data are used......, the study ofGIA is important since it acts as an error source. GIA consists of three signals as seen by a gravimeter onthe surface of the Earth. These signals are investigated in this study. The ICE-5G ice history and recentlydeveloped ice models of present day changes are used to model the gravity change...... in Greenland. Theresult is compared with the initial measurements of absolute gravity (AG) change at selected GreenlandNetwork (GNET) sites.We find that observations are highly influenced by the direct attraction from the ice and ocean. Thisis especially evident in the measurements conducted at the GNET...

  16. Absolute poverty measures for the developing world, 1981–2004

    Science.gov (United States)

    Chen, Shaohua; Ravallion, Martin

    2007-01-01

    We report new estimates of measures of absolute poverty for the developing world for the period 1981–2004. A clear trend decline in the percentage of people who are absolutely poor is evident, although with uneven progress across regions. We find more mixed success in reducing the total number of poor. Indeed, the developing world outside China has seen little or no sustained progress in reducing the number of poor, with rising poverty counts in some regions, notably sub-Saharan Africa. There are encouraging signs of progress in all regions after 2000, although it is too early to say whether this is a new trend. We also summarize results from estimating a new series incorporating an allowance for the higher cost of living facing poor people in urban areas. This reveals a marked urbanization of poverty in the developing world, which is stronger in some regions than others, although it remains that three-quarters of the poor live in rural areas. PMID:17942698

  17. Absolute poverty measures for the developing world, 1981-2004.

    Science.gov (United States)

    Chen, Shaohua; Ravallion, Martin

    2007-10-23

    We report new estimates of measures of absolute poverty for the developing world for the period 1981-2004. A clear trend decline in the percentage of people who are absolutely poor is evident, although with uneven progress across regions. We find more mixed success in reducing the total number of poor. Indeed, the developing world outside China has seen little or no sustained progress in reducing the number of poor, with rising poverty counts in some regions, notably sub-Saharan Africa. There are encouraging signs of progress in all regions after 2000, although it is too early to say whether this is a new trend. We also summarize results from estimating a new series incorporating an allowance for the higher cost of living facing poor people in urban areas. This reveals a marked urbanization of poverty in the developing world, which is stronger in some regions than others, although it remains that three-quarters of the poor live in rural areas.

  18. Absolute measurement method for correction of low-spatial frequency surface figures of aspherics

    Science.gov (United States)

    Lin, Wei-Cheng; Chang, Shenq-Tsong; Ho, Cheng-Fang; Kuo, Ching-Hsiang; Chung, Chien-Kai; Hsu, Wei-Yao; Tseng, Shih-Feng; Sung, Cheng-Kuo

    2017-05-01

    An absolute measurement method involving a computer-generated hologram to facilitate the identification of manufacturing form errors and mounting- and gravity-induced deformations of a 300-mm aspheric mirror is proposed. In this method, the frequency and magnitude of the curve graph plotted from each Zernike coefficient obtained by rotating the mirror with various orientations about optical axis were adopted to distinguish the nonrotationally symmetric aberration. In addition, the random ball test was used to calibrate the rotationally symmetric aberration (spherical aberration). The measured absolute surface figure revealed that a highly accurate aspheric surface with a peak-to-valley value of 1/8 wave at 632.8 nm was realized after the surface figure was corrected using the reconstructed error map.

  19. Absolute standard hydrogen electrode potential measured by reduction of aqueous nanodrops in the gas phase.

    Science.gov (United States)

    Donald, William A; Leib, Ryan D; O'Brien, Jeremy T; Bush, Matthew F; Williams, Evan R

    2008-03-19

    In solution, half-cell potentials are measured relative to those of other half cells, thereby establishing a ladder of thermochemical values that are referenced to the standard hydrogen electrode (SHE), which is arbitrarily assigned a value of exactly 0 V. Although there has been considerable interest in, and efforts toward, establishing an absolute electrochemical half-cell potential in solution, there is no general consensus regarding the best approach to obtain this value. Here, ion-electron recombination energies resulting from electron capture by gas-phase nanodrops containing individual [M(NH3)6]3+, M = Ru, Co, Os, Cr, and Ir, and Cu2+ ions are obtained from the number of water molecules that are lost from the reduced precursors. These experimental data combined with nanodrop solvation energies estimated from Born theory and solution-phase entropies estimated from limited experimental data provide absolute reduction energies for these redox couples in bulk aqueous solution. A key advantage of this approach is that solvent effects well past two solvent shells, that are difficult to model accurately, are included in these experimental measurements. By evaluating these data relative to known solution-phase reduction potentials, an absolute value for the SHE of 4.2 +/- 0.4 V versus a free electron is obtained. Although not achieved here, the uncertainty of this method could potentially be reduced to below 0.1 V, making this an attractive method for establishing an absolute electrochemical scale that bridges solution and gas-phase redox chemistry.

  20. Measured and modelled absolute gravity changes in Greenland

    Science.gov (United States)

    Nielsen, J. Emil; Forsberg, Rene; Strykowski, Gabriel

    2014-01-01

    In glaciated areas, the Earth is responding to the ongoing changes of the ice sheets, a response known as glacial isostatic adjustment (GIA). GIA can be investigated through observations of gravity change. For the ongoing assessment of the ice sheets mass balance, where satellite data are used, the study of GIA is important since it acts as an error source. GIA consists of three signals as seen by a gravimeter on the surface of the Earth. These signals are investigated in this study. The ICE-5G ice history and recently developed ice models of present day changes are used to model the gravity change in Greenland. The result is compared with the initial measurements of absolute gravity (AG) change at selected Greenland Network (GNET) sites.

  1. Absolute interferometric distance measurement using a FM-demodulation technique

    Science.gov (United States)

    Fischer, Edgar; Dalhoff, Ernst; Heim, Silke; Hofbauer, Ulrich; Tiziani, Hans J.

    1995-09-01

    We propose an interferometric method for measuring absolute distances larger than the wavelength. A laser diode is used as a light source. The principle of operation is based on multiple-wavelength interferometry that uses a modulated light source. This method uses the fact that the wavelength of light emitted by the laser diode can be varied by means of the injection current. The modulation of the injection current in combination with the optical heterodyne technique causes a high-frequency phase-modulated detector signal. The phase deviation of the signal is a measure of the optical path difference in the interferometer. By FM demodulation of the detector output with a phase-locked loop demodulator, the optical path difference can be determined directly without the classical ambiguity problem of interferometry. The measuring range in the experiments was limited to 50 mm by the maximum travel range of the used specimen translation stage. Because of the inherent light sensitivity of the method described, the rangefinder can be used for three-dimensional profile measurements on a wide variety of objects, even on diffuse scattering surfaces.

  2. High-precision gravity measurements using absolute and relative gravimeters at Mount Etna (Sicily, Italy

    Directory of Open Access Journals (Sweden)

    Ciro Del Negro

    2011-12-01

    Full Text Available Accurate detection of time gravity changes attributable to the dynamics of volcanoes requires high-precision gravity measurements. With the aim of improving the quality of data from the Mount Etna gravity network, we used both absolute and relative gravimeters in a hybrid method. In this report, some of the techniques for gravity surveys are reviewed, and the results related to each method are compared. We show how the total uncertainty estimated for the gravity measurements performed with this combined use of absolute and relative gravimeters is roughly comparable to that calculated when the measurements are acquired using only relative gravimeters (the traditional method. However, the data highlight how the hybrid approach improves the measurement capabilities for surveying the Mount Etna volcanic area. This approach enhances the accuracy of the data, and then of the four-dimensional surveying, which minimizes ambiguities inherent in the gravity measurements. As a case study, we refer to two gravity datasets acquired in 2005 and 2010 from the western part of the Etna volcano, which included five absolute and 13 relative stations of the Etna gravity network.

  3. An absolute calibration for gas-phase hydroxyl measurements.

    Science.gov (United States)

    Hard, Thomas M; George, Linda A; O'Brien, Robert J

    2002-04-15

    We describe a new method of calibrating tropospheric hydroxyl (OH) instruments. Ozone-alkene mixtures produce steady-state OH radical concentrations. The steady state is governed by competition between OH production in the reaction of ozone with the alkene and OH removal by reactions with the alkene, ozone, and the reactor wall. In a flowtube reactor transporting an ozone-alkene mixture, the OH wall loss rate can be measured by varying the alkene concentration. Delivery of the reaction mixture to the sampling entry of an atmospheric OH measurement instrument provides an absolute calibration of the instrument's response to OH. The present precision of calibration is +/-8% (1-sigma), based on reproducibility over a wide range of ozone concentrations. The accuracy (+/-43%) is limited by uncertainties in kinetic rate coefficients and OH yield, which can be improved. The calibration requires no photon flux measurements or lamp-dependent absorption coefficients, which have inherent, variable, systematic uncertainties, and it has been tested in field experiments.

  4. A measurement of the absolute neutron beam polarization produced by an optically pumped sup 3 He neutron spin filter

    CERN Document Server

    Rich, D R; Crawford, B E; Delheij, P P J; Espy, M A; Haseyama, T; Jones, G; Keith, C D; Knudson, J; Leuschner, M B; Masaike, A; Masuda, Y; Matsuda, Y; Penttilae, S I; Pomeroy, V R; Smith, D A; Snow, W M; Szymanski, J J; Stephenson, S L; Thompson, A K; Yuan, V

    2002-01-01

    The capability of performing accurate absolute measurements of neutron beam polarization opens a number of exciting opportunities in fundamental neutron physics and in neutron scattering. At the LANSCE pulsed neutron source we have measured the neutron beam polarization with an absolute accuracy of 0.3% in the neutron energy range from 40 meV to 10 eV using an optically pumped polarized sup 3 He spin filter and a relative transmission measurement technique. sup 3 He was polarized using the Rb spin-exchange method. We describe the measurement technique, present our results, and discuss some of the systematic effects associated with the method.

  5. Relative Gravity Measurement Campaign during the 8th International Comparison of Absolute Gravimeters (2009)

    Science.gov (United States)

    Jiang, Z.; Pálinkáš, V.; Francis, O.; Jousset, P.; Mäkinen, J.; Merlet, S.; Becker, M.; Coulomb, A.; Kessler-Schulz, K. U.; Schulz, H. R.; Rothleitner, Ch; Tisserand, L.; Lequin, D.

    2012-02-01

    The 8th International Comparison of Absolute Gravimeters (ICAG-2009) and the associated Relative Gravity Campaign (RGC2009) took place at the Bureau International des Poids et Mesures (BIPM) between July and October 2009. Altogether 24 institutes with 22 absolute gravimeters and 9 relative gravimeters participated in the ICAG/RGC campaign. Accurate absolute and relative gravity measurements as well as precision levelling measurements were performed on the micro-gravity 3D-grid at the BIPM. The 2009 comparison was the first to be organized as a Comité International des Poids et Mesures (CIPM) metrological Key Comparison under the CIPM MRA (Mutual Recognition Arrangement), which means that the result will be officially recognized by the governmental organizations responsible. As a consequence, the relative gravimeters employed were carefully selected and the measurement schedules were rigorously enforced compared with earlier campaigns. Thus the quality of the RGC2009 and the determination of the BIPM local gravity network were improved. After 30 years and eight successive ICAGs, the BIPM has decided to transfer its role to the national metrological institutes, although the CIPM will continue to organize the key comparison as ICAGs. The background to the RGC2009, and the organization, data processing and final results of the gravity and vertical gravity gradients, are presented in this paper. This report is more detailed than previous final reports of the RGCs.

  6. 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.

  7. A simple and accurate protocol for absolute polar metabolite quantification in cell cultures using quantitative nuclear magnetic resonance.

    Science.gov (United States)

    Goldoni, Luca; Beringhelli, Tiziana; Rocchia, Walter; Realini, Natalia; Piomelli, Daniele

    2016-05-15

    Absolute analyte quantification by nuclear magnetic resonance (NMR) spectroscopy is rarely pursued in metabolomics, even though this would allow researchers to compare results obtained using different techniques. Here we report on a new protocol that permits, after pH-controlled serum protein removal, the sensitive quantification (limit of detection [LOD] = 5-25 μM) of hydrophilic nutrients and metabolites in the extracellular medium of cells in cultures. The method does not require the use of databases and uses PULCON (pulse length-based concentration determination) quantitative NMR to obtain results that are significantly more accurate and reproducible than those obtained by CPMG (Carr-Purcell-Meiboom-Gill) sequence or post-processing filtering approaches. Three practical applications of the method highlight its flexibility under different cell culture conditions. We identified and quantified (i) metabolic differences between genetically engineered human cell lines, (ii) alterations in cellular metabolism induced by differentiation of mouse myoblasts into myotubes, and (iii) metabolic changes caused by activation of neurotransmitter receptors in mouse myoblasts. Thus, the new protocol offers an easily implementable, efficient, and versatile tool for the investigation of cellular metabolism and signal transduction. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Accurate test limits under nonnormal measurement error

    NARCIS (Netherlands)

    Albers, Willem/Wim; Kallenberg, W.C.M.; Otten, G.D.

    1998-01-01

    When screening a production process for nonconforming items the objective is to improve the average outgoing quality level. Due to measurement errors specification limits cannot be checked directly and hence test limits are required, which meet some given requirement, here given by a prescribed

  9. Accurate Black Hole Spin Measurements using ABC

    Science.gov (United States)

    Connolly, Andrew

    Measuring the spin of black holes provides important insights into the supernova formation mechanism of stellar-mass black holes, galaxy merger scenarios for supermassive black holes, and the launching mechanisms of ballistic jets. It is therefore of crucial importance to measure black hole spins to a high degree of accuracy. Stellar-mass black holes in binary systems (BHBs) have two major advantages over Active Galactic Nuclei (AGN): (1) owing to their proximity and brightness, observations of BHBs are not as limited by counting statistics as their supermassive counter-parts; (2) unlike in AGN, one can use two largely independent methods to measure the spin in BHBs, providing a check on spin measurements. However, the high flux that makes BHBs such excellent targets for spin measurements also proves to be their Achilles heel: modern CCD cameras are optimized for observing faint sources. Consequently, observations of bright BHBs with CCD cameras are subject to non-linear instrumental effects among them pile-up and grade migration that strongly distort the spectrum. Since spin measurements rely on a very precise model of both the continuum X-ray flux and disc reflection signatures superimposed on top of the former, these instrumental effects may cause inferred spin measurements to differ by a factor of two or more. Current mitigation strategies are aimed at removing instrumental effects either during the observations themselves, by requiring simultaneous observations with multiple telescopes, or in post-processing. Even when these techniques are employed, pile-up may remain unrecognized and still distort results, whereas mitigation strategies may introduce additional systematic biases, e.g. due to increased (cross-)calibration uncertainties. Advances in modern statistical methodology allow for efficient modeling of instrumental effects during the analysis stage, largely eliminating the requirements for observations with multiple instruments or increased observation

  10. Accurate phase measurement with classical light

    OpenAIRE

    Wölk, Sabine; Ge, Wenchao; Zubairy, M. Suhail

    2012-01-01

    In this paper we investigate whether it is in general possible to substitute maximally path-entangled states, namely NOON-states by classical light in a Doppleron-type resonant multiphoton detection processes by studying adaptive phase measurement with classical light. We show that multiphoton detection probability using classical light coincides with that of NOON-states and the multiphoton absorbtion rate is not hindered by the spatially unconstrained photons of the classical light in our sc...

  11. Absolute measurement of the Hugoniot and sound velocity of liquid copper at multimegabar pressures

    Science.gov (United States)

    McCoy, Chad A.; Knudson, Marcus D.; Root, Seth

    2017-11-01

    Measurement of the Hugoniot and sound velocity provides information on the bulk modulus and Grüneisen parameter of a material at extreme conditions. The capability to launch multilayered (copper/aluminum) flyer plates at velocities in excess of 20 km/s with the Sandia Z accelerator has enabled high-precision sound-velocity measurements at previously inaccessible pressures. For these experiments, the sound velocity of the copper flyer must be accurately known in the multi-Mbar regime. Here we describe the development of copper as an absolutely calibrated sound-velocity standard for high-precision measurements at pressures in excess of 400 GPa. Using multilayered flyer plates, we performed absolute measurements of the Hugoniot and sound velocity of copper for pressures from 500 to 1200 GPa. These measurements enabled the determination of the Grüneisen parameter for dense liquid copper, clearly showing a density dependence above the melt transition. Combined with earlier data at lower pressures, these results constrain the sound velocity as a function of pressure, enabling the use of copper as a Hugoniot and sound-velocity standard for pressures up to 1200 GPa.

  12. Preliminary results of absolute and high-precision gravity measurements at the Nevada Test Site and vicinity, Nevada

    Science.gov (United States)

    Zumberge, M. A.; Harris, R. N.; Oliver, H. W.; Sasagawa, G. S.; Ponce, D. A.

    Absolute gravity measurements were made at 4 sites in southern Nevada using the absolute gravity free-fall apparatus. Three of the sites are located on the Nevada Test Site at Mercury, Yucca Pass, and in northern Jackass Flats. The fourth site is at Kyle Canyon ranger station near Charleston Park where observed gravity is 216.19 mGal lower than at Mercury. Although there is an uncertainty of about 0.02 mGal in the absolute measured values, their gravity differences are considered accurate to about 0.03 mGal. Therefore, the absolute measurements should provide local control for the calibration of gravity meters between Mercury and Kyle Canyon ranger station to about 1 to 2 parts in 10,000. The average gravity differences between Mercury and Kyle Canyon obtained using LaCoste and Romberg gravity meters is 216.13 mGal, 0.06 mGal lower, or 3 parts in 10,000 lower than using the absolute gravity meter. Because of the discrepancy between the comparison of the absolute and relative gravity meters, more absolute and relative gravity control in southern Nevada, as well as the Mt. Hamilton area where the LaCoste and Romberg instruments were calibrated, is needed. Multiple gravity meter ties were also made between each of the four absolute stations to nearby base stations located on bedrock. These stations were established to help monitor possible real changes in gravity at the absolute sites that could result from seasonal variations in the depth to the water table.

  13. Absolute Position of Targets Measured Through a Chamber Window Using Lidar Metrology Systems

    Science.gov (United States)

    Kubalak, David; Hadjimichael, Theodore; Ohl, Raymond; Slotwinski, Anthony; Telfer, Randal; Hayden, Joseph

    2012-01-01

    Lidar is a useful tool for taking metrology measurements without the need for physical contact with the parts under test. Lidar instruments are aimed at a target using azimuth and elevation stages, then focus a beam of coherent, frequency modulated laser energy onto the target, such as the surface of a mechanical structure. Energy from the reflected beam is mixed with an optical reference signal that travels in a fiber path internal to the instrument, and the range to the target is calculated based on the difference in the frequency of the returned and reference signals. In cases when the parts are in extreme environments, additional steps need to be taken to separate the operator and lidar from that environment. A model has been developed that accurately reduces the lidar data to an absolute position and accounts for the three media in the testbed air, fused silica, and vacuum but the approach can be adapted for any environment or material. The accuracy of laser metrology measurements depends upon knowing the parameters of the media through which the measurement beam travels. Under normal conditions, this means knowledge of the temperature, pressure, and humidity of the air in the measurement volume. In the past, chamber windows have been used to separate the measuring device from the extreme environment within the chamber and still permit optical measurement, but, so far, only relative changes have been diagnosed. The ability to make accurate measurements through a window presents a challenge as there are a number of factors to consider. In the case of the lidar, the window will increase the time-of-flight of the laser beam causing a ranging error, and refract the direction of the beam causing angular positioning errors. In addition, differences in pressure, temperature, and humidity on each side of the window will cause slight atmospheric index changes and induce deformation and a refractive index gradient within the window. Also, since the window is a

  14. Absolute Quantification of Bionanoparticles by Electrospray Differential Mobility Analysis: An Application to Lipoprotein Particle Concentration Measurements.

    Science.gov (United States)

    Clouet-Foraison, Noémie; Gaie-Levrel, Francois; Coquelin, Loic; Ebrard, Géraldine; Gillery, Philippe; Delatour, Vincent

    2017-02-21

    This study presents an upgraded electrospray differential mobility analysis (ES-DMA) setup for the absolute quantification of bionanoparticle concentrations in biological samples, with a special focus on non-high-density-lipoprotein particle concentrations (non-HDL-P). Metrological characterization of the system's analytical performances for concentration measurements shows that the mean intermediate precision relative standard deviation is 14% for biological samples, 6% for silica nanoparticles, and less than 1% for diameter measurements. This study also demonstrates that the most accurate method for non-HDL-P quantification in native serum samples implies daily calculation of the electrospray transmission efficiency (E) of the system with the WHO SP3-08 reference material. The establishment of the uncertainty budget reveals that the main contribution to particle concentration measurement uncertainties is the electrospray transmission efficiency. This data additionally shows that E is not only low (approximately 15-20%) but also highly variable over time and strongly affected by sample composition. This work suggests that absolute enumeration of bionanoparticles is achievable with ES-DMA but provided that a special care is taken to quantifying E with a calibrator of nature and matrix highly similar to the samples ones.

  15. Online absolute pose compensation and steering control of industrial robot based on six degrees of freedom laser measurement

    Science.gov (United States)

    Yang, Juqing; Wang, Dayong; Fan, Baixing; Dong, Dengfeng; Zhou, Weihu

    2017-03-01

    In-situ intelligent manufacturing for large-volume equipment requires industrial robots with absolute high-accuracy positioning and orientation steering control. Conventional robots mainly employ an offline calibration technology to identify and compensate key robotic parameters. However, the dynamic and static parameters of a robot change nonlinearly. It is not possible to acquire a robot's actual parameters and control the absolute pose of the robot with a high accuracy within a large workspace by offline calibration in real-time. This study proposes a real-time online absolute pose steering control method for an industrial robot based on six degrees of freedom laser tracking measurement, which adopts comprehensive compensation and correction of differential movement variables. First, the pose steering control system and robot kinematics error model are constructed, and then the pose error compensation mechanism and algorithm are introduced in detail. By accurately achieving the position and orientation of the robot end-tool, mapping the computed Jacobian matrix of the joint variable and correcting the joint variable, the real-time online absolute pose compensation for an industrial robot is accurately implemented in simulations and experimental tests. The average positioning error is 0.048 mm and orientation accuracy is better than 0.01 deg. The results demonstrate that the proposed method is feasible, and the online absolute accuracy of a robot is sufficiently enhanced.

  16. A proposal to measure absolute environmental sustainability in lifecycle assessment

    DEFF Research Database (Denmark)

    Bjørn, Anders; Margni, Manuele; Roy, Pierre-Olivier

    2016-01-01

    Environmental monitoring indicates that progress towards the goal of environmental sustainability in many cases is slow, non-existing or negative. Indicators that use environmental carrying capacity references to evaluate whether anthropogenic systems are, or will potentially be, environmentally......) can potentially reduce or eliminate these shortcomings. We developed a generic mathematical framework for the use of carrying capacity as environmental sustainability reference in spatially resolved life cycle impact assessment models and applied this framework to the LCA impact category terrestrial...... in supporting decisions aimed at simultaneously reducing environmental impacts efficiently and maintaining or achieving environmental sustainability. We have demonstrated that LCA indicators can be modified from being relative to being absolute indicators of environmental sustainability. Further research should...

  17. An absolute cavity pyrgeometer to measure the absolute outdoor longwave irradiance with traceability to international system of units, SI

    Science.gov (United States)

    Reda, Ibrahim; Zeng, Jinan; Scheuch, Jonathan; Hanssen, Leonard; Wilthan, Boris; Myers, Daryl; Stoffel, Tom

    2012-03-01

    This article describes a method of measuring the absolute outdoor longwave irradiance using an absolute cavity pyrgeometer (ACP), U.S. Patent application no. 13/049, 275. The ACP consists of domeless thermopile pyrgeometer, gold-plated concentrator, temperature controller, and data acquisition. The dome was removed from the pyrgeometer to remove errors associated with dome transmittance and the dome correction factor. To avoid thermal convection and wind effect errors resulting from using a domeless thermopile, the gold-plated concentrator was placed above the thermopile. The concentrator is a dual compound parabolic concentrator (CPC) with 180° view angle to measure the outdoor incoming longwave irradiance from the atmosphere. The incoming irradiance is reflected from the specular gold surface of the CPC and concentrated on the 11 mm diameter of the pyrgeometer's blackened thermopile. The CPC's interior surface design and the resulting cavitation result in a throughput value that was characterized by the National Institute of Standards and Technology. The ACP was installed horizontally outdoor on an aluminum plate connected to the temperature controller to control the pyrgeometer's case temperature. The responsivity of the pyrgeometer's thermopile detector was determined by lowering the case temperature and calculating the rate of change of the thermopile output voltage versus the changing net irradiance. The responsivity is then used to calculate the absolute atmospheric longwave irradiance with an uncertainty estimate (U95) of ±3.96 W m-2 with traceability to the International System of Units, SI. The measured irradiance was compared with the irradiance measured by two pyrgeometers calibrated by the World Radiation Center with traceability to the Interim World Infrared Standard Group, WISG. A total of 408 readings were collected over three different nights. The calculated irradiance measured by the ACP was 1.5 W/m2 lower than that measured by the two

  18. Ross filter development for absolute measurement of Al line radiation on MST

    Science.gov (United States)

    Lauersdorf, N.; Reusch, L. M.; den Hartog, D. J.; Goetz, J. A.; Franz, P.; Vanmeter, P.

    2017-10-01

    The MST has a two-color soft x-ray tomography (SXT) diagnostic that, using the double-filter technique, measures electron temperature (Te) from the slope of the soft x-ray (SXR) continuum. Because MST has an aluminum plasma-facing surface, bright Al line radiation occurs in the SXR spectrum. In past application of the double-filter technique, these lines have been filtered out using thick Be filters ( 400 μm and 800 μm), restricting the measurement temperature range to >=1 keV due to the signal strength having a positive correlation with Te. Another way to deal with the line radiation is to explicitly include it into the SXR spectrum analysis from which Te is derived. A Ross filter set has been designed to measure this line radiation, and will enable the absolute intensities of the aluminum lines to be quantified and incorporated into the analysis. The Ross filter will be used to measure Al+11 and Al+12 lines, occurring between 1.59 and 2.04 keV. By using multiple detectors with filters made of varying element concentrations, we create spectral bins in which the dominant transmission is the line radiation. Absolute measurement of Al line intensities will enable use of thinner filters in the SXT diagnostic and accurate measurement of Te < 1 keV. This material is based upon work supported by the U.S. Department of Energy Office of Science, Office of Fusion Energy Sciences program under Award Numbers DE-FC02-05ER54814 and DE-SC0015474.

  19. Absolute beam emittance measurements at RHIC using ionization profile monitors

    Energy Technology Data Exchange (ETDEWEB)

    Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Connolly, R [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Summers, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Tepikian, S. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-08-15

    In the past, comparisons between emittance measurements obtained using ionization profile monitors, Vernier scans (using as input the measured rates from the zero degree counters, or ZDCs), the polarimeters and the Schottky detectors evidenced significant variations of up to 100%. In this report we present studies of the RHIC ionization profile monitors (IPMs). After identifying and correcting for two systematic instrumental errors in the beam size measurements, we present experimental results showing that the remaining dominant error in beam emittance measurements at RHIC using the IPMs was imprecise knowledge of the local beta functions. After removal of the systematic errors and implementation of measured beta functions, precise emittance measurements result. Also, consistency between the emittances measured by the IPMs and those derived from the ZDCs was demonstrated.

  20. Absolute quantum yield measurements for the formation of oxygen ...

    Indian Academy of Sciences (India)

    ... under collision-free conditions by vacuum ultraviolet laser-induced fluorescence. The use of narrow-band probe laser radiation, generated via resonant third-order sum-difference frequency conversion of dye laser radiation in Krypton, allowed the measurement of the nascent O(3P=2,1,0) fine-structure state distribution: ...

  1. Absolute quantum yield measurements for the formation of oxygen ...

    Indian Academy of Sciences (India)

    Unknown

    -BAJEHa ... third-order sum-difference frequency conversion of dye laser radiation in Krypton, allowed the measurement of the ... combustion in power plants, is the largest individual source of sulphur in the earth's troposphere.1 Due to its ...

  2. Relative versus absolute measures of explicit attitudes: Implications for predicting diverse attitude-relevant criteria.

    Science.gov (United States)

    Olson, James M; Goffin, Richard D; Haynes, Graeme A

    2007-12-01

    The authors report 4 studies exploring a self-report strategy for measuring explicit attitudes that uses "relative" ratings, in which respondents indicate how favorable or unfavorable they are compared with other people. Results consistently showed that attitudes measured with relative scales predicted relevant criterion variables (self-report of behavior, measures of knowledge, peer ratings of attitudes, peer ratings of behavior) better than did attitudes measured with more traditional "absolute" scales. The obtained pattern of differences in prediction by relative versus absolute measures of attitudes did not appear to be attributable to differential variability, social desirability effects, the clarity of scale-point meanings, the number of scale points, or overlap with subjective norms. The final study indicated that relative measures induce respondents to consider social comparison information and behavioral information when making their responses more than do absolute measures, which may explain the higher correlations between relative measures of attitudes and relevant criteria. (c) 2007 APA, all rights reserved.

  3. 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,…

  4. Accurate measurement of streamwise vortices using dual-plane PIV

    Science.gov (United States)

    Waldman, Rye M.; Breuer, Kenneth S.

    2012-11-01

    Low Reynolds number aerodynamic experiments with flapping animals (such as bats and small birds) are of particular interest due to their application to micro air vehicles which operate in a similar parameter space. Previous PIV wake measurements described the structures left by bats and birds and provided insight into the time history of their aerodynamic force generation; however, these studies have faced difficulty drawing quantitative conclusions based on said measurements. The highly three-dimensional and unsteady nature of the flows associated with flapping flight are major challenges for accurate measurements. The challenge of animal flight measurements is finding small flow features in a large field of view at high speed with limited laser energy and camera resolution. Cross-stream measurement is further complicated by the predominately out-of-plane flow that requires thick laser sheets and short inter-frame times, which increase noise and measurement uncertainty. Choosing appropriate experimental parameters requires compromise between the spatial and temporal resolution and the dynamic range of the measurement. To explore these challenges, we do a case study on the wake of a fixed wing. The fixed model simplifies the experiment and allows direct measurements of the aerodynamic forces via load cell. We present a detailed analysis of the wake measurements, discuss the criteria for making accurate measurements, and present a solution for making quantitative aerodynamic load measurements behind free-flyers.

  5. Absolute measurement of rates of capture of neutrons in 238U and fission in 239Pu

    Science.gov (United States)

    Dulin, V. A.

    1981-04-01

    The absolute rate of capture of neutrons in U-238 was measured in terms of the Np-239 activity found (gamma radiation), using a calibrated Am-243 source to determine the efficiency of gamma recording in the detector. The absolute rate of fission of Pu-239 was determined by means of a fission chamber with a known number of Pu-239 nuclei, and the efficiency of fission fragment recording in the chamber was calculated.

  6. Contributing to a precise and accurate chronostratigraphic time scale for climatic records: Absolute dating and paleomagnetism in lavas

    Science.gov (United States)

    Sasco, Romain; Guillou, Herve; Kissel, Catherine; Wandres, Camille; Carracedo, Juan-Carlos; Perez Torrado, Francisco Jose

    2014-05-01

    Understanding climatic mechanisms requires a robust and precise timescale allowing long-distance and multi-archives correlations. A unique tool to construct such time scales is provided by the Earth magnetic field (EMF), which is independent from climatic variations and the past evolution of which is recorded in most of the geological/climatic archives. Sedimentary sequences provide continuous records of relative intensities of the EMF on stratigraphic time scales, usually based on orbital tuning. They are transferred onto absolute intensity scale and chronological time scale using robust tie points available for the past ~40 ka. However, for older periods this calibration remains poorly constrained. Our study reports on new tie points over the last 200 ka by combining paleomagnetic and geochronological (K/Ar and 40Ar-39Ar dating) studies on lavas. Based on the K-Ar LSCE age database, a set of 18 lava flows corresponding to potential geomagnetic excursions and/or highs and lows in the paleomagnetic intensity as observed from sediments and occurring in the studied time-window were selected in the Canary Islands (Tenerife, La Palma and Gran Canaria). A total of 205 oriented cores were taken from these 18 lava flows. Rock magnetic experiments include thermomagnetic analyses on each core, hysteresis loop and First Order Reversal Curves. Stepwise thermal demagnetizations in zero-field provided reliable mean-site paleomagnetic direction of the EMF for 15 of the flows. Paleointensity values were determined using the original Thellier and Thellier method. Based on previous experiments, 170 samples were analyzed, among which 51% provided reliable paleointensity values (determined using PICRIT-03 criteria). The geochronological study focused on 40Ar-39Ar dating. Based on preliminary paleomagnetic results, 13 flows were analyzed and 11 provided ages consistent at the 2 sigma level with the already available K-Ar ages. This coupled K/Ar - 40Ar-39Ar results strongly constrain

  7. Measurement of absolute optical thickness of mask glass by wavelength-tuning Fourier analysis.

    Science.gov (United States)

    Kim, Yangjin; Hbino, Kenichi; Sugita, Naohiko; Mitsuishi, Mamoru

    2015-07-01

    Optical thickness is a fundamental characteristic of an optical component. A measurement method combining discrete Fourier-transform (DFT) analysis and a phase-shifting technique gives an appropriate value for the absolute optical thickness of a transparent plate. However, there is a systematic error caused by the nonlinearity of the phase-shifting technique. In this research the absolute optical-thickness distribution of mask blank glass was measured using DFT and wavelength-tuning Fizeau interferometry without using sensitive phase-shifting techniques. The error occurring during the DFT analysis was compensated for by using the unwrapping correlation. The experimental results indicated that the absolute optical thickness of mask glass was measured with an accuracy of 5 nm.

  8. Calibration Techniques for Accurate Measurements by Underwater Camera Systems

    Science.gov (United States)

    Shortis, Mark

    2015-01-01

    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. PMID:26690172

  9. A method for accurate temperature measurement using infrared thermal camera.

    Science.gov (United States)

    Tokunaga, Tomoharu; Narushima, Takashi; Yonezawa, Tetsu; Sudo, Takayuki; Okubo, Shuichi; Komatsubara, Shigeyuki; Sasaki, Katsuhiro; Yamamoto, Takahisa

    2012-08-01

    The temperature distribution on a centre-holed thin foil of molybdenum, used as a sample and heated using a sample-heating holder for electron microscopy, was measured using an infrared thermal camera. The temperature on the heated foil area located near the heating stage of the heating holder is almost equal to the temperature on the heating stage. However, during the measurement of the temperature at the edge of the hole of the foil located farthest from the heating stage, a drop in temperature should be taken into consideration; however, so far, no method has been developed to locally measure the temperature distribution on the heated sample. In this study, a method for the accurate measurement of temperature distribution on heated samples for electron microscopy is discussed.

  10. Precise and accurate isotopic measurements using multiple-collector ICPMS

    Science.gov (United States)

    Albarède, F.; Telouk, Philippe; Blichert-Toft, Janne; Boyet, Maud; Agranier, Arnaud; Nelson, Bruce

    2004-06-01

    New techniques of isotopic measurements by a new generation of mass spectrometers equipped with an inductively-coupled-plasma source, a magnetic mass filter, and multiple collection (MC-ICPMS) are quickly developing. These techniques are valuable because of (1) the ability of ICP sources to ionize virtually every element in the periodic table, and (2) the large sample throughout. However, because of the complex trajectories of multiple ion beams produced in the plasma source whether from the same or different elements, the acquisition of precise and accurate isotopic data with this type of instrument still requires a good understanding of instrumental fractionation processes, both mass-dependent and mass-independent. Although physical processes responsible for the instrumental mass bias are still to be understood more fully, we here present a theoretical framework that allows for most of the analytical limitations to high precision and accuracy to be overcome. After a presentation of unifying phenomenological theory for mass-dependent fractionation in mass spectrometers, we show how this theory accounts for the techniques of standard bracketing and of isotopic normalization by a ratio of either the same or a different element, such as the use of Tl to correct mass bias on Pb. Accuracy is discussed with reference to the concept of cup efficiencies. Although these can be simply calibrated by analyzing standards, we derive a straightforward, very general method to calculate accurate isotopic ratios from dynamic measurements. In this study, we successfully applied the dynamic method to Nd and Pb as examples. We confirm that the assumption of identical mass bias for neighboring elements (notably Pb and Tl, and Yb and Lu) is both unnecessary and incorrect. We further discuss the dangers of straightforward standard-sample bracketing when chemical purification of the element to be analyzed is imperfect. Pooling runs to improve precision is acceptable provided the pooled

  11. 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...... with a decrease in the response time of the gas analyzer. When only CBL was present, shorter measurement time was needed for the accurate concentration measurement of the tracer gas released close to the breathing zone. For more complex flow, as a result of CBL interaction with the exhalation flow, the needed...

  12. Accurate mass measurements on neutron-deficient krypton isotopes

    CERN Document Server

    Rodríguez, D.; Äystö, J.; Beck, D.; Blaum, K.; Bollen, G.; Herfurth, F.; Jokinen, A.; Kellerbauer, A.; Kluge, H.-J.; Kolhinen, V.S.; Oinonen, M.; Sauvan, E.; Schwarz, S.

    2006-01-01

    The masses of $^{72–78,80,82,86}$Kr were measured directly with the ISOLTRAP Penning trap mass spectrometer at ISOLDE/CERN. For all these nuclides, the measurements yielded mass uncertainties below 10 keV. The ISOLTRAP mass values for $^{72–75}$Kr being more precise than the previous results obtained by means of other techniques, and thus completely determine the new values in the Atomic-Mass Evaluation. Besides the interest of these masses for nuclear astrophysics, nuclear structure studies, and Standard Model tests, these results constitute a valuable and accurate input to improve mass models. In this paper, we present the mass measurements and discuss the mass evaluation for these Kr isotopes.

  13. Electron cyclotron emission measurements on JET: Michelson interferometer, new absolute calibration, and determination of electron temperature

    NARCIS (Netherlands)

    Schmuck, S.; Fessey, J.; Gerbaud, T.; Alper, B.; Beurskens, M. N. A.; de la Luna, E.; Sirinelli, A.; Zerbini, M.

    2012-01-01

    At the fusion experiment JET, a Michelson interferometer is used to measure the spectrum of the electron cyclotron emission in the spectral range 70-500 GHz. The interferometer is absolutely calibrated using the hot/cold technique and, in consequence, the spatial profile of the plasma electron

  14. On the absolute measure of Beta activities; Sobre la medida absoluta de actividades Beta

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez del Rio, C.; Jimenez Reynaldo, O.; Rodriguez Mayquez, E.

    1956-07-01

    A new method for absolute beta counting of solid samples is given. The measurements is made with an inside Geiger-Muller tube of new construction. The backscattering correction when using an infinite thick mounting is discussed and results for different materials given. (Author)

  15. Demonstrating the Error Budget for the Climate Absolute Radiance and Refractivity Observatory Through Solar Irradiance Measurements

    Science.gov (United States)

    Thome, Kurtis; McCorkel, Joel; McAndrew, Brendan

    2016-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission addresses the need to observe highaccuracy, long-term climate change trends and to use decadal change observations as a method to determine the accuracy of climate change. A CLARREO objective is to improve the accuracy of SI-traceable, absolute calibration at infrared and reflected solar wavelengths to reach on-orbit accuracies required to allow climate change observations to survive data gaps and observe climate change at the limit of natural variability. Such an effort will also demonstrate National Institute of Standards and Technology (NIST) approaches for use in future spaceborne instruments. The current work describes the results of laboratory and field measurements with the Solar, Lunar for Absolute Reflectance Imaging Spectroradiometer (SOLARIS) which is the calibration demonstration system (CDS) for the reflected solar portion of CLARREO. SOLARIS allows testing and evaluation of calibration approaches, alternate design and/or implementation approaches and components for the CLARREO mission. SOLARIS also provides a test-bed for detector technologies, non-linearity determination and uncertainties, and application of future technology developments and suggested spacecraft instrument design modifications. Results of laboratory calibration measurements are provided to demonstrate key assumptions about instrument behavior that are needed to achieve CLARREO's climate measurement requirements. Absolute radiometric response is determined using laser-based calibration sources and applied to direct solar views for comparison with accepted solar irradiance models to demonstrate accuracy values giving confidence in the error budget for the CLARREO reflectance retrieval.

  16. 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.

  17. 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

  18. New design and facilities for the International Database for Absolute Gravity Measurements (AGrav): A support for the Establishment of a new Global Absolute Gravity Reference System

    Science.gov (United States)

    Wziontek, Hartmut; Falk, Reinhard; Bonvalot, Sylvain; Rülke, Axel

    2017-04-01

    After about 10 years of successful joint operation by BGI and BKG, the International Database for Absolute Gravity Measurements "AGrav" (see references hereafter) was under a major revision. The outdated web interface was replaced by a responsive, high level web application framework based on Python and built on top of Pyramid. Functionality was added, like interactive time series plots or a report generator and the interactive map-based station overview was updated completely, comprising now clustering and the classification of stations. Furthermore, the database backend was migrated to PostgreSQL for better support of the application framework and long-term availability. As comparisons of absolute gravimeters (AG) become essential to realize a precise and uniform gravity standard, the database was extended to document the results on international and regional level, including those performed at monitoring stations equipped with SGs. By this it will be possible to link different AGs and to trace their equivalence back to the key comparisons under the auspices of International Committee for Weights and Measures (CIPM) as the best metrological realization of the absolute gravity standard. In this way the new AGrav database accommodates the demands of the new Global Absolute Gravity Reference System as recommended by the IAG Resolution No. 2 adopted in Prague 2015. The new database will be presented with focus on the new user interface and new functionality, calling all institutions involved in absolute gravimetry to participate and contribute with their information to built up a most complete picture of high precision absolute gravimetry and improve its visibility. A Digital Object Identifier (DOI) will be provided by BGI to contributors to give a better traceability and facilitate the referencing of their gravity surveys. Links and references: BGI mirror site : http://bgi.obs-mip.fr/data-products/Gravity-Databases/Absolute-Gravity-data/ BKG mirror site: http

  19. Accurate mass measurements of very short-lived nuclei

    CERN Document Server

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

    2002-01-01

    Mass measurements of /sup 34/Ar, /sup 73-78/Kr, and /sup 74,76/Rb were performed with the Penning-trap mass spectrometer ISOLTRAP. Very accurate Q/sub EC/-values are needed for the investigations of the F /sub t/-value of 0/sup +/ to 0/sup +/ nuclear beta -decays used to test the standard model predictions for weak interactions. The necessary accuracy on the Q/sub EC/-value requires the mass of mother and daughter nuclei to be measured with delta m/mmeasured nuclides presented here this has been reached. The /sup 34/Ar mass has been measured with a relative accuracy of 1.1.10/sup -8/. The Q/sub EC/-value of the /sup 34/Ar 0 /sup +/ to 0/sup +/ decay can now he determined with an uncertainty of about 0.01%. Furthermore, /sup 74/Rb is the shortest-lived nuclide ever investigated in a Penning trap. (18 refs).

  20. Accurate measurement of streamwise vortices in low speed aerodynamic flows

    Science.gov (United States)

    Waldman, Rye M.; Kudo, Jun; Breuer, Kenneth S.

    2010-11-01

    Low Reynolds number experiments with flapping animals (such as bats and small birds) are of current interest in understanding biological flight mechanics, and due to their application to Micro Air Vehicles (MAVs) which operate in a similar parameter space. Previous PIV wake measurements have described the structures left by bats and birds, and provided insight to the time history of their aerodynamic force generation; however, these studies have faced difficulty drawing quantitative conclusions due to significant experimental challenges associated with the highly three-dimensional and unsteady nature of the flows, and the low wake velocities associated with lifting bodies that only weigh a few grams. This requires the high-speed resolution of small flow features in a large field of view using limited laser energy and finite camera resolution. Cross-stream measurements are further complicated by the high out-of-plane flow which requires thick laser sheets and short interframe times. To quantify and address these challenges we present data from a model study on the wake behind a fixed wing at conditions comparable to those found in biological flight. We present a detailed analysis of the PIV wake measurements, discuss the criteria necessary for accurate measurements, and present a new dual-plane PIV configuration to resolve these issues.

  1. 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)

  2. Absolute gravity measurements at three sites characterized by different environmental conditions using two portable ballistic gravimeters

    Science.gov (United States)

    Greco, Filippo; Biolcati, Emanuele; Pistorio, Antonio; D'Agostino, Giancarlo; Germak, Alessandro; Origlia, Claudio; Del Negro, Ciro

    2015-03-01

    The performances of two absolute gravimeters at three different sites in Italy between 2009 and 2011 is presented. The measurements of the gravity acceleration g were performed using the absolute gravimeters Micro-g LaCoste FG5#238 and the INRiM prototype IMGC-02, which represent the state of the art in ballistic gravimeter technology (relative uncertainty of a few parts in 109). For the comparison, the measured g values were reported at the same height by means of the vertical gravity gradient estimated at each site with relative gravimeters. The consistency and reliability of the gravity observations, as well as the performance and efficiency of the instruments, were assessed by measurements made in sites characterized by different logistics and environmental conditions. Furthermore, the various factors affecting the measurements and their uncertainty were thoroughly investigated. The measurements showed good agreement, with the minimum and maximum differences being 4.0 and 8.3 μGal. The normalized errors are very much lower than 1, ranging between 0.06 and 0.45, confirming the compatibility between the results. This excellent agreement can be attributed to several factors, including the good working order of gravimeters and the correct setup and use of the instruments in different conditions. These results can contribute to the standardization of absolute gravity surveys largely for applications in geophysics, volcanology and other branches of geosciences, allowing achieving a good trade-off between uncertainty and efficiency of gravity measurements.

  3. Accurate measure by weight of liquids in industry. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Muller, M.R.

    1992-12-12

    This research`s focus was to build a prototype of a computerized liquid dispensing system. This liquid metering system is based on the concept of altering the representative volume to account for temperature changes in the liquid to be dispensed. This is actualized by using a measuring tank and a temperature compensating displacement plunger. By constantly monitoring the temperature of the liquid, the plunger can be used to increase or decrease the specified volume to more accurately dispense liquid with a specified mass. In order to put the device being developed into proper engineering perspective, an extensive literature review was undertaken on all areas of industrial metering of liquids with an emphasis on gravimetric methods.

  4. Accurate measure by weight of liquids in industry

    Energy Technology Data Exchange (ETDEWEB)

    Muller, M.R.

    1992-12-12

    This research's focus was to build a prototype of a computerized liquid dispensing system. This liquid metering system is based on the concept of altering the representative volume to account for temperature changes in the liquid to be dispensed. This is actualized by using a measuring tank and a temperature compensating displacement plunger. By constantly monitoring the temperature of the liquid, the plunger can be used to increase or decrease the specified volume to more accurately dispense liquid with a specified mass. In order to put the device being developed into proper engineering perspective, an extensive literature review was undertaken on all areas of industrial metering of liquids with an emphasis on gravimetric methods.

  5. Electron Microprobe Analysis Techniques for Accurate Measurements of Apatite

    Science.gov (United States)

    Goldoff, B. A.; Webster, J. D.; Harlov, D. E.

    2010-12-01

    Apatite [Ca5(PO4)3(F, Cl, OH)] is a ubiquitous accessory mineral in igneous, metamorphic, and sedimentary rocks. The mineral contains halogens and hydroxyl ions, which can provide important constraints on fugacities of volatile components in fluids and other phases in igneous and metamorphic environments in which apatite has equilibrated. Accurate measurements of these components in apatite are therefore necessary. Analyzing apatite by electron microprobe (EMPA), which is a commonly used geochemical analytical technique, has often been found to be problematic and previous studies have identified sources of error. For example, Stormer et al. (1993) demonstrated that the orientation of an apatite grain relative to the incident electron beam could significantly affect the concentration results. In this study, a variety of alternative EMPA operating conditions for apatite analysis were investigated: a range of electron beam settings, count times, crystal grain orientations, and calibration standards were tested. Twenty synthetic anhydrous apatite samples that span the fluorapatite-chlorapatite solid solution series, and whose halogen concentrations were determined by wet chemistry, were analyzed. Accurate measurements of these samples were obtained with many EMPA techniques. One effective method includes setting a static electron beam to 10-15nA, 15kV, and 10 microns in diameter. Additionally, the apatite sample is oriented with the crystal’s c-axis parallel to the slide surface and the count times are moderate. Importantly, the F and Cl EMPA concentrations are in extremely good agreement with the wet-chemical data. We also present EMPA operating conditions and techniques that are problematic and should be avoided. J.C. Stormer, Jr. et al., Am. Mineral. 78 (1993) 641-648.

  6. Measuring the absolute DT neutron yield using the Magnetic Recoil Spectrometer at OMEGA and the NIF

    Energy Technology Data Exchange (ETDEWEB)

    Mackinnon, A; Casey, D; Frenje, J A; Johnson, M G; Seguin, F H; Li, C K; Petrasso, R D; Glebov, V Y; Katz, J; Knauer, J; Meyerhofer, D; Sangster, T; Bionta, R; Bleuel, D; Hachett, S P; Hartouni, E; Lepape, S; Mckernan, M; Moran, M; Yeamans, C

    2012-05-03

    A Magnetic Recoil Spectrometer (MRS) has been installed and extensively used on OMEGA and the National Ignition Facility (NIF) for measurements of the absolute neutron spectrum from inertial confinement fusion (ICF) implosions. From the neutron spectrum measured with the MRS, many critical implosion parameters are determined including the primary DT neutron yield, the ion temperature, and the down-scattered neutron yield. As the MRS detection efficiency is determined from first principles, the absolute DT neutron yield is obtained without cross-calibration to other techniques. The MRS primary DT neutron measurements at OMEGA and the NIF are shown to be in excellent agreement with previously established yield diagnostics on OMEGA, and with the newly commissioned nuclear activation diagnostics on the NIF.

  7. Three-dimensional electromagnetic-model-based absolute attitude measurement using monostatic wideband radar

    Science.gov (United States)

    Yang, XiaoLiang; Wen, GongJian; Ma, CongHui; Hui, BingWei

    2017-01-01

    This paper proposes an absolute attitude measurement approach by utilizing a monostatic wideband radar. In this approach, the three-dimensional electromagnetic-model (3-D em-model) and the parametric motion model of a target are combined to estimate absolute attitude. The 3-D em-model is established offline based on the target's geometric structure. Scattering characteristics such as radar cross section and radar images from one-dimension to 3-D can be conveniently predicted by this model. By matching the high-resolution range profiles (HRRPs) of measurements with the HRRPs predicted by the 3-D em-model, the directions of the lines of sight relative to the target at different measuring times are first obtained. Then, based on the obtained directions and the parametric motion model of the target, the target absolute attitude at each measuring time can be acquired. Experiments using both data predicted by a high-frequency em-code and data measured in an anechoic chamber verify the validity of the proposed method.

  8. Schiotz tonometry accurately measures intraocular pressure in Boston type 1 keratoprosthesis eyes.

    Science.gov (United States)

    Estrovich, Igor E; Shen, Chris; Chu, Yvonne; Downs, J Crawford; Gardiner, Stuart; Straiko, Michael; Mansberger, Steven L

    2015-06-01

    To evaluate the location of the eye and tonometry device that provides the most accurate intraocular pressure (IOP) measurements in eyes with Boston type 1 keratoprosthesis. A single surgeon sutured a Boston keratoprosthesis into the central cornea in the usual manner in 5 eyes of deceased donors. Another investigator used a 27-gauge needle, digital manometry, and gravity infusion to set the IOP at levels of 10, 20, 30, and 40 mm Hg in random order. A second investigator masked to the level of IOP used a Schiotz tonometer (Sklar) with a 7.5-g plunger load and a Tono-pen XL tonometer (Medtronic) to determine IOP at the temporal corneoscleral limbus and temporal sclera (3 mm temporal to the corneoscleral limbus). We used generalized estimation equation models to determine an average absolute difference between the tonometer measurements compared with the "gold standard" digital manometric IOP. The Schiotz tonometer had a lower median absolute error compared with the Tono-pen at both temporal sclera (5.4 mm Hg vs. 39.0 mm Hg, P keratoprosthesis.

  9. Laser induced deflection technique for absolute thin film absorption measurement: optimized concepts and experimental results.

    Science.gov (United States)

    Mühlig, Christian; Kufert, Siegfried; Bublitz, Simon; Speck, Uwe

    2011-03-20

    Using experimental results and numerical simulations, two measuring concepts of the laser induced deflection (LID) technique are introduced and optimized for absolute thin film absorption measurements from deep ultraviolet to IR wavelengths. For transparent optical coatings, a particular probe beam deflection direction allows the absorption measurement with virtually no influence of the substrate absorption, yielding improved accuracy compared to the common techniques of separating bulk and coating absorption. For high-reflection coatings, where substrate absorption contributions are negligible, a different probe beam deflection is chosen to achieve a better signal-to-noise ratio. Various experimental results for the two different measurement concepts are presented.

  10. 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

  11. A novel technique for highly accurate gas exchange measurements

    Science.gov (United States)

    Kalkenings, R. K.; Jähne, B. J.

    2003-04-01

    The Heidelberg Aeolotron is a circular wind-wave facility for investigating air-sea gas exchange. In this contribution a novel technique for measuring highly accurate transfer velocities k of mass transfer will be presented. Traditionally, in mass balance techniques the constant of decay for gas concentrations over time is measured. The major drawback of this concept is the long time constant. At low wind speeds and a water height greater than 1 m the period of observation has to be several days. In a gas-tight facility such as the Aeolotron, the transfer velocity k can be computed from the concentration in the water body and the change of concentration in the gas space. Owing to this fact, transfer velocities are gained while greatly reducing the measuring times to less than one hour. The transfer velocity k of a tracer can be parameterized as k=1/β \\cdot u_* \\cdot Sc^n, with the Schmidt Number Sc, shear velocity u_* and the dimensionless transfer resistance β. The Schmidt Number exponent n can be derived from simultaneous measurements of different tracers. Since these tracers are of different Schmidt number, the shear velocity is not needed. To allow for Schmidt numbers spanning a hole decade, in our experiments He, H_2, N_2O and F12 are used. The relative accuracy of measuring the transfer velocity was improved to less than 2%. In 9 consecutive experiments conducted at a wind speed of 6.2 m/s, the deviation of the Schmidt number exponent was found to be just under 0.02. This high accuracy will allow precisely determining the transition of the Schmidt number exponent from n=2/3 to n=0.5 from a flat to wavy water surface. In order to quantify gas exchange not only the wind speed is important. Surfactants have a pronounced effect on the wave field and lead to a drastic reduction in the transfer velocity. In the Aeolotron measurements were conducted with a variety of measuring devices, ranging from an imaging slope gauge (ISG) to thermal techniques with IR

  12. Absolute measurement of the $\\beta\\alpha$ decay of $^{16}$N

    CERN Multimedia

    We propose to study the $\\beta$-decay of $^{16}$N at ISOLDE with the aim of determining the branching ratio for $\\beta\\alpha$ decay on an absolute scale. There are indications that the previously measured branching ratio is in error by an amount significantly larger than the quoted uncertainty. This limits the precision with which the S-factor of the astrophysically important $^{12}$C($\\alpha, \\gamma)^{16}$O reaction can be determined.

  13. Absolute Branching Fraction Measurements for Exclusive $D_s$ Semileptonic Decays

    CERN Document Server

    Yelton, J

    2009-01-01

    We measure the absolute branching fractions of $\\Ds$ semileptonic decays where the hadron in the final state is one of $\\phi$, $\\eta$, $\\etap$, $\\Ks$, $\\Kstar$, and $f_0$, using $2.8 \\times 10^5$ $\\epm \\to \\Ds\\Dsstar$ decays collected in the CLEO-c detector at a center-of-mass energy close to 4170 MeV. We obtain ${\\cal B}(\\Dsp\\to \\phi e^+ \

  14. Measurement of definite integral of sinusoidal signal absolute value third power using digital stochastic method

    Directory of Open Access Journals (Sweden)

    Beljić Željko

    2017-01-01

    Full Text Available In this paper a special case of digital stochastic measurement of the third power of definite integral of sinusoidal signal’s absolute value, using 2-bit AD converters is presented. This case of digital stochastic method had emerged from the need to measure power and energy of the wind. Power and energy are proportional to the third power of wind speed. Anemometer output signal is sinusoidal. Therefore an integral of the third power of sinusoidal signal is zero. Two approaches are proposed for the third power calculation of the wind speed signal. One approach is to use absolute value of sinusoidal signal (before AD conversion for which there is no need of multiplier hardware change. The second approach requires small multiplier hardware change, but input signal remains unchanged. For the second approach proposed minimal hardware change was made to calculate absolute value of the result after AD conversion. Simulations have confirmed theoretical analysis. Expected precision of wind energy measurement of proposed device is better than 0,00051% of full scale. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR32019

  15. How accurately can videokeratographic systems measure surface elevation?

    Science.gov (United States)

    Applegate, R A; Nuñez, R; Buettner, J; Howland, H C

    1995-11-01

    Surface topography, as opposed to dioptric topography, defines the corneal surface in simple terms without assumptions. Accordingly, it is important to know how well surface topography can be measured with current videokeratometric machines. The purpose of this paper is to quantify the accuracy with which the TMS-1 Corneal Modeling System can measure the surface topography of calibrated spherical, elliptical, and bicurve surfaces. The Computed Anatomy TMS-1 videokeratometer was used to measure three spherical, three elliptical, and two bicurve surfaces with known characteristics. Surface characteristics were either back-calculated from the dioptric files or directly obtained from the TMS-1 elevation file for each of 6400 points (256 points in each of 25 rings). The accuracy with which each method determined the true surface was quantified by calculating the root mean squared error (RMSE) of the 6400 measured surface elevations from the known surface elevation at each sampling point. (1) For spherical and elliptical surfaces, back-calculation of surface elevation from the dioptric file can be made with RMSE of 5 mu or less. (2) For spheres but not elliptical surfaces the TMS-1 elevation file defines the surface with RMSE 5 mu or less. (3) The surface area measured by placido-based videokeratometers varies with surface curvature. (4) RMSE in measured surface elevation increase as the distance from the videokeratometric axis increases. (5) For bicurves, the dioptric maps are smoothed by the TMS-1 over abrupt transitions and for large transitions never recover. Additionally, our back-calculation methods further smooth abrupt transitions, making the RMSE of the bicurve surface that is back-calculated from the dioptric file larger than the RMSE of the surface generated from the TMS-1 elevation file. Surface elevations can be back-calculated from dioptric files with RMSE of 5 microns or less for spheres and elliptical surfaces as long as there are no areas of abrupt

  16. LHCb: A novel method for an absolute luminosity measurement at LHCb using beam-gas imaging

    CERN Multimedia

    Barschel, C

    2013-01-01

    A novel technique to measure the absolute luminosity at the Large Hadron Collider (LHC) using beam-gas interactions has been successfully used in the LHCb experiment. A gas injection device (SMOG) has been installed in the LHCb experiment to increase the pressure around the interaction point during dedicated fills. The Beam Gas Imaging method (BGI) has now the potential to surpass the accuracy of the commonly used van der Meer scan method (VDM). This poster presents the principles of the Beam Gas Imaging method used to measure the beam overlap integral. Furthermore the gas injection increased the accuracy measurement of the so-called ghost charges and also intensities per bunch.

  17. Absolute single photoionization cross-section measurements of Rb 2+ ions: experiment and theory

    Energy Technology Data Exchange (ETDEWEB)

    Macaluso, D. A. [Univ. of Montana, Missoula, MT (United States). Dept. of Physics and Astronomy; Bogolub, K. [Univ. of Montana, Missoula, MT (United States). Dept. of Physics and Astronomy; Johnson, A. [Univ. of Montana, Missoula, MT (United States). Dept. of Physics and Astronomy; Aguilar, A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Kilcoyne, A. L. D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Bilodeau, R. C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS); Univ. of Connecticut, Storrs, CT (United States). Dept. of Physics; Bautista, M. [Western Michigan Univ., Kalamazoo MI (United States). Dept. of Physics; Kerlin, A. B. [Univ. of West Georgia, Carrolton, GA (United States). Dept. of Physics; Sterling, N. C. [Univ. of West Georgia, Carrolton, GA (United States). Dept. of Physics

    2017-05-05

    Absolute single photoionization cross-section measurements of Rb 2+ ions were performed at the Advanced Light Source at Lawrence Berkeley National Laboratory using synchrotron radiation and the photo-ion, merged-beams technique. Measurements were made at a photon energy resolution of 13.5 2.5 meV from 37.31 to 44.08 eV spanning the 2 P ground state and 2 P metastable state ionization thresholds. Multiple autoionizing resonance series arising from each initial state are identified using quantum defect theory. The measurements are compared to Breit-Pauli R-matrix calculations with excellent agreement between theory and experiment.

  18. Absolute measurement of internal volume changes inside the pulse damper: discrepancy between delay and dwell volumes.

    Science.gov (United States)

    Rogatsky, Eduard; Zheng, Zheng; Stein, Daniel

    2010-06-01

    We have developed a novel technique for the absolute determination of the mobile phase volume stored inside of a variable volume pulse damper at different pressures. Using an Agilent HPLC pulse damper we found a linear volume increase of approximately 1 microL/bar. We found that pump pressurization is a relatively slow process and takes approximately 1 min to reach 90% and takes approximately 2 min to reach 99% equilibration at flow rates below 1 mL/min. During pump pressurization, column flow rate will be less than the pre-set, since part of the mobile phase is retained inside of the pulse damper. During our experiments we observed a discrepancy between data obtained by UV techniques and direct absolute measurements. This difference can be explained by a fundamental difference between the gradient delay volume and dead (dwell) volume.

  19. Characterization of Fricke-gel layers for absolute dose measurements in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G. [Dept. of Physics, ' Universita degli Studi' of Milan, via Celoria 16, I-20133 Milano (Italy); INFN Istituto Nazionale di Fisica Nucleare Section Milan, via Celoria 16, I-20133 Milano (Italy); Carrara, M. [Medical Physics Unit, Fondazione IRCCS Istituto Nazionale Tumori, Via Venezian 1, I-20133 Milano (Italy); Rrushi, B.; Guilizzoni, R. [Dept. of Physics, ' Universita degli Studi' of Milan, via Celoria 16, I-20133 Milano (Italy); Borroni, M.; Tomatis, S. [Medical Physics Unit, Fondazione IRCCS Istituto Nazionale Tumori, Via Venezian 1, I-20133 Milano (Italy); Pirola, L. [Dept. of Physics, ' Universita degli Studi' of Milan, via Celoria 16, I-20133 Milano (Italy); Battistoni, G. [INFN Istituto Nazionale di Fisica Nucleare Section Milan, via Celoria 16, I-20133 Milano (Italy)

    2011-07-01

    Fricke-gel layer dosimeters (FGLDs) have shown promising features for attaining absolute measurements of the spatial distribution of the absorbed dose in radiotherapy. Good precision of results (within 3%) is achieved by means of calibration of each single dosimeter before measurement. The calibration is performed irradiating the dosimeter at a uniform and precisely known dose, in order to get a calibration matrix that must be used, with pixel-to-pixel manipulation, to obtain the dose image. A study of the trend in time of dosimeter response after one or more exposures was carried out and calibration protocols were suitably established and verified. (authors)

  20. Measuring Absolute Thermospheric Densities And Accommodation Coefficients Using Paddlewheel Satellites: Past Findings, Present Uses, And Future Mission Concepts

    Science.gov (United States)

    Pilinski, Marcin D.; Moe, Kenneth; Palo, Scott E.; Argrow, Brian M.

    2011-07-01

    The first absolute measurement of thermospheric density was made by combining simultaneous observations of spin and semimajor axis decay of Explorer VI. Providing two independent measures of the interaction with the airstream enabled the determination of both air density and drag coefficient. Then by using a realistic model of the gas-surface interaction, the energy accommodation coefficient was determined. Only four such measurements were made prior to the time of writing. In this paper, we review the history of paddlewheel measurements and explain their importance to ongoing work in satellite drag. Next, a novel concept for paddlewheel satellites based on the CubeSat platform is discussed along with the relevant design parameters. A rudimentary error analysis for paddlewheel measurements evaluated the feasibility of these designs and it was found that the drag torques generated on a three-kilogram paddlewheel are within the measurement capabilities of today's technologies. For certain types of paddlewheel configurations, the use of direct simulation methods is important for accurately analyzing the data. This is because a paddlewheel with the spin axis oriented in the orbit normal direction undergoes significant flow-shadowing and this is not easily represented by analytical methods. Increasing the availability of accommodation measurements via the paddlewheel method represents an improvement in the accuracy of Earth's total density models as well as the understanding of gas-surface interactions in low Earth orbit. This is of profound importance in the prediction of satellite orbits as well as the understanding of atmospheric phenomena.

  1. Absolute measurement of the 242Pu neutron-capture cross section

    Science.gov (United States)

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; Bucher, B.; Chyzh, A.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Jandel, M.; Mosby, S.; O'Donnell, J. M.; Ullmann, J. L.; Dance Collaboration

    2016-04-01

    The absolute neutron-capture cross section of 242Pu was measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. The first direct measurement of the 242Pu(n ,γ ) cross section was made over the incident neutron energy range from thermal to ≈6 keV, and the absolute scale of the (n ,γ ) cross section was set according to the known 239Pu(n ,f ) resonance at En ,R=7.83 eV. This was accomplished by adding a small quantity of 239Pu to the 242Pu sample. The relative scale of the cross section, with a range of four orders of magnitude, was determined for incident neutron energies from thermal to ≈40 keV. Our data, in general, are in agreement with previous measurements and those reported in ENDF/B-VII.1; the 242Pu(n ,γ ) cross section at the En ,R=2.68 eV resonance is within 2.4 % of the evaluated value. However, discrepancies exist at higher energies; our data are ≈30 % lower than the evaluated data at En≈1 keV and are approximately 2 σ away from the previous measurement at En≈20 keV.

  2. Intercomparison of the LBIR Absolute Cryogenic Radiometers to the NIST Optical Power Measurement Standard.

    Science.gov (United States)

    Fedchak, James A; Carter, Adriaan C; Datla, Raju

    2006-01-01

    The Low Background Infrared calibration (LBIR) facility at the National Institute of Standards and Technology (NIST) presently maintains four absolute cryogenic radiometers (ACRs) which serve as standard reference detectors for infrared calibrations performed by the facility. The primary standard for optical power measurements at NIST-Gaithersburg has been the High Accuracy Cryogenic Radiometer (HACR). Recently, an improved radiometer, the Primary Optical Watt Radiometer (POWR), has replaced the HACR as the primary standard. In this paper, we present the results of comparisons between the radiometric powers measured by the four ACRs presently maintained by the LBIR facility to that measured by the HACR and POWR. This was done by using a Si photodiode light-trapping detector as a secondary transfer standard to compare the primary national standards to the ACRs maintained by the LBIR facility. The technique used to compare an ACR to the trap detector is described in detail. The absolute optical power measurements are found to be within 0.1 % of the primary standard for all the ACRs examined in this study.

  3. 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.

  4. Recent improvements of ISOLTRAP Absolute mass measurements of exotic nuclides at $10^{-8}$ precision

    CERN Document Server

    Kellerbauer, A G

    2003-01-01

    In the past three years, the sensitivity and the performance of the Penning trap mass spectrometer ISOLTRAP have been enhanced significantly. These improvements, which range from technical developments to systematic studies of the various factors contributing to the uncertainty of the final mass result, now allow mass measurements of short-lived radionuclides with half-lives of less than 100 ms and with a precision of better than 10$^{-8}$. Using a newly developed carbon cluster ion source, ISOLTRAP can perform absolute mass measurements relative to the microscopic mass standard $^{12}$C. These developments are reviewed as pertaining to the extension of ISOLTRAP mass measurements to higher precision and shorter half-lives and to molecular mass measurements.

  5. A Model for Converting Solid State Fermentation Growth Profiles Between Absolute and Relative Measurement Bases

    Directory of Open Access Journals (Sweden)

    Graciele Viccini

    2003-01-01

    Full Text Available A mathematical model is developed for converting between the two measurement bases commonly used in the construction of growth profiles in solid-state fermentation, namely absolute mass ratio m(dry biomass/m(initial dry matter and relative mass ratio m(dry biomass/m(dry matter. These are not equivalent, due to the loss of dry matter as CO2 during the fermentation. The model is equally applicable to any biomass component used in indirect measurements of growth, such as protein. Use of the model to convert absolute mass ratio of the biomass profiles for the growth of Rhizopus oligosporus to a relative basis gave profiles that agreed well with the experimentally determined relative biomass profiles. This agreement was obtained for three different fermentations using the same set of parameter values in the model, namely a yield coefficient of m(protein/m(dry substrate = 0.2 g/g and a maintenance coefficient of zero, giving confidence in the reliability of the model. The model was then used to show that the measurement basis used can affect the form of the curve and therefore can also affect the conclusion drawn about the type of kinetics shown by the organism, with the extent of this effect depending on the length of time that growth occurs and the values of the yield and maintenance coefficients. This work shows that great care must be taken in drawing conclusions about growth kinetics in solid-state fermentation.

  6. Absolute scale power measurements of frequency-locked coherent transition radiation

    Directory of Open Access Journals (Sweden)

    Roark A. Marsh

    2007-08-01

    Full Text Available We report the absolute power measurement of frequency-locked terahertz coherent transition radiation (CTR from a train of electron bunches produced by a 17.14 GHz accelerator. Frequency measurements were obtained by two independent techniques: a wave meter with a video diode detector, and a double heterodyne system. Good agreement was seen between these two techniques. The emitted radiation was observed to be a comb of frequencies that are harmonics of the 17.14 GHz accelerator frequency. The heterodyne receiver system showed that each of the emitted harmonics has a very narrow bandwidth, about 25 MHz, which corresponds to the transform-limited bandwidth for the bunch train length of 40 ns. The highest observed frequency was 377.08 GHz, the 22nd harmonic of the 17.14 GHz accelerator frequency. The emitted CTR power was measured on an absolute scale to test the theory of CTR. The power was compared with calculations made using an electric field integral equation (EFIE formulation and excellent agreement was obtained. This agreement serves as a valuable benchmark of the EFIE code, proof of both its validity and usefulness.

  7. The new IMGC-02 transportable absolute gravimeter: measurement apparatus and applications in geophysics and volcanology

    Directory of Open Access Journals (Sweden)

    V. D’errico

    2008-06-01

    Full Text Available The research carried out at the Istituto Nazionale di Ricerca Metrologica (formerly Istituto di Metrologia «G. Colonnetti» aiming to develop a transportable ballistic absolute gravimeter ended with a new version of the instrument, called the IMGC-02. It uses laser interferometry to measure the symmetrical free rising and falling motion of a test mass in the gravity field. Providing the same accuracy achieved with previous versions, the instrumental improvements mainly concern size, weight, data processing algorithms and operational simplicity. An uncertainty of 9 ?Gal (1 ?Gal=1×10–8 m·s?2 can be achieved within a single observation session, lasting about 12 h, while the time series of several observation sessions show a reproducibility of 4 ?Gal. At this level, gravity measurements provide useful information in Geophysics and Volcanology. A wide set of dynamic phenomena, i.e. seismicity and volcanic activity, can produce temporal gravity changes, often quite small, with an amplitude ranging from a few to hundreds of microgals. Therefore the IMGC absolute gravimeter has been employed since 1986 in surveying the Italian active volcanoes. A brief history of the gravimeter and the description of the new apparatus, together with the main results of ongoing applications in Geophysics and Volcanology are presented.

  8. Microfabricated Collector-Generator Electrode Sensor for Measuring Absolute pH and Oxygen Concentrations.

    Science.gov (United States)

    Dengler, Adam K; Wightman, R Mark; McCarty, Gregory S

    2015-10-20

    Fast-scan cyclic voltammetry (FSCV) has attracted attention for studying in vivo neurotransmission due to its subsecond temporal resolution, selectivity, and sensitivity. Traditional FSCV measurements use background subtraction to isolate changes in the local electrochemical environment, providing detailed information on fluctuations in the concentration of electroactive species. This background subtraction removes information about constant or slowly changing concentrations. However, determination of background concentrations is still important for understanding functioning brain tissue. For example, neural activity is known to consume oxygen and produce carbon dioxide which affects local levels of oxygen and pH. Here, we present a microfabricated microelectrode array which uses FSCV to detect the absolute levels of oxygen and pH in vitro. The sensor is a collector-generator electrode array with carbon microelectrodes spaced 5 μm apart. In this work, a periodic potential step is applied at the generator producing transient local changes in the electrochemical environment. The collector electrode continuously performs FSCV enabling these induced changes in concentration to be recorded with the sensitivity and selectivity of FSCV. A negative potential step applied at the generator produces a transient local pH shift at the collector. The generator-induced pH signal is detected using FSCV at the collector and correlated to absolute solution pH by postcalibration of the anodic peak position. In addition, in oxygenated solutions a negative potential step at the generator produces hydrogen peroxide by reducing oxygen. Hydrogen peroxide is detected with FSCV at the collector electrode, and the magnitude of the oxidative peak is proportional to absolute oxygen concentrations. Oxygen interference on the pH signal is minimal and can be accounted for with a postcalibration.

  9. Absolute choline concentration measured by quantitative proton MR spectroscopy correlates with cell density in meningioma

    Energy Technology Data Exchange (ETDEWEB)

    Yue, Qiang [University of Tsukuba, Department of Neurosurgery, Institute of Clinical Medicine, Tsukuba Science City, Ibaraki (Japan)]|[West China Hospital of Sichuan University, Huaxi MR Research Center, Department of Radiology, Chengdu (China); Shibata, Yasushi; Kawamura, Hiraku; Matsumura, Akira [University of Tsukuba, Department of Neurosurgery, Institute of Clinical Medicine, Tsukuba Science City, Ibaraki (Japan); Isobe, Tomonori [Kitasato University, Department of Medical Technology, School of Allied Health Sciences, Minato, Tokyo (Japan); Anno, Izumi [University of Tsukuba, Department of Radiology, Institute of Clinical Medicine, Tsukuba, Ibaraki (Japan); Gong, Qi-Yong [West China Hospital of Sichuan University, Huaxi MR Research Center, Department of Radiology, Chengdu (China)]|[University of Liverpool, Division of Medical Imaging, Faculty of Medicine, Liverpool (United Kingdom)

    2009-01-15

    This study was aimed to investigate the relationship between quantitative proton magnetic resonance spectroscopy (1H-MRS) and pathological changes in meningioma. Twenty-two meningioma cases underwent single voxel 1H-MRS (point-resolved spectroscopy sequence, repetition time/echo time = 2,000 ms/68, 136, 272 ms). Absolute choline (Cho) concentration was calculated using tissue water as the internal reference and corrected according to intra-voxel cystic/necrotic parts. Pathological specimens were stained with MIB-1 antibody to measure cell density and proliferation index. Correlation analysis was performed between absolute Cho concentration and cell density and MIB-1 labeled proliferation index. Average Cho concentration of all meningiomas before correction was 2.95 {+-} 0.86 mmol/kg wet weight. It was increased to 3.23 {+-} 1.15 mmol/kg wet weight after correction. Average cell density of all meningiomas was 333 {+-} 119 cells/HPF, and average proliferation index was 2.93 {+-} 5.72%. A linear, positive correlation between cell density and Cho concentration was observed (r = 0.650, P = 0.001). After correction of Cho concentration, the correlation became more significant (r = 0.737, P < 0.001). However, no significant correlation between Cho concentration and proliferation index was found. There seemed to be a positive correlation trend after correction of Cho concentration but did not reach significant level. Absolute Cho concentration, especially Cho concentration corrected according to intra-voxel cystic/necrotic parts, reflects cell density of meningioma. (orig.)

  10. The magnetic recoil spectrometer for measurements of the absolute neutron spectrum at OMEGA and the NIF.

    Science.gov (United States)

    Casey, D T; Frenje, J A; Johnson, M Gatu; Séguin, F H; Li, C K; Petrasso, R D; Glebov, V Yu; Katz, J; Magoon, J; Meyerhofer, D D; Sangster, T C; Shoup, M; Ulreich, J; Ashabranner, R C; Bionta, R M; Carpenter, A C; Felker, B; Khater, H Y; LePape, S; MacKinnon, A; McKernan, M A; Moran, M; Rygg, J R; Yeoman, M F; Zacharias, R; Leeper, R J; Fletcher, K; Farrell, M; Jasion, D; Kilkenny, J; Paguio, R

    2013-04-01

    The neutron spectrum produced by deuterium-tritium (DT) inertial confinement fusion implosions contains a wealth of information about implosion performance including the DT yield, ion-temperature, and areal-density. The Magnetic Recoil Spectrometer (MRS) has been used at both the OMEGA laser facility and the National Ignition Facility (NIF) to measure the absolute neutron spectrum from 3 to 30 MeV at OMEGA and 3 to 36 MeV at the NIF. These measurements have been used to diagnose the performance of cryogenic target implosions to unprecedented accuracy. Interpretation of MRS data requires a detailed understanding of the MRS response and background. This paper describes ab initio characterization of the system involving Monte Carlo simulations of the MRS response in addition to the commission experiments for in situ calibration of the systems on OMEGA and the NIF.

  11. Measurement of the absolute branching fraction for Λc+→Λμ+νμ

    Directory of Open Access Journals (Sweden)

    M. Ablikim

    2017-04-01

    Full Text Available We report the first measurement of the absolute branching fraction for Λc+→Λμ+νμ. This measurement is based on a sample of e+e− annihilation data produced at a center-of-mass energy s=4.6 GeV, collected with the BESIII detector at the BEPCII storage rings. The sample corresponds to an integrated luminosity of 567 pb−1. The branching fraction is determined to be B(Λc+→Λμ+νμ=(3.49±0.46(stat±0.27(syst%. In addition, we calculate the ratio B(Λc+→Λμ+νμ/B(Λc+→Λe+νe to be 0.96±0.16(stat±0.04(syst.

  12. Measurement of the Absolute Branching Fraction for Λ_{c}^{+}→Λe^{+}ν_{e}.

    Science.gov (United States)

    Ablikim, M; Achasov, M N; Ai, X C; Albayrak, O; Albrecht, M; Ambrose, D J; Amoroso, A; An, F F; An, Q; Bai, J Z; Baldini Ferroli, R; Ban, Y; Bennett, D W; Bennett, J V; Bertani, M; Bettoni, D; Bian, J M; Bianchi, F; Boger, E; Boyko, I; Briere, R A; Cai, H; Cai, X; Cakir, O; Calcaterra, A; Cao, G F; Cetin, S A; Chang, J F; Chelkov, G; Chen, G; Chen, H S; Chen, H Y; Chen, J C; Chen, M L; Chen, S J; Chen, X; Chen, X R; Chen, Y B; Cheng, H P; Chu, X K; Cibinetto, G; Dai, H L; Dai, J P; Dbeyssi, A; Dedovich, D; Deng, Z Y; Denig, A; Denysenko, I; Destefanis, M; De Mori, F; Ding, Y; Dong, C; Dong, J; Dong, L Y; Dong, M Y; Dou, Z L; Du, S X; Duan, P F; Fan, J Z; Fang, J; Fang, S S; Fang, X; Fang, Y; Fava, L; Fedorov, O; Feldbauer, F; Felici, G; Feng, C Q; Fioravanti, E; Fritsch, M; Fu, C D; Gao, Q; Gao, X L; Gao, X Y; Gao, Y; Gao, Z; Garzia, I; Goetzen, K; Gong, W X; Gradl, W; Greco, M; Gu, M H; Gu, Y T; Guan, Y H; Guo, A Q; Guo, L B; Guo, Y; Guo, Y P; Haddadi, Z; Hafner, A; Han, S; Hao, X Q; Harris, F A; He, K L; Held, T; Heng, Y K; Hou, Z L; Hu, C; Hu, H M; Hu, J F; Hu, T; Hu, Y; Huang, G M; Huang, G S; Huang, J S; Huang, X T; Huang, Y; Hussain, T; Ji, Q; Ji, Q P; Ji, X B; Ji, X L; Jiang, L W; Jiang, X S; Jiang, X Y; Jiao, J B; Jiao, Z; Jin, D P; Jin, S; Johansson, T; Julin, A; Kalantar-Nayestanaki, N; Kang, X L; Kang, X S; Kavatsyuk, M; Ke, B C; Kiese, P; Kliemt, R; Kloss, B; Kolcu, O B; Kopf, B; Kornicer, M; Kuehn, W; Kupsc, A; Lange, J S; Lara, M; Larin, P; Leng, C; Li, C; Li, Cheng; Li, D M; Li, F; Li, F Y; Li, G; Li, H B; Li, J C; Li, Jin; Li, K; Li, K; Li, Lei; Li, P R; Li, T; Li, W D; Li, W G; Li, X L; Li, X M; Li, X N; Li, X Q; Li, Z B; Liang, H; Liang, Y F; Liang, Y T; Liao, G R; Lin, D X; Liu, B J; Liu, C X; Liu, D; Liu, F H; Liu, Fang; Liu, Feng; Liu, H B; Liu, H H; Liu, H H; Liu, H M; Liu, J; Liu, J B; Liu, J P; Liu, J Y; Liu, K; Liu, K Y; Liu, L D; Liu, P L; Liu, Q; Liu, S B; Liu, X; Liu, Y B; Liu, Z A; Liu, Zhiqing; Lou, X C; Lu, H J; Lu, J G; Lu, Y; Lu, Y P; Luo, C L; Luo, M X; Luo, T; Luo, X L; Lyu, X R; Ma, F C; Ma, H L; Ma, L L; Ma, Q M; Ma, T; Ma, X N; Ma, X Y; Maas, F E; Maggiora, M; Mao, Y J; Mao, Z P; Marcello, S; Messchendorp, J G; Min, J; Mitchell, R E; Mo, X H; Mo, Y J; Morales Morales, C; Muchnoi, N Yu; Muramatsu, H; Nefedov, Y; Nerling, F; Nikolaev, I B; Ning, Z; Nisar, S; Niu, S L; Niu, X Y; Olsen, S L; Ouyang, Q; Pacetti, S; Pan, Y; Patteri, P; Pelizaeus, M; Peng, H P; Peters, K; Pettersson, J; Ping, J L; Ping, R G; Poling, R; Prasad, V; Qi, H R; Qi, M; Qian, S; Qiao, C F; Qin, L Q; Qin, N; Qin, X S; Qin, Z H; Qiu, J F; Rashid, K H; Redmer, C F; Ripka, M; Rong, G; Rosner, Ch; Ruan, X D; Santoro, V; Sarantsev, A; Savrié, M; Schoenning, K; Schumann, S; Shan, W; Shao, M; Shen, C P; Shen, P X; Shen, X Y; Sheng, H Y; Song, W M; Song, X Y; Sosio, S; Spataro, S; Sun, G X; Sun, J F; Sun, S S; Sun, Y J; Sun, Y Z; Sun, Z J; Sun, Z T; Tang, C J; Tang, X; Tapan, I; Thorndike, E H; Tiemens, M; Ullrich, M; Uman, I; Varner, G S; Wang, B; Wang, B L; Wang, D; Wang, D Y; Wang, K; Wang, L L; Wang, L S; Wang, M; Wang, P; Wang, P L; Wang, S G; Wang, W; Wang, W P; Wang, X F; Wang, Y D; Wang, Y F; Wang, Y Q; Wang, Z; Wang, Z G; Wang, Z H; Wang, Z Y; Weber, T; Wei, D H; Wei, J B; Weidenkaff, P; Wen, S P; Wiedner, U; Wolke, M; Wu, L H; Wu, Z; Xia, L; Xia, L G; Xia, Y; Xiao, D; Xiao, H; Xiao, Z J; Xie, Y G; Xiu, Q L; Xu, G F; Xu, L; Xu, Q J; Xu, Q N; Xu, X P; Yan, L; Yan, W B; Yan, W C; Yan, Y H; Yang, H J; Yang, H X; Yang, L; Yang, Y; Yang, Y X; Ye, M; Ye, M H; Yin, J H; Yu, B X; Yu, C X; Yu, J S; Yuan, C Z; Yuan, W L; Yuan, Y; Yuncu, A; Zafar, A A; Zallo, A; Zeng, Y; Zeng, Z; Zhang, B X; Zhang, B Y; Zhang, C; Zhang, C C; Zhang, D H; Zhang, H H; Zhang, H Y; Zhang, J J; Zhang, J L; Zhang, J Q; Zhang, J W; Zhang, J Y; Zhang, J Z; Zhang, K; Zhang, L; Zhang, X Y; Zhang, Y; Zhang, Y H; Zhang, Y N; Zhang, Y T; Zhang, Yu; Zhang, Z H; Zhang, Z P; Zhang, Z Y; Zhao, G; Zhao, J W; Zhao, J Y; Zhao, J Z; Zhao, Lei; Zhao, Ling; Zhao, M G; Zhao, Q; Zhao, Q W; Zhao, S J; Zhao, T C; Zhao, Y B; Zhao, Z G; Zhemchugov, A; Zheng, B; Zheng, J P; Zheng, W J; Zheng, Y H; Zhong, B; Zhou, L; Zhou, X; Zhou, X K; Zhou, X R; Zhou, X Y; Zhu, K; Zhu, K J; Zhu, S; Zhu, S H; Zhu, X L; Zhu, Y C; Zhu, Y S; Zhu, Z A; Zhuang, J; Zotti, L; Zou, B S; Zou, J H

    2015-11-27

    We report the first measurement of the absolute branching fraction for Λ_{c}^{+}→Λe^{+}ν_{e}. This measurement is based on 567  pb^{-1} of e^{+}e^{-} annihilation data produced at sqrt[s]=4.599  GeV, which is just above the Λ_{c}^{+}Λ[over ¯]_{c}^{-} threshold. The data were collected with the BESIII detector at the BEPCII storage rings. The branching fraction is determined to be B(Λ_{c}^{+}→Λe^{+}ν_{e})=[3.63±0.38(stat)±0.20(syst)]%, representing a significant improvement in precision over the current indirect determination. As the branching fraction for Λ_{c}^{+}→Λe^{+}ν_{e} is the benchmark for those of other Λ_{c}^{+} semileptonic channels, our result provides a unique test of different theoretical models, which is the most stringent to date.

  13. The magnetic recoil spectrometer for measurements of the absolute neutron spectrum at OMEGA and the NIF

    Energy Technology Data Exchange (ETDEWEB)

    Casey, D. T.; Frenje, J. A.; Gatu Johnson, M.; Seguin, F. H.; Li, C. K.; Petrasso, R. D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Glebov, V. Yu.; Katz, J.; Magoon, J.; Meyerhofer, D. D.; Sangster, T. C.; Shoup, M.; Ulreich, J. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Ashabranner, R. C.; Bionta, R. M.; Carpenter, A. C.; Felker, B.; Khater, H. Y.; LePape, S.; MacKinnon, A. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); and others

    2013-04-15

    The neutron spectrum produced by deuterium-tritium (DT) inertial confinement fusion implosions contains a wealth of information about implosion performance including the DT yield, ion-temperature, and areal-density. The Magnetic Recoil Spectrometer (MRS) has been used at both the OMEGA laser facility and the National Ignition Facility (NIF) to measure the absolute neutron spectrum from 3 to 30 MeV at OMEGA and 3 to 36 MeV at the NIF. These measurements have been used to diagnose the performance of cryogenic target implosions to unprecedented accuracy. Interpretation of MRS data requires a detailed understanding of the MRS response and background. This paper describes ab initio characterization of the system involving Monte Carlo simulations of the MRS response in addition to the commission experiments for in situ calibration of the systems on OMEGA and the NIF.

  14. Absolute alpha activity measurements of some plants growing in monazite bearing soils in Sri Lanka

    Energy Technology Data Exchange (ETDEWEB)

    Mahawatte, P.; Hewamanna, R. (Colombo Univ. (Sri Lanka). Radioisotope Centre)

    1991-01-01

    Deposits of monazite bearing soils occur along the Southwest, West and East Coasts of Sri Lanka. High levels of gamma activity in some plant species growing in the West Coast have been reported. The high levels were due to the presence of the daughter nuclides of {sup 232}Th, most of which are alpha emitters. Absolute alpha activity measurements of ash samples of some plants growing in monazite bearing soils were carried out using the alpha sensitive polymeric nuclear track detector CR-39. The values ranged from 60-1900 mBq/g and were in good agreement with the values obtained from conventional scintillation counting method. The activity concentration of {sup 228}Th in the ash samples was also calculated by measuring the activity concentration of emanated thoron trapped inside a glass bottle with the use of a CR-39 track detector. (author).

  15. Optical parameters Determination for absolute luminosity and total cross section measurements in ATLAS

    CERN Document Server

    Cavalier, Sophie

    ALFA (Absolute Luminosity For ATLAS) aims at measuring the absolute luminosity for the ATLAS experiment with an incertitude down to 2-3 \\% and the total elastic cross section. The luminosity is related to the number of events, the highest the luminosity, the highest the number of events. This is, then, an important quantity for colliders like LHC (Large Hadron Collider). LHC is made of two beams circulating in two different beam pipes and colliding at four interaction points where the four physics experiments are located (ATLAS, CMS, ALICE, LHCb). ALFA detectors inserted into Roman Pots (RPs), have been placed around ATLAS at 240 m distance from the collision point (IP1) after six quadrupoles magnets and two dipoles defining the ALFA beam line which is part of the LHC ring.The detectors are made of scintillating optics fibers to catch elastic protons generated at IP1. These protons are tracked through the LHC magnets beam line which needs to be optimized in terms of optics parameters. We call high β optics, ...

  16. A new method for the absolute radiance calibration for UV-vis measurements of scattered sunlight

    Science.gov (United States)

    Wagner, T.; Beirle, S.; Dörner, S.; Penning de Vries, M.; Remmers, J.; Rozanov, A.; Shaiganfar, R.

    2015-10-01

    Absolute radiometric calibrations are important for measurements of the atmospheric spectral radiance. Such measurements can be used to determine actinic fluxes, the properties of aerosols and clouds, and the shortwave energy budget. Conventional calibration methods in the laboratory are based on calibrated light sources and reflectors and are expensive, time consuming and subject to relatively large uncertainties. Also, the calibrated instruments might change during transport from the laboratory to the measurement sites. Here we present a new calibration method for UV-vis instruments that measure the spectrally resolved sky radiance, for example zenith sky differential optical absorption spectroscopy (DOAS) instruments or multi-axis (MAX)-DOAS instruments. Our method is based on the comparison of the solar zenith angle dependence of the measured zenith sky radiance with radiative transfer simulations. For the application of our method, clear-sky measurements during periods with almost constant aerosol optical depth are needed. The radiative transfer simulations have to take polarisation into account. We show that the calibration results are almost independent from the knowledge of the aerosol optical properties and surface albedo, which causes a rather small uncertainty of about ozone column density during the measurements be constant and known.

  17. 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

  18. Accurate micro Hall effect measurements on scribe line pads

    DEFF Research Database (Denmark)

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

    2009-01-01

    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...... 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...

  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...... status, and addresses future challenges for spherical near-field antenna measurements; in particular, from the viewpoint of the DTU-ESA Spherical Near-Field Antenna Test Facility....

  20. Advancing Absolute Calibration for JWST and Other Applications

    Science.gov (United States)

    Rieke, George; Bohlin, Ralph; Boyajian, Tabetha; Carey, Sean; Casagrande, Luca; Deustua, Susana; Gordon, Karl; Kraemer, Kathleen; Marengo, Massimo; Schlawin, Everett; Su, Kate; Sloan, Greg; Volk, Kevin

    2017-10-01

    We propose to exploit the unique optical stability of the Spitzer telescope, along with that of IRAC, to (1) transfer the accurate absolute calibration obtained with MSX on very bright stars directly to two reference stars within the dynamic range of the JWST imagers (and of other modern instrumentation); (2) establish a second accurate absolute calibration based on the absolutely calibrated spectrum of the sun, transferred onto the astronomical system via alpha Cen A; and (3) provide accurate infrared measurements for the 11 (of 15) highest priority stars with no such data but with accurate interferometrically measured diameters, allowing us to optimize determinations of effective temperatures using the infrared flux method and thus to extend the accurate absolute calibration spectrally. This program is integral to plans for an accurate absolute calibration of JWST and will also provide a valuable Spitzer legacy.

  1. Problems with Accurate Atomic Lfetime Measurements of Multiply Charged Ions

    Energy Technology Data Exchange (ETDEWEB)

    Trabert, E

    2009-02-19

    A number of recent atomic lifetime measurements on multiply charged ions have reported uncertainties lower than 1%. Such a level of accuracy challenges theory, which is a good thing. However, a few lessons learned from earlier precision lifetime measurements on atoms and singly charged ions suggest to remain cautious about the systematic errors of experimental techniques.

  2. 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.

  3. Integration of Absolute Orientation Measurements in the KinectFusion Reconstruction pipeline

    KAUST Repository

    Giancola, Silvio

    2018-02-12

    In this paper, we show how absolute orientation measurements provided by low-cost but high-fidelity IMU sensors can be integrated into the KinectFusion pipeline. We show that integration improves both runtime, robustness and quality of the 3D reconstruction. In particular, we use this orientation data to seed and regularize the ICP registration technique. We also present a technique to filter the pairs of 3D matched points based on the distribution of their distances. This filter is implemented efficiently on the GPU. Estimating the distribution of the distances helps control the number of iterations necessary for the convergence of the ICP algorithm. Finally, we show experimental results that highlight improvements in robustness, a speed-up of almost 12%, and a gain in tracking quality of 53% for the ATE metric on the Freiburg benchmark.

  4. Absolute equation of state measurements up to a gigbar using a converging shock

    Science.gov (United States)

    Kostinski, Natalie; Swift, Damian; Kritcher, Andrea; Lazicki, Amy; Hawreliak, James; Doeppner, Tilo; Saunders, Alison; Bachmann, Benjamin; Collins, Gilbert; Falcone, Roger; Nilsen, Joseph

    2017-10-01

    We are developing laser-driven loading platforms that allow the equation of state (EOS) of matter to be measured to pressures above 10 TPa on the Omega laser and 80 TPa at the National Ignition Facility respectively. These pressures are reached using a spherically-converging shock, with x-ray radiography as the primary diagnostic, enabling absolute EOS measurements to be made. At pressures above 10 TPa, the x-ray opacity drops significantly because of k-shell ionization. Superficially, this would prevent the compression from being measured, but radiographic marker layers can be used to constrain the reconstructed object and enable the opacity and compression to be determined simultaneously. Using these techniques, we have measured the Hugoniot EOS of polystyrene, diamond, and boron to over 50 TPa respectively, enabling their use as reference materials for relative measurements of materials more opaque to x-rays. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  5. 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.

  6. An absolute index (Ab-index to measure a researcher's useful contributions and productivity.

    Directory of Open Access Journals (Sweden)

    Akshaya Kumar Biswal

    Full Text Available Bibliographic analysis has been a very powerful tool in evaluating the effective contributions of a researcher and determining his/her future research potential. The lack of an absolute quantification of the author's scientific contributions by the existing measurement system hampers the decision-making process. In this paper, a new metric system, Absolute index (Ab-index, has been proposed that allows a more objective comparison of the contributions of a researcher. The Ab-index takes into account the impact of research findings while keeping in mind the physical and intellectual contributions of the author(s in accomplishing the task. The Ab-index and h-index were calculated for 10 highly cited geneticists and molecular biologist and 10 young researchers of biological sciences and compared for their relationship to the researchers input as a primary author. This is the first report of a measuring method clarifying the contributions of the first author, corresponding author, and other co-authors and the sharing of credit in a logical ratio. A java application has been developed for the easy calculation of the Ab-index. It can be used as a yardstick for comparing the credibility of different scientists competing for the same resources while the Productivity index (Pr-index, which is the rate of change in the Ab-index per year, can be used for comparing scientists of different age groups. The Ab-index has clear advantage over other popular metric systems in comparing scientific credibility of young scientists. The sum of the Ab-indices earned by individual researchers of an institute per year can be referred to as Pr-index of the institute.

  7. 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

  8. 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 radiat...... radiation. The paper describes how such measurements are carried out as well as a suitable experimental set-up. The main reflector of the European Space Agency's MIMR system is used to demonstrate the principle...

  9. Visual texture accurate material appearance measurement, representation and modeling

    CERN Document Server

    Haindl, Michal

    2013-01-01

    This book surveys the state of the art in multidimensional, physically-correct visual texture modeling. Features: reviews the entire process of texture synthesis, including material appearance representation, measurement, analysis, compression, modeling, editing, visualization, and perceptual evaluation; explains the derivation of the most common representations of visual texture, discussing their properties, advantages, and limitations; describes a range of techniques for the measurement of visual texture, including BRDF, SVBRDF, BTF and BSSRDF; investigates the visualization of textural info

  10. 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.

  11. Gain Instabilities in Photomultipliers: How Accurate are Photon Counting Measurements?

    Science.gov (United States)

    Rosen, W. A.; Chromey, F. R.

    1984-01-01

    Experiments performed on five commercially available photomultiplier tubes indicate that gain instabilities can be an important source of error in photon counting measurements at the 1% level. It is shown that the error cannot be significantly reduced by standard differential measurement techniques. Analysis of time variations in the pulse height distribution is shown to be a sensitive diagnostic tool for the measurement of gain variations. Using this technique it is found that gain variations occur at counting rates as low as 100 Hz. It is argued that such errors will be present at some level in all tubes. Several calibrating schemes capable of reducing the error to below the 0.1% level are discussed.

  12. Measurements of Absolute Hadronic Branching Fractions of the Λ_{c}^{+} Baryon.

    Science.gov (United States)

    Ablikim, M; Achasov, M N; Ai, X C; Albayrak, O; Albrecht, M; Ambrose, D J; Amoroso, A; An, F F; An, Q; Bai, J Z; Baldini Ferroli, R; Ban, Y; Bennett, D W; Bennett, J V; Bertani, M; Bettoni, D; Bian, J M; Bianchi, F; Boger, E; Boyko, I; Briere, R A; Cai, H; Cai, X; Cakir, O; Calcaterra, A; Cao, G F; Cetin, S A; Chang, J F; Chelkov, G; Chen, G; Chen, H S; Chen, H Y; Chen, J C; Chen, M L; Chen, S J; Chen, X; Chen, X R; Chen, Y B; Cheng, H P; Chu, X K; Cibinetto, G; Dai, H L; Dai, J P; Dbeyssi, A; Dedovich, D; Deng, Z Y; Denig, A; Denysenko, I; Destefanis, M; De Mori, F; Ding, Y; Dong, C; Dong, J; Dong, L Y; Dong, M Y; Dou, Z L; Du, S X; Duan, P F; Eren, E E; Fan, J Z; Fang, J; Fang, S S; Fang, X; Fang, Y; Farinelli, R; Fava, L; Fedorov, O; Feldbauer, F; Felici, G; Feng, C Q; Fioravanti, E; Fritsch, M; Fu, C D; Gao, Q; Gao, X L; Gao, X Y; Gao, Y; Gao, Z; Garzia, I; Goetzen, K; Gong, L; Gong, W X; Gradl, W; Greco, M; Gu, M H; Gu, Y T; Guan, Y H; Guo, A Q; Guo, L B; Guo, Y; Guo, Y P; Haddadi, Z; Hafner, A; Han, S; Hao, X Q; Harris, F A; He, K L; Held, T; Heng, Y K; Hou, Z L; Hu, C; Hu, H M; Hu, J F; Hu, T; Hu, Y; Huang, G S; Huang, J S; Huang, X T; Huang, Y; Hussain, T; Ji, Q; Ji, Q P; Ji, X B; Ji, X L; Jiang, L W; Jiang, X S; Jiang, X Y; Jiao, J B; Jiao, Z; Jin, D P; Jin, S; Johansson, T; Julin, A; Kalantar-Nayestanaki, N; Kang, X L; Kang, X S; Kavatsyuk, M; Ke, B C; Kiese, P; Kliemt, R; Kloss, B; Kolcu, O B; Kopf, B; Kornicer, M; Kuehn, W; Kupsc, A; Lange, J S; Lara, M; Larin, P; Leng, C; Li, C; Li, Cheng; Li, D M; Li, F; Li, F Y; Li, G; Li, H B; Li, J C; Li, Jin; Li, K; Li, K; Li, Lei; Li, P R; Li, Q Y; Li, T; Li, W D; Li, W G; Li, X L; Li, X M; Li, X N; Li, X Q; Li, Z B; Liang, H; Liang, Y F; Liang, Y T; Liao, G R; Lin, D X; Liu, B J; Liu, C X; Liu, D; Liu, F H; Liu, Fang; Liu, Feng; Liu, H B; Liu, H H; Liu, H H; Liu, H M; Liu, J; Liu, J B; Liu, J P; Liu, J Y; Liu, K; Liu, K Y; Liu, L D; Liu, P L; Liu, Q; Liu, S B; Liu, X; Liu, Y B; Liu, Z A; Liu, Zhiqing; Loehner, H; Lou, X C; Lu, H J; Lu, J G; Lu, Y; Lu, Y P; Luo, C L; Luo, M X; Luo, T; Luo, X L; Lyu, X R; Ma, F C; Ma, H L; Ma, L L; Ma, Q M; Ma, T; Ma, X N; Ma, X Y; Ma, Y M; Maas, F E; Maggiora, M; Mao, Y J; Mao, Z P; Marcello, S; Messchendorp, J G; Min, J; Mitchell, R E; Mo, X H; Mo, Y J; Morales Morales, C; Muchnoi, N Yu; Muramatsu, H; Nefedov, Y; Nerling, F; Nikolaev, I B; Ning, Z; Nisar, S; Niu, S L; Niu, X Y; Olsen, S L; Ouyang, Q; Pacetti, S; Pan, Y; Patteri, P; Pelizaeus, M; Peng, H P; Peters, K; Pettersson, J; Ping, J L; Ping, R G; Poling, R; Prasad, V; Qi, H R; Qi, M; Qian, S; Qiao, C F; Qin, L Q; Qin, N; Qin, X S; Qin, Z H; Qiu, J F; Rashid, K H; Redmer, C F; Ripka, M; Rong, G; Rosner, Ch; Ruan, X D; Santoro, V; Sarantsev, A; Savrié, M; Schoenning, K; Schumann, S; Shan, W; Shao, M; Shen, C P; Shen, P X; Shen, X Y; Sheng, H Y; Song, W M; Song, X Y; Sosio, S; Spataro, S; Sun, G X; Sun, J F; Sun, S S; Sun, Y J; Sun, Y Z; Sun, Z J; Sun, Z T; Tang, C J; Tang, X; Tapan, I; Thorndike, E H; Tiemens, M; Ullrich, M; Uman, I; Varner, G S; Wang, B; Wang, B L; Wang, D; Wang, D Y; Wang, K; Wang, L L; Wang, L S; Wang, M; Wang, P; Wang, P L; Wang, S G; Wang, W; Wang, W P; Wang, X F; Wang, Y D; Wang, Y F; Wang, Y Q; Wang, Z; Wang, Z G; Wang, Z H; Wang, Z Y; Weber, T; Wei, D H; Wei, J B; Weidenkaff, P; Wen, S P; Wiedner, U; Wolke, M; Wu, L H; Wu, Z; Xia, L; Xia, L G; Xia, Y; Xiao, D; Xiao, H; Xiao, Z J; Xie, Y G; Xiu, Q L; Xu, G F; Xu, L; Xu, Q J; Xu, Q N; Xu, X P; Yan, L; Yan, W B; Yan, W C; Yan, Y H; Yang, H J; Yang, H X; Yang, L; Yang, Y X; Ye, M; Ye, M H; Yin, J H; Yu, B X; Yu, C X; Yu, J S; Yuan, C Z; Yuan, W L; Yuan, Y; Yuncu, A; Zafar, A A; Zallo, A; Zeng, Y; Zeng, Z; Zhang, B X; Zhang, B Y; Zhang, C; Zhang, C C; Zhang, D H; Zhang, H H; Zhang, H Y; Zhang, J J; Zhang, J L; Zhang, J Q; Zhang, J W; Zhang, J Y; Zhang, J Z; Zhang, K; Zhang, L; Zhang, X Y; Zhang, Y; Zhang, Y H; Zhang, Y N; Zhang, Y T; Zhang, Yu; Zhang, Z H; Zhang, Z P; Zhang, Z Y; Zhao, G; Zhao, J W; Zhao, J Y; Zhao, J Z; Zhao, Lei; Zhao, Ling; Zhao, M G; Zhao, Q; Zhao, Q W; Zhao, S J; Zhao, T C; Zhao, Y B; Zhao, Z G; Zhemchugov, A; Zheng, B; Zheng, J P; Zheng, W J; Zheng, Y H; Zhong, B; Zhou, L; Zhou, X; Zhou, X K; Zhou, X R; Zhou, X Y; Zhu, K; Zhu, K J; Zhu, S; Zhu, S H; Zhu, X L; Zhu, Y C; Zhu, Y S; Zhu, Z A; Zhuang, J; Zotti, L; Zou, B S; Zou, J H

    2016-02-05

    We report the first measurement of absolute hadronic branching fractions of Λ_{c}^{+} baryon at the Λ_{c}^{+}Λ[over ¯]_{c}^{-} production threshold, in the 30 years since the Λ_{c}^{+} discovery. In total, 12 Cabibbo-favored Λ_{c}^{+} hadronic decay modes are analyzed with a double-tag technique, based on a sample of 567  pb^{-1} of e^{+}e^{-} collisions at sqrt[s]=4.599  GeV recorded with the BESIII detector. A global least-squares fitter is utilized to improve the measured precision. Among the measurements for twelve Λ_{c}^{+} decay modes, the branching fraction for Λ_{c}^{+}→pK^{-}π^{+} is determined to be (5.84±0.27±0.23)%, where the first uncertainty is statistical and the second is systematic. In addition, the measurements of the branching fractions of the other 11 Cabibbo-favored hadronic decay modes are significantly improved.

  13. On the measurement of relative and absolute income-related health inequality.

    Science.gov (United States)

    Clarke, Philip M; Gerdtham, Ulf-G; Johannesson, Magnus; Bingefors, Kerstin; Smith, Len

    2002-12-01

    In recent work on international comparisons of income-related inequalities in health, the concentration index has been used as a measure of health inequality. A drawback of this measure is that it is sensitive to whether it is estimated with respect to health or morbidity. An alternative would be to use the generalized concentration index that is based on absolute rather than relative health differences. In this methodological paper, we explore the importance of the choice of health inequality measure by comparing the income-related inequality in health status and morbidity between Sweden and Australia. This involves estimating a concentration index and a generalized concentration index for the eight-scale health profile of the Short Form 36 (SF-36) health survey. We then transform the scores for each scale into a measure of morbidity and show that whether the concentration index is estimated with respect to health or morbidity has an impact on the results. The ranking between the two countries is reversed for two of the eight dimensions of SF-36 and within both countries the ranking across the eight SF-36 scales is also affected. However, this change in ranking does not occur when the generalized concentration index is compared and we conclude with the implications of these results for reporting comparisons of income-related health inequality in different populations.

  14. A new method for the absolute measurement of piezoelectric coefficients on thin polymer films

    Science.gov (United States)

    Guillot; Jarzynski

    2000-08-01

    A new quasistatic method to measure piezoelectric coefficients on thin polymer films is presented. This method is based on a combined experimental/analytical approach, where small polymer samples (6 mm x 3 mm x 110 microm) are encapsulated in a soft silicone rubber and an electric field is applied across their thickness (3-direction). Strains are measured optically along three perpendicular directions using a laser Doppler vibrometer, and the experimental measurements are used in a Rayleigh-Ritz energy minimization procedure implemented symbolically in MATHCAD, which yields the absolute piezoelectric coefficients d(3ii). These measured coefficients are material properties of the polymer and do not depend on the specific boundary conditions of the problem. The validity of the method is established using the ATILA finite element code. Experimental values of d(311), d(322), and d(333) obtained for polyvinylidene fluoride (PVDF) at room temperature, in the frequency range 500-2000 Hz, are presented and compared with existing data; excellent agreement is found. The extension of the method to the determination of electrostrictive coefficients on soft polyurethane materials is introduced.

  15. 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.

  16. 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.

  17. 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.

  18. ACCUWIND - Accurate wind speed measurements in wind energy - Summary report

    DEFF Research Database (Denmark)

    Friis Pedersen, Troels; Dahlberg, J.-Å.; Cuerva, A.

    2006-01-01

    The cup anemometer is at present the standard instrument used for mean wind speed measurement in wind energy. It is being applied in high numbers around the world for wind energy assessments. It is also applied exclusively for accredited power performancemeasurements for certification...

  19. ACCURATE TEMPERATURE MEASUREMENTS IN A NATURALLY-ASPIRATED RADIATION SHIELD

    Energy Technology Data Exchange (ETDEWEB)

    Kurzeja, R.

    2009-09-09

    Experiments and calculations were conducted with a 0.13 mm fine wire thermocouple within a naturally-aspirated Gill radiation shield to assess and improve the accuracy of air temperature measurements without the use of mechanical aspiration, wind speed or radiation measurements. It was found that this thermocouple measured the air temperature with root-mean-square errors of 0.35 K within the Gill shield without correction. A linear temperature correction was evaluated based on the difference between the interior plate and thermocouple temperatures. This correction was found to be relatively insensitive to shield design and yielded an error of 0.16 K for combined day and night observations. The correction was reliable in the daytime when the wind speed usually exceeds 1 m s{sup -1} but occasionally performed poorly at night during very light winds. Inspection of the standard deviation in the thermocouple wire temperature identified these periods but did not unambiguously locate the most serious events. However, estimates of sensor accuracy during these periods is complicated by the much larger sampling volume of the mechanically-aspirated sensor compared with the naturally-aspirated sensor and the presence of significant near surface temperature gradients. The root-mean-square errors therefore are upper limits to the aspiration error since they include intrinsic sensor differences and intermittent volume sampling differences.

  20. Cryogenic Current Comparator for Absolute Measurement of the Dark Current of the Superconducting Cavities for Tesla

    CERN Document Server

    Knaack, K; Wittenburg, K

    2003-01-01

    A newly high performance SQUID based measurement system for detecting dark currents, generated by superconducting cavities for TESLA is proposed. It makes use of the Cryogenic Current Comparator principle and senses dark currents in the nA range with a small signal bandwidth of 70 kHz. To reach the maximum possible energy in the TESLA project is a strong motivation to push the gradients of the superconducting cavities closer to the physical limit of 50 MV/m. The field emission of electrons (the so called dark current) of the superconducting cavities at strong fields may limit the maximum gradient. The absolute measurement of the dark current in correlation with the gradient will give a proper value to compare and classify the cavities. This contribution describes a Cryogenic Current Comparator (CCC) as an excellent and useful tool for this purpose. The most important component of the CCC is a high performance DC SQUID system which is able to measure extremely low magnetic fields, e.g. caused by the extracted ...

  1. Luminosity measurement method for the LHC: Event selection and absolute luminosity determination

    Science.gov (United States)

    Krasny, M. W.; Chwastowski, J.; Cyz, A.; Słowikowski, K.

    2013-11-01

    In our earlier papers Krasny et al. [1,2] have proposed a new luminosity measurement method which uses lepton pairs produced in peripheral collisions of the LHC beam particles, and identified the requirements for a new, specialized luminosity detector which is indispensable for their efficient on-line selection. In this paper we use the base-line detector model, with no precise timing capabilities, to evaluate the statistical and systematic accuracy of the method. We propose the complete event selection procedure and demonstrate that it allows to collect a sufficiently large sample of e+e- pairs to achieve a better than 1% statistical accuracy of the luminosity measurement over less than one-month-long running time intervals. We argue that the absolute luminosity measurement systematic errors can be kept below 1%. The proposed method can be directly applied to the LHC running periods for which the machine instantaneous luminosity does not exceed the L=1033 s-1 cm-2 value. Two ways extending the method to the large pile-up periods corresponding to higher instantaneous luminosities are proposed.

  2. Absolute brightness modeling for improved measurement of electron temperature from soft x-rays on MST

    Science.gov (United States)

    Reusch, L. M.; Franz, P.; Goetz, J. A.; den Hartog, D. J.; Nornberg, M. D.; van Meter, P.

    2017-10-01

    The two-color soft x-ray tomography (SXT) diagnostic on MST is now capable of Te measurement down to 500 eV. The previous lower limit was 1 keV, due to the presence of SXR emission lines from Al sputtered from the MST wall. The two-color technique uses two filters of different thickness to form a coarse spectrometer to estimate the slope of the continuum x-ray spectrum, which depends on Te. The 1.6 - 2.0 keV Al emission lines were previously filtered out by using thick Be filters (400 µm and 800 µm), thus restricting the range of the SXT diagnostic to Te >= 1 keV. Absolute brightness modeling explicitly includes several sources of radiation in the analysis model, enabling the use of thinner filters and measurement of much lower Te. Models based on the atomic database and analysis structure (ADAS) agree very well with our experimental SXR measurements. We used ADAS to assess the effect of bremsstrahlung, recombination, dielectronic recombination, and line emission on the inferred Te. This assessment informed the choice of the optimum filter pair to extend the Te range of the SXT diagnostic. This material is based upon work supported by the U.S. Department of Energy Office of Science, Office of Fusion Energy Sciences program under Award Numbers DE-FC02-05ER54814 and DE-SC0015474.

  3. An approach for the accurate measurement of social morality levels.

    Science.gov (United States)

    Liu, Haiyan; Chen, Xia; Zhang, Bo

    2013-01-01

    In the social sciences, computer-based modeling has become an increasingly important tool receiving widespread attention. However, the derivation of the quantitative relationships linking individual moral behavior and social morality levels, so as to provide a useful basis for social policy-making, remains a challenge in the scholarly literature today. A quantitative measurement of morality from the perspective of complexity science constitutes an innovative attempt. Based on the NetLogo platform, this article examines the effect of various factors on social morality levels, using agents modeling moral behavior, immoral behavior, and a range of environmental social resources. Threshold values for the various parameters are obtained through sensitivity analysis; and practical solutions are proposed for reversing declines in social morality levels. The results show that: (1) Population size may accelerate or impede the speed with which immoral behavior comes to determine the overall level of social morality, but it has no effect on the level of social morality itself; (2) The impact of rewards and punishment on social morality levels follows the "5∶1 rewards-to-punishment rule," which is to say that 5 units of rewards have the same effect as 1 unit of punishment; (3) The abundance of public resources is inversely related to the level of social morality; (4) When the cost of population mobility reaches 10% of the total energy level, immoral behavior begins to be suppressed (i.e. the 1/10 moral cost rule). The research approach and methods presented in this paper successfully address the difficulties involved in measuring social morality levels, and promise extensive application potentials.

  4. An approach for the accurate measurement of social morality levels.

    Directory of Open Access Journals (Sweden)

    Haiyan Liu

    Full Text Available In the social sciences, computer-based modeling has become an increasingly important tool receiving widespread attention. However, the derivation of the quantitative relationships linking individual moral behavior and social morality levels, so as to provide a useful basis for social policy-making, remains a challenge in the scholarly literature today. A quantitative measurement of morality from the perspective of complexity science constitutes an innovative attempt. Based on the NetLogo platform, this article examines the effect of various factors on social morality levels, using agents modeling moral behavior, immoral behavior, and a range of environmental social resources. Threshold values for the various parameters are obtained through sensitivity analysis; and practical solutions are proposed for reversing declines in social morality levels. The results show that: (1 Population size may accelerate or impede the speed with which immoral behavior comes to determine the overall level of social morality, but it has no effect on the level of social morality itself; (2 The impact of rewards and punishment on social morality levels follows the "5∶1 rewards-to-punishment rule," which is to say that 5 units of rewards have the same effect as 1 unit of punishment; (3 The abundance of public resources is inversely related to the level of social morality; (4 When the cost of population mobility reaches 10% of the total energy level, immoral behavior begins to be suppressed (i.e. the 1/10 moral cost rule. The research approach and methods presented in this paper successfully address the difficulties involved in measuring social morality levels, and promise extensive application potentials.

  5. An Approach for the Accurate Measurement of Social Morality Levels

    Science.gov (United States)

    Liu, Haiyan; Chen, Xia; Zhang, Bo

    2013-01-01

    In the social sciences, computer-based modeling has become an increasingly important tool receiving widespread attention. However, the derivation of the quantitative relationships linking individual moral behavior and social morality levels, so as to provide a useful basis for social policy-making, remains a challenge in the scholarly literature today. A quantitative measurement of morality from the perspective of complexity science constitutes an innovative attempt. Based on the NetLogo platform, this article examines the effect of various factors on social morality levels, using agents modeling moral behavior, immoral behavior, and a range of environmental social resources. Threshold values for the various parameters are obtained through sensitivity analysis; and practical solutions are proposed for reversing declines in social morality levels. The results show that: (1) Population size may accelerate or impede the speed with which immoral behavior comes to determine the overall level of social morality, but it has no effect on the level of social morality itself; (2) The impact of rewards and punishment on social morality levels follows the “5∶1 rewards-to-punishment rule,” which is to say that 5 units of rewards have the same effect as 1 unit of punishment; (3) The abundance of public resources is inversely related to the level of social morality; (4) When the cost of population mobility reaches 10% of the total energy level, immoral behavior begins to be suppressed (i.e. the 1/10 moral cost rule). The research approach and methods presented in this paper successfully address the difficulties involved in measuring social morality levels, and promise extensive application potentials. PMID:24312189

  6. Accurate Measurement of Magnetic Resonance Imaging Gradient Characteristics

    Directory of Open Access Journals (Sweden)

    Hui Liu

    2013-12-01

    Full Text Available Recently, gradient performance and fidelity has become of increasing interest, as the fidelity of the magnetic resonance (MR image is somewhat dependent on the fidelity of the gradient system. In particular, for high fidelity non-Cartesian imaging, due to non-fidelity of the gradient system, it becomes necessary to know the actual k-space trajectory as opposed to the requested trajectory. In this work we show that, by considering the gradient system as a linear time-invariant system, the gradient impulse response function (GIRF can be reliably measured to a relatively high degree of accuracy with a simple setup, using a small phantom and a series of simple experiments. It is shown experimentally that the resulting GIRF is able to predict actual gradient performance with a high degree of accuracy. The method captures not only the frequency response but also gradient timing errors and artifacts due to mechanical vibrations of the gradient system. Some discussion is provided comparing the method presented here with other analogous methods, along with limitations of these methods.

  7. In-Flight Measurement of the Absolute Energy Scale of the Fermi Large Area Telescope

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, M.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Ajello, M.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Allafort, A.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Atwood, W.B.; /UC, Santa Cruz; Axelsson, M.; /Stockholm U. /Stockholm U., OKC /Royal Inst. Tech., Stockholm; Baldini, L.; /INFN, Pisa; Barbiellini, G.; /INFN, Trieste /Trieste U.; Bastieri, D.; /INFN, Padua /Padua U.; Bechtol, K.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bellazzini, R.; /INFN, Pisa; Berenji, B.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bloom, E.D.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bonamente, E.; /INFN, Perugia /Perugia U.; Borgland, A.W.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Bouvier, A.; /UC, Santa Cruz; Bregeon, J.; /INFN, Pisa; Brez, A.; /INFN, Pisa; Brigida, M.; /Bari Polytechnic /INFN, Bari; Bruel, P.; /Ecole Polytechnique; Buehler, R.; /Stanford U., HEPL /SLAC /KIPAC, Menlo Park; Buson, S.; /INFN, Padua /Padua U. /CSIC, Catalunya /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /IASF, Milan /DAPNIA, Saclay /INFN, Perugia /Perugia U. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Unlisted, US /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /ASDC, Frascati /Perugia U. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Montpellier U. /ASDC, Frascati /Bari Polytechnic /INFN, Bari /Naval Research Lab, Wash., D.C. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Montpellier U. /Bari Polytechnic /INFN, Bari /Ecole Polytechnique /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Ecole Polytechnique /Hiroshima U. /Stanford U., HEPL /SLAC /KIPAC, Menlo Park /Bari Polytechnic /INFN, Bari /INFN, Bari /NASA, Goddard /INFN, Perugia /Perugia U.; /more authors..

    2012-09-20

    The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope is a pair-conversion telescope designed to survey the gamma-ray sky from 20 MeV to several hundreds of GeV. In this energy band there are no astronomical sources with sufficiently well known and sharp spectral features to allow an absolute calibration of the LAT energy scale. However, the geomagnetic cutoff in the cosmic ray electron-plus-positron (CRE) spectrum in low Earth orbit does provide such a spectral feature. The energy and spectral shape of this cutoff can be calculated with the aid of a numerical code tracing charged particles in the Earth's magnetic field. By comparing the cutoff value with that measured by the LAT in different geomagnetic positions, we have obtained several calibration points between {approx}6 and {approx}13 GeV with an estimated uncertainty of {approx}2%. An energy calibration with such high accuracy reduces the systematic uncertainty in LAT measurements of, for example, the spectral cutoff in the emission from gamma ray pulsars.

  8. The Compact Lightweight Absolute Radiometer (CLARA) for Total Solar Irradiance Measurements on the NORSAT-1 Satellite

    Science.gov (United States)

    Walter, Benjamin; Finsterle, Wolfgang; Koller, Silvio; Levesque, Pierre-Luc; Pfiffner, Daniel; Schmutz, Werner

    2017-04-01

    Continuous and precise Total Solar Irradiance (TSI) measurements are indispensable to evaluate the influence of short- and long-term solar variability on the Earth's energy budget. The existence of a potential long-term trend in the suns activity and whether or not such a trend could be climate effective is still a matter of debate. The Compact Lightweight Absolute Radiometer (CLARA) is one of PMOD/WRC's future contributions to the almost seamless series of space borne TSI measurements since 1978. CLARA was designed and built by PMOD/WRC and characterized and calibrated by PMOD/WRC as part of the "European Metrology Research Program" (EMRP) project "European Metrology for Earth Observation and Climate" (MetEOC-2) funded by the European Commission. The main goals of the CLARA experiment are to continue the TSI data record with high accuracy and precision and to facilitate monitoring with its compact and adaptable design. CLARA will be one of three payloads of the Norwegian micro satellite NORSAT-1, along with Langmuir probes for space plasma research and an Automatic Identification System (AIS) receiver to monitor maritime traffic in Norwegian waters. The launch of NORSAT-1 is planned for March 2017. We present the design and calibration of CLARA, a new generation of Electrical Substitution Radiometers (ESR) comprising the latest radiometer developments of PMOD/WRC: i) A three-detector design for degradation tracking and redundancy, ii) a digital control system, iii) a new reference block and detector design to minimize size and weight of the instrument. The characterization of the CLARA instrument components provides an overview on the improvements that were achieved with the latest radiometer developments. An end-to-end calibration of CLARA against the SI-traceable cryogenic radiometer of the TSI Radiometer Facility (TRF) at the Laboratory for Atmospheric and Space Physics (LASP) in Boulder (Colorado) results in a combined measurement uncertainty of 0.05% (k = 1

  9. Absolute coronary blood flow measurement and microvascular resistance in ST-elevation myocardial infarction in the acute and subacute phase

    Energy Technology Data Exchange (ETDEWEB)

    Wijnbergen, Inge; Veer, Marcel van ' t [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven (Netherlands); Lammers, Jeroen; Ubachs, Joey [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Pijls, Nico H.J., E-mail: nico.pijls@cze.nl [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven (Netherlands)

    2016-03-15

    Background/Purpose: In a number of patients with acute myocardial infarction (AMI), myocardial hypoperfusion, known as the no-reflow phenomenon, persists after primary percutaneous intervention (PPCI). The aim of this study was to evaluate the feasibility and safety of a new quantitative method of measuring absolute blood flow and resistance within the perfusion bed of an infarct-related artery. Furthermore, we sought to study no-reflow by correlating these measurements to the index of microvascular resistance (IMR) and the area at risk (AR) as determined by cardiac magnetic resonance imaging (CMR). Methods: Measurements of absolute flow and myocardial resistance were performed in 20 patients with ST-segment elevation myocardial infarction (STEMI), first immediately following PPCI and then again after 3–5 days. These measurements used the technique of thermodilution during a continuous infusion of saline. Flow was expressed in ml/min per gram of tissue within the area at risk. Results: The average time needed for measurement of absolute flow, resistance and IMR was 20 min, and all measurements could be performed without complication. A higher flow supplying the AR correlated with a lower IMR in the acute phase. Absolute flow increased from 3.14 to 3.68 ml/min/g (p = 0.25) and absolute resistance decreased from 1317 to 1099 dyne.sec.cm-5/g (p = 0.40) between the first day and fifth day after STEMI. Conclusions: Measurement of absolute flow and microvascular resistance is safe and feasible in STEMI patients and may allow for a better understanding of microvascular (dys)function in the early phase of AMI. - Highlights: • We measured absolute coronary blood flow and microvascular resistance in STEMI patients in the acute phase and in the subacute phase, using the technique of thermodilution with low grade intracoronary continuous infusion of saline. • These measurements are safe and feasible during PPCI in STEMI patients. • In STEMI patients, absolute flow

  10. Frontal cortex absolute beta power measurement in Panic Disorder with Agoraphobia patients.

    Science.gov (United States)

    de Carvalho, Marcele Regine; Velasques, Bruna Brandão; Freire, Rafael C; Cagy, Maurício; Marques, Juliana Bittencourt; Teixeira, Silmar; Thomaz, Rafael; Rangé, Bernard P; Piedade, Roberto; Akiskal, Hagop Souren; Nardi, Antonio Egidio; Ribeiro, Pedro

    2015-09-15

    Panic disorder patients are hypervigilant to danger cues and highly sensitive to unpredictable aversive events, what leads to anticipatory anxiety, that is one key component of the disorder maintenance. Prefrontal cortex seems to be involved in these processes and beta band activity may be related to the involvement of top-down processing, whose function is supposed to be disrupted in pathological anxiety. The objective of this study was to measure frontal absolute beta-power (ABP) with qEEG in panic disorder and agoraphobia (PDA) patients compared to healthy controls. qEEG data were acquired while participants (24 PDA patients and 21 controls) watched a computer simulation (CS), consisting of moments classified as "high anxiety" (HAM) and "low anxiety" (LAM). qEEG data were also acquired during two rest conditions, before and after the computer simulation display. The statistical analysis was performed by means of a repeated measure analysis of variance (two-way ANOVA) and ABP was the dependent variable of interest. The main hypothesis was that a higher ABP in PDA patients would be found related to controls. Moreover, in HAM the ABP would be different than in LAM. the main finding was an interaction between the moment and group for the electrodes F7, F8, Fp1 and Fp2. We observed a higher ABP in PDA patients when compared to controls while watching the CS. The higher beta-power in the frontal cortex for the PDA group may reflect a state of high excitability, together with anticipatory anxiety and maintenance of hypervigilant cognitive state. our results suggest a possible deficiency in top-down processing reflected by a higher ABP in the PDA group while watching the CS and they highlight the recruitment of prefrontal regions during the exposure to anxiogenic stimuli. the small sample, the wide age range of participants and the use of psychotropic medications by most of the PDA patients. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Reduced dose measurement of absolute myocardial blood flow using dynamic SPECT imaging in a porcine model

    Energy Technology Data Exchange (ETDEWEB)

    Timmins, Rachel; Klein, Ran; Petryk, Julia; Marvin, Brian; Kemp, Robert A. de; Ruddy, Terrence D.; Wells, R. Glenn, E-mail: gwells@ottawaheart.ca [Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario K1Y4W7 (Canada); Wei, Lihui [Nordion, Inc., Ottawa, Ontario K2K 1X8 (Canada)

    2015-09-15

    Purpose: Absolute myocardial blood flow (MBF) and myocardial flow reserve (MFR) measurements provide important additional information over traditional relative perfusion imaging. Recent advances in camera technology have made this possible with single-photon emission tomography (SPECT). Low dose protocols are desirable to reduce the patient radiation risk; however, increased noise may reduce the accuracy of MBF measurements. The authors studied the effect of reducing dose on the accuracy of dynamic SPECT MBF measurements. Methods: Nineteen 30–40 kg pigs were injected with 370 + 1110 MBq of Tc-99m sestamibi or tetrofosmin or 37 + 111 MBq of Tl-201 at rest + stress. Microspheres were injected simultaneously to measure MBF. The pigs were imaged in list-mode for 11 min starting at the time of injection using a Discovery NM 530c camera (GE Healthcare). Each list file was modified so that 3/4, 1/2, 1/4, 1/8, 1/16, and 1/32 of the original counts were included in the projections. Modified projections were reconstructed with CT-based attenuation correction and an energy window-based scatter correction and analyzed with FlowQuant kinetic modeling software using a 1-compartment model. A modified Renkin-Crone extraction function was used to convert the tracer uptake rate K1 to MBF values. The SPECT results were compared to those from microspheres. Results: Correlation between SPECT and microsphere MBF values for the full injected activity was r ≥ 0.75 for all 3 tracers and did not significantly degrade over all count levels. The mean MBF and MFR and the standard errors in the estimates were not significantly worse than the full-count data at 1/4-counts (Tc99m-tracers) and 1/2-counts (Tl-201). Conclusions: Dynamic SPECT measurement of MBF and MFR in pigs can be performed with 1/4 (Tc99m-tracers) or 1/2 (Tl-201) of the standard injected activity without significantly reducing accuracy and precision.

  12. Reduced Haemodynamic Response in the Ageing Visual Cortex Measured by Absolute fNIRS.

    Directory of Open Access Journals (Sweden)

    Laura McKernan Ward

    Full Text Available The effect of healthy ageing on visual cortical activation is still to be fully explored. This study aimed to elucidate whether the haemodynamic response (HDR of the visual cortex altered as a result of ageing. Visually normal (healthy participants were presented with a simple visual stimulus (reversing checkerboard. Full optometric screening was implemented to identify two age groups: younger adults (n = 12, mean age 21 and older adults (n = 13, mean age 71. Frequency-domain Multi-distance (FD-MD functional Near-Infrared Spectroscopy (fNIRS was used to measure absolute changes in oxygenated [HbO] and deoxygenated [HbR] haemoglobin concentrations in the occipital cortices. Utilising a slow event-related design, subjects viewed a full field reversing checkerboard with contrast and check size manipulations (15 and 30 minutes of arc, 50% and 100% contrast. Both groups showed the characteristic response of increased [HbO] and decreased [HbR] during stimulus presentation. However, older adults produced a more varied HDR and often had comparable levels of [HbO] and [HbR] during both stimulus presentation and baseline resting state. Younger adults had significantly greater concentrations of both [HbO] and [HbR] in every investigation regardless of the type of stimulus displayed (p<0.05. The average variance associated with this age-related effect for [HbO] was 88% and [HbR] 91%. Passive viewing of a visual stimulus, without any cognitive input, showed a marked age-related decline in the cortical HDR. Moreover, regardless of stimulus parameters such as check size, the HDR was characterised by age. In concurrence with present neuroimaging literature, we conclude that the visual HDR decreases as healthy ageing proceeds.

  13. Absolute multilateration between spheres

    Science.gov (United States)

    Muelaner, Jody; Wadsworth, William; Azini, Maria; Mullineux, Glen; Hughes, Ben; Reichold, Armin

    2017-04-01

    Environmental effects typically limit the accuracy of large scale coordinate measurements in applications such as aircraft production and particle accelerator alignment. This paper presents an initial design for a novel measurement technique with analysis and simulation showing that that it could overcome the environmental limitations to provide a step change in large scale coordinate measurement accuracy. Referred to as absolute multilateration between spheres (AMS), it involves using absolute distance interferometry to directly measure the distances between pairs of plain steel spheres. A large portion of each sphere remains accessible as a reference datum, while the laser path can be shielded from environmental disturbances. As a single scale bar this can provide accurate scale information to be used for instrument verification or network measurement scaling. Since spheres can be simultaneously measured from multiple directions, it also allows highly accurate multilateration-based coordinate measurements to act as a large scale datum structure for localized measurements, or to be integrated within assembly tooling, coordinate measurement machines or robotic machinery. Analysis and simulation show that AMS can be self-aligned to achieve a theoretical combined standard uncertainty for the independent uncertainties of an individual 1 m scale bar of approximately 0.49 µm. It is also shown that combined with a 1 µm m-1 standard uncertainty in the central reference system this could result in coordinate standard uncertainty magnitudes of 42 µm over a slender 1 m by 20 m network. This would be a sufficient step change in accuracy to enable next generation aerospace structures with natural laminar flow and part-to-part interchangeability.

  14. Operational principle, testing, and applications of the AWID-flat jack for absolute stress determinations using voltage measurements

    Science.gov (United States)

    Kessels, W.

    1986-07-01

    Stress measurements can be performed with the, measuring principle for a flat jack discussed in this paper without any material parameters of the flat jack being of influence. This means that no calibration measurements are required by this flat jack for absolute measurements and there is no dependence on temperature. It is called “Absolut Widerstands Druckmesskissen” or short AWID-Flat Jack. Basis of evaluation is a change in the electrical resistivity of the flat jack, which is caused by two metal sheets separating from each other when inflated with hydraulic oil as soon as the external pressure is reached. Besides theoretical considerations concerning the mode of operation of the flat jack, this paper presents laboratory measurements performed in an autoclave as well as in a tube filled with salt grit under a uniaxial press. Changes of stress can be measured if the flat jack is cemented into a borehole under initial stress. The absolute stress of the bedrock can be measured after a certain time of adjustment in rock capable of creep (salt, clay, etc.). The advantages of the AWID measuring system are confirmed by in situ-measurements in a salt pillar loadable with variable pressure. In a temperature experiment at the Asse salt mine (Federal Republic of Germany) where the salt was heated up to 200°C, the advantages of the AWID measurement system were confirmed.

  15. DETERMINATION OF THE ABSOLUTE EXCITED-STATE DENSITY OF A SODIUM TARGET BY MEANS OF BEAM DEFLECTION MEASUREMENTS

    NARCIS (Netherlands)

    WIERSEMA, WP; SCHLATMANN, AR; MORGENSTERN, R

    1994-01-01

    The average deflection of a laser excited, divergent sodium beam with a broad velocity distribution is measured by means of a Langmuir-Taylor detector and exploited for determining the absolute density of the excited state in the interaction area. Simulations of the excitation and deflection process

  16. Absolute navigation for Mars final approach using relative measurements of X-ray pulsars and Mars orbiter

    Science.gov (United States)

    Wang, Shuo; Cui, Pingyuan; Gao, Ai; Yu, Zhengshi; Cao, Menglong

    2017-09-01

    To achieve a precise Mars landing, the autonomous navigation performance of Mars final approach phase need to be further improved. In this paper, an absolute navigation scheme for Mars finial approach phase using relative measurements of X-ray pulsars and Mars orbiter is proposed. By introducing the difference of time of arrival (DTOA) measurement, the states of approach spacecraft and orbiter are estimated at the same time. Compared to the navigation scheme based on the absolute measurements of pulsars, the error sources such as planetary ephemeris error, pulsar parameter uncertainties, and radio beacon position deviations, are correspondingly reduced or eliminated. Through observability analysis, the method of absolute navigation using relative information is proved observable under the condition of reasonable pulsars selection. The design optimization of beacon configuration based on the Fisher Information Matrix (FIM) is also carried out for achieving a better observability. Two navigation schemes respectively based on the absolute/relative measurements of X-ray pulsars are compared by numerical simulations, and the navigation performance is assessed and the feasibility of the proposed scheme is verified.

  17. Measurement of Absolute Hydroxyl Radical Concentration in Lean Fuel-Air Mixtures Excited by Nanosecond Pulsed Discharge.

    Science.gov (United States)

    Yin, Z.; Lempert, W. R.; Adamovich, I. V.

    2013-06-01

    The focus in plasma assisted combustion research has been on the evaluation of conventional plasma/combustion mechanisms in predicting oxidation and ignition processes initiated and/or sustained by non-equilibrium, nanosecond discharges. Accurate quantitative data such as temperature and species concentration are needed for assessing and improving numerical modeling. As an important intermediate species, the concentration of hydroxyl radical (OH) is very sensitive to the combustion environment (e.g., temperature, equivalence ratio), and therefore is of great interest to kinetic study. In this work, Laser-Induced Fluorescence (LIF) was used for time-resolved temperature and OH number density measurements in lean H_2-, CH_4-, C_2H_4-, and C_3H_8- air mixtures in a plasma flow reactor inside a tube furnace. The premixed fuel-air flow in the reactor, initially at T_0=500 K and P=100 torr, was excited by a burst of repetitive nanosecond electric pulses in a dielectric-barrier plane-to-plane geometry (˜28 kV peak voltage and ˜5 nsec pulse width, estimated 1.25 mJ/pulse coupled energy). Laser was timed to probe after the discharge burst was over to avoid strong plasma emission interference. Relative fluorescence signal was put on an absolute scale by calibrating against Rayleigh scattering signal in the same flow reactor. Experimental results were compared to predictions from a 0-D plasma/combustion chemistry model employing several well-established combustion mechanisms. 2-D temperature and OH concentration distributions in the discharge volume were obtained by planar LIF and was used to quantitatively evaluate plasma uniformity in the reactor. These results were used to determine the validity of the 0-D model. thanks

  18. Measurement of the Absolute Proton and Helium Flux at the Top of the Atmosphere using IMAX

    DEFF Research Database (Denmark)

    Menn, W.; Hof, M.; Reimer, O.

    1996-01-01

    with ancillary scintillators, time-of-flight, and aerogel cherenkov detectors. High resolution drift chambers and MWPCs were used as the tracking devices. Using redundant detectors, an extensive examination of the instrument efficiency was carried out. We present the absolute spectra of protons and helium...

  19. Using relative and absolute measures for monitoring health inequalities: experiences from cross-national analyses on maternal and child health

    Directory of Open Access Journals (Sweden)

    Huisman Martijn

    2007-10-01

    Full Text Available Abstract Background As reducing socio-economic inequalities in health is an important public health objective, monitoring of these inequalities is an important public health task. The specific inequality measure used can influence the conclusions drawn, and there is no consensus on which measure is most meaningful. The key issue raising most debate is whether to use relative or absolute inequality measures. Our paper aims to inform this debate and develop recommendations for monitoring health inequalities on the basis of empirical analyses for a broad range of developing countries. Methods Wealth-group specific data on under-5 mortality, immunisation coverage, antenatal and delivery care for 43 countries were obtained from the Demographic and Health Surveys. These data were used to describe the association between the overall level of these outcomes on the one hand, and relative and absolute poor-rich inequalities in these outcomes on the other. Results We demonstrate that the values that the absolute and relative inequality measures can take are bound by mathematical ceilings. Yet, even where these ceilings do not play a role, the magnitude of inequality is correlated with the overall level of the outcome. The observed tendencies are, however, not necessities. There are countries with low mortality levels and low relative inequalities. Also absolute inequalities showed variation at most overall levels. Conclusion Our study shows that both absolute and relative inequality measures can be meaningful for monitoring inequalities, provided that the overall level of the outcome is taken into account. Suggestions are given on how to do this. In addition, our paper presents data that can be used for benchmarking of inequalities in the field of maternal and child health in low and middle-income countries.

  20. Accurate calculation of the absolute free energy of binding for drug molecules† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c5sc02678d Click here for additional data file.

    Science.gov (United States)

    Aldeghi, Matteo; Heifetz, Alexander; Bodkin, Michael J.; Knapp, Stefan

    2016-01-01

    Accurate prediction of binding affinities has been a central goal of computational chemistry for decades, yet remains elusive. Despite good progress, the required accuracy for use in a drug-discovery context has not been consistently achieved for drug-like molecules. Here, we perform absolute free energy calculations based on a thermodynamic cycle for a set of diverse inhibitors binding to bromodomain-containing protein 4 (BRD4) and demonstrate that a mean absolute error of 0.6 kcal mol–1 can be achieved. We also show a similar level of accuracy (1.0 kcal mol–1) can be achieved in pseudo prospective approach. Bromodomains are epigenetic mark readers that recognize acetylation motifs and regulate gene transcription, and are currently being investigated as therapeutic targets for cancer and inflammation. The unprecedented accuracy offers the exciting prospect that the binding free energy of drug-like compounds can be predicted for pharmacologically relevant targets. PMID:26798447

  1. Measuring Absolute RNA Copy Numbers at High Temporal Resolution Reveals Transcriptome Kinetics in Development

    Directory of Open Access Journals (Sweden)

    Nick D.L. Owens

    2016-01-01

    Full Text Available Transcript regulation is essential for cell function, and misregulation can lead to disease. Despite technologies to survey the transcriptome, we lack a comprehensive understanding of transcript kinetics, which limits quantitative biology. This is an acute challenge in embryonic development, where rapid changes in gene expression dictate cell fate decisions. By ultra-high-frequency sampling of Xenopus embryos and absolute normalization of sequence reads, we present smooth gene expression trajectories in absolute transcript numbers. During a developmental period approximating the first 8 weeks of human gestation, transcript kinetics vary by eight orders of magnitude. Ordering genes by expression dynamics, we find that “temporal synexpression” predicts common gene function. Remarkably, a single parameter, the characteristic timescale, can classify transcript kinetics globally and distinguish genes regulating development from those involved in cellular metabolism. Overall, our analysis provides unprecedented insight into the reorganization of maternal and embryonic transcripts and redefines our ability to perform quantitative biology.

  2. Absolute measurement of D-T neutron flux with a monitor using activation of flowing water

    Energy Technology Data Exchange (ETDEWEB)

    Uno, Y. E-mail: uno@cens.tokai.jaeri.go.jp; Kaneko, J.; Nishitani, T.; Maekawa, F.; Tanaka, T.; Shibata, S.; Ikeda, Y.; Khripunov, V.; Walker, C.; Ebisawa, K.; Takeuchi, H

    2001-10-01

    Neutron activation with water flow based on the {sup 16}O(n, p){sup 16}N reaction (T{sub 1/2}=7.13 s) has been proposed for the accurate fusion power monitor with reasonable time resolution in International Thermonuclear Experimental Reactor (ITER)-FEAT. The experiment for validation of the method for determining the neutron flux was carried out at the Fusion Neutronics Source (FNS) facility in Japan Atomic Energy Research Institute (JAERI). The stainless steel (SS316)/Water assembly was utilized to simulate a neutron field in the blanket region of ITER. The closed water loop was laid between the assembly and the shielded measurement area. The {gamma}-rays from the irradiated water were measured by Bi{sub 4}Ge{sub 3}O{sub 12} (BGO) scintillator which was {approx}12 m away from the irradiation point. The range of the flow velocity was 2-11 m/s. The neutron spectrum at the probe section in the SS316/Water assembly was calculated by the MCNP-4B code with the FENDL/E-2.0 library. The cross section data of the {sup 16}O(n, p){sup 16}N reaction was taken from the FENDL/A-2.0 file. The counting response of the BGO detector including the effect of the shielding lead blocks surrounding it was calculated by MCNP-4B. The neutron yield from the water activation has a good agreement with that from associated {alpha} particle detector.

  3. Measuring the absolute deuterium-tritium neutron yield using the magnetic recoil spectrometer at OMEGA and the NIF.

    Science.gov (United States)

    Casey, D T; Frenje, J A; Gatu Johnson, M; Séguin, F H; Li, C K; Petrasso, R D; Glebov, V Yu; Katz, J; Knauer, J P; Meyerhofer, D D; Sangster, T C; Bionta, R M; Bleuel, D L; Döppner, T; Glenzer, S; Hartouni, E; Hatchett, S P; Le Pape, S; Ma, T; MacKinnon, A; McKernan, M A; Moran, M; Moses, E; Park, H-S; Ralph, J; Remington, B A; Smalyuk, V; Yeamans, C B; Kline, J; Kyrala, G; Chandler, G A; Leeper, R J; Ruiz, C L; Cooper, G W; Nelson, A J; Fletcher, K; Kilkenny, J; Farrell, M; Jasion, D; Paguio, R

    2012-10-01

    A magnetic recoil spectrometer (MRS) has been installed and extensively used on OMEGA and the National Ignition Facility (NIF) for measurements of the absolute neutron spectrum from inertial confinement fusion implosions. From the neutron spectrum measured with the MRS, many critical implosion parameters are determined including the primary DT neutron yield, the ion temperature, and the down-scattered neutron yield. As the MRS detection efficiency is determined from first principles, the absolute DT neutron yield is obtained without cross-calibration to other techniques. The MRS primary DT neutron measurements at OMEGA and the NIF are shown to be in excellent agreement with previously established yield diagnostics on OMEGA, and with the newly commissioned nuclear activation diagnostics on the NIF.

  4. Structures of [001] twist boundaries in gold. I. Measurement and use of absolute boundary x-ray structure factors

    Science.gov (United States)

    Taylor, M. S.; Majid, I.; Bristowe, P. D.; Balluffi, R. W.

    1989-08-01

    An x-ray-diffraction method for measuring absolute grain-boundary structure factors is described. The method is based on ratioing appropriate integrated scattered intensities from the grain-boundary region and from the adjoining perfect-crystal region in a bicrystal specimen containing a flat grain boundary. Common unknown factors then cancel out, and an expression for the absolute structure factor is obtained in which all quantities are either known, can be measured, or can be calculated with acceptable accuracy. A practical experimental technique for making the necessary measurements, which employs a four-circle diffractometer, is described. The technique is applied to an x-ray diffraction study of the atomistic structures of a series of [001] twist boundaries in gold in the following paper of our work. The results obtained there clearly demonstrate that the measurement of absolute structure factors, rather than relative structure factors, provides important information in diffraction studies of the structures of grain boundaries, particularly in cases where a limited number of structure factors is measured.

  5. Structures of (001) twist boundaries in gold. I. Measurement and use of absolute boundary x-ray structure factors

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, M.S.; Majid, I.; Bristowe, P.D.; Balluffi, R.W. (Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (US))

    1989-08-15

    An x-ray-diffraction method for measuring absolute grain-boundary structure factors is described. The method is based on ratioing appropriate integrated scattered intensities from the grain-boundary region and from the adjoining perfect-crystal region in a bicrystal specimen containing a flat grain boundary. Common unknown factors then cancel out, and an expression for the absolute structure factor is obtained in which all quantities are either known, can be measured, or can be calculated with acceptable accuracy. A practical experimental technique for making the necessary measurements, which employs a four-circle diffractometer, is described. The technique is applied to an x-ray diffraction study of the atomistic structures of a series of (001) twist boundaries in gold in the following paper of our work. The results obtained there clearly demonstrate that the measurement of absolute structure factors, rather than relative structure factors, provides important information in diffraction studies of the structures of grain boundaries, particularly in cases where a limited number of structure factors is measured.

  6. The research of a method of absolute measurement for laser-driven high pressure equation of state

    CERN Document Server

    Huang Xiu Guang; Gu Yuan; Wu Jian; He Ju Hua; Luo Ping Qing; Ma Min Xun

    2002-01-01

    Numerical simulations of the whole physical process of aluminum flyer-vacuum-target directly driven by high power laser were presented. Simulation results showed that a symmetric impact will be realized between the flyer and the target and there is a wide stable area of shock wave propagation in the target if the parameters of flyer-vacuum-target and the conditions of laser match. And the absolute measurement of equation of state (EOS) may be approached if the structure parameters of flyer both-side-step-target are chosen reasonably. At the same time, the experimental researches of absolute measurement for EOS were conducted, and the experimental results are in accord with the simulation results on the whole

  7. Measurement of the absolute branching ratio of the K+ -> pi+ pi0 (gamma) decay with the KLOE detector

    CERN Document Server

    Ambrosino, F; Antonelli, M; Archilli, F; Bacci, C; Beltrame, P; Bencivenni, G; Bertolucci, S; Bini, C; Bloise, C; Bocchetta, S; Bossi, F; Branchini, P; Campana, P; Capon, G; Capussela, T; Ceradini, F; Cesario, F; Chi, S; Chiefari, G; Ciambrone, P; Crucianelli, F; De Lucia, E; De Santis, A; De Simone, P; De Zorzi, G; Denig, A; Di Domenico, A; Di Donato, C; Di Micco, B; Doria, A; Dreucci, M; Felici, G; Ferrari, A; Ferrer, M L; Fiore, S; Forti, C; Franzini, P; Gatti, C; Gauzzi, P; Giovannella, S; Gorini, E; Graziani, E; Kluge, W; Kulikov, V; Lacava, F; Lanfranchi, G; Lee-Franzini, J; Leone, D; Martemyanov, M; Martini, M; Massarotti, P; Mei, W; Meola, S; Miscetti, S; Moulson, M; Müller, S; Murtas, F; Napolitano, M; Nguyen, F; Palutan, M; Pasqualucci, E; Passeri, A; Patera, V; Perfetto, F; Primavera, M; Santangelo, P; Saracino, G; Sciascia, B; Sciubba, A; Sibidanov, A; Spadaro, T; Testa, M; Tortora, L; Valente, P; Venanzoni, G; Versaci, R; Xu, G

    2008-01-01

    We have measured the absolute branching ratio of the K+ -> pi+ pi0 (gamma) decay, using about 20 million tagged K+ mesons collected with the KLOE detector at DAFNE, the Frascati phi-factory. Signal counts are obtained from the fit of the distribution of the momentum of the charged decay particle in the kaon rest frame. The result, inclusive of final-state radiation, is BR(K+ -> pi+ pi0 (gamma))=0.2065+/-0.0005_{stat}+/- 0.0008_{syst}.

  8. Making sense of absolute measurement: James Clerk Maxwell, William Thomson, Fleeming Jenkin, and the invention of the dimensional formula

    Science.gov (United States)

    Mitchell, Daniel Jon

    2017-05-01

    During the 1860s, the Committee on Electrical Standards convened by the British Association for the Advancement of Science (BAAS) attempted to articulate, refine, and realize a system of absolute electrical measurement. I describe how this context led to the invention of the dimensional formula by James Clerk Maxwell and subsequently shaped its interpretation, in particular through the attempts of William Thomson and Fleeming Jenkin to make absolute electrical measurement intelligible to telegraph engineers. I identify unit conversion as the canonical purpose for dimensional formulae during the remainder of the nineteenth century and go on to explain how an operational interpretation was developed by the French physicist Gabriel Lippmann. The focus on the dimensional formula reveals how various conceptual, theoretical, and material aspects of absolute electrical measurement were taken up or resisted in experimental physics, telegraphic engineering, and electrical practice more broadly, which leads to the conclusion that the integration of electrical theory and telegraphic practice was far harder to achieve and maintain than historians have previously thought. This ultimately left a confusing legacy of dimensional concepts and practices in physics.

  9. 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.

  10. In situ TDLAS measurement of absolute acetylene concentration profiles in a non-premixed laminar counter-flow flame

    Science.gov (United States)

    Wagner, S.; Klein, M.; Kathrotia, T.; Riedel, U.; Kissel, T.; Dreizler, A.; Ebert, V.

    2012-06-01

    Acetylene (C2H2), as an important precursor for chemiluminescence species, is a key to understand, simulate and model the chemiluminescence and the related reaction paths. Hence we developed a high resolution spectrometer based on direct Tunable Diode Laser Absorption Spectroscopy (TDLAS) allowing the first quantitative, calibration-free and spatially resolved in situ C2H2 measurement in an atmospheric non-premixed counter-flow flame supported on a Tsuji burner. A fiber-coupled distributed feedback diode laser near 1535 nm was used to measure several absolute C2H2 concentration profiles (peak concentrations up to 9700 ppm) in a laminar non-premixed CH4/air flame ( T up to 1950 K) supported on a modified Tsuji counter-flow burner with N2 purge slots to minimize end flames. We achieve a fractional optical resolution of up to 5×10-5 OD (1 σ) in the flame, resulting in temperature-dependent acetylene detection limits for the P17e line at 6513 cm-1 of up to 2.1 ppmṡm. Absolute C2H2 concentration profiles were obtained by translating the burner through the laser beam using a DC motor with 100 μm step widths. Intercomparisons of the experimental C2H2 profiles with simulations using our new hydrocarbon oxidation mechanisms show excellent agreement in position, shape and in the absolute C2H2 values.

  11. Accurate Lifetimes and Absolute Transition Rates for Ultraviolet Transitions from 3D5(4G) 4P and 3D5(4P) 4P levels in MN II

    Science.gov (United States)

    Kling, Rainer; Schnabel, Roman; Griesmann, Ulf

    2001-05-01

    A recently developed, laser-induced fluorescence technique was used to measure the lifetimes of 14 3d5(4G)4p and 3d5(4P)4p levels in the Mn+ ion. Branching fractions for electric dipole transitions from these levels were measured with a vacuum ultraviolet Fourier transform spectrometer, using a hollow-cathode lamp and a Penning discharge source. Based on these new measurements, absolute electric dipole transition rates for about 170 spectral lines in the ultraviolet and vacuum ultraviolet were determined. The uncertainty of the transition rates is less than 5% for the strong transitions.

  12. Absolute nuclear material assay

    Science.gov (United States)

    Prasad, Manoj K [Pleasanton, CA; Snyderman, Neal J [Berkeley, CA; Rowland, Mark S [Alamo, CA

    2012-05-15

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  13. Absolute nuclear material assay

    Science.gov (United States)

    Prasad, Manoj K [Pleasanton, CA; Snyderman, Neal J [Berkeley, CA; Rowland, Mark S [Alamo, CA

    2010-07-13

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  14. Measurements of absolute M-subshell X-ray production cross sections of Th by electron impact

    Energy Technology Data Exchange (ETDEWEB)

    Moy, A., E-mail: aurelien.moy@cea.fr [GM, CNRS, Université de Montpellier II, Place E. Bataillon, F-34095 Montpellier (France); CEA, DEN, DTEC, SGCS, LMAC, F-30207 Bagnols-sur-Cèze (France); Merlet, C. [GM, CNRS, Université de Montpellier II, Place E. Bataillon, F-34095 Montpellier (France); Dugne, O. [CEA, DEN, DTEC, SGCS, LMAC, F-30207 Bagnols-sur-Cèze (France)

    2014-08-31

    Highlights: • The M X-ray production cross sections of Th were measured by electron impact. • The M-subshell ionization cross sections of Th were determined from 3 to 38 keV. • Theoretical ionization cross-sections are in agreement with our experimental results. - Abstract: Measurements of absolute M-subshell X-ray production cross sections for element Th were made by electron impact for energies ranging from the ionization threshold up to 38 keV. Experimental data were obtained by measuring the X-ray intensity emitted from ultrathin Th films deposited onto self-supporting C backing films. The measurements were conducted with an electron microprobe using high-resolution wavelength dispersive spectrometers. Recorded intensities were converted into absolute X-ray production cross sections by means of atomic data and estimation of the number of primary electrons, target thickness, and detector efficiency. Our experimental X-ray production cross sections, the first to be reported for the M subshells of Th, are compared with X-ray production cross sections calculated with the mean of ionization cross sections obtained from the distorted-wave Born approximation. The Mα X-ray production cross section calculated is in excellent agreement with the measurements, allowing future use for standardless quantification in electron probe microanalysis.

  15. Ocean Lidar Measurements of Beam Attenuation and a Roadmap to Accurate Phytoplankton Biomass Estimates

    Directory of Open Access Journals (Sweden)

    Hu Yongxiang

    2016-01-01

    On July 17, 2014, the CALIPSO satellite was tilted 30° off-nadir for one nighttime orbit in order to minimize ocean surface backscatter and demonstrate the lidar ocean subsurface measurement concept from space. Depolarization ratios of ocean subsurface backscatter are measured accurately. Beam attenuation coefficients computed from the depolarization ratio measurements compare well with empirical estimates from ocean color measurements. We further verify the beam attenuation coefficient retrievals using aircraft-based high spectral resolution lidar (HSRL data that are collocated with in-water optical measurements.

  16. Radiometric absolute noise-temperature measurement system features improved accuracy and calibration ease

    Science.gov (United States)

    Brown, W.; Ewen, H.; Haroules, G.

    1970-01-01

    Radiometric receiver system, which measures noise temperatures in degrees Kelvin, does not require cryogenic noise sources for routine operation. It eliminates radiometer calibration errors associated with RF attenuation measurements. Calibrated noise source is required only for laboratory adjustment and calibration.

  17. Short pulse carrier-envelope phase absolute single-shot measurement by photoionization of gases with a guided laser beam.

    Science.gov (United States)

    Strelkov, V V; Mével, E; Constant, E

    2014-03-24

    We present an all optical approach to measure the value of the carrier-envelope phase (CEP) of a short intense laser pulse. This method relies on photo-ionization of gases with a guided laser beam. This approach that provides the absolute value of the CEP, is compatible with single shot characterization, is scalable in wavelength, does not suffer from bandwidth limitation and is largely intensity independent. It has also the potential to provide a full characterization of the pulse profile via high order autocorrelation on a single shot basis.

  18. 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...

  19. 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.

  20. Measurement of the absolute vμ-CCQE cross section at the SciBooNE experiment

    Energy Technology Data Exchange (ETDEWEB)

    Aunion, Jose Luis Alcaraz [Autonomous Univ. of Barcelona (Spain)

    2010-07-01

    This thesis presents the measurement of the charged current quasi-elastic (CCQE) neutrino-nucleon cross section at neutrino energies around 1 GeV. This measurement has two main physical motivations. On one hand, the neutrino-nucleon interactions at few GeV is a region where existing old data are sparse and with low statistics. The current measurement populates low energy regions with higher statistics and precision than previous experiments. On the other hand, the CCQE interaction is the most useful interaction in neutrino oscillation experiments. The CCQE channel is used to measure the initial and final neutrino fluxes in order to determine the neutrino fraction that disappeared. The neutrino oscillation experiments work at low neutrino energies, so precise measurement of CCQE interactions are essential for flux measurements. The main goal of this thesis is to measure the CCQE absolute neutrino cross section from the SciBooNE data. The SciBar Booster Neutrino Experiment (SciBooNE) is a neutrino and anti-neutrino scattering off experiment. The neutrino energy spectrum works at energies around 1 GeV. SciBooNE was running from June 8th 2007 to August 18th 2008. In that period, the experiment collected a total of 2.65 x 1020 protons on target (POT). This thesis has used full data collection in neutrino mode 0.99 x 1020 POT. A CCQE selection cut has been performed, achieving around 70% pure CCQE sample. A fit method has been exclusively developed to determine the absolute CCQE cross section, presenting results in a neutrino energy range from 0.2 to 2 GeV. The results are compatible with the NEUT predictions. The SciBooNE measurement has been compared with both Carbon (MiniBoonE) and deuterium (ANL and BNL) target experiments, showing a good agreement in both cases.

  1. Effect of self-vibration on accuracy of free-fall absolute gravity measurement with laser interferometer

    Science.gov (United States)

    Feng, Jin-yang; Wu, Shu-qing; Li, Chun-jian; Su, Duo-wu; Yu, Mei

    2015-02-01

    A free-fall absolute gravimeter was used to measure the gravity acceleration of a corner-cube released in high vacuum, and the gravity acceleration was determined by fitting the free-falling trajectories obtained through optical interferometry. During the measurement, the self-vibration of an absolute gravimeter caused ground vibration and the change in optical path length due to vibration of vacuum-air interface, which resulted in a measurement error. Numerical simulation was run by introducing vibration disturbance to the trajectories of free-fall. The effect of disturbance under different instrumental self-vibration conditions was analyzed. Simulation results indicated that the deviation of calculated gravity acceleration from the preset value and residuals amplitude after fitting depended on the amplitude and initial phase of the vibration disturbance. The deviation value and fitting residuals amplitude increased with the increasing of amplitude and there was a one-to-one correspondence between the two. The deviation of calculated gravity acceleration decreases by properly setting the initial phase difference of vibration disturbance with respect to the interference fringe signal.

  2. Low-cost small action cameras in stereo generates accurate underwater measurements of fish

    OpenAIRE

    Letessier, T. B.; Juhel, Jean-Baptiste; Vigliola, Laurent; Meeuwig, J. J.

    2015-01-01

    Small action cameras have received interest for use in underwater videography because of their low-cost, standardised housing, widespread availability and small size. Here, we assess the capacity of GoPro action cameras to provide accurate stereo-measurements of fish in comparison to the Sony handheld cameras that have traditionally been used for this purpose. Standardised stereo-GoPro and Sony systems were employed to capture measurements of known-length targets in a pool to explore the infl...

  3. The mean machine; accurate non-invasive blood pressure measurement in the critically ill patient.

    Science.gov (United States)

    Muecke, Sandy; Bersten, Andrew; Plummer, John

    2009-10-01

    Accurate indirect prehospital blood pressure measurement in the critically ill patient remains an important challenge to both patient management and prehospital research. Ambulatory blood pressure measuring devices have not been trialled for prehospital use in critically ill patients. Prior to prehospital validation where conditions are suboptimal, we aimed to test under favourable conditions in the Intensive Care Unit, a selection of ambulatory devices that may be suitable for use in the field. Systolic, diastolic and mean pressures of three ambulatory devices were compared to the average of 1 min of independently recorded, high fidelity intra-arterial reference pressures. Eighteen critically ill patients were recruited. Device performance was required to fulfil the Association for the Advancement of Medical Instrumentation (AAMI) protocol. Additionally, agreement between measurement methods was examined using Bland-Altman plots. Two-level linear mixed model analyses were under- taken. For each device, 150 paired measurements (arterial reference and device) were analysed. According to the AAMI protocol, no device measured systolic pressures accurately. One device measured diastolic pressures accurately. Integrated mean pressures were accurately measured by all devices. Overall, SunTech Medical's Oscar 2 performed best with mean pressure error not exceeding 17 mmHg. For this device, Bland-Altman plots showed uniform agreement across a wide range of mean pressures. Two-level linear mixed effects analyses showed that Oscar 2 mean error reduced during vasopressor use by (-) 3.9 mmHg (95% CI -5.9, -1.9; P tension. In the Intensive Care Unit, the performance of one device, the Oscar 2, surpassed the others and fulfilled the AAMI protocol criteria for mean pressure measurement. This device is suitable for prehospital validation.

  4. High-accuracy absolute rotation rate measurements with a large ring laser gyro: establishing the scale factor.

    Science.gov (United States)

    Hurst, Robert B; Mayerbacher, Marinus; Gebauer, Andre; Schreiber, K Ulrich; Wells, Jon-Paul R

    2017-02-01

    Large ring lasers have exceeded the performance of navigational gyroscopes by several orders of magnitude and have become useful tools for geodesy. In order to apply them to tests in fundamental physics, remaining systematic errors have to be significantly reduced. We derive a modified expression for the Sagnac frequency of a square ring laser gyro under Earth rotation. The modifications include corrections for dispersion (of both the gain medium and the mirrors), for the Goos-Hänchen effect in the mirrors, and for refractive index of the gas filling the cavity. The corrections were measured and calculated for the 16  m2 Grossring laser located at the Geodetic Observatory Wettzell. The optical frequency and the free spectral range of this laser were measured, allowing unique determination of the longitudinal mode number, and measurement of the dispersion. Ultimately we find that the absolute scale factor of the gyroscope can be estimated to an accuracy of approximately 1 part in 108.

  5. Highly resolved HSQC experiments for the fast and accurate measurement of homonuclear and heteronuclear coupling constants

    Science.gov (United States)

    Souza, Alexandre A.; Gil, Roberto R.; Parella, Teodor

    2017-09-01

    A number of J-upscaled NMR experiments are currently available to measure coupling constants along the indirect F1 dimension of a 2D spectrum. A major drawback is the limited F1 digital resolution that requires long acquisition times in order to achieve reasonably accurate measures. Here is shown how high levels of F1 digital resolution in a multiple-purpose HSQC experiment can be easily achieved by implementing a general J/δ-scaling strategy. In particular, a set of new J-resolved HSQC experiments is presented for a faster and much more accurate J determination in small molecules. Several options and practical aspects are discussed and exemplified by measuring the magnitude and/or the sign of several homo- and heteronuclear coupling constants in one shot.

  6. Calibration of the Odyssey Photosynthetic Irradiance Recorder for Absolute Irradiance Measures

    Science.gov (United States)

    Researchers are increasingly interested in measuring hotosynthetically active radiation (PAR) because of its importance in determining the structure and function of lotic ecosystems. The Odyssey Photosynthetic Irradiance Recorder is an affordable PAR meter gaining popularity am...

  7. Measurement of absolute displacement-amplitude of ultrasonic wave using piezo-electric detection method

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seong Hyun; Kim, Jong Beom; Jhang, Kyung Young [Hanyang University, Seoul (Korea, Republic of)

    2017-02-15

    A nonlinear ultrasonic parameter is defined by the ratio of displacement amplitude of the fundamental frequency component to that of the second-order harmonic frequency component. In this study, the ultrasonic displacement amplitude of an SUS316 specimen was measured via a piezo-electric-based method to identify the validity of piezo-electric detection method. For comparison, the ultrasonic displacement was also determined via a laser-based Fabry-Pérot interferometer. The experimental results for both measurements were in good agreement. Additionally, the stability of the repeated test results from the piezo-electric method exceeded that of the laser-interferometric method. This result indicated that the piezo-electric detection method can be utilized to measure a nonlinear ultrasonic parameter due to its excellent stability although it involves a complicated process.

  8. More accurate systolic blood pressure measurement is required for improved hypertension management: a perspective.

    Science.gov (United States)

    Nitzan, Meir; Slotki, Itzchak; Shavit, Linda

    2017-01-01

    The commonly used techniques for systolic blood pressure (SBP) and diastolic blood pressure (DBP) measurement are the auscultatory Korotkoff-based sphygmomanometry and oscillometry. The former technique is relatively accurate but is limited to a physician's office because its automatic variant is subject to noise artifacts. Consequently, the Korotkoff-based measurement overestimates the blood pressure in some patients due to white coat effect, and because it is a single measurement, it cannot properly represent the variable blood pressure. Automatic oscillometry can be used at home by the patient and is preferred even in clinics. However, the technique's accuracy is low and errors of 10-15 mmHg are common. Recently, we have developed an automatic technique for SBP measurement, based on an arm pressure cuff and a finger photoplethysmographic probe. The technique was found to be significantly more accurate than oscillometry, and comparable to the Korotkoff-based technique, the reference-standard for non-invasive blood pressure measurements. The measurement of SBP is a mainstay for the diagnosis and follow-up of hypertension, which is a major risk factor for several adverse events, mainly cardiovascular. Lowering blood pressure evidently reduces the risk, but excessive lowering can result in hypotension and consequently hypoperfusion to vital organs, since blood pressure is the driving force for blood flow. Erroneous measurement by 10 mmHg can lead to a similar unintended reduction of SBP and may adversely affect patients treated to an SBP of 120-130 mmHg. In particular, in elderly patients, unintended excessive reduction of blood pressure due to inaccurate SBP measurement can result in cerebral hypoperfusion and consequent cognitive decline. By using a more accurate technique for automatic SBP measurement (such as the photoplethysmographic-based technique), the optimal blood pressure target can be achieved with lower risk for hypotension and its adverse events.

  9. Anthropometric measures are not accurate predictors of fat mass in ALS.

    Science.gov (United States)

    Ioannides, Zara A; Steyn, Frederik J; Henderson, Robert D; Mccombe, Pamela A; Ngo, Shyuan T

    2017-11-01

    Anthropometric measurements including body mass index (BMI) and body adiposity index (BAI) are widely employed as indicators of fat mass (FM). Metabolic abnormalities in amyotrophic lateral sclerosis (ALS) impact disease progression, therefore assessment of FM informs care. The aim of this study was to determine whether BMI and BAI are accurate predictors of FM in ALS. Methodology and main findings: BMI, BAI and percentage FM (determined by air displacement plethysmography; FM-ADP) were measured in control (n = 35) and ALS (n = 44) participants. While BMI and BAI correlated significantly with FM-ADP, neither index provided an accurate estimate of FM. In longitudinally assessed ALS participants (n = 29; ∼six-month repeat assessment interval), although a change in BMI (r 2  = 0.62 r = 0.79 p FM-ADP, the anthropometric measures did not consistently reflect increases or decreases observed in FM-ADP. Using FM-ADP as the standard, this study suggests that BMI and BAI are not accurate measures of FM in ALS. Furthermore, longitudinal assessments indicate that changes in BMI and BAI do not consistently reflect true changes of FM in ALS.

  10. 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.

  11. Solid-state track recorder dosimetry device to measure absolute reaction rates and neutron fluence as a function of time

    Science.gov (United States)

    Gold, Raymond; Roberts, James H.

    1989-01-01

    A solid state track recording type dosimeter is disclosed to measure the time dependence of the absolute fission rates of nuclides or neutron fluence over a period of time. In a primary species an inner recording drum is rotatably contained within an exterior housing drum that defines a series of collimating slit apertures overlying windows defined in the stationary drum through which radiation can enter. Film type solid state track recorders are positioned circumferentially about the surface of the internal recording drum to record such radiation or its secondary products during relative rotation of the two elements. In another species both the recording element and the aperture element assume the configuration of adjacent disks. Based on slit size of apertures and relative rotational velocity of the inner drum, radiation parameters within a test area may be measured as a function of time and spectra deduced therefrom.

  12. 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

  13. Usability of a Fourier transform spectroradiometer for absolute surface spectral solar UV irradiance measurements.

    Science.gov (United States)

    Meindl, Peter; Wähmer, Martin; Monte, Christian

    2014-10-20

    The suitability of a commercially available Fourier transform spectrometer equipped with a fiber-coupled global entrance optic as a reference spectroradiometer for the measurement of spectral solar ultraviolet irradiance at ground level has been investigated. The instrument has been characterized with respect to the wavelength uncertainty, and a calibration of the spectral irradiance responsivity has been performed by using the calculable irradiance of a high temperature black-body radiator and by using a secondary irradiance standard lamp. The relative standard uncertainty of solar irradiance measurements in the wavelength range from 310 nm to 400 nm with this spectroradiometer, based on the described methodology, is 1.6% for solar zenith angles of less than 60°.

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

    DEFF Research Database (Denmark)

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

    2009-01-01

    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......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...... with sufficient accuracy. As an example, the sheet resistance of a 40 µm (50 µm) square sample may be characterized with an accuracy of 0.3% (0.1%) using a 10 µm pitch microfour-point probe and assuming a probe alignment accuracy of ±2.5 µm. ©2009 American Institute of Physics...

  15. 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.

  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. Precise and accurate measurements of strong-field photoionisation and a transferrable laser intensity calibration standard

    CERN Document Server

    Wallace, W C; Khurmi, C; U., Satya Sainadh; Calvert, J E; Laban, D E; Pullen, M G; Bartschat, K; Grum-Grzhimailo, A N; Wells, D; Quiney, H M; Tong, X M; Litvinyuk, I V; Sang, R T; Kielpinski, D

    2016-01-01

    Ionization of atoms and molecules in strong laser fields is a fundamental process in many fields of research, especially in the emerging field of attosecond science. So far, demonstrably accurate data have only been acquired for atomic hydrogen (H), a species that is accessible to few investigators. Here we present measurements of the ionization yield for argon, krypton, and xenon with percentlevel accuracy, calibrated using H, in a laser regime widely used in attosecond science. We derive a transferrable calibration standard for laser peak intensity, accurate to 1.3%, that is based on a simple reference curve. In addition, our measurements provide a much-needed benchmark for testing models of ionisation in noble-gas atoms, such as the widely employed single-active electron approximation.

  18. Are external knee load and EMG measures accurate indicators of internal knee contact forces during gait?

    Science.gov (United States)

    Meyer, Andrew J; D'Lima, Darryl D; Besier, Thor F; Lloyd, David G; Colwell, Clifford W; Fregly, Benjamin J

    2013-06-01

    Mechanical loading is believed to be a critical factor in the development and treatment of knee osteoarthritis. However, the contact forces to which the knee articular surfaces are subjected during daily activities cannot be measured clinically. Thus, the ability to predict internal knee contact forces accurately using external measures (i.e., external knee loads and muscle electromyographic [EMG] signals) would be clinically valuable. We quantified how well external knee load and EMG measures predict internal knee contact forces during gait. A single subject with a force-measuring tibial prosthesis and post-operative valgus alignment performed four gait patterns (normal, medial thrust, walking pole, and trunk sway) to induce a wide range of external and internal knee joint loads. Linear regression analyses were performed to assess how much of the variability in internal contact forces was accounted for by variability in the external measures. Though the different gait patterns successfully induced significant changes in the external and internal quantities, changes in external measures were generally weak indicators of changes in total, medial, and lateral contact force. Our results suggest that when total contact force may be changing, caution should be exercised when inferring changes in knee contact forces based on observed changes in external knee load and EMG measures. Advances in musculoskeletal modeling methods may be needed for accurate estimation of in vivo knee contact forces. Copyright © 2012 Orthopaedic Research Society.

  19. Measurement error correction in the least absolute shrinkage and selection operator model when validation data are available.

    Science.gov (United States)

    Vasquez, Monica M; Hu, Chengcheng; Roe, Denise J; Halonen, Marilyn; Guerra, Stefano

    2017-01-01

    Measurement of serum biomarkers by multiplex assays may be more variable as compared to single biomarker assays. Measurement error in these data may bias parameter estimates in regression analysis, which could mask true associations of serum biomarkers with an outcome. The Least Absolute Shrinkage and Selection Operator (LASSO) can be used for variable selection in these high-dimensional data. Furthermore, when the distribution of measurement error is assumed to be known or estimated with replication data, a simple measurement error correction method can be applied to the LASSO method. However, in practice the distribution of the measurement error is unknown and is expensive to estimate through replication both in monetary cost and need for greater amount of sample which is often limited in quantity. We adapt an existing bias correction approach by estimating the measurement error using validation data in which a subset of serum biomarkers are re-measured on a random subset of the study sample. We evaluate this method using simulated data and data from the Tucson Epidemiological Study of Airway Obstructive Disease (TESAOD). We show that the bias in parameter estimation is reduced and variable selection is improved.

  20. A new method for the absolute radiance calibration for UV/vis measurements of scattered sun light

    Science.gov (United States)

    Wagner, T.; Beirle, S.; Dörner, S.; Penning de Vries, M.; Remmers, J.; Rozanov, A.; Shaiganfar, R.

    2015-05-01

    Absolute radiometric calibrations are important for measurements of the atmospheric spectral radiance. Such measurements can be used to determine actinic fluxes, the properties of aerosols and clouds and the short wave energy budget. Conventional calibration methods in the laboratory are based on calibrated light sources and reflectors and are expensive, time consuming and subject to relatively large uncertainties. Also, the calibrated instruments might change during transport from the laboratory to the measurement sites. Here we present a new calibration method for UV/vis instruments that measure the spectrally resolved sky radiance, like for example zenith sky Differential Optical Absorption Spectroscopy (DOAS-) instruments or Multi-AXis (MAX-) DOAS instruments. Our method is based on the comparison of the solar zenith angle dependence of the measured zenith sky radiance with radiative transfer simulations. For the application of our method clear sky measurements during periods with almost constant aerosol optical depth are needed. The radiative transfer simulations have to take polarisation into account. We show that the calibration results are almost independent from the knowledge of the aerosol optical properties and surface albedo, which causes a rather small uncertainty of about ozone column density during the measurements is constant and known.

  1. A Novel Multimode Waveguide Coupler for Accurate Power Measurement of Traveling Wave Tube Harmonic Frequencies

    Science.gov (United States)

    Wintucky, Edwin G.; Simons, Rainee N.

    2014-01-01

    This paper presents the design, fabrication and test results for a novel waveguide multimode directional coupler (MDC). The coupler fabricated from two dissimilar waveguides is capable of isolating the power at the second harmonic frequency from the fundamental power at the output port of a traveling-wave tube (TWT). In addition to accurate power measurements at harmonic frequencies, a potential application of the MDC is in the design of a beacon source for atmospheric propagation studies at millimeter-wave frequencies.

  2. Accurate Measurements of Aerosol Hygroscopic Growth over a Wide Range in Relative Humidity.

    Science.gov (United States)

    Rovelli, Grazia; Miles, Rachael E H; Reid, Jonathan P; Clegg, Simon L

    2016-06-30

    Using a comparative evaporation kinetics approach, we describe a new and accurate method for determining the equilibrium hygroscopic growth of aerosol droplets. The time-evolving size of an aqueous droplet, as it evaporates to a steady size and composition that is in equilibrium with the gas phase relative humidity, is used to determine the time-dependent mass flux of water, yielding information on the vapor pressure of water above the droplet surface at every instant in time. Accurate characterization of the gas phase relative humidity is provided from a control measurement of the evaporation profile of a droplet of know equilibrium properties, either a pure water droplet or a sodium chloride droplet. In combination, and by comparison with simulations that account for both the heat and mass transport governing the droplet evaporation kinetics, these measurements allow accurate retrieval of the equilibrium properties of the solution droplet (i.e., the variations with water activity in the mass fraction of solute, diameter growth factor, osmotic coefficient or number of water molecules per solute molecule). Hygroscopicity measurements can be made over a wide range in water activity (from >0.99 to, in principle, 0.9 and ∼±1% below 80% RH, and maximum uncertainties in diameter growth factor of ±0.7%. For all of the inorganic systems examined, the time-dependent data are consistent with large values of the mass accommodation (or evaporation) coefficient (>0.1).

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

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Zhi-Jun [Dept. of Radiology, North China Petroleum Bureau General Hospital, Renqiu, Hebei (China)], e-mail: Gzj3@163.com; Lin, Qiang [Dept. of Oncology, North China Petroleum Bureau General Hospital, Renqiu, Hebei (China); Liu, Hai-Tao [Dept. of General Surgery, North China Petroleum Bureau General Hospital, Renqiu, Hebei (China)] [and others])

    2013-09-15

    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

  4. Assessing the repeatability of absolute CMRO2, OEF and haemodynamic measurements from calibrated fMRI.

    Science.gov (United States)

    Merola, Alberto; Germuska, Michael A; Murphy, Kevin; Wise, Richard G

    2018-02-14

    As energy metabolism in the brain is largely oxidative, the measurement of cerebral metabolic rate of oxygen consumption (CMRO 2 ) is a desirable biomarker for quantifying brain activity and tissue viability. Currently, PET techniques based on oxygen isotopes are the gold standard for obtaining whole brain CMRO 2 maps. Among MRI techniques that have been developed as an alternative are dual calibrated fMRI (dcFMRI) methods, which exploit simultaneous measurements of BOLD and ASL signals during a hypercapnic-hyperoxic experiment to modulate brain blood flow and oxygenation. In this study we quantified the repeatability of a dcFMRI approach developed in our lab, evaluating its limits and informing its application in studies aimed at characterising the metabolic state of human brain tissue over time. Our analysis focussed on the estimates of oxygen extraction fraction (OEF), cerebral blood flow (CBF), CBF-related cerebrovascular reactivity (CVR) and CMRO 2 based on a forward model that describes analytically the acquired dual echo GRE signal. Indices of within- and between-session repeatability are calculated from two different datasets both at a bulk grey matter and at a voxel-wise resolution and finally compared with similar indices obtained from previous MRI and PET measurements. Within- and between-session values of intra-subject coefficient of variation (CV intra ) calculated from bulk grey matter estimates 6.7 ± 6.6% (mean ± std.) and 10.5 ± 9.7% for OEF, 6.9 ± 6% and 5.5 ± 4.7% for CBF, 12 ± 9.7% and 12.3 ± 10% for CMRO 2 . Coefficient of variation (CV) and intraclass correlation coefficient (ICC) maps showed the spatial distribution of the repeatability metrics, informing on the feasibility limits of the method. In conclusion, results show an overall consistency of the estimated physiological parameters with literature reports and a satisfactory level of repeatability considering the higher spatial sensitivity compared to

  5. Accurate measurement of cortical bone elasticity tensor with resonant ultrasound spectroscopy.

    Science.gov (United States)

    Bernard, Simon; Grimal, Quentin; Laugier, Pascal

    2013-02-01

    Resonant ultrasound spectroscopy (RUS) allows to accurately characterize the complete set of elastic constants of an anisotropic material from a set of measured mechanical resonant frequencies of a specimen. This method does not suffer from the drawbacks and limitations of the conventional sound velocity approach, but has been reported to fail to measure bone because of its strong viscoelastic damping. In this study, we take advantage of recent developments of RUS to overcome this limitation. The frequency response of a human cortical bone specimen (about 5 × 7 × 7 mm(3)) was measured between 100 and 280 kHz. Despite an important overlapping of the resonant peaks 20 resonant frequencies could be retrieved by using a dedicated signal processing method. The experimental frequencies were progressively matched to the frequencies predicted by a model of the sample whose elastic constants were adjusted. The determined diagonal elastic constants were in good agreement with concurrent sound velocity measurements performed in the principal directions of the specimen. This study demonstrates that RUS is suitable for an accurate measurement of cortical bone anisotropic elasticity. In particular, precision of measured Young and shear moduli is about 0.5%. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. 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.

  7. Absolute measurement of absorption and scattering coefficients spectra of a multiply scattering medium

    Science.gov (United States)

    Fantini, Sergio; Franceschini, Maria-Angela; Fishkin, Joshua B.; Gratton, Enrico

    1994-07-01

    On the basis of the diffusion theory model, frequency-domain spectroscopy allows for a quantitative determination of the absorption ((mu) a) and scattering ((mu) s') coefficient spectra of a homogeneous multiple scattering medium. We performed measurements using an intensity modulated light emitting diode (LED) as the light source. The LED's spectral distribution permits the study of a spectral region extending for about 80 nm. Data sets (phase shift and average intensity) at two different source-detector distances are acquired: the absorption and scattering coefficient spectra of the medium are then calculated from analytical expressions for (mu) a and (mu) s'. Methylene blue (peak absorption wavelength 656 nm) is used as a test absorbing material. The methylene blue is dissolved in an aqueous Liposyn solution which serves as the multiple scattering medium. The relative amounts of absorber and scatterer are chosen such that the values of (mu) a and (mu) s' match typical values in tissues. The results obtained for (mu) a((lambda) ) with this LED based technique are in quantitative agreement with those obtained with a standard spectrophotometer in a nonscattering regime.

  8. Absolute Zero

    Science.gov (United States)

    Donnelly, Russell J.; Sheibley, D.; Belloni, M.; Stamper-Kurn, D.; Vinen, W. F.

    2006-12-01

    Absolute Zero is a two hour PBS special attempting to bring to the general public some of the advances made in 400 years of thermodynamics. It is based on the book “Absolute Zero and the Conquest of Cold” by Tom Shachtman. Absolute Zero will call long-overdue attention to the remarkable strides that have been made in low-temperature physics, a field that has produced 27 Nobel Prizes. It will explore the ongoing interplay between science and technology through historical examples including refrigerators, ice machines, frozen foods, liquid oxygen and nitrogen as well as much colder fluids such as liquid hydrogen and liquid helium. A website has been established to promote the series: www.absolutezerocampaign.org. It contains information on the series, aimed primarily at students at the middle school level. There is a wealth of material here and we hope interested teachers will draw their student’s attention to this website and its substantial contents, which have been carefully vetted for accuracy.

  9. Assessment of air space size characteristics by intercept (chord) measurement: an accurate and efficient stereological approach.

    Science.gov (United States)

    Knudsen, Lars; Weibel, Ewald R; Gundersen, Hans Jørgen G; Weinstein, Felix V; Ochs, Matthias

    2010-02-01

    The mean linear intercept (chord) length (L(m)) is a useful parameter of peripheral lung structure as it describes the mean free distance in the air spaces. It is often misinterpreted as a measure of "alveolar size," and its estimation is fraught with a number of pitfalls. We present two methods for the accurate estimation of L(m): 1) the indirect method, which derives L(m) from the volume-to-surface ratio of air spaces estimated by point counting methods, and 2) the direct method, which uses a set of random intercepts and calculates L(m) from their frequency distribution, for which we introduce a new and accurate method. Both methods are efficient and, with proper precautions, unbiased. The meaning of L(m) is assessed in two different examples. In a physiological study, the effect of different inflation levels is studied, showing that L(m) critically depends on lung inflation. In an experimental study on emphysema-like changes in a genetic mouse model, the effect of heterogeneity of air space size is assessed; these results are obtained partly because of differences in lung volume due to altered recoil in the emphysematous lungs. In conclusion, although L(m) is not a robust parameter of internal lung structure because it crucially depends on lung volume, it is still a valid measure for which accurate and efficient methods are available that yield additional parameters such as size distribution or alveolar surface area.

  10. Procoagulant and platelet-derived microvesicle absolute counts determined by flow cytometry correlates with a measurement of their functional capacity

    Directory of Open Access Journals (Sweden)

    Lisa Ayers

    2014-09-01

    Full Text Available Background: Flow cytometry is the most commonly used technology to measure microvesicles (MVs. Despite reported limitations of this technique, MV levels obtained using conventional flow cytometry have yielded many clinically relevant findings, such as associations with disease severity and ability to predict clinical outcomes. This study aims to determine if MV enumeration by flow cytometry correlates with a measurement of their functional capacity, as this may explain how flow cytometry generates clinically relevant results. Methods: One hundred samples from healthy individuals and patients with obstructive sleep apnoea were analysed by conventional flow cytometry (FACSCalibur and by three functional MV assays: Zymuphen MP-activity in which data were given as phosphatidylserine equivalent, STA® Phospholipid Procoag Assay expressed as clotting time and Endogenous Thrombin Potential (ETP reflecting in vitro thrombin generation. Correlations were determined by Spearman correlation. Results: Absolute counts of lactadherin+ procoagulant MVs generated by flow cytometry weakly correlated with the results obtained from the Zymuphen MP-activity (r=0.5370, p<0.0001; correlated with ETP (r=0.7444, p<0.0001; negatively correlated with STA® Phospholipid Procoag Assay clotting time (−0.7872, p<0.0001, reflecting a positive correlation between clotting activity and flow cytometry. Levels of Annexin V+ procoagulant and platelet-derived MVs were also associated with functional assays. Absolute counts of MVs derived from other cell types were not correlated with the functional results. Conclusions: Quantitative results of procoagulant and platelet-derived MVs from conventional flow cytometry are associated with the functional capability of the MVs, as defined by three functional MV assays. Flow cytometry is a valuable technique for the quantification of MVs from different cellular origins; however, a combination of several analytical techniques may give the

  11. Procoagulant and platelet-derived microvesicle absolute counts determined by flow cytometry correlates with a measurement of their functional capacity.

    Science.gov (United States)

    Ayers, Lisa; Harrison, Paul; Kohler, Malcolm; Ferry, Berne

    2014-01-01

    Flow cytometry is the most commonly used technology to measure microvesicles (MVs). Despite reported limitations of this technique, MV levels obtained using conventional flow cytometry have yielded many clinically relevant findings, such as associations with disease severity and ability to predict clinical outcomes. This study aims to determine if MV enumeration by flow cytometry correlates with a measurement of their functional capacity, as this may explain how flow cytometry generates clinically relevant results. ONE HUNDRED SAMPLES FROM HEALTHY INDIVIDUALS AND PATIENTS WITH OBSTRUCTIVE SLEEP APNOEA WERE ANALYSED BY CONVENTIONAL FLOW CYTOMETRY (FACSCALIBUR) AND BY THREE FUNCTIONAL MV ASSAYS: Zymuphen MP-activity in which data were given as phosphatidylserine equivalent, STA(®) Phospholipid Procoag Assay expressed as clotting time and Endogenous Thrombin Potential (ETP) reflecting in vitro thrombin generation. Correlations were determined by Spearman correlation. Absolute counts of lactadherin+ procoagulant MVs generated by flow cytometry weakly correlated with the results obtained from the Zymuphen MP-activity (r=0.5370, pflow cytometry. Levels of Annexin V+ procoagulant and platelet-derived MVs were also associated with functional assays. Absolute counts of MVs derived from other cell types were not correlated with the functional results. Quantitative results of procoagulant and platelet-derived MVs from conventional flow cytometry are associated with the functional capability of the MVs, as defined by three functional MV assays. Flow cytometry is a valuable technique for the quantification of MVs from different cellular origins; however, a combination of several analytical techniques may give the most comprehensive information on the role of MVs in health and disease.

  12. No galaxy left behind: accurate measurements with the faintest objects in the Dark Energy Survey

    Science.gov (United States)

    Suchyta, E.; Huff, E. M.; Aleksić, J.; Melchior, P.; Jouvel, S.; MacCrann, N.; Ross, A. J.; Crocce, M.; Gaztanaga, E.; Honscheid, K.; Leistedt, B.; Peiris, H. V.; Rykoff, E. S.; Sheldon, E.; Abbott, T.; Abdalla, F. B.; Allam, S.; Banerji, M.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Burke, D. L.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Estrada, J.; Evrard, A. E.; Flaugher, B.; Fosalba, P.; Frieman, J.; Gerdes, D. W.; Gruen, D.; Gruendl, R. A.; James, D. J.; Jarvis, M.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Lima, M.; Maia, M. A. G.; March, M.; Marshall, J. L.; Miller, C. J.; Miquel, R.; Neilsen, E.; Nichol, R. C.; Nord, B.; Ogando, R.; Percival, W. J.; Reil, K.; Roodman, A.; Sako, M.; Sanchez, E.; Scarpine, V.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Thomas, D.; Vikram, V.; Walker, A. R.; Wechsler, R. H.; Zhang, Y.; DES Collaboration

    2016-03-01

    Accurate statistical measurement with large imaging surveys has traditionally required throwing away a sizable fraction of the data. This is because most measurements have relied on selecting nearly complete samples, where variations in the composition of the galaxy population with seeing, depth, or other survey characteristics are small. We introduce a new measurement method that aims to minimize this wastage, allowing precision measurement for any class of detectable stars or galaxies. We have implemented our proposal in BALROG, software which embeds fake objects in real imaging to accurately characterize measurement biases. We demonstrate this technique with an angular clustering measurement using Dark Energy Survey (DES) data. We first show that recovery of our injected galaxies depends on a variety of survey characteristics in the same way as the real data. We then construct a flux-limited sample of the faintest galaxies in DES, chosen specifically for their sensitivity to depth and seeing variations. Using the synthetic galaxies as randoms in the Landy-Szalay estimator suppresses the effects of variable survey selection by at least two orders of magnitude. With this correction, our measured angular clustering is found to be in excellent agreement with that of a matched sample from much deeper, higher resolution space-based Cosmological Evolution Survey (COSMOS) imaging; over angular scales of 0.004° < θ < 0.2°, we find a best-fitting scaling amplitude between the DES and COSMOS measurements of 1.00 ± 0.09. We expect this methodology to be broadly useful for extending measurements' statistical reach in a variety of upcoming imaging surveys.

  13. Absolute quantitation of protein posttranslational modification isoform.

    Science.gov (United States)

    Yang, Zhu; Li, Ning

    2015-01-01

    Mass spectrometry has been widely applied in characterization and quantification of proteins from complex biological samples. Because the numbers of absolute amounts of proteins are needed in construction of mathematical models for molecular systems of various biological phenotypes and phenomena, a number of quantitative proteomic methods have been adopted to measure absolute quantities of proteins using mass spectrometry. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with internal peptide standards, i.e., the stable isotope-coded peptide dilution series, which was originated from the field of analytical chemistry, becomes a widely applied method in absolute quantitative proteomics research. This approach provides more and more absolute protein quantitation results of high confidence. As quantitative study of posttranslational modification (PTM) that modulates the biological activity of proteins is crucial for biological science and each isoform may contribute a unique biological function, degradation, and/or subcellular location, the absolute quantitation of protein PTM isoforms has become more relevant to its biological significance. In order to obtain the absolute cellular amount of a PTM isoform of a protein accurately, impacts of protein fractionation, protein enrichment, and proteolytic digestion yield should be taken into consideration and those effects before differentially stable isotope-coded PTM peptide standards are spiked into sample peptides have to be corrected. Assisted with stable isotope-labeled peptide standards, the absolute quantitation of isoforms of posttranslationally modified protein (AQUIP) method takes all these factors into account and determines the absolute amount of a protein PTM isoform from the absolute amount of the protein of interest and the PTM occupancy at the site of the protein. The absolute amount of the protein of interest is inferred by quantifying both the absolute amounts of a few PTM

  14. 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)

  15. Barriers to accurately measuring patients' dietary intake in hospitals using the visual estimation method.

    Science.gov (United States)

    Kawasaki, Yui; Kojima, Yui; Akamatsu, Rie

    2016-10-10

    Purpose Visual estimation, an easy-to-perform technique, is commonly used in hospitals to assess dietary intake in patients. The authors performed a qualitative study where the authors interviewed nurses and dietitians about their perceptions of barriers to accurately measuring patients' dietary intake in hospitals using the visual estimation method. The paper aims to discuss these issues. Design/methodology/approach Ten dietitians and ten clinical nurses responded to 30-minute individual interviews in Tokyo, Japan, in September 2014. Each interview was conducted using a common protocol of open-ended questions focusing on the challenges of the visual estimation method and barriers to accurately measuring patients' dietary intake as part of their routine work. The tape-recorded interviews were transcribed and analyzed based on grounded theory. Findings Five main categories emerged: hospitals, meals, colleagues, raters, and patients. Various individual barriers such as skill, attitude, knowledge, and others that had not been considered in previous studies also emerged. External barriers that were out of the raters' control, such as shortage of time, human resources, financial ability, and others, emerged from the "hospitals" category. Research limitations/implications Research participants were all females and many of them had less than ten years of experience. Practical implications In addition to standardizing the visual estimation process, medical staff need to overcome various other internal and external barriers to accurate measurements. Originality/value This is the first study to articulate some important barriers that influence reliability and validity when measuring patients' dietary intake by visual estimation methods in typical clinical settings.

  16. 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.

  17. More accurate systolic blood pressure measurement is required for improved hypertension management: a perspective

    Directory of Open Access Journals (Sweden)

    Nitzan M

    2017-07-01

    Full Text Available Meir Nitzan,1 Itzchak Slotki,2 Linda Shavit2 1Department of Applied Physics/Electro-Optics, Jerusalem College of Technology, 2Department of Nephrology, Shaare Zedek Medical Center, Jerusalem, Israel Abstract: The commonly used techniques for systolic blood pressure (SBP and diastolic blood pressure (DBP measurement are the auscultatory Korotkoff-based sphygmomanometry and oscillometry. The former technique is relatively accurate but is limited to a physician’s office because its automatic variant is subject to noise artifacts. Consequently, the Korotkoff-based measurement overestimates the blood pressure in some patients due to white coat effect, and because it is a single measurement, it cannot properly represent the variable blood pressure. Automatic oscillometry can be used at home by the patient and is preferred even in clinics. However, the technique’s accuracy is low and errors of 10–15 mmHg are common. Recently, we have developed an automatic technique for SBP measurement, based on an arm pressure cuff and a finger photoplethysmographic probe. The technique was found to be significantly more accurate than oscillometry, and comparable to the Korotkoff-based technique, the reference-standard for non-invasive blood pressure measurements. The measurement of SBP is a mainstay for the diagnosis and follow-up of hypertension, which is a major risk factor for several adverse events, mainly cardiovascular. Lowering blood pressure evidently reduces the risk, but excessive lowering can result in hypotension and consequently hypoperfusion to vital organs, since blood pressure is the driving force for blood flow. Erroneous measurement by 10 mmHg can lead to a similar unintended reduction of SBP and may adversely affect patients treated to an SBP of 120–130 mmHg. In particular, in elderly patients, unintended excessive reduction of blood pressure due to inaccurate SBP measurement can result in cerebral hypoperfusion and consequent cognitive

  18. Accurate lung volume measurements in vitro using a novel inert gas washout method suitable for infants.

    Science.gov (United States)

    Shawcross, Anna; Murray, Clare S; Goddard, Nicholas; Gupta, Ruchi; Watson, Stuart; Horsley, Alexander

    2016-05-01

    Multiple breath washout (MBW) in infants presents a number of technical challenges. Conventional MBW is based on simultaneous measurement of flow and gas concentrations. These two signals are aligned and combined to derive expired gas volumes from which lung volumes and measures of ventilation inhomogeneity are calculated. Accuracy of measurement becomes increasingly vulnerable to errors in gas signal alignment at fast respiratory rates. In this paper we describe an alternative method of performing MBW in infants. Expired gas is collected and analyzed to derive functional residual capacity (FRC) and lung clearance index (LCI). This eliminates the need for simultaneous measurement of flow, and integration of flow and gas signals, and significantly reduces deadspace. A highly accurate lung model incorporating BTPS conditions was used to generate realistic infant breathing parameters: FRC of 100-250 mls with respiratory rate of 20-60 min(-1) . In vitro accuracy of FRC measurement using the novel MBW method was assessed using the model. Overall mean error (standard deviation) of FRC measurement was -1.0 (3.3)% with 90% of tests falling within ±5%. FRC measurement using the novel method has superior accuracy in vitro than previously described systems. By uncoupling the measurement of gas volumes from real-time flow and gas measurement, this system offers an alternative method of MBW which is well suited to infants. © 2015 Wiley Periodicals, Inc.

  19. 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.

  20. Cost-effective and accurate method of measuring fetal fraction using SNP imputation.

    Science.gov (United States)

    Kim, Minjeong; Kim, Jai-Hoon; Kim, Kangseok; Kim, Sunshin

    2017-11-08

    With the discovery of cell-free fetal DNA in maternal blood, the demand for non-invasive prenatal testing (NIPT) has been increasing. To obtain reliable NIPT results, it is important to accurately estimate the fetal fraction. In this study, we propose an accurate and cost-effective method for measuring fetal fractions using single-nucleotide polymorphisms (SNPs). A total of 84 samples were sequenced via semiconductor sequencing using a 0.3x sequencing coverage. SNPs were genotyped to estimate the fetal fraction. Approximately 900,000 SNPs were genotyped, and 250,000 of these SNPs matched the semiconductor sequencing results. We performed SNP imputation (1000Genome phase3 and HRC v1.1 reference panel) to increase the number of SNPs. The correlation coefficients (R2) of the fetal fraction estimated using the ratio of non-maternal alleles when coverage was reduced to 0.01 following SNP imputation were 0.93 (HRC v1.1 reference panel) and 0.90 (1000GP3 reference panel). An R2 of 0.72 was found at 0.01x sequencing coverage with no imputation performed. We developed an accurate method to measure fetal fraction using SNP imputation, showing cost-effectiveness by using different commercially available SNP chips and lowering the coverage. We also showed that semiconductor sequencing, which is an inexpensive option, was useful for measuring fetal fraction. python source code and guidelines can be found at https://github.com/KMJ403/fetalfraction-SNPimpute. kangskim@ajou.ac.kr, sunshinkim3@gmail.com. Supplementary data are available at Bioinformatics online.

  1. A temperature compensated dielectric test cell for accurately measuring the complex permittivity of liquids

    Science.gov (United States)

    Risos, Alex; Long, Nicholas; Gouws, Gideon

    2017-10-01

    A measurement of the complex permittivity, ɛr, of a liquid can give valuable information about the molecular polarizability and dielectric losses. This can be obtained by means of an impedance measurement using a parallel plate test cell. However, highly accurate and precise measurements are challenging, in particular when measuring as a function of temperature. Thermal expansion affects the geometry of a test cell and thus the measured capacitance from which ɛr is calculated. In this paper, a broadband four-terminal dielectric test cell is presented that is insensitive to temperature fluctuations. This was achieved by means of a cell geometry exploiting the thermal expansion coefficient of different materials. Experimental measurements on the manufactured cell yielded a stable capacitance of 35.322 ± 0.001 pF across 20 °C-90 °C. The capacitance stayed within ±0.01 pF over multiple experimental cycles of cleaning and assembly. A finite element modeling showed a theoretical accuracy in measuring ɛr better than 99.995%. The measured ɛr values for a number of standard liquids showed an agreement of 99.7% compared to literature values.

  2. Easy Leaf Area: Automated Digital Image Analysis for Rapid and Accurate Measurement of Leaf Area

    Directory of Open Access Journals (Sweden)

    Hsien Ming Easlon

    2014-07-01

    Full Text Available Premise of the study: Measurement of leaf areas from digital photographs has traditionally required significant user input unless backgrounds are carefully masked. Easy Leaf Area was developed to batch process hundreds of Arabidopsis rosette images in minutes, removing background artifacts and saving results to a spreadsheet-ready CSV file. Methods and Results: Easy Leaf Area uses the color ratios of each pixel to distinguish leaves and calibration areas from their background and compares leaf pixel counts to a red calibration area to eliminate the need for camera distance calculations or manual ruler scale measurement that other software methods typically require. Leaf areas estimated by this software from images taken with a camera phone were more accurate than ImageJ estimates from flatbed scanner images. Conclusions: Easy Leaf Area provides an easy-to-use method for rapid measurement of leaf area and nondestructive estimation of canopy area from digital images.

  3. 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°.

  4. 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).

  5. Absolute Summ

    Science.gov (United States)

    Phillips, Alfred, Jr.

    Summ means the entirety of the multiverse. It seems clear, from the inflation theories of A. Guth and others, that the creation of many universes is plausible. We argue that Absolute cosmological ideas, not unlike those of I. Newton, may be consistent with dynamic multiverse creations. As suggested in W. Heisenberg's uncertainty principle, and with the Anthropic Principle defended by S. Hawking, et al., human consciousness, buttressed by findings of neuroscience, may have to be considered in our models. Predictability, as A. Einstein realized with Invariants and General Relativity, may be required for new ideas to be part of physics. We present here a two postulate model geared to an Absolute Summ. The seedbed of this work is part of Akhnaton's philosophy (see S. Freud, Moses and Monotheism). Most important, however, is that the structure of human consciousness, manifest in Kenya's Rift Valley 200,000 years ago as Homo sapiens, who were the culmination of the six million year co-creation process of Hominins and Nature in Africa, allows us to do the physics that we do. .

  6. 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.

  7. Accurate Measurements of Aircraft Engine Soot Emissions Using a CAPS PMssa Monitor

    Science.gov (United States)

    Onasch, Timothy; Thompson, Kevin; Renbaum-Wolff, Lindsay; Smallwood, Greg; Make-Lye, Richard; Freedman, Andrew

    2016-04-01

    We present results of aircraft engine soot emissions measurements during the VARIAnT2 campaign using CAPS PMssa monitors. VARIAnT2, an aircraft engine non-volatile particulate matter (nvPM) emissions field campaign, was focused on understanding the variability in nvPM mass measurements using different measurement techniques and accounting for possible nvPM sampling system losses. The CAPS PMssa monitor accurately measures both the optical extinction and scattering (and thus single scattering albedo and absorption) of an extracted sample using the same sample volume for both measurements with a time resolution of 1 second and sensitivity of better than 1 Mm-1. Absorption is obtained by subtracting the scattering signal from the total extinction. Given that the single scattering albedo of the particulates emitted from the aircraft engine measured at both 630 and 660 nm was on the order of 0.1, any inaccuracy in the scattering measurement has little impact on the accuracy of the ddetermined absorption coefficient. The absorption is converted into nvPM mass using a documented Mass Absorption Coefficient (MAC). Results of soot emission indices (mass soot emitted per mass of fuel consumed) for a turbojet engine as a function of engine power will be presented and compared to results obtained using an EC/OC monitor.

  8. Measuring and managing ratio compression for accurate iTRAQ/TMT quantification.

    Science.gov (United States)

    Savitski, Mikhail M; Mathieson, Toby; Zinn, Nico; Sweetman, Gavain; Doce, Carola; Becher, Isabelle; Pachl, Fiona; Kuster, Bernhard; Bantscheff, Marcus

    2013-08-02

    Isobaric mass tagging (e.g., TMT and iTRAQ) is a precise and sensitive multiplexed peptide/protein quantification technique in mass spectrometry. However, accurate quantification of complex proteomic samples is impaired by cofragmentation of peptides, leading to systematic underestimation of quantitative ratios. Label-free quantification strategies do not suffer from such an accuracy bias but cannot be multiplexed and are less precise. Here, we compared protein quantification results obtained with these methods for a chemoproteomic competition binding experiment and evaluated the utility of measures of spectrum purity in survey spectra for estimating the impact of cofragmentation on measured TMT-ratios. While applying stringent interference filters enables substantially more accurate TMT quantification, this came at the expense of 30%-60% fewer proteins quantified. We devised an algorithm that corrects experimental TMT ratios on the basis of determined peptide interference levels. The quantification accuracy achieved with this correction was comparable to that obtained with stringent spectrum filters but limited the loss in coverage to <10%. The generic applicability of the fold change correction algorithm was further demonstrated by spiking of chemoproteomics samples into excess amounts of E. coli tryptic digests.

  9. 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...

  10. [Preliminary reports of noninvasive accurate method to measure pulmonary vascular capacity in normal volunteers].

    Science.gov (United States)

    Sun, Xing-guo; Mao, Song-shou; Budoff, M J; Stringer, W W; Cheng, Xian-sheng

    2015-07-01

    Because the traditional loop of breathing control and regulation effect on blood circulation, there was rare study of pulmonary vein capacity. We need a noninvasive and accurate pulmonary vascular capacity measurement and analysis method. Twelve normal volunteers were performed a total lung CT scan, image data analysis processing by computer software, the whole lungs from the apex to the base of lung with 40-50 layers by hand-cut, the connection between adjacent layers automatically by a computer simulation, the full pulmonary vascular (≥ 0.6 mm) were treated by high-accuracy three-dimensional imaging technology after removing the interference, and then calculate the whole lung and pulmonary vascular. The whole lung of the 12 normal volunteers from the apex to the base of lung CT scan image layers was 530 ± 98 (range, 431-841). The total capacity of lung and pulmonary vascular blood was 3705 ± 857 (range, 2398-5383) ml, and the total volume of the pulmonary vascular blood was 125 ± 32 (range, 94-201) ml. The pulmonary vein vascular blood volume was 63 ± 16 (range, 47-100) ml. The method of measuring the three-dimensional imaging of pulmonary vascular capacity by analyzing lung CT scan data is available and accurate.

  11. Accurate Measurement of the in vivo Ammonium Concentration in Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Hugo F. Cueto-Rojas

    2016-04-01

    Full Text Available Ammonium (NH4+ is the most common N-source for yeast fermentations, and N-limitation is frequently applied to reduce growth and increase product yields. While there is significant molecular knowledge on NH4+ transport and assimilation, there have been few attempts to measure the in vivo concentration of this metabolite. In this article, we present a sensitive and accurate analytical method to quantify the in vivo intracellular ammonium concentration in Saccharomyces cerevisiae based on standard rapid sampling and metabolomics techniques. The method validation experiments required the development of a proper sample processing protocol to minimize ammonium production/consumption during biomass extraction by assessing the impact of amino acid degradation—an element that is often overlooked. The resulting cold chloroform metabolite extraction method, together with quantification using ultra high performance liquid chromatography-isotope dilution mass spectrometry (UHPLC-IDMS, was not only more sensitive than most of the existing methods but also more accurate than methods that use electrodes, enzymatic reactions, or boiling water or boiling ethanol biomass extraction because it minimized ammonium consumption/production during sampling processing and interference from other metabolites in the quantification of intracellular ammonium. Finally, our validation experiments showed that other metabolites such as pyruvate or 2-oxoglutarate (αKG need to be extracted with cold chloroform to avoid measurements being biased by the degradation of other metabolites (e.g., amino acids.

  12. ACCURATE: Greenhouse Gas Profiles Retrieval from Combined IR-Laser and Microwave Occultation Measurements

    Science.gov (United States)

    Proschek, Veronika; Kirchengast, Gottfried; Schweitzer, Susanne; Fritzer, Johannes

    2010-05-01

    The new climate satellite concept ACCURATE (Atmospheric Climate and Chemistry in the UTLS Region And climate Trends Explorer) enables simultaneous measurement of profiles of greenhouse gases, isotopes, wind and thermodynamic variables from Low Earth Orbit (LEO) satellites. The measurement principle applied is a combination of the novel LEO-LEO infrared laser occultation (LIO) technique and the already better studied LEO-LEO microwave occultation (LMO) technique. Resulting occultation events are evenly distributed around the world, have high vertical resolution and accuracy and are stable over long time periods. The LIO uses near-monochromatic signals in the short-wave infrared range (~2-2.5 μm for ACCURATE). These signals are absorbed by various trace species in the Earth's atmosphere. Profiles of the concentration of the absorbing species can be derived from signal transmission measurements. Accurately known temperature, pressure and humidity profiles derived from simultaneously measured LMO signals are essential pre-information for the retrieval of the trace species profiles. These LMO signals lie in the microwave band region from 17-23 GHz and, optionally, 178-195 GHz. The current ACCURATE mission design is arranged for the measurement of six greenhouse gases (GHG) (H2O, CO2, CH4, N2O, O3, CO) and four isotopes (13CO2, C18OO, HDO, H218O), with focus on the upper troposphere/lower stratosphere region (UTLS, 5-35 km). Wind speed in line-of-sight can be derived from a line-symmetric transmission difference which is caused by wind-induced Doppler shift. By-products are information on cloud layering, aerosol extinction, and scintillation strength. We introduce the methodology to retrieve GHG profiles from quasi-realistic forward-simulated intensities of LIO signals and thermodynamic profiles retrieved in a preceding step from LMO signals. Key of the retrieval methodology is the differencing of two LIO transmission signals, one being GHG sensitive on a target

  13. 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.

  14. A global algorithm for estimating Absolute Salinity

    Directory of Open Access Journals (Sweden)

    T. J. McDougall

    2012-12-01

    Full Text Available The International Thermodynamic Equation of Seawater – 2010 has defined the thermodynamic properties of seawater in terms of a new salinity variable, Absolute Salinity, which takes into account the spatial variation of the composition of seawater. Absolute Salinity more accurately reflects the effects of the dissolved material in seawater on the thermodynamic properties (particularly density than does Practical Salinity.

    When a seawater sample has standard composition (i.e. the ratios of the constituents of sea salt are the same as those of surface water of the North Atlantic, Practical Salinity can be used to accurately evaluate the thermodynamic properties of seawater. When seawater is not of standard composition, Practical Salinity alone is not sufficient and the Absolute Salinity Anomaly needs to be estimated; this anomaly is as large as 0.025 g kg−1 in the northernmost North Pacific. Here we provide an algorithm for estimating Absolute Salinity Anomaly for any location (x, y, p in the world ocean.

    To develop this algorithm, we used the Absolute Salinity Anomaly that is found by comparing the density calculated from Practical Salinity to the density measured in the laboratory. These estimates of Absolute Salinity Anomaly however are limited to the number of available observations (namely 811. In order to provide a practical method that can be used at any location in the world ocean, we take advantage of approximate relationships between Absolute Salinity Anomaly and silicate concentrations (which are available globally.

  15. A solution for measuring accurate reaction time to visual stimuli realized with a programmable microcontroller.

    Science.gov (United States)

    Ohyanagi, Toshio; Sengoku, Yasuhito

    2010-02-01

    This article presents a new solution for measuring accurate reaction time (SMART) to visual stimuli. The SMART is a USB device realized with a Cypress Programmable System-on-Chip (PSoC) mixed-signal array programmable microcontroller. A brief overview of the hardware and firmware of the PSoC is provided, together with the results of three experiments. In Experiment 1, we investigated the timing accuracy of the SMART in measuring reaction time (RT) under different conditions of operating systems (OSs; Windows XP or Vista) and monitor displays (a CRT or an LCD). The results indicated that the timing error in measuring RT by the SMART was less than 2 msec, on average, under all combinations of OS and display and that the SMART was tolerant to jitter and noise. In Experiment 2, we tested the SMART with 8 participants. The results indicated that there was no significant difference among RTs obtained with the SMART under the different conditions of OS and display. In Experiment 3, we used Microsoft (MS) PowerPoint to present visual stimuli on the display. We found no significant difference in RTs obtained using MS DirectX technology versus using the PowerPoint file with the SMART. We are certain that the SMART is a simple and practical solution for measuring RTs accurately. Although there are some restrictions in using the SMART with RT paradigms, the SMART is capable of providing both researchers and health professionals working in clinical settings with new ways of using RT paradigms in their work.

  16. Dial A440 for absolute pitch: absolute pitch memory by non-absolute pitch possessors.

    Science.gov (United States)

    Smith, Nicholas A; Schmuckler, Mark A

    2008-04-01

    Listeners without absolute (or "perfect") pitch have difficulty identifying or producing isolated musical pitches from memory. Instead, they process the relative pattern of pitches, which remains invariant across pitch transposition. Musically untrained non-absolute pitch possessors demonstrated absolute pitch memory for the telephone dial tone, a stimulus that is always heard at the same absolute frequency. Listeners accurately classified pitch-shifted versions of the dial tone as "normal," "higher than normal" or "lower than normal." However, the role of relative pitch processing was also evident, in that listeners' pitch judgments were also sensitive to the frequency range of stimuli.

  17. Absolute measurements of the electronic transition moments of seven band systems of the C2 molecule. Ph.D. Thesis - York Univ., Toronto

    Science.gov (United States)

    Cooper, D. M.

    1979-01-01

    Electronic transition moments of seven C2 singlet and triplet band systems in the 0.2-1.2 micron spectral region were measured. The measurements were made in emission behind incident shock waves in C2H2-argon mixtures. Narrow bandpass radiometers were used to obtain absolute measurements of shock-excited C2 radiation from which absolute electronic transition moments are derived by a synthetic spectrum analysis. New results are reported for the Ballik-Ramsay, Phillips, Swan, Deslandres-d'Azambuja, Fox-Herzberg, Mulliken, and Freymark systems.

  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. 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.

  20. Explicit Knowledge of the Spanish Subjunctive and Accurate Use in Discrete-Point, Oral Production, and Written Production Measures

    National Research Council Canada - National Science Library

    Xavier Gutiérrez

    2017-01-01

    ...). The goal of this study was to examine whether explicit knowledge about the Spanish subjunctive is related to using this structure accurately in discrete-point measures, as well as in measures of oral...

  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. Absolute measurement of cerebral optical coefficients, hemoglobin concentration and oxygen saturation in old and young adults with near-infrared spectroscopy

    Science.gov (United States)

    We present near-infrared spectroscopy measurement of absolute cerebral hemoglobin concentration and saturation in a large sample of 36 healthy elderly (mean age, 85 ± 6 years) and 19 young adults (mean age, 28 ± 4 years). Non-invasive measurements were obtained on the forehead using a commercially a...

  3. Noninvasive MRI measurement of the absolute cerebral blood volume-cerebral blood flow relationship during visual stimulation in healthy humans.

    Science.gov (United States)

    Ciris, Pelin Aksit; Qiu, Maolin; Constable, R Todd

    2014-09-01

    The relationship between cerebral blood volume (CBV) and cerebral blood flow (CBF) underlies blood oxygenation level-dependent functional MRI signal. This study investigates the potential for improved characterization of the CBV-CBF relationship in humans, and examines sex effects as well as spatial variations in the CBV-CBF relationship. Healthy subjects were imaged noninvasively at rest and during visual stimulation, constituting the first MRI measurement of the absolute CBV-CBF relationship in humans with complete coverage of the functional areas of interest. CBV and CBF estimates were consistent with the literature, and their relationship varied both spatially and with sex. In a region of interest with stimulus-induced activation in CBV and CBF at a significance level of the P < 0.05, a power function fit resulted in CBV = 2.1 CBF(0.32) across all subjects, CBV = 0.8 CBF(0.51) in females and CBV = 4.4 CBF(0.15) in males. Exponents decreased in both sexes as ROIs were expanded to include less significantly activated regions. Consideration for potential sex-related differences, as well as regional variations under a range of physiological states, may reconcile some of the variation across literature and advance our understanding of the underlying cerebrovascular physiology. Copyright © 2013 Wiley Periodicals, Inc.

  4. Comparison of a citation-based indicator and peer review for absolute and specific measures of research-group excellence

    CERN Document Server

    Mryglod, O; Holovatch, Yu; Berche, B

    2013-01-01

    Many different measures are used to assess academic research excellence and these are subject to ongoing discussion and debate within the scientometric, university-management and policy-making communities internationally. One topic of continued importance is the extent to which citation-based indicators compare with peer-review-based evaluation. Here we analyse the correlations between values of a particular citation-based impact indicator and peer-review scores in several academic disciplines, from natural to social sciences and humanities. We perform the comparison for research groups rather than for individuals. We make comparisons on two levels. At an absolute level, we compare total impact and overall strength of the group as a whole. At a specific level, we compare academic impact and quality, normalised by the size of the group. We find very high correlations at the former level for some disciplines and poor correlations at the latter level for all disciplines. This means that, although the citation-ba...

  5. Accurate three-dimensional shape and deformation measurement at microscale using digital image correlation

    Science.gov (United States)

    Ren, Maodong; Liang, Jin; Li, Leigang; Wei, Bin; Wang, Lizhong; Tang, Zhengzong

    2015-07-01

    Based on stereomicroscope and three-dimensional (3D) digital image correlation (DIC) method, a non-contact measurement technique is presented to measure the 3D shape and deformation data on miniature specimens and the corresponding microscopic measurement system is developed. A pair of cameras is mounted on a binocular stereo light microscope to acquire pairing micrographs from two different optical paths of a specimen surface spraying with speckle pattern. Considering complex optical paths and high magnification, an accurate equivalent relative calibration method, combining a priori warping functions, is proposed to correct image distortions and optimize the intrinsic and extrinsic parameters of stereomicroscope. Then, a fast one-dimensional synchronous stereo matching method, based on the DIC method and image rectification technique, is proposed to search for discontinuous corresponding points in the pairing micrographs. Finally, the 3D shape is reconstructed from the corresponding points, while the temporal micrographs acquired before and after deformation are employed to determine the full-field deformation. The effectiveness and accuracy of the presented microscale measurement technique are verified by a series of experiments.

  6. Validation study of a fast, accurate, and precise brain tumor volume measurement.

    Science.gov (United States)

    Dang, Mong; Modi, Jayesh; Roberts, Mike; Chan, Christopher; Mitchell, J Ross

    2013-08-01

    Precision and accuracy are sometimes sacrificed to ensure that medical image processing is rapid. To address this, our lab had developed a novel level set segmentation algorithm that is 16× faster and >96% accurate on realistic brain phantoms. This study reports speed, precision and estimated accuracy of our algorithm when measuring MRIs of meningioma brain tumors and compares it to manual tracing and modified MacDonald (MM) ellipsoid criteria. A repeated-measures study allowed us to determine measurement precisions (MPs) - clinically relevant thresholds for statistically significant change. Speed: the level set, MM, and trace methods required 1:20, 1:35, and 9:35 (mm:ss) respectively on average to complete a volume measurement (plesion volumes (p>0.05). Precision: the MM's within-operator and between-operator MPs were significantly higher (worse) than the other methods (p0.05). Our level set is faster on average than MM, yet has accuracy and precision comparable to manual tracing. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  7. Absolute MR thermometry using nanocarriers

    NARCIS (Netherlands)

    Deckers, Roel; Sprinkhuizen, Sara M; Crielaard, Bart J; Ippel, Johannes H; Boelens, Rolf; Bakker, Chris J G; Storm, Gert; Lammers, Twan; Bartels, Lambertus W

    2014-01-01

    Accurate time-resolved temperature mapping is crucial for the safe use of hyperthermia-mediated drug delivery. We here propose a magnetic resonance imaging temperature mapping method in which drug delivery systems serve not only to improve tumor targeting, but also as an accurate and absolute

  8. Measurement of shot noise in magnetic tunnel junction and its utilization for accurate system calibration

    Science.gov (United States)

    Tamaru, S.; Kubota, H.; Yakushiji, K.; Fukushima, A.; Yuasa, S.

    2017-11-01

    This work presents a technique to calibrate the spin torque oscillator (STO) measurement system by utilizing the whiteness of shot noise. The raw shot noise spectrum in a magnetic tunnel junction based STO in the microwave frequency range is obtained by first subtracting the baseline noise, and then excluding the field dependent mag-noise components reflecting the thermally excited spin wave resonances. As the shot noise is guaranteed to be completely white, the total gain of the signal path should be proportional to the shot noise spectrum obtained by the above procedure, which allows for an accurate gain calibration of the system and a quantitative determination of each noise power. The power spectral density of the shot noise as a function of bias voltage obtained by this technique was compared with a theoretical calculation, which showed excellent agreement when the Fano factor was assumed to be 0.99.

  9. A simple and accurate onset detection method for a measured bell-shaped speed profile

    Directory of Open Access Journals (Sweden)

    Lior Botzer

    2009-06-01

    Full Text Available Motor control neuroscientists measure limb trajectories and extract the onset of the movement for a variety of purposes. Such trajectories are often aligned relative to the onset of individual movement before the features of that movement are extracted and their properties are inspected. Onset detection is performed either manually or automatically, typically by selecting a velocity threshold. Here, we present a simple onset detection algorithm that is more accurate than the conventional velocity threshold technique. The proposed method is based on a simple regression and follows the minimum acceleration with constraints model, in which the initial phase of the bell-shaped movement is modeled by a cubic power of the time. We demonstrate the performance of the suggested method and compare it to the velocity threshold technique and to manual onset detection by a group of motor control experts. The database for this comparison consists of simulated minimum jerk trajectories and recorded reaching movements.

  10. Measuring solar reflectance Part I: Defining a metric that accurately predicts solar heat gain

    Energy Technology Data Exchange (ETDEWEB)

    Levinson, Ronnen; Akbari, Hashem; Berdahl, Paul

    2010-05-14

    Solar reflectance can vary with the spectral and angular distributions of incident sunlight, which in turn depend on surface orientation, solar position and atmospheric conditions. A widely used solar reflectance metric based on the ASTM Standard E891 beam-normal solar spectral irradiance underestimates the solar heat gain of a spectrally selective 'cool colored' surface because this irradiance contains a greater fraction of near-infrared light than typically found in ordinary (unconcentrated) global sunlight. At mainland U.S. latitudes, this metric RE891BN can underestimate the annual peak solar heat gain of a typical roof or pavement (slope {le} 5:12 [23{sup o}]) by as much as 89 W m{sup -2}, and underestimate its peak surface temperature by up to 5 K. Using R{sub E891BN} to characterize roofs in a building energy simulation can exaggerate the economic value N of annual cool-roof net energy savings by as much as 23%. We define clear-sky air mass one global horizontal ('AM1GH') solar reflectance R{sub g,0}, a simple and easily measured property that more accurately predicts solar heat gain. R{sub g,0} predicts the annual peak solar heat gain of a roof or pavement to within 2 W m{sup -2}, and overestimates N by no more than 3%. R{sub g,0} is well suited to rating the solar reflectances of roofs, pavements and walls. We show in Part II that R{sub g,0} can be easily and accurately measured with a pyranometer, a solar spectrophotometer or version 6 of the Solar Spectrum Reflectometer.

  11. Accurate measurements of frontal analysis for the determination of adsorption isotherms in supercritical fluid chromatography.

    Science.gov (United States)

    Kamarei, Fahimeh; Gritti, Fabrice; Guiochon, Georges; Burchell, John

    2014-02-14

    The implementation of the traditional FA method is difficult with classical supercritical fluid chromatography (SFC) instruments. The instrument mixer and other sources of extra-column volumes are large and significantly broaden the fronts of injected plugs, which diminishes the precision and accuracy of the FA method. An SFC instrument was modified to permit more accurate determinations of adsorption isotherm data. The sample, the modifier, and CO2 are separately pumped via small volume connection tubes into a small volume mixer (250μL), where they are mixed into a homogeneous fluid fed to the column. The extra-column volumes and the column hold-up volume were accurately measured at each back pressure from the retention times of tracers. This modified instrument was used to measure the adsorption isotherm of S-naproxen by frontal analysis (FA) on a (R, R)-Whelk-O1 column, using a mixture of methanol (20%, v/v) and CO2 as the mobile phase. Its performance is studied at several different back pressures from 100 to 210bar. In all the experiments, the total flow rate was kept to a low value (1mL/min) in order to minimize the variation of the equilibrium constant along the column. Although a suitable breakthrough curve could not be obtained at low back pressures (150bar), conditions remote from the critical point and breakthrough curves with very sharp front shocks are obtained. The RSDs of the profiles recorded at each back pressures are excellent, better than 1%. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Skinfold anthropometry--the accurate method for fat free mass measurement in COPD.

    Science.gov (United States)

    Hronek, Miloslav; Kovarik, Miroslav; Aimova, Petra; Koblizek, Vladimir; Pavlikova, Ladislava; Salajka, Frantisek; Zadak, Zdenek

    2013-10-01

    Fat free mass index (FFMI) is an independent predictor of metabolic and functional consequences in COPD. For its measurement dual energy X-ray absorptiometry (DEXA), skin-fold anthropometry (SFA), bioelectrical impedance analysis (BIA) and bioimpedance spectroscopy (BIS) are used in clinical practice. The aim of our pilot study was to analyse precisely and critically which method is most accurate and available for common use in clinical practice for measurement of FFM by assessment against relevant DEXA in patients with COPD. This was an observational cross-sectional study of consecutive COPD subjects. FFM by methods of SFA, two versions of BIA, and BIS was compared with that from clinically relevant DEXA in 41 outpatients (mean age 66.5 ± 7.7 yrs) with stable COPD, 34 men and 7 women, with mean BMI 28.2 ± 6.1 kg.m(-2). All methods underestimate FFM in comparison with DEXA. In the general evaluation non-significant differences with the smallest mean bias were demonstrated for SFA (1.2 kg) and BIA (3.8 kg), but there was a difference of more than 9 kg using BIS and BIA COPD methods (p DEXA and SFA was demonstrated via Lin's concordance coefficient and Bland-Altman test. SFA has been demonstrated as an accurate, available and cheap method for determination of FFM and FM with application of the Durnin Womersley equation for body density and with the Siri equation for FM in patients with COPD. SFA can be easily applied in routine clinical practice.

  13. Root resistance to cavitation is accurately measured using a centrifuge technique.

    Science.gov (United States)

    Pratt, R B; MacKinnon, E D; Venturas, M D; Crous, C J; Jacobsen, A L

    2015-02-01

    Plants transport water under negative pressure and this makes their xylem vulnerable to cavitation. Among plant organs, root xylem is often highly vulnerable to cavitation due to water stress. The use of centrifuge methods to study organs, such as roots, that have long vessels are hypothesized to produce erroneous estimates of cavitation resistance due to the presence of open vessels through measured samples. The assumption that roots have long vessels may be premature since data for root vessel length are sparse; moreover, recent studies have not supported the existence of a long-vessel artifact for stems when a standard centrifuge technique was used. We examined resistance to cavitation estimated using a standard centrifuge technique and compared these values with native embolism measurements for roots of seven woody species grown in a common garden. For one species we also measured vulnerability using single-vessel air injection. We found excellent agreement between root native embolism and the levels of embolism measured using a centrifuge technique, and with air-seeding estimates from single-vessel injection. Estimates of cavitation resistance measured from centrifuge curves were biologically meaningful and were correlated with field minimum water potentials, vessel diameter (VD), maximum xylem-specific conductivity (Ksmax) and vessel length. Roots did not have unusually long vessels compared with stems; moreover, root vessel length was not correlated to VD or to the vessel length of stems. These results suggest that root cavitation resistance can be accurately and efficiently measured using a standard centrifuge method and that roots are highly vulnerable to cavitation. The role of root cavitation resistance in determining drought tolerance of woody species deserves further study, particularly in the context of climate change. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. 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.

  15. Accurate measurement and influence on device reliability of defect density of a light-emitting diode

    Science.gov (United States)

    Guo, Zu-Qiang; Qian, Ke-Yuan

    2013-10-01

    A method of accurately measuring the defect density of a high-power light-emitting diode (LED) is proposed. The method is based on measuring the number of emitting photons in the magnitude of 105 under the injection current as weak as nA and calculating the non-radiative recombination coefficient which is related to defect density. Defect density is obtained with the self-developed measurement system, and it is demonstrated that defect density has an important influence on LED optical properties like luminous flux and internal quantum efficiency (IQE). At the same time, a batch of GaN-based LEDs with the chip size of 1 mm × 1 mm are selected to conduct the accelerated aging tests lasting for 1000 hours. The results show that defect density exhibits a greater variation and is more sensitive to LED reliability than luminous flux during aging tests. Based on these results, it is concluded that for the GaN-based LED with a chip size of 1mm × 1mm, if its defect density is over 1017/cm3, the LED device performance suffers a serious deterioration, and finally fails.

  16. 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)

  17. Matrix Effects in Proficiency Testing Materials Influence the Accurate Measurement of Gamma-Glutamyltransferase Activity.

    Science.gov (United States)

    Li, Yun; Wang, Jianbing; Huang, Xianzhang; Zeng, Ruili; Zhang, Qiaoxuan; Lin, Haibiao; Han, Liqiao; Ke, Peifeng; Zhuang, Junhua

    2016-10-01

    A consensus on an accurate method to measure γ-glutamyltransferase (GGT) activity for clinical purposes has not been achieved among practicing clinical laboratories. To improve analytical trueness, we evaluated the influences of matrix effects in proficiency testing (PT) materials on the measurement of GGT activity in human serum samples. Five fresh frozen human samples (FFS1-5) and five lyophilized proficiency testing materials (Lyo1-5) were distributed to 23 participating clinical laboratories for the measurement of GGT activity. Target GGT activity values for the samples were obtained by using previously approved reference methods. The results obtained by the Beckman Coulter Unicel DxC 800 Synchron analyzer were compared to the target values assigned by two reference laboratories, and the commutability of the lyophilized materials was evaluated according to Clinical and Laboratory Standards Institute (CLSI) guideline EP14-A2. The relative bias between the results obtained by the Beckman Coulter analyzer and the reference target values ranged from -27.2% to -18.0% for FFS1-5 and from 9.1% to 2.5% for Lyo1-5. Non-commutability of all lyophilized samples falling outside of the 95% prediction interval was observed. The results obtained for the lyophilized PT materials were deemed acceptable within the total allowable errors, suggesting that matrix effects may impart a false sense of confidence that clinical analytical systems are performing very well. A primary reference measurement procedure on fresh frozen serum provides a valuable method for evaluating the trueness of results measured by PT.

  18. A fast method based on NESTA to accurately reconstruct CT image from highly undersampled projection measurements.

    Science.gov (United States)

    He, Zhijie; Qiao, Quanbang; Li, Jun; Huang, Meiping; Zhu, Shouping; Huang, Liyu

    2016-11-22

    The CT image reconstruction algorithm based compressed sensing (CS) can be formulated as an optimization problem that minimizes the total-variation (TV) term constrained by the data fidelity and image nonnegativity. There are a lot of solutions to this problem, but the computational efficiency and reconstructed image quality of these methods still need to be improved. To investigate a faster and more accurate mathematical algorithm to settle TV term minimization problem of CT image reconstruction. A Nesterov's algorithm (NESTA) is a fast and accurate algorithm for solving TV minimization problem, which can be ascribed to the use of most notably Nesterov's smoothing technique and a subtle averaging of sequences of iterates, which has been shown to improve the convergence properties of standard gradient-descent algorithms. In order to demonstrate the superior performance of NESTA on computational efficiency and image quality, a comparison with Simultaneous Algebraic Reconstruction Technique-TV (SART-TV) and Split-Bregman (SpBr) algorithm is made using a digital phantom study and two physical phantom studies from highly undersampled projection measurements. With only 25% of conventional full-scan dose and, NESTA method reduces the average CT number error from 51.76HU to 9.98HU on Shepp-Logan phantom and reduces the average CT number error from 50.13HU to 0.32HU on Catphan 600 phantom. On an anthropomorphic head phantom, the average CT number error is reduced from 84.21HU to 1.01HU in the central uniform area. To the best of our knowledge this is the first work that apply the NESTA method into CT reconstruction based CS. Research shows that this method is of great potential, further studies and optimization are necessary.

  19. Galinstan thermometer is more accurate than digital for the measurement of body temperature in children.

    Science.gov (United States)

    Schreiber, Silvana; Minute, Marta; Tornese, Gianluca; Giorgi, Rita; Duranti, Marina; Ronfani, Luca; Barbi, Egidio

    2013-02-01

    The mercury thermometer (MT) was considered the reference standard for the evaluation of body temperature; however, since April 2009, it has no longer been available in Italy. This study aimed to evaluate the accuracy of digital thermometer (DT) and galinstan thermometer (GT) in comparison with the MT. We prospectively recruited 284 children (age, 1 month to 17 years; mean, 8.5 years) seen in the emergency department of a tertiary pediatric hospital between November and December 2010. For each patient, body temperature was measured sequentially in the right axilla in a randomized fashion using DT, GT, and MT. Fever was defined as an axillary temperature of 37.5°C or greater. The temperature readings with DT and GT were compared statistically with those of MT (reference standard). No statistically significant difference in mean temperature was found between MT and GT in pairwise comparison (P = 0.06), whereas significant differences were found between MT and DT (P temperature of 39°C or higher, the false-negative rate was 65.4% with DT and 30.8% with GT. Although both DT and GT had good specificity and positive predictive value compared with MT, GT had higher sensitivity and a lower rate of false-negative rates. Galinstan thermometer is more accurate in the measurement of body temperature compared with DT or MT.

  20. An Accurate Non-Cooperative Method for Measuring Textureless Spherical Target Based on Calibrated Lasers

    Directory of Open Access Journals (Sweden)

    Fei Wang

    2016-12-01

    Full Text Available Strong demands for accurate non-cooperative target measurement have been arising recently for the tasks of assembling and capturing. Spherical objects are one of the most common targets in these applications. However, the performance of the traditional vision-based reconstruction method was limited for practical use when handling poorly-textured targets. In this paper, we propose a novel multi-sensor fusion system for measuring and reconstructing textureless non-cooperative spherical targets. Our system consists of four simple lasers and a visual camera. This paper presents a complete framework of estimating the geometric parameters of textureless spherical targets: (1 an approach to calibrate the extrinsic parameters between a camera and simple lasers; and (2 a method to reconstruct the 3D position of the laser spots on the target surface and achieve the refined results via an optimized scheme. The experiment results show that our proposed calibration method can obtain a fine calibration result, which is comparable to the state-of-the-art LRF-based methods, and our calibrated system can estimate the geometric parameters with high accuracy in real time.

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

    Energy Technology Data Exchange (ETDEWEB)

    Poullain, Gilles, E-mail: gilles.poullain@ensicaen.fr; More-Chevalier, Joris; Cibert, Christophe; Bouregba, Rachid

    2017-01-15

    Tb{sub x}Dy{sub 1−x}Fe{sub 2}/Pt/Pb(Zr{sub x}, Ti{sub 1−x})O{sub 3} thin films were grown on Pt/TiO{sub 2}/SiO{sub 2}/Si substrate by multi-target sputtering. The magnetoelectric voltage coefficient α{sup Η}{sub ΜΕ} 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 α{sup Η}{sub ΜΕ} 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. - Highlights: • Magnetoelectric device behaves as a voltage source. • A simple way to subtract eddy currents during the measurement, is proposed.

  2. Accurately measuring volume of soil samples using low cost Kinect 3D scanner

    Science.gov (United States)

    van der Sterre, Boy-Santhos; Hut, Rolf; van de Giesen, Nick

    2013-04-01

    The 3D scanner of the Kinect game controller can be used to increase the accuracy and efficiency of determining in situ soil moisture content. Soil moisture is one of the principal hydrological variables in both the water and energy interactions between soil and atmosphere. Current in situ measurements of soil moisture either rely on indirect measurements (of electromagnetic constants or heat capacity) or on physically taking a sample and weighing it in a lab. The bottleneck in accurately retrieving soil moisture using samples is the determining of the volume of the sample. Currently this is mostly done by the very time consuming "sand cone method" in which the volume were the sample used to sit is filled with sand. We show that 3D scanner that is part of the 150 game controller extension "Kinect" can be used to make 3D scans before and after taking the sample. The accuracy of this method is tested by scanning forms of known volume. This method is less time consuming and less error-prone than using a sand cone.

  3. Accurate quantification of glass-forming ability by measuring effective volume relaxation of supercooled melt

    Science.gov (United States)

    Ryu, C. W.; Kang, D. H.; Jeon, S.; Lee, G. W.; Park, E. S.

    2017-10-01

    Herein, we elucidate how to accurately quantify glass-forming ability (GFA) by measuring effective volume relaxation of supercooled melt. We propose a new parameter, denoted as κ, for representing the relaxation, which is calculated by combining temperature-dependent changes of normalized specific volume reflecting relative volume relaxation with the normalized temperature range reflecting the relative position of the C curve in a Time-Temperature-Transformation (TTT) diagram. The interrelationship between the κ parameter and critical cooling rate is elaborated by measuring V-T diagrams and TTT diagrams of Zr55Co26Al19 and Zr46Cu30.14Al8Ag8.36Be7.5 glass-forming alloys and discussed in comparison with representative GFA parameters reported up to date. These results would give us a guideline on how to precisely evaluate GFA by linking volumetric aspect to thermodynamic and kinetic aspects for glass formation and help develop customized glass-forming alloys as well as a highly precise control of glass formation process.

  4. Absolute cross section measurements for the scattering of low- and intermediate-energy electrons from PF3. I. Elastic scattering

    Science.gov (United States)

    Hishiyama, N.; Hoshino, M.; Blanco, F.; García, G.; Tanaka, H.

    2017-12-01

    We report absolute elastic differential cross sections (DCSs) for electron collisions with phosphorus trifluoride, PF3, molecules (e- + PF3) in the impact energy range of 2.0-200 eV and over a scattering angle range of 10°-150°. Measured angular distributions of scattered electron intensities were normalized by reference to the elastic DCSs of He. Corresponding integral and momentum-transfer cross sections were derived by extrapolating the angular range from 0° to 180° with the help of a modified phase-shift analysis. In addition, due to the large dipole moment of the considered molecule, the dipole-Born correction for the forward scattering angles has also been applied. As a part of this study, independent atom model calculations in combination with screening corrected additivity rule were also performed for elastic and inelastic (electronic excitation plus ionization) scattering using a complex optical potential method. Rotational excitation cross sections have been estimated with a dipole-Born approximation procedure. Vibrational excitations are not considered in this calculation. Theoretical data, at the differential and integral levels, were found to reasonably agree with the present experimental results. Furthermore, we explore the systematics of the elastic DCSs for the four-atomic trifluoride molecules of XF3 (X = B, N, and P) and central P-atom in PF3, showing that, owing to the comparatively small effect of the F-atoms, the present angular distributions of elastic DCSs are essentially dominated by the characteristic of the central P-atom at lower impact energies. Finally, these quantitative results for e- - PF3 collisions were compiled together with the previous data available in the literature in order to obtain a cross section dataset for modeling purposes. To comprehensively describe such a considerable amount of data, we proceed by first discussing, in this paper, the vibrationally elastic scattering processes whereas vibrational and electronic

  5. Quantitatively accurate activity measurements with a dedicated cardiac SPECT camera: Physical phantom experiments

    Energy Technology Data Exchange (ETDEWEB)

    Pourmoghaddas, Amir, E-mail: apour@ottawaheart.ca; Wells, R. Glenn [Physics Department, Carleton University, Ottawa, Ontario K1S 5B6, Canada and Cardiology, The University of Ottawa Heart Institute, Ottawa, Ontario K1Y4W7 (Canada)

    2016-01-15

    Healthcare), followed by a CT scan for attenuation correction (AC). For each experiment, separate images were created including reconstruction with no corrections (NC), with AC, with attenuation and dual-energy window (DEW) scatter correction (ACSC), with attenuation and partial volume correction (PVC) applied (ACPVC), and with attenuation, scatter, and PVC applied (ACSCPVC). The DEW SC method used was modified to account for the presence of the low-energy tail. Results: T-tests showed that the mean error in absolute activity measurement was reduced significantly for AC and ACSC compared to NC for both (hot and cold) datasets (p < 0.001) and that ACSC, ACPVC, and ACSCPVC show significant reductions in mean differences compared to AC (p ≤ 0.001) without increasing the uncertainty (p > 0.4). The effect of SC and PVC was significant in reducing errors over AC in both datasets (p < 0.001 and p < 0.01, respectively), resulting in a mean error of 5% ± 4%. Conclusions: Quantitative measurements of cardiac {sup 99m}Tc activity are achievable using attenuation and scatter corrections, with the authors’ dedicated cardiac SPECT camera. Partial volume corrections offer improvements in measurement accuracy in AC images and ACSC images with elevated background activity; however, these improvements are not significant in ACSC images with low background activity.

  6. Accurate optical measurement of nuclear polarization in optically pumped ^3He gas

    Science.gov (United States)

    Bigelow, N. P.; Nacher, P. J.; Leduc, M.

    1992-12-01

    Large nuclear polarizations M (over 80 %) can now be achieved in gaseous ^3He by optical pumping. The gas is excited by an RF discharge and is oriented using a high power LNA laser which is lamp pumped and tuned to the 2 ^3S-2 ^3P transition at 1.08 μm. In this paper we describe an experiment in which we measure M with high absolute precision. Our method is based on a change as a function of M in the ratio of σ or π polarized light absorbed from a weak probe beam by the 2 ^3S metastable atoms. The probe was delivered by a diode pumped LNA laser and propagated perpendicular to the direction of the magnetization. Simultaneous measurement of M was made by monitoring the degree of circular polarization \\cal{P} of the optical line at 668 nm emitted by the discharge. Our measurements show a linear relationship between M and \\cal{P} for all accessible M values and for a wide range of experimental conditions (sample pressure, magnetic field, RF discharge level, etc.). This provides a second method of measurement of the ^3He nuclear polarization which is simple to operate and is calibrated and is calibrated over a pressure range of 0.15 to 6.5 torr. On peut maintenant produire par pompage optique de fortes polarisations nucléaires M (M supérieure à 80 % dans l' ^3He gazeux. Le gaz est excité par une décharge radiofréquence et orienté à l'aide d'un laser LNA de forte intensité qui est pompé par des lampes et accordé sur la transition 2 ^3S-2 ^3P à 1,08 μm. Dans cet article, nous décrivons une expérience où nous mesurons M avec une grande précision absolue. Notre méthode est fondée sur la variation en fonction de M de l'absorption par les atomes métastables d'un faisceau sonde de faible intensité polarisé linéairement. Nous mesurons le rapport des absorptions pour des polarisations π et σ. Le faisceau sonde est un laser LNA pompé par diode qui se propage perpendiculairement à la direction de l'aimantation. Simultanément, nous mesurons M par le

  7. 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.

  8. 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.

  9. Absolute cerebral blood flow and blood volume measured by magnetic resonance imaging bolus tracking: comparison with positron emission tomography values

    DEFF Research Database (Denmark)

    Østergaard, Leif; Smith, D F; Vestergaard-Poulsen, Peter

    1998-01-01

    blood volume (CBV) estimates obtained using this normalization constant correlated well with values obtained by O-15 labeled carbonmonooxide (C15O) PET. However, PET CBV values were approximately 2.5 times larger than absolute MRI CBV values, supporting the hypothesized sensitivity of MRI to small...

  10. Measurement of absolute yields of lyman transitions in pionic hydrogen and deuterium as a function of pressure

    Energy Technology Data Exchange (ETDEWEB)

    Rusi El Hassani, A.J. [Eidgenoessische Technische Hochschule, Villigen (Switzerland). Inst. fuer Teilchenphysik; Beer, W. [Eidgenoessische Technische Hochschule, Villigen (Switzerland). Inst. fuer Teilchenphysik; Gilot, J.F. [Eidgenoessische Technische Hochschule, Villigen (Switzerland). Inst. fuer Teilchenphysik; Goudsmit, P.F.A. [Eidgenoessische Technische Hochschule, Villigen (Switzerland). Inst. fuer Teilchenphysik; Leisi, H.J. [Eidgenoessische Technische Hochschule, Villigen (Switzerland). Inst. fuer Teilchenphysik; Thomann, S. [Eidgenoessische Technische Hochschule, Villigen (Switzerland). Inst. fuer Teilchenphysik; Volken, W. [Eidgenoessische Technische Hochschule, Villigen (Switzerland). Inst. fuer Teilchenphysik; Aschenauer, E.C. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Gabathuler, K. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Simons, L.M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Bovet, E. [Neuchatel Univ. (Switzerland). Inst. de Physique; Egger, J.P. [Neuchatel Univ. (Switzerland). Inst. de Physique; Fiorucci, G. [Neuchatel Univ. (Switzerland). Inst. de Physique; Markushin, V.E. [Kurchatov Inst. (RKI), Moscow (Russian Federation)

    1995-02-01

    Absolute yields of K X-ray transitions in pionic hydrogen and deuterium were determined with accuracies of typically {+-}10% at target pressures of 2.8, 15 and 40 bar and compared with the results of a recently developed cascade code. (orig.)

  11. Measuring sparse temporal-variation for accurate registration of dynamic contrast-enhanced breast MR images.

    Science.gov (United States)

    Zheng, Yuanjie; Wei, Benzheng; Liu, Hui; Xiao, Rui; Gee, James C

    2015-12-01

    Accurate registration of dynamic contrast-enhanced (DCE) MR breast images is challenging due to the temporal variations of image intensity and the non-rigidity of breast motion. The former can cause the well-known tumor shrinking/expanding problem in registration process while the latter complicates the task by requiring an estimation of non-rigid deformation. In this paper, we treat the intensity's temporal variations as "corruptions" which spatially distribute in a sparse pattern and model them with a L1 norm and a Lorentzian norm. We show that these new image similarity measurements can characterize the non-Gaussian property of the difference between the pre-contrast and post-contrast images and help to resolve the shrinking/expanding problem by forgiving significant image variations. Furthermore, we propose an iteratively re-weighted least squares based method and a linear programming based technique for optimizing the objective functions obtained using these two novel norms. We show that these optimization techniques outperform the traditional gradient-descent approach. Experimental results with sequential DCE-MR images from 28 patients show the superior performances of our algorithms. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Accurate measurement of the localization properties of electric transmission lines using the overlap amplitude

    Science.gov (United States)

    Lazo, Edmundo

    2017-06-01

    We determine the localization properties of classic direct electric transmission lines by means of the overlap amplitude. The amplitude is defined as C i,j ω = 2| I i ω I j ω |, where I i ω is the electric current in the ith cell of the transmission line for the state with frequency ω. This definition is motivated by the concurrence C i,j α = 2| φ i α φ j α |, which is a quantum correlation measure (pairwise entanglement). We distribute the inductances L j according to three non-linear models: (a) the slowly varying potential model; (b) the Aubry-André model and (c) the Soukoulis-Economou model. The results show that the average of the powers of the overlap amplitude ⟨( C i,j ω )2 q ⟩ and its scaling properties may accurately characterize the localization behavior of these non-linear models. Moreover, the overlap amplitude can be used to determine the mobility edge of some non-periodic models.

  13. ESR isochron exercises: how accurately do modern dose rate measurements reflect paleodose rates?

    Science.gov (United States)

    Blackwell, B. A. B.; Skinner, A. R.; Blickstein, J. I. B.

    2001-12-01

    In electron spin resonance (ESR) dating tooth enamel, after selecting the appropriate U uptake model, the most significant uncertainty lies in the external dose rate, Dext( t), which can vary with time. Unlike standard ESR which measures the external dose rate in the modern context, Dext( t0), assuming that it reflects the actual external dose rate over the millennia, the isochron method calculates the time-averaged dose rate, D¯ext(t) , experienced by the tooth without such assumptions. In 45 teeth ranging from 30 ka to 4.5 Ma from 17 sites, D¯ext(t) determined by EU or LU isochrons only equalled Dext( t0) about 50% of the time. In several sites, geologic evidence indicates that secondary sedimentary processes have significantly altered sedimentary compositions and/or water concentrations, and hence, Dext( t), over time, accounting for 60-80% of D¯ext(t)-D ext(t 0) disagreements. Simulated isochrons suggest that at least seven teeth, whose isochrons had negative ages or D¯ext(t) , probably had lost U, while five, with accurate ages but very large D¯ext(t) , have likely experienced a second U uptake event.

  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 concentration measurements using surface-enhanced Raman and deuterium exchanged dye pairs.

    Science.gov (United States)

    Deb, Shirshendu K; Davis, Brandon; Ben-Amotz, Dor; Davisson, V Jo

    2008-09-01

    Quantitative applications of surface-enhanced resonance Raman scattering (SERRS) are often limited by the reproducibility of SERRS intensities, given the difficulty of controlling analyte-substrate interactions and the associated local field enhancement. As demonstrated here, SERRS from dye molecules even within the same structural class that compete with similar substrates display distinct spectral intensities that are not proportional to analyte concentrations, which limits their use as internal standardization probes and/or for multiplex analysis. Recently, we demonstrated that isotopic variants of rhodamine 6G (R6G), namely R6G-d0 and R6G-d4, can be used for internal standards in SERRS experiments with a linear optical response from picomolar to micromolar concentrations (of total analytes). Here we extend these results by describing a straightforward method for obtaining isotopomeric pairs of other Raman active dyes by hydrogen-deuterium exchange conditions for substitution at electron rich aromatic heterocycles. Most of the known SERRS active probes can be converted into the corresponding isotopomeric molecule by this exchange method, which significantly expands the scope of the isotopic edited internal standard (IEIS) approach. The relative quantification using IEIS enables accurate, reproducible (residual standard deviation+/-2.2%) concentration measurements over a range of 200 pM to 2 microM. These studies enable easy access to a variety of isotopically substituted Raman active dyes and establish the generality of the methodology for quantitative SERRS measurements. For the first time, three rhodamine 6G isotopomers have been created and show distinct Raman spectra, demonstrating the principle of the approach for application as a multiplex technique in biomolecular detection/quantification.

  16. Accurate measurements of {sup 210}Pb in industrial wastes for environmental radiation risk assessment purpose

    Energy Technology Data Exchange (ETDEWEB)

    Bonczyk, Michal; Michalik, Boguslaw [Central Mining Institute, Silesian Centre for Environmental Radioactivity, Plac Gwarkow 1, 40-166 Katowice (Poland)

    2014-07-01

    Lead {sup 210}Pb is a naturally occurring radioactive nuclide element of the uranium ({sup 238}U) radioactive series. It is produced as a result of the decay of so-called short-lived progenies of {sup 222}Rn, i.e. {sup 214}Po (99.98%) and {sup 214}Bi by {sup 219}Tl (0.02%). Activity concentration of lead {sup 210}Pb could vary independently from parent radionuclides due to its physical and chemical properties, especially, due to its half-life (T{sub 1/2} = 22,3 years). Hence, its behaviour in natural environment is very complex and difficult in forecasting. Lead {sup 210}Pb in substantial amount occurs in mining, gas and oil extraction industry wastes, which are deposited in natural environment very often. Due to lack of secular equilibrium proper radiation risk assessment requires accurate concentration of {sup 210}Pb in such materials. The laboratory measurements seem to be the only reliable method in environmental radioactivity monitoring. One of the methods is gamma-ray spectrometry, which is very fast and cost-effective method to determine {sup 210}Pb concentration. On the other hand, the self-attenuation of gamma ray from {sup 210}Pb (46,5 keV) is significant and not depends only on sample density as well the chemical composition (sample matrix) is crucial. Current work describes how the self-attenuation correction factors in the case of {sup 210}Pb concentration analysis in mining wastes are important when environmental radiation risk assessment is carried out. The measurements were done for such industrial wastes as mine sediments which contain significant amount of elements with high Z-number (Barium, Lead, etc.) Experimentally obtained correction factors range between 0.51-6.96 cm{sup 2}/g. Neglecting this factor can cause a significant error or underestimations in radiological risk assessment. (authors)

  17. Progress Report on Accurate Measurement of Dynamic Topography in the Oceanic and Continental Realms

    Science.gov (United States)

    White, N. J.

    2012-12-01

    Convective circulation of the Earth's mantle maintains plate motion but we know little about the spatial and temporal details of this circulation. Accurate maps of the spatial and temporal pattern of dynamic topography should profoundly affect our understanding the the relationship between surface geology and deep Earth processes. The major difficulty is the `tyranny of isostasy'. In other words, dynamic topography is difficult to measure because crustal and lithospheric thickness and density changes are the dominant control of surface elevation. Some progress can be made along continental margins by measuring residual depth anomalies of the oldest oceanic floor on newly available seismic reflection and wide-angle profiles. These estimates of dynamic topography have amplitudes of ± 1 km and wavelengths of 102--104 km. They mostly, but not always, correlate with long wavelength free-air gravity anomalies, although correlation with seismic tomographic images is poorer. The distribution of dynamic topography throughout the rest of the oceanic realm can be supplemented by using ship-track data in regions with sparse sedimentary cover and by exploiting the mid-oceanic ridge system. On the continents, it is more difficult to measure dynamic topography with the same accuracy since the density structure of continental lithosphere is so variable but progress can be made on three fronts. First, long-wavelength gravity anomalies which straddle continental margins are an obvious and important guide. Secondly, stratal geometries across continental shelves contain information about positive and negative surface elevation changes, provided sea-level variation is known. In several cases, well-calibrated seismic surveys can be used to constrain spatial and temporal patterns of dynamic topography. Our results suggest that dynamic topography can rapidly change on short wavelengths. Finally, drainage networks appear to contain information about the spatial and temporal patterns of

  18. Normal incidence spectrophotometer using high density transmission grating technology and highly efficiency silicon photodiodes for absolute solar EUV irradiance measurements

    Science.gov (United States)

    Ogawa, H. S.; Mcmullin, D.; Judge, D. L.; Korde, R.

    1992-01-01

    New developments in transmission grating and photodiode technology now make it possible to realize spectrometers in the extreme ultraviolet (EUV) spectral region (wavelengths less than 1000 A) which are expected to be virtually constant in their diffraction and detector properties. Time dependent effects associated with reflection gratings are eliminated through the use of free standing transmission gratings. These gratings together with recently developed and highly stable EUV photodiodes have been utilized to construct a highly stable normal incidence spectrophotometer to monitor the variability and absolute intensity of the solar 304 A line. Owing to its low weight and compactness, such a spectrometer will be a valuable tool for providing absolute solar irradiance throughout the EUV. This novel instrument will also be useful for cross-calibrating other EUV flight instruments and will be flown on a series of Hitchhiker Shuttle Flights and on SOHO. A preliminary version of this instrument has been fabricated and characterized, and the results are described.

  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

    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. 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. 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. 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. 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 accurately reflect core body temperature, probably because it is

  20. 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

  1. Absolute measurement of subnanometer scale vibration of cochlear partition of an excised guinea pig cochlea using spectral-domain phase-sensitive optical coherence tomography

    Science.gov (United States)

    Subhash, Hrebesh M.; Choudhury, Niloy; Jacques, Steven L.; Wang, Ruikang K.; Chen, Fangyi; Zha, Dingjun; Nuttall, Alfred L.

    2012-01-01

    Direct measurement of absolute vibration parameters from different locations within the mammalian organ of Corti is crucial for understanding the hearing mechanics such as how sound propagates through the cochlea and how sound stimulates the vibration of various structures of the cochlea, namely, basilar membrane (BM), recticular lamina, outer hair cells and tectorial membrane (TM). In this study we demonstrate the feasibility a modified phase-sensitive spectral domain optical coherence tomography system to provide subnanometer scale vibration information from multiple angles within the imaging beam. The system has the potential to provide depth resolved absolute vibration measurement of tissue microstructures from each of the delay-encoded vibration images with a noise floor of ~0.3nm at 200Hz.

  2. SI-traceable absolute distance measurement over more than 800 meters with sub-nanometer interferometry by two-color inline refractivity compensation

    Science.gov (United States)

    Meiners-Hagen, Karl; Meyer, Tobias; Mildner, Jutta; Pollinger, Florian

    2017-11-01

    In this work, we demonstrate two-color inline refractivity compensation in a heterodyne synthetic wavelength interferometer for a measurement of absolute distances over several hundred meters with sub-millimeter accuracy. Two frequency-doubled Nd:YAG lasers with a coherence length of more than 1 km are used as light sources. Direct SI traceability is achieved by controlling the lasers' frequency difference in the radio frequency regime. The resulting synthetic wavelengths at 532 nm and 1064 nm are used for the absolute distance measurement and dispersion-based inline refractive index compensation. A standard deviation of 50 μm is achieved for distances up to 864 m. This performance corresponds to a standard deviation of the observable, the difference of the four optical wavelengths, on a sub-nanometer level. Comparison against white light interferometry confirms sub-millimeter accuracy over this distance. Temporally resolved data over 864 m provide quantitative insights into the influence of chromatic beam paths.

  3. 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

  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

    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 essen...

  5. Measurements of the absolute branching fractions for D-s(+) -> eta e(+)nu(e) and D-s(+) -> eta ' e(+)nu(e)

    NARCIS (Netherlands)

    Ablikim, M.; Achasov, M. N.; Ahmed, S.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Bakina, O.; Ferroli, R. Baldini; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Berger, N.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chai, J.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, P. L.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dorjkhaidav, O.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fegan, S.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; He, X. Q.; Heinsius, F. H.; Held, T.; Heng, Y. K.; Holtmann, T.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Y.; Huang, Z. L.; Hussain, T.; Andersson, W. Ikegami; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kupsc, A.; Kuhn, W.; Lange, J. S.; Lara, M.; Larin, P.; Leithoff, H.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. L.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Y. B.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Y. Y.; Liu, Z. A.; Liu, Zhiqing; Loehner, H.; Long, Y. F.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Malik, Q. A.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Mezzadri, G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales, C. Morales; Muchnoi, N. Yu.; Muramatsu, H.; Musiol, P.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, J. J.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Sarantsev, A.; Savrie, M.; Schnier, C.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shi, M.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, Dan; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, W.; Wang, W. P.; Wang, X. F.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z. J.; Xie, Y. G.; Xiong, X. A.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; You, Z. Y.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.

    2016-01-01

    By analyzing 482 pb(-1) of e(+)e(-) collision data collected at root s = 4.009 GeV with the BESIII detector at the BEPCII collider, we measure the absolute branching fractions for the semileptonic decays D-s(+) -> eta e(+)nu(e) and D-s(+) -> eta ' e(+)nu(e) to be B(D-s(+) -> eta e(+)nu(e)) = (2.30

  6. Absolute measurement of {beta} activities and application to the determination of neutronic densities; Mesure absolue d'activites {beta} et application a la determination des densites neutronique

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, R. [Commissariat a l' Energie Atomique, Lab. du Fort de Chatillon, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1951-01-15

    M. Berthelot, to my entrance to the ''Commissariat a l 'Energie Atomique'', proposed me to study the absolute measurement of neutron densities. Very quickly the problem of the absolute activity of {beta} sources became the central object of this work. In a first part, we will develop the methods of absolute determination for {beta} activities. The use of a 4{pi} counter permits to get the absolute activity of all beta radioactive source, susceptible to be put as thin leaf and of period superior than some minutes. The method is independent of the spectra of the measured radioelement. we will describe in the second part some applications which use neutron densities measurement, neutron sources intensities and ratio of cross sections of capture of thermal neutrons. (M.B.) [French] M. Berthelot, a mon entree au ''Commissariat a l 'Energie Atomique'', m'a propose d'etudier la mesure absolue des densites neutroniques. Tres rapidement le probleme de l'activite absolue des sources beta est devenu l'objet central de ce travail. Dans une premiere partie, on abordera les methodes de determination absolue des activites beta. L'utilisation d'un compteur 4{pi} permet d 'obtenir l'activite absolue de toute source radioactive beta, susceptible d'etre mise sous forme de feuille mince et de periode superieure a quelques minutes. La methode est independante du spectre du radioelement mesure. On decrira dans la seconde partie quelques applications a des mesures de densites neutroniques, d'intensites de sources de neutrons et de rapport de sections efficaces de capture de neutrons thermiques. (M.B.)

  7. 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...... includes the particle's shape parameter, known as sphericity. Mass and sphericity are obtained from 3-dimensional data with an industrial X-ray computed tomography (CT) scanner. CT data can be used to accurately determine the volume-basis median of the particles (using the volume-equivalent particle......Accurate particle mass and velocity measurement is needed for interpreting test results in erosion tests of materials and coatings. The impact and damage of a surface is influenced by the kinetic energy of a particle, i.e. particle mass and velocity. Particle mass is usually determined with optical...

  8. 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.

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

    OpenAIRE

    Aculinin A.; Smikov V.

    2008-01-01

    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.

  10. Measurement of the absolute branching ratio of the K+→π+π−π+(γ decay with the KLOE detector

    Directory of Open Access Journals (Sweden)

    D. Babusci

    2014-11-01

    Full Text Available The absolute branching ratio of the K+→π+π−π+(γ decay, inclusive of final-state radiation, has been measured using ∼17 million tagged K+ mesons collected with the KLOE detector at DAΦNE, the Frascati ϕ-factory. The result is:BR(K+→π+π−π+(γ=0.05565±0.00031stat±0.00025syst a factor ≃ 5 more precise with respect to the previous result. This work completes the program of precision measurements of the dominant kaon branching ratios at KLOE.

  11. Measurement of absolute concentrations of individual compounds in metabolite mixtures by gradient-selective time-zero 1H-13C HSQC with two concentration references and fast maximum likelihood reconstruction analysis.

    Science.gov (United States)

    Hu, Kaifeng; Ellinger, James J; Chylla, Roger A; Markley, John L

    2011-12-15

    Time-zero 2D (13)C HSQC (HSQC(0)) spectroscopy offers advantages over traditional 2D NMR for quantitative analysis of solutions containing a mixture of compounds because the signal intensities are directly proportional to the concentrations of the constituents. The HSQC(0) spectrum is derived from a series of spectra collected with increasing repetition times within the basic HSQC block by extrapolating the repetition time to zero. Here we present an alternative approach to data collection, gradient-selective time-zero (1)H-(13)C HSQC(0) in combination with fast maximum likelihood reconstruction (FMLR) data analysis and the use of two concentration references for absolute concentration determination. Gradient-selective data acquisition results in cleaner spectra, and NMR data can be acquired in both constant-time and non-constant-time mode. Semiautomatic data analysis is supported by the FMLR approach, which is used to deconvolute the spectra and extract peak volumes. The peak volumes obtained from this analysis are converted to absolute concentrations by reference to the peak volumes of two internal reference compounds of known concentration: DSS (4,4-dimethyl-4-silapentane-1-sulfonic acid) at the low concentration limit (which also serves as chemical shift reference) and MES (2-(N-morpholino)ethanesulfonic acid) at the high concentration limit. The linear relationship between peak volumes and concentration is better defined with two references than with one, and the measured absolute concentrations of individual compounds in the mixture are more accurate. We compare results from semiautomated gsHSQC(0) with those obtained by the original manual phase-cycled HSQC(0) approach. The new approach is suitable for automatic metabolite profiling by simultaneous quantification of multiple metabolites in a complex mixture.

  12. Measurement of Absolute Concentrations of Individual Compounds in Metabolite Mixtures by Gradient-Selective Time-Zero 1H-13C HSQC (gsHSQC0) with Two Concentration References and Fast Maximum Likelihood Reconstruction Analysis

    Science.gov (United States)

    Hu, Kaifeng; Ellinger, James J.; Chylla, Roger A.; Markley, John L.

    2011-01-01

    Time-zero 2D 13C HSQC (HSQC0) spectroscopy offers advantages over traditional 2D NMR for quantitative analysis of solutions containing a mixture of compounds because the signal intensities are directly proportional to the concentrations of the constituents. The HSQC0 spectrum is derived from a series of spectra collected with increasing repetition times within the basic HSQC block by extrapolating the repetition time to zero. Here we present an alternative approach to data collection, gradient-selective time-zero 1H-13C HSQC0 in combination with fast maximum likelihood reconstruction (FMLR) data analysis and the use of two concentration references for absolute concentration determination. Gradient-selective data acquisition results in cleaner spectra, and NMR data can be acquired in both constant-time and non-constant time mode. Semi-automatic data analysis is supported by the FMLR approach, which is used to deconvolute the spectra and extract peak volumes. The peak volumes obtained from this analysis are converted to absolute concentrations by reference to the peak volumes of two internal reference compounds of known concentration: DSS (4,4-dimethyl-4-silapentane-1-sulfonic acid) at the low concentration limit (which also serves as chemical shift reference) and MES (2-(N-morpholino)ethanesulfonic acid) at the high concentration limit. The linear relationship between peak volumes and concentration is better defined with two references than with one, and the measured absolute concentrations of individual compounds in the mixture are more accurate. We compare results from semi-automated gsHSQC0 with those obtained by the original manual phase-cycled HSQC0 approach. The new approach is suitable for automatic metabolite profiling by simultaneous quantification of multiple metabolites in a complex mixture. PMID:22029275

  13. Reader variability in breast density estimation from full-field digital mammograms: the effect of image postprocessing on relative and absolute measures.

    Science.gov (United States)

    Keller, Brad M; Nathan, Diane L; Gavenonis, Sara C; Chen, Jinbo; Conant, Emily F; Kontos, Despina

    2013-05-01

    Mammographic breast density, a strong risk factor for breast cancer, may be measured as either a relative percentage of dense (ie, radiopaque) breast tissue or as an absolute area from either raw (ie, "for processing") or vendor postprocessed (ie, "for presentation") digital mammograms. Given the increasing interest in the incorporation of mammographic density in breast cancer risk assessment, the purpose of this study is to determine the inherent reader variability in breast density assessment from raw and vendor-processed digital mammograms, because inconsistent estimates could to lead to misclassification of an individual woman's risk for breast cancer. Bilateral, mediolateral-oblique view, raw, and processed digital mammograms of 81 women were retrospectively collected for this study (N = 324 images). Mammographic percent density and absolute dense tissue area estimates for each image were obtained from two radiologists using a validated, interactive software tool. The variability of interreader agreement was not found to be affected by the image presentation style (ie, raw or processed, F-test: P > .5). Interreader estimates of relative and absolute breast density are strongly correlated (Pearson r > 0.84, P present in the breast, indicating the need to use standardized tools to mitigate this effect. Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.

  14. Developing a novel technique for absolute measurements of the principal- and second-shock Hugoniots: a benchmark for the impedance-match methods

    Science.gov (United States)

    Gu, Yunjun; Zheng, Jun; Chen, Qifeng; Li, Chengjun; Li, Jiangtao; Chen, Zhiyun

    2017-06-01

    A novel diagnostics configuration was presented for performing the absolute measurements of the principal- and second-shock Hugoniots of the dense gaseous H2+D2 mixtures under multi-shock compression and probing their thermodynamic properties by a joint diagnostics of multi-channel optical pyrometer (MCOP), Doppler Pin System (DPS), and streak camera. This technique allowed the time-resolved optical radiation histories, interface velocity profiles, and time-resolved spectrum of the multi-compressed sample to be simultaneously measured in a single shot. The shock wave velocities and particle velocities under the former two shock compressions can be directly determined with the help of the above multiple detects instead of the impedance-match methods. So, absolute measurements of the principal- and second-shock Hugoniots for pre-compressed dense gaseous H2+D2 mixtures under multi-shock compression can be achieved, which provides a benchmark for the impedance-match measurement technique. Furthermore, the combination of multiple diagnostics also allows different experimental observables to be cross-checked, which reinforces the reliability of the experimental measurements.

  15. Lightdrum—Portable Light Stage for Accurate BTF Measurement on Site

    Directory of Open Access Journals (Sweden)

    Vlastimil Havran

    2017-02-01

    Full Text Available We propose a miniaturised light stage for measuring the bidirectional reflectance distribution function (BRDF and the bidirectional texture function (BTF of surfaces on site in real world application scenarios. The main principle of our lightweight BTF acquisition gantry is a compact hemispherical skeleton with cameras along the meridian and with light emitting diode (LED modules shining light onto a sample surface. The proposed device is portable and achieves a high speed of measurement while maintaining high degree of accuracy. While the positions of the LEDs are fixed on the hemisphere, the cameras allow us to cover the range of the zenith angle from 0 ∘ to 75 ∘ and by rotating the cameras along the axis of the hemisphere we can cover all possible camera directions. This allows us to take measurements with almost the same quality as existing stationary BTF gantries. Two degrees of freedom can be set arbitrarily for measurements and the other two degrees of freedom are fixed, which provides a tradeoff between accuracy of measurements and practical applicability. Assuming that a measured sample is locally flat and spatially accessible, we can set the correct perpendicular direction against the measured sample by means of an auto-collimator prior to measuring. Further, we have designed and used a marker sticker method to allow for the easy rectification and alignment of acquired images during data processing. We show the results of our approach by images rendered for 36 measured material samples.

  16. Lightdrum—Portable Light Stage for Accurate BTF Measurement on Site

    Science.gov (United States)

    Havran, Vlastimil; Hošek, Jan; Němcová, Šárka; Čáp, Jiří; Bittner, Jiří

    2017-01-01

    We propose a miniaturised light stage for measuring the bidirectional reflectance distribution function (BRDF) and the bidirectional texture function (BTF) of surfaces on site in real world application scenarios. The main principle of our lightweight BTF acquisition gantry is a compact hemispherical skeleton with cameras along the meridian and with light emitting diode (LED) modules shining light onto a sample surface. The proposed device is portable and achieves a high speed of measurement while maintaining high degree of accuracy. While the positions of the LEDs are fixed on the hemisphere, the cameras allow us to cover the range of the zenith angle from 0∘ to 75∘ and by rotating the cameras along the axis of the hemisphere we can cover all possible camera directions. This allows us to take measurements with almost the same quality as existing stationary BTF gantries. Two degrees of freedom can be set arbitrarily for measurements and the other two degrees of freedom are fixed, which provides a tradeoff between accuracy of measurements and practical applicability. Assuming that a measured sample is locally flat and spatially accessible, we can set the correct perpendicular direction against the measured sample by means of an auto-collimator prior to measuring. Further, we have designed and used a marker sticker method to allow for the easy rectification and alignment of acquired images during data processing. We show the results of our approach by images rendered for 36 measured material samples. PMID:28241466

  17. Calibration method for accurate optical measurement of thickness profile for the paper industry

    Science.gov (United States)

    Graeffe, Jussi

    2009-06-01

    Online measurement of paper thickness profile is essential in paper production. For decades paper thickness has been measured online with sensors that are contacting the web on both sides. In 2005 a new optical online paper thickness gauge was introduced which only contacts the web on the other side. The sensor is based on a laser triangulation sensor and a magnetic sensor, and it determines the paper thickness from the difference of the two measurements. For calibration of the two sensors, a robust concept has been developed which utilizes the measured object and takes place in the measuring environment so that the calibration is automatically adjusted to the current measuring circumstances. More importantly, with the presented method the non-linearity of the laser sensor is cancelled enabling the measurement of the thickness profile shape with an accuracy much better than that of the laser sensor. Profile accuracy of 0.5 μm (2σ) has become normal while the measuring range is often several hundreds of microns and the measuring distance to the paper web 1.0-1.5 mm with a laser sensor having linearity of +/-2 μm.

  18. 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

  19. Archimedes Revisited: A Faster, Better, Cheaper Method of Accurately Measuring the Volume of Small Objects

    Science.gov (United States)

    Hughes, Stephen W.

    2005-01-01

    A little-known method of measuring the volume of small objects based on Archimedes' principle is described, which involves suspending an object in a water-filled container placed on electronic scales. The suspension technique is a variation on the hydrostatic weighing technique used for measuring volume. The suspension method was compared with two…

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. ABSOLUTE POLARIMETRY AT RHIC.

    Energy Technology Data Exchange (ETDEWEB)

    OKADA; BRAVAR, A.; BUNCE, G.; GILL, R.; HUANG, H.; MAKDISI, Y.; NASS, A.; WOOD, J.; ZELENSKI, Z.; ET AL.

    2007-09-10

    Precise and absolute beam polarization measurements are critical for the RHIC spin physics program. Because all experimental spin-dependent results are normalized by beam polarization, the normalization uncertainty contributes directly to final physics uncertainties. We aimed to perform the beam polarization measurement to an accuracy Of {Delta}P{sub beam}/P{sub beam} < 5%. The absolute polarimeter consists of Polarized Atomic Hydrogen Gas Jet Target and left-right pairs of silicon strip detectors and was installed in the RHIC-ring in 2004. This system features proton-proton elastic scattering in the Coulomb nuclear interference (CNI) region. Precise measurements of the analyzing power A{sub N} of this process has allowed us to achieve {Delta}P{sub beam}/P{sub beam} = 4.2% in 2005 for the first long spin-physics run. In this report, we describe the entire set up and performance of the system. The procedure of beam polarization measurement and analysis results from 2004-2005 are described. Physics topics of AN in the CNI region (four-momentum transfer squared 0.001 < -t < 0.032 (GeV/c){sup 2}) are also discussed. We point out the current issues and expected optimum accuracy in 2006 and the future.

  2. 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.

  3. Novel methodology for accurate resolution of fluid signatures from multi-dimensional NMR well-logging measurements

    Science.gov (United States)

    Anand, Vivek

    2017-03-01

    A novel methodology for accurate fluid characterization from multi-dimensional nuclear magnetic resonance (NMR) well-logging measurements is introduced. This methodology overcomes a fundamental challenge of poor resolution of features in multi-dimensional NMR distributions due to low signal-to-noise ratio (SNR) of well-logging measurements. Based on an unsupervised machine-learning concept of blind source separation, the methodology resolves fluid responses from simultaneous analysis of large quantities of well-logging data. The multi-dimensional NMR distributions from a well log are arranged in a database matrix that is expressed as the product of two non-negative matrices. The first matrix contains the unique fluid signatures, and the second matrix contains the relative contributions of the signatures for each measurement sample. No a priori information or subjective assumptions about the underlying features in the data are required. Furthermore, the dimensionality of the data is reduced by several orders of magnitude, which greatly simplifies the visualization and interpretation of the fluid signatures. Compared to traditional methods of NMR fluid characterization which only use the information content of a single measurement, the new methodology uses the orders-of-magnitude higher information content of the entire well log. Simulations show that the methodology can resolve accurate fluid responses in challenging SNR conditions. The application of the methodology to well-logging data from a heavy oil reservoir shows that individual fluid signatures of heavy oil, water associated with clays and water in interstitial pores can be accurately obtained.

  4. Absolute measurement of {beta}{sub eff} and l on weapon-grade MOX fuel at the VENUS critical facility by means of the RAPJA technique

    Energy Technology Data Exchange (ETDEWEB)

    Baeten, P. E-mail: pbaeten@sckcen.be; Paepen, J.; Meer, K. van der; Abderrahim, H.A

    2001-03-01

    Measurements were performed at the VENUS critical facility for the validation of neutron codes in the case of a reactor core loaded with weapon-grade plutonium. Since the effective delayed neutron fraction {beta}{sub eff} and the mean neutron lifetime l are two important parameters in the characterisation of the dynamic behaviour of a reactor, an absolute measurement of these parameters is necessary to assure the correct validation of neutron transport codes. To meet this requirement, the RAPJA-technique was used. The RAPJA technique combines a Prompt Jump with a Rossi-Alpha measurement at the stationary subcritical level associated with the antireactivity level obtained after the Prompt Jump. The obtained results are well in accordance with calculated values for MOX-cores at VENUS. The measurements also show that uncertainties of 3 and 1.5% on respectively {beta}{sub eff} and l are achievable on a core loaded with weapon-grade plutonium.

  5. 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 h....... 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. 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.

  7. An ensemble average method to estimate absolute TEC using radio beacon-based differential phase measurements: Applicability to regions of large latitudinal gradients in plasma density

    Science.gov (United States)

    Thampi, Smitha V.; Bagiya, Mala S.; Chakrabarty, D.; Acharya, Y. B.; Yamamoto, M.

    2014-12-01

    A GNU Radio Beacon Receiver (GRBR) system for total electron content (TEC) measurements using 150 and 400 MHz transmissions from Low-Earth Orbiting Satellites (LEOS) is fabricated in house and made operational at Ahmedabad (23.04°N, 72.54°E geographic, dip latitude 17°N) since May 2013. This system receives the 150 and 400 MHz transmissions from high-inclination LEOS. The first few days of observations are presented in this work to bring out the efficacy of an ensemble average method to convert the relative TECs to absolute TECs. This method is a modified version of the differential Doppler-based method proposed by de Mendonca (1962) and suitable even for ionospheric regions with large spatial gradients. Comparison of TECs derived from a collocated GPS receiver shows that the absolute TECs estimated by this method are reliable estimates over regions with large spatial gradient. This method is useful even when only one receiving station is available. The differences between these observations are discussed to bring out the importance of the spatial differences between the ionospheric pierce points of these satellites. A few examples of the latitudinal variation of TEC during different local times using GRBR measurements are also presented, which demonstrates the potential of radio beacon measurements in capturing the large-scale plasma transport processes in the low-latitude ionosphere.

  8. Extrapolation of urn models via poissonization: accurate measurements of the microbial unknown.

    Directory of Open Access Journals (Sweden)

    Manuel E Lladser

    Full Text Available The availability of high-throughput parallel methods for sequencing microbial communities is increasing our knowledge of the microbial world at an unprecedented rate. Though most attention has focused on determining lower-bounds on the α-diversity i.e. the total number of different species present in the environment, tight bounds on this quantity may be highly uncertain because a small fraction of the environment could be composed of a vast number of different species. To better assess what remains unknown, we propose instead to predict the fraction of the environment that belongs to unsampled classes. Modeling samples as draws with replacement of colored balls from an urn with an unknown composition, and under the sole assumption that there are still undiscovered species, we show that conditionally unbiased predictors and exact prediction intervals (of constant length in logarithmic scale are possible for the fraction of the environment that belongs to unsampled classes. Our predictions are based on a poissonization argument, which we have implemented in what we call the Embedding algorithm. In fixed i.e. non-randomized sample sizes, the algorithm leads to very accurate predictions on a sub-sample of the original sample. We quantify the effect of fixed sample sizes on our prediction intervals and test our methods and others found in the literature against simulated environments, which we devise taking into account datasets from a human-gut and -hand microbiota. Our methodology applies to any dataset that can be conceptualized as a sample with replacement from an urn. In particular, it could be applied, for example, to quantify the proportion of all the unseen solutions to a binding site problem in a random RNA pool, or to reassess the surveillance of a certain terrorist group, predicting the conditional probability that it deploys a new tactic in a next attack.

  9. Three dimensional accurate morphology measurements of polystyrene standard particles on silicon substrate by electron tomography.

    Science.gov (United States)

    Hayashida, Misa; Kumagai, Kazuhiro; Malac, Marek

    2015-12-01

    Polystyrene latex (PSL) nanoparticle (NP) sample is one of the most widely used standard materials. It is used for calibration of particle counters and particle size measurement tools. It has been reported that the measured NP sizes by various methods, such as Differential Mobility Analysis, dynamic light scattering (DLS), optical microscopy (OM), scanning electron microscopy (SEM) and atomic force microscopy (AFM), differ from each other. Deformation of PSL NPs on mica substrate has been reported in AFM measurements: the lateral width of PSL NPs is smaller than their vertical height. To provide a reliable calibration standard, the deformation must be measured by a method that can reliably visualize the entire three dimensional (3D) shape of the PSL NPs. Here we present a method for detailed measurement of PSL NP 3D shape by means of electron tomography in a transmission electron microscope. The observed shape of the PSL NPs with 100 nm and 50 nm diameter were not spherical, but squished in direction perpendicular to the support substrate by about 7.4% and 12.1%, respectively. The high difference in surface energy of the PSL NPs and that of substrate together with their low Young modulus appear to explain the squishing of the NPs without presence of water film. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  10. Accurate Measurement of First Metatarsophalangeal Range of Motion in Patients With Hallux Rigidus.

    Science.gov (United States)

    Vulcano, Ettore; Tracey, Joseph A; Myerson, Mark S

    2016-05-01

    The reliability of range of motion (ROM) measurements has not been established for the hallux metatarsophalangeal (MTP) joint in patients with hallux rigidus. The aim of the present study was to prospectively assess the clinical versus radiographic difference in ROM of the arthritic hallux MTP joint. One hundred consecutive patients who presented with any grade of hallux rigidus were included in this prospective study to determine the hallux MTP range of motion. Clinical range of motion using a goniometer and radiographic range of motion on dynamic x-rays was recorded. The mean difference between clinical and radiographic dorsiflexion was 13 degrees (P dorsiflexion was equal to or less than radiographically measured dorsiflexion. The difference was significantly greater in patients with a clinical dorsiflexion of less than 30 degrees than in patients with 30 degrees or more. Radiographic measurement of hallux dorsiflexion had an excellent intra- and interobserver reliability. We describe a reliable, reproducible, and straightforward method of measuring hallux MTP ROM that improved upon measuring clinical ROM. Level II, prospective comparative study. © The Author(s) 2015.

  11. 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.

  12. Accurate measurement of nanoparticle charge, number and size with the ELPI+™ instrument

    Science.gov (United States)

    Lamminen, Erkki

    2011-07-01

    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+™ instrument is a completely new aerosol measurement instrument based on the widely used Electrical Low Pressure Impactor (ELPI) technique. ELPI+™ measures particle concentration and size in a wide size range from 6nm to 10μm 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+™ 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.

  13. 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...... and radiation pattern can be developed from simple considerations of the receiving, transmitting, and scattering properties of antennas. The main advantages of the technique are that no gain standard is required and a disturbing feedline to the antenna can be avoided. In addition to this the technique seems...

  14. 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.

  15. Achieving Climate Change Absolute Accuracy in Orbit

    Science.gov (United States)

    Wielicki, Bruce A.; Young, D. F.; Mlynczak, M. G.; Thome, K. J; Leroy, S.; Corliss, J.; Anderson, J. G.; Ao, C. O.; Bantges, R.; Best, F.; hide

    2013-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission will provide a calibration laboratory in orbit for the purpose of accurately measuring and attributing climate change. CLARREO measurements establish new climate change benchmarks with high absolute radiometric accuracy and high statistical confidence across a wide range of essential climate variables. CLARREO's inherently high absolute accuracy will be verified and traceable on orbit to Système Internationale (SI) units. The benchmarks established by CLARREO will be critical for assessing changes in the Earth system and climate model predictive capabilities for decades into the future as society works to meet the challenge of optimizing strategies for mitigating and adapting to climate change. The CLARREO benchmarks are derived from measurements of the Earth's thermal infrared spectrum (5-50 micron), the spectrum of solar radiation reflected by the Earth and its atmosphere (320-2300 nm), and radio occultation refractivity from which accurate temperature profiles are derived. The mission has the ability to provide new spectral fingerprints of climate change, as well as to provide the first orbiting radiometer with accuracy sufficient to serve as the reference transfer standard for other space sensors, in essence serving as a "NIST [National Institute of Standards and Technology] in orbit." CLARREO will greatly improve the accuracy and relevance of a wide range of space-borne instruments for decadal climate change. Finally, CLARREO has developed new metrics and methods for determining the accuracy requirements of climate observations for a wide range of climate variables and uncertainty sources. These methods should be useful for improving our understanding of observing requirements for most climate change observations.

  16. 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...

  17. An accurate method for power loss measurements in energy optimized apparatus and systems

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, P.; Blaabjerg, F.; Madsen, K.D.; Pedersen, J.K.; Ritchie, E.

    2001-07-01

    A calorimetric wattmeter has been built at Aalborg University, Institute of Energy Technology. The wattmeter is designed to measure power losses in power electronic components and applications at fixed temperatures. High accuracy has been achieved by using active constraints and optimizing flow and temperature conditions in the cooling circuit. (au)

  18. New insights for accurate chemically specific measurements of slow diffusing molecules

    Science.gov (United States)

    Hou, Jianbo; Madsen, Louis A.

    2013-02-01

    Investigating the myriad features of molecular transport in materials yields fundamental information for understanding processes such as ion conduction, chemical reactions, and phase transitions. Molecular transport especially impacts the performance of ion-containing liquids and polymeric materials when used as electrolytes and separation media, with applications encompassing battery electrolytes, reverse-osmosis membranes, mechanical transducers, and fuel cells. Nuclear magnetic resonance (NMR) provides a unique probe of molecular translations by allowing measurement of all mobile species via spectral selectivity, access to a broad range of transport coefficients, probing of any material direction, and investigation of variable lengthscales in a material, thus, tying morphology to transport. Here, we present new concepts to test for and guarantee robust diffusion measurements. We first employ a standard pulsed-field-gradient (PFG) calibration protocol using 2H2O and obtain expected results, but we observe crippling artifacts when measuring 1H-glycerol diffusion with the same experimental parameters. A mathematical analysis of 2H2O and glycerol signals in the presence of PFG transients show tight agreement with experimental observations. These analyses lead to our principal findings that (1) negligible artifacts observed with low gyromagnetic ratio (γ) nuclei may become dominant when observing high γ nuclei, and (2) reducing the sample dimension along the gradient direction predictably reduces non-ideal behaviors of NMR signals. We further provide a useful quantitative strategy for error minimization when measuring diffusing species slower than the one used for gradient calibration.

  19. Do plant traits retrieved from a database accurately predict on-site measurements?

    NARCIS (Netherlands)

    Cordlandwehr, V.; Meredith, R.L.; Ozinga, W.A.; Bekker, R.M.; Groenendael, van J.M.; Bakker, J.P.

    2013-01-01

    1. Trait-based approaches are increasingly used to obtain an insight into the functional aspects of plant communities. Since measuring traits can be time-consuming, large international databases of plant traits are being compiled to share the effort. From these databases, average trait values are

  20. Do plant traits retrieved from a database accurately predict on-site measurements?

    NARCIS (Netherlands)

    Cordlandwehr, Verena; Meredith, Rebecca L.; Ozinga, Wim A.; Bekker, Renée M.; van Groenendael, Jan M.; Bakker, Jan P.

    Trait-based approaches are increasingly used to obtain an insight into the functional aspects of plant communities. Since measuring traits can be time-consuming, large international databases of plant traits are being compiled to share the effort. From these databases, average trait values are often

  1. Optical coherence tomography enables accurate measurement of equine cartilage thickness for determination of speed of sound

    NARCIS (Netherlands)

    Puhakka, Pia H.; te Moller, Nikae; Tanska, Petri; Saarakkala, Simo; Tiitu, Virpi; Korhonen, Rami K.; Brommer, Harold; Virén, Tuomas; Jurvelin, Jukka S.; Töyräs, Juha

    2016-01-01

    Background and purpose — Arthroscopic estimation of articular cartilage thickness is important for scoring of lesion severity, and measurement of cartilage speed of sound (SOS)—a sensitive index of changes in cartilage composition. We investigated the accuracy of optical coherence tomography (OCT)

  2. 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.

  3. Are sap flow measurements useful for determining water use of fruit orchards, when absolute values are important?

    CSIR Research Space (South Africa)

    Taylor, NJ

    2013-06-01

    Full Text Available in a macadamia orchard. The use of a visually measured wounding width yielded water use figures much lower than expected and as a result a wound effect calibration coefficient was determined by calibrating the sap flow measurements against...

  4. Using relative and absolute measures for monitoring health inequalities: Experiences from cross-national analyses on maternal and child health

    NARCIS (Netherlands)

    A.J. Houweling (Tanja); A.E. Kunst (Anton); M. Huisman (Martijn); J.P. Mackenbach (Johan)

    2007-01-01

    textabstractBackground. As reducing socio-economic inequalities in health is an important public health objective, monitoring of these inequalities is an important public health task. The specific inequality measure used can influence the conclusions drawn, and there is no consensus on which measure

  5. Two-photon LIF on the HIT-SI3 experiment: Absolute density and temperature measurements of deuterium neutrals

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Drew, E-mail: dbelliott@mix.wvu.edu; Siddiqui, Umair; Scime, Earl [Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26056 (United States); Sutherland, Derek; Everson, Chris; Morgan, Kyle; Hossack, Aaron; Nelson, Brian; Jarboe, Tom [Department of Aerospace Engineering, University of Washington, Seattle, Washington 98105 (United States)

    2016-11-15

    Two-photon laser-induced fluorescence measurements were performed on the helicity injected torus (HIT-SI3) device to determine the density and temperature of the background neutral deuterium population. Measurements were taken in 2 ms long pulsed plasmas after the inductive helicity injectors were turned off. Attempts to measure neutrals during the main phase of the plasma were unsuccessful, likely due to the density of neutrals being below the detection threshold of the diagnostic. An unexpectedly low density of atomic deuterium was measured in the afterglow; roughly 100 times lower than the theoretical prediction of 10{sup 17} m{sup −3}. The neutral temperatures measured were on the order of 1 eV. Temporally and spatially resolved neutral density and temperature data are presented.

  6. A Procedure for Accurately Measuring the Shaker Overturning Moment During Random Vibration Tests

    Science.gov (United States)

    Nayeri, Reza D.

    2011-01-01

    Motivation: For large system level random vibration tests, there may be some concerns about the shaker's capability for the overturning moment. It is the test conductor's responsibility to predict and monitor the overturning moment during random vibration tests. If the predicted moment is close to the shaker's capability, test conductor must measure the instantaneous moment at low levels and extrapolate to higher levels. That data will be used to decide whether it is safe to proceed to the next test level. Challenge: Kistler analog formulation for computing the real-time moment is only applicable to very limited cases in which we have 3 or 4 load cells installed at shaker interface with hardware. Approach: To overcome that limitation, a simple procedure was developed for computing the overturning moment time histories using the measured time histories of the individual load cells.

  7. 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.

  8. Measuring Accurately Single-Phase Sinusoidal and Non-Sinusoidal Power.

    Science.gov (United States)

    1983-01-01

    made by the voltage and current circuits. The two methods for connecting the Model 255 wattmeter for measuring power arc shown in figure 6.1(a) and 6.1(b...insertion losses due to the physical connections made by the voltage and current- coil circuits. The two method :, for connecting the P-3 wattmeter for...P-3 Electrodynamometer wattmeters , two Clarke-Hess Model 255 Digital Wattmeters and one General Electric Type VM- 63-S Induction Watthour Meter. The

  9. 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

  10. Repeated Measurement of Absolute and Relative Judgments of Loudness: Clinical Relevance for Prescriptive Fitting of Aided Target Gains for soft, Comfortable, and Loud, But Ok Sound Levels.

    Science.gov (United States)

    Formby, Craig; Payne, JoAnne; Yang, Xin; Wu, Delphanie; Parton, Jason M

    2017-02-01

    This study was undertaken with the purpose of streamlining clinical measures of loudness growth to facilitate and enhance prescriptive fitting of nonlinear hearing aids. Repeated measures of loudness at 500 and 3,000 Hz were obtained bilaterally at monthly intervals over a 6-month period from three groups of young adult listeners. All volunteers had normal audiometric hearing sensitivity and middle ear function, and all denied problems related to sound tolerance. Group 1 performed judgments of soft and loud, but OK for presentation of ascending sound levels. We defined these judgments operationally as absolute judgments of loudness. Group 2 initially performed loudness judgments across a continuum of seven loudness categories ranging from judgments of very soft to uncomfortably loud for presentation of ascending sound levels per the Contour Test of Loudness; we defined these judgments as relative judgments of loudness. In the same session, they then performed the absolute judgments for soft and loud, but OK sound levels. Group 3 performed the same set of loudness judgments as did group 2, but the task order was reversed such that they performed the absolute judgments initially within each test session followed by the relative judgments. The key findings from this study were as follows: (1) Within group, the absolute and relative tasks yielded clinically similar judgments for soft and for loud, but OK sound levels. These judgments were largely independent of task order, ear, frequency, or trial order within a given session. (2) Loudness judgments increased, on average, by ∼3 dB between the first and last test session, which is consistent with the commonly reported acclimatization effect reported for incremental changes in loudness discomfort levels as a consequence of chronic bilateral hearing aid use. (3) Measured and predicted comfortable judgments of loudness were in good agreement for the individual listener and for groups of listeners. These comfortable

  11. An X-band waveguide measurement technique for the accurate characterization of materials with low dielectric loss permittivity.

    Science.gov (United States)

    Allen, Kenneth W; Scott, Mark M; Reid, David R; Bean, Jeffrey A; Ellis, Jeremy D; Morris, Andrew P; Marsh, Jeramy M

    2016-05-01

    In this work, we present a new X-band waveguide (WR90) measurement method that permits the broadband characterization of the complex permittivity for low dielectric loss tangent material specimens with improved accuracy. An electrically long polypropylene specimen that partially fills the cross-section is inserted into the waveguide and the transmitted scattering parameter (S21) is measured. The extraction method relies on computational electromagnetic simulations, coupled with a genetic algorithm, to match the experimental S21 measurement. The sensitivity of the technique to sample length was explored by simulating specimen lengths from 2.54 to 15.24 cm, in 2.54 cm increments. Analysis of our simulated data predicts the technique will have the sensitivity to measure loss tangent values on the order of 10(-3) for materials such as polymers with relatively low real permittivity values. The ability to accurately characterize low-loss dielectric material specimens of polypropylene is demonstrated experimentally. The method was validated by excellent agreement with a free-space focused-beam system measurement of a polypropylene sheet. This technique provides the material measurement community with the ability to accurately extract material properties of low-loss material specimen over the entire X-band range. This technique could easily be extended to other frequency bands.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Absolute measurement of anti. nu. /sub p/ for /sup 252/Cf using the ORNL large liquid scintillator neutron detector

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, R.R.; Gwin, R.; Ingle, R.

    1981-08-01

    The ORNL large liquid scintillator detector was used in a precise determination of anti ..nu../sub p/, the number of neutrons emitted promptly, for spontaneous fission of /sup 252/Cf. Measurements of the detector efficiency over a broad energy region were made by means of a proton-recoil technique employing the ORELA white neutron source. Monte Carlo calculation of the detector efficiency for a spectrum representative of /sup 252/Cf fission neutrons was calibrated with these elaborate measurements. The unusually flat response of the neutron detector resulted in elimination of several known sources of error. Experimental measurement was coupled with calculational methods to correct for other known errors. These measurements lead to an unusually small estimated uncertainty of 0.2% in the value obtained, anti ..nu../sub p/ = 3.773 +- 0.007.

  17. Measurements of periods, relative abundances and absolute yields of delayed neutrons from fast neutron induced fission of {sup 237}Np

    Energy Technology Data Exchange (ETDEWEB)

    Piksaikine, V. [Institute of Physics and Power Engineering, Obninsk (Russian Federation)

    1997-03-01

    The experimental method for measurements of the delayed neutron yields and period is presented. The preliminary results of the total yield, relative abundances and periods are shown comparing with the previously reported values. (J.P.N.)

  18. 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.

  19. Examining factors that may influence accurate measurement of testosterone in sea turtles.

    Science.gov (United States)

    Graham, Katherine M; Mylniczenko, Natalie D; Burns, Charlene M; Bettinger, Tammie L; Wheaton, Catharine J

    2016-01-01

    Differences in reported testosterone concentrations in male sea turtle blood samples are common in the veterinary literature, but may be accounted for by differences in sample handling and processing prior to assay. Therefore, our study was performed to determine best practices for testosterone analysis in male sea turtles (Caretta caretta and Chelonia mydas). Blood samples were collected into 5 collection tube types, and assay validation and measured testosterone concentrations were compared across different sample storage (fresh, refrigerated 1 week, or frozen), extraction (unextracted or ether-extracted), and processing treatment (untreated, homogenized, or dissociation reagent) conditions. Ether-extracted and dissociation reagent-treated samples validated in all conditions tested and are recommended for use, as unextracted samples validated only if assayed fresh. Dissociation reagent treatment was simpler to perform than ether extraction and resulted in total testosterone concentrations ~2.7-3.5 times greater than free testosterone measured in ether-extracted samples. Sample homogenization did not affect measured testosterone concentrations, and could be used to increase volume in gelled samples. An annual seasonal testosterone increase was observed in both species when ether extraction or dissociation reagent treatment was used. Annual deslorelin implant treatments in a Chelonia mydas male resulted in suppression of seasonal testosterone following the fourth treatment. Seasonal testosterone patterns resumed following discontinuation of deslorelin. Comparison of in-house and commercially available enzyme immunoassay kits revealed similar patterns of seasonal testosterone increases and deslorelin-induced suppression. Our study highlights the importance of methodological validation and provides laboratorians with best practices for testosterone enzyme immunoassay in sea turtles. © 2015 The Author(s).

  20. Fast and Accurate Face Orientation Measurement in Low-resolution Images on Embedded Hardware

    OpenAIRE

    Hulens, Dries; Van Beeck, Kristof; Goedemé, Toon

    2016-01-01

    In numerous applications it is important to collect information about the gaze orientation or head-angle of a person. Examples are measuring the alertness of a car driver to see if he is still awake, or the attentiveness of people crossing a street to see if they noticed the cars driving by. In our own application we want to apply cinematographic rules (e.g. the rule of thirds where a face should be positioned left or right in the frame depending on the gaze direction) on images taken from an...

  1. Possibility of detecting anisotropic expansion of the universe by very accurate astrometry measurements.

    Science.gov (United States)

    Quercellini, Claudia; Quartin, Miguel; Amendola, Luca

    2009-04-17

    Refined astrometry measurements allow us to detect large-scale deviations from isotropy through real-time observations of changes in the angular separation between sources at cosmic distances. This "cosmic parallax" effect is a powerful consistency test of the Friedmann-Robertson-Walker metric and may set independent constraints on cosmic anisotropy. We apply this novel general test to Lemaitre-Tolman-Bondi cosmologies with off-center observers and show that future satellite missions such as Gaia might achieve accuracies that would put limits on the off-center distance which are competitive with cosmic microwave background dipole constraints.

  2. Progress on accurate measurement of the Planck constant: watt balance and counting atoms

    OpenAIRE

    Li, Shisong; Zhang, Zhonghua; Zhao, Wei; Li, Zhengkun; Huang, Songling

    2014-01-01

    The Planck constant $h$ is one of the most significant constants in quantum physics. Recently, the precision measurement of the numeral value of $h$ has been a hot issue due to its important role in establishment for both a new SI and a revised fundamental physical constant system. Up to date, two approaches, the watt balance and counting atoms, have been employed to determine the Planck constant at a level of several parts in $10^8$. In this paper, the principle and progress on precision mea...

  3. Accurate low-rank matrix recovery from a small number of linear measurements

    CERN Document Server

    Candes, Emmanuel J

    2009-01-01

    We consider the problem of recovering a lowrank matrix M from a small number of random linear measurements. A popular and useful example of this problem is matrix completion, in which the measurements reveal the values of a subset of the entries, and we wish to fill in the missing entries (this is the famous Netflix problem). When M is believed to have low rank, one would ideally try to recover M by finding the minimum-rank matrix that is consistent with the data; this is, however, problematic since this is a nonconvex problem that is, generally, intractable. Nuclear-norm minimization has been proposed as a tractable approach, and past papers have delved into the theoretical properties of nuclear-norm minimization algorithms, establishing conditions under which minimizing the nuclear norm yields the minimum rank solution. We review this spring of emerging literature and extend and refine previous theoretical results. Our focus is on providing error bounds when M is well approximated by a low-rank matrix, and ...

  4. 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...

  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. Compensation of the exhaust gas transport dynamics for accurate instantaneous emission measurements.

    Science.gov (United States)

    Ajtay, Delia; Weilenmann, Martin

    2004-10-01

    Instantaneous emission models of vehicles describe the amount of emitted pollutants as a function of the driving state of the car. Emission measurements of chassis dynamometer tests with high time resolution are necessary for the development of such models. However, the dynamics of gas transport in both the exhaust system of the car and the measurement line last significantly longer than 1 s. In a simplified approach, the transport dynamics can be divided into two parts: a perfect time delay, corresponding to a piston-like transport of the exhaust gas, and a dynamic part, corresponding to the mixing of gases by turbulence along the way. This determines the occurrence of emission peaks that are longer in time and lower in height at the analyzer than they actually are in the vehicle at their location of formation. It is shown here how the sharp emission signals at their location of formation can be reconstructed from the flattened emission signals recorded at the analyzer by using signal theory approaches. A comparison between the reconstructions quality when using the raw or the dilution analyzer system is also given.

  7. 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.

  8. 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.

  9. Accurate measurement of JHHin overlapped signals by a TOCSY-edited SERF Experiment.

    Science.gov (United States)

    Fredi, André; Nolis, Pau; Parella, Teodor

    2017-06-01

    Selective refocusing (GSERF or the recent PSYCHEDELIC) experiments were originally designed to determine all proton-proton coupling constants (J HH ) for a selected proton resonance. They work for isolated signals on which selective excitation can be successfully applied but, as it happens in other selective experiments, fail for overlapped signals. To circumvent this limitation, a doubly-selective TOCSY-GSERF scheme is presented for the measurement of J HH in protons resonating in crowded regions. This new experiment takes advantage of the editing features of an initial TOCSY transfer to uncover hidden resonances that become accessible to perform the subsequent frequency-selective refocusing. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  10. 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

    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...... of dose rate (1–1014 rad s−1). Upon irradiation of the film, the profile of the radiation field is registered as a permanent colored image of the dose distribution. Unlike most other types of dyed plastic dose meters, the optical density produced by irradiation is in most cases stable for periods...

  11. How Accurately Can We Measure Galaxy Environment at High Redshift Using Only Photometric Redshifts?

    Science.gov (United States)

    Florez, Jonathan; Jogee, Shardha; Sherman, Sydney; Papovich, Casey J.; Finkelstein, Steven L.; Stevans, Matthew L.; Kawinwanichakij, Lalitwadee; Ciardullo, Robin; Gronwall, Caryl; SHELA/HETDEX

    2017-06-01

    We use a powerful synergy of six deep photometric surveys (Herschel SPIRE, Spitzer IRAC, NEWFIRM K-band, DECam ugriz, and XMM X-ray) and a future optical spectroscopic survey (HETDEX) in the Stripe 82 field to study galaxy evolution during the 1.9 environment using only our photometric redshifts. We compare both local and large-scale measures of environment (e.g., projected two-point correlation function, projected nearest neighbor densities, and galaxy counts within some projected aperture) at different photometric redshifts to cosmological simulations in order to quantify the uncertainty in our estimates of environment. We also explore how robustly one can recover the variation of galaxy properties with environment, when using only photometric redshifts. In the era of large photometric surveys, this work has broad implications for studies addressing the impact of environment on galaxy evolution at early cosmic epochs. We acknowledge support from NSF grants AST-1614798, AST-1413652 and NSF GRFP grant DGE-1610403.

  12. 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.

  13. Defense Automated Neurobehavioral Assessment Accurately Measures Cognition in Patients Undergoing Electroconvulsive Therapy for Major Depressive Disorder.

    Science.gov (United States)

    Hollinger, Kristen R; Woods, Steven R; Adams-Clark, Alexis; Choi, So Yung; Franke, Caroline L; Susukida, Ryoko; Thompson, Carol; Reti, Irving M; Kaplin, Adam I

    2017-10-03

    The Defense Automated Neurobehavioral Assessment (DANA) is an electronic cognitive test battery. The present study compares DANA to the standard Mini-Mental State Examination (MMSE) in subjects undergoing electroconvulsive therapy for the treatment of major depressive disorder. Seventeen inpatient subjects in the Johns Hopkins Hospital Department of Psychiatry were administered longitudinal paired DANA and MMSE tests (7.6 ± 4.1 per patient) from January 10, 2014 to September 26, 2014. Regression analyses were conducted (with or without MMSE scores of 30) to study the impact of the MMSE upper limit, and within-subject regression analyses were conducted to compare MMSE and DANA scores over time. Statistically significant relationships were measured between DANA and MMSE scores. Relationships strengthened when MMSE scores of 30 were omitted from analyses, demonstrating a ceiling effect of the MMSE. Within-subject analyses revealed relationships between MMSE and DANA scores over the duration of the inpatient stay. Defense Automated Neurobehavioral Assessment is an electronic, mobile, repeatable, sensitive, and valid method of measuring cognition over time in depressed patients undergoing electroconvulsive therapy treatment. Automation of the DANA allows for more frequent cognitive testing in a busy clinical setting and enhances cognitive assessment sensitivity with a timed component to each test.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

  14. Accurately measuring the quality and effectiveness of lumbar surgery in registry efforts: determining the most valid and responsive instruments.

    Science.gov (United States)

    Godil, Saniya S; Parker, Scott L; Zuckerman, Scott L; Mendenhall, Stephen K; Glassman, Steven D; McGirt, Matthew J

    2014-12-01

    Prospective registries have emerged as a feasible way to capture real-world care across large patient populations. However, the proven validity of more robust and cumbersome patient-reported outcomes instruments (PROis) must be balanced with what is feasible to apply in large-scale registry efforts. To determine the relative validity and responsiveness of common PROis in accurately determining effectiveness of lumbar fusion for degenerative lumbar spondylolisthesis in registry efforts. Prospective cohort study. Fifty-eight patients undergoing transforaminal lumbar interbody fusion (TLIF) for degenerative lumbar spondylolisthesis Patient-reported outcome measures for pain (numeric rating scale for back and leg pain [NRS-BP, NRS-LP]), disability (Oswestry Disability Index [ODI]), general health (Short Form [SF]-12), quality of life (QOL) (EuroQol five dimensions [EQ-5D]), and depression (Zung depression scale [ZDS]) were assessed. Fifty-eight patients undergoing primary TLIF for lumbar spondylolisthesis were entered into an institutional registry and prospectively followed for 2 years. Baseline and 2-year patient-reported outcomes were assessed. To assess the validity of PROis to discriminate between effective and noneffective improvements, receiver operating characteristic curves were generated for each outcomes instrument. An area under the curve (AUC) of ≥0.80 was considered an accurate discriminator. The difference between standardized response means (SRMs) in patients reporting meaningful improvement versus not was calculated to determine the relative responsiveness of each instrument. For pain and disability, ODI had AUC=0.94, suggesting it as an accurate discriminator of meaningful improvement. Oswestry Disability Index was most responsive to postoperative improvement (SRM difference: 2.18), followed by NRS-BP and NRS-LP. For general health and QOL, SF-12 physical component score (AUC: 0.90), ZDS (AUC: 0.89), and SF-12 mental component score (AUC: 0.85) were

  15. Measurement procedure for absolute broadband infrared up-conversion photoluminescent quantum yields: correcting for absorption/re-emission.

    Science.gov (United States)

    MacDougall, Sean K W; Ivaturi, Aruna; Marques-Hueso, Jose; Richards, Bryce S

    2014-06-01

    The internal photoluminescent quantum yield (iPLQY)--defined as the ratio of emitted photons to those absorbed--is an important parameter in the evaluation and application of luminescent materials. The iPLQY is rarely reported due to the complexities in the calibration of such a measurement. Herein, an experimental method is proposed to correct for re-emission, which leads to an underestimation of the absorption under broadband excitation. Although traditionally the iPLQY is measured using monochromatic sources for linear materials, this advancement is necessary for nonlinear materials with wavelength dependent iPLQY, such as the application of up-conversion to solar energy harvesting. The method requires an additional measurement of the emission line shape that overlaps with the excitation and absorption spectra. Through scaling of the emission spectrum, at the long wavelength edge where an overlap of excitation does not occur, it is possible to better estimate the value of iPLQY. The method has been evaluated for a range of nonlinear material concentrations and under various irradiances to analyze the necessity and boundary conditions that favor the proposed method. Use of this refined method is important for a reliable measurement of iPLQY under a broad illumination source such as the Sun.

  16. Absolute atomic oxygen and nitrogen densities in radio-frequency driven atmospheric pressure cold plasmas: Synchrotron vacuum ultra-violet high-resolution Fourier-transform absorption measurements

    Energy Technology Data Exchange (ETDEWEB)

    Niemi, K.; O' Connell, D.; Gans, T. [York Plasma Institute, Department of Physics, University of York, York YO10 5DD (United Kingdom); Oliveira, N. de; Joyeux, D.; Nahon, L. [Synchrotron Soleil, l' Orme des Merisiers, St. Aubin BP 48, 91192 Gif sur Yvette Cedex (France); Booth, J. P. [Laboratoire de Physique des Plasmas-CNRS, Ecole Polytechnique, 91128 Palaiseau (France)

    2013-07-15

    Reactive atomic species play a key role in emerging cold atmospheric pressure plasma applications, in particular, in plasma medicine. Absolute densities of atomic oxygen and atomic nitrogen were measured in a radio-frequency driven non-equilibrium plasma operated at atmospheric pressure using vacuum ultra-violet (VUV) absorption spectroscopy. The experiment was conducted on the DESIRS synchrotron beamline using a unique VUV Fourier-transform spectrometer. Measurements were carried out in plasmas operated in helium with air-like N{sub 2}/O{sub 2} (4:1) admixtures. A maximum in the O-atom concentration of (9.1 {+-} 0.7) Multiplication-Sign 10{sup 20} m{sup -3} was found at admixtures of 0.35 vol. %, while the N-atom concentration exhibits a maximum of (5.7 {+-} 0.4) Multiplication-Sign 10{sup 19} m{sup -3} at 0.1 vol. %.

  17. Measurement of the absolute branching ratio of the K{sup +}→π{sup +}π{sup −}π{sup +}(γ) decay with the KLOE detector

    Energy Technology Data Exchange (ETDEWEB)

    Babusci, D. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Balwierz-Pytko, I. [Institute of Physics, Jagiellonian University, Cracow (Poland); Bencivenni, G.; Bloise, C.; Bossi, F. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Branchini, P. [INFN Sezione di Roma Tre, Roma (Italy); Budano, A. [Dipartimento di Matematica e Fisica dell' Università “Roma Tre”, Roma (Italy); INFN Sezione di Roma Tre, Roma (Italy); Caldeira Balkeståhl, L. [Department of Physics and Astronomy, Uppsala University, Uppsala (Sweden); Ceradini, F. [Dipartimento di Matematica e Fisica dell' Università “Roma Tre”, Roma (Italy); INFN Sezione di Roma Tre, Roma (Italy); Ciambrone, P. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Curciarello, F. [Dipartimento di Fisica e Scienze della Terra dell' Università di Messina, Messina (Italy); INFN Sezione di Catania, Catania (Italy); Czerwiński, E. [Institute of Physics, Jagiellonian University, Cracow (Poland); Danè, E. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); De Leo, V. [Dipartimento di Fisica e Scienze della Terra dell' Università di Messina, Messina (Italy); INFN Sezione di Catania, Catania (Italy); De Lucia, E. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); De Robertis, G. [INFN Sezione di Bari, Bari (Italy); De Santis, A. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); De Simone, P., E-mail: patrizia.desimone@lnf.infn.it [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Di Cicco, A. [Dipartimento di Matematica e Fisica dell' Università “Roma Tre”, Roma (Italy); INFN Sezione di Roma Tre, Roma (Italy); and others

    2014-11-10

    The absolute branching ratio of the K{sup +}→π{sup +}π{sup −}π{sup +}(γ) decay, inclusive of final-state radiation, has been measured using ∼17 million tagged K{sup +} mesons collected with the KLOE detector at DAΦNE, the Frascati ϕ-factory. The result is: BR(K{sup +}→π{sup +}π{sup −}π{sup +}(γ))=0.05565±0.00031{sub stat}±0.00025{sub syst} a factor ≃ 5 more precise with respect to the previous result. This work completes the program of precision measurements of the dominant kaon branching ratios at KLOE.

  18. Accurate measurement of a fission chamber efficiency using the prompt fission neutron method

    Directory of Open Access Journals (Sweden)

    Mathieu Ludovic

    2017-01-01

    Full Text Available Fission Chambers (FC are often used to determine fission cross sections and to measure the neutron beam flux via standard neutron-induced fission reactions. Thus, the fission detection efficiency is a key parameter. Several methods exist to determine this efficiency, with a final accuracy not better than 1%. The detection of prompt fission neutrons allows events related to the fission process to be tagged, and enables the efficiency to be inferred with accuracy of the order of few 0.1%. This method is very robust since it is independent in first order to several factors like geometry, used materials or neutron contour selection. To obtain high accuracy, few corrections have still to be taken into account. In particular, the neutron detectors have to cover several detection angles. In addition, the background contribution of neutrons from cosmic rays or from an accelerator has to be removed. Several experiments based on the use of a 252Cf source are presented to describe all these points.

  19. Identifying clinical measures that most accurately reflect the progression of disability in Parkinson disease.

    Science.gov (United States)

    Ellis, Terry D; Cavanaugh, James T; Earhart, Gammon M; Ford, Matthew P; Foreman, K Bo; Thackeray, Anne; Thiese, Matthew S; Dibble, Leland E

    2016-04-01

    The temporal relationship between disease and disability progression in Parkinson disease (PD) is not well understood. Our objective was to describe the natural, multidimensional trajectory of disability in persons with PD over a two-year period. We conducted a multi-center, prospective cohort study involving four institutions. Data were collected at baseline and at 6-month intervals over 2 years using standardized clinical tests representing three World Health Organization defined disability domains: impairment, activity limitation, and participation restriction. Unadjusted mixed effects growth models characterized trajectories of disability in the three disability domains. The data set was analyzed using restricted maximum likelihood (REML) estimation. Standardized estimates of change were also computed using Cohen's d for each measure. Of the 266 enrolled participants, we analysed data from individuals who participated in at least 3 assessments (n = 207, 79%). Rates of disability progression over the 2-year period differed across domains. Moderate effects were detected for motor impairment (d = .28) and walking-related activity limitation (gait-related balance (d = .31); gait speed (d = .30)). Marginal effects were noted for upper extremity-related activity limitation (d = .11) and health-related quality of life participation restriction (d = .08). The natural trajectory of walking-related activity limitation was the most potent indicator of evolving disability, suggesting that routine assessment of walking and periodic rehabilitation is likely to be warranted for many persons with PD. Natural trajectories of disability provide important comparison data for future intervention studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Accurate Measurements of Free Flight Drag Coefficients with Amateur Doppler Radar

    CERN Document Server

    Courtney, Elya; Courtney, Michael

    2016-01-01

    In earlier papers, techniques have been described using optical chronographs to determine free flight drag coefficients with an accuracy of 1-2%, accomplished by measuring near and far velocities of projectiles in flight over a known distance. Until recently, Doppler radar has been prohibitively expensive for many users. This paper reports results of exploring potential applications and accuracy using a recently available, inexpensive (< $600 US) amateur Doppler radar system to determine drag coefficients for projectiles of various sizes (4.4 mm to 9 mm diameter) and speeds (M0.3 to M3.0). In many cases, drag coefficients can be determined with an accuracy of 1% or better if signal-to-noise ratio is sufficient and projectiles vary little between trials. It is also straightforward to design experiments for determining drag over a wide range of velocities. Experimental approaches and limitations are described. Overall, the amateur radar system shows greater accuracy, ease of use, and simplicity compared with...

  1. S3 HMBC hetero: Spin-State-Selective HMBC for accurate measurement of long-range heteronuclear coupling constants

    Science.gov (United States)

    Hoeck, Casper; Gotfredsen, Charlotte H.; Sørensen, Ole W.

    2017-02-01

    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 13C-1H methine pairs. This amounts to converting the spin-state selectivity from 1H spin states to 13C spin states in the spectra of long-range coupled 1H spins, allowing convenient measurement of heteronuclear coupling constants similar to other S3 or E.COSY-type methods. As usual in this type 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.

  2. The need for preoperative baseline arm measurement to accurately quantify breast cancer-related lymphedema.

    Science.gov (United States)

    Sun, Fangdi; Skolny, Melissa N; Swaroop, Meyha N; Rawal, Bhupendra; Catalano, Paul J; Brunelle, Cheryl L; Miller, Cynthia L; Taghian, Alphonse G

    2016-06-01

    Breast cancer-related lymphedema (BCRL) is a feared outcome of breast cancer treatment, yet the push for early screening is hampered by a lack of standardized quantification. We sought to determine the necessity of preoperative baseline in accounting for temporal changes of upper extremity volume. 1028 women with unilateral breast cancer were prospectively screened for lymphedema by perometry. Thresholds were defined: relative volume change (RVC) ≥10 % for clinically significant lymphedema and ≥5 % including subclinical lymphedema. The first postoperative measurement (pseudo-baseline) simulated the case of no baseline. McNemar's test and binomial logistic regression models were used to analyze BCRL misdiagnoses. Preoperatively, 28.3 and 2.9 % of patients had arm asymmetry of ≥5 and 10 %, respectively. Without baseline, 41.6 % of patients were underdiagnosed and 40.1 % overdiagnosed at RVC ≥ 5 %, increasing to 50.0 and 54.8 % at RVC ≥ 10 %. Increased pseudo-baseline asymmetry, increased weight change between baselines, hormonal therapy, dominant use of contralateral arm, and not receiving axillary lymph node dissection (ALND) were associated with increased risk of underdiagnosis at RVC ≥ 5 %; not receiving regional lymph node radiation was significant at RVC ≥ 10 %. Increased pseudo-baseline asymmetry, not receiving ALND, and dominant use of ipsilateral arm were associated with overdiagnosis at RVC ≥ 5 %; increased pseudo-baseline asymmetry and not receiving ALND were significant at RVC ≥ 10 %. The use of a postoperative proxy even early after treatment results in poor sensitivity for identifying BCRL. Providers with access to patients before surgery should consider the consequent need for proper baseline, with specific strategy tailored by institution.

  3. Novel methodology for accurate resolution of fluid signatures from multi-dimensional NMR well-logging measurements.

    Science.gov (United States)

    Anand, Vivek

    2017-03-01

    A novel methodology for accurate fluid characterization from multi-dimensional nuclear magnetic resonance (NMR) well-logging measurements is introduced. This methodology overcomes a fundamental challenge of poor resolution of features in multi-dimensional NMR distributions due to low signal-to-noise ratio (SNR) of well-logging measurements. Based on an unsupervised machine-learning concept of blind source separation, the methodology resolves fluid responses from simultaneous analysis of large quantities of well-logging data. The multi-dimensional NMR distributions from a well log are arranged in a database matrix that is expressed as the product of two non-negative matrices. The first matrix contains the unique fluid signatures, and the second matrix contains the relative contributions of the signatures for each measurement sample. No a priori information or subjective assumptions about the underlying features in the data are required. Furthermore, the dimensionality of the data is reduced by several orders of magnitude, which greatly simplifies the visualization and interpretation of the fluid signatures. Compared to traditional methods of NMR fluid characterization which only use the information content of a single measurement, the new methodology uses the orders-of-magnitude higher information content of the entire well log. Simulations show that the methodology can resolve accurate fluid responses in challenging SNR conditions. The application of the methodology to well-logging data from a heavy oil reservoir shows that individual fluid signatures of heavy oil, water associated with clays and water in interstitial pores can be accurately obtained. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Absolute measurement of {beta} emitters with a 4 {pi} counter; Mesure absolue des emetteurs {beta} au compteur 4 {pi}

    Energy Technology Data Exchange (ETDEWEB)

    Le Gallic, Y. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1959-06-15

    The object of this work is to investigate the conditions under which the activity of {beta}-emitting radionuclides may be measured with a maximum of precision, and as a result to study the relevant corrections. The various problems relating to activity measurements with a 4 {pi} counter have been examined successively: - comparison of 4 {pi}, GM and proportional counters; - study of the preparation of sources; - corrections on the counting of sources; - self-absorption; - correction for absorption. The precision obtained on these measurements varies from 1.2 to 3 per cent, with the result that the 4 {pi} counter can be considered a very satisfactory calibration instrument. (author) [French] Le but de ce travail est de rechercher les conditions permettant d'obtenir avec le maximum de precision, la mesure de l'activite des radionuclides se desintegrant par emission et par consequent d'etudier les corrections qui s'y rapportent. Nous avons examine successivement les differents problemes se rapportant aux mesures d'activite au compteur 4 {pi}: - Comparaison des compteurs 4 {pi}, GM et proportionnel; - etude de la preparation des sources; - corrections sur la numeration des sources; - auto-absorption; - correction d'absorption. La precision obtenue dans ces mesures, variant de 1,2 a 3 pour cent, on peut donc considerer le compteur 4 {pi} comme un instrument d'etalonnage tres satisfaisant. (auteur)

  5. Utility of relative and absolute measures of mammographic density vs clinical risk factors in evaluating breast cancer risk at time of screening mammography.

    Science.gov (United States)

    Abdolell, Mohamed; Tsuruda, Kaitlyn M; Lightfoot, Christopher B; Payne, Jennifer I; Caines, Judy S; Iles, Sian E

    2016-01-01

    Various clinical risk factors, including high breast density, have been shown to be associated with breast cancer. The utility of using relative and absolute area-based breast density-related measures was evaluated as an alternative to clinical risk factors in cancer risk assessment at the time of screening mammography. Contralateral mediolateral oblique digital mammography images from 392 females with unilateral breast cancer and 817 age-matched controls were analysed. Information on clinical risk factors was obtained from the provincial breast-imaging information system. Breast density-related measures were assessed using a fully automated breast density measurement software. Multivariable logistic regression was conducted, and area under the receiver-operating characteristic (AUROC) curve was used to evaluate the performance of three cancer risk models: the first using only clinical risk factors, the second using only density-related measures and the third using both clinical risk factors and density-related measures. The risk factor-based model generated an AUROC of 0.535, while the model including only breast density-related measures generated a significantly higher AUROC of 0.622 (p risk factor model (p cancer compared with clinical risk factors. Breast cancer risk models based on density-related measures alone can outperform risk models based on clinical factors. Such models may support the development of personalized breast-screening protocols.

  6. Absolute dose measurement Gafchromic R EBT2 movies. Case Study of Kaposis sarcoma; Medida de dosis absoluta con peliculas Gafchromic EBT2. Caso practico de un sarcoma de Kaposi

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, L.; Moral, F. del; Meilan, E.; Azevedo Gomes, J. C. de; Tejeiro Garcia, A. G.; Andrade Alvarez, B.; Vazquez, J.; Nieto, I.; Medal, D.; Lopez Medina, A.; Francisco, S.; Salgado, M.; Munoz, V.

    2011-07-01

    Because of its high spatial resolution, low energy dependence and good response over a wide energy range, EBT2 Gafchromic films are widely used in many applications in radiotherapy for measuring relative dose. Despite being the most common use can be used to measure absolute dose. This text is an example of using films as EBT2 for in vivo absolute dose in a Kaposis sarcoma.

  7. High-resolution tangential absolute extreme ultraviolet arrays for radiated power density measurements on NSTX-U.

    Science.gov (United States)

    Delgado-Aparicio, L; Bell, R E; Faust, I; Tritz, K; Diallo, A; Gerhardt, S P; Kozub, T A; LeBlanc, B P; Stratton, B C

    2014-11-01

    The radiated-power-density diagnostic on the equatorial midplane for the NSTX-U tokamak will be upgraded to measure the radial structure of the photon emissivity profile with an improved radial resolution. This diagnostic will enhance the characterization and studies of power balance, impurity transport, and MHD. The layout and response expected of the new system is shown for different plasma conditions and impurity concentrations. The effect of toroidal rotation driving poloidal asymmetries in the core radiation from high-Z impurities is also addressed.

  8. Absolute Gravimetry in Fennoscandia

    DEFF Research Database (Denmark)

    Pettersen, B. R; TImmen, L.; Gitlein, O.

    away from this central location. An oval shaped zero uplift isoline tracks the general western and northern coastline of Norway and the Kola peninsula. It returns southwest through Russian Karelia and touches the southern tip of Sweden and northern Denmark. The uplift area (as measured by present day...... motions) has its major axis in the direction of southwest to northeast and covers a distance of about 2000 km. Absolute gravimetry was made in Finland and Norway in 1976 with a rise-and fall instrument. A decade later the number of gravity stations was expanded by JILAg-5, in Finland from 1988, in Norway...... acquired by IfE (FG5-220), FGI (FG5-221), and UMB (FG5-226). New absolute gravity stations were established by the national mapping agencies in Denmark, Norway, and Sweden. The total number of prepared sites in Fennoscandia is now about 30. Most of them are co-located with permanent GPS, for many of which...

  9. Determination of absolute Ba densities during dimming operation of fluorescent lamps by laser-induced fluorescence measurements

    Science.gov (United States)

    Hadrath, S.; Beck, M.; Garner, R. C.; Lieder, G.; Ehlbeck, J.

    2007-01-01

    Investigations of fluorescent lamps (FL) are often focused on the electrodes, since the lifetime of the lamps is typically limited by the electrode lifetime and durability. During steady state operation, the work function lowering emitter material, in particular, barium, is lost. Greater barium losses occur under dimming conditions, in which reduced discharge currents lead to increased cathode falls, the result of the otherwise diminished heating of the electrode by the bombarding plasma ions. In this work the barium density near the electrodes of (FL), operating in high frequency dimming mode is investigated using the high-sensitivity method of laser-induced fluorescence. From these measurements we infer barium loss for a range of discharge currents and auxiliary coil heating currents. We show that the Ba loss can very easily be reduced by moderate auxiliary coil heating.

  10. Determination of absolute Ba densities during dimming operation of fluorescent lamps by laser-induced fluorescence measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hadrath, S [Institute of Low-Temperature Plasma Physics, Friedrich-Ludwig-Jahn-Str. 19, D-17489 Greifswald (Germany); Beck, M [FL/CFL D-A, Osram GmbH, Berliner Allee 65, D-86136 Augsburg (Germany); Garner, R C [Central Research and Services Laboratory, OSRAM Sylvania, 71 Cherry Hill Dr, Beverly, MA, 01915 (United States); Lieder, G [Research Light Sources, Osram GmbH, Hellabrunner Str. 1, D-81536 Munich (Germany); Ehlbeck, J [Institute of Low-Temperature Plasma Physics, Friedrich-Ludwig-Jahn-Str. 19, D-17489 Greifswald (Germany)

    2007-01-07

    Investigations of fluorescent lamps (FL) are often focused on the electrodes, since the lifetime of the lamps is typically limited by the electrode lifetime and durability. During steady state operation, the work function lowering emitter material, in particular, barium, is lost. Greater barium losses occur under dimming conditions, in which reduced discharge currents lead to increased cathode falls, the result of the otherwise diminished heating of the electrode by the bombarding plasma ions. In this work the barium density near the electrodes of (FL), operating in high frequency dimming mode is investigated using the high-sensitivity method of laser-induced fluorescence. From these measurements we infer barium loss for a range of discharge currents and auxiliary coil heating currents. We show that the Ba loss can very easily be reduced by moderate auxiliary coil heating.

  11. Measurement of the Absolute Branching Fractions B to Dpi, D*pi, D**pi with a Missing Mass Method

    CERN Document Server

    Aubert, B; Boutigny, D; Couderc, F; Karyotakis, Yu; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Graugès-Pous, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Del, P; Amo Sanchez; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schröder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Asgeirsson, D J; Çuhadar-Dönszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M A; Mommsen, R K; Röthel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Merkel, J; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, C; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo, M; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Panduro-Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Le Diberder, F R; Lepeltier, V; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wang, W F; Wormser, G; Cheng, C H; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flächer, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Wren, A C; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Stängle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; Mclachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; al, et

    2006-01-01

    We present branching fraction measurements of charged and neutral B decays to Dpi-, D*pi- and D**pi- with a missing mass method, based on a sample of 231 million Y(4S)-->BBar pairs collected by the BaBar detector at the PEP-II e+e- collider. One of the B mesons is fully reconstructed and the other one decays to a reconstructed charged pion and a companion charmed meson identified by its recoil mass, inferred by kinematics. Here D** refers to the sum of all the non-strange charm meson states with masses in the range 2.2-2.8 Gev/c2.

  12. 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.

  13. Ion recombination correction factor in scanned light-ion beams for absolute dose measurement using plane-parallel ionisation chambers.

    Science.gov (United States)

    Rossomme, S; Horn, J; Brons, S; Jäkel, O; Mairani, A; Ciocca, M; Floquet, V; Romano, F; Rodriguez Garcia, D; Vynckier, S; Palmans, H

    2017-07-07

    Based on international reference dosimetry protocols for light-ion beams, a correction factor (k s) has to be applied to the response of a plane-parallel ionisation chamber, to account for recombination of negative and positive charges in its air cavity before these charges can be collected on the electrodes. In this work, k s for IBA PPC40 Roos-type chambers is investigated in four scanned light-ion beams (proton, helium, carbon and oxygen). To take into account the high dose-rates used with scanned beams and LET-values, experimental results are compared to a model combining two theories. One theory, developed by Jaffé, describes the variation of k s with the ionization density within the ion track (initial recombination) and the other theory, developed by Boag, describes the variation of k s with the dose rate (volume recombination). Excellent agreement is found between experimental and theoretical k s-values. All results confirm that k s cannot be neglected. The solution to minimise k s is to use the ionisation chamber at high voltage. However, one must be aware that charge multiplication may complicate the interpretation of the measurement. For the chamber tested, it was found that a voltage of 300 V can be used without further complication. As the initial recombination has a logarithmic variation as a function of 1/V, the two-voltage method is not applicable to these scanned beams.

  14. Comparative and Absolute Measurements of 11 Inorganic Constituents of 38 Human Tooth Samples with Gamma-ray Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Samsahl, K. [AB Atomenergi, Stockholm (Sweden); Soeremark, R. [The Clinical Laboratory and the Dept. of Prosthetics of the Royal School of Dentistry, Stockholm (Sweden)

    1961-12-15

    The mean concentrations of the following elements have been simultaneously determined in normal human dentine, enamel and dental calculus with gamma-ray spectrometry; Na, P, Cl, Ca, Mn, Cu, Zn, Br, Sr, W and Au. In a typical run one sample each of dentine, enamel and dental calculus were irradiated together with standards of the elements to be determined in a thermal neutron flux of 2 x 10{sup 12} n/cm/sec for 20 hours. The chemical elements were separated into nine groups with ion exchange technique before the subsequent gamma spectrometric measurements. One man can manage the chemical separations and take the necessary gamma spectra from a run in one day. In a few samples of dentine, enamel and dental calculus which had been irradiated in a thermal neutron flux of 7 x 10{sup 13} n/cm/sec for one week the additional long lived trace elements were qualitatively determined Cr, Fe, Co, Rb, Ag, Sb, Cs and Ba.

  15. Hydroxyl-radical-induced degradative oxidation of beta-lactam antibiotics in water: absolute rate constant measurements.

    Science.gov (United States)

    Dail, Michelle K; Mezyk, Stephen P

    2010-08-19

    The beta-lactam antibiotics are some of the most prevalent pharmaceutical contaminants currently being detected in aquatic environments. Because the presence of any trace level of antibiotic in water may adversely affect aquatic ecosystems and contribute to the production of antibiotic-resistant bacteria, active removal by additional water treatments, such as using advanced oxidation and reduction processes (AO/RPs), may be required. However, to ensure that any AOP treatment process occurs efficiently and quantitatively, a full understanding of the kinetics and mechanisms of all of the chemical reactions involved under the conditions of use is necessary. In this study, we report on our kinetic measurements for the hydroxyl-radical-induced oxidation of 11 beta-lactam antibiotics obtained using electron pulse radiolysis techniques. For the 5-member ring species, an average reaction rate constant of (7.9 +/- 0.8) x 10(9) M(-1) s(-1) was obtained, slightly faster than for the analogous 6-member ring containing antibiotics, (6.6 +/- 1.2) x 10(9) M(-1) s(-1). The consistency of these rate constants for each group infers a common reaction mechanism, consisting of the partitioning of the hydroxyl radical between addition to peripheral aromatic rings and reaction with the central double-ring core of these antibiotics.

  16. Measurements of the absolute photoionization cross section of Fe{sup +} ions from 15.8 to 180 eV

    Energy Technology Data Exchange (ETDEWEB)

    Kjeldsen, H. [Institute of Physics and Astronomy, University of Aarhus, Aarhus (Germany)]. E-mail: kjeldsen@ifa.au.dk; Kristensen, B.; Folkmann, F.; Andersen, T. [Institute of Physics and Astronomy, University of Aarhus, Aarhus (Germany)

    2002-09-14

    The absolute single-and double-photoionization cross sections of singly charged Fe ions have been measured from 15.8 to 180 eV using the merged-beam technique. The data yield information about the photoionization continua and the resonance structures resulting from excitation of the outer 3d and 4s electrons as well as the inner 3p and 3s electrons. The vast majority of the Fe{sup +} target ions were present in the ground-state configuration, 3d{sup 6}4s, and term,{sup 6}D. The experimental data have been compared with several calculations, for example R-matrix calculations from the Opacity Project and data obtained using the central-field approximations. The experimental data are available at http://www.iop.orgww.ifa.au.dk/amo/atomphys/atomphys.htm. (author)

  17. Absolute technique for measuring internal electric fields in InGaN/GaN light-emitting diodes by electroreflectance applicable to all crystal orientations

    Science.gov (United States)

    Tanikawa, Tomoyuki; Shojiki, Kanako; Katayama, Ryuji; Kuboya, Shigeyuki; Matsuoka, Takashi; Honda, Yoshio; Amano, Hiroshi

    2017-08-01

    The internal electric fields in III-polar (0001), N-polar (000\\bar{1}), and semipolar (10\\bar{1}1) InGaN/GaN light-emitting diodes were investigated by electroreflectance (ER) spectroscopy. The ER spectra reflected the difference in the direction and strength of internal electric fields. Phase analyses of the ER signal revealed that only III-polar InGaN wells have the opposite direction of the internal electric field at zero bias voltage; this finding is in good agreement with the results of numerical analyses. Quantitative analyses of internal electric fields were conducted by the linewidth analyses of ER spectra. Our experimental results indicate that the absolute value of internal electric fields can be measured from ER spectra.

  18. Absolute-magnetic-field measurement using nanogranular in-gap magnetic sensor with second-harmonic and liquid-nitrogen-temperature operation

    Science.gov (United States)

    Tsukada, Keiji; Yasugi, Takuya; Majima, Yatsuse; Sakai, Kenji; Kiwa, Toshihiko

    2017-05-01

    To detect the absolute magnetic field, such as the earth's magnetic field, a linear magnetic response, a zero point, and thermal stability are required. We thus propose an operating method and sensor probe consisting of a nanogranular in-gap magnetic sensor (GIGS), an operational amplifier integrated circuit, and a modulation coil. The sensor probe was operated in second-harmonic mode at a liquid-nitrogen (Liq. N2) temperature. When an AC magnetic field was applied to GIGS, the second-harmonic signal was generated and modulated by the outer magnetic field to be measured. After lock-in detection, the modulated output signal showed good linearity and a zero point. Moreover, higher sensitivity and low noise with low thermal fluctuation was obtained by the cooling at Liq. N2 temperature.

  19. Absolute-magnetic-field measurement using nanogranular in-gap magnetic sensor with second-harmonic and liquid-nitrogen-temperature operation

    Directory of Open Access Journals (Sweden)

    Keiji Tsukada

    2017-05-01

    Full Text Available To detect the absolute magnetic field, such as the earth’s magnetic field, a linear magnetic response, a zero point, and thermal stability are required. We thus propose an operating method and sensor probe consisting of a nanogranular in-gap magnetic sensor (GIGS, an operational amplifier integrated circuit, and a modulation coil. The sensor probe was operated in second-harmonic mode at a liquid-nitrogen (Liq. N2 temperature. When an AC magnetic field was applied to GIGS, the second-harmonic signal was generated and modulated by the outer magnetic field to be measured. After lock-in detection, the modulated output signal showed good linearity and a zero point. Moreover, higher sensitivity and low noise with low thermal fluctuation was obtained by the cooling at Liq. N2 temperature.

  20. Absolutely calibrated mass spectrometry measurement of reactive and stable plasma chemistry products in the effluent of a He/H2O atmospheric plasma

    Science.gov (United States)

    Willems, Gert; Benedikt, Jan; von Keudell, Achim

    2017-08-01

    Mass spectrometry has been used to analyse the effluent of a micro-scaled atmospheric plasma jet operated in helium with a controlled concentration of water vapour. Absolute densities of H2O2 and OH have been measured as function of water vapour concentration and distance from the jet nozzle. The trend for both species densities are correlated and after an initial increase, the densities of H2O2 and OH saturate around 5000 ppm to 6000 ppm of water admixture. The largest densities for H2O2 (2.37× 1014 cm-3 ) and OH (1.96× 1014 cm-3 ) were measured at 7980 ppm water admixture and 2 mm distance from the jet. Densities of HO2 (1× 1014 cm-3 ) and O2 (4× 1014 cm-3 ) have been measured as well, although no trend could be observed. The direct electron impact ionisation cross-section of H2O2 at 70 eV electron energy was experimentally determined to be 1.02 × 10-16 cm2 . The measured densities and profiles have been compared to a 2D axially symmetric fluid model of species transport and recombination reactions. The effluent reaction chemistry is dominated by the hydroxyl radical, where the hydrogen atoms seem to play an important role as well. The analysis of neutral plasma chemistry products have been complemented by measurements of qualitative ion signals.

  1. 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.

  2. The Cambridge Face Tracker: Accurate, Low Cost Measurement of Head Posture Using Computer Vision and Face Recognition Software.

    Science.gov (United States)

    Thomas, Peter B M; Baltrušaitis, Tadas; Robinson, Peter; Vivian, Anthony J

    2016-09-01

    We validate a video-based method of head posture measurement. The Cambridge Face Tracker uses neural networks (constrained local neural fields) to recognize facial features in video. The relative position of these facial features is used to calculate head posture. First, we assess the accuracy of this approach against videos in three research databases where each frame is tagged with a precisely measured head posture. Second, we compare our method to a commercially available mechanical device, the Cervical Range of Motion device: four subjects each adopted 43 distinct head postures that were measured using both methods. The Cambridge Face Tracker achieved confident facial recognition in 92% of the approximately 38,000 frames of video from the three databases. The respective mean error in absolute head posture was 3.34°, 3.86°, and 2.81°, with a median error of 1.97°, 2.16°, and 1.96°. The accuracy decreased with more extreme head posture. Comparing The Cambridge Face Tracker to the Cervical Range of Motion Device gave correlation coefficients of 0.99 ( P Cambridge Face Tracker performs well under real-world conditions and within the range of normally-encountered head posture. It allows useful quantification of head posture in real time or from precaptured video. Its performance is similar to that of a clinically validated mechanical device. It has significant advantages over other approaches in that subjects do not need to wear any apparatus, and it requires only low cost, easy-to-setup consumer electronics. Noncontact assessment of head posture allows more complete clinical assessment of patients, and could benefit surgical planning in future.

  3. Absolute noninvasive measurement of CO2 mole fraction emitted by E. coli and S. aureus using calibration-free 2f WMS applied to a 2004  nm VCSEL.

    Science.gov (United States)

    Zarin, A S; Chakraborty, Arup Lal; Upadhyay, Abhishek

    2017-06-01

    We report the first demonstration, to the best of our knowledge, of accurate real-time noninvasive measurement of the absolute cumulative mole fraction of metabolic carbon dioxide emitted by Escherichia coli and Staphylococcus aureus over a period of several hours of their life cycles using a recently developed calibration-free wavelength modulation spectroscopy technique. A 1 mW vertical-cavity surface-emitting laser is used to interrogate a single rotational vibrational absorption line of carbon dioxide at 2003.5 nm. The measurements are immune to laser intensity fluctuations and variable optical coupling that is inevitable in such free-space coupled experiments that run over 10-18 h. The cumulative carbon dioxide mole fraction follows the characteristic modified Gompertz model that is typical of bacterial growth in batch cultures. The characteristic growth parameters are extracted from this curve. The technique can be readily extended to study multiple volatile organic compounds that bacteria are known to emit.

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

    Energy Technology Data Exchange (ETDEWEB)

    Öz, E.; Batsch, F.; Muggli, P.

    2016-09-01

    A method to accurately measure the density of Rb vapor is described. We plan on using this method for the Advanced Wakefield (AWAKE) (Assmann et al., 2014 [1]) project at CERN , which will be the world's first proton driven plasma wakefield experiment. The method is similar to the hook (Marlow, 1967 [2]) method and has been described in great detail in the work by Hill et al. (1986) [3]. 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 prototype 8 cm long novel Rb vapor cell.

  5. 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.

  6. Measuring the absolute disintegration rate of a radioactive gas with a moveable endplate discharge counter (MEP) and theoretical calculation of wall effect

    Energy Technology Data Exchange (ETDEWEB)

    Jaffey, A.H.; Gray, J.; Bentley, W.C.; Lerner, J.L.

    1987-09-01

    A precision built moveable endplate Geiger-Mueller counter was used to measure the absolute disintegration rate of a beta-emitting radioactive gas. A Geiger-Mueller counter used for measuring gaseous radioactivity has <100% counting efficiency owing to two factors: (1) ''end effect,'' due to decreased and distorted fields at the ends where wire-insulator joints are placed, and (2) ''wall effect,'' due to non-ionization by beta particles emitted near to and heading into the wall. The end effect was evaluated by making one end of the counter movable and measuring counting rates at a number of endplate positions. Much of the wall effect was calculated theoretically, based on known data for primary ionization of electrons as a function of energy and gas composition. Corrections were then made for the ''shakeoff'' effect in beta decay and for backscattering of electrons from the counter wall. Measurements and calculations were made for a sample of /sup 85/Kr (beta energy, 0.67 MeV). The wall effect calculation is readily extendable to other beta energies.

  7. Changes in mortality inequalities across occupations in Japan: a national register based study of absolute and relative measures, 1980-2010.

    Science.gov (United States)

    Tanaka, Hirokazu; Toyokawa, Satoshi; Tamiya, Nanako; Takahashi, Hideto; Noguchi, Haruko; Kobayashi, Yasuki

    2017-09-05

    Changes in mortality inequalities across socioeconomic groups have been a substantial public health concern worldwide. We investigated changes in absolute/relative mortality inequalities across occupations, and the contribution of different diseases to inequalities in tandem with the restructuring of the Japanese economy. Using complete Japanese national death registries from 5 year intervals (1980-2010), all cause and cause specific age standardised mortality rates (ASMR per 100 000 people standardised using the Japanese standard population in 1985, aged 30-59 years) across 12 occupations were computed. Absolute and relative inequalities were measured in ASMR differences (RDs) and ASMR ratios (RRs) among occupations in comparison with manufacturing workers (reference). We also estimated the changing contribution of different diseases by calculating the differences in ASMR change between 1995 and 2010 for occupations and reference. All cause ASMRs tended to decrease in both sexes over the three decades except for male managers (increased by 71% points, 1995-2010). RDs across occupations were reduced for both sexes (civil servants 233.5 to -1.9 for men; sales workers 63.3 to 4.5 for women) but RRs increased for some occupations (professional workers 1.38 to 1.70; service workers 2.35 to 3.73) for men and decreased for women from 1980 to 2010. Male relative inequalities widened among farmer, fishery and service workers, because the percentage declines were smaller in these occupations. Cerebrovascular disease and cancer were the main causes of the decrease in mortality inequalities among sexes but the incidence of suicide increased among men, thereby increasing sex related inequalities. Absolute inequality trends in mortality across occupations decreased in both sexes, while relative inequality trends were heterogeneous in Japan. The main drivers of narrowing and widening mortality inequalities were cerebrovascular disease and suicide, respectively. Future

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

    Science.gov (United States)

    Logan, Corina J; Palmstrom, Christin R

    2015-01-01

    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.

  9. 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.

  10. Ultrasonic Measurement of Change in Elasticity due to Endothelium Dependent Relaxation Response by Accurate Detection of Artery-Wall Boundary

    Science.gov (United States)

    Kaneko, Takuya; Hasegawa, Hideyuki; Kanai, Hiroshi

    2007-07-01

    Ross hypothesized that an endothelial dysfunction is considered to be an initial step in atherosclerosis. Endothelial cells, which release nitric oxide (NO) in response to shear stress from blood flow, have a function of relaxing smooth muscle in the media of the arterial wall. For the assessment of the endothelial function, there is a conventional method in which the change in the diameter of the brachial artery caused by flow-mediated dilation (FMD) is measured with ultrasound. However, despite the fact that the collagen-rich hard adventitia does not respond to NO, the conventional method measures the change in diameter depending on the mechanical property of the entire wall including the adventitia. Therefore, we developed a method of measuring the change in the thickness and the elasticity of the brachial artery during a cardiac cycle using the phased tracking method for the evaluation of the mechanical property of only the intima-media region. In this study, the initial positions of echoes from the lumen-intima and media-adventitia boundaries are determined using complex template matching to accurately estimate the minute change in the thickness and the elasticity of the brachial and radial arteries. The ambiguity in the determination of such boundaries was eliminated using complex template matching, and the change in elasticity measured by the proposed method was larger than the change in inner diameter obtained by the conventional method.

  11. The importance of accurate measurement of aortic stiffness in patients with chronic kidney disease and end-stage renal disease.

    Science.gov (United States)

    Adenwalla, Sherna F; Graham-Brown, Matthew P M; Leone, Francesca M T; Burton, James O; McCann, Gerry P

    2017-08-01

    Cardiovascular (CV) disease is the leading cause of death in chronic kidney disease (CKD) and end-stage renal disease (ESRD). A key driver in this pathology is increased aortic stiffness, which is a strong, independent predictor of CV mortality in this population. Aortic stiffening is a potentially modifiable biomarker of CV dysfunction and in risk stratification for patients with CKD and ESRD. Previous work has suggested that therapeutic modification of aortic stiffness may ameliorate CV mortality. Nevertheless, future clinical implementation relies on the ability to accurately and reliably quantify stiffness in renal disease. Pulse wave velocity (PWV) is an indirect measure of stiffness and is the accepted standard for non-invasive assessment of aortic stiffness. It has typically been measured using techniques such as applanation tonometry, which is easy to use but hindered by issues such as the inability to visualize the aorta. Advances in cardiac magnetic resonance imaging now allow direct measurement of stiffness, using aortic distensibility, in addition to PWV. These techniques allow measurement of aortic stiffness locally and are obtainable as part of a comprehensive, multiparametric CV assessment. The evidence cannot yet provide a definitive answer regarding which technique or parameter can be considered superior. This review discusses the advantages and limitations of non-invasive methods that have been used to assess aortic stiffness, the key studies that have assessed aortic stiffness in patients with renal disease and why these tools should be standardized for use in clinical trial work.

  12. ABSOLUTE NEUTRINO MASSES

    DEFF Research Database (Denmark)

    Schechter, J.; Shahid, M. N.

    2012-01-01

    We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos.......We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos....

  13. Accurate measurements of carbon monoxide in humid air using the cavity ring-down spectroscopy (CRDS technique

    Directory of Open Access Journals (Sweden)

    H. Chen

    2013-04-01

    Full Text Available Accurate measurements of carbon monoxide (CO in humid air have been made using the cavity ring-down spectroscopy (CRDS technique. The measurements of CO mole fractions are determined from the strength of its spectral absorption in the near-infrared region (~1.57 μm after removing interferences from adjacent carbon dioxide (CO2 and water vapor (H2O absorption lines. Water correction functions that account for the dilution and pressure-broadening effects as well as absorption line interferences from adjacent CO2 and H2O lines have been derived for CO2 mole fractions between 360–390 ppm and for reported H2O mole fractions between 0–4%. The line interference corrections are independent of CO mole fractions. The dependence of the line interference correction on CO2 abundance is estimated to be approximately −0.3 ppb/100 ppm CO2 for dry mole fractions of CO. Comparisons of water correction functions from different analyzers of the same type show significant differences, making it necessary to perform instrument-specific water tests for each individual analyzer. The CRDS analyzer was flown on an aircraft in Alaska from April to November in 2011, and the accuracy of the CO measurements by the CRDS analyzer has been validated against discrete NOAA/ESRL flask sample measurements made on board the same aircraft, with a mean difference between integrated in situ and flask measurements of −0.6 ppb and a standard deviation of 2.8 ppb. Preliminary testing of CRDS instrumentation that employs improved spectroscopic model functions for CO2, H2O, and CO to fit the raw spectral data (available since the beginning of 2012 indicates a smaller water vapor dependence than the models discussed here, but more work is necessary to fully validate the performance. The CRDS technique provides an accurate and low-maintenance method of monitoring the atmospheric dry mole fractions of CO in humid air streams.

  14. Absolute atomic oxygen density measurements for nanosecond-pulsed atmospheric-pressure plasma jets using two-photon absorption laser-induced fluorescence spectroscopy

    Science.gov (United States)

    Jiang, C.; Carter, C.

    2014-12-01

    Nanosecond-pulsed plasma jets that are generated under ambient air conditions and free from confinement of electrodes have become of great interest in recent years due to their promising applications in medicine and dentistry. Reactive oxygen species that are generated by nanosecond-pulsed, room-temperature non-equilibrium He-O2 plasma jets among others are believed to play an important role during the bactericidal or sterilization processes. We report here absolute measurements of atomic oxygen density in a 1 mm-diameter He/(1%)O2 plasma jet at atmospheric pressure using two-photon absorption laser-induced fluorescence spectroscopy. Oxygen number density on the order of 1013 cm-3 was obtained in a 150 ns, 6 kV single-pulsed plasma jet for an axial distance up to 5 mm above the device nozzle. Temporally resolved O density measurements showed that there are two maxima, separated in time by 60-70 µs, and a total pulse duration of 260-300 µs. Electrostatic modeling indicated that there are high-electric-field regions near the nozzle exit that may be responsible for the observed temporal behavior of the O production. Both the field-distribution-based estimation of the time interval for the O number density profile and a pulse-energy-dependence study confirmed that electric-field-dependent, direct and indirect electron-induced processes play important roles for O production.

  15. Laser diode absorption spectroscopy for accurate CO(2) line parameters at 2 microm: consequences for space-based DIAL measurements and potential biases.

    Science.gov (United States)

    Joly, Lilian; Marnas, Fabien; Gibert, Fabien; Bruneau, Didier; Grouiez, Bruno; Flamant, Pierre H; Durry, Georges; Dumelie, Nicolas; Parvitte, Bertrand; Zéninari, Virginie

    2009-10-10

    Space-based active sensing of CO(2) concentration is a very promising technique for the derivation of CO(2) surface fluxes. There is a need for accurate spectroscopic parameters to enable accurate space-based measurements to address global climatic issues. New spectroscopic measurements using laser diode absorption spectroscopy are presented for the preselected R30 CO(2) absorption line ((20(0)1)(III)space-based DIAL CO(2) mixing ratio measurements associated to spectroscopic parameter uncertainties are presented.

  16. The absolute environmental performance of buildings

    DEFF Research Database (Denmark)

    Brejnrod, Kathrine Nykjær; Kalbar, Pradip; Petersen, Steffen

    2017-01-01

    Our paper presents a novel approach for absolute sustainability assessment of a building's environmental performance. It is demonstrated how the absolute sustainable share of the earth carrying capacity of a specific building type can be estimated using carrying capacity based normalization factors...... sustainability for the standard house were proposed focusing on three measures: minimizing environmental impacts from building construction, minimizing impacts from energy consumption during use phase, and reducing the living area per person. In an intermediate path, absolute sustainability can be obtained...

  17. The gated integration technique for the accurate measurement of the autocorrelation function of speckle intensities scattered from random phase screens

    Science.gov (United States)

    Zhang, Ningyu; Cheng, Chuanfu; Teng, Shuyun; Chen, Xiaoyi; Xu, Zhizhan

    2007-09-01

    A new approach based on the gated integration technique is proposed for the accurate measurement of the autocorrelation function of speckle intensities scattered from a random phase screen. The Boxcar used for this technique in the acquisition of the speckle intensity data integrates the photoelectric signal during its sampling gate open, and it repeats the sampling by a preset number, m. The average analog of the m samplings output by the Boxcar enhances the signal-to-noise ratio by √{m}, because the repeated sampling and the average make the useful speckle signals stable, while the randomly varied photoelectric noise is suppressed by 1/√{m}. In the experiment, we use an analog-to-digital converter module to synchronize all the actions such as the stepped movement of the phase screen, the repeated sampling, the readout of the averaged output of the Boxcar, etc. The experimental results show that speckle signals are better recovered from contaminated signals, and the autocorrelation function with the secondary maximum is obtained, indicating that the accuracy of the measurement of the autocorrelation function is greatly improved by the gated integration technique.

  18. 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; Zhengyu Huang; Yizheng Zhu

    2005-04-01

    This report summarizes technical progress October 2004-March 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 BPDI 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.

  19. Mode-locked semiconductor laser for long and absolute distance measurement based on laser pulse repetition frequency sweeping: a comparative study between three types of lasers

    Science.gov (United States)

    Castro Alves, D.; Abreu, Manuel; Cabral, Alexandre; Rebordão, J. M.

    2017-08-01

    In this work we present a study on three types of semiconductor mode-locked lasers as possible sources for a high precision absolute distance metrology measurement concept based on pulse repetition frequency (PRF) sweep. In this work, we evaluated one vertical emission laser and two transversal emission sources. The topology of the gain element is quantum-well, quantum-dot and quantum-dash, respectively. Only the vertical emission laser has optical pump, whilst the others operate with electric pumping. The quantum-dash laser does not have a saturable absorber in its configuration but relies on a dispersion compensating fiber for generating pulses. The bottleneck of vertical emission laser is his high power density pump (4.5W/165μm), increasing the vulnerability of damaging the gain element. The other lasers, i.e., the single (quantum-dash) and double section (quantum-dot) lasers present good results either in terms of applicability to the metrology system or in terms of robustness. Using RF injection on the gain element, both lasers show good PRF stabilization results (better than σy(10ms) = 10-9 ) which is a requirement for the mentioned metrology technique.

  20. How calibration and reference spectra affect the accuracy of absolute soft X-ray solar irradiance measured by the SDO/EVE/ESP during high solar activity

    Science.gov (United States)

    Didkovsky, Leonid; Wieman, Seth; Woods, Thomas

    2016-10-01

    The Extreme ultraviolet Spectrophotometer (ESP), one of the channels of SDO's Extreme ultraviolet Variability Experiment (EVE), measures solar irradiance in several EUV and soft x-ray (SXR) bands isolated using thin-film filters and a transmission diffraction grating, and includes a quad-diode detector positioned at the grating zeroth-order to observe in a wavelength band from about 0.1 to 7.0 nm. The quad diode signal also includes some contribution from shorter wavelength in the grating's first-order and the ratio of zeroth-order to first-order signal depends on both source geometry, and spectral distribution. For example, radiometric calibration of the ESP zeroth-order at the NIST SURF BL-2 with a near-parallel beam provides a different zeroth-to-first-order ratio than modeled for solar observations. The relative influence of "uncalibrated" first-order irradiance during solar observations is a function of the solar spectral irradiance and the locations of large Active Regions or solar flares. We discuss how the "uncalibrated" first-order "solar" component and the use of variable solar reference spectra affect determination of absolute SXR irradiance which currently may be significantly overestimated during high solar activity.

  1. Measurement of the absolute values of cross-sections in neutron photoproduction (1962); Mesure de sections efficaces de photoproduction de neutrons en valeur absolue (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Schuhl, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-07-01

    The absolute values of photoneutrons production cross-sections for the case of intermediate and heavy nuclei (lanthanium, cerium, tantalum, gold, lead and bismuth) are determined with an error of 15 per cent. The results obtained agree with theories in which the giant resonance is explained by the collective motion of the protons against the neutrons. The effect of the nuclear deformation on the shape of the giant resonance is seen in the case of Ta{sup 181}, it will be possible to determine the quadrupole momenta of deformed nuclei with a good accuracy when we shall increase the statistics of measurements. (author) [French] Les sections efficaces de production de photoneutrons par divers noyaux moyens et lourds (lanthane, cerium, tantale, or, plomb et bismuth) sont determinees en valeur absolue avec une erreur relative de 15 pour cent. Les resultats obtenus s'accordent avec les theories qui interpretent la resonance geante par un mouvement collectif des protons par rapport aux neutrons. L'influence de la deformation du noyau sur la forme de la resonance geante est soulignee dans le cas de {sup 181}Ta pour lequel elle se decompose en deux pics. Une amelioration de la statistique des mesures permettra de determiner les moments quadrupolaires des noyaux deformes avec une meilleure precision. (auteur)

  2. Measurement of absolute density of N atom in sputtering plasma for epitaxial growth ZnO films via nitrogen mediated crystallization

    Science.gov (United States)

    Ide, Tomoaki; Matsushima, Koichi; Takasaki, Toshiyuki; Takeda, Keigo; Hori, Masaru; Yamashita, Daisuke; Seo, Hyuwoong; Koga, Kazunori; Shiratani, Masaharu; Itagaki, Naho

    2015-09-01

    ZnO has attracted attention as a potential alternative to GaN in light emitting diodes because of the wide band gap and large exciton binding energy. Recently, we have developed a fabrication method of ZnO by sputtering, nitrogen mediated crystallization (NMC), enabling us to make epitaxial films with low defect density. By utilizing the buffer layers fabricated by NMC method, we have succeeded in fabrication of single crystalline ZnO films even on 18% lattice mismatched substrates. Here, aiming to clarify effects of nitrogen during NMC process, we measured absolute density of N atom in sputtering plasma by means of vacuum ultra violet absorption spectroscopy. First, NMC-ZnO buffer layers were deposited in Ar/N2 atmosphere. Then, ZnO films were deposited in Ar/O2 atmosphere. With increasing N2 flow rate ratio from 4 to 12%, the N density increases from 3.2 × 1010 to 1.4 × 1011 cm-3. By utilizing the NMC-ZnO buffer layer fabricated at under these conditions, single crystalline ZnO films are grown. However, large number of pits are observed on the surface of ZnO films under N-rich conditions, indicating that N density is of importance in controlling the morphology of ZnO films. This work was supported in part by Japan Society for the Promotion of Science KAKENHI Grant Number 15H05431.

  3. NGS Absolute Gravity Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NGS Absolute Gravity data (78 stations) was received in July 1993. Principal gravity parameters include Gravity Value, Uncertainty, and Vertical Gradient. The...

  4. Determination of the Absolute Luminosity at the LHC

    CERN Document Server

    White, Simon Mathieu; Puzo, P

    2010-01-01

    For particle colliders, the most important performance parameters are the beam energy and the luminosity. High energies allow the particle physics experiments to study and observe new effects. The luminosity describes the ability of the collider to produce the required number of useful interactions or events. It is defined as the proportionality factor between the event rate, measured by the experiments, and the cross section of the observed event which describes its probability to occur. The absolute knowledge of the luminosity therefore allows for the experiments to measure the absolute cross sections. The Large Hadron Collider (LHC) was designed to produce proton proton collisions at a center of mass energy of 14 TeV. This energy would be the highest ever reached in a particle accelerator. The knowledge and understanding of particle physics at such high energy is based on simulations and theoretical predictions. As opposed to e+ e- colliders, for which the Bhabba scattering cross section can be accurately ...

  5. Decoherence at absolute zero

    OpenAIRE

    Sinha, Supurna

    2005-01-01

    We present an analytical study of the loss of quantum coherence at absolute zero. Our model consists of a harmonic oscillator coupled to an environment of harmonic oscillators at absolute zero. We find that for an Ohmic bath, the offdiagonal elements of the density matrix in the position representation decay as a power law in time at late times. This slow loss of coherence in the quantum domain is qualitatively different from the exponential decay observed in studies of high temperature envir...

  6. Accurate delineation of the grounding line from kinematic GPS measurements. Application to an outlet glacier in East Antarctica

    Science.gov (United States)

    Le Meur, E.; Sacchettini, M.; Durand, G.; Drouet, A.; Rignot, E. J.; Mouginot, J.; Young, D. A.; Blankenship, D.; Greenbaum, J.

    2011-12-01

    Polar ice sheets have a huge potential in terms of sea level rise. Recent measurements show clear evidence of a generalized speeding up of outlet glaciers in Greenland and West Antarctica and the question whether similar behaviors are to be expected in East Antarctica is all the more crucial as this latter represents the largest ice reservoir. Moreover, many glaciers in the Wilkes-Terre Adélie sector are in a supposedly unstable configuration due to a landward downsloping bedrock. As a consequence, the Astrolabe Glacier (Terre Adélie land) was selected as a test zone for extensive field surveys like surface and bedrock heights, surface velocities, mass balance measurements. Among those, the exact position of the grounding line is fundamental as it represents a strong transition in the flow regime when the basal drag of the grounded ice reduces to virtually zero when this latter starts to float over the ocean. We here propose a method based on GPS measurements along various profiles in order to identify the presence or not of tidal movements of the ice surface indicating floating ice. The amplitude of the tides of the order of a meter requires accurate data only possible with the differential GPS method. Processing of these GPS data along selected profiles allows us to propose a position for the grounding line (hydrostatic one) which we then compare to that obtained from remote techniques (Landsat-7, ICESat, differential satellite synthetic-aperture radar interferometry). The exact position of the grounding line as well as the exact surface height along a radar transect across the glacier (giving the underlying bedrock topography) is also used to infer a mean density for the whole ice column by applying the hydrostatic criterion and a firn depth correction.

  7. Combining Graphical and Analytical Methods with Molecular Simulations To Analyze Time-Resolved FRET Measurements of Labeled Macromolecules Accurately.

    Science.gov (United States)

    Peulen, Thomas-Otavio; Opanasyuk, Oleg; Seidel, Claus A M

    2017-09-07

    Förster resonance energy transfer (FRET) measurements from a donor, D, to an acceptor, A, fluorophore are frequently used in vitro and in live cells to reveal information on the structure and dynamics of DA labeled macromolecules. Accurate descriptions of FRET measurements by molecular models are complicated because the fluorophores are usually coupled to the macromolecule via flexible long linkers allowing for diffusional exchange between multiple states with different fluorescence properties caused by distinct environmental quenching, dye mobilities, and variable DA distances. It is often assumed for the analysis of fluorescence intensity decays that DA distances and D quenching are uncorrelated (homogeneous quenching by FRET) and that the exchange between distinct fluorophore states is slow (quasistatic). This allows us to introduce the FRET-induced donor decay, εD(t), a function solely depending on the species fraction distribution of the rate constants of energy transfer by FRET, for a convenient joint analysis of fluorescence decays of FRET and reference samples by integrated graphical and analytical procedures. Additionally, we developed a simulation toolkit to model dye diffusion, fluorescence quenching by the protein surface, and FRET. A benchmark study with simulated fluorescence decays of 500 protein structures demonstrates that the quasistatic homogeneous model works very well and recovers for single conformations the average DA distances with an accuracy of FRET-based dynamic structural biology. Finally, we present theories and simulations to assess the accuracy and precision of steady-state and time-resolved FRET measurements in resolving DA distances on the single-molecule and ensemble level and provide a rigorous framework for estimating approximation, systematic, and statistical errors.

  8. 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

  9. Measurement of the absolute branching fraction of D+ → K̅0 e+νe via K̅0 → π 0 π 0

    Science.gov (United States)

    Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Baldini Ferroli, R.; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fedorov, O.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Y.; Huang, Z. L.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kupsc, A.; Kühn, W.; Lange, J. S.; Lara, M.; Larin, P.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Y. B.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lü, H. J.; Lü, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lü, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales Morales, C.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Sarantsev, A.; Savrié, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shi, M.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, W.; Wang, W. P.; Wang, X. F.; Wang, Y.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, L. G.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. N.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.; BESIII Collaboration

    2016-11-01

    By analyzing 2.93 fb-1 data collected at the center-of-mass energy with the BESIII detector, we measure the absolute branching fraction of the semileptonic decay D+ → K̅0 e+νe to be ℬ(D + → K̅0 e+νe) = (8.59 ± 0.14 ± 0.21)% using , where the first uncertainty is statistical and the second systematic. Our result is consistent with previous measurements within uncertainties.. Supported by National Key Basic Research Program of China (2009CB825204, 2015CB856700), National Natural Science Foundation of China (NSFC) (10935007, 11125525, 11235011, 11305180, 11322544, 11335008, 11425524, 11475123), Chinese Academy of Sciences (CAS) Large-Scale Scientific Facility Program, CAS Center for Excellence in Particle Physics (CCEPP), Collaborative Innovation Center for Particles and Interactions (CICPI), Joint Large-Scale Scientific Facility Funds of NSFC and CAS (11179007, U1232201, U1332201, U1532101), CAS (KJCX2-YW-N29, KJCX2-YW-N45), 100 Talents Program of CAS, National 1000 Talents Program of China, INPAC and Shanghai Key Laboratory for Particle Physics and Cosmology, German Research Foundation DFG (Collaborative Research Center CRC-1044), Istituto Nazionale di Fisica Nucleare, Italy, Koninklijke Nederlandse Akademie van Wetenschappen (KNAW) (530-4CDP03), Ministry of Development of Turkey (DPT2006K-120470), National Natural Science Foundation of China (NSFC) (11405046, U1332103), Russian Foundation for Basic Research (14-07-91152), Swedish Resarch Council, U. S. Department of Energy (DE-FG02-04ER41291, DE-FG02-05ER41374, DE-SC0012069, DESC0010118), U.S. National Science Foundation, University of Groningen (RuG) and Helmholtzzentrum fuer Schwerionenforschung GmbH (GSI), Darmstadt, WCU Program of National Research Foundation of Korea (R32-2008-000-10155-0).

  10. Novel concept for the mass spectrometric determination of absolute isotopic abundances with improved measurement uncertainty: Part 1 - theoretical derivation and feasibility study

    Science.gov (United States)

    Rienitz, Olaf; Pramann, Axel; Schiel, Detlef

    2010-01-01

    The development of a new method for the experimental determination of absolute isotopic abundances using a modified isotope dilution mass spectrometry (IDMS) technique is described. The intention and thus main application will be the quantification of molar masses M of highly enriched materials with improved measurement uncertainty (Urel(M) [approximate] 10-8 with k = 2). In part 1 of the current work, the theoretical foundation of the new method and its mathematical derivation is shown in detail, while part 2 will cover the experiments based on the new method described. Its core idea is the introduction of a virtual element (VE) consisting of all isotopes but the one having the largest or smallest abundance. IDMS is used to determine the mass fraction of this VE in its matrix, namely the element itself. A new set of equations serve to calculate all isotopic abundances (even the large one omitted with the introduction of the VE) merely from the mass fraction of the VE. A comprehensive uncertainty budget according to the Guide to the Expression of Uncertainty in Measurement (GUM) was set up in order to discuss and validate the novel concept. The hypothetical input data of the uncertainty budget were estimated to resemble a silicon material highly enriched with respect to 28Si used in the context of the international Avogadro Project. Considering the calculated results, the experimental determination of the molar mass of the above mentioned silicon seems very promising. As far as the authors know, this will be the first time IDMS was applied to determine a molar mass.

  11. SU-F-BRF-13: Investigating the Feasibility of Accurate Dose Measurement in a Deforming Radiochromic Dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Juang, T [Medical Physics Graduate Program, Duke University Medical Center, Durham, NC (United States); Adamovics, J [Rider University, Skillman, NJ (United States); Oldham, M [Duke University Medical Center, Durham, NC (United States)

    2014-06-15

    Purpose: Presage-Def, a deformable radiochromic 3D dosimeter, has been previously shown to have potential for validating deformable image registration algorithms. This work extends this effort to investigate the feasibility of using Presage-Def to validate dose-accumulation algorithms in deforming structures. Methods: Two cylindrical Presage-Def dosimeters (8cm diameter, 4.5cm length) were irradiated in a water-bath with a simple 4-field box treatment. Isocentric dose was 20Gy. One dosimeter served as control (no deformation) while the other was laterally compressed during irradiation by 21%. Both dosimeters were imaged before and after irradiation with a fast (∼10 minutes for 1mm isotropic resolution), broad beam, high resolution optical-CT scanner. Measured dose distributions were compared to corresponding distributions calculated by a commissioned Eclipse planning system. Accuracy in the control was evaluated with 3D gamma (3%/3mm). The dose distribution calculated for the compressed dosimeter in the irradiation geometry cannot be directly compared via profiles or 3D gamma to the measured distribution, which deforms with release from compression. Thus, accuracy under deformation was determined by comparing integral dose within the high dose region of the deformed dosimeter distribution versus calculated dose. Dose profiles were used to study temporal stability of measured dose distributions. Results: Good dose agreement was demonstrated in the control with a 3D gamma passing rate of 96.6%. For the dosimeter irradiated under compression, the measured integral dose in the high dose region (518.0Gy*cm3) was within 6% of the Eclipse-calculated integral dose (549.4Gy*cm3). Elevated signal was noted on the dosimeter edge in the direction of compression. Change in dosimeter signal over 1.5 hours was ≤2.7%, and the relative dose distribution remained stable over this period of time. Conclusion: Presage-Def is promising as a 3D dosimeter capable of accurately

  12. Accurate Laboratory Measurements of Vibration-Rotation Transitions of 36ArH^+ and 38ArH+

    Science.gov (United States)

    Cueto, Maite; Cernicharo, Jose; Herrero, Victor Jose; Tanarro, Isabel; Domenech, Jose Luis

    2014-06-01

    The protonated Ar ion 36ArH^+ has recently been identified in space, in the Crab Nebula, from Herschel spectra. Its R(0) and R(1) transitions lie at 617.5 and 1234.6 GHz, respectively, where atmospheric transmission is rather poor, even for a site as good as that of ALMA. As an alternative, especially after the end of the Herschel mission, rovibrational transitions of ArH^+ could be observed in absorption against bright background sources such as the galactic center, or other objects. We report on accurate laboratory wavenumber measurements of 19 lines of the v=1-0 band of 36ArH^+ and 38ArH^+, using a hollow cathode discharge cell, a difference frequency laser spectrometer and Ar with natural isotopic composition. Of those lines, only eight had been reported before and with much less accuracy. The data have also been used in a Dunham-type global fit of all published laboratory data (IR and sub-mm) of all isotopologues. Barlow et al., Science, 342, 1343 (2013) R.R. Filgueira and C.E. Blom, J. Mol. Spectrosc., 127, 279 (1988) M. Cueto et al, Astrophys. J. Lett, 783, L5 (2014)

  13. Cannulation time is a more accurate measure of cannulation difficulty in endoscopic retrograde cholangiopancreatography than the number of attempts.

    Science.gov (United States)

    Tian, Chenlu; Gamboa, Anthony; Chaudhury, Biswashree; Willingham, Field F; Keilin, Steve; Cai, Qiang

    2013-11-01

    Cannulation of the common bile duct (CBD) is the initial and sometime challenging step in endoscopic retrograde cholangiopancreatography (ERCP) procedure. Endoscopists often use cannulation attempts and cannulation time to grade cannulation difficulty, but a standard system has yet to be established. The objective of this study was to compare cannulation times with numbers of cannulation attempts, as measures of cannulation difficulty. We conducted a prospective study in a tertiary referral center, enrolling 58 patients who were undergoing ERCP for a variety of indications. Cannulation time and the number of cannulation attempts were recorded for each patient. A subset of 14 ERCPs had two observers assessing attempts at cannulation. Cannulation time, number of attempts and inter-observer variability in assessment of attempts were compared and studied. The degree of agreement between two the methods (cannulation times and number of cannulation attempts) was unacceptable. There were considerable discrepancies between attempt tallies from two observers but the mean difference was statistically insignificant. The grade of cannulation difficulty for a given ERCP procedure may differ when different methods are used (total cannulation time vs number of attempts); thus, grading by different methods should not be used interchangeably. Cannulation time is a more objective and more accurate assessment tool for grading cannulation difficulty than the number of attempts to cannulate the papilla.

  14. Urine color, osmolality and specific electrical conductance are not accurate measures of hydration status during postexercise rehydration.

    Science.gov (United States)

    Kovacs, E M; Senden, J M; Brouns, F

    1999-03-01

    The aim of the study was to determine whether urine color, osmolality and specific electrical conductance (SEC) provide an accurate index of hydration status and of fluid requirements during the recovery phase after an acute exercise-induced dehydration. eight well-trained healthy males were dehydrated about 3% of body mass, 3 times, by cycling in the heat. To rehydrate after exercise, three types of drinks frequently consumed by athletes postexercise, i.e. a caffeinated soft drink (CC), a mineral water (MW), or a carbohydrate-electrolyte solution (CES) were ingested ad libitum and in randomized cross-over design during the first 2 hrs of an observation period lasting 6 hrs. urine was sampled each hour for determination of color, osmolality and SEC. Net rehydration was calculated from fluid intake and fluid loss by sweat and urine. Fluid intake amounted 2.6 +/- 0.2 kg for CC, 2.2 +/- 0.2 kg for MW and 2.8 +/- 0.3 kg for CES representing 116%, 96% and 127% of fluid lost by sweat. Urine output showed a negative correlation with color, osmolality and SEC (p 0.05). Urine color, SEC and osmolality are poor indicators of hydration status measured from the balance between fluid intake and urine output up to 6 hrs postexercise.

  15. 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>

  16. 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.

  17. 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

  18. Do measures of surgical effectiveness at 1 year after lumbar spine surgery accurately predict 2-year outcomes?

    Science.gov (United States)

    Adogwa, Owoicho; Elsamadicy, Aladine A; Han, Jing L; Cheng, Joseph; Karikari, Isaac; Bagley, Carlos A

    2016-12-01

    OBJECTIVE With the recent passage of the Patient Protection and Affordable Care Act, there has been a dramatic shift toward critical analyses of quality and longitudinal assessment of subjective and objective outcomes after lumbar spine surgery. Accordingly, the emergence and routine use of real-world institutional registries have been vital to the longitudinal assessment of quality. However, prospectively obtaining longitudinal outcomes for patients at 24 months after spine surgery remains a challenge. The aim of this study was to assess if 12-month measures of treatment effectiveness accurately predict long-term outcomes (24 months). METHODS A nationwide, multiinstitutional, prospective spine outcomes registry was used for this study. Enrollment criteria included available demographic, surgical, and clinical outcomes data. All patients had prospectively collected outcomes measures and a minimum 2-year follow-up. Patient-reported outcomes instruments (Oswestry Disability Index [ODI], SF-36, and visual analog scale [VAS]-back pain/leg pain) were completed before surgery and then at 3, 6, 12, and 24 months after surgery. The Health Transition Index of the SF-36 was used to determine the 1- and 2-year minimum clinically important difference (MCID), and logistic regression modeling was performed to determine if achieving MCID at 1 year adequately predicted improvement and achievement of MCID at 24 months. RESULTS The study group included 969 patients: 300 patients underwent anterior lumbar interbody fusion (ALIF), 606 patients underwent transforaminal lumbar interbody fusion (TLIF), and 63 patients underwent lateral interbody fusion (LLIF). There was a significant correlation between the 12- and 24-month ODI (r = 0.82; p MCID thresholds for ODI at 12 months were 13-fold (p MCID at 24 months. Similarly, for the TLIF and LLIF cohorts, patients achieving MCID thresholds for ODI at 12 months were 13-fold and 14-fold (p MCID at 24 months. Outcome measures obtained at 12

  19. Precise and accurate measurement of U and Th isotopes via ICP-MS using a single solution

    Science.gov (United States)

    Mertz-Kraus, R.; Sharp, W. D.; Ludwig, K. R.

    2012-04-01

    , allowing the sample's 238U/235U ratio to be measured. In step 3, we monitor peak-tails at half-mass positions (229.5, 231.5, 234.5) and on mass 237 while aspirating sample solution. Tail measurement requires a distinct cup configuration to maintain 238U in the cups; however, no sample is consumed during automated cup reconfiguration. We monitor the accuracy of 234U/238U ratios using CRM 145, which gives a weighted mean atom ratio of (5.2846 ± 0.0029) - 10-5 (all errors 2σ), consistent with published and reference values. The reproducibility of 230Th/238U ratios is monitored using the Schwartzwalder Mine secular-equilibrium standard (SM). We detect no bias in 230Th/238U or 234U/238U ratios measured for SM at beam intensities ranging over a factor of four, consistent with accurate correction for IC yields. Aladdin's cave coral (AC-1) was analyzed to check our ICP-MS method (and the preceding purification by ion exchange) on a carbonate and yields a mean age of 125.43 ± 0.38 ka, in agreement with published values. We are currently applying the method to corals, speleothems, pedogenic coatings, and tufas.

  20. Comparison between measurements with the superconducting gravimeter T020 and the absolute gravimeter FG5-221 at Metsähovi, Finland in 2003-2012

    Science.gov (United States)

    Virtanen, H.; Makinen, J.; Bilker-Koivula, M.; Ndrdnen, J.; Ruotsalainen, H.

    2012-12-01

    The superconducting gravimeter (SG) is a relative instrument, which should regularly be compared with an absolute gravimeter (AG) for determination of drift, to connect SG data after longer gaps, and to remove big offsets. Additionally, the scale factor of the SG needs to be determined using simultaneous observations with an AG. Conversely, comparison of SG and AG time series can support AG observations by detecting possible instrument problems in the AG. The SG T020 is recording at Metsähovi gravity laboratory since 1994. Regular AG measurements have taken place between 1988 and 2002 with the JILAg-5 gravimeter and from 2003 onwards with the FG5-221. We have compared results of the SG and the AG between 2003 and 2012. For calibration we have used the time series of both instruments without any corrections. For drift comparison we have corrected the time series of both instruments in a similar way for three effects: tides, polar motion and influence of the atmosphere. When a discrepancy appears between the SG and the AG time series, it may indicate a problem with one of the instruments. For determining which instrument is producing the more plausible result we can compare their data with models of environmental effects in gravity, not included in the above-mentioned three standard corrections. In Metsähovi, the hydrological variation (local-regional-global) is the largest effect. Seasonal variation can be up to 8 μgal peak-to-peak. In addition, loading by the Baltic Sea causes the effects up to 3 μgal. The hydrological signal is seen in both the SG and AG data. More generally, most of the variation in the AG time series is also seen in the SG data and can therefore be attributed to the same environmental effects. Correcting the AG record on the basis of models confirmed by the SG improves considerably the precision of determination of the gravity trend due to postglacial rebound.

  1. Ultraviolet photochemistry of buta-1,3- and buta-1,2-dienes: laser spectroscopic absolute hydrogen atom quantum yield and translational energy distribution measurements.

    Science.gov (United States)

    Hanf, A; Volpp, H-R; Sharma, P; Mittal, J P; Vatsa, R K

    2010-07-14

    Using pulsed H-atom Lyman-alpha laser-induced fluorescence spectroscopy along with a photolytic calibration approach, absolute H-atom product quantum yields of phi(H-b13d) = (0.32+/-0.04) and phi(H-b12d) = (0.36+/-0.04) were measured under collision-free conditions for the 193 nm gas-phase laser flash photolysis of buta-1,3- and buta-1,2-diene at room temperature, which demonstrate that nascent H-atom formation is of comparable importance for both parent molecules. Comparison of the available energy fraction, f(T-b13d) = (0.22+/-0.03) and f(T-b12d) = (0.13+/-0.01), released as H+C(4)H(5) product translational energy with results of impulsive and statistical energy partitioning modeling calculations indicates that for both, buta-1,3- and buta-1,2-diene, H-atom formation is preceded by internal conversion to the respective electronic ground state (S(0)) potential energy surfaces. In addition, values of sigma(b-1,3-d-L alpha) = (3.5+/-0.2)x10(-17) cm(2) and sigma(b-1,2-d-L alpha) = (4.4+/-0.2)x10(-17) cm(2) for the previously unknown Lyman-alpha (121.6 nm) radiation photoabsorption cross sections of buta-1,3- and buta-1,2-diene in the gas-phase were determined.

  2. Inactivation of cerebellar cortical Crus II disrupts temporal processing of absolute timing but not relative timing in voluntary movements

    Directory of Open Access Journals (Sweden)

    Kenji eYamaguchi

    2016-02-01

    Full Text Available Several recent studies have demonstrated that the cerebellum plays an important role in temporal processing at the scale of milliseconds. However, it is not clear whether intrinsic cerebellar function involves the temporal processing of discrete or continuous events. Temporal processing during discrete events functions by counting absolute time like a stopwatch, while during continuous events it measures events at intervals. During the temporal processing of continuous events, animals might respond to rhythmic timing of sequential responses rather than to the absolute durations of intervals. Here, we tested the contribution of the cerebellar cortex to temporal processing of absolute and relative timings in voluntary movements. We injected muscimol and baclofen to a part of the cerebellar cortex of rats. We then tested the accuracy of their absolute or relative timing prediction using two timing tasks requiring almost identical reaching movements. Inactivation of the cerebellar cortex disrupted accurate temporal prediction in the absolute timing task. The rats formed two groups based on the changes to their timing accuracy following one of two distinct patterns which can be described as longer or shorter declines in the accuracy of learned intervals. However, a part of the cerebellar cortical inactivation did not affect the rats’ performance of relative timing tasks. We concluded that a part of the cerebellar cortex, Crus II, contributes to the accurate temporal prediction of absolute timing and that the entire cerebellar cortex may be unnecessary in cases in which accurately knowing the absolute duration of an interval is not required for temporal prediction.

  3. 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

  4. 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

  5. Skin mechanics measured in vivo using torsion: a new and accurate model more sensitive to age, sex and moisturizing treatment.

    Science.gov (United States)

    Salter, D C; McArthur, H C; Crosse, J E; Dickens, A D

    1993-10-01

    Summary Measurements of skin mechanics are required to understand better cracking and flaking of the epidermis and loss of 'elasticity'with age in the dermis. Improvements in torsional testing are described here. The resulting data was fitted to algebraic models, the parameters of which can serve both as a concise description of the responses and as a means of relating them to skin structure and physiology. This investigation looks into the suitability of seven such algebraic models. Five of the models examined here appear to be new. Using the commercially available Dia-Stron DTM Torque Meter with our own software, model parameters were studied as indicators of the effects of age and sex in 41 people, and of skin moisturizing treatments in a further 10 people. The two models in the literature were both found to be substantially less accurate and sensitive representations of experimental data than one of the new models proposed here based on the Weibull distribution. This 'WB model'was consistently the one best able to distinguish differences and detect changes which were statistically significant. The WB model appears to be the most powerful and efficient available. Use of this model makes it possible to demonstrate in vivo a statistically significant mechanical difference between male and pre-menopausal female skin using only one parameter (p= 0.0163, with 18 males and 19 females) and to demonstrate a statistically significant mechanical difference between successive decades of age in female skin using only one parameter (p= 0.0124, n= 24). The two parameters of the model most sensitive to skin structure, function and treatment have been combined to form the axes of a 'Skin condition chart'. Any person can be located on this chart at a point indicating their overall skin condition in mechanical terms and any changes in that condition can be clearly demonstrated by movement across the plot.

  6. Echocardiographic measurements alone do not provide accurate non-invasive selection of annuloplasty band size for robotic mitral valve repair.

    Science.gov (United States)

    Cook, Richard C; Nifong, L Wiley; Lashley, Graham G; Duncan, Robert A; Campbell, Julie A; Law, Y Brandon; Chitwood, W Randolph

    2006-07-01

    Successful mitral valve repair (MVP) is dependent on accurate annuloplasty band sizing. This is difficult and time-consuming when performed via port-access, or through a 4-cm minithoracotomy used in robotically assisted MVP. With the goal of moving toward a less-invasive approach and minimizing cross-clamp time, an attempt was made to determine annuloplasty band size using transesophageal echocardiography (TEE) alone. The intertrigonal distance (ITD) was determined by dividing the left ventricular outflow tract diameter (LVOT: measured on standard midesophageal aortic valve long-axis view) by 0.8. The ITD was compared to a nomogram developed to select the best Cosgrove-Edwards annuloplasty band size. Between July and October, 2004, 11 patients (mean age 52.6 +/- 17.9 years; four Barlow's valves with bileaflet prolapse, four posterior leaflet prolapses, one anterior leaflet prolapse, one rheumatic, one dilated annulus) undergoing robotically assisted MVP had the annuloplasty band chosen using TEE alone. Seven patients (63.6%) had no or mild mitral regurgitation (MR) on postoperative TEE. Three patients (27.2%) had some systolic anterior motion (SAM), with one (Barlow's valve) requiring a second repair (same operation). One patient (9.1%, rheumatic) had grade 2+ MR on postoperative TEE. In this small case series, a substantial proportion of patients had suboptimal immediate postoperative results. This suggests that selection of the annuloplasty band should not be based on a single echocardiographic variable as it depends on the etiology of the MR, and other dimensions of the mitral valve. Further studies are ongoing to develop a non-invasive method for the selection of annuloplasty band size.

  7. A Feasibility Study for Measuring Accurate Chest Compression Depth and Rate on Soft Surfaces Using Two Accelerometers and Spectral Analysis

    Directory of Open Access Journals (Sweden)

    Sofía Ruiz de Gauna

    2016-01-01

    Full Text Available Background. Cardiopulmonary resuscitation (CPR feedback devices are being increasingly used. However, current accelerometer-based devices overestimate chest displacement when CPR is performed on soft surfaces, which may lead to insufficient compression depth. Aim. To assess the performance of a new algorithm for measuring compression depth and rate based on two accelerometers in a simulated resuscitation scenario. Materials and Methods. Compressions were provided to a manikin on two mattresses, foam and sprung, with and without a backboard. One accelerometer was placed on the chest and the second at the manikin’s back. Chest displacement and mattress displacement were calculated from the spectral analysis of the corresponding acceleration every 2 seconds and subtracted to compute the actual sternal-spinal displacement. Compression rate was obtained from the chest acceleration. Results. Median unsigned error in depth was 2.1 mm (4.4%. Error was 2.4 mm in the foam and 1.7 mm in the sprung mattress (p<0.001. Error was 3.1/2.0 mm and 1.8/1.6 mm with/without backboard for foam and sprung, respectively (p<0.001. Median error in rate was 0.9 cpm (1.0%, with no significant differences between test conditions. Conclusion. The system provided accurate feedback on chest compression depth and rate on soft surfaces. Our solution compensated mattress displacement, avoiding overestimation of compression depth when CPR is performed on soft surfaces.

  8. Instrument development for atmospheric radiation measurement (ARM): Status of the Atmospheric Emitted Radiance Interferometer - extended Resolution (AERI-X), the Solar Radiance Transmission Interferometer (SORTI), and the Absolute Solar Transmission Inferometer (ASTI)

    Energy Technology Data Exchange (ETDEWEB)

    Murcray, F.; Stephen, T.; Kosters, J. [Univ. of Denver, CO (United States)

    1996-04-01

    This paper describes three instruments currently under developemnt for the Atmospheric Radiation Measurement (ARM) Program at the University of Denver: the AERI-X (Atmospheric Emitted Radiance Interferometer-Extended Resolution) and the SORTI (Solar R adiance Transmission Interferometer), and ASTI (Absolute Solar transmission Interferometer).

  9. Measurements of the absolute branching fractions for the semileptonic decays D0 -> K-mu+nu_mu and D0 -> pi-mu+nu_mu

    CERN Document Server

    Ablikim, M; Ban, Y; Cai, X; Chen, H F; Chen, H S; Chen, H X; Chen, J C; Jin Chen; Chen, Y B; Chu, Y P; Dai, Y S; Diao, L Y; Deng, Z Y; Dong, Q F; Du, S X; Fang, J; Fang, S S; Fu, C D; Gao, C S; Gao, Y N; Gu, S D; Gu, Y T; Guo, Y N; He, K L; He, M; Heng, Y K; Hou, J; Hu, H M; Hu, J H; Hu, T; Huang, X T; Ji, X B; Jiang, X S; Jiang, X Y; Jiao, J B; Jin, D P; Jin, S; Lai, Y F; Li, G; Li, H B; Li, J; Li, R Y; Li, S M; Li, W D; Li, W G; Li, X L; Li, X N; Li, X Q; Liang, Y F; Liao, H B; Liu, B J; Liu, C X; Liu, F; Fang, Liu; Liu, H H; Liu, H M; Liu, J; Liu, J B; Liu, J P; Jian, Liu; Liu, Q; Liu, R G; Liu, Z A; Lou, Y C; Lu, F; Lu, G R; Lu, J G; Luo, C L; Ma, F C; Ma, H L; Ma, L L; Ma, Q M; Mao, Z P; Mo, X H; Nie, J; Ping, R G; Qi, N D; Qin, H; Qiu, J F; Ren, Z Y; Rong, G; Ruan, X D; Shan, L Y; Shang, L; Shen, C P; Shen, D L; Shen, X Y; Sheng, H Y; Sun, H S; Sun, S S; Sun, Y Z; Sun, Z J; Tang, X; Tong, G L; Wang, D Y; Wang, L; Wang, L L; Wang, L S; Wang, M; Wang, P; Wang, P L; Wang, Y F; Wang, Z; Wang, Z Y; Zheng,Wang; Wei, C L; Wei, D H; Weng, Y; Wu, N; Xia, X M; Xie, X X; Xu, G F; Xu, X P; Xu, Y; Yan, M L; Yang, H X; Yang, Y X; Ye, M H; Ye, Y X; Yi, Z Y; Yu, G W; Yuan, C Z; Yuan, Y; Zang, S L; Zeng, Y; Zhang, B X; Zhang, B Y; Zhang, C C; Zhang, D H; Zhang, H Q; Zhang, H Y; Zhang, J W; Zhang, J Y; Zhang, S H; Zhang, X Y; Yiyun,Zhang; Zhang, Z X; Zhang, Z P; Zhao, D X; Zhao, J W; Zhao, M G; Zhao, P P; Zhao, W R; Zhao, Z G; Zheng, H Q; Zheng, J P; Zheng, Z P; Zhou, L; Zhu, K J; Zhu, Q M; Zhu, Y C; Zhu, Y S; Zhu, Z A; Zhuang, B A; Zhuang, X A; Zou, B S

    2006-01-01

    Based on the data sample of 33 pb$^{-1}$ collected at and around 3.773 GeV with the BESII detector at the BEPC collider, the absolute branching fractions for the semileptonic decays $D^0\\to K^-\\mu^+\

  10. Absolute activity measurement of the electron-capture-based radionuclides Ce-139, I-125, Ir-192 and Zn-65 by liquid scintillation coincidence counting

    CSIR Research Space (South Africa)

    Van Wyngaardt, WM

    2006-10-01

    Full Text Available Wyngaardt, B.R.S. Simpson / Applied Radiation and Isotopes 64 (2006) 1454?1458 1457 References Eldridge, J.S., Crowther, P., 1964. Absolute determination of 125I. Nucleonics 22 (6), 56. Funck, E., Larsen, A.N., 1983. The influence from low energy X...

  11. Absolute Poverty Lines

    DEFF Research Database (Denmark)

    Arndt, Channing; Mahrt, Kristi; Tarp, Finn

    2017-01-01

    ’ approach, employing multiple methods, is the best available mode for addressing these limitations. A first fundamental choice is whether to estimate an absolute poverty line at all. Consumption-based poverty metrics provide only a partial view into the welfare of individuals or households, which may or may...

  12. Approach to Absolute Zero

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 10. Approach to Absolute Zero Below 10 milli-Kelvin. R Srinivasan. Series Article Volume 2 Issue 10 October 1997 pp 8-16. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/002/10/0008-0016 ...

  13. Approach To Absolute Zero

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 12. Approach to Absolute Zero Liquefaction of Gases. R Srinivasan. Series Article Volume 1 Issue 12 December 1996 pp 6-16. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/001/12/0006-0016 ...

  14. Absolute-Gravity Workshop planned

    Science.gov (United States)

    Bilham, Roger; Sasagawa, Glenn

    The new FG5 absolute gravimeter has a design goal accuracy of 1 μGal and represents the most recent of a series of gravimeters inspired by advances in gravimeter design by J. Faller at the Joint Institute for Laboratory Astrophysics (JILA) in Boulder, Colo. A 2-day workshop will be held in Boulder from March 22 to 23 to discuss current and future applications of absolute gravity (g). Details of the workshop appear at the end of this article. The instrument is based on the principle of interferometrically measuring the time and position of a weight falling in a vacuum, using a stabilized laser and an atomic clock [cf. Cook, 1967; Faller, 1963; Hammond, 1970; Zumberge, 1981; Niebauer, 1986].

  15. 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...

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

    Energy Technology Data Exchange (ETDEWEB)

    Keller, Sune H [Rigshospitalet, University of Copenhagen, Copenhagen (Denmark); Jakoby, Bjorn [University of Surrey, Guildford (United Kingdom); Hansen, Adam Espe; Svalling, Susanne; Klausen, Thomas L [Rigshospitalet, University of Copenhagen, Copenhagen (Denmark)

    2015-05-18

    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.

  17. Integrated Clinical Decision Support Systems Promote Absolute Cardiovascular Risk Assessment: An Important Primary Prevention Measure in Aboriginal and Torres Strait Islander Primary Health Care

    Directory of Open Access Journals (Sweden)

    Veronica Matthews

    2017-09-01

    Full Text Available BackgroundAboriginal and Torres Strait Islander Australians experience a greater burden of disease compared to non-Indigenous Australians. Around one-fifth of the health disparity is caused by cardiovascular disease (CVD. Despite the importance of absolute cardiovascular risk assessment (CVRA as a screening and early intervention tool, few studies have reported its use within the Australian Indigenous primary health care (PHC sector. This study utilizes data from a large-scale quality improvement program to examine variation in documented CVRA as a primary prevention strategy for individuals without prior CVD across four Australian jurisdictions. We also examine the proportion with elevated risk and follow-up actions recorded.MethodsWe undertook cross-sectional analysis of 2,052 client records from 97 PHC centers to assess CVRA in Indigenous adults aged ≥20 years with no recorded chronic disease diagnosis (2012–2014. Multilevel regression was used to quantify the variation in CVRA attributable to health center and client level factors. The main outcome measure was the proportion of eligible adults who had CVRA recorded. Secondary outcomes were the proportion of clients with elevated risk that had follow-up actions recorded.ResultsApproximately 23% (n = 478 of eligible clients had documented CVRA. Almost all assessments (99% were conducted in the Northern Territory. Within this jurisdiction, there was wide variation between centers in the proportion of clients with documented CVRA (median 38%; range 0–86%. Regression analysis showed health center factors accounted for 48% of the variation. Centers with integrated clinical decision support systems were more likely to document CVRA (OR 21.1; 95% CI 5.4–82.4; p < 0.001. Eleven percent (n = 53 of clients were found with moderate/high CVD risk, of whom almost one-third were under 35 years (n = 16. Documentation of follow-up varied with respect to the targeted risk factor

  18. Absolute luminosity determination for the ATLAS experiment

    CERN Document Server

    AUTHOR|(CDS)2076571; Pauly, Thilo

    ATLAS is one of the four big experiments at the Large Hadron Collider (LHC). In order to accurately measure cross sections, the precise knowledge of the integrated luminosity is a prerequisite. The relative luminosity is measured with various detectors and algorithms. The purpose of the algorithms is to convert raw rates measured by a detector into a quantity which is proportional to the luminosity. In this work, three algorithms linked to the two main ATLAS luminosity detectors are absolutely calibrated: BCMH_EventOR, BCMV_EventOR, and LUCID_EventOR. The determination of the calibration constants is based on Van der Meer (VdM) scans, which were carried out in July and November 2012. The statistical errors of this method are negligible and the precision is limited by systematic uncertainties. The different uncertainty sources are quantitatively estimated. The overall uncertainty on the calibration constants is estimated to be 5.40% for the July VdM scans and 2.50% for the November VdM scans. The November cali...

  19. Danish Towns during Absolutism

    DEFF Research Database (Denmark)

    crisis for the Danish urban community, mainly caused by the devastating effects of the seventeenth century warfare. Some few towns, however, stood out with positive development, first and foremost Copenhagen which flourished in its function as the centre of the Absolutist regime. The book traces both...... the roots of the urban crisis as well as the regional and temporal variations. Many articles provide an overview of urbanisation in both the Kingdom of Denmark and the Duchy of Schleswig, while other articles focus on the economic, social, and cultural urban functions. The Danish Urban Studies Series......This anthology, No. 4 in the Danish Urban Studies Series, presents in English recent significant research on Denmark's urban development during the Age of Absolutism, 1660-1848, and features 13 articles written by leading Danish urban historians. The years of Absolutism were marked by a general...

  20. Absolute quantitation of endogenous proteins with precision and accuracy using a capillary Western system.

    Science.gov (United States)

    Chen, Jin-Qiu; Heldman, Madeleine R; Herrmann, Michelle A; Kedei, Noemi; Woo, Wonhee; Blumberg, Peter M; Goldsmith, Paul K

    2013-11-01

    Precise and accurate quantification of protein expression levels in a complex biological setting is challenging. Here, we describe a method for absolute quantitation of endogenous proteins in cell lysates using an automated capillary immunoassay system, the size-based Simple Western system (recently developed by ProteinSimple). The method was able to accurately measure the absolute amounts of target proteins at picogram or sub-picogram levels per nanogram of cell lysates. The measurements were independent of the cell matrix or the cell lysis buffer and were not affected by different antibody affinities for their specific epitopes. We then applied this method to quantitate absolute levels of expression of protein kinase C (PKC) isoforms in LNCaP and U937 cells, two cell lines used extensively for probing the downstream biological responses to PKC targeted ligands. Our absolute quantitation confirmed the predominance of PKCδ in both cells, supporting the important functional role of this PKC isoform in these cell lines. The method described here provides an approach to accurately quantitate levels of protein expression and correlate protein level with function. In addition to enhanced accuracy relative to conventional Western analysis, it circumvents the distortions inherent in comparison with signal intensities from different antibodies with different affinities. Published by Elsevier Inc.

  1. A vibration correction method for free-fall absolute gravimeters

    Science.gov (United States)

    Qian, J.; Wang, G.; Wu, K.; Wang, L. J.

    2018-02-01

    An accurate determination of gravitational acceleration, usually approximated as 9.8 m s‑2, has been playing an important role in the areas of metrology, geophysics, and geodetics. Absolute gravimetry has been experiencing rapid developments in recent years. Most absolute gravimeters today employ a free-fall method to measure gravitational acceleration. Noise from ground vibration has become one of the most serious factors limiting measurement precision. Compared to vibration isolators, the vibration correction method is a simple and feasible way to reduce the influence of ground vibrations. A modified vibration correction method is proposed and demonstrated. A two-dimensional golden section search algorithm is used to search for the best parameters of the hypothetical transfer function. Experiments using a T-1 absolute gravimeter are performed. It is verified that for an identical group of drop data, the modified method proposed in this paper can achieve better correction effects with much less computation than previous methods. Compared to vibration isolators, the correction method applies to more hostile environments and even dynamic platforms, and is expected to be used in a wider range of applications.

  2. 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

    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...

  3. Measurement of the absolute branching fraction of D-vertical bar -> (K)over-bar(0)e(vertical bar) nu(e) via (K)over-bar(0) -> pi(0)pi(0)

    NARCIS (Netherlands)

    Ablikim, M.; Achasov, N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Ferroli, R. Baldini; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettonin, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Caleaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fedorov, O.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Y.; Huang, Z. L.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolc, O. B.; Kopf, B.; Kornicer, M.; Kupse, A.; Kuehn, W.; Lange, J. S.; Lara, M.; Larin, P.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Y. B.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales, C. Morales; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Sarantsev, A.; Savrie, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shi, M.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, W.; Wang, W. P.; Wang, X. F.; Wang, Y.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. N.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuangig, J.; Zotti, L.; Zou, B. S.; Zou, J. H.

    2016-01-01

    By analyzing 2.93 fb(-1) data collected at the center-of-mass energy root s = 3.773 GeV with the BESIII detector, we measure the absolute branching fraction of the semileptonic decay D+ -> (K) over bar (0)e(+)nu(e) to be B(D (+) -> (K) over bar (0)e(+)nu(e)) = (8.59 +/- 0.14 +/- 0.21)% using (K)

  4. Measurement of absolute frequency of continuous-wave terahertz radiation in real time using a free-running, dual-wavelength mode-locked, erbium-doped fibre laser.

    Science.gov (United States)

    Hu, Guoqing; Mizuguchi, Tatsuya; Zhao, Xin; Minamikawa, Takeo; Mizuno, Takahiko; Yang, Yuli; Li, Cui; Bai, Ming; Zheng, Zheng; Yasui, Takeshi

    2017-02-10

    A single, free-running, dual-wavelength mode-locked, erbium-doped fibre laser was exploited to measure the absolute frequency of continuous-wave terahertz (CW-THz) radiation in real time using dual THz combs of photo-carriers (dual PC-THz combs). Two independent mode-locked laser beams with different wavelengths and different repetition frequencies were generated from this laser and were used to generate dual PC-THz combs having different frequency spacings in photoconductive antennae. Based on the dual PC-THz combs, the absolute frequency of CW-THz radiation was determined with a relative precision of 1.2 × 10-9 and a relative accuracy of 1.4 × 10-9 at a sampling rate of 100 Hz. Real-time determination of the absolute frequency of CW-THz radiation varying over a few tens of GHz was also demonstrated. Use of a single dual-wavelength mode-locked fibre laser, in place of dual mode-locked lasers, greatly reduced the size, complexity, and cost of the measurement system while maintaining the real-time capability and high measurement precision.

  5. 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.

  6. A New CCI ECV Release (v2.0) to Accurately Measure the Sea Level Change (1993-2015)

    Science.gov (United States)

    Legeais, J.; Cazenave, A. A.; Ablain, M.; Gilles, G.; Johannessen, J. A.; Scharffenberg, M. G.; Timms, G.; Andersen, O. B.; Cipollini, P.; Roca, M.; Rudenko, S.; Fernandes, J.; Balmaseda, M.; Quartly, G.; Fenoglio Marc, L.; Meyssignac, B.; Benveniste, J.; Ambrozio, A.; Restano, M.

    2016-12-01

    Accurate monitoring of the sea level is required to better understand its variability and changes. 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 a long-term homogeneous and accurate sea level record. The needs and feedback of the climate research community have been collected and a first version of the sea level ECV product has been generated with the best algorithms and altimeter standards. This record (1993-2014) has been validated by the climate research community. Within phase II (2014-2016), the 15 partner consortium has prepared the production of a new reprocessed homogeneous and accurate altimeter sea level record which will be distributed in Autumn 2016. New level 2 altimeter standards developed and tested within the project as well as external contributions have been identified, processed and evaluated by comparison with a reference for different altimeter missions (TOPEX/Poseidon, Jason-1 & 2, ERS-1 & 2, Envisat and GFO). The main evolutions are associated with the wet troposphere correction (based on the GPD+ algorithm including inter calibration with respect to external sensors) but also to the orbit solutions (POE-E and GFZ15), the ERA-Interim based atmospheric corrections and the FES2014 ocean tide model. A new pole tide solution is used and anomalies are referenced to the MSS DTU15. The presentation will focus on the main achievements of the ESA CCI Sea Level project and on the description of the new SL_cci ECV release covering 1993-2015. The major steps required to produce the reprocessed 23 year climate time series will be described. The impacts of the selected level 2 altimeter standards on the SL_cci ECV have been assessed on different spatial scales (global, regional, mesoscale) and temporal scales (long-term, inter-annual, periodic). A significant improvement is expected compared to the current v1.1, with the main impacts observed on the

  7. Tomosynthesis can facilitate accurate measurement of joint space width under the condition of the oblique incidence of X-rays in patients with rheumatoid arthritis.

    Science.gov (United States)

    Ono, Yohei; Kashihara, Rina; Yasojima, Nobutoshi; Kasahara, Hideki; Shimizu, Yuka; Tamura, Kenichi; Tsutsumi, Kaori; Sutherland, Kenneth; Koike, Takao; Kamishima, Tamotsu

    2016-06-01

    Accurate evaluation of joint space width (JSW) is important in the assessment of rheumatoid arthritis (RA). In clinical radiography of bilateral hands, the oblique incidence of X-rays is unavoidable, which may cause perceptional or measurement error of JSW. The objective of this study was to examine whether tomosynthesis, a recently developed modality, can facilitate a more accurate evaluation of JSW than radiography under the condition of oblique incidence of X-rays. We investigated quantitative errors derived from the oblique incidence of X-rays by imaging phantoms simulating various finger joint spaces using radiographs and tomosynthesis images. We then compared the qualitative results of the modified total Sharp score of a total of 320 joints from 20 patients with RA between these modalities. A quantitative error was prominent when the location of the phantom was shifted along the JSW direction. Modified total Sharp scores of tomosynthesis images were significantly higher than those of radiography, that is to say JSW was regarded as narrower in tomosynthesis than in radiography when finger joints were located where the oblique incidence of X-rays is expected in the JSW direction. Tomosynthesis can facilitate accurate evaluation of JSW in finger joints of patients with RA, even with oblique incidence of X-rays. Accurate evaluation of JSW is necessary for the management of patients with RA. Through phantom and clinical studies, we demonstrate that tomosynthesis may achieve more accurate evaluation of JSW.

  8. 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

    -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...... orientations versus a polarization calibrated probe. A complete set of measurements for one AUT takes less than two hours. The measurement uncertainty for the gain is comparable to the one obtained with the near-field substitution technique and typically does not exceed 0.1 dB (1 sigma)....

  9. The new Absolute Quantum Gravimeter (AQG): first results and perspectives

    Science.gov (United States)

    Bonvalot, Sylvain; Le Moigne, Nicolas; Merlet, Sebastien; Desruelle, Bruno; Lautier-Gaud, Jean; Menoret, Vincent; Vermeulen, Pierre

    2016-04-01

    Cold atom gravimetry represents one of the most innovative evolution in gravity instrumentation since the last 20 years. The concept of measuring the gravitational acceleration by dropping atoms and the development of the first instrumental devices during this last decade quickly revealed the promising perspectives of this new generation of gravity meters enabling accurate and absolute measurements of the Earth's gravity field for a wide range of applications (geophysics, geodesy, metrology, etc.). The Absolute Quantum Gravimeter (AQG) gravity meter, developed by MUQUANS (Talence, France - http://www.muquans.com/) with the support of RESIF, the French Seismologic and Geodetic Network (http://www.resif.fr/) belongs to this new generation of instruments. It also represents the first commercial device based on the utilization of advanced matter-wave interferometry techniques, which allow to characterize precisely the vertical acceleration experienced by a cloud of cold atoms. Recently, the first operational unit (AQG01) has been achieved as a compact transportable gravimeter with the aim of satisfying absolute gravity measurements in laboratory conditions under the following specifications: measurements the μGal level at a few Hz cycling frequency, sensitivity of 50μGal/√Hz, immunity to ground vibrations, easy and quickness of operation, automated continuous data acquisition for several months, etc. In order to evaluate the current performances of the AQG01, several experiments are carried out in collaboration between RESIF user's teams and the MUQUANS manufacturer on different reference gravity sites and laboratories in France. These measurements performed in indoor conditions including simultaneous observations with classical reference gravity instruments (corner-cube absolute gravity meters, relative superconducting meters) as well with the Cold Atom Gravity meter (CAG) developed by LNE-SYRTE, lead to a first objective characterization of the performances of

  10. Are real-ear measurements (REM) accurate when using the modified pressure with stored equalization (MPSE) method?

    Science.gov (United States)

    Shaw, Paul

    2010-06-01

    Audiologists typically verify hearing instrument fitting using real-ear measurements (REM). Recently the modified pressure with stored equalization method (MPSE) has been recommended for use when verifying open non-occluding hearing instruments. The MPSE method does not use a reference microphone to maintain loudspeaker output during real-ear measurements and is therefore susceptible to changes in the signal level at the client's ear which result from movement of the client's head and torso during the verification process. To determine the size of these errors, the real-ear unaided response (REUR) was measured prior to and following the fitting of a non-functioning hearing aid in the contralateral ear. Twenty young adults participated. Identical head positions for the two measurements should yield zero difference measures across all frequencies measured. Loudspeaker-to-client azimuths of 0 degrees and 45 degrees were investigated. Mean difference measures across the frequencies investigated were less than 1 dB for both azimuths with one standard deviation from these mean differences typically less than 1.5 dB. Results suggest that the MPSE method does not introduce clinically significant errors in real-ear measurements when verifying hearing instrument fitting in the population examined.

  11. 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

    acceptably .;ccurate measurements. -2 i i Additionially: it was insisted that measurement and accuract requirements be remoed foom testing standards...under the - full implications o1 those decisions. The first section of this - sport details the investigations that were conducted in ti-e quest for the

  12. The calorimetric wattmeter. An accurate method for power loss measurements in energy optimized apparatus and systems. Main report

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, P.; Madsen, K.D.

    2000-08-01

    A measurement system has been built, for Calorimetric Measurement of power in the range 1-50 watt, at test temperatures between 20 and 70 deg. C. This Measurement System is intended to provide a service to research and development engineers working with Power Electronics. Applications for the Measurement System are precision measurements of the power loss in circuits and components, e.g. coils, transformers and power electronics systems. Power losses in these types of apparatus are characteristically difficult to measure, because of the waveforms of current and voltage which occur, non-linear material properties, very small values of loss, and high efficiency. The main purpose of performing precision measurements is to enable verification of the loss values, and the basic loss mechanisms. Knowledge and improved models obtained in this way will enable improved simulations, which are important in connection with optimisation of the loss characteristics and energy performance of apparatus and systems. The principle of the wattmeter is to make a calorimetric measurement of the form of heat emitted inside a reference surface. An advanced control system is provided, to regulate the temperature inside the reference surface. The temperature gradient across the walls of the reference surface is also controlled, to ensure that all heat is removed from the space via the heat exchanger of the precision measurement system. The design of the wattmeter is flexible, so that several experimental methods may be employed. To further ensure precision measurements the operation conditions of the measurement heat transfer system are optimised to suit the value of power to be measured. Experiments have verified that the mesurement uncertainty is 59 mW in the power range 1 to 10 W, for a test temperature of 30% C. An offset of 60 mW has been observed in this range, giving a final uncertainty on the measured value of {+-} 30 mW. The uncertainty increases to 180 mW in the range 10 to 50 W

  13. Does body mass index accurately reflect body fat? A comparison of anthropometric measures in the longitudinal assessment of fat mass.

    Science.gov (United States)

    Phan, Thao-Ly T; Maresca, Michelle M; Hossain, Jobayer; Datto, George A

    2012-07-01

    To determine which anthropometric measure best correlates with change in fat mass (FM) over time. The authors performed a retrospective cohort study of 76 obese patients (mean body mass index [BMI] 38 kg/m(2) and mean age 13 years) presenting to an obesity clinic between 2005 and 2010. For each patient, during 2 visits, FM was measured by bioelectrical impedance analysis and the following measures obtained: BMI, waist circumference, hip circumference, and neck circumference. Correlation coefficients and linear regression analyses were calculated to examine the relationship between each measure and FM. Change in BMI correlated better with change in FM than any other measure and had the strongest effect on change in FM (P FM.

  14. 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......Stalagmites are natural archives containing detailed information on continental climate variability of the past. Microthermometric measurements of fluid inclusion homogenisation temperatures allow determination of stalagmite formation temperatures by measuring the radius of stable laser...... the uncertainty in determining the formation temperature is provided. We demonstrate that the nominal homogenisation temperature of a single inclusion can be determined with an accuracy of ±0.25 ◦C, if the volume of the inclusion is larger than 105 µm3 . With this method, we could measure in a proof...

  15. The absolute environmental performance of buildings

    DEFF Research Database (Denmark)

    Brejnrod, Kathrine Nykjær; Kalbar, Pradip; Petersen, Steffen

    2017-01-01

    sustainability for the standard house were proposed focusing on three measures: minimizing environmental impacts from building construction, minimizing impacts from energy consumption during use phase, and reducing the living area per person. In an intermediate path, absolute sustainability can be obtained......Our paper presents a novel approach for absolute sustainability assessment of a building's environmental performance. It is demonstrated how the absolute sustainable share of the earth carrying capacity of a specific building type can be estimated using carrying capacity based normalization factors....... A building is considered absolute sustainable if its annual environmental burden is less than its share of the earth environmental carrying capacity. Two case buildings – a standard house and an upcycled single-family house located in Denmark – were assessed according to this approach and both were found...

  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. Utilizing a reference material for assessing absolute tumor mechanical properties in modality independent elastography

    Science.gov (United States)

    Kim, Dong Kyu; Weis, Jared A.; Yankeelov, Thomas E.; Miga, Michael I.

    2014-03-01

    There is currently no reliable method for early characterization of breast cancer response to neoadjuvant chemotherapy (NAC) [1,2]. Given that disruption of normal structural architecture occurs in cancer-bearing tissue, we hypothesize that further structural changes occur in response to NAC. Consequently, we are investigating the use of modalityindependent elastography (MIE) [3-8] as a method for monitoring mechanical integrity to predict long term outcomes in NAC. Recently, we have utilized a Demons non-rigid image registration method that allows 3D elasticity reconstruction in abnormal tissue geometries, making it particularly amenable to the evaluation of breast cancer mechanical properties. While past work has reflected relative elasticity contrast ratios [3], this study improves upon that work by utilizing a known stiffness reference material within the reconstruction framework such that a stiffness map becomes an absolute measure. To test, a polyvinyl alcohol (PVA) cryogel phantom and a silicone rubber mock mouse tumor phantom were constructed with varying mechanical stiffness. Results showed that an absolute measure of stiffness could be obtained based on a reference value. This reference technique demonstrates the ability to generate accurate measurements of absolute stiffness to characterize response to NAC. These results support that `referenced MIE' has the potential to reliably differentiate absolute tumor stiffness with significant contrast from that of surrounding tissue. The use of referenced MIE to obtain absolute quantification of biomarkers is also translatable across length scales such that the characterization method is mechanics-consistent at the small animal and human application.

  18. 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.

  19. 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

    2016-01-01

    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. PMID:27649197

  20. 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

    2017-04-09

    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; therefo